United States
Environmental Protection
Agency
Industrial Environmental Research EPA-600/2-78-188
Laboratory         August 1978
Cincinnati OH 45268
Research and Development
Proceedings
Ninth National
Symposium
on Food Processing
Wastes
March 29-31, 1978
Denver,  Colorado

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                 RESEARCH REPORTING SERIES

 Research reports of the Office of Research and Development, U.S. Environmental
 Protection Agency have been grouped into nine series. These nine broad cate-
 gories were established to facilitate further development and application of en-
 vironmental technology. Elimination of traditional grouping was consciously
 planned to foster technology transfer and a maximum interface in related fields.
 The nine series are:

       1   Environmental Health  Effects Research
       2   Environmental Protection Technology
       3.  Ecological Research
       4.  Environmental Monitoring
       5   Socioeconomic Environmental  Studies
       6   Scientific and Technical Assessment Reports (STAR)
       7   Interagency Energy-Environment Research and Development
       8   "Special' Reports
      9.  Miscellaneous Reports

 This report has been  assigned to the ENVIRONMENTAL PROTECTION TECH-
 NOLOGY series. This series describes research performed to develop and dem-
 onstrate instrumentation, equipment, and methodology to repair or prevent en-
 vironmental degradation from point and non-point sources of pollution. This work
 provides the new or improved technology required for the control and treatment
 of pollution  sources to meet environmental quality standards.
This document is available to the public through the National Technical Informa-
tion Service  Springfield, Virginia 22161.

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                                            EPA-600/2-78-188
                                            August 1978
    PROCEEDINGS NINTH NATIONAL SYMPOSIUM
          ON FOOD PROCESSING WASTES
             March 29 - 31, 1978
              Denver, Colorado
                     by

        Food and Wood Products Branch
Industrial Environmental Research Laboratory
          Corvallis,  Oregon 97330
               Co-sponsored by

    National Food Processors Association
           American Meat Institute
  Southeastern Poultry and Egg Association
   Western States Meat Packers Association
     Pacific Egg and Poultry Association
 American Society of Agricultural Engineers
INDUSTRIAL ENVIRONMENTAL RESEARCH LABORATORY
     OFFICE OF RESEARCH AND DEVELOPMENT
    U.S.  ENVIRONMENTAL PROTECTION AGENCY
           CINCINNATI, OHIO  45268

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                               DISCLAIMER
This report has been reviewed by the Industrial Environmental Research
Laboratory-Cincinnati, U.S. Environmental Protection Agency, and approved
for publication.  Approval does not signify that the contents necessarily
reflect the views and policies of the U.S. Environmental Protection Agency
nor does mention of trade names or commercial products constitute endorse-
ment or recommendation for use.
                                    11

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                                  FOREWORD
     When energy and material resources are extracted, processed, converted,
and used, the related pollutional impacts on our environment and even on our
health often require that new and increasingly more efficient pollution con-
trol methods by used.  The Industrial Environmental Research Laboratory-Cin-
cinnati (lERL-Ci) assists in developing and demonstrating new and improved
methodologies that will meet these needs both efficiently and economically.

     The Ninth National Symposium on Food Processing Wastes was co-sponsored
with the National Food Prodessors Association, American Meat Institute,
Southeastern Poultry and Egg Association, Western States Meat Packers
Association, Pacific Egg and Poultry Association and the American Society
of Agricultural Engineets.  The primary purpose of these symposia is the
dissemination of the latest research, development, and demonstration infor-
mation of process modifications waste treatment, by-product recovery and
water reuse to industry, consultants and government personnel.  Twenty-
four papers are included in this Proceedings as well as the final registra-
tion list.  For more information contact the Food and Wood Products Branch
of the Industrial Pollution Control Division.
                                       David G. Stephan
                                           Director
                         Industrial Environmental Research Laboratory
                                          Cincinnati
                                      111

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                                ABSTRACT
       The Proceedings contains copies of the 24 papers presented at the
Ninth National Symposium on Food Processing  Wastes.   Subjects  included:
processing modifications product and by-product recovery,  wastewater treat-
ment, water recycle and water reuse for several segments of the food pro-
cessing industry.  These segments included: red meat  and poultry, seafood,
dairy, fruit, and vegetable.

       Attendance at the two and one-half day Symposium was approximately
170 with good representation by industry, universities, consulting firms,
as well as state and Federal agencies.
                                   iv

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                               CONTENTS
Foreword	iii
Abstract	             iv
A SUMMARY OF COLD CLIMATE OPERATING EXPERIENCES WITH	
BIOLOGICAL WASTE TREATMENT SYSTEMS IN THE FOOD PROCESSING
INDUSTRY
   C. W. Fulton, P. A. Mulyk, J. Haskill	    1

THE UTILIZATION OF CHEESE WHEY FOR WINE PRODUCTION
   G. M. Palmer, R. F. Marquardt	   61

TREATMENT OF CAUSTIC PIMIENTO WASTEWATER
   T. M. Furlow, P. Chen	   68

OVERLAND FLOW TREATMENT OF DUCK PROCESSING WASTEWATER
IN A COLD CLIMATE
   L. H. Ketchum, Jr	   77

ECONOMICS OF STARCH AND ANIMAL FEED PRODUCTION FROM CULL POTATOES
   J. R. Rosenau, L. F. Whitney, J. R. Haight	   89

NITROGEN FIXING BIOMASS FOR AEROBIC TREATMENT OF SOFT DRINK
BOTTLING PLANT WASTEWATER
   P. Y. Yang, I. S. Ting	100

TREATING TROUT PROCESSING WASTEWATER--A SUCCESSFUL CASE HISTORY
   J. S. Keith	110

RECIRCULATION OF CONTAINER COOLING WATER AS A MEANS OF WATER
CONSERVATION IN FOOD PROCESSING PLANTS	118
   N. L. Jacob

LOW BOD RECIRCULATION STEAM BLANCHING
   D. R. MacGregor, P. Parchomchuk	136

LAND VS. ACTIVATED SLUDGE TREATMENT OF POTATO PROCESSING
WASTEWATER
   K. L. Sirrine	142

A DESIGN PROCEDURE FOR LAND APPLICATION
   E. J. Kroeker, A. Lamb, J. M. Haskill	149
                                   v

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 USING MICROWAVES TO REDUCE POLLUTION FROM SCALDING CHICKENS
    B. F. Miller, S. A. Kula, J. W. Goble, H. L. Enos	173

 ACTIVATED SLUDGE TREATMENT OF WASTEWATERS FROM THE DAIRY PRODUCTS
 INDUSTRY
   P. H. M. Guo, P. J. Fowlie, B. E. Jank	178

 TREATMENT OF BIRD CHILLER WATER FOR REUSE IN PLUMING BROILER
 GIBLETS
    H. S. Lillard	203

 DESIGN AND OPERATION OF A VEGETABLE OIL PLANT WASTEWATER
 TREATMENT SYSTEM FOR FUTURE STANDARDS
    N. J. Smallwood	213

 DISSOLVED AIR FLOTATION TREATMENT OF GULF SHRIMP CANNERY
 WASTEWATER
    A. J. Szabo, L. F. LaFleur, F. R. Wilson	221

 UPGRADING A BREWERY WASTEWATER PRETREATMENT FACILITY FOR THE
 CITY OF WINSTON-SALEM
    C. C. Malone, R.  M. Stein, T. D. Cornett	231

 PHOSPHORUS REMOVAL AND DISINFECTION OF MEAT PACKING LAGOON
 EFFLUENT
    R. T. Beaupre,  M.  D.  Redick	247

 PHYSIOCHEMICAL TREATMENT OF RENDERING WASTEWATER BY ELECTRO-
 COAGULATION
    E. R. Ramirez,  0.  A.  Clemens	265

 PROTEIN RECOVERY FROM MEAT PACKING EFFLUENT
    D. E. Hallmark, J.  C.  Ward, H.  C.  Isaksen,  W.  Adams	288

 A  METHOD OF PHYSICO-CHEMICAL TREATMENT OF  ORGANIC
 WASTEWATERS
    P.  Stephenson	306

 WASTEWATER TREATMENT  AND  REUSE IN AN INDEPENDENT  RENDERING COMPANY
    W.  R.  Isherwood, J. McVaugh	321

 THE IMPACT OF THE  CLEAN WATER ACT OF 1977 ON THE FOOD
PROCESSING INDUSTRY
   C. Schafer	336

THE APPLICATION OF DEEP SHAFT TECHNOLOGY TO THE TREATMENT
OF FOOD PROCESSING WASTEWATER
   D. S. Sandford, P.  Eng, T. Gallo	341

REGISTRATION LIST	359
                                   VI

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            A SUMMARY OF COLD CLIMATE OPERATING EXPERIENCES
                WITH BIOLOGICAL WASTE TREATMENT SYSTEMS
                                IN THE
                       FOOD PROCESSING INDUSTRY

                                  by

             C. W. Fulton*, P. A. Mulyk*, and J. Haskill**
INTRODUCTION

Food processing operations are a source of highly concentrated organic
wastewater which is amenable to stabilization by biological treatment.
A wide variety of biological processes are available and have been
employed by the Industry in an attempt to provide the necessary treatment.
While many treatment systems have been very successful, others have
encountered severe operating problems and performance has not always met
Industry's and regulatory agencies' expectations.  This, has been particularly
true in northern regions, where cold climates impose an additional
hardship on the operation of biological systems.

As part of a project conducted for the Food and Allied Industries,
Abatement and Compliance Branch of the Water Pollution Control Directorate
of Fisheries and Environment Canada, Stanley Associates Engineering Ltd.
conducted site visits to a number of food processing plants in Canada
and the northern United States.  The objective of these visits was to
obtain operating and performance data on biological waste treatment
systems utilized by the Industry, and to discuss the problems being
encountered in their operation.

Plant visits were restricted to those facilities which were considered
by local or Federal regulatory agencies to exemplify best practicable
technology for the Industry.

This paper presents case histories of twelve such plants, outlining
their design criteria, loading rates, treatment efficiencies, operating
experience, and capital and operating costs.  The case histories presented
cover the sectors of the food processing industry outlined below:
 -'Stanley Associates Engineering Ltd., Calgary, Alberta
**Food and Allied Industries, Water Pollution Control Directorate,
  Fisheries and Environment Canada, Ottawa, Ontario

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      1)   Meat and Poultry Processing:       2 poultry plants
                                              3 red meat plants

      2)   Dairy and Milk Processing:          3 plants

      3)   Fruit and Vegetable Processing:     1 potato plant
                                              1 fruit juice plant

      4)   Beverage Industry:                  1 distillery

      5)   Fish Processing:                   1 plant.

 COST DATA

 Difficulty was encountered in gathering reliable information  on capital
 and operating costs for the majority  of plants visited.   In some  cases,
 the information simply did not exist.   Where data on the  capital  cost of
 treatment facilities was provided,  this has been updated  to a November
 1977 value, using an Engineering News  Record Construction Cost Index of
 2660.

 Where  possible, actual operating costs reported by the plants have been
 presented.   However, in the majority of cases,  such data  did  not  exist.
 As  a result, operating costs  for these plants have been estimated on the
 basis  of  the manpower and electrical requirements of the  facility, as
 reported  by plant personnel.   A standard value of $10/hour for manpower
 costs  and 2.5c/kW-hr for electrical power  has been used in calculating
 operating costs,  and to facilitate  comparisons between plants.  The
 manpower  cost is  based on the average  1977 wage rate in the Canadian
 construction industry, while  the energy cost represents the average
 electric  power cost at municipal sewage treatment plants  in Alberta in
 1977.

 The total annual  costs presented include the annual operating cost plus
 an  11%  annual amortization allowance on capital cost (10% interest rate;
 25  year amortization period).   Unit treatment costs (i.e. cost per m  of
 wastewater  treated  and cost per kilogram of  BOD  removed) are based on
 the  total annual  cost  and  quantity of  wastewater  treated  annually.

 MEAT AND  POULTRY  PLANTS

 Plant A

 Plant A is  a  poultry  processing operation  that  slaughters approximately
 18,000 birds/day  on an  8 hr/day,  5 day/week  basis.

An extended aeration plant with integral clarifier,  as shown  in Figure 1,
was installed  in  1972  to treat  an average wastewater flow of  455 m-Vday
 (100,000  Igpd).   As illustrated  in Figure  2  the waste  treatment facilities
 include screening of the raw wastewater, aeration,  clarification  and
physical/chemical treatment of  the clarifier  effluent.

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 FEED
INLET
AERATION
   BASIN
            MECHANICAL
               SURFACE
               AERATOR
                                                  LUD6E RETURN TO
                                                 AERATION BASIN
CLARIFIER
EFFLUENT
WEIRS
                                                                            OUTLET
  CLARIFIER

  SLUDGE
  BLANKET
                                                                            SLUDGE
                                                                            SCRAPING
                                                                            MECHANISM
                               SECTION A-A
                       FIGURE 1  -  AERATION BASIN
                                  WITH INTEGRAL CLARIFIER

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PLANT A
     PROCESS
     EFFLUENT
                                        LAGOON SUPERNATANT
                                                              WASTE SLUDGE
                      VIBRATING
                      SCREEN
AERATION BASIN
WITH INTEGRAL
CLARIFIER
                                                           SLUDGE
                                                           STORAGE
                                                           LAGOON
                                                              SECONDARY
                                                              EFFLUENT
DISCHARGE
     TO
  CREEK
                                                                                                       CHLORINATION
                                                                      CHEMICAL
                                                                      ADDITION
                              FIGURE  2  - Schematic Flow Sheet of Waste Treatment Plant
                                         (Plant A)

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The operating and design criteria for the extended aeration plant are
summarized in Table 1.

Current wastewater flow rates average approximately 318 m /day (70,000
Igpd) and the process is generally achieving BOD- and suspended solids
removals of greater than 95% and 90% respectively.  Clarifier effluent
BOD  concentrations are less than 30 mg/L and suspended solids concentrations
are less than 40 mg/L.

The wasting of biological sludge is practiced very infrequently.   When
carried out, sludge is discharged to an abandoned 3 stage lagoon system
on the plant property.  Supernatant from the lagoon is returned to the
aeration basin during periods of low flow.

Shortly after start-up, a problem of turbulence in the integral secondary
clarifier was encountered.  This was apparently solved by adding anti-
rotational baffles to three sides of the aeration basin.

Freezing problems were also encountered with the integral clarifier,
although these were alleviated by enclosing the clarifier in a metal
structure, and blowing warm air over the liquid surface.

The waste treatment facility is operated and maintained on a part-shift
basis by one man, who is also responsible for maintenance of the plant's
boiler room.

Construction of the plant was completed in April 1972 at a cost of
approximately $257,000 (including tertiary physical/chemical treatment).
Using the ENR construction cost index for updating purposes, this corresponds
to a November 1977 cost of approximately $400,000 as shown in Table 2.

Annual operating and maintenance costs for the extended aeration phase
of the treatment process are estimated at approximately $18,600.

Plant B

Plant B is a poultry operation that slaughters and processes approximately
38,000 birds/8 hour-day, 5 days per week.  All blood, feathers, offal,
and dead-on-arrival and contaminated birds are recovered and sent to an
on-site rendering facility.

Grease is recovered from the process wastewater for rendering by means
of air flotation prior to discharge to a wet-well.  The wastewater from
the wet-well is then pumped to 4 vibrating screens.  The screened waste
flows through a splitter box to an extended aeration plant, which is in
turn followed by a facultative lagoon, as shown in Figure 3.

The extended aeration plant consists of two earthen aeration basins
operated in parallel.  These cells are interconnected to permit series
operation, if so desired.  Overflow from the aeration cells enters a
secondary clarifier and sludge removed from the clarifier bottom is
recycled to the splitter box.

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     TABLE  1  -  OPERATING AND  DESIGN CRITERIA  FOR
               EXTENDED AERATION PROCESS  (PLANT A)
Wastewater Characteristics:
     Flow:     Average:     318 m  /day  (70,000  Igpd) - 5 days/week
                                3
               Design:      455 m  /day  (100,000  Igpd) - 5 days/week
     BOD  :
Range:
Average:
400 - 900 mg/L
600 mg/L
     SS:
Range:
Average:
250 - 500 mg/L
400 mg/L
Organic Loading Rate:
            0.05 kg BOD5/kg MLSS/day
Volumetric Loading Rate
            240 g BOD /day/m
            (15 Ib BOD 71,000 ft3/day)
MLSS Concentration:
            4,000 - 5,000 mg/L
Detention Time:
            3 days
Aeration Requirements:
            19 kW - Mechanical Surface Aerator
                         3
            (14 kW/1000 m  of basin volume)
Secondary Clarifier
  Overflow Rate:
            19.5 m3/day/m2
            (400 Igpd/ft2)

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          TABLE 2 - CAPITAL AND OPERATING COSTS FOR THE
                    EXTENDED AERATION PROCESS (PLANT A)
Capital Cost (adjusted to 1977)  	  $400,000
     Annual Amortized Capital Cost @ 11% 	  $44,000

Operating Costs:

     Manpower:  1040 hr/yr @ $10/hr  	 $10,400

     Electrical Power:
          327,000 kW-hr/yr x $0.025/kW-hr	$ 8,200

Annual Operating Cost                                         $18,600

Total Annual Cost                                             $62,600
          3
Cost per m  Treated                                           $0.75
                                                          ($3.40/1000 I.G.)
Cost per kg BOD  Removed                                      $1.32
                                                             ($0.60/lb)

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                                                                                                                CHLORINATION
                                                                                                                    BASIN
                  PLANT
                    B
oo
                              AIR  FLOTATION
                                TANK
                                                       VIBRATING
                                                         SCREENS
                                                                                                                              DISCHARGE
                                                                                                                                 TO
                                                                                                                              CREEK
POLISHING

  POND
                                            FIGURE 3 - Schematic Flow Sheet of Haste Treatment  Process
                                                       (Plant B)

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Clarifier effluent flows to a 1.6 hectare (4 acre) polishing pond and
effluent from  the pond is chlorinated prior to discharge to a small
receiving stream.

The operating  and design criteria for the extended aeration plant and
lagoon are summarized in Table 3.
                                                          3
Current wastewater flow rates average approximately 1900 m /day (425,000
Igpd).  Effluent from the secondary clarifier contains less than 30 mg/L
BODij and 75 mg/L suspended solids, although this is further reduced to
approximately  10 mg/L BODj. and 15 mg/L suspended solids in the polishing
pond.  Overall BOD^ and suspended solids removals are 98% and 97%,
respectively.

Some problems  have been encountered with the loss of biological solids
from the secondary clarifier.  This has been attributed to sludge
bulking, and to flow surges which result in increased overflow rates in
the clarifier.  Chlorination of return sludge to control filamentous
organism growth and reduce bulking has been conducted on'an experimental
basis but results were inconclusive.  It is believed that flow equalization
would help alleviate the problem, but equipment and facilities are not
available to test this.

The presence of high concentrations of algae in the polishing lagoon in
summer months  imparts a green colour to the final effluent.  For this
reason, the polishing pond has been by-passed for short periods during
the summer to  prevent the discharge of aesthetically unacceptable
effluent.

Winter operation has resulted in some icing problems, particularly with
the rotating skimmer arm of the secondary clarifier.  This has necessitated
removal of the arm in fall to facilitate winter operation.  In addition,
it has been found necessary to chip ice from the umbrella which forms
around the two surface aerators.

Sludge wasting has not been necessary for the past two years, however
when carried out, the sludge is trucked to a landfill site.

The waste treatment plant is operated by one man on a full-time basis.

Capital and operating costs for the treatment plant are presented in
Table 4.  The plant was constructed in 1972 at a cost of approximately
$500,000 (excluding land), which corresponds to a November 1977 cost of
approximately  $780,000, based on the ENR construction cost index.
Annual operating and maintenance costs are estimated at $50,800.

Plant C

Plant C is a hog processing and rendering operation, slaughtering approximately
4,000 hogs/day on an eight hour/day, five day/week basis.

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     TABLE 3 - OPERATING AND DESIGN CRITERIA FOR EXTENDED
               AERATION/POLISHING LAGOON PROCESS (PLANT B)
 Wastewater Characteristics:
      Flow -    Average:   1900 m /day (425,000  Igpd)  -  5  days/week
                (Average  Flow during 8 hour  processing  period  is
                 approximately 38 L/sec)
                (Overnight and Weekend Flow  is  approximately 11 L/sec)
      BOD  :
Range:    300 - 2,000 mg/L
Average:  800 mg/L
      SS:
Range:    300 - 1,000 mg/L
Average:  500 mg/L
Extended Aeration  System:
     Organic Loading Rate:     0.02  -  0.05 kg BOD  /kg MLSS/day
     Volumetric Loading Rate:  160 - 320 g BOD  /day/m
                               (10 - 20 Ib BOD5/1,000  ft3/day)
     MLSS Concentration:
               3800 - 5200 mg/L
     Detention Time:
               5.5 days
     Aeration Requirements:
               2 Mechanical Surface Aerators - 1 @ 56 kW
               and 1 @ 75 kW
               (12 kW/1000 m  of basin volume)
     Secondary Clarifier:
Polishing Lagoon:
     Organic Loading Rate:

     Depth:
               Overflow Rate -
19.5 m3/day/m2
(400 Igpd/ft2)
at 26 L/s (350 Igpm)
               2.2 g/day/m
               (20 Ib BOD /acre/day)
               1.8 m
               (6 ft)
                                   10

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               TABLE 4 - CAPITAL AND OPEPATING COSTS OF
                         EXTENDED AERATION/POLISHING
                         LAGOON PROCESS (PLANT B)
Capital Cost (adjusted to 1977) 	 $780,000
     Annual Amortized Capital Cost @ 11% . t	$85,000

Operating Costs:

     Manpower:  2080 hr/yr @ $10/hr . . , , . T	$20,800

     Electrical Power:  118,000 kW-hr/yr x $0.025/kW-hr . .  $30,000

Annual Operating Cost                                            $50,800

Total Annual Cost                                               $135,000
Cost per m  Treated                                              $0.26
                                                               ($1.20/1000 I.G.)
Cost per kg BOD  Removed                                         $0.33
                                                                ($0.15/lb)

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 The wastewater treatment facility is  comprised  of  an  extended  aeration
 process preceded by anaerobic lagoons.   The  raw waste is  screened, and
 passed through an air  flotation unit  for removal of solids,  fats, and
 grease.  It  then flows to a splitter  box, where it can be diverted to
 either or both of two  anaerobic lagoons  operated in parallel (only one
 anaerobic lagoon is in use at present).   Effluent  from the lagoons
 enters a common aeration basin from which it is discharged to  a secondary
 clarifier.   Clarifier  overflow is then chlorinated and either  discharged
 directly to  a nearby river, or stored in a holding pond if the effluent
 quality is unacceptable.   Sludge from the secondary clarifier  is returned
 to  the aeration tank to maintain an MLSS concentration of approximately
 5,000  mg/L.   Excess sludge is wasted  to  the  anaerobic lagoons  for digestion,
 thereby eliminating any sludge handling  problems.

 A schematic  flow diagram of the treatment process  is  illustrated in
 Figure 4.  Operating and design criteria for the treatment plant are
 summarized in Table 5.

 Winter wastewater temperatures have necessitated construction  of a
 prefabricated building over the final clarifier to reduce icing problems.
 Mechanical failure of  the aerator vanes,  due to ice build-up,  has also
 been encountered.

 The use of the holding pond for effluent  polishing in cold weather has
 been found beneficial  in maintaining  a high  quality effluent on a year-
 round  basis.

 The plant is  maintained  by a  trained  operator on a full-time (8 hr/day,
 5 day/week) basis.   The  operator  monitors influent and  effluent quality,
 sludge settleability,  MLSS  concentration  and dissolved  oxygen  on a daily
 or weekly basis,  depending  upon the stability of the  process performance.
 Close  monitoring  of  the  process has revealed that  significant  power
 savings  can be realized,  without  impairing treatment  performance, by
 operating two  aerators  continuously and  two  only 50%  of the  time.

 Since  its construction  in 1975,  the plant has been producing a final
 effluent with  less  than  30  mg/L BOD   and  suspended solids.   The anaerobic
 lagoon has achieved  approximately 60% removal of BOD  and  50%  of suspended
 solids.  Overall  treatment  efficiency is  approximately  98% for BOD,.
 removal and 96% for  suspended  solids.

No data is available on  the construction  cost of the  plant, but operating
costs are estimated  at approximately  $49,000 annually as  shown in Table 6.

Plant D

Plant D is a small slaughtering and meat  packing facility.  Beef, pork
and lamb are processed at an average rate of approximately 9,000 kg
 (20,000 Ibs)  LWK/day on an  8 hour/day, 5  day/week  basis.
                                    12

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                           PLANT C
                                 SCREEN
                                    AIR
                                    FLOTATION
                                    TANK
                                             WASTE SLUDGE
                                             	1
ANAEROBIC
LAGOON
NO. 1
ANAEROBIC
LAGOON
NO. 2
                                                         I
                                                SLUDGE & ,SCUM PIT
         O
HOLDING POND
DISCHARGE TO
RIVER
     FIGURE 4 - Schematic  Flow Sheet  of  Waste  Treatment Process
                (Plant C)
                             13

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     TABLE 5 - OPERATING AND DESIGN CRITERIA FOR ANAEROBIC
               LAGOON/EXTENDED AERATION PROCESS (PLANT C)
Wastewater Characteristics:
     Flow -    Average:    1820 m3/day (400,000 Igpd)
               Peak:       3410 m3/day (750,000 Igpd)
               Design:     5,000 m3/day (1,100,000 Igpd)
     BOD5:     Range:      700 - 2,000 mg/L
               Average:    1500 mg/L

     SS:       Range:      400 - 1,200 mg/L
               Average:    800 mg/L

Anaerobic Lagoon (under present average flow conditions - i.e. only one
  lagoon in operation)

                                              3
     Organic Loading Rate:    270 g BOD /day/m
                              (17 Ib BOD5/1,000 ft3/day)
     Depth:                   4.6 m (15 ft)
     Detention Time:          7.3 days

Extended Aeration (under present average flow conditions):
     Organic Loading Rate:    <0.04 kg BOD /kg MLSS/day
                                               3
     Volumetric Loading Rate: <176 g BOD /day/m
                               (11 Ib BOD /I,000 ft3/day)
     MLSS Concentration:      5,000 mg/L
     Detention Time:          2.8 days
     Aeration Requirements:   4 Mechanical Surface Aerators @ 37 kW each
                              (20 kW/1000 m3 of Basin Volume)
     Secondary Clarifier
       Overflow Rate:         (2QQ

Polishing Pond (under present average flow conditions):
     Detention Time:          86 days
                                   14

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      TABLE 6 - OPERATING COST OF ANAEROBIC
                LAGOON/EXTENDED AERATION PROCESS (PLANT C)
Capital Cost	Not Available
Operating Costs:
     Manpower:  2080 hr/yr @ $10/hr 	 $20,800


     Electrical Power:  1.1 x 10  kW-hr/yr x
                             $0.025/kW-hr 	 $28.000
Annual Operating Cost                                   $48,800
                               15

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 As shown in Figure 5,  plant wastewater is collected  in a  small  sump and
 pumped to a vibrating  screen for separation of  gross solids.  From here
 it flows to an oxidation ditch,  and finally to  a  secondary  clarifier
 prior to discharge to  a small creek.   Sludge from the clarifier bottom
 may be either returned to the ditch or drawn off  for discharge  to
 drying beds.

 Operating and design criteria for the  oxidation ditch installation are
 presented in Table 7.

 The wastewater flow through the  treatment plant is generally between 14
 and 29 m /day (3,000 and 6,500 Igpd),  5 days per  week.  With few exceptions,
 the process has consistently been able to achieve effluent  BOD,, and
 suspended solids concentrations  of less than 40 and  50  mg/L respectively,
 despite the concentrated and variable  nature of the  waste.  This corresponds
 to  removals of 98% and 90%  for BOD  and suspended solids, respectively.

 The oxidation ditch was  constructed in 1963.  No  data are available on
 the capital cost of the  plant, however,  annual  operating costs are
 estimated at  less  than $3,000, as  calculated in Table 8.

 The operational requirements of  the process  have  been found to be minimal.
 Return sludge from the secondary clarifier  is wasted, as required, by
 discharging it directly  to  sludge  drying beds located on the plant
 property.   Sludge  settleability,  pH, and dissolved oxygen are measured
 on  a  regular  basis.

 Due to  low alkalinity  of  the wastewater,  sodium bicarbonate must be
 added  to  provide buffering  capacity and  to  stabilize  pH in  the 6.5 to
 7.0 range.  Prior  to the  addition  of sodium  bicarbonate, the process was
 operating  relatively unsuccessfully at  a pH  of  approximately 4.7.

 Plant  E

 Plant  E is  a  hog processing  and  rendering operation,  slightly larger
 than Plant  C,  slaughtering  approximately 5,000  hogs per 8 hour day, 5 to
 6 days/week.

The wastewater  treatment  facility  is a  trickling  filter process preceded
by  anaerobic  lagoons.  Pretreatment of wastes from the  kill floor consists
of  screening  followed  by  air  flotation.   Effluent from  the  flotation
unit is combined with  other  processing and domestic wastewater, and sent
to  two anaerobic lagoons  operated  in parallel for biological treatment
and flow equalization.   Lagoon effluent  is then preaerated and pumped to
two plastic media  trickling  filter  towers operated in series.  Secondary
clarification  in two parallel clarifiers and disinfection of effluent is
then carried out prior to discharge to a nearby river.  Sludge from the
clarifiers is returned to the anaerobic  lagoons for digestion.   A schematic
flow diagram of  the process  is illustrated in Figure  6.
                                    16

-------
OXIDATION DITCH
              WASTE SLUDGE
              TO         -"
              DRYING QEDS
                                 RETURN
                                 SLUDGE
OXIDATION
DITCH
EFFLUENT
                                                       SECONDARY
                                                      CLARIFIER
                                                                    DISCHARGE TO
                                                                    CREEK
            FIGURE 5 - Schematic Flow Sheet of Waste Treatment Process
                       (Plant D)

-------
            TABLE 7 - DESIGN AND OPERATING CRITERIA FOR

                      OXIDATION DITCH PROCESS  (PLANT D)
Wastewater Characteristics:


                          3
     Flow:  Average - 26 m /day  (5700 Igpd) - 5 days/week

            (Majority of Daily Flow Occurs in 8-10 hr period)
               Range:    500 - 7,000 mg/L

               Average:  2,200 mg/L
     SS:
Range:    400 - 1,400 mg/L

Average:  600 mg/L
Oxidation Ditch:
     Organic Loading Rate:
     MLSS Concentration:
                    0.12 kg BOD /kg MLSS/day
     Volumetric Loading Rate:      368 g BOD /day/m"
                                   (23 Ib BOD5/1,000 ft /day)
                    3,000 mg/L
     Detent ion Tirae:
                    5.8 days
     Aeration Requirements:
                    3.7 kW Cage Rotor
                                 3
                    (25 kW/1000 m  of basin volume)
                              18

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      TABLE 8 - OPERATING COSTS FOR OXIDATION
                DITCH PROCESS  (PLANT D)
Capital Cost	Not Available



Operating Cost:


     Manpower:  260 hr/yr @ $10/hr  	  $2,600


     Electrical Power:  7,500 kW-hr/yr x
                             $0.025/kW-hr  ....  $  190



Annual Operating Cost                               $2,790
                             19

-------
                                 PUNT E
r
         ANAEROBIC
            LAGOON
                                         AIR
                                         FLOTATION
                                         TANK
    ANAEROBIC
    LAGOON
                                       FRE-AERATION TANK
                                         TRICKLING FILTER
                                         TRICKLING FILTER
                                       SPLITTER SOX
            CLARIFIER^-X
CLARIFIER
                                        CHLORINE
                                        CONTACT
                                        TANK
                                EFFLUENT
                FIGURE 6 - SCHEMATIC FLOW SHEET OF WASTE
                           TREATMENT PROCESS (PLANT E)
                                 20

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Operating and design criteria for the treatment plant are summarized in
Table 9.

Some problems have been encountered with reduced treatment efficiency
and filter freezing during cold weather operation.  The filters, originally
open to the air, have been enclosed to help retain heat and alleviate
this problem.  Some clogging of the distributor arms and filter media
has also been experienced; otherwise the trickling filters have operated
with very few problems.

A distinct odour of hydrogen sulphide was evident in the vicinity of the
anaerobic lagoons, but this has reportedly not caused any complaints
from a nearby residential area.  Sludge removal from the anaerobic cells
has only been required once to date.

The plant is maintained by a trained operator on a full-time basis and
consistently produces a final effluent with less than 70 mg/L BOD^ and
80 mg/L of suspended solids (greater than 97%"removal of both parameters).
The anaerobic lagoons are providing approximately 60% BOD,, removal and
65% removal of suspended solids.

The treatment plant construction was completed in 1969 at a cost of
$500,000.  As shown in Table 10, the estimated total capital cost of
such a project in 1977 dollars is approximately $1,100,000.  The annual
operating and maintenance cost of the facility is estimated at approximately
$40,000.

DAIRIES AND MILK PRODUCTS PLANTS

Plant F

Plant F is a dairy operation with a peak milk production of approximately
195,000 kg (430,000 Ibs) of raw milk per day.  The principal products
are butter, dried milk, and skim milk powder.  Plant production is
highly seasonal.  During the peak production season (summer), the plant
operates 24 hours per day, 7 days/week.  This drops off to a 16 hour/day,
5 day/week production schedule as the availability of raw milk decreases.
The plant has been forced to shut down during the winter season in
recent years due to insufficient supplies of raw milk to warrant operation.

An oxidation ditch process, as shown in Figure 7, is used to treat an
average wastewater flow of 160 m^/day (35,000 Igpd).  Wastewater is
collected in a wet-well and pumped to a 25 m^ (5,500 gallon) equalization
tank.  The waste flows from the bottom of the tank, at a rate proportional
to static head of liquid in the tank, into an open channel to the oxidation
ditch.   Overflow from the ditch enters a secondary clarifier housed in a
small building which also contains the sludge return pumps.  Clarified
effluent is discharged to a nearby river.

Design and operating criteria are summarized in Table 11.
                                    21

-------
          TABLE  9 -  OPERATING AND DESIGN CRITERIA FOR ANAEROBIC
                    LAGOON/TRICKLING FILTER PROCESS  (PLANT E)

Wastewater  Characteristics:

     Flow:      Range:    1820 - 3180 m3/day  (400,000 - 700,000 Igpd)
                Average:  2730 m /day  (600,000 Igpd)
     BOD  :     Range:    2,000 - 5,000 mg/L
               Average:  3,000 mg/L
     SS:
Range:    2,000 - 4,000 mg/L
Average:  3,000 mg/L
Anaerobic Lagoons:
     Organic Loading:    320 g BOD^/day/nT
                         (20 Ib BOD 71,000 ft /day)
     Depth:
          4.3 m (14 ft)
     Detention Time:     9.7 days
Trickling Filters:
     Organic Loading
                                        Filter No. 1   Filter No. 2
kg BOD /day /m)
(Ib BOD5/1,000 ft3/day)
Hydraulic Loading
3 2
(m /day/m )
(Igpd/ft2)
Depth (m)
Media
864
54
24
500
6.7
PVC
384
24
24
500
6.7
PVC
Secondary Clarifiers:
                             32             2
     Overflow Rate:      28 m /day/m  (565 Igpd/ft )
                                22

-------
          TABLE 10 - PROCESS PERFORMANCE AND COST OF ANAEROBIC
                     LAGOON/EXTENDED AERATION PROCESS (Plant E)
Capital Cost (adjusted to 1977) 	 $1,100,000
     Annual Amortized Capital Cost @ 11% 	 $121,000

Operating Cost:

     Manpower:  2080 hr/yr @ $10/hr 	  $20,800

     Electrical Power:  149,000 kW-hr/yr x
                            $0.025/kW-hr	$ 3,700

     Maintenance Allowance  	  $15,000

Annual Operating Cost                                              $ 39,500

Total Annual Cost                                                  $160,500
          3
Cost per m  Treated                                                $0.23
                                                               ($1.03/1000 I.G.)
Cost per kg BOD  Removed                                           $0.077
                                                                  ($0.035/lb)
                                      23

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                                PLANT F
OXIDATION
OITCH  	

RAW
WASTEWA1
EQUALIZATION
TANK
'ER
                                       RETURN
                                     •— -,SL]JDGE_
                                          I
                                          I
                                          T

                                  WASTE SLUDGE TO
                                  SPRAY IRRIGATION OR
                                  SLUDGE DRYING BEDS
FIGURE 7 - SCHEMATIC FLOW SHEET OF WASTE TREATMENT PROCESS
           (PLANT F)
FINAL EFFLUENT
 TO RIVER
                                24

-------
             TABLE 11 - OPERATING AND DESIGN CRITERIA FOR
                        OXIDATION DITCH PROCESS (PLANT F)
Wastewater Characteristics:
     Flow:  Summer:     160 - 180 m3/day (35,000 - 40,000 Igpd)
            Winter:     45 - 55 m3/day (10,000 - 12,000 Igpd)
     Design Flow:       160 m /day (35,000 Igpd)
     BOD5:  Range:      500 - 1900 mg/L
            Average:    950 mg/L

     SS:    Range:      600 - 2500 mg/L
            Average:    1240 mg/L
Oxidation Ditch:

     Depth:             1.5 m (5 ft)
     Detention Time:    3.1 days
     MLSS Concentration:  4,000 mg/L
     Organic Loading:     0.076 kg BOD /kg MLSS/day
                                          3
     Volumetric Loading:  300 g BOD /day/m
                          (19 Ib BOD /1000 ft3/day)
                                                           3
     Aeration Requirements:  19 kW Cage Rotor  (21 kW/1000 m )
Clarifier:
     Diameter:            4.3 m  (14 ft)
     Overflow Rate:       11 m3/day/m2  (230 Igpd/ft )
                               25

-------
 Sludge is wasted from the process on a daily basis in summer  months by
 means of spray irrigation on 7.3 hectares (18 acres)  of  plant property.
 Sludge wasting occurs only intermittently in winter to sludge drying
 beds.

 The major problem encountered in operation of the  plant  has been  the
 loss of solids from the secondary clarifier due to flow  surges.   While
 the equalization tank provides some balancing of flow,  this is-insufficient
 to prevent the rising of the sludge blanket in the clarifier  and  subsequent
 loss of solids during extended periods of high flow.

 The clarifier design is such that settled sludge has  a tendency to cling
 to the conical sides and bottom.   This necessitates daily  scraping to
 remove the sludge and prevent problems of septicity and  denitrification
 from occurring.

 Some problems with ice formation on the aeration rotor have also  been
 encountered in winter operation.

 The oxidation ditch process  has performed very effectively with 99% BOD,-
 removal and 98%  removal of suspended  solids.   Average effluent concentrations
 of BODp and suspended solids are  7  mg/L and 28 mg/L,respectively.

 The plant  operator spends approximately one hour per  day maintaining the
 plant.   This  involves a daily sludge  settleability test, scraping of the
 clarifier  bottom and a weekly BOD,,  analysis.

 The waste  treatment plant was constructed in 1972  at  a cost of approximately
 $70,000.   As  shown in Table  12,  the updated value  of  the plant is estimated
 at  $110,000,  and annual operating costs at  $6,600.

 Plant  G

 Plant  G is  a  condensed milk  operation  that  processes  an average of
 approximately  159,000 kg  (350,000 Ibs)  of  raw milk per day.   Plant
 production  is  highly seasonal,  depending  upon availability of raw milk,
 although production is  generally carried  out  8  hours/day,  6 days/week.

 As  shown in Figure  8,  the waste treatment  process  employed by Plant G,
 consists of a  combined  extended aeration,  trickling filter process.  The
 average daily  flow  of  160 m^/day  (35,000  Igpd)  is  passed through a
 grease  trap and  screen  prior  to reaching  a  preaeration basin.   Wastewater
 from the preaeration cell is  pumped at  a  constant  rate of  38  L/s  (500
 Igpm)  to a  trickling  filter with rock media.   Underflow from  the trickling
 filter  is returned  to  the preaeration basin and  overflow from this cell
 enters  a second aerated cell, which carries a much higher concentration
of mixed liquor suspended solids.   Effluent from this stage in turn
passes  to a third aeration basin and finally  to a rectangular clarifier
prior  to discharge  to a municipal sewer.
                                     26

-------
         TABLE 12 - CAPITAL AND OPERATING COSTS FOR
                    OXIDATION DITCH PROCESS (PLANT F)
Capital Cost (adjusted to 1977)
     Annual Amortized Cost @ 11%
                                                   $110,000
                                                                 $12,100
Operating Costs:
     Manpower:  260 hrs/yr x $10/hr	$  2,600
     Electrical Power:  160,000 kW-hrs/yr x
                            $0.025/kW-hr  .
                                                   $  4,000
Annual Operating Cost
Total Annual Cost
                                                                 $6.600

                                                                 $18,700
Cost per m  Treated
                                                                 $0.32
                                                            ($1.46/1000 I.G.)
Cost per kg BOD,. Removed
                                                                 $0.35
                                                              ($0.16/lb)
                                     27

-------
                                RETURN SLUDGE
                                                     _WASJE_
                                                      SLUDGE
                                                           SPRAY IRRIGATION
                                                              OF SLUDGE
WASTEWATER
                                      FINAL
                                      EFFLUENT
               FIGURE 8  - SCHEMATIC FLOW SHEET OF WASTE
                           TREATMENT PROCESS (PLANT G)
                                   28

-------
Operating and design criteria for the plant are summarized in Table 13.
Sludge removed from the clarifier bottom is returned to the second
aeration basin.  In summer months, approximately 6.8 m^ (1,500 I.G.) of
return sludge are wasted per week by spraying on plant property.

Problems which have been encountered with the trickling filter include
ice buildup in winter months and some filter fly nuisance in summer.
Many problems have occurred with clogging of the carborundum type air
diffusers in the aeration basins.  This has necessitated daily brushing
and frequent removal of the diffusers to prevent excessive pressure
buildup in the aeration piping.

Discharges of high concentrations of suspended solids has been another
problem with the process.  Since the majority of the total daily flow
occurs in the last 3 hours of an 8 hour shift, during wash-up operations,
a flow surge occurs.  This results in increased overflow rates in the
secondary clarifier and the resultant loss of solids.

Approximately one hour per day is spent in maintaining the plant.  When
operating well, an effluent BOD concentration of less than 25 mg/L and
less than 100 mg/L of suspended solids is generally achieved.

An estimate of the capital cost of the waste treatment facility was not
available, but annual operating costs are estimated at approximately
$6,000 as shown in Table 14.

Plant H

Plant H is a 24 hour/day, 7 day/week milk processing operation.  The
main products are cheese and butter, with dried whey being sold as a by-
product.

The waste treatment facility consists of a 7-stage RBC unit followed by
aerated lagoons.  As shown in Figure 9, aqueous ammonia is added to the
flow equalization/preaeration basin ahead of the RBC unit, due to a
nitrogen deficiency in the waste.  Intermediate clarification follows
the first three stages of RBC treatment.  Effluent from the intermediate
clarifier is then further treated in an additional four RBC stages, and
discharged to a secondary clarifier.  Secondary clarifier effluent is
subsequently passed through a 2-cell aerated lagoon system, and a settling
basin prior to discharge.  The wastewater flow of 590 m^/day (130,000 Igpd)
is relatively consistent year-round.

Operating and design criteria for the waste treatment process are summarized
in Table 15.

The plant is maintained by one operator on a full time (8 hour/day, 5
day/week) basis, who monitors the process daily.
                                     29

-------
          TABLE 13  - OPERATING  AND  DESIGN  CRITERIA FOR  EXTENDED
                     AERATION/TRICKLING FILTER PROCESS  (PLANT G)
 Wastewater  Characteristics:
      Flow:      Range:     114 -  295 m3/day  (25,000 -  65,000  Igpd)
                Average:   160 m  /day  (35,000  Igpd)
     BOD  :     Range:     300 -  2,200 mg/L
               Average:   1,000  mg/L
     SS:       Range:     150 - 500 mg/L
               Average:   300 mg/L
Trickling Filter:

     Depth:              1.4 m  (4.5 ft)
     Diameter:           21.4 m  (70 ft)
     Organic Loading Rate:  320  g BOD /day/m3 (20 Ib BOD /1000 ft3/day)
                                   32           2
     Hydraulic Loading Rate: 0.44 m /day/m   (9 Igpd/ft )
     Media:              Rock
Extended Aeration Process:

     1st Cell:      Detention Time - 18 hours
     2nd Cell:      Detention Time - 15 hours
     3rd Cell:      Detention Time - 24 hours

Overall Aeration Requirements:
                    Diffused Aeration
                    (41 kW/1000 m3 of basin volume)
Secondary Clarifier:
                    Overflow Rate - 6.8 m3/day/m  (140 Igpd/ft )
                                   30

-------
              TABLE 14 - OPERATING COSTS FOR THE EXTENDED
                         AERATION/TRICKLING FILTER PROCESS (PLANT G)
Costs:
     Capital Cost	Not Available




     Operating Costs:


          Manpower:   260 hrs/yr x $10/hr 	   $2,600


          Electrical Power:  131,400 kW-hrs/yr x

                                $0,025/kW-hr 	   $3,300
     Annual Operating Cost                               $5,900
                                 31

-------
       10 DAY EMERGENCY

       HOLDING POND
                                          3 STAGE R8C
                                                               INTERMEDIATE
                                                                 CLARIFIER
 RAW
WASTE;
  AMMONIA
              PREAERATION/FLOW
              EQUALIZATION BASIN
                            SECONDARY
                             CLARIFIER
4 STAGE R8C
7
6
5
4


                                                       WASTE SLUDGE
                                                       8 DAY
                                                       AERATED
                                                       LAGOON
                                                                                   ,

                                                                              ^C
    WASTE
    SLUDGE
      SLUDGE

     ENTRIFUGE
   I
   I
   I
   Y
SLUDGE
DISPOSAL
                             10 DAY
                             SEDIMENTATION
                             8ASIN
                     FIGURE 9  - SCHEMATIC FLOW SHEET OF WASTE
                                TREATMENT PROCESS (PLANT H)
                                            32

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          TABLE 15 - OPERATING AND DESIGN CRITERIA FOR RBC/
                     AERATED LAGOON PROCESS (PLANT H)
Wastewater Characteristics:
                         3
Flow:
BOD :
SS:
                    590 m /day (130,000 Igpd)
                    3,400 mg/L
                    3,200 mg/L
                          - little variance
Preaeration/Flow Equalization Basin:
     Volume:        455 m3 (100,000 I.G.)
     Detention Time:  18 hours
First 3 RBC Stages:
     Surface Area per stage:
     Organic Loading Rate:
     Hydraulic Loading Rate:
           16,700 m2 (180,000 ft2)
           40 g/day/m2 (8.2 Ib BOD5/1000 ft2/day)
           0.012 m3/day/m2 (0.24 Igpd/ft2)
Intermediate Clarifier:
     Overflow Rate:
           36 m3/day/m2 (735 Igpd/ft2)
Last 4 RBC Stages:
     Surface Area per stage:
     Hydraulic Loading Rate:
           16,700 m2 (180,000 ft2)
           0.0088 m3/day/m2 (0.18 Igpd/ft2)
Secondary Clarifier:
     Overflow Rate:
           36 m3/day/m2 (735 Igpd/ft2)
Aerated Lagoons:
     First Cell:
Detention Time - 2 days
                             3                    3
Organic Loading - 320 g/day/m  (20 Ib BOD,/1000 ft /day)
     Second Cell:   Detention Time - 8 days

Aeration Requirements - Diffused Air with 3 blowers @ 75 kW each to aerate
                        preaeration basin plus both aerated lagoon cells
                      - Only one blower in use at present
                      - Average overall aeration requirements =
                        12 kW/1000 m3 (72 hp/MIG)

Final Settling Basin:    Detention Time - 10 days
                                     33

-------
 The RBC/aerated lagoon process has performed exceptionally well and
 demonstrated an ability to attain very high treatment efficiencies.   The
 RBC system with secondary clarifier is achieving approximately 90%
 removal of BOD  and 86% suspended solids removal.   Final effluent  from
 the aerated lagoon system contains less than 25 mg/L of  BOD  and suspended
 solids, for overall removals in excess of 99% for  both parameters.

 The major difficulty that has been encountered with the  operation  of
 this plant has been the handling of voluminous amounts of waste sludge
 produced by the RBC process.  Sludge collected from the  intermediate  and
 secondary clarifiers is dewatered in a centrifuge  and hauled  away  for
 spreading on 65 hectares (160 acres) of pasture land.  Approximately  9
 m-Vday (2,000 Igpd) of dewatered sludge must be disposed of in this
 fashion.

 As  shown in Table 16,  the estimated present value  of the plant is
 approximately $815,000.   It  was constructed in 1975 at a cost of $700,000.
 Operating costs are estimated at approximately $47,000 annually.

 FRUIT AND VEGETABLE PROCESSING PLANTS

 Plant I

 Plant I is a potato processing plant operating 24  hours/day,  5 to  6 days
 per  week.   It processes  an average 0.68 million kilograms (1.5 million
 pounds)  of potatoes per  day.
                                      3
 The  average wastewater flow  of 2800 m /day  (625,000 Igpd)  is  treated  by
 a high rate trickling  filter (biofilter)  process as illustrated in
 Figure 10.   In-plant pretreatment  processes consist of a mud  pit for
 removal  of field  stones,  dirt and  sprouts from the fluming water, a
 grease trap for removal  of free floating grease from the french fry
 operation,  and  scalping  and  vibrating screens  for  gross  solids removal
 from the combined wastewater stream.

 Screened wastewater is passed through a primary clarifier and then to
 two  high rate plastic  media  trickling filters  operated in series with
 interstage settling.   Effluent from the second trickling filter flows  to
 a secondary clarifier  prior  to discharge to a  river.   A  fraction of the
 final  effluent  is also recirculated to the  first trickling filter.

 Operating  and design criteria for  the plant are summarized in Table 17.

 Sludge removed from the  primary  clarifier is dewatered on  a vacuum
 filter prior  to being  hauled  some  18  km (11 miles)  to  a  lagoon for final
disposal.   Secondary sludge  is pumped directly to  a  dewatering and
digestion  lagoon located  on  the  premises.   Supernatant from this lagoon
is returned  to the  trickling  filters,  with  the dried sludge being removed
by means of a front end  loader  and  disposed of  on  land.
                                    34

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     TABLE 16 - CAPITAL AND OPERATING COST DATA FOR THE
                RBC/AERATED LAGOON PROCESS (PLANT H)
Capital Cost (adjusted to 1977) .......  $815,000
     Annual Amortized Capital Cost @ 11%  	  $89,700
Operating Costs:

     Manpower:  2080 hrs/yr x $10/hr  	  $21,000

     Electrical Power:
          980,000 kW-hr/yr x $0.025/kW-hr ....  $24,500

     Chemicals:	$ 1,400


Annual Operating Cost                                          $46,900


Total Annual Cost                                             $136,600
          3
Cost per m  Treated                                             $0.63
                                                          ($2.87/1000  I.G.)
Cost per kg BOD  Removed                                        $0.19
                                                             $0.085/lb)
                                    35

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    PROCESS WASTEWATER
                                   SCREENING^
                                   WASTE
        PRIMARY   \ SLUDGE  |  VACUUM
       CLARIFIER  I	*!  FILTER
  HAULED TO
  LAGOON FOR
  DISPOSAL
                                           SLUDGE
TO DIGESTION/
DEWATERING
LAGOON
                               FINAL EFFLUENT
FIGURE 10  - SCHEMATIC FLOW SHEET OF WASTE
             TREATMENT PROCESS (PLANT I)
                   36

-------
        TABLE 17 - OPERATING AND DESIGN CRITERIA FOR HIGH RATE
                   TRICKLING FILTER PROCESS (PLANT I)
Wastewater Characteristics:
     Flow:  Range:   2640 - 3050 m3/day (580,000 - 670,000 Igpd)
            Average: 2800 m /day (625,000 Igpd)
     BOD :  Range:   1700 - 4800 mg/L
            Average: 2,500 mg/L
     SS:    Range:   900 - 4200 mg/L
            Average: 2,000 mg/L

Primary Clarifier:
     Diameter:       20 m (65 ft)
     Overflow Rate:  9.8 m3/day/m2 (200 Igpd/ft2)

Trickling Filters:
     Dimensions: 12 m x 12 m x 6 m deep (40 ft x 40 ft x 20 ft deep) (each)
     Media:      Plastic Flocor
     Hydraulic Loading:  0.038 m3/day/m2 (0.78 Igpd/ft2)
                         (including recirculation)
     Organic Loading:    10,000 g/day/m3 (675 Ib BOD5/1000 ft3/day)
                         (first biofilter including recirculation)
     Recirculation Ratio:   1.6:1
Secondary Clarifier:        Diameter - 17 m (55 ft)
                                            37 m3/d
                                            (including recirculation)
Overflow Rate - 37 m3/day/m2 (750 Igpd/ft2)
Sludge Digestion/Dewatering Lagoon:
     Depth:          1.8 m (6 ft)
     Design Storage: 100 - 300 days
                                     2             2
     Design Solids Loading:  107 kg/m /yr (22 Ib/ft /yr)
                                    37

-------
 A number of operating problems were encountered with  the waste  treatment
 facility shortly after placing it  into operation  in 1971, but these have
 been largely overcome.   Grease and fibres  in  the  wastewater  caused a
 clogging problem with the spray nozzles on the biofilters necessitating
 their frequent cleaning.   A modified distribution system has been installed
 to alleviate this problem.

 Caustic  spills in the plant have occasionally resulted  in wastewater pH
 values in excess of  9.0.   These have caused damage to the biological
 film on  the media, which  requires  one to two  days to  recover.

 While the pH of  the  raw wastewater entering the primary clarifier is
 near neutral,  the primary sludge pH is usually in the range  of  4.3 to
 4.5 when removed.  This is  apparently due  to  biological activity within
 the sludge.   As  a result,  it was found necessary  to install  an  acid
 resistant cloth  on the  vacuum  filter  for satisfactory sludge dewatering.

 Experience has demonstrated that covers over  the  biofilters  would be
 useful in preventing  the  deposition of airborne leaves  and dirt on the
 media.   This would also assist in  retaining heat  lost during winter
 operation.

 The discharge  of  high concentrations  of suspended  solids in  the treatment
 plant  effluent was also encountered after  start-up.  Sodium  aluminate is
 now added to the waste  to promote  the development  of floes in the secondary
 clarifier and  improve sedimentation.   The  chemical is added  ahead of the
 second trickling  filter to  ensure  adequate  mixing.

 The high rate  trickling filter process has  performed effectively as a
 roughing unit, as intended,  and  has  achieved  relatively consistent BOD
 and suspended  solids  removals  of approximately 85%.  Final effluent
 concentrations of the two parameters  have  averaged 380  mg/L  and 280 mg/L,
 respectively.  Due to the high assimilative capacity of the  receiving
 stream to which the effluent from  this  plant  is discharged,  more stringent
 effluent  limitations  have not  been  required by regulatory agencies.

 The  plant performance is closely monitored  by five operators and a
 laboratory  technician,  with  suspended  solids  analyses made daily and
measured  two or three times  per week.

The  plant was  constructed in 1971 at  a  total  cost of $1,165,000.  The
updated  value  of the  plant  is  estimated  at  approximately $2.0 million
and  annual operating  costs at  $61,750,  as  shown in Table 18.
                                    38

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         TABLE 18 - PERFORMANCE AND COST DATA FOR HIGH RATE
                    TRICKLING FILTER PROCESS (PLANT I)
     Capital Cost (adjusted to 1977) 	  $2,000,000
          Annual Amortized Cost @ 11% 	  $220,000

Operating Costs:

     Manpower:  3,000 hrs/yr x $10/hr	$30-,000

     Electrical Power:  650,000 kW-hr/yr x $0.025/
                             kW-hr	$16,250

     Chemicals:   	$ 1,500

     Sludge Hauling:	, . .  $14,000


     Annual Operating Cost                                         $ 61,750

     Total Annual Cost                                             $281,750
               3
     Cost per m  Treated                                           $0.35
                                                              ($1.58/1000 I.G.)
     Cost per kg at BOD  Removal                                   $0.16
                                                                 ($0.074/lb)
                                      39

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 Plant J

 The wastewater from Plant J consists of effluent  from the processing of
 fresh fruit juices and sauces.   The principal products from the  plant
 are the following:

      1)   apple, pear, grape and apricot juices,  and  juice concentrates,

      2)   cherry,  peach,  apple,  raisin, and blueberry pie filling,

      3)   apple sauce,

      4)   citrus juices made from juice concentrates.

 The plant  operates 24  hours/day,  five days/week on  a  year round  basis.
 The daily  schedule consists of 16 hours of  processing followed by an
 eight hour clean-up shift.

 Wastewater from Plant  J flows to  an extended aeration treatment  facility
 which also handles the. wastewater from a winery and distilled liquor
 plant.  Although only  the cumulative flow data  for  the  two  plants were
 available,  the majority of  the wastewater is produced  by  the juice
 processing plant.

 The total-annual flow  to  the wastewater treatment plant is  approximately
 182,000 m   (40 MIG).   Monthly flows vary from 6,800 m   to  27,000 m
 (1.5-6  MIG) with large fluctuations occurring in  the  daily  flow  rate.

 A schematic of the extended aeration treatment  plant  is illustrated in
 Figure  11.  Effluent from the food  processing plant is  passed over a 40
 mesh  horizontal  vibrating screen  for coarse  solids  removal.  Prior to
 entering the wet-well  all wastewater is also passed through a 1.9 cm
 (3/4  inch) mesh  coarse screen.  In  the  wet-well provision has been made
 for the addition of nitrogen (aqua  ammonia)  and phosphorus  (phosphoric
 acid).  At  the present  time only  nitrogen is added; there  is sufficient
 phosphorus  from  the soaps  in the  cleaning water to  supply bacterial
 growth  requirements.   Recirculated  sludge is returned from  the secondary
 clarifiers  to  the  wet well  and mixed with the raw wastewater.  The
 aeration basin contains three 56  kW (75  hp)  mechanical surface aerators.

 Solids  are removed from the  mixed liquor  in  two 10.6 m  (35  ft) diameter
 clarifiers operated in parallel.  The clarified effluent is then chlorinated
 prior to discharge to  an  adjacent creek.  A  portion of the  sludge is
 returned to the  headworks of  the  plant while the remainder  is thickened
by centrifuging  and then  removed  by  tank  truck for  final disposal to
 land.   The centrate is returned to  the headworks of the plant.

Operating and design criteria for the plant  are outlined in Table 19.
                                     40

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      FOOD-PROCESSING WASTEWATER
                               VIBRATING SCREEN
                                     WINERY
                                     WASTEWATER
                                                              RETURN
                                                              SLUDGE
                                                       DISCHARGE
                                                           TO
                                                         CREEK
        SOLIDS  TO  TANK TRUCK
FIGURE  H      SCHEMATIC OF WASTEWATER TREATMENT PLANT
              (PLANT J)
                          41

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             TABLE 19  -  OPERATING AND  DESIGN  CRITERIA FOR
                        EXTENDED AERATION  PROCESS  (PLANT J)
Wastewater  Characteristics:
      Flow:   Range:
            340 - 1820 m /day (75,000 - 400,000 Igpd)
                 3
Average:    700 m /day (154,000 Igpd)
     Design Flow:
            2270 m /day (500,000 Igpd)
     BOD:
     SS:
            1,500 mg/L

              420 mg/L
Extended Aeration Process:
     Detention Time  (aeration basin)
     Aeration Basin Volume:
     Aeration Basin Depth:
     MLSS Concentration
                                8 days
                                5,675 m3 (1.25 MIG)
                                3.7 m (12 ft)
                                3,000 - 5,000  mg/L
     Organic Loading:
     Volumetric Loading:

     Solids Retention Time:
     Aeration Requirements:
                                0.05 kg BOD /kg MLSS/day
                                                3
                                184 g BOD /day/m
                                                     3
                                (11.5 Ib BOD5/1000 ft /day)
                                30 - 40 days
                                3 mechanical surface aerators @
                                56 kW ea. (30 kW/1000 m3 of
                                basin volume)
Clarifiers (2):
     Diameter:
     Overflow Rate:
     Sludge Wasting Rate:  1135 kg/day (2,500 Ib/day)
            11  m (35 ft)
                 32            2
            3.9 m /day/m   (80 Igpd/ft )  at average flow
                                     42

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Under present operating conditions the plant is achieving a BOD removal
efficiency of 99% and a suspended solids removal efficiency of 96%.
Effluent concentrations of the two parameters average 10 mg/L and 13
mg/L,respectively.

Operating problems were experienced initially due to ice formation on
the aerators during winter operation.  To alleviate this problem, warm
cooling water which is normally discharged directly to the creek is
diverted to the aeration basin during January and February.

Problems have also been encountered with the formation of floating
sludge in the secondary clarifiers.  This is caused by the adherance of
sludge to the thickener machinery for extended periods of time and has
been -most prevalent during the cherry processing season.

Problems of biological process stability have not occurred despite the
fact that the food processing plant only discharges wastewater five days
each week, and the daily loadings are highly variable.

Capital and operating costs for the wastewater treatment facility are
summarized in Table 20.  The plant was completed in 1973 at a cost of
$750,000 including land.  This corresponds to an estimated 1977 value of
$1,100,000.  The actual 1977 operating costs reported by the plant were
approximately $83,000, as shown.  The total annual cost and unit costs
of treatment are relatively high, considering the average wastewater
flow presently being treated at this plant.  This can be attributed to
two factors, as follows:

     1)   Since the plant was designed for an average flow rate
          considerably in excess of that presently being treated, the
          capital cost incurred in its construction was appreciably
          higher than would have been, had a smaller plant, designed
          only for the current average wastewater flow, been constructed.
          As a capital amortization cost allowance is included in the
          calculation of total annual cost, and subsequently in the
          calculation of unit treatment costs, these costs reflect this
          high construction expense.

     2)   The operating costs presented in Table 20 are those actually
          reported by plant personnel, rather than as calculated for
          previous plants, using simply the manpower and electrical
          requirements of the process.  Items such as the engineering
          cost allocation, and administration costs, which contribute
          significantly to the annual operating cost in this case, have
          not been estimated for other plants due to the highly variable
          nature of these costs from plant to plant and the obvious
          difficulty in attempting to derive a reliable estimate of
          this operating expense for each particular plant.
                                   43

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      TABLE 20 - CAPITAL AND OPERATING COSTS FOR EXTENDED
                 AERATION TREATMENT PROCESS  (PLANT J)
 Capital  Cost (adjusted to  1977)  	   $1,100,000
      Annual  Amortized  Cost @ 11%  	
      $121,000
Operating  Costs:

     Manpower:                           $27,800
     Electrical Power:                     7,800
     Equipment Maintenance:                4,000
     Sludge Handling                       1,200
     Plant Monitoring and Laboratory
       Analysis                            7,350
     Engineering Cost Allocation         13,800
     Administration                      15,000
     Miscellaneous                         6,000
Annual Operating Cost
      $ 82,950
Total Annual Cost
      $203,950
Cost per m  Treated
      $1.12
($5.10/1000  I.G.)
Cost per kg of BOD,. Removed
      $0.75
    ($0.34/lb)
                                   44

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Operational staff consists of a foreman who is also responsible for the
operation of the municipal sewage treatment plant, a full-time subforeman
and a plant operator who spends approximately 80% of his time at the
food-processing wastewater treatment plant.

Operation of the plant is monitored continuously with automatic samplers
and flow metering equipment.  Composite samples of influent and effluent
wastewater are collected daily and subjected to COD tests.  Temperature
and pH are monitored daily.  BOD and total suspended solids concentrations
are determined twice weekly and nutrient (N & P) concentrations in the
effluent are determined weekly.

Composite recirculated sludge samples are also collected regularly.
Total suspended solids are determined three times per week and volatile
suspended solids are determined twice weekly.  The data are used to
monitor sludge density to facilitate control of the sludge recirculation
rate, and to monitor sludge activity in order to control the mixed
liquor suspended solids concentration.

BEVERAGE INDUSTRY

Plant K

Plant K is a distillery which processes approximately 145 tonnes (160
tons) of corn, rye and barley malt per day on a 24 hour/day, 5
day/week basis.  The plant presently operates only seven months per
year.  Main products are beverage and industrial alcohol, with fusel oil
and high protein livestock feed material recovered as by-products.

Wastewater originates from equipment and floor washings, evaporator
condensate, boiler blowdown, gin still bottoms and rectifier bottoms.
The average daily flow of 908 m3 (200,000 I.G.) is discharged to a
45 m3 (10,000 I.G.) sump.  From here, two pumps controlled by level
switches lift the wastewater to the treatment plant.

Wastewater treatment consists of extended aeration followed by secondary
clarification and a polishing lagoon, as illustrated in Figure 12.
The operating and design criteria for the plant are summarized in Table 21.

Clarifier and lagoon effluents are monitored weekly by the plant operator
for COD and suspended solids.  A high quality effluent has generally
been achieved with removals in excess of 95% and 90% for these two
parameters respectively.  Effluent from the secondary clarifier generally
has a COD of less than 60 mg/L and this is further reduced to less than
50 mg/L in the lagoon.  The lagoon reduces the suspended solids concentration
in the clarifier effluent from approximately 20 mg/L to less than 15 mg/L.

Sludge is usually wasted on a monthly basis to drying beds located on
the plant property.
                                     45

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         PLANT WASTEWA-TER
    SUMP
NUTRIENT ADDITION
       AERATION

       BASIN
    SECOND*RY

    CLARIF1ER
                                   WASTE SLUDGE
                             SLUDGE
                             DRYING
                             BEDS
                   POLISHING

                       LAGOON
                    DISCHARGE TO RIVER
FIGURE 12 - SCHEMATIC  FLOW  SHEET OF WASTE
            TREATMENT  PROCESS  (PLANT :<}
                            46

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        TABLE 21 - OPERATING AND DESIGN CRITERIA FOR EXTENDED
                   AERATION/POLISHING LAGOON PROCESS (PLANT K)
Wastewater Characteristics:
     Flow:   Low:      23 m /day  (5,000 Igpd) - weekends

             Peak:     2050 m3/day (450,000 Igpd)
                             3
             Average:  1000 m /day (220,000 Igpd) - 5 days/week
     BOD:    Average approximately 800 mg/L
     COD:    1,000 - 1,500 mg/L
     SS:     200 - 300 mg/L
Extended Aeration Process:
     Organic Loading Rate:    0.16 kg BOD  /kg MLSS/day
                                                              n

     Volumetric Loading Rate: 800 g/day/m3 (50 Ib BOD5/1000 ft /day)
     MLSS Concentration:

     Detention Time:
2,000 - 8,000 mg/L

24 hours
     Aeration Requirements:   2 Mechanical Surface Aerators @ 19 kW ea.
                                          3
                              (4 kW/1000 m  of basin volume)
Polishing Lagoon:

     Depth:

     Detention Time:
1.2 m (4 ft)

5 days
                                  47

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 The wastewater has been found to be deficient in both nitrogen and
 phosphorus.   This is compensated for by a weekly addition of  45 kg
 (100 Ibs)  of urea and 23 kg (50 Ibs) of sodium dihydrogen phosphate  to
 the wastewater sump.

 It has been  found necessary to chip ice from around the  aerators during
 winter months.  Some freezing problems with the clarifier have also  been
 encountered  in cold weather.

 Since the  distillery is operated only seven months  per year,  the waste
 treatment  plant must be re-started  when production  commences.   The
 start-up period usually requires from 7 to 10 days,  although  in cold
 weather this may be extended  to 21  days.

 Plant operation is the responsibility of  a lab technologist, who spends
 approximately 4 to 5 hours  per week monitoring plant  performance and
 making adjustments as necessary.  An additional hour  per  week  is spent
 inspecting and lubricating  mechanical equipment and  adding  the necessary
 nutrients.

 As  shown in  Table 22,  the estimated present value of  the  plant is
 approximately $1,020,000.   It  was originally constructed  in 1969 at  a
 cost  of $490,000.   Annual operating costs are estimated at  approximately
 $7,500.

 FISH  PROCESSING INDUSTRY

 Plant L

 Plant L is a salmon processing plant that produces fresh, fresh-frozen
 and smoked-fish products.   In  addition  to salmon, the  plant processes
 aquaculture  fish,  primarily rainbow trout and immature salmon.   The
 salmon processing  season runs  for approximately six months  with  the
 processing of  aquaculture fish occurring  during the remaining  six months
 of the year.   The  plant operates on a 6-1/2 hour/day,  five  day per week
 schedule.

 Wastewater originates  as washwater  from fish cleaning  and gutting operations,
 and as  table  and  floor washdown water.  During  the salmon processing
 season,  flows  vary  from 1.4 to  4.5  m^/day (300  to 1,000 Igpd)  with an
 average  flow  rate of  2.6 m-Vday  (580 Igpd).  -While processing  aquaculture
 fish,  these  increase  to an average  of 13.6  m /day (3,000  Igpd).

 The wastewater  treatment system is  an extended  aeration process  as
 illustrated  in  Figure  13.  Raw wastewater  flows  to a wet-well  where
 grinder  pumps  lift  it  to an aeration basin.   Aeration  is provided by a
 3.7 kW  (5 hp) mechanical surface aerator.   Overflow from  the aeration
basin  then enters a  clarifier.  Settled sludge  is returned  to  the aeration
basin  from the  clarifier by means of  an air lift pump.  Clarified effluent
 is discharged  to a polishing pond which acts  as  an exfiltration  basin.
                                     48

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         TABLE 22 - CAPITAL AND OPERATING COSTS OF EXTENDED
                    AERATION/POLISHING LAGOON PROCESS (PLANT K)
Costs:
     Capital Cost (adjusted to 1977) 	   $1,020,000
          Annual Amortized Capital Cost @ 11% 	  $112,200
     Operating Costs:

          Manpower:  6 hrs/wk x 30 wks/yr x $10/hr  .  .  .   $1,800

          Chemicals (nutrients):  	   $1,000

          Electrical Power:  50 hp x 0.746 kW/hp x
                               5,040 hr/yr x $0.025/
                               kW-hr	$4,700


     Annual Operating Cost                                         $  7,500

     Total Annual Cost                                             $119,700
     Cost per m  Treated                                           $0.63
                                                               ($2.85/1000 I.G.)
     Cost per kg BOD  Removed                                      $0.79
                                                                 ($0.36/lb)
                                      49

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                        RAW CHARACTERISTICS
                         EXTENDED
                         AERATION
                         BASIN
                         CLAR1FIER
DISPOSAL OF EFFLUENT
TO POLISHING PONDS
SLUDGE
RETURN
                          SLUDGE DISPOSAL
   FIGURE 13  - SCHEMATIC FLOW DIAGRAM OF EXTENDED AERATION
               WASTE TREATMENT PROCESS (PLANT L)
                             50

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Table 23 summarizes design and operating criteria for the plant.

Wastewater flows have continuously been much lower than the design flows
during operation of the plant.  Although BOD removal efficiencies have
been within the acceptable range for an extended aeration system (i.e.
greater than 90%), suspended solids removal efficiencies have been less
than 65%.  Apparently this has resulted from the extremely long retention
times and overaeration of the mixed liquor.  This results in the auto-
oxidation of the biological floe, producing a pin-floe which is extremely
difficult to settle.

Other operational problems of the treatment system are listed below:

     1)   raw wastewater pumps periodically clog with fish bones or
          other coarse solids.

     2)   float level controls in the wet-well become caked with grease.

     3)   the scum removal system in the clarifier has been inadequate.

In addition, the wastewater usually contains a significant number of
fish eggs during the salmon processing season.  The cases from these
eggs become hard and cannot be broken down during the treatment process.

At the time of the field visit, an extended aeration pilot plant was
being used to establish optimum loading rates and aeration requirements.
Preliminary results have indicated that a 24 hour hydraulic detention
time is required to achieve adequate treatment.

The treatment plant was built in 1975 at a capital cost of $80,000.  The
updated value of the plant is estimated at $93,000.  It has not operated
continuously since that time, as the pilot plant studies currently
utilize most of the wastewater.  Operational costs for the large plant
have been minimal.  It does not employ an operator, although someone has
been responsible for periodically visiting the plant (approximately
three times weekly).  Since the plant has been relatively unused,
maintenance requirements have been very low.
                                   51

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             TABLE 23  -  OPERATING AND  DESIGN  CRITERIA FOR
                        EXTENDED AERATION PROCESS  (PLANT L)
                          Salmon Processing  Season
                              Aquaculture
                        Fish Processing Season
Wastewater Characteristics:
     Flow  (m  /day):
          Range:
          Average:
  1.4 - 4.5
     2.6
   7.7 - 18
     13.6
     BOD5  (mg/L)
     COD   (mg/L)
     SS    (mg/L)
     690
    2000
     500
      480
      810
      230
Extended Aeration Process:
     Aeration Time
     Volumetric Loading
     Aeration Requirements
   28 days
24 g BOD5/day/m3
 (1.5 Ib BOD5/
  1000 ft3/day)
  50 kW/1000 m3
 of basin volume
    5.5 days
86 g BOD./day/m3
  (5.4 Ib BOD5/
   1000 ft3/day)
   50 kW/1000 m3
  of basin volume
Clarifier:
     Overflow Rate

     Detention Time
 0.29 m3/day/m2
  (6 Igpd/ft2)
    4.3 days
      3      2
 1.5 m /day/m
  (31 Igpd/ft2)
    20 hours
                                     52

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 SUMMARY OF GENERAL OBSERVATIONS

 In reviewing the operation of biological waste treatment systems at the
 numerous food processing plants discussed in this paper, a number of
 recurring problems and industry concerns were identified.  These are
 as follows:

     1)   treatment plant supervision

     2)   flow equalization

     3)   sludge disposal

     4)   nutrient addition

     5)   winter operation

     6)   treatment costs.

 The above problem/concern areas warrant further discussion.

 Treatment Plant Supervision

 Without exception, it was found that the treatment plants operating most
 successfully were those which employed a trained, full-time operator.

 Due to the variable nature of food processing wastewaters, the potential
 for upset of a biological treatment system is relatively high.  Despite
 claims by a number of treatment equipment manufacturers and distributers,
 that their particular process operates with little or no supervision,
 very few biological treatment plants are truly capable of consistently
 producing an effluent of acceptable quality when treating a waste with
 highly variable flow and strength, without close supervision.

 This is particularly true of suspended growth systems (i.e. activated
 sludge, extended aeration, and oxidation ditch processes) where a number
 of problems, such as hydraulic or organic overloading, sludge bulking,
 or rising sludge in the secondary clarifier may develop over a relatively
 short period of time, resulting in a rapid deterioration in effluent
 quality.  These problems can only be overcome if a knowledgeable, full-
 time operator is on-site to identify them and take the appropriate
 corrective action.

A successful operator will be one who is completely familiar with the
 particular food processing plant and its associated wastewater character-
 istics.  In addition, he should be knowledgeable in the fundamentals of
 biological treatment and be aware of the potential operating problems
 associated with the specific treatment process, their causes and solutions.
 Finally, the treatment plant operator should be familiar with the maintenance
 and repair of all mechanical equipment, such as pumps, motors and compressors,
 upon which the successful operation of the plant relies.
                                     53

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 The operator should establish a daily schedule for monitoring  the primary
 physical, chemical and biological parameters  of the  process, enabling
 him to assess its performance and adjust operating conditions  accordingly.

 It is recognized that in the case of  very small food processing plants,
 economics may preclude the ability of the plant to retain a full-time
 treatment plant operator.   In such cases it is recommended that the
 potential for employing alternative methods of treatment and disposal,
 requiring considerably less supervision, such as joint municipal/industrial
 treatment be thoroughly investigated  prior to opting for on-site biological
 treatment.

 Flow Equalization

 In the course of conducting the site  visits discussed in this  paper, it
 became apparent that  the majority of  food processing plants operate on
 an 8 to 10  hour processing period per day, 5  or 6  days per week.  The
 majority of the daily wastewater flow generally occurs at the  end of
 this processing shift during the clean-up of  equipment, floors and
 tables,  and the dumping of the  contents  of product wash tanks, etc.
 Overnight and weekend flows are frequently negligible, made up largely
 of  relatively uncontaminated cooling  water.

 Many waste  treatment  facilities which are sized to handle the  average
 daily wastewater flow have difficulty providing adequate treatment for
 flow surges significantly  in excess of this average  flow.  This is
 particularly true of  some  components  of  the treatment process  such as
 secondary clarifiers,  whose performance  is so  dependent on flow-through
 velocity.   On the other hand, hydraulic  and organic  loadings significantly
 below the design rate frequently have a  deleterious  effect on  the biological
 reactor  stage of the  process.   The lack  of an  adequate food source for
 extended periods of time results in the  microorganisms entering an auto-
 oxidation growth phase in  which they  consume  their own cell protoplasm.
 This  in  turn results  in the development  of a  pin floe with poor settling
 characteristics.

 Both  problems  can be  alleviated by providing  sufficient storage capacity
 at  the front  end of the process to permit  the  flow surges to be temporarily
 held  back,  and  fed to  the  treatment plant during periods of low flow.

 Flow  equalization can  result  in significant improvements in effluent
 quality  from plants experiencing highly  variable hydraulic and organic
 loading  rates.   It can also  simplify  the  operation of the plant, and
 frequently  results in  lower  capital costs for  other  components of the
 treatment process, which can be confidently sized for the average waste-
water flow  rate,  rather  than making allowances  for peaking factors, etc.
                                    54

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One particularly effective means of providing flow equalization, which
has been demonstrated by the food processing industry, is the use of
anaerobic lagoons as the first stage in the treatment sequence.   If
properly designed, they can provide not only flow equalization,  but
pretreatment of the waste and an effective means of disposing and
digesting biological sludge produced in the subsequent aerobic treatment
steps.

Sludge Disposal

The amount of sludge which will be generated and which will require
subsequent treatment and disposal should be an important consideration
in selecting a waste treatment process.  At some of the plants visited,
sludge handling posed an enormous problem and constituted a major portion
of the annual operating cost.  These were generally plants at which
voluminous amounts of sludge were produced, requiring haulage to an
ultimate disposal site some distance away.

Those plants for which sludge handling posed relatively few problems
were the extended aeration type, which had very low sludge yields, and
those which had on-site sludge treatment and disposal facilities.

As discussed under flow equalization, anaerobic lagoons provide an
effective means of treating and disposing of biological sludge,  as well
as performing other functions.

In many cases, on-site sludge dewatering and disposal by means of drying
beds or spray irrigation also provides an effective and relatively
inexpensive means of handling partially stabilized sludges, such as
those from extended aeration plants.

In cases where insufficient land is available to permit on-site disposal
of sludges, one of the most important considerations in the selection of
a waste treatment process must be the amount of sludge generated by the
process and the cost of disposing of the same.

Nutrient Addition

A number of food processing wastewaters are known to be deficient in
either or both of the two nutrients, nitrogen and phosphorus, necessary
for effective biological treatment.  In some cases, these nutrients were
added continuously at controlled rates based on calculated requirements
determined from chemical analysis of the raw and treated waste.   However,
in other cases, nutrient addition amounted to the addition of "slugs" of
these chemicals to the waste on a weekly basis.
                                    55

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 The latter approach is not considered the optimum method  of nutrient
 addition.   Since the cost of purchasing these chemicals is relatively
 high,  and  the discharge of excessive amounts  of  nitrogen  and  phosphorus
 is undesirable from a regulatory agency's point  of view,  every  attempt
 should be  made to minimize the amount of supplementary nutrients  required.
 On the other hand, if the waste is  in fact nutrient deficient,  then it
 is important to ensure that adequate amounts  of  nitrogen  and  phosphorus
 are present at all times to permit  the microorganisms to  utilize  the
 soluble BOD  effectively.

 This can only be done by monitoring the BOD ,  nitrogen and phosphorus
 concentrations of the raw and treated wastes  on  a regular basis,  and
 adjusting  the rate of nutrient addition accordingly.  This is particularly
 important  in industry sectors where a variety of commodities  are  processed
 throughout the year,  such as  fruit  and vegetable processing.  As  the
 commodity  changes so  will  wastewater characteristics and  the  nutrient
 requirements.

 Winter  Operation

 Cold weather operation of  biological treatment systems poses  two  specific
 problems;  the  first being  a reduction in treatment  efficiency due to
 reduced  biological activity,  and  the second being  operational problems
 of  a mechanical  nature associated with freezing  conditions.

 To  ensure  treatment plant  performance conforms with regulatory agency
 requirements on  a year-round  basis,  it is  essential that  its design be
 based on the most adverse  conditions  under which  the plant will be
 expected to  perform.   Considering the highly  seasonal nature of most
 food processing  operations, the condition which  should be used for design
 purposes may be  either  peak hydraulic  and organic  loading or minimum
 operating  temperature  (or  both if the two occur  concurrently).  The plant
 size required  to  achieve the  desired  effluent quality under each operating
 condition  should  be determined and  the larger size selected for design
 purposes.

 The sensitivity of the  specific treatment process  to temperature effects
 should also  be considered  in  the selection of a  treatment system.  In
 general, suspended growth  systems such  as activated sludge, extended
 aeration and oxidation ditches have been found to maintain superior performance
 in cold weather to that of  trickling  filters and lagoons.

 Specific mechanical problems associated with winter operation were identified
at virtually all  plants visited, where  treatment units were exposed to
 the air.  Problems such as  the freezing of mechanical surface aerators,
 trickling filter media and distribution equipment, and skimming mechanisms
 in clarifiers were commonly reported.
                                      56

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Some of the following design features and operating methods should be
considered to alleviate these problems and improve treatment efficiency
in cases where treatment plants are expected to perform under severe
climatic conditions:

     1)   Wherever feasible, treatment units should be enclosed to
          minimize heat loss.  While this is obviously not feasible
          for large aeration basins, it is considered fundamental for
          the successful winter operation of trickling filters and
          clarifiers and is absolutely necessary for rotating biological
          contactors.

     2)   The use of diffused air aeration equipment in place of mechanical
          surface aerators can significantly reduce winter operating
          problems in open aeration basins.  The spray generated by surface
          aerators has a tendency to freeze onto aerator vanes, shrouds,
          and structural supports creating a heavy ice load which can
          lead to mechanical and/or structural failure of the equipment.
          This necessitates close supervision in winter months and
          frequent ice removal from the equipment.  Diffused air aeration
          equipment, being totally submerged, is not susceptible to these
          problems.

     3)   It is generally advisable to minimize the amount of wastewater
          requiring treatment, by diverting any uncontaminated flows
          away from the treatment facility for reuse or separate disposal.
          There may, however, be some advantage in winter months to
          directing hot uncontaminated wastewater flows, which normally
          by-pass the treatment plant, through the facility, thereby
          elevating its operating temperature.  Care must be taken, however,
          to ensure that this practice does not significantly reduce
          detention time in the plant, which may further reduce treatment
          efficiency.

Treatment Costs

The primary concern of any industry faced with the proposition of having
to install waste treatment facilities is the cost of constructing and
operating these facilities.

Unit treatment costs have been summarized for those plants for which
such data could be generated, and are presented in Figures 14 and 15 as
a function of plant size.  As explained earlier, the unit treatment
costs are based on the total annual cost which includes the annual
operating cost of the plant, plus an 11% annual amortization allowance
on the capital cost.

As illustrated in Figures 14 and 15, considerable scatter exists in the
cost data.  This scatter can be attributed to variations in wastewater
characteristics, treatment processes, and effluent qualities among the
plants considered, as well as other site specific variables such as
construction cost.

                                     57

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       '10
     $I.OO
o
°Q
_l UJ
< h-
Z> <
•Z. LU
2 P1
< H-
  ro
p-
      O.IO
                                 i^;_j_i_ 'i
                                           PLANT A
                                           PLANT B
                                           PLANT E
                                           PLANT F
                                           PLANT H
                                           PLANT I
                                           PLANT J
                                      •
                                      D
                                      »
                                      O
                                      •
                                      &
                                      A
                                          PLANT  K   0
             i i ry • i I •; • •!' J* i . i
ae±
                                                    .1
      O.OI
          100
                       ooo
                                                               10 000
                       AVERAGE WASTEWATER FLOW
                                (m3/DAY)
             FIGURE 14 - UNIT COST ($/mJ) OF BIOLOGICAL WASTEWATER
                       TREATMENT AT EIGHT FOOD PROCESSING PLANTS
                                 58

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       '10
H-
03
<
=5
<

<
O
LJ
UJ
     *I.OO
    10
O
CD
O>
      0.10
          100
PLANT  A
PLANT  B
PLANT  E
PLANT  F
PLANT  H
PLANT   I
PLANT  J
PLANT  K
                                                         D

                                                         O
                                                         A
                                                         0
              -4e-
                                                  rrz*.:
                                    I 000
               10,000
                      AVERAGE WASTEWATER FLOW
                                (m3/DAY)
                  FIGURE 15 - UNIT COST ($/kg BODs REMOVED)
                             OF  BIOLOGICAL WASTEWATER TREATMENT
                             AT  EIGHT FOOD PROCESSING PLANTS
                                 59

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Due  to  the number of variables associated with this cost data, no attempt
has  been made  to provide  the reader with a rigorous cost-effectiveness
analysis of  the alternative processes  investigated.  Rather, the data
will serve to  illustrate  the "order of magnitude" of these costs and the
trend of decreasing unit  treatment costs with increasing plant size.

CONCLUSIONS

Biological waste treatment facilities at the twelve food processing
plants  discussed in this  paper illustrate that such systems can perform
effectively  in northern climates if properly designed and operated.
Endeavours by senior management at these plants to meet their environmental
responsibilities have resulted in effective programs of wastewater
management.

Such wastewater management programs necessitate more than simply a
capital expenditure of funds for installation of an appropriate and
effective wastewater treatment system.  An ongoing commitment must be
made  to ensure that competent and trained operation of the process is
provided, and that in-plant measures are controlled so as to minimize
waste production and prevent treatment plant upsets.  Only if this
commitment is genuinely made can cost-effective operation of a wastewater
treatment facility be assured.
                                    60

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                THE UTILIZATION OF CHEESE WHEY
                     FOR WINE PRODUCTION

                              by

              G. M. Palmer* and R. F. Marquardt*
INTRODUCTION
In 1976 the United States Department of Agriculture (USDA)
reported production of nearly seventeen billion kilograms
(thirty-seven billion pounds) of whey in the United States
as by-products of the manufacture of cottage cheese and hard
cheeses such as cheddar, swiss, mozzarella, and jack.  USDA
estimated that seventy percent of that whey was processed
into food, food ingredients, lactose or animal feed; but that
thirty percent was not utilized.

The latter unutilized portion became either an environmental
pollutant - being sprayed onto wasteland or dumped into rivers
or streams - or an added consumer cost being cycled to
municipal wastewater treatment systems for purification.  It is
to the utilization of that currently unused portion of the
manufactured whey - sweet whey from the hard cheeses and acid
whey from cottage cheese - that this report addresses itself.

BACKGROUND

Much of the reason for the cited pollution from whey lies in the
economics of collecting it from small and/or isolated sources
for central manufacture into useful concentrated or dried
products by whey processors. To circumvent those economics and
to find a way to convert that whey into a useful and marketable
product at its source, Oregon State University (OSU) - working
under Environmental Protection Agency (EPA) Grant No. 803301 -
demonstrated the technical feasibility of fermenting supplemented
whey into an alcoholic beverage.  That grant was entitled,
"Utilization of Cheese Whey for Wine Production."

Based on the successful completion of that work, Foremost Foods
Company was granted Project No. S-8038-63010 entitled, "A
Demonstration Project on the Utilization of Cheese Whey for
Wine Production."
*Foremost Foods Company, Research and Development Center,
 Dublin, California
                               61

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OBJECTIVE

The  objective  of  the Foremost project is to demonstrate the
technical  and  commercial  feasibility of producing a consumer
acceptable,  fermented beverage  from whey.  Understood, of
course,  is a significant  reduction in environmental pollution
and/or waste treatment  costs.

RESULTS

To meet  the  objective,  Foremost Foods Company, Research and
Development  Center, developed processing to convert either
sweet or acid wheys into  an alcoholic beverage giving little
or no hint in  its flavor  as to  its origin in whey.  A natural
fruit flavored beverage was developed from this base, and small
scale consumer testing  demonstrated parity acceptance when
compared to  a market leader in  the fruit flavored wine class.
Preliminary  process costs indicate the beverage can be
competitive  in the market place.  Materials balance studies
demonstrated that the waste, measured in terms of BOD, from
the  fermentation process was significantly less than the BOD
which would  have resulted from disposal of the whey without
fermentation.

It was demonstrated early that sweet whey or acid whey yielded
to processing in similar manner.  Because the greater need for
whey utilization existed within the acid whey area, a major
portion of our efforts were directed to acid whey; although,
with nominal variation, they apply to sweet whey as well.

The processing from whey to a finished flavored product requires

      1.  Clarification of the whey

      2.  Deproteinization of the whey

      3.  Supplementation to a fermentable medium

      4.  Fermentation

      5.  Clarification of the ferment

      6.  Demineralization

      7.  Formulation

      8.  Polishing Filtration

      9.  Carbonation
                               62

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DISCUSSION

Processing

Let me discuss the process steps one by one, including our
experiences along the way.

Clarification of the whey is required to provide a whey that
is suitable for the selected deproteinization process.  It is
accomplished readily with centrifugal clarifiers and separators
common to cheese manufacturing.

As a process step, it removes the fine cheese curds entrained
in the whey as it is drawn off the cheese vat and the butterfat
that is not entrapped in the cheese curd mass.  This material
can be re-cycled in the cheese operation in various ways,
processed for other food use or routed to animal feeding
operations in its concentrated form.

Once clarified, the whey is deproteinized; not by heat or
chemical methods which denature the protein, but by ultra-
filtration which preserves the protein in its native form.

Ultrafiltration depends upon passing all but protein molecules
in the whey through a semi-permeable membrane to yield a water-
clear, deproteinized whey permeate as a fermentation base.
About ninety percent of the whey volume is passed as permeate
when the protein is concentrated to fifty percent on the dry
solids basis as the by-product.  The whey protein concentrate
is suitable for many food applications or for animal feeding.
Several ultrafiltration systems, now commercial in various
sizes, are satisfactory for this processing step.

Supplementation of the whey permeate is accomplished simply by
adding a small amount of potassium meta-bisulfite as a yeast
protector and stimulant and twenty-two percent of dextrose as
a fermentable carbohydrate.  Further supplementation is  not
needed as the whey provides the essential nutrients for yeast
growth and fermentation.

Based upon the results of the early study by OSU, we elected to
utilize the yeast Saccharomyces cerevisiae sub sp. ellipsoideus,
Montrachet strain as our fermenting organism throughout the
study.  This yeast, provided to the substrate in commercially
available active dry form, fermented the medium to a final
alcohol content of ten percent in seven to ten days at twenty-
one degrees Celsius (70 F) or ambient temperature.

The alcohol is derived by fermentation of the added dextrose,
the lactose present in the whey not being fermented by the
selected wine yeast.  To ferment the lactose would have required


                               63

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 fermentation by another type of yeast,  followed  by  supplemen-
 tation with dextrose and addition of the Montrachet yeast.  A
 lactose fermenting yeast currently is not available in  a
 commercial form,  as is the Montrachet yeast,  and would  require
 pure culture microbiology to maintain and bring  up  innocula
 for the fermentation.   To keep the processing simple and
 readily manageable, we elected to not ferment the lactose, but
 keep it intact to provide sweetening and enhance the flavor in
 the final product.

 In the initial stage of fermentation, we provided slow,
 stirring agitation in stainless steel dairy processing  tanks
 equipped with propeller agitators of the sweep variety.  This
 provided only enough agitation to keep  the yeast suspended
 until  active fermentation began.    Once actively fermenting,
 the yeast is kept in suspension by the  active bubbling  of
 carbon dioxide generated by the yeast.

 Clarification by  centrifugal or filtration methods  removes the
 yeast  bio-mass from the ferment and readies it for  further
 processing.   We found  that the preferred method  was  centrifugal
 clarification,  to remove the major portion of the cellular
 material,  followed by  pressure filtration, using a  diatomaceous
 earth  filter aid,  to remove the remainder; resulting in a water-
 clear,  fermented  beverage base.

 The ferment  -  or  beverage base -  at this  point in its manufac-
 ture is  predominantly  salty in taste with a definite whey
 flavor.   Attempting to formulate  a fruit  flavored beverage
 from this  base led  to  poor results according  to  informal
 sensory  panels.   It was  resolved  that the saltiness  must be
 removed  to develop  an  acceptable  beverage.

 Two  unit processes  known to remove minerals from fluid  streams
 were evaluated; these  are ion exchange  and electrodialysis.
 Ion  exchange is well known in many industries  as a   demineral-
 izing process;  on the  other hand,  electrodialysis is not, but
 it  is the  basis of  manufacture of  a series of  modified whey
 products widely used in  the food,  confection,  and baking
 industries and  is a technology utilized by the whey  industry.

 Testing  both processes, we looked  at the  advantages  and dis-
 advantages of  demineralizing before or  after  fermentation.  Ion
 exchange before fermentation removed the  saltiness but depleted
 the medium of  essential nutrients  to the  point of inhibiting
 seriously  the  fermentation,  whereas  electrodialysis  to about
 seventy  percent ash removal  reduced the  saltiness markedly
but  did  not  inhibit fermentation.   On the  other hand, ion
 exchange after fermentation  removed not only  the saltiness,
but  the unpleasant whey flavors as well; whereas electrodialysis
                               64

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performed less well in removing the whey flavors.

Based on those results, we chose to demineralize after fermen-
tation using an ion exchange system comprised of a strong acid
cation exchanger and a weak base de-acidifier.   Although not
tested, it is believed on the basis of other experience - that
activated carbon would effectively remove the whey flavors
if electrodialysis was utilized as a demineralizing method
instead of ion exchange

At this point in the process development, the flavor by mouth
attribute of the beverage base is predominantly alcohol, with
slight sweet and acid notes; a good base to accept flavoring.

We surveyed several versions of natural fruit flavors provided
by a number of flavor suppliers as compatible with our
beverage base.  Comparing those flavors in our beverage base to
the fruit flavored commercial wines, we selected a black
currant flavor extract with other natural flavors for our
beverage.  Working with the supplier, three adjustments to the
base flavor system were required before we were satisfied that
our target was met.

Formulation studies with the several versions of the selected
flavor system comprised variations in sweetening level, acid
level, flavor level and carbonation level.

The current formulation developed for acceptance panel testing
is characterized as follows:

      Demineralized Ferment Base        75.9%

      Invert Syrup                       6.26%

      Malic Acid                         0.236%

      Flavor Extract                     2.42%

      Water to Standardize              15.2%

This formulation, based on our acid whey fermented beverage base,
provided an acceptable approximation to the commercial target
wine in terms of the various flavor notes and overall balance
of flavor.

The next to final processing step is a polishing filtration.
This is accomplished using a microporous membrane filter
similar to those used for cold sterilization processing.  As a
processing step, it removes the extremely fine particulates
from the wine, which cause haze and sediment, and gives a fine
                               65

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 sparkle to the appearance of the beverage.

 Finally,  the beverage is  chilled,  carbonated  to  two volumes of
 carbon dioxide and bottled ready for  consumption.

 Sensory Evaluation

 This  study was monitored  throughout by  extensive use of four
 sensory evaluation technics:

       1.   Informal Panels

       2.   Descriptive Flavor Analysis (DFA)

       3.   Discriminatory  Panels

       4.   Small Scale Acceptance Panels

 The informal panels were  used early in  the study to screen
 processing and flavoring  systems and  select the  more feasible
 alternatives.

 Descriptive flavor analysis  characterized the aroma and flavor
 of the commercial  wine and of experimental preparations, to
 help  adjust processing and formulation  toward the target.
 This  technic uses  trained panelists to  quantify  aroma and flavor
 in terms  of key components and develop  flavor profiles which
 describes  the product under  test.  It proved very helpful in
 identifying off-flavor constituents in  the early part of the
 study  which aided  their elimination by  processing; and in
 adjusting  formulation variables  to approximate the profile of
 the target wine.

 Discriminative  panels, consisting of Research Center personnel,
 assisted  in adjusting formulation by rating both the
 experimental  products  and  the target wine in terms of too much
 or too  little of a flavor  component.

Acceptance panels  were used when other  sensory evaluations
 indicated  that  we  had approximated the  target wine in terms of
 critical flavor constituents  and balance.  Results indicated
 that in the  eyes of the consumer as well as our  in-house panels,
we had approximated closely  the  target wine flavoring balance -
although the  flavors  differed -  by advising that the test and
 target products were  equally  acceptable.

Economics  and Waste

The major  portion  of  this  presentation has been  devoted to
reviewing  the development  of  processing procedures needed to
produce an  acceptable product.   Economic and waste abatement


                               66

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aspects were important portions of the study and were
considered throughout the product and process development.
Final cost and material balances are not complete at this
writing, but preliminary estimates - considered with those
projections resulting from the OSU study - indicate a process
and ingredient cost of fifty to sixty cents a fifth of a
gallon.  Material balances show that the BOD of waste streams
from the process can be less than twenty-five percent of the
BOD of the whey itself.

CONCLUSION

At this writing, a large scale consumer evaluation in the form
of acceptance panels is being completed in east coast, midwest,
and west coast locations to answer the question of commercial
parity in the acceptance of the fermented whey beverage as
against a market leader in the flavored wine class.  Those
results, together with the results reported or indicated here,
will bear the proof of successfully meeting the challenge
of converting cheese whey and cottage cheese whey into an
alcoholic beverage acceptable in the market places of the
United States.

Collectively, they will provide the cheesemaker an interesting
and economic alternative to whey disposal as currently
practiced, and provide the means to reduce environmental
pollution due to whey.
                             67

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                    TREATMENT OF CAUSTIC  PIMIENTO WASTEWATER
                                       by
                                      JL              4.4.
                           T.M.  Furlow and  P.  Chen
  FOREWARD

  The caustic wastewater  treatment system discussed here was constructed over
  a  three month period  and started receiving wastewater in early August, 1977,
  Due to the light production and other construction conditions during 1977,
  this system was not fully evaluated during 1977.

  BACKGROUND

  Nabisco, Incorporated operates a food processing plant in Woodbury, Georgia
  approximately fifty-five miles southwest of Atlanta.  This facility produces
  roasted peanuts, peanut butter and packaged dates year round, and canned
  pimientos during August, September and October of each year.  Wastewater
  flows average around  380 M^/day (0.1 mgd) except during pimiento season when
  average flows increase sharply to 2270 M^/day (0.6 mgd).  Characteristics of
  the raw wastewater during 1976 are shown in Table 1.  The pimiento season
 wastewater is much stronger than the non-pimiento season wastewater, and is
  produced in much greater quantities.  When Nabisco considered separate waste-
 water treatment facilities in 1973, several processes were examined.  The
  final alternatives were activated sludge and overland flow (land application).
 Due to the large seasonal variation in both quantity and strength of the
 wastewater, and the availability of sufficient land, overland flow was
 selected.   A fifty acre site was prepared and placed into operation.  This
 system is shown in Figure 1.  All wastewater was screened before being pumped
 onto the spray field.   The system functioned well until 1975 when the runoff
  from the spray  field started to increase in strength.  Much of the grass
 died,  and waterlogging of the soil was observed.  By the end of the season
 it was obvious that corrective measures were necessary.

 DEFINITION OF PROBLEM

 Prior to 1975, all pimientos were peeled by a fire roasting process fueled by
 natural gas.   Interruptions in the supply of natural gas forced Nabisco to
 institute  caustic peeling of pimientos midway through the 1975 season.

 In February of 1976, Jordan, Jones and Goulding, Inc. was retained to study
 the system and to determine the cause of the previous season's difficulties.
 A ten  month study program was initiated which included an in-depth sampling
 program during the 1976 pimiento season.   The precise problems were found to
 * Jordan, Jones and Goulding, Inc., Atlanta, Georgia
** Nabisco, Inc., East Hanover, New Jersey
                                       68

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                         TABLE 1. AVERAGE CHARACTERISTICS OF RAW WASTEWATER
              Characteristic
VO
Suspended Solids




Total Volatile Suspended Solids




PH




Flow
Non-Pimiento Season




   1600 mg/1




    170 mg/1




    140 mg/1




      9.4
Pimiento Season




3450 mg/1




 540 mg/1




 480 mg/1




   11.5
                                                        380  M3/day (0.1 mgd)   2270 M3/day (0.6 mgd)

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    PUMP STATION
                   1
      SCREENS
  SPRAY FIELD
   PUMP STATION
  SPRAY  FIELD
4	1      SEQUILIZATION
           BASIN
  FLOW

  MEASURING
Figure  I.  Treatment  facilities
           prior  to  1977.
                     70

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be anaerobic  conditions.  The waterlogging of the soil and the reduced infil-
trative  capacity were  found to be directly related causes of the anaerobic
conditions.   Two Sodium Absorption Ratio  (SAR) tests run on caustic waste-
water samples gave results of 43 and 274.  This indicated probable defloccu-
lation of  the clay soil and sealing of the soil surface. Infiltration tests
revealed that the infiltration rate in irrigated areas had been reduced to
zero; the  infiltration rate in buffer zones was measured to be 1.9 centi-
meters per hour (0.75  inches per hour).   It was also noted that the high
solids loading was physically clogging the soil pores.  The BOD,, loading rate
to the spray  field increased to over 650 kg/hectare/day (580 Ibs/acre/day) at
an application rate of 2.16 cm/day (0.85  inches per day).  The literature
reports  success up to  112 kg/hectare/day  (100 pounds per acre per day) of
BODij loading.  Wastewater which had not been retained in the flow equalization
basin was  often irrigated directly onto the spray field.  The pH of this
wastewater was usually in the range between 12.0 and 12.5, and damaged the
grass in several areas.  Wastewater which had been retained in the flow equa-
lization basin had a pH of approximately  5.0.  The detention time in the flow
equalization  basin was only 12 to 24 hours, but very rapid pH changes were
evident.   In  an attempt to duplicate the  pH change, raw wastewater samples
were collected and seeded with varying volumes of pond effluent.  This mixture
was then adjusted to 11.5 with NaOH.  Within one hour, the pH of the mixture
was 5.1.   The cause of this rapid change has been attributed to aerobic
fermentation, although acid forming bacteria were likely present in the sludge
in the bottom of the pond.

The study  concluded that the problems encountered during the 1975 and 1976
pimiento seasons were  caused not by one factor, but by a combination of the
factors  discussed above.  It was further  concluded that wastewater with the
present  caustic characteristics was not ammenable to treatment by the
existing land application system.

DEVELOPMENT OF TREATMENT ALTERNATIVES

After determining that caustic wastewater was not suitable for treatment by
land application, several courses of action were available.

(1)   Change  the characteristics of the wastewater by process changes;
(2)   Abandon the existing overland flow  system, and develop a new
      treatment process;
(3)   Segregate the wastewater originating in the caustic peeling process,
      and  treat it independently of the rest of the wastewater.

The first  did not prove feasible because management determined that NaOH was
the only practical peeling agent.  The second course of action was feasible
but, because of the large existing capital outlay,was more expensive than the
third.   The wastewater originating in the caustic peeling operation could
be easily  segregated,  and constituted less than 10% of the total flow.  It
was therefore determined that the third alternative would be selected.

Before treatment processes for the caustic wastewater could be formulated,
it was necessary to characterize this particular portion of the wastewater
stream.  Sampling and  flow measurement results are presented in Table 2.

                                      71

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        TABLE 2.  CHARACTER OF CAUSTIC PIMIENTO WASTEWATER
BOD5                                             20,000 mg/l




COD                                              35,000 mg/1




Suspended Solids                                 16,000 mg/1




Total Volatile Suspended Solids                  13,500 mg/1




pH                                                   12



Flow                                             245 M3/day (0.065 mgd)

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The exceptionally high BOD_ and COD values indicated that an aerobic treatment
system would require a high energy input.  For this reason, initial considera-
tions were directed at non-aerobic processes.  One alternative was to use an-
aerobic ponds.  These could not be located close to the production facilities.
Tank trucks could be used to transport 246 M^/day (0.065 mgd) of caustic
wastewater to a suitable site during pimiento season.  Another alternative
was to use an activated sludge process.  This alternative, however, was not
feasible due to the seasonal production of the caustic wastewater.  Finally,
consideration was redirected toward aerobic processes despite the high energy
requirements.  Aerated ponds with long detention times appeared promising
since suitable land was available.  Recent work in North Carolina (1)
indicated that the energy input could be minimi zed if aerobic/anaerobic
ponds were utilized.  In the several systems in operation in North Carolina,
floating aerators with special deflector plates aerate only the top four
or five feet, thus creating sharp, distinctive aerobic and anaerobic layers.
The aerobic surface layer retards odors and allows use of the anaerobic
process in areas where anaerobic ponds might otherwise be unacceptable.

Preliminary cost estimates were prepared and the workability of each alter-
native was evaluated.  The aerobic/anaerobic pond alternative was selected.
The capital cost of the anaerobic pond system was considerably less, but it
was felt that transporting the wastewater by truck on a continuous basis was
not a workable solution.

SELECTED SYSTEM

The aerobic/anaerobic system selected consists of three aerated ponds followed
by a package sand filter, flow measurement, and a back up pH adjustment system,
as shown in Figure 2.

The first pond is 15 feet deep and is designed to provide an aerobic layer
approximately 1.2 to 1.5 meters (4 to 5 feet) deep, with the lower 3.0 to
3.4 meters (10 to 11 feet) being anaerobic.  The detention time is 52 days
at design flow.  Table 3 gives detailed information on all three ponds.

The second pond is a complete mix basin with a 10 day detention time.  Its
primary purpose is to insure that all of the wastewater is aerobic before
it is discharged into pond three.

The third pond serves as a holding pond and allows the wastewater to be
discharged over the entire year.  Two submersible pumps controlled by time
clocks regulate the discharge rate from this pond.  The floating aerators
are intended to be used only when the water depth in this pond is greater
than six feet.

The discharge from pond three is pumped into a package sand filter to insure
that suspended solids from the pond are low enough to comply with EPA re-
quirements.  Alum can be added as a coagulant prior to filtration when
necessary.

A backup pH adjustment system is also included which can adjust pH at either
the influent to pond one, or the effluent from pond three.

                                      73

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                          SCREENS
                         PUMP STATION

                         STAND BY P H
                        'ADJUSTMENT
                         AEROBIC

                         ANAEROBIC

                         POND  SYSTEM
                         STAND BY pH

                        "ADJUSTMENT


                        FILTER
                        FLOW

                        MEASURING
Figure  2.
Co ustic   waste water
t reatment  facilities.
                  74

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                              TABLE  3.  POND DESIGN INFORMATION
         Expected BOD,.         Depth              Volume       Detention Time
Pond      Removal (%)        Meters  (feet)        M3(ft3)       	Days           Pond Type
                             _                                	      	  —

 1            80               4.6     (15)       12,800 (452,000)      52          Aerobic/Anaerobic

 2            50               2.4      (8)        2,460 ( 87,000)      10          Aerobic-Complete Mix

 3            80            0-4.6   (0-15)       26,000 (919,000)   One Season     Aerobic-Holding Basin

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Following the sand filter, the discharge is mixed with any runoff from the
spray field.  Flow is measured in a Parshall Flume prior to its discharge
into surface waters.

CONSTRUCTION AND INITIAL OPERATION

Construction on the caustic wastewater treatment facilities started in May
1977.  On the first day of the 1977 pimiento season, August 4th, the first
pond was placed into service.  In order to check the operation of the floating
aerators, the basins were partially filled with water.  Thus, test results
from the 1977 season are not totally representative of treatment levels the
system can produce.  BODc removal did exceed 80% in the first pond, but a
detailed evaluation of the remainder of the system was not possible during
the 1977 season.  It is anticipated that an in-depth study program will be
conducted during the 1978 season to further evaluate the operation of this
system.
                                 REFERENCES
1.    Humerick, F. J., Personal conversations
                                     76

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                 OVERLAND FLOW TREATMENT OF DUCK PROCESSING
                        WASTEWATER IN A COLD CLIMATE

                                     by

                           Lloyd H. Ketchum, Jr.*
 INTRODUCTION

 Highly skilled personnel for design and construction as well as operation of
 wastewater treatment plants for small slaughterhouses and poultry processing
 plants is generally not available.  These small slaughtering and processing
 operations account for a small fraction of the total slaughter, however,
 they do nevertheless make up a very large fraction of the total sites.  These
 small plants are generally located in rural areas close to the growing oper-
 ations and feed lots.

 There is a need, therefore, to develop treatment facilities which are easy
 to design, simple and inexpensive to construct, and which can produce high
 quality effluents using relatively unskilled operators.  In general, land is
 available since these plants are located in rural areas.  Being located in
 scattered rural areas, however, wastewaters are often discharged into small
 streams and rivers or directly into the ground water.  These wastes, if im-
 properly treated, can cause serious  degradation in water quality in these
 scattered rural areas.

 The objectives of the project discussed herein are summarized as follows:

     .To demonstrate the operation of an inexpensive wastewater treatment
      facility which will meet the 1983 National discharge limitations.

     .To evaluate the use of spray runoff irrigation in a cold climate.

     .To evaluate the effectiveness of batch chemical treatment directly in
      a lagoon for phosphate and suspended solids removal (including algae)
      and disinfection.

     .To develop basis of design for the proposed treatment system, and to
      present these design details sufficiently clear to allow their use
      by slaughterhouse operators with little technical assistance.

     .To present estimates of costs for treatment to allow economic compari-
      son of this system to.others capable of treating these type wastes.

The project is currently in progress and none of these objectives have been
completed.  Reported herein, however, are details of the design and construc-
*Assistant Professor of Civil Engineering, University of Notre Dame,
 Notre Dame, Indiana  46556
                                     77

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 tion of these facilities and winter operation of  the  spray runoff  irrigation
 plot.

 The project is being conducted at Culver Duck Farm, Inc.  near Middlebury,
 Indiana.   This is a completely new processing plant.   Processing was begun
 on November 10, 1977 at a rate of 200 ducks per day.   The current  rate  is
 about  4000 ducks per week,  the maximum which can  be grown indoors  during
 winter periods.  To date, approximately 70,000 ducks  have been processed.

 The plant has been designed to minimize water use, and includes the use of
 a vacuum evisceration system.   Wastewater volumes have been estimated at
 23 L/duck (6 gal/duck).  Current water use is unknown since the meter has
 not yet been installed.  Consumption appears to be considerably higher  than
 this estimate, primarily because production is much lower than the design
 capacity, which results in higher water use per duck, and the operators have
 concentrated on the processing operation and have not yet devoted  sufficient
 attention to water usage.   The overall effect is  discharge of relatively
 large  volumes of weak wastewaters.

 WASTEWATER TREATMENT SYSTEM

 Table  1 gives the basis of  design and a schematic diagram of the wastewater
 treatment system is shown in Figure 1.   A fine screen,  Rotostrainer, is used
 to  remove pin feathers, offal  and other solids which  may  be present in  the
 water  prior to discharge to the sewer.   A gravity grease  separator follows
 the fine  screen.   However,  heavy grease loads are not experienced  because
 of  the dry evisceration and the effectivenss of the fine  screen.   These
 solids are picked up by the vacuum system and conveyed  to holding  containers
 where  they are picked up by a  rendering service.

 Following this preliminary  treatment  in the plant, the  wastewater  flows to
 the pump  manhole  where it flows either into the storage lagoon or  is pumped
 directly  to  the spray runoff irrigation plot.  During periods of processing,
 the pumps may be  operated to apply  raw wastewater directly to the  spray run-
 off irrigation plots.   During  periods when no processing  occurs the pumps
 may be operated to discharge wastewater which has  undergone some  stabiliza-
 tion during  storage in the  storage  lagoon.   This  system has been designed to
 allow  the flexibility of either operation-    Both will  be utilized during
 various operating modes throughout  this study.

 Two  spray runoff  irrigation,   or overland  flow, plots are used to  allow two
 modes  of  operation under parallel conditions.  Each is  20 m wide by 80  m
 long (65  ft.  by  260 ft.), or 0.16 hectares  (0.39  acres) in area.   Loading
 rates  and cycle conditions will be  varied  during  the  study.  Current opera-
 tion results  in applying wastewaters  ten hours per day, five days  per week
 at  a rate  of  7.6  cm per week (3 inches/week).

 Traditional spray  runoff irrigation methods are only  suited for soils with
 low permeabilities.   This low  permeability  reduces contamination of ground
waters and allows  for  additional  treatment  either in  a  lagoon as used in
 this study, or by  recycle back to the plot  during periods  of low quality.
                                     78

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                    TABLE 1:  DESIGN BASIS
                            PART A
                            Process
Production

Operating Days


Live Weight


Waste Volume
3000 ducks/operating day

winter 2 d/week
summer 3 to 4 d/week

6.4 Ibs/duck
2.9 kg/duck

6 gal/duck
23 L/duck
                            PART B
                  Waste Treatment Facilities
Storage Lagoon
Overland Flow Plots
Batch Treatment Lagoon
0.46 MG
1740 m3

2 plots
65' x 260'     0.388 acres
20 m x 79 m    0.157 hectares
4 percent slope
applications 3 in/week
             7.6 cm/week

0.13 MG
490 m3
4 weeks storage*
*Based on summer production and 50% evapotranspiration loss
 on overland flow plot.
                             79

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WATER
SUPPLY
                          VACUUM
      PROCESS
      PLANT
 VACUUM
                     ROTOSTR&INER
GREASE TRAP
       STORAGE
                                  GRINDER
                                  PUMPS
                             PUMP
                             MANHOLE
                              OVERLAND FLOW
                  BATCH TREATMENT    INFILTRATION
     FIGURE 1: Wastewater Treatment System Schematic
                      80

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Therefore, only effluents meeting effluent limitations are discharged into
receiving streams or ground waters.  In areas where only permeable soils
exist, traditional spray runoff irrigation treatment is not possible.  This
study addressed this problem, and developed a method of treating wastewaters
by spray runoff irrigation techniques on relatively permeable soils.   The
Culver Duck Farm site, according to U.S. Soil Conservation Service data, is
located on a sandy loam (Oshtemo Series) with a permeability of 5 to  15 cm/h
(2 to 6 inches/hour) which is much greater than that of the clays normally
used for spray runoff irrigation.

To eliminate infiltration of the wastewater into the ground water at  this
site, a bentonite seal was constructed six inches below the top soil  which
was than carefully graded to provide a four percent slope.  This seal essen-
tially eliminates infiltration into the ground water, and all applied waste-
water, not lost by evapotranspiration, reaches the foot of the plot.   Figure
2 shows details of the construction of this spray runoff irrigation plot.

The batch treatment lagoon serves two primary functions.  First, all  ef-
fluents from the spray runoff irrigation site are collected until the lagoon
is full.  Laboratory jar test procedures are then completed to determine
needed chemical dosage for phosphorous and suspended solids reduction.
Using a floating mechanical aerator to provide mixing, alum is sprayed into
the mixing lagoon followed by a hypochlorate solution for disinfection.  Af-
ter an appropriate period of mixing, the aerator is shut off and the  solids
allowed to settle.  After appropriate analyses are conducted on the settled
lagoon supernatant, and these analyses indicate an effluent of sufficiently
high quality, the contents of the lagoon are discharged to the infiltration
lagoon.  If the lagoon supernatant has not met discharge limitations, its
contents can than be mixed and additional treatment provided.  The second
function of this lagoon is to collect wastewater which received inadequate
treatment during spray runoff irrigation.  This may occur during periods of
high rainfalls or during application under other unfavorable conditions.
These low quality effluents can than be returned to the storage lagoon for
treatment under more favorable conditions, thus preventing discharge  of poor
quality effluents.

MONITORING

Flow rates are monitored at three locations in the system and change in la-
goon water volumes allows calculation of average flows at two other points.
First, water pumped from the plant well water supply is measured to allow
determination of water consumption which can be compared to the number and
live weights of ducks processed.  Magnetic Flosensors available from Cole-
Parmer Instrument Co. equipped with a totalizer and flow rate indicator are
used in the grinder pump discharge lines to indicate flow rates to each of
the two spray runoff irrigation plots.  Effluents from these plots are
measured in a weir box using a 22-1/2° V-notch weir for low flows during
normal  conditions and a rectangular weir for high flows during rainfall
periods.  Both lagoons have been measured to allow determination of liquid
volumes between any depth, thus indicating average flows for any period of
time during which these depths are changing.


                                     81

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         /-DISTRIBUTOR  PIPE
      
-------
Wastewater analyses are conducted generally according to procedures outlined
in Standard Methods and include the following:  5-day BOD, TOC, pH, suspended
solids, ammonia, nitrate plus nitrite, Kjeldahl nitrogen, and ortho and total
phosphate.  These are generally taken at the influent and effluent end of
each unit.  In addition, temperature, dissolved oxygen, COD, oil and grease,
settleable solids and fecal colifonns will also occasionally be determined.

TEMPORARY FIRST WINTER OPERATION

During the construction and start up phases of the processing plant, a time
when we were also trying to complete construction of the wastewater treatment
facilities, considerable difficulties were encountered which demanded the at-
tention of the personnel assigned to both of these tasks.  This resulted in
delays in completion of the wastewater treatment system.  These delays ex-
tended into an unusually severe winter where record snowfalls occurred.  By
the end of December, we had already almost reached the average annual snow-
fall of 67 inches.  An additional 86 inches fell in January contributing to
a new record annual snowfall.

The control building, used mainly to house the flow measurement equipment,
was only partially completed before winter, thus preventing installation of
the flow measuring equipment.  The underground piping from the pump manhole
to the spray runoff irrigation distributor pipe was placed in the ditches.
However, before these could be backfilled the backfill material and the soil
in the ditch had frozen preventing completion of the backfill operation.
Several methods to allow temporary winter operation were considered.  The
method finally selected and installed which allowed for the operation re-
ported herein is described as follows:

     .A single grinder pump is operated continuously with discharge through
      one of the partially buried pipes.  This continuous flow prevents
      freezing of the exposed pipe.

     .A temporary pipe is connected to the partially buried pipe and runs
      above ground to and past the distributor pipe into a lagoon system
      used to treat wastewaters from the duck growing operation.

     .A three-valve connection is made between the temporary above ground
      pipe and the inlet to the distributor pipe of one plot.  These valves
      are arranged to allow restricted flow at all times through one valve
      into the lagoon.  During periods of spray runoff irrigation, a second
      valve is fully opened to direct flow into the distributor pipe.  The
      valve used to restrict flow to the lagoon is adjusted to provide the
      desired application rate to the spray runoff irrigation plot.  At the
      conclusion of an irrigation period, the second valve is closed and a
      third valve opened which drains the distributor pipe and prevents its
      freezing.

Influent flow rates are determined by recording the time required to fill a
known volume from each orifice in the distributor pipe.  The effluent from
the spray runoff irrigation plot is allowed to overflow the dike at the foot


                                     83

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 of the plot where it then passes through an earthen ditch and over a tempo-
 rary 45° V-notch weir.  Effluent flow rates are thus determined by measuring
 the depth of flow over the V-notch weir.

 Wastewaters were first applied on February 22,  1978.  At this time, there
 was about 23 cm (9 inches) of relatively densely packed snow covering the
 site.   At least two weeks passed before overflow of the dike occurred at  the
 foot of the plot.   Wastewater was applied as indicated above resulting in an
 application of approximately 7.6 cm per week (3 inches per week).   The snow
 had been removed from the area near the distributor pipe.   Applied wastewater
 appeared to flow down the slope under the snow and accumulate at the foot of
 the plot behind the dike.  At that point it froze.  Later, as melting oc-
 curred and additional water was applied, it overflowed the dike.  Snow was
 gradually lost from the plot until only about one half the area was covered
 with a layer of ice.   The idle plot, adjacent to the operating plot appeared
 to behave essentially the same.  Snow loss, flow over the dike and ice for-
 mation all appeared to be similar.

 One interesting observation was the grass which appeared to be a healthy
 green  in the areas not covered with snow or ice.

 RESULTS

 Occasional grab samples were taken from the influent and effluent  of the
 spray  runoff irrigation site after the  first two weeks  of  operations.   In
 general,  two influent  conditions  occurs.   One when pumping occurs  during
 processing which results in raw wastewater being applied to the plot,  and
 the  other when  no  processing is taking  place which results in water from  the
 storage lagoon  being pumped to  the plot.   In the first  case,  the influent
 wastewaters tended to  be relatively strong with 5-day BOD's greater than  100
 mg/L being common.  In the second case,  these wastewaters  were relatively
 weak having 5-day  BOD's between one-third and one-half  this level.   This  is
 due  partially  to the stabilization which takes  place in the lagoon but  also
 due  to  dilution during the early phases  of plant  start up when only a  few
 ducks  were being processed using  full process water flows.

 The  grab  sample effluents  from  the plot  were relatively weak showing 5-day
 BOD's  of  5 to 10 mg/L.   Dilution  from melting snow undoubtly contributed  to
 these  low values.

 Two detailed analyses  of the  influent and effluent of the  spray runoff  irri-
 gation  site  were completed.   One  of these was taken from samples collected
March  21,  1978  which was during a  duck processing  period,  therefore,  a  period
 of application  of  raw wastewater.   The other, March  22,  1978,  was  conducted
 during  a  day when  no processing took place  and  wastewater  from the  storage
 lagoon was being treated.   The  results of  these analyses are  shown  in Table
 2.  These  data  are taken from flow-weighted  composite samples  collected
 during  the period  of spray  runoff  irrigation  pumping.

A mass balance, based on the  average influent and  effluent  flow rates during
 the sample periods, and  the composite analyses  of  these waters  is  shown in


                                     84

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                     TABLE 2:   WASTEWATER CHARACTERISTICS
                                                  Overland Flow Plot
Influent Effluent
March 21, 1978 Sample
5-day BOD, mg/L
COD, mg/L
NO + NO , mg/L as N
NH , mg/L as N
Total Kjeldahl nitrogen, mg/L as N
Orthophosphate, mg/L as P
Total phosphate, mg/L as P
March 22, 1978 Sample
5-day BOD, mg/L
COD, mg/L
NO + NO , mg/L as N
NH3, mg/L as N
Total Kjeldahl nitrogen, mg/L as N
Orthophosphate, mg/L as P
Total phosphate, mg/L as P
PROCESSING
170
250
0
4
33
2.3
2.6
NO PROCESSING
93
230
0
3
23
0.3
0.6
DAY
7
80
0.01
4
10
0.7
0.6
DAY
24
45
0
3
3
1.2
1.3
in Table 3.  In general, it appears stabilization of organic matter is taking
place and nitrogen removal is occurring in spite of the ice and snow cover and
the relatively low temperatures.  Several other grab samples taken during the
two weeks preceding this study also indicated stabilization of organics and
nitrogen removal were taking place.  Table 4 has been included to indicate
weather conditions during the period of overland flow treatment.  Applica-
tion first began on February 22, 1978, and these detailed analyses were
taken a month later on March 21 and 22, 1978.  Due to the ice formation
during the previous 30 days of applications of wastewater, a considerable
amount of snow and ice remained on the plot and significant amount of melting
                                      85

-------
                            TABLE 3:  MASS  BALANCE
                                                PROCESSING DAY
March 21, 1978 Sample
Average Flow During Sample
Period L/s
5-day BOD, mg/s
COD, mg/s
NH , mg/s
Total Kjeldahl nitrogen, mg/s
Orthophosphate, mg/s
Total phosphate, mg/s
March 22, 1978 Sample
Average Flow During Sample
Period L/s
5-day BOD, mg/s
COD, mg/s
NH , mg/s
Total Kjeldahl nitrogen, mg/s
Orthophosphate, mg/s
Total phosphate, mg/s
Influent
0.42
71
105
1.7
14
1.0
1.1
NO
0.83
77
191
2.5
19
0.2
0.5
Effluent
0.62
4
50
2.5
6
0.4
0.4
PROCESSING
1.92
46
86
5.8
6
2.3
2.5
% Reduction
increased
94
52
increased
57
60
64
DAY
increased
40
55
increased
68
increased
increased
was occurring, as can be seen by the effluent flow rates.

DISCUSSION

To date, the findings have been very promising.  The use of the bentonite
layer below the top soil in the overland flow plot extends the possible ap-
plication of overland flow treatment to all areas of the country regardless
of soil conditions.  The bentonite layer further eliminates infiltration of
applied wastewater into the ground water during treatment.  Essentially all
water applied and not loss through evapotranspiration can be collected at
the foot of the hill for additional treatment or retreatment if it does not

                                    86

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                        TABLE 4:  WEATHER CONDITIONS*
Date
Feb. 22, 1978
23
24
25
26
27
28
Mar. 1, 1978
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
Average
Temp., °F
14
20
28
32
18
21
27
18
13
21
15
11
26
24
24
19
28
35
36
35
38
35
30
25
28
34
37
40
44
Precipitation, inches
Water Equivalent,
0
0.07
0
0.07
0.06
T
0
0
0.07
0.12
0.01
0
0
0
0
0
0
0.20
T
0.36
0.45
T
T
T
0
0.75
0.03
T
0
Snow
0
1.0
0
1.2
1.1
T
0
0
1.0
3.1
0.5
0
0
0
0
0
0
T
0
0
0.4
0.1
T
T
0
0
0
0
0
Snow on Ground
at 7 a.m., inches
17
16
17
15
16
16
15
14
13
16
15
15
15
13
12
12
11
9
8
7
6
4
4
3
3
2
1
T
T
   *Based on records collected at South Bend, Indiana,National Weather
    Service Office, Michiana Regional Airport, which is located about
    30 miles due west of the test site.
meet discharges limitations; thus, only fully treated wastes are discharged
to receiving water or ground surfaces for infiltration into the ground
waters.

The few operating results we currently have under winter conditions also ap-
pear favorable.  Stabilization of organics and nitrogen removal both appeared
to be occurring under cold climate conditions.  Thus, overland flow treat-
ment can be an alternative considered not only for areas of any soil condi-
tion, but even in areas of cold climate.

                                      87

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 Additional  phases  of  the  overland  flow  study will be directed toward develop-
 ment  of more  favorable  operating conditions during these winter periods.  One
 approach we plan to consider  is elimination of the use of storage before
 overland flow treatment.   Thus, we will apply the raw  (warm) wastewater
 during processing  operations.  In  our case, this is typically during two
 consecutive 10-hour day periods each week  during winter operations.  For
 other systems when operation  is more nearly continuous, we would propose
 several parallel operations sequenced to provide similar treatment.  The
 warm  raw wastewaters  would be applied to the overland flow plot and continu-
 ally  recycled from a  small lagoon  at the foot of the plot to the top until a
 suitable effluent  was obtained.  Other  operating and loading procedures will
 also  be considered to attempt to develop operating procedures to allow winter
 operation,  or to determine under what conditions winter operation must be
 discontinued  and storage  provided.
ACKNOWLEDGMENT

This project has been financed in part with Federal funds from the Environ-
mental Protection Agency under grant number R-804677.  The contents do not
necessarily reflect the views and policy of the Environmental Protection
Agency, nor does mention of trade names or commercial products constitute
endorsement or recommendation for use.
                                     88

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                    ECONOMICS OF STARCH AND ANIMAL FEED
                       PRODUCTION FROM CULL POTATOES*

                                     by
                                                             **
               J. R. Rosenau, L. F. Whitney, and J. R. Haight


ABSTRACT

A finalized process for production of starch and animal feed pulp, high pro-
tein powder, and juice concentrate from cull potatoes is presented.  Economic
evaluations are presented for the process and an option applicable if the
plant is located near a ruminant feedlot.

INTRODUCTION

Processes for upgrading cull potatoes to starch and animal feed by-products
have been discussed by the authors at previous symposia (1) (2).   By addi-
tional laboratory (3) and pilot plant experience (A), these processes have
been tuned to the finalized processes shown in Figs.l and 2 and briefly out-
lined below.  An economic evaluation follows which suggests that reasonable
returns on investment are possible even under recent dramatic price increases
in fuel and equipment (M & S Index of 518 as opposed to only 344 in 1973) (5).

STARCH PROCESSING

As shown in Fig. 1, cull potatoes are washed with recycled water and ground
with 250 ppm SO  in a hammer mill using a screen with 1.6 mm (1/16 inch)
openings.  The slurry is screened in a two-stage system with recycled juice.
Most of the cellulosic material (pulp) remains above the 140 mesh screen while
juice and starch pass through.  The pulp is dewatered in a screwpress and
dried in a continuous tray drier using waste heat from the juice processing
system.

The starch/juice slurry is pumped into an elutriating-type liquid cyclone
which has an extra inlet near the underflow outlet.  Starch is spun to the
underflow and the overflow juice recycled to the screening system.  Excess
juice is forwarded to the regenerative plate heat exchanger shown in Fig. 2.
 *This investigation has been supported by the U. S. Environmental Protection
  Agency (Grant No. R-803712-03-0), Agway, Inc., the Main Potato Commission,
  and the University of Massachusetts.

**Department of Food and Agricultural Engineering, University of Massachusetts,
  Amherst,  MA  01003.
                                      89

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     WASHED POTATOES
          GRINDER |
         | SIEVE
                  WET PULP
             PRESS )
            JUICE 8 STARCH
         [ TANK
          PUMP
  ELUT
CYCLONE
MECHANICAL
DEFOAMER
1

CAKE
CONTINUOUS
TRAY DRIER
                                                I
                                              PULP
r-Y
1
IP) IMP 1 &
t wlWI" 1 *•



CYCLONE
 PUMP  «
                        BASKET  CENTRIFUGE]
                               CAKE
                          j DRIER j

                              I
                           STARCH

           Figure 1.  Starch processing flowchart.
                         90

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 JUICE  (3.9% SOUPS)
       IO°C
PLATE HEAT EXCHANGER \
                         »9°C
       60°C
     INFUSERj
       I2I°C
 PLATE HEAT EXCHANGER^
       66°C
|  NOZZLE CENTRIFUGE
       SLUDGE, 20% SOLIDS
| SPRAY DRIER  |


        I
  PROTEIN POWDER

 (70% CRUDE PROTEIN, D.B.)
:THEAT EXCHANGE FLUID
  (TO a FROM PULP DRIERh
      REVERSE
      OSMOSIS
      EVAPORATOR
                                      T
                                   CONG. JUICE

                                   (65% SOLIDS, 43%
                                   CRUDE PROTEIN, O.B.)
         Figure 2.  Juice processing flowchart.

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           TABLE 1.   ESTIMATED FIXED  CAPITAL  INVESTMENT FOR
                     PROCESSING 500 TONS  OF CULL  POTATOES
                     PER 20-HOUR DAY
                ITEM
COST. $
COST, $
           Flume  pump
           Washer pump
           Washer
           Destoner
           Mill
           Metering feeder  for Na^S-O
           Sieve  system
           Mechanical defoamer
           Press
           Pulp drier
           Pulp mill
           Pulp air conv. system
           Pulp bins (2)
           Cyclone pumps  (5)
           Elut.  cyclones (8)
           Thick, cyclone pumps (5)
           Thick, cyclones  (4)
           Pump,  centrif. to cyclones
           Basket centrif.
           Starch drier
           Starch mill
           Starch conv. system
           Starch screen
           Plate heat exchanger
           steam  injector
           Boiler (12000 Ib/hr)
           Fuel tank
           Nozzle centrif.
           Spray drier
          Rev. osmosis modules
          Rev. osmosis feed pump
          Rev. osmosis cir. pumps (3)
           Evaporator
           Concentrate pumps (2)
          Concentrate tank
           Balance tanks (4)
          Protein bin
          Truck scale
   5000
   3000
  20000
  20000
  50000
   4000
  60000
  24700
  50000
  60000
  10000
   5300
  10000
  15000
   5600
  15000
    800
   1000
  98800
  16800
  10000
   5500
   6000
  20000
   2000
  25400
  16900
 100000
  23700
  87000
  15800
  12000
 118600
   8000
  16900
  25200
   5000
   9500
 I.    Total Process Equipment

II.    Installation (30% of I)
               982500

               294800
                                    92

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                            TABLE 1 (continued)
                  ITEM
 III.    Piping, Wiring, and Control Systems
         (40% of I and II)

  IV.    Engineering and Contractors' Fees
         (20% of I, II, and III)

   V.    Contingencies (15% of I, II, III)

  VI.    Trucks
         Concentrate truck
         Protein truck
         Pickup truck

 VII.    Land
         Office
         Incoming storage
         Process area
         Warehouse

VIII.    Buildings total
                                         COST, $
                                         70000
                                         40000
                                          7000
                                         35000
                                         63800
                                        168000
                                         60000
COST, $


510900


357600

268200

117000
                                                         40000
  IX.
TOTAL FIXED COSTS
                                      93

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 Starch leaving the underflow cyclone outlet is  thickened  with  a  second  liquid
 cyclone before passing to an automatic batch basket centrifuge for washing  and
 dewatering.   Liquid from the basket centrifuge  as well as that removed  by the
 thickening cyclone pass into the elutriation inlet  of  the first  cyclone to
 separate "brown starch" from the starch.   Attempts  to  eliminate  the  thickening
 cyclone or to add an elutraition inlet to it have not  proven as  successful  as
 the scheme shown.  Drying of the starch cake leaving the  centrifuge  should  be
 done in a flash drier for maximum whiteness.  Hunter L values  of 92  (which
 should be sufficiently white for most purposes)  have been consistently  achieved
 in later pilot plant runs even with very  low starch content potatoes  and drying
 in a tray drier at HOC.   Proper washing  of raw potatoes  is also important
 for maximum whiteness; an industrial washer,  coupled with finer  control of
 the elutriation flow rates,  should improve whiteness even further.

 JUICE PROCESSING

 As shown in  Fig.  2,  juice is heated to 60C in a plate-type regenerative heater
 and then to  121C  by steam  injection.  This  coagulates about  35% of  the crude
 juice protein so that it  can be removed as a  20% solids (70% protein, d.b.)
 sludge by a  nozzle-type disk centrifuge and dried in a spray drier.   The re-
 maining deproteinated juice  (still at 43% crude protein,  d.b.) is concentrated
 by reverse osmosis to 10% solids and by multiple-stage evaporation to 65%
 solids.   It  is stable in  this condition and should  be  useful as  a molasses
 substitute for ruminant feeding.

 ECONOMIC EVALUATION

 Estimated capital costs based on references (5)-(9), personal  estimates, and
 telephone calls  to selected  suppliers are shown in  Table  1.  Table 2  shows
 annual costs and  returns  assuming the plant is  run  for 200 days  for  20  hours
 per day.   Also shown is the  first-year  return on investment (R.O.I.)  at 40.1%.

 LIVESTOCK OPTION

 If  the processing center  is  located  near  a ruminant  feedlot of at least  2500
 dairy  cows or  its equivalent  (or  vice versa)  the pulp  and  concentrated  juice
 from  the  reverse  osmosis  system can  be  used directly without drying or  vacuum
 concentration.  The water in  the  concentrate  would be  substituted for the
 normal daily water intake of  15 gallons per animal.  The  concentrate would
 contain  all  the protein required  by  the animals.  The  pulp drier  and the
 vacuum evaporator  as well as   some ancillary  equipment are eliminated by this
 option which would require trucking  of  46  tons of wet  pulp and 140 tons of
 concentrated juice from the plant  to  the  feedlot daily.

 The cost  figures  for this  option  are  shown  in Tables 3  and 4 and yield  a
 43.9% R.O.I, under the  assumption  that  the  feedlot would pay for  the feed
values in the  pulp but  not for  that  in  the  concentrated juice.
                                      94

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              TABLE 2.  ANNUAL COSTS, INCOME, AND R.O.I.
                   ITEM

       Rev. Osmosis module replacement
       Direct labor (10 months, 3 shifts of 5)
       Indirect labor (12 months, 1 shift of 7)
       Potatoes (at $0.75/cwt.)
       Oil ($13.40 per barrel, 75% effic.)
       Electricity ($0.025 per kwhr)
       Maintenance (land and buildings at 2%)
       Maintenance (equipment at 6%)
       Taxes and insurance (3% at fixed costs)
       Depreciation on buildings (4%)
       Depreciation on equipment (10%)
       Interest on working capital
       General plant overhead (50% of maintenance
         and direct labor)

       Total Costs
                                                COST OR INCOME,$

                                                       41800
                                                      184600
                                                      140000
                                                     1500000
                                                      152600
                                                       27700
                                                        7300
                                                      151900
                                                       86900
                                                       13100
                                                      253100
                                                       20000

                                                      171900
                                                     2750900
       Starch ($0.10 per pound)
       Pulp ($100. per ton)
       Protein ($215.  per ton)
       Cone, juice ($78. per ton)
                                                     3044000
                                                      309200
                                                      223600
                                                      335400
 II.
Total Income
3912200
III.
R.O.I.:  40.1%
                                   95

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               TABLE 3.   ESTIMATED FI£ED CAPTIAL INVESTMENT
                         UNDER LIVESTOCK OPTION
                         ITEM                                  COST. $

    I.   Equipment:   Same  as Table 1  less  pulp  drier,  hammer
        mill,  conv.  sys.,  and bins;  less  evaporator;  use  of
        smaller  sizes  of  boiler  and  fuel  tank; but with
        larger cone, juice tank.                                 771700

   II.   Installation (30Z of I.)                                 231500

 III.   Piping,  wiring, and control  systems  (40% of I
        and  II)                                                  401300

   IV.   Engineering  and contractors' fees (20% of
        I, II  and III)                                           280900

   V.   Contingencies  (15% of I,  II, and  III)                    210700

  VI.   Trucks:  Same  as Table 1.                                117000

 VII.   Land                                                     40000

VIII.   Buildings (somewhat  smaller processing area than
        used in  Table  1).                                        296800
   X.  Total Fixed Costs
2349900
                                   96

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                 TABLE 4.  ANNUAL COSTS, INCOME, AND R.O.I.
                           FOR LIVESTOCK OPTION
                      ITEM

     Rev. osmosis module replacement
     Direct labor (10 months, 3 shifts of 5)
     Indirect labor (12 months, 1 shift of 7)
     Potatoes (at $0.75 per cwt.)
     Oil ($13.40 per barrel, 75% effic.)
     Electricity ($0.025 per kwhr)
     Maintenance (land and buildings at 2%)
     Maintenance (equipment at 6%)
     Taxes and insurance (3% of fixed costs)
     Depreciation on buildings (4%)
     Depreciation on equipment (10%)
     Interest on working capital
     General plant overhead (50% of maintenance and
       direct labor)

  I. Total Costs
COST OR INCOME, $

        41800
       184600
       140000
      1500000
        65700
        25800
         6700
       120800
        70500
        11900
       201300
        20000

       156000
      2545100
 II. Total Income:  Same as Table 3 but less income
     from cone, juice
      3576800
III. R.O.I.:  43.9%
                                     97

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 SUMMARY

 It  can be seen from Tables  2  and 4  that  income  from  starch is critical and de-
 partures  from the  assumed $0.10  per pound  (18%  moisture) will have a great effect
 on  R.O.I.   Thus, a company  planning expansion into this area should investigate
 carefully how the  price of  various  unmodified starches will vary in coming years
 as  they can be modified in  several  ways  to meet many of the traditional uses
 of  potato starch.

 The economics discussed in this paper are based on a plant processing  500
 tons of potatoes per day (20 hours) of a 200-day season.   Various  estimates
 have placed cull production as 10% of the crop, i.e.,  somewhat  over  a  million
 tons of cull potatoes annually.   The plant described would thus process  about
 one tenth of the nation's  cull potato production and would appear  to be  the
 largest practicable.  This  is especially true in light of  recent advances in
 potato-based products such as flours and granules which upgrade small  potatoes
 to  food use.

 On  the other hand, the 76  tons of starch produced by the described plant is
 small when compared to corn starch plants in this country  or potato  starch
 plants in Europe.   Reducing the  plant size would reduce the R.O.I, which is
 already borderline (although still acceptable,  especially  for a farmers'
 cooperative) for new plant  development.

                                 REFERENCES
1.  Rosenau, J. R., Whitney, L. F., and Elizondo, R.  Low wastewater potato
    starch/protein production process—concept, status, and outlook.  Pro.
    of the Seventh National Symposium on Food Processing Wastes, Atlanta,
    GA (1976).

2.  Rosenau, J. R., Whitney, L. F., and Haight, J.R.  Potato juice processing.
    Proc. of the Eighth National Symposium on Food Processing Wastes, Seattle,
    WA (1977).

3.  Haight, J. R., Rosenau, J. R., and Whitney, L. F.  Process optimization
    for dewatering coagulated potato juice protein.  ASAE Paper #77-6505
    presented to the Winter Meeting of the American Society of Agricultural
    Engineers, Chicago, IL, December 13-16, 1977.

4.  Rosenau, J. R., Whitney, L. F., and Haight, J. R. Upgrading potato starch
    manufacturing wastes.  Paper accepted for presentation to the annual
    meeting of the Institute of Food Technologists, Dallas, TX, June 4-7, 1978.

5.  Anon.  Economic indicators.  Chemical Engr. 85(2) :7 (1978).

6.  Enochian, R. V., Edwards, R. H., Kuzmicky, D. D., and Kohler, G. 0.  Leaf
    protein concentrate (Pro-Xan) from alfalfa:  an updated economic evaluation
    ASAE Paper No. 77-6538.  Presented to the Winter Meeting of the American
    Society of Agricultural Engineers, Chicago, IL, December 13-16, 1977.

                                      98

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7.  Peters, M. S. and Tiramerhaus, K. D.  Plant Design and Economics for
    Chemical Engineers, 2nd ed.  McGraw-Hill Book Company, New York (1968).

8.  Sohns, V. E.  Cost analyses for new products and processes development
    in USDA laboratories.  J. Am. Oil Chemists' Soc.  48(9):362A (1971).

9.  Vosloh, C. J., Jr., Edwards, R. H., Enochian, R. V., Kuzmicky, D. D.,
    and Kohler, G. 0.  Leaf protein concentrate (Pro-Xan) from alfalfa:
    an economic evaluation.  National Economic Analysis Division, Economic
    Research Service.  Agricultural Economic Report No. 346 (1976).
                                     99

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                     NITROGEN FIXING BIOMASS FOR AEROBIC
              TREATMENT OF SOFT DRINK BOTTLING PLANT WASTEWATER

                                      by

                         P. Y. Yang* and I. S. Ting**


 INTRODUCTION

 In order to achieve satisfactory biological treatment of. wastewater,  the
 wastewater should contain sufficient carbon, nitrogen, phosphorus, and  trace
 minerals to meet the metabolic requirements for cell growth.   For most  food
 processing wastes,  nutritional balance is not a problem since  there usually
 is enough carbon, nitrogen,  phosphorus,  and trace minerals.  However, certain
 food processing wastewaters, such as those from sugar refineries, tapioca
 processing, pineapple canning and processing, and soft drink bottling pro-
 cessing,  have a deficiency of nitrogen which must be added in  proper amounts
 to achieve appropriate biological treatment of these wastewaters.  Modifica-
 tion of  the activated sludge process for the treatment of nitrogen-deficient
 organic wastewaters has been studied (1)  (2) in order to achieve effective
 COD removal,  to reduce the additional cost of nitrogen and to  minimize  the
 nitrogen  concentration in the effluent.

 Azotobacter sp have long been used as non-symbiotic,  free nitrogen fixing
 bacteria  to improve the yield of  a crop  (3).  This  concept has been intro-
 duced for the treatment of nitrogen-deficient synthetic wastewater by using
 Azotobacter Vinelandii (4).   Therefore,  the application of this concept for
 the treatment of  nitrogen-deficient food  processing wastewater and develop-
 ment of necessary design criteria for the operation of this system will
 certainly be  useful for the  reduction of  operational  cost and  achieve the
 necessary effluent  quality.   The  Sermsuk Company, Ltd., Bangkok, Thailand,
 has operated  an activated sludge  treatment plant with an averaged raw waste-
 water flow rate of  52  m3/hr  (13,738 gal/hr)  and  COD of 1150 mg/1 for many
 years.  Handling  of this  soft drink bottling plant  wastewater  has created
 problems  as follows:   addition of inorganic  nitrogen,  bulking  sludge, and
 excess sludge handling.   In  order to improve and modify the existing perform-
 ance of the treatment  plant,  studies were carried out  for several years at
 the Asian Institute of Technology,  Bangkok,  Thailand  (2) (5) (6) (7).  How-
 ever, it  was  felt that further study on  the  reduction  of nitrogen addition
 and excess  sludge production would  also be useful if  such a process could be
 developed.

MATERIALS AND METHODS

Wastewater  collected from the  soft  drink bottling plant of the Sermsuk Com-
pany, Ltd., was used for  the present  study.   In  order  to enrich the growth


 *Department of Agricultural Engineering, University of Hawaii, Honolulu,
  Hawaii  96822
**Malaysia  International Consultants  Co., Kuala  Lumber, Malaysia

                                      100

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medium, other minerals were added as shown in Table 1.  This medium was used
for the development of appropriate nitrogen fixing biomass (NFB) which could
be used for the study of feasibility and kinetic behavior of batch and once-
through continuous cultures.  Apparatus for these two cultures are shown in
Figure 1.  Volume of aeration chamber for batch and continuous cultures is
1.5 and 6.0 liters,respectively.
               TABLE 1.  COMPOSITION OF NITROGEN FREE MEDIUM


          Composition                          Concentration, g/liter

                                                      0.8

                                                      0.2

                 • 7H20                                0.2

                 • 2H^O                                0.1
          FeCl2 • 4H20                                0.003

          NaMo04 • 2H20                                0.001
The acclimatized NFB culture (2 milliliters) was transferred to six of 200
milliliters of soft drink bottling wastewater with mineral medium (nitrogen
free) and different initial pH of 5, 6, 7, 8, 9 and 10.  These cultures were
then aerated for 9, 16, and 30 hours.  Remaining COD and suspended solid
concentrations were measured.

For the comparison of performance of NFB and mixed population (MP) cultures,
batch and continuous flow cultures were operated.  In the batch operation,
two kinds of studies were conducted; one for the comparison of NFB (nitrogen
free) and mixed population with supplement of inorganic nitrogen based on
the performances of pH, TKN, suspended solid and COD concentrations, while
the other is the evaluation of biological kinetic constants for the NFB
system.  For evaluation of the biological kinetic constants, different ini-
tial COD concentrations of soft drink wastewater were prepared as 50, 100,
200, 400, 600, 800, 1000 and 1300 mg/1.  Filtrate COD and suspended solid
concentrations were measured.  For the operation of continuous flow (without
sludge recycle) system, different dilution rates of 1/2, 1/3, 1/4, 1/6, 1/8
and 1/13 hour"1 were operated.  Steady-state COD and suspended solid concen-
trations were measured.

The analyses of concentration of suspended solids, chemical oxygen demand
(COD), and total nitrogen (Kjeldahl) were followed according to "Standard
Methods" (8).
                                    101

-------
              .AERATION CHAMBER
                  (1.5 liter)
                                             DRAIN
                          BATCH CULTURE
  EFFLUEN
•AERATION  CHAMBER
            (6.0 liter)
                                       P.K—PUMP
                                            AIR
                                             WASTEWATER
                      CONTINUOUS CULTURE
FIGURE 1, APPARATUS FOR  NFS  CULTURE
                              102

-------
 RESULTS AND  DISCUSSION

 In  the present  study, the  initial NFB was acclimatized with pH 7.0 with ni-
 trogen-free  soft drink wastewater.  Once the NFB was developed, the deter-
 mination of  optimal range  of pH followed.  The result is shown in Figure 2.
 Apparently,  the optimal range is between 6 to 9.  This also indicates that
 the NFB can  be  more active with high pH than with low pH.

 The general  performance of NFB and MP systems in the batch operation is shown
 in  Figure 3.  It indicates that both systems perform at the same efficiency
 of  COD removal  but differ  in the accumulation of suspended solid concentra-
 tions and TKN contents.  In the NFB system, less accumulation of suspended
 solid concentration and lower TKN content results as compared to the MP sys-
 tem with the same initial  COD concentration.  Apparently, the biological
 kinetic behavior of the NFB system has merit.  As shown in Figures 4, 5 and
 Table 2, the yield value (Y), maximum growth rate (vim) and saturation con-
 stant (Ks) are  different in both systems.  Lower value of cell yield in the
 NFB system would certainly represent an important parameter for excess
 sludge handling as practiced in the conventional activated sludge process.
 In  addition, the lower value of TKN in the effluent of the NFB system is
 very important  since higher content of nitrogen concentration in the effluent
 will cause an eutrophication problem in the receiving stream.
            TABLE 2.  COMPARISON OF BIOLOGICAL KINETIC CONSTANT


        Biological
     Kinetic Constants          NFB System               MP System  (9)

       ym, hour"1                    0.30                     0.62

       Kg, mg/liter                260                      125

       Y, mg/mg                      0.137                    0.53
In order to observe the operational characteristic of continuous flow opera-
tion, these two systems were operated as once-through continuous completely-
mixed flow with different dilution rates.  The results are shown in Figures
6 and 7.  According to the dilute-out curve shown in Figure 6, the NFB sys-
tem shows no wash-out of suspended solid even when 0.5 hour"1 of dilution
rate is provided.  This does mean that the volume of the secondary settling
chamber can be drastically reduced for handling of the secondary sludge pro-
duced from the aeration chamber.  Furthermore, the effect of dilution rate
on the cell yield values and COD removal efficiency for these two systems
are shown in Figure 7.  It can be seen that the NFB system provides nearly
the same COD removal efficiency with the MP system with much lower cell
yield values at different dilution rates as compared to the MP system.  Ap-
parently the NFB system utilizes a greater portion of the substrate as an
energy source for the nitrogen fixation process rather than synthesis of

                                    103

-------
V)
Q
Lu
CL-
IO

CO
     300
    200
100
            56789

               INITIAL pH VALUES
INCUBATION TIME



  o     30 hrs

  a     |6 hrs

  ?      9 hrs
        FIGURE  2, OPTIMAL  pH DETERMINATION
                             104

-------
X
a.
      9.0
      8.0
      7.0
Q

O
tt
CO
Z3
CO
\   400




    300




    200




     100




       0




      75




      50




      25




       0
 \
\
o»
                                   Seeded  with  NFB


                                  Seeded with Mixed  population and

                                  •upplemenlated  (NH,XS04 at ratio of

                                  N/COD* 1/20
              6     12    IS   24      ^   50


                INCUBATION   TIME, hrs.


     FIGURE  3,COMPARISON  OF  NFB AND  MP CULTURES



                               105

-------
          s

         cO
         2   150
          Q
          uJ
          Q
             fOO
              50
          ID
          C/D
                                    Y--0.1375
               0     200  400   50O  800   1000  I2OO

                        COO UTIUZED  mc^,


    FIGURE 4  j   YIELD COEFF(CENT CURVE  IN  BATCH CULTURE
o
o


UJ
   UJ
Or
cr
H
cO
03
Z>
CO
O
o:
  o

  d

  o
  LU
  CL
  CO
                200   40O  6OO   800  lOOO  1200  I4OO



                ^INITIAL SUBSTRATE CONCENTRATION;mg/(


    FIGURE 5, DETERMINATION  OF MAX. SPECFIC GROWTH RATE ty*

              AND  SATURATION CONSTANT  K  IN BATCH CULTURE
                            106

-------
      cr«
      c/)
      c/5
1000




800




600




400




200
                     EFF. COD (NFS)


                     EFF.GOD (MP)

                     MLSS (MP)


                     MLSS (NFB)
            0    0.1    0.2    03   04

                     DILUTION RATE hr~*
         FIGURE 6; DILUTION CURVE  FOR  NFB  AND  MP  SYSTEMS.
       "„  K)0

       >-
       o

       |  80
       O
       u_
       u_

       ^  60
          40
       LU

       OL
       o   20
       o
       o
            0
         01
0.2   03   04   05
                     100




                     80




                     60




                     40




                     20




                     0
                                                g


                                                LJ
                                                 LU

                                                 O
                     DILUTION RATE  hr
                                      ~'
FIGURE  ^    EFFECT  OF DILUTION RATE  ON  COD REMOVAL  AND


            YIELD VALUE
                               107

-------
 biomass  as the MP system does.   According  to  the present  study, it is shown
 that  the NFB system can be  operated  as  the MP system except for nitrogen
 addition.

 The present study provides  a potential  which  can be explored for further
 study on the operation  of sludge recycle continuous flow  systems which can
 be more  practical in actual operation.

 SUMMARY

 It is technically and economically feasible to treat the  nitrogen-deficient
 carbohydrate wastewater by  the NFB system  with effective  COD removal, low
 sludge production and low nitrogen content in the effluent.  Biological
 design constants  including  maximum specific growth rate of biomass, satura-
 tion  constant and cell  yield value are  different for the  NFB and MP systems.
 Further  study should be conducted with  the NFB system on  the biological
 kinetic  behavior  of  sludge  recycle continuous flow completely-mixed system.

 ACKNOWLEDGEMENT

 This work was supported by  scholarships donated by the Lee Foundation, Singa-
 pore,  through the Asian Institute of Technology, Bangkok, Thailand.  Also,
 this  paper  was approved by  the Director of the Hawaii Agricultural Experiment
 Station.
                                 REFERENCES
1.  Komolrit, K., Goel, K. C., and Gaudy, A. F. Jr., Regulation of exogenous
    nitrogen supply and its possible application to the activated sludge
    process.  J. Water Pollution Control Federation 39:251 (1967).

2.  Yang, P. Y., and Chan, L. K.  Modified activated sludge process for treat-
    ment of nitrogen-deficient organic wastes.  J. Water Pollution Control
    Federation 48:1992 (1976).

3.  Goldschmidt, M. C., and Wyss, 0.  Chelation effects on Azotobacter cells
    and cysts.  J. of Bacteriology 91:120 (1966).

4.  Finn, R. K., and Tannahill, A. L.  The azotopure process for treating
    nitrogen-deficient aqueous wastes.  Presented at 164th National Meeting
    of American Chemical Society, N. Y., August, 1972.

5.  Tsui, T. S.  Soft drink bottling plant wastes handling study.  M. S.
    Thesis No. 640, Asian Institute of Technology, Bangkok, Thailand (1975).

6.  Yang, P. Y., and Chen, Y. K.  Operational characteristics and biological
    kinetic constants of extended aeration process.  J. Water Pollution
    Control Federation 49:678 (1977).
                                     108

-------
7.  Yang, P. Y.  Biological kinetic behaviours and operational performances
    in the aerated and oxygenated systems.  Biotechnology and Bioengineering
    19:1171 (1977).

8.  Standard Method for the Examination of Water and Wastewater.  13th Ed.,
    American Pub. Health Assn., New York (1971).

9.  Yang, P. Y., Hsu, C. H., and Thijayung, C.  Biological kinetic behaviour
    of completely mixed air and pure oxygen systems.  Proceeding.  IFAC on
    Environmental Systems Planning, Design and Control, Pergamon Press.
    p. 723 (1977).
                                   109

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             TREATING TROUT PROCESSING WASTEWATER -
                   A SUCCESSFUL CASE HISTORY
                     John  S. Keith, P.E.*

 INTRODUCTION

 The Thousand Springs Trout Farms, a subsidiary Pf
 Corporation, is a producer of fresh and frozen rainbow trout
 for the restaurant market.  It is located in the beautiful Snake
 River Canyon, outside Buhl, Idaho.  In this paper, the wastewater
 problems of Thousand Springs trout processing plant will be
 discussed, and the efforts made to clean up the wastewater will
 be reviewed.

 Historically, the wastewater from Thousand Springs' processing
 plant was never considered a pollution problem.  First of all,
 the amount of wastewater involved - around 70 gallons per minute -
 was insignificant when compared to the water discharged by the
 adjacent trout farm — some 45iOOO gallons per minute.  And second,
 the contaminants in the wastewater were considered as generally
 good for the receiving waters - an opinion supported by the
 large population and record size of trout in Clear Lake, the
 receiving water for Thousand Springs.  Consequently, the only
 wastewater treatment done  was coarse screening.  However, in
 order to comply with the strict limits of Thousand Springs'
 NPDES permit, it was clear that a major clean-up program would
 be necessary.  A two stage program was planned i first, reducing
 the amount of pollution coming from the plant by improving water
 use practices; and second, installing an effective end-of-pipe
 treatment system.

 IN-PLANT CLEAN-UP

 The first step of any water pollution control project is to
 define the problem.  This  was done by carefully inspecting the
processing plant, identifying specific wastewater source opera-
 tions, and conducting a sampling program.  To insure the validity
 of data obtained, great care was taken when conducting the
 initial wastewater sampling, and all subsequent sampling! com-
posite samples,  encompassing all production activities, were
 taken for several days.  Where possible, the results were
 correlated with historical data.

Upon evaluation,  it was found that four operations were respons-
 ible for virtually all of  the processing plant wastewater.


*Inmont Corporation,  Corporate , Engineering Department
 Hawthorne, New Jersey

                               110

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These operations werei evisceration of the trout by automatic
"gutting machines"; manual rinsing and cleaning of eviscerated
trout at "rinse tanks"', manual boning of the cleaned fish at long
"boning tables"', and washing down of the processing equipment and
work areas at breaks and the end of shifts.  Wastewater from this
last operation was commonly called "floorwater", after the worker's
custom of allowing wash water hoses to run continuously on the
plant floor.  Other operations at the plant —chilling, inspection,
weighing, packing and freezing — were found to involve little or
no wastewater.

The results from the initial sampling program are given in
Table I.  In general, the plant effluent was found to be quite
foul.  It had a color varying from light to dark pink, a high
degree of turbidity, a definite fishy odor, and a somewhat greasy
feel.

As can be seen from the table, the gutting machines were by far
the most significant source of pollution in the plant, contri-
buting about 36jf of the total flow and over 90jf of the contami-
nation.  This result was not surprising; it is at the eviscer-
ating machines that the fish are first opened up, and the
"pollutants" - blood, body fluids, and solids - first allowed
to mix with water.  Compared to the gutting operation, rinsing
and boning were not significant sources of contamination, although
the boning tables did contribute an unexpectedly high portion of
the total wastewater flow.  No practical way was found to sample
floorwater.  However, based on appearance, the floorwater did
not appear to get worse than the average plant effluent, and
was usually much cleaner.

The next step in the clean-up program was to determine how the
water use practices at each source could be improved.  Since it
was already clear due to the strictness of the NPDES permit that
end-of-pipe treatment would be necessary, methods for reducing
both the degree of contamination and the quantity of wastewater
were investigated, so that the treatment system would be as small
as possible.

By inspection, it was clear that the "floorwater" could be easily
reduced.  There was no apparent reason why wash hoses had to be
left on at all times, so plant personnel were instructed to turn
off the hoses when not in use.

After considerable review with the plant supervisors, it was
decided that water use at the boning tables could be eliminated
almost entirely.  Basically, the boning water was used only as
a means for conveying bones away from the worker's stations.
To eliminate this water conveying system, plastic buckets were
placed next to each worker's station.  The bones are now directed
into buckets by chutes, and are carried away by a designated
employee.  While more labor is involved, a very considerable

                               111

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         TABLE I - INITIAL WASTEWATER CONDITIONS
Parameter
Flow (gpm)
BOD5 (mg/1)
TSS (mg/1)
Oil tt Grease (mg/1)
Plant
Effluent
67-3
502
295
690
Gutting
Machines
24.4
1820
3186
1722
Rinsing
Tanks
11.9
190
94
168
Boning
Tables
23.8
115
22
4
  Notes  Floorwater could not be isolated for sampling
         TABLE II - RESULTS OF CLEAN-UP PROGRAM
                                            Reduc-   Reduc-
                        Effluent  Effluent  tions    tions
              Effluent  After     After     After    After
                        Modifi-   Treat-
Parameter
Before
Clean-up  cations   ment
Modifi-  Treat-
cations  ment
Avg. Flow (gpm)
Max. Flow (gpm)
BOD*
(lb/1000 Ib Fish)
TSS
(lb/1000 Ib Fish)
Oil & Grease
(lb/1000 Ib Fish)
67-3
75
19.8
11.6
27.2
29-3
30
14.0
6.6
2.3
25.3
30
2.3
1.2
0.4
62. 4*
60*
29-3*
43-1*
91-5*
                                                       60*
                                                     89.7*
                            112

-------
reduction of wastewater was achieved, and surprisingly, the
Zoning area is a bit cleaner (the water conveying system was
prone to frequent plugging).

At the rinse tanks, the trout are checked to see if the
gutting machines have cleaned out all the viscera.  The fish
are rinsed and any remaining viscera is manually removed.  Only
a slight reduction in water use was achieved at this source.
However, a fair amount of contamination was prevented by having
the removed viscera placed into a trough leading to a bucket,
rather than thrown into the rinse tanks.

Because the gutting machines were the major water pollution
source in the processing plant, more effort was spent on
cleaning up them than the other sources.  By reducing water
flow rates at the various sprays and nozzles in the machines,
water consumption was cut about in half.  However, this did
not significantly affect the amount of contamination.  To
reduce contamination, a scheme for removing viscera from the
wastewater right at the machines was tried.  This idea was
based on information in the literature indicating that the
longer fish viscera is allowed to remain immersed in water, the
more contaminants leach out into the water (1).  To test the
idea, a makeshift separation system was installed.  Test samples
showed very promising results — a 33^ reduction in BOD and a
59# reduction in oil and grease.  With the importance of the
leaching phenomenon confirmed, attempts were made to install a
permanent separation system right at the gutting machines.
While such a system was eventually completed, it proved to be
rather cumbersome, labor intensive, and prone to breakdowns.

Fortunately, while the viscera separation system was being
worked on, the management at Thousand Springs was also investi-
gating more modern gutting machines — machines that employed a
vacuum for removal of viscera, rather than mechanical removal
and water disposal.  The new machines were being considered
primarily for production reasons, but the managers were
confident that they would help with the wastewater problem.
The machines were purchased and installed in the summer of
1977, and have proved to be significantly less polluting than
the old machines.  This is because with vacuum removal, the
viscera and much of the blood is sucked away and does not mix
with any water.  Water consumption by the new machines is also
less than by the old machines.

Some mention should be made about the method of disposing of
the fish viscera, bones, etc. from the processing plant.  The
wastes are picked up daily and hauled away as animal feed for
mink — who apparently love it.  When significant changes in the
waste handling methods were made, the effects of these changes
on the mink farmers was considered.  Generally, the owners of
the mink farms were accommodating to Thousand Springs' needs.

                               113

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 In some ways they even came out ahead as a result  of  the  changes.

 After all the water use changes and modifications  in  the  pro-
 cessing plant were completed,  samples of the  plant effluent were
 again taken.   Table II gives the results of these  tests,  along
 with the initial  test results,  and the results  of  tests done
 after installation of the  treatment system.   As Table II  shows,
 the in-plant changes resulted in considerable reductions  in
 wastewater flow rates and  in overall contamination.   In view of
 these reductions,  the -first stage of the clean-up  program was
 judged to be successful.

 It should be noted that the results concerning  BOD, TSS,  and
 oil and grease are given in terms of pounds of  contaminant per
 thousand pounds of fish processed.   Since production  at the
 processing plant  has more  than doubled since  the wastewater
 clean-up program  began —  to a current production  peak of over
 30,000 lbs/day>-such a production-based measure is necessary
 to allow meaningful comparisons.

 TREATMENT SYSTEM  INSTALLATION

 After the various  changes  in the processing plant  were in place
 (except for the new gutting machines,  which weren't installed
 until later) ,  an  investigation was made into  what  type of treat-
 ment  system to install.  Performance criteria for  a treatment
 system were based  on what  was needed to achieve compliance with
 the final limits  of Thousand Springs'  NPDES permit.

 When  evaluating wastewater treatment strategies, the  problem of
 space was very important.   The  Thousand Springs Trout Farm is
 very  short on space,  and any large treatment  system would have
 cut into  productive fish impoundments.   The only readily  avail-
 able  space was a little-used building at the  outfall  end  of the
 trout  farm, measuring about  16  feet wide,  30  feet  long, and 9 to
    feet high.
Several treatment strategies were investigated, including lagooning,
extended aeration, activated sludge treatment, chemical treatment
and air flotation.  Lagoons and extended aeration systems were
ruled out because of space requirements.  Chemical treatment
was eliminated because of generally low treat ement efficiencies
and lack of data relating to fish processing wastewater.
Activated sludge systems were found to be feasible » however,
such systems still required somewhat more space than was readily
available.  Also, they would cost more than twice as much as air
flotation systems, and would have trouble with the high oil and
grease loadings.

The literature indicated that air flotation systems, with chemi-
cal additions, could treat fish processing wastewater as effec*


                                114

-------
tively as conventional "biological treatment systems, and yet
take up very little space (1) (2).  A number of flotation
system manufacturers were contacted and invited to submit pro-
posals based on the performance criteria.  Both dissolved-air
and dispersed-air flotation systems were considered.  The
system selected was a dispersed-air flotation system with
chemical addition and fine screening, proposed by SWECO, Inc.^.
SWECO was selected primarily because they appeared to have tKe
most experience with fish processing wastes and because they
could guarantee the greatest BOD removals.

Wastewater treatment in the SWECO system is done primarily by
three pieces of equipment — a coarse belt screen, a centrifugal
screen concentrator (CSC), and a sludge flotation tank.  The
belt screen consists of a series of polyethylene panels with
l/^K-inch openings.  The CSC is essentially a rapidly rotating
drum with screens on the outside, through which the wastewater
is pumped from the inside.  It uses 165-mesh stainless steel
screens.  The flotation tank measures & feet wide, 12 feet long,
and ^ feet deep, and is equipped with a foam skimmer.

Other components of the SWECO system are a 300-gallon surge tank,
a non-clog wastewater pump, a vibrating separator with 165-mesh
screens, three chemical feed tanks and pumps, an automatic
screen washing system, a 1500-gallon sludge holding tank, and
an integrated control panel.  The system operation is described
below.

Wastewater from the processing plant flows by gravity to the
SWECO room.  Once there, it falls through the coarse belt
screen into the surge tank.  Large pieces of fish viscera are
removed by the belt screen, and are dumped into a chute leading
to the sludge holding tank.  The surge tank serves to level out
peaks in the wastewater flow rate.  Alum is added to the waste-
water at the surge tank.

From the surge tank, the wastewater is pumped to the centri-
fugal screen concentrator, with lime being injected into the
stream right after the pump.  The CSC serves two functions!
it removes fine solids, and it aerates the wastewater.  Solids
removed by the CSC flow out the bottom of the unit to the vibra-
ting separation screen, which dewaters them.  The dewatered
solids are discharged to a drum, while the water is recirculated
back to the surge tank.  Just prior to leaving the CSC unit, an
anionic polymer is injected into the wastewater stream.

The wastewater then flows by gravity to the bottom of the
flotation tank.  There, the fine floe formed due to the alum
and lime addition is coalesced by the polymer and floated to
the top of the flotation tank by entrained air.  A moving
skimmer pushes the floating, foamy sludge over a collection weir


                               115

-------
 into a trough,  from which it flows to the sludge holding tank.
 After skimming,  the fully treated wastewater is discharged
 over another weir.   Sludge and solids collected in the holding
 tank are periodically pumped out and hauled away to a landfill.

 The entire treatment system is controlled from one control panel,
 and can be operated either manually or automatically.   Periodically,
 the system cycles into a cleaning mode.   In this mode,  the fine
 screens of the  CSC  unit and vibrating separator are backwashed
 by a high pressure  spray of hot water mixed with detergent.

 With regard to  space,  the SWECO treatment system fits quite
 comfortably into the l6-by~30 foot room available,  with ample
 room left over  for  a workbench and storage shelves.   The sludge
 holding tank is  located underground outside the room.

 As with most complex installations, the start-up of the SWECO
 treatment system had a few problems.   In particular,  problems
 were encountered with the wastewater pump due to stringy solids,
 and with the coarse screening operation (not part of SWECO's
 package).   But  for  the most part,  these problems have  now been
 overcome.   Initial  chemical concentrations were as suggested by
 Barnett and Nelson  in their studies - 220 mg/1 of alum,  150 mg/1
 of lime and 5 mg/1  of polymer (2).

 The results of  tests to determine the efficiency of the SWECO
 system  are shown in Table III belowi

             TABLE III  - PERFORMANCE OP SWECO SYSTEM
                           Raw          Treated     Treatment
Parameter
BOD5 (mg/1)
TSS (mg/1)
Oil and Grease
Wastewater
1180
562
(mg/1) 189
Wastewater
189
100
28
Efficiency
8W
82*
85*
The tests show that the system is quite efficient in treating the
wastewater.  It should be noted that when the tests were made, no
effort had yet been made to optimize removals by adjusting chemi-
cal feed rates, cleaning frequency, etc.  After some experience,
removal efficiencies are expected to be even better.

CONCLUSIONS

Referring again to Table II, it can be seen that, overall, the
wastewater clean-up program at the Thousand Springs Trout Farm

                                116

-------
was very successful.  Reductions of BOD and suspended solids
were close to 90#, and the reduction of oil and crease was a
remarkable 98.5#-  As experience is gained with the SWECO
treatment system, better reductions may be achieved.

Considering the reductions obtained, it is felt that the cost
of the clean-up program was very reasonable.  Installed cost
of the SWECO treatment system was about $60,000 (197? dollars),
while the cost of the entire clean-up program was about $80,000.
These cost figures include all testing and engineering, but
do not include the cost of the new gutting machines, which were
installed primarily for production reasons.  The cost figures
also do not include the labor of Thousand Springs Trout Farm
personnel, who contributed nearly all of the labor involved in
the project.
                          REFERENCES

1.  Environmental Associates, Inc.  Upgrading Seafood
    Processing Facilities to Reduce Pollution.  Environ-
    mental Protection Agency Technology Transfer
    Program (197*0 •

2.  Barnett, Harold J., and Nelson, Richard W.  A Preliminary
    Report on Studies to Develop Alternative Methods of
    Removing Pollutants from Tuna (Albacore) Process
    Wastewaters.  Unpublished.
                        ACKNOWLEDGMENT

The author would like to express his sincere appreciation to
Messrs. S. Davis, M. Fennen, and R. Eggleston of the Thousand
Springs Trout Farm for their untiring work towards the success
of this project.
                              117

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            RECIRCULATIOlN OF CONTAINER COOLING WATER
                 ASA MEANS OF WATER CONSERVATION
                     IN FOOD PROCESSING PLANTS

                                    by

                             Nabeel L. Jacob*


INTRODUCTION

Water is the most common medium used for cooling thermally processed
containers of food.  Cooling is accomplished in a variety of systems such as
the use of still retorts as coolers, cooling canals, agitating spin coolers,
rotary pressure or atmospheric coolers,  spray coolers or water application
in the cooling leg of a hydrostat ( 3 ).  In general,  cooling water is either used
once and discharged or reused for cooling, or other purposes.

Container cooling is one of the most water consumptive operations in any food
processing plant.  Depending on the type of product packed and the water use
practices,  cooling water requirements represent between 25 to 85 percent of
the total volume of water used daily in the plant ( 1 , 3 ). Acquisition of such
a large volume  of water is no longer free even for the processors who rely
exclusively on wells for their fresh water supply.  Disposal of wastewater,
whether to a municipal treatment plant or to a company operated treatment
facility, has also become a significant cost item in food processing.  There-
fore,  maximizing the use of such a copious volume of good quality cooling
water, through  recirculation or reuse, can be an effective means of im-
plementing a successful, overall water conservation program through which
substantial savings can be  realized ( 3 ).

NFPA SURVEY  OF CONTAINER COOLING SYSTEMS

Recognizing the significance of the microbiological,  chemical and physical
characteristics  of cooling water as major factors determining the feasibility
and extent of its reuse, a survey was conducted by NFPA (formerly NCA) to
specifically determine these characteristics in a number of container cooling
systems.

Over the two-year period of the project,  a total of sixty-five (65) visits were
made to seventeen (17) California canneries where 210 cooling water samples
*National Food Processors Association, Western Research Laboratory,
 Berkeley, California.
                                    118

-------
were collected for laboratory testing.  The study covered seven (7) different
cooling systems,  eight (8) major commodities and twelve (12) specialty prod-
ucts.

In general,  samples were collected in various ways depending upon the type
of cooling system surveyed.  At the time of sampling, the concentration of
total residual halogen (chlorine or iodine) in the water was determined and
the temperature and pH were recorded.  Residual chlorine or iodine  in water
samples collected for microbiological testing was immediately neutralized by
adding sterile 1% sodium thiosulfate solution.  Samples were then refrigera-
ted, for no longer than 40 hours, until examined.  All laboratory  tests were
performed in accordance with the Standard Methods for the Examination of
Water and Wastewater ( 5 ).

RESULTS AND DISCUSSION

The physical and chemical  characteristics of the samples collected are sum-
marized in Table  I.   The total hardness (as CaCO3) showed the highest de-
gree of dispersion as  determined by the standard deviation value. The least
variability was that of the pH of the water.  The TOG/COD  ratio had  a range
of 0. 10-4.41 with an  arithmetic mean of 0. 63 and SD  of 0. 69.  Halogen con-
centration will be considered in a later part of the  discussion.
 TABLE I.  SUMMARY OF CHEMICAL AND PHYSICAL CHARACTERISTICS
Characteristic
COD, ppm
TOC, ppm
TSS, ppm
Hardness (CaCO3), ppm
Grease & Oil, ppm
Temperature, °C
pH
Range
0. 0
0.0
0.0
10.0
0. 0
9.4
6.0
- 281.0
- 77.0
- 98.0
- 500. 0
- 23.0
- 66.7
- 9.6
Mean
26.9
12. 8
4.4
92.7
4.0
28. 1
8. 1
S.D.
37.8
11.5
6.3
87.8
4.2
19.5
0.53
Microbiologically,  the aerobic Total Plate Count (TPC), aerobic and anaer-
obic Mesophilic Spore (MSC), Staphylococci and Coliform  Counts were deter-
mined in the cooling water samples.  Table II gives a  summary of these
characteristics.

                                    119

-------
    TABLE II.  SUMMARY OF MICROBIOLOGICAL CHARACTERISTICS

          Characteristic                     Count/ml  (Range)
          Total Plate Count (TPC)              <1 - 205,000*
          Mesophilic Spore Count (MSC)
                a. Aerobic                     < 1 -  20
                b. Anaerobic                   < 1 -   4
          Staphylococci                        <1 -  13

          Coliforms                           <1 - 950*


*No detectable germicide residue.

An examination of the percentage distribution of bacterial counts in the
samples (Table III) indicates that 64% of the water  samples had TPC in the
range of < 1 - 100/ml.  Of these samples, 40% showed negative results
(< I/ml).  The MSC was generally low.  There were no detectable aerobic
sporeformers in about  80% of  the samples,  and the maximum count did not
exceed 20/ml.  Anaerobic sporeformers were only recovered from 4% of the
samples and at low density levels (highest count was 4/ml).  Staphylococci
counts of between 1 and 10/ml were present in only 3% of the samples.
Densities of more than 10/ml (with a maximum of 13/ml) were encountered
in 1% of the water samples.  Toxin tests were negative in all samples that
showed positive Staph results.  Coliforms were detected in about  12% of the
samples.


    TABLE III.  PERCENTAGE DISTRIBUTION OF BACTERIAL  COUNTS
                 IN COOLING  WATER
MSC
Counfc/rnl
<1
1 - 10
11 - 100
101 - 1,000
1,001 - 10,000
10,001 - 100, 000
> 100, 000
TPC
25.6
19.5
19.0
16.4
9.7
6.7
3. 1
Aerob.
79.5
17.9
2.6
-
-
-
_
Anaerob. Staph.
96.4 96.4
3.6 2.7
0.9
-
-
-
_ _
Coliforms
88.2
0.9
1.8
9.1
-
-

                                    120

-------
Occurrences of aerobic sporeformers in relation to different ranges of TPC
had no definite trend.  The anaerobes, on the other hand,  showed a steady
increase with the TPC in ranges higher than 100/ml.

The frequency of coliform and staphylococci detection increased as the
general  bacterial population increased to maximum levels.  However, no
linear trend was apparent.

MAXIMIZING THE USE OF CONTAINER COOLING WATER

Because of the recent drought conditions that affected the western and mid-
western states, food processors should make every effort to maximize the
use of container cooling water.   This can be basically accomplished through
reuse.  The results obtained and observations made in our study indicate
that the voluminous discharge (Table IV) from container coolers is,  in most
cases, more than suitable for reuse, with minimal treatment,  in lieu  of
fresh water.

    TABLE IV.   VOLUME OF WATER DISCHARGED FROM VARIOUS
                  TYPES  OF COOLERS

       Type                 	Range	

       Still Retorts           1300 - 4000 Gal./Cooling Cycle

       Spray Coolers         6300 - 20,000 Gal./Hr.

       Spin Coolers          3700 - 6300 Gal./Hr.

       Cont.  Coolers         2400 - 6000 Gal./Hr.


The reuse of cooling water can be implemented in two ways with the option of
employing both,  or either one exclusively (Fig. I):

                         REUSE OF COOLING WATER
            For Container Cooling                    For Purposes Other
              "Recirculation"                          than Cooling

                                                • Fluming
                                                - Product Washing
         Over a Cooling    Within the
            Tower         Cooler                 • Plant Clean-Up
                                                • Incidental
         • All Types       • Spin Coolers
                        • Spray Coolers


              Fig. I. Water conservation through reuse of cooling water.

                                    121

-------
 1. The reuse for purposes  other than container cooling;
   The discharge from cooling systems can be reused without further
   treatment for fluming and product washing ( 1, 3, 4)   thus eliminat-
   ing a number of points of fresh wateruse.  This practice is known
   as the counter-flow reuse pattern which can be adapted in various
   ways in most food processing plants.  Water conservation acquired
   through this  practice is  depicted in Fig. II which illustrates three unit
   operations common in all food processing plants.
SINGLE USE

50 Gpm 	 •> [ FLUME ] — *• 50 Gpm

50 Gpm 	 + WASHER | — * 50 Gpm

CAN
50 Gpm 	 *• — *• 50 Gpm
V COOLER H
I 150 Gpm
REUSE
[-»- FLUV
1 	
10 Gpm — ^+\ WAS

CAN
50 Gpm 	 *•
v COO

IE ) — *• 60 Gpm

HER *,

J
IR
I 60 Gpm
           Fig. II.  Counter-Flow reuse of cooling water.
   Discharge from coolers can be used also for plant clean-up,  belt lub-
   rication and boilers { 1 ).

2.  The reuse for container cooling purposes;
   This method can be implemented through either, or both, of two ways;
   (a)  Recirculation of the water within the cooler.  This can be readily
       accomplished in spray and spin coolers.  In spray coolers (Fig.
       Ill),  fresh water consumption is significantly reduced by collect-
       ing the water under the final section of the  cooler and reuse it in
       the preceding section and so on.  Water collected under the initial
       section can then be discharged, reused for other purposes or re-
       circulated over a cooling tower and reused for cooling.   The same
       concept applies to spin coolers as illustrated in  Fig  IV.
                                  122

-------
     HOT
     WATER
     o
   PRODUCT
        IN
t-o
CO







/Vl9oPF./\ /\
STERILIZING COOLING
— •* n. n


i.~_~ HOT- rrr~jr JT 'HOT'-"^-
Lirdj"



— |
1


•' \ •' x\
COOLING




 COLD
 WATER
o
                                                                  COOLING        COOLING
                         COMBINED EFF.
                                       TROUGH
                        Fig.  III.  Water recirculation within the cooler "spray cooler. "

-------
                                                                          PRODUCT
                                                                           IN
"^^\
^*^s



-- - -_ - --*! -L- ~~ - - --

J^^~\:
-N:1^
-V-

t
x^^-

^/r~_~_~ — 	
- — — — — — — _ __



K






.*
\
1
':]



V.
\\

                PUMP
                                          TO SUMP
Fig. IV.  Water recirculation within the cooler-"spin cooler. "

-------
      (b)  Recirculation of the discharge from coolers  over a cooling tower
          and reuse for container cooling.  This practice,  as  illustrated in
          Fig.  V, may require some revision of the existing hydraulic flow
          in the plant. However, reductions  of as high as  80% of the daily
          cooling water consumption have been reported  by plants now
          using cooling tower systems.
CANS IN
r
I COOKE


^
1
TO SA
TOWEF

R
— Q-
COOLER n|
D
T
....... TANK fll IT
-S'SSJ ^HIMj UUI
:SUMPJ
L
NITIZE
\
& CHLO
i

RINE
I
r

L.LJ.J



: COOLING.;:
E TOWER =

2 i.~L~L~_r.
PSUMP^
/s's' / S^S

WATER
MAKE-UP
-< 	 J
	 >•
                                        RETURN TO TOWER
               Fig.  V.  Schematic of a cooling tower system.
It should be emphasized at this point that water used in recirculated systems
is particularly prone to bacterial and organic matter build-up as  shown by
the survey data.  Table V shows the effect of recirculation on various charac-
teristics of cooling water.  The build-up trend is apparent.  Therefore,  the
operation of recirculated cooling water systems requires special attention to
avoid adverse conditions.
                                    125

-------
          TABLE V.  THE EFFECT OF RECIRCULATION ON THE
                      CHARACTERISTICS OF COOLING WATER
Characteristic
COD, ppm
TOC, ppm
pH
Residual, C12, ppm
Bacterial Counts/ml:
TPC
MSC (Aerobic)
" (Anaerobic)
Staph.
Coliforms
Single - Pass
(28% of Samples)
0.0 - 133.0
0.6 - 48.5
7.6 - 9.6
0.0 - 9.5

<1 - 1680
<1 - 2
<1
<1 - 1
10.0

<1 - 205,000*
<1 - 20
<1 - 4
<1 - 13
<1 - 950*
*Cooling water contained no detectable germicide residue.
MEANS TO ACHIEVE MAXIMUM USAGE OF COOLING WATER

Based upon the findings and upon the observations made throughout the study,
the following considerations are offered collectively as necessary means of
maximizing the use of cooling -water:

   1. Adequate Knowledge of  the System;
      This is the first requirement in any water conservation program.  Seri-
      ous problems may result  from the lack of knowledge of what I call "the
      system plumbing. "  Misapplication of chlorine, in recirculated water
      systems, is an example.  Therefore,  you should survey the system
      and maintain an updated floor plan or a schematic diagram with  all
      water lines,  points of chlorine application,  sumps  -- etc., indicated
      thereon.  An example of such a map is shown in Figure VI.  This map
      is specifically useful in trouble-shooting.

   2. Disinfection:
      Disinfection is probably the most effective means for achieving maxi-
      mum usage of cooling water.  Our study has shown that the presence
      and level of a germicide residual in the cooling water determine to

                                   126

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       -6-   GftTE



            FIOAT VALVE
NJ
        IW- PLANT


         USfS
                     SUMP
                           COOLIN&

                           TOWER
—I	—&-a-

            9x


     QQQ
  	          X
                                                                         I	•
                                                               C-lt        1

                                                               Y   HOLD T/SMK




                                                               *-4

                                                                     N '
                                                               -n_n	1
                                                                             CHLOR.\^4ATBD


                                                                                 JP H^O





                                                                                 -f-1
                                         Fig. VI.

-------
a large extent the microbiological quality of the water which in turn
determines the feasibility of its  reuse.  Table VI shows the definite
effect of the concentration of residual chlorine on the microbiological
quality  of cooling water.  As  expected,  the results indicate a general
trend towards lower counts of all four groups of microorganisms with
increasing residual chlorine level. In general,  all bacterial counts
were highest when the level was undetectable or low (0. 0-1.0 ppm).
No bacterial growth was encountered, however, at concentrations
higher than 3, 1 ppm.

Selection of the proper germicide should be based upon careful con-
sideration of the  following aspects:
(a)  Thorough evaluation of the germicidal efficacy acquired under
     typical operational conditions.
(b)  The corrosivity of the germicide and the effect of its use on the
     characteristics of the water.
(c)  The regulatory status of the germicide.
(d)  The compatabtlity of the  germicide with other chemicals added to
     the cooling water (e.g.,  oxygen scavengers).
(e)  The cost and added  benefits.

For  several well known  reasons, gaseous chlorine is still the prefer-
red choice of most food  processors. However,  chlorination of con-
tainer cooling water definitely requires adequate control of the resi-
dual chlorine levels in the water.  Inadequate control results in either
corrosion of containers  and equipment or high bacterial counts and
the absence of sanitary conditions in the water.

It  is evident that  the stability and germicidal efficiency of a given con-
centration of chlorine are greatly influenced by the pH,  temperature,
total suspended solids (TSS) and organic load of the water.  Therefore,
the characteristics of cooling water will determine, to a large extent,
the required minimum level of chlorine.  By considering the hardness
of the water, corrosivity can also be predicted ( 3 )•

To achieve adequate control of the established level of residual chlorine,
the plant must have an individual assigned to monitor and maintain re-
cords of residual chlorine concentrations in the cooling  water on a
continuous basis.  Monitoring program should include both water feed-
ing,  and water discharged from,  the cooler.  Monitoring of  residual
chlorine in the latter assures the adequacy of chlorine dosage applied
to the first.
                                  128

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          TABLE VI.  THE EFFECT OF RESIDUAL CHLORINE CONCENTRATION

                      ON BACTERIAL COUNTS* IN CONTAINER COOLING WATER
to
VO
Resid. C12
Rangej ppm
0. 0 - 1. 0
1.
2.
3.
4.

1-2.0
1-3.0
1-4.0
1 - 10. 0
>10. 0
%
MSC
of Samples TPC Aerobic Anaerobic Staph. Coliforms
52.9
14.4
12.3
5.4
13.4
1.6
<1 - 205,000 
-------
   Monitoring and control can be done either manually or automatically.
   Orthotolidine comparators, or alternate methods such as the use of
   "Water-Chex" for chlorine, are normally used at the cannery to
   determine chlorine concentration in the water.  Chlorine dosage is
   then manually adjusted on the basis of that reading.

   Automatic monitoring and control systems, currently available,  con-
   sist of four major components; an analyzer, a recorder,  a controller
   and an automatic valve on the chlorinator to adjust chlorine dosage.
   These automatic chlorine monitor/controllers are particularly useful
   in recirculated cooling water  systems.

   lodophors (surfactant-iodine complex) have been in use for several
   years as sanitizing agents. However, the practical  experience with
   these compounds for the specific application of disinfecting container
   cooling water is extremely limited.  Our study of the very few cooling
   systems using iodophors has  revealed some shortcomings.  An example
   is the adverse effect on the characteristics of the water exerted  by the
   phosphoric acid, and organic  surfactant  contents of the iodophor. The
   first caused the pH range to drop to 2. 9  - 4. 8 in the cooling water, and
   the latter increased the COD  range from 0. 0 - 281. 0 ppm to 470. 0 -
   969.0 ppm.  Therefore, an in-depth stu4y of the effectiveness of these
   compounds, under typical production conditions, is necessary  betore an^ con-
   clusions can be drawn.

   Chlorine Dioxide should not be considered as a direct replacement for
   chlorine in all cases  (7 ).  The advantage of C1O2 is that  it offers better
   germicidal efficiency in situations where chlorine is adversely affected
   by conditions that exist in the water to be treated. Persistently  high
   content of organic matter, especially phenolic and nitrogenous com-
   pounds, and excessively high  pH are mainly the adverse conditions that
   affect chlorine.  These conditions are not normally encountered  in con-
   tainer cooling systems.  Application of C1O2 also involves some  cost
   and safety consideration.

3.  Regulations;
   For the low-acid food  processors, the GMP regulations  (CFR 21:
   113. 60) advises that  cooling water be chlorinated as necessary so
   that there is a measurable free chlorine  residual, or its equivalent
   of other safe chemicals, in the water  at the discharge end of the
   cooler.  This regulation is currently under revision  by FDA and  is
   expected to be mandatory.

   In single-pass systems, a  concentration  of at least 0.5  ppm of resi-
   dual chlorine, measured at the  discharge point,  is adequate (2,6).


                                     130

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Recirculation of cooling water normally requires higher concentra-
tions due to the potential build-up of organic and inorganic matter,
and of the bacterial population.  The layout of the system, the type
of coolers and the characteristics of the water used therein deter-
mine the  required level of residual  chlorine.  The results of our
study show that a range of 2. 0 - 4. 0 ppm is  normally adequate.
When these  ranges of residual chlorine are constantly maintained in
the cooling water,  bacterial population is not expected to exceed 100
colonies/ml in most cases.  At this recommended max level of con-
tamination (3,6 ), occurrence of leaker spoilage is very unlikely
and bacteria of public health concern are seldom encountered.

Section 110. 80 of the GMP is another regulation that determines
the purpose for which cooling water could be reused (4 ).  It states
that ".  .  . water shall  not be reused for washing,  rinsing or con-
veying food products in a manner that may result in contamination of
food products. " This means  that cooling water containing chemicals
such as rust inhibitors  and others,  should not be reused for purposes
other than container cooling regardless of its  good microbiological
quality ( 6 ).

Awareness of Potential Problems Pertinent to Certain Types  of
Coolers;
Water samples collected from systems in which containers are cooled
exclusively  in Still Retorts were of  excellent bacteriological quality.
High TPC was encountered only when there was no detectable residual
germicide in the water. Container  cooling in a  still retort is a batch-
type operation. Therefore,  the cooler is  quite accessible for inspec-
tion and cleaning,  and build-up of food residues inside the cooler is
easily avoidable.
                                               •
The operation of Continuous Pressure Coolers is different.  Circum-
stances may allow  food residue from  the exterior of filled, processed
cans to wash off and accumulate in the cooling water.  Occasional me-
chanical jams which cause containers to burst within the cooler, pose a
major source of organic contamination of the  cooling water.  Over-lub-
rication of the moving parts of the cooler  is another source of such a
contamination.  The presence of organic matter in high concentrations
not only provides nutrients for bacterial growth in  the cooling system,
but also reduces the germicidal effectiveness of the disinfectant,  pre-
sent in the water,  through chemical reactions.  Reaction with chlorine
residues, for instance, is a good example.  Furthermore,  build-up of
suspended solids,  whether organic  or inorganic (especially in recircu-
lated water  systems), affords bacteria a type of physical protection
                                131

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 against the action of the germicide present in the water.  Growth of
 certain types of bacteria is also enhanced in these systems by the re-
 latively high temperatures (120-140°F) especially in inadequately dis-
 infected water.

 When these conditions exist," leaker spoilage, especially of largest
 and smallest can sizes, is frequently encountered.  Therefore,  it is
 essential that continuous pressure  coolers be drained, cleaned and
 sanitized on a regular basis.  Of equal importance is  that an adequate
 level of residual chlorine,  or its equivalent, be maintained in the cool-
 ing water in order to assure  tight control of microbial growth in the
 system.

 In Hydrostatic Retorts, cooling water is normally recirculated within
 the system (Fig. VII). After cooling,  water returns to a basin lo-
 cated either inside or outside the structure of the hydrostat.  Cooling
 water is then pumped to the spray nozzles inside the hydrostat's
 cooling leg.  The water in the basin is particularly prone to accumula-
 tion of grease and oil, and build-up of bacterial population.  This situa-
 tion requires the continuous removal of the accumulated organic matter
 and the maintenance of an adequate level of residual chlorine in the
 water.

 Surfaces within the  cooling leg of the hydrostat should be inspected on
 a regular basis. If heavy contamination is evident, surfaces should
 be immediately cleaned and sanitized.  Maintenance of an adequate
 chlorine residual in the discharge may  require direct  injection of
 chlorine into the basin.  Chlorine requirements of the system must be
 determined through a monitoring program in which microbiological
 and other characteristics of the water are considered.

 In various types of Spray Coolers,  there is the potential for the ac-
 cumulation of organic matter and microorganisms on  the various sur-
 faces within the cooler, (e. g. , belt conveyors - pans, etc.).   Breakage
 of glass containers,  inefficient cleaning operations and inadequate
 chlorination of the water are  some of the most common causes of the
 problem.   When spray coolers are  operated in the single-pass pattern,
 the problem is more of an aesthetic nature.  But if cooling water is
 being recirculated,  the quality of the water used to cool the containers
will be significantly affected by the conditions that exist inside the
 cooler.  Again, inspect, clean, sanitize and properly  disinfect the
 cooling water.
                                 132

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u>
    TO SEWCR.
                                  Fig.  VII.  Cooling water system of a hydrostat.

-------
   5. The Use of Cooling Towers;
      It was not within the scope of this project to study in detail the vari-
      ous types and designs of cooling towers.  However,  the following
      guidelines,  for the operation of container cooling systems with cooling
      towers, are offered on the basis of the data acquired and observations
      made.
      (a)   Proper application of chlorine (or other  safe and approved
           chemical) is indespensable.  Chlorine should be applied to the
           water feeding the coolers at a location that provides  sufficient
           contact time between  chlorine and the water in order to enhance
           the germicidal action of chlorine. Adequate mixing must also be
           provided.
      (b)   Chlorine provision to the tower,  itself, and the hot well must be
           maintained.  Periodical slugging of these components with con-
           centrated chlorine solution is necessary to control the microbial
           growth in the whole system.
      (c)   Residual chlorine levels in the water must be frequently moni-
           tored at several points in the system, particularly at the hot well,
          and chlorine dosage controlled so that adequate concentration of
           residual chlorine is constantly maintained in the cooling water.
          An automatic monitor/controller system is quite practical for this
          purpose.
      (d)   When floor troughs are used to collect the discharge from coolers
          and transport it to the hot well (sump),  contamination from floor
          washing and  other clean-up operations must be avoided.
      (e)   Finally, the  system must be drained, cleaned and sanitized  on a
           regular  basis so that  conditions of excessive chlorine demand
          can be avoided and sources of microbial contamination elimin-
          ated.

In conclusion, I'd like to  emphasize the fact that the findings of this study re-
inforce NFPA's previous recommendation that a constant chlorine residual,
or its equivalent,  is necessary to maintain sanitary conditions in cooling
water,  particularly when the water is recirculated.   Nevertheless, chlorina-
tion does not substitute for manual cleaning, proper container closure or
careful post-cooling container handling.

A CKNOWLEDGEMENT

The author gratefully acknowledges the cooperation of the food processors
who participated in this study and the laboratory assistance of Marcia  Seeger
and Chris Merlo of the NFPA.
                                    134

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REFERENCES

1.  Doyle, E. S. Survey of Water Use in California.  Proceedings of the NCA
   Technical Sessions at the 45th Annual Convention.  January, 1952.

2.  Jacob, N. L. Container Cooling Water Systems - A Preliminary Survey
   of Chemical and Microbiological Quality. Annual Report.   NCA Research
   Laboratories.  Berkeley, California,  pp. 50-52. 1976.

3.  Jacob, N. L. Container Cooling Water Systems - An Overview of Chemical
   and Microbiological Quality.  Annual Report.  NCA  Research Laboratories.
   Berkeley, California,  pp. 29-34. 1977.

4.  Katsuyama, A. M.  Immediate Water-Savings Measures.  Proceedings of
   the  Conference on Water Availability and Conservation. Oakland,
   California.  NCA-CLC. pp. 39-49.  April 1977.

5.  Standard Methods for the  Examination of Water and Wastewater.  14th
   Edition.  American Public Health Association.  Washington, D. C.  1975.

6.  Townsend, C. T. and Somers, I. I.  How to Save Water in Canneries.
   Food Ind. Vol.  21, pp. W:ll-12. 1949.

7.  White, G. C. Chlorine Dioxide.  Handbook of Chlorination.  Van Nostrand
   Reinhold Co. , New York.  pp. 596-627.  1972.
                                   135

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                  LOW BOD RECIRCULATION STEAM BLANCHING

                                    by

                 D.  R. MacGregor* and P.  Parchomchuk**
 INTRODUCTION
 The blanching operation is the largest  single  contributor  to wastewater
 BOD in a typical vegetable processing operation.   Several  workers have
 modified conventional steam blanching methods  to  reduce  BOD output by
 various means.   Water blanching,  although widely  used, does not  seem to
 possess the same possibilities for BOD  reduction.

 Among low BOD steam blanching systems which  have  been developed  is the
 hot gas blanching system of Rails et  al.  (1) which achieves very great
 reductions in BOD while maintaining organoleptic  quality and nutritive
 value.   Operating costs are generally higher than hot water er steam blan-
 ching.   A hot gas blanching process has been patented (2)  in which steam
 is  added to the  burning gas to prevent moisture loss from  the product.
 Forced  circulation of the combustion  gas-steam mixture gives a fluidized
 bed effect.

 Another system which significantly reduces BOD production  in the blanching/
 cooling process  is the modified IQB method  (3).   This method reduces effluent
 volume  by reducing steam usage and by using  atomized blancher condensate
 to  replace water in the air cooling section.  The  combination of IQB blan-
 ching with air cooling has  reduced COD production  50% and  effluent volume
 98.6% as  compared to a conventional steam blanch with flume cooling.  Prod-
 uct  quality is good but,  even though  liquid  is added to  the cooling air,
 losses  due to drying during cooling are large.

 In  a study by Lund (4)  comparing  different blanching methods for seven
 canned  vegetables,  an average  of  5.7  Ib of BOD were produced per ton
 of material with  conventional  belt  steam  blanching  compared to 4.4 Ib per
 ton  for IQB blanching.   IQB blanching was found to  be inferior to pipe blan-
 ching for corn while for  other products the blanching method had no signifi-
 cant  effect on product  quality.

 BACKGROUND

 The  object  of the work  being reported here is to remove  from the waste
water stream  all  BOD  produced  in  the blanching process in  a commercially
 feasible  manner.

 Since steam blancher  condensate is  essentially a dilute juice it seemed
 that  a modification  of  juice  concentration technology could be used to
 reduce blancher effluent  to  a  compact concentrated  form.    Concentration of
juices by  evaporation produces  large  quantities of  steam which could then
be used for blanching.
* Food Processing and ** Agricultural Engineering Sections, Agriculture
    Canada Research Station, Summerland, B. C.

                                    136

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Juice concentrators normally use boiler steam to provide energy for evapora-
tion and steam generated is used in succeeding evaporator stages.  In blanch-
ing, where the objective is to produce a maximum amount of steam, a somewhat
different approach is required.  Also use of boiler steam to generate secon-
dary steam involves additional energy losses and capital costs.  For these
reasons, it was decided to utilize a direct fired evaporator for generating
steam.  In our original work several systems in which burning natural gas
was brought into direct contact with the blancher effluent were tried.  These
were not successful because of the large ratio of non-condensible gasses to
water vapor and consequent lowering of condensation temperature.

STEAM GENERATOR UNIT DESIGN AND OPERATION

The final design, of which a pilot plant model was built and tested, con-
sists basically of a gas fired vertical tube and shell thermosyphon heat
exchanger (Fig. 1).  Heat is transferred to the evaporator tubes from the
flame tube using oil (Essotherm N-69) as a transfer medium.  The flame tabe
102 mm in diameter, and is baffled with 25 ram diameter oil filled cross-
tubes.  The unit is surrounded by an insulated shell containing the heat
transfer oil and 17 evaporator tubes 12.7 mm dia. x 1220 mm long.  This
gives a flame tube surface of 0.78 m2 and evaporator tube surface of 0.83 m .
Feed liquid enters through a manifold at the bottom and is carried up the
evaporator tube by the steam generated.  Excess liquid is recycled and the
steam is fed to the blancher where it condenses on the material being blan-
ched and is returned to the steam generator.  Provision is made by means
of a float valve for addition of make up water as needed.  Non-volatile
materials leached from the product being blanched are concentrated in the
steam generator and bled off when a predetermined concentration is reached.
Bleed-off is controlled by a temperature sensor which responds to the
increased boiling point due to increased solids.  An in line refractometer
would be somewhat more sensitive and much more expensive.  A flow diagram
of the system is shown in Fig. 2.

For testing the unit, sufficient quantities of blancher effluent were
collected from commercial steam blanchers and either used immediately or
stored refrigerated at 2°C or frozen at -28°C until needed.  The test blan-
cher consisted of a 20 cm x 120 cm stainless steel wire mesh belt with a
variable speed drive.  Steam was delivered by a perforated pipe spreader
located between the upper and return section of the belt.  The treatment
section of the blancher was enclosed in galvanized metal with rubber flaps
at inlet and outlet to allow product to pass without excess steam loss.
No special provisions,  such as insulation, were made to reduce heat loss
from the blancher.

The general procedure for test runs was as follows: 1) commercial blancher
effluent was fed into the steam generator and the flame was started and
regulated to hold the temperature of the heat exchange oil at 190°C.  2)
steam from the generator was fed into the blancher and any condensate was
returned to the generator.   Excess steam was allowed to waste.  3) when
solids in the generator had built up to a predetermined level (normally
70% T.S.S.  by refractometer)the test vegetable was run through the blancher.
Blanching times were selected to give a negative peroxidase test.  4) feed-

                                    137

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                                             STEAM OUTLET
                                            -BAFFLE
                                             LIQUID RECIRCULATION
                                             HEAT EXCHANGE TUBES
                                             HEAT TRANSFER OIL
                                             COMBUSTION CHAMBER
                                             INSULATION
Fig. 1.  Gas fired steam generator  -  concentrator prevents burning of
         concentrated soluble solids  by  using  intermediate heat transfer
         oil to maintain low tube surface  temperatures.
                                   138

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                          EXHAUST  GAS
        J-k.
     LIQUID-STEAM
      SEPARATOR
                           STEAM
        HEAT
      EXCHANGER
                      TEMPERATURE
                        SENSOR
                                      RAW PRODUCT IN
                        r
CONCENTRATE
BLEED
                                                        BLANCHER
NATURAL
LIQUID
RECIRCULATION
                                                                                  BLANCHED
                                                                                  PRODUCT
                                                                                  OUT
                       MAKE-UP WATER
                                                     RESERVOIR
Fig. 2.  Heat exchanger vaporizes and recirculates effluent back to blancher while concentrating soluble
         solids leached from product during blanching.

-------
 ing in of blancher effluent and bleed off of concentrate continued.   Total
 running time with one product was up to 37 hr (over a five day period).

 During steps (2), (3) and (4) propane consumption,  steam production,  oil
 temperature, generator solids and stack gas temperature were  monitored.   In
 addition during step (3), blanch temperature, time  and product throughput
 were measured.  As well as heating the product with steam,  exhaust gas at
 150°C was discharged through a 35 cm section of  belt to preheat the product
 prior to entering the steam section.

 The unit is  operated with an oil temperature of  190°C.   At  this temperature
 it  generates 19.8 kg of steam/hr or 23.9 kg/m^/hr and uses  1.45 kg of pro-
 pane per hr  to  give an operating efficiency of approximately  71%.  The
 temperature  of  190°C is a compromise between capacity and 'burn on' in the
 evaporator tubes.   Recirculation of liquid in the generator is approximately
 360 1/hr.  This high recirculation rate helps to prevent burn on.  Practical
 blanching rate  was in the neighbourhood of 60 kg/hr.   Heavy loading tended
 to  reduce blancher temperature (the thermometer  was  located in the center
 of  the unit  above the product).   This represents a  blancher efficiency of
 only 39%,  however,  since our main interest was in the steam generator no
 attempt was  made  to improve performance.

 Blanching tests were conducted on asparagus,  corn,  diced carrots, cauliflower
 and brussels  sprouts.   With all products  except  corn it  was easily possible
 to  concentrate  effluent in the steam generator to 70% total soluble solids.
 Corn presented  some problems in that  the  high starch concentration prevented
 concentration beyond 40% and a fine precipitate  (probably protein) which
 tended to  adhere  to metal surfaces was  formed.   In  spite of this no problem
was  encountered with 'burn on'.   Future plans include provision of a screen
 to  remove  precipitates  and particulate  matter washed out  of the blancher.

Blancher  effluent  contains some volatile  aroma compounds  which  are returned
with the  steam  to  the blancher.   In addition  some aromas  are  produced in
 the  steam  generator.   In order to  test  the possibility of off  flavor transfer
 to  the material in  the  blancher,  taste  tests  were conducted.   Samples taken
 from the  same lot  of  vegetables  were  blanched in a laboratory  steam blancher
and  in the recirculation blancher,  these were then cooled in water, packaged
in polyethylene bags  and frozen  at  -28°C.   After approximately  one month
samples were  cooked  and  presented  to  a  ten member panel  in  a  triangle test.
In this  test panellists  were asked  to indicate preference for  the single
or paired  sample.  No significant  difference  was found between  treatments
or in  acceptability.

In summary recirculation blanching  shows real possibility for commercial
application.   It has  the  following  advantages:

     1.  All BOD involved  in blanching  is  removed from the waste water
stream.

     2.  The unit can be  installed  adjacent to the blancher and is respon-
sive to fluctuating steam  demands.
                                    140

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     3.  Fuel efficiency is increased by elimination of heat losses from
boiler flue gases, steam pipes, etc.

     4.  It is a zero pressure system and does not require a stationary
engineer.

     5.  It is adaptable to present steam blanchers with the only modifica-
tions needed being in the steam distribution system.

     6.  It relieves boiler loading and will allow plant expansion without
the need for increased boiler capacity.

     7.  It reduces water consumption and energy costs associated with deli-
very of water.

     8.  The concentrate produced has potential use as an animal feed ingred-
ient.

It is hoped that a prototype capable of producing steam to blanch 1000 kg/hr
will be built and field tested for the 1979 season.
                                  REFERENCES

1.  Rails, J. W. et al. In-plant hot gas blanching of vegetables.  Proc.
      of the Fourth National Symposium on Food Processing Wastes, Syracuse,
      New York, Environmental Protection Technology Series EPA 660/2-73-031.
     (1973)

2.  Smith, T. J.  Dry blanching process.  U. S. Patent 3,801, 715. (1974).

3.  Botnben, J. L. et al.  Integrated blanching and cooling to reduce plant
      effluent.  Proc. of the Fifth National Symposium on Food Processing
      Wastes.  Monterey, California.  Environmental Protection Technology
      Series EPA 660/2-74-058.  (1974).

4.  Lund, D. B. Impact of the individual quick blanch (IQB) process on
      cannery waste generation.  Proc.  of the Fourth National Symposium on
      Food Processing Wastes.  Syracuse, New York.  Environmental Protec-
      tion Technology Series EPA 660/2-73-031. (1973).
                                   141

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                     LAND VS ACTIVATED SLUDGE TREATMENT
                     OF POTATO PROCESSING WASTE WATER

                                      by

                              K. Lynn Sirrine*
 INTRODUCTION
A comparison of treatment systems is discussed for the treatment of potato
processing waste water.  The intent of the paper is to present actual
problems associated with the treatment of potato processing wastes using
the activated sludge treatment method and the eventual conversion to land
treatment of these wastes.

BACKGROUND

The water pollution problem in some areas of Southeastern Idaho became very
critical during the winter and spring of 1960-61 at which time approximately
a quarter of a million fish were killed in the Milner Reservoir portion of
the Snake River.  In addition to the fish kill, a septic condition was
created in the river and the water quality for domestic use was endangered.
The Snake River and its tributaries above the Milner Reservoir constitute
a major drainage system in Southeastern Idaho.  Located along the banks
of the Snake River and its tributaries above the Milner Reservoir are numer-
ous municipalities and industries some of which discharged portions of their
waste into these streams.  The capacity of this river system to tolerate
the waste disposal load placed upon it was reduced due to decreased water
in storage and increased use of these waters for irrigation.  Because of
the waste load and the low water flow in the river, the aforementioned
pollution condition did develop and the State Board of Health requested
that all contributors try to do something to reduce the waste being dis-
charged to the streams.  The potato processors of Idaho in the spring of
1961 immediately organized a committee which largely consisted of technical
personnel representing all of the major potato processing companies in the
State.  This committee later became known as the Engineering Committee of
the Potato Processors of Idaho Association.

After making an extensive literature search  and running a series of compre-
hensive laboratory studies, the Engineering  Committee decided to verify their
laboratory findings in a full  scale pilot plant waste treatment facility in
October of 1962.  This study was operated until March of 1963.


* The R. T.  French Company, Shelley, Idaho
                                     142

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Since potato processing was a relatively new industry, very little infor-
mation was available concerning the treatability of potato waste material.
As a result, the industry encountered many different taxing problems which
required an all out effort to solve.  This initial pilot plant study, which
was conducted at the R. T. French Company in Shelley, Idaho, was routinely
reviewed and visited by engineers and technical people from all over the
United States who were seeking information concerning our research work.
The Engineering Committee won the coveted "Air and Water Protection Award"
for 1963 by the presentation of a summary report on this study to the
Water Pollution Control Federation at a meeting in Seattle, Washington.

The Potato Processors of Idaho spent about $35,000 to $40,000 in time and
material on this primary treatment study which was completed in six months.
By November of 1963, all 15 potato processing plants located in the critical
area of the Snake River had installed primary treatment plants.  The
installation of these plants decreased the potato processing pollution
load to the Snake River by about one half and cost the potato processing
industry in Idaho about 3 to 3.5 million dollars.  In other words, the
potato processing industry quickly responded as responsible citizens of
Idaho to meet the State Board of Health's request for all contributors
of pollution to reduce their pollution load to the River.  After com-
pletion of the primary treatment studies, work immediately began on
secondary waste treatment.  The activated sludge treatment technique
appeared to give the highest degree of treatment on the potato processing
waste waters.

ACTIVATED SLUDGE

In 1968, a secondary waste treatment system was constructed under a
federal grant, being reported on in report number 12060EHV at the
R. T. French Company in Shelley, Idaho, 12/70, to treat potato processing
waste waters.(')  About 50 to 60% of the waste water requiring treatment
came from the potato peeling operation.

Design factors for the activated sludge treatment system included two
aeration basins.  Aeration Basin 1 holds 1.25 million gallons and normally
contains three 50-hp floating mechanical aerators.  Aeration Basin 2 holds
2.5 million gallons and normally utilizes six 50-hp floating mechanical
aerators.  Both basins have a water depth of 16 feet.  The design BOD
loading is 28 lb/1,000 cu ft/day when the two aeration basins are operated
in parallel.  The aeration basins are constructed of earth and were lined
with PVC (polyvinyl chloride).  The bottom of the basins were sloped to
prevent forming pockets for entrapment of water or gas.  A sun-resistent
Hypalon plastic sheet was placed around the perimeter of the basins to
protect the PVC from exposure to sunlight.

The secondary clarifier is 70 feet in diameter and has a 12-foot side
water depth.  The clarifier has a rapid sludge withdrawal mechanism.
The hydraulic overflow rate is 325 gal/sq ft/day at the design flow of
1.25 mgd.
                                    143

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                 SECONDARY TREATMENT FACILITY  DESIGN  FACTORS
 INFLUENT PUMPS
      Number
      Type
      Capacity
         Each
         Total
      Total  Head
      Constant Speed

 SLUDGE  RECIRCULATION  PUMPS
      Number
      Type
      Capacity
         Each
         Total
      Total  Head
      Constant Speed

 WASTE SLUDGE  PUMP
      Number
      Type
      Capacity
      Total  Head
      Speed
      Dri ve

AERATION  BASINS
      Number
      Type
      Volume of Basin  1
      Volume of Basin  2
      Basin  Water Depths
      Basin  Side Slopes
      Basin  Freeboard
      Basin  Lining

      Number of Aerators, Basin 1
      Number of Aerators, Basin 2
      Design Organic loading
              Centrifugal

              1,300 gpm
              2,600 gpm
              27 feet
              870 rpm
              Centrifugal

              435 gpm
              870 gpm
              18 feet
              870 rpm
                        1
    Positive displacement
              100 gpm
              46 feet
              550 rpm
         Variable - speed


                        2
                  Earthen
     1.25 million gallons
      2.5 million gallons
              16 feet
                  2:1
               2 feet
PVC with Hypalon cover in
         sun-exposed area
                        3
                        6
  28 Ib BOD/1,000 cu ft/d
AERATION EQUIPMENT
     Number Aerators in Aeration Basins                         9
     Type                           Floating pump type mechanical
                                   surface aerators with variable
                               oxygen transfer-power draw feature
     Oxygen Transfer Capacity
                                       75 pounds per hour each in
                                aeration basins with mixed liquor
                                   suspended solids = 4,000 mg/1,
                       operating elevation = 4,627 ft. above MSL,
                                    temperature at 20 degrees C.,
                                   Alpha = 0.85, Beta = 0.90, and
                            operating dissolved oxygen =1.5 mg/1
                              144

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SECONDARY CLARIFIER
     Number                                                        1
     Diameter                                                70 feet
     Side Water Depth                                        12 feet
     Mechanism Type                  Multiple port hydraulic suction
     Design Flow                            1.25 million gallons/day
     Overflow Rate at Design Flow                  325 gal/sq ft/day
     Detention Time at Design Flow                         7.2 hours

The plant was a modern plant utilizing mechanical floating aerators,
but did not have sludge wasting equipment.  The plant was loaded at
an average load of 14,100 Ibs of BOD/day.  D.O. levels of around
1 mg/1 were easily maintained.  Even though the influent pH was rather
high (9.5 to 10.5) the pH buffered easily without the addition of
chemicals.  The process water temperature ran about 21  C (70  F) and
was cooled to about 7.2  C (45  F) through operation of the aerators.
Numerous mechanical problems were encountered and we soon realized
that considerable maintenance attention was needed to keep the equip-
ment operational.

The major problem encountered with the activated sludge treatment
system was in the clarification of the mixed liquor suspended solids.
Low D.O. operation seemed to produce filamentous organisms that further
hindered the clarification process.  As designed, the facility would  not
meet the effluent requirements for discharge to the Snake River due to
suspended solids and BOD concentrations, although if the solids were
removed, the BOD would also be in exceptable limits.  Even with these
problems, this plant won an award for design and for development of
operating parameters for activated sludge treatment of potato processing
wastes.

With the research study finished and the necessity for operation of
the facility with an effluent of good quality on a day to day basis,
it became evident that this system would require additional expenditures
to improve clarification of the mixed liquor.  Also, proper sludge
handling equipment had to be added.   We felt that changes and additions
to the facility would cost about $350,000 and after spending this much
we would still be faced with:

1.  More stringent effluent controls in the future.
2.  The possibility that clarification of the effluent could not be
    accomplished at a reasonable cost.
3.  Even with sludge handling equipment, we would have a residue to
    dispose of.
4.  Increased operating costs due to energy and labor.
5.  Even more additions in the future.

LAND TREATMENT

An evaluation of various modifications to the activated sludge treatment
system was made.  During these evaluations, it became more apparent that


                                   145

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 perhaps other treatment techniques  should be  looked  into.  One  system,
 land treatment,  was receiving some  success in  the  state.  After an
 evaluation of this technique, we found  that we would be able  to purchase
 land, and install  a land treatment  system for  less expense than modifi-
 cations to the present facility.  In  addition  to the reduced  capital
 expenditures, we also found that the  operating costs would be less and
 that a crop of grass hay could be taken from the land treatment system
 which would further reduce  our operating costs.  Added to these benefits,
 we would eliminate our waste water  discharge to the  Snake River.

 Our Shelley land treatment  facility consists of 164  acres of  land
 divided into 22  sub fields  of about 7.5 acres.  The  land has  been leveled
 and graded to a  specific grade,  diked and seeded with a mixture of grasses.
 The water is distributed over the land  by a network  of sub surface and
 surface pipes.   A peeler modification was made in  the processing plant to
 reduce the sodium concentration  in  the  waste water.   Waste water
 characteristics  are:
      1.   COD   3,000 to 4,000 mg/1
      2.   BOD/COD ratio   0.83
      3.   pH   6.5  to 7.5
      4.   Temp.   18°C (65°F)
      5.   Total nitrogen  100 mg/1  (as N)
      6.   Ammoniacal  nitrogen   10 to  15 mg/1   (as  N)
      7.   Nitrates   1  to 2 mg/1   (as N)
      8.   Iron    2 to 3 mg/1
      9.   PO.  5 to 7 mg/1   (as  P)
     10.   Flow 1.15 MGD
 Operation of the system is  quite simple,  as one sub  field is  watered for
 24 hours.   The fields are watered in  rotation  taking about 22 days for
 a  cycle,  dependent upon weekend  operation.  Organically, we are loading
 the land  at about   175 Ibs  of COD/acre/day.  Nitrogen is about  5.8 IDS
 of N/acre/day.   We operate  for about  230  days  for  a  total organic load
 of 40,250 Ibs/year and a nitrogen load  of about 1,334 Ibs/year.  We
 harvest about 4  tons/acre of hay that runs  about 13% protein.   Howeve
 most  of the nitrogen  is removed  through denitrification in the  soil.
 COD removal  is excellent, about  96% is  removed after percolation through
 6  feet of  soil.

 Cost  Comparisons

      Cost                         Activated Sludge        Land Treatment
 1.  Labor,  operation                $14,200                  $4,600
 2.  Labor,  farm management              —                    22,000
 3.  Power                             25,000                     700
4.  Maintenance
          Labor                       8,000                   4,500
          Parts                       6,000                   1,000
5.  Solids Disposal                Not constructed
6.  Laboratory supplies               7,000                   5,000
7.  Operating supplies          	4,000	              500
                  Sub total           64,200                  38,300
          Income                	—	           23,000
                  Total              64,200                  15,300
                                    146

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No cost data is available for the disposal of waste activated sludge
from the activated sludge plant.  The estimated total  investment for
the activated sludge system without the demonstration  project was
$431,379 in 1968.  This estimate does not include sludge wasting faci-
lities.  Sludge wasting was estimated at $350,000, so  the total  plant
costs would have been around $780,000 in 1968.

The land treatment system cost $350,000, which included the cost of
the land.  Peeler changes in the processing plant cost $160,000  for
a total investment of $510,000 (1973).  The peeler changes also  reduced
the organic load by about 30% and increased the amount of product being
sold as cattle feed from the primary waste plant.  This increase only
amounted to about $6,000/year, which would not justify the peeler change
without the waste treatment need.

OPERATING PROBLEMS

The activated sludge system was a high maintenance plant.  The more the
equipment added and operated, the higher the maintenance costs.   The
floating aerator motors being the # 1 maintenance problem.  Problems
are also encountered with too high a suspended solids  concentration in
the clarifier effluent.  The suspended solids separation being the # 1
operating problem.  Under good conditions an exceptable effluent could
be achieved.  However, seldom was the effluent quality good enough to
meet the discharge permit requirements.  At times, odors from the facility
were offensive to nearby residents.

These problems can be overcome either through equipment additions or
modifications or through operation, chemical additions and etc.

Land treatment systems have to be designed for the hydraulic and
organic load placed on them.  The water distribution system used affects
design with respect to field grading, etc.  Assuming that the system
has been designed for waste treatment and is not merely a disposal
area, problems can still develop.

A poorly designed system will have problems with odors, insects, ponding,
poor percolation, poor water distribution, killing of grass, etc.  A
well designed system may have problems with odors and water percolation
and build up during the winter operation in cold climates.  The design
of the facility is more important than one might think.  The odor
problem being the major problem, especially during the spring thaw
period of say March and April.  Odors can be suppressed by chemical
additions, pipe line aeration and some changes in rotation of field used.
Good grass cover helps as does a green buffer of tall  shrubs and trees
around the fields.  Winter operating problems can be eliminated through
proper design considerations.

SUMMARY

An evaluation of our objectives concerning waste treatment revealed that
the activated sludge treatment facility was not giving us the service

                                   147

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that we wanted.  It almost seemed at times that we were no longer a
potato processor, but a waste treatment facility.

By taking a fresh look at the situation and by obtaining the views
of two outside consultants*, we were convinced that we were going
in the wrong direction.

Since regulatory agents and agencies are not defined for all time,
regulations change.  A waste treatment facility must be designed with
enough flexibility that it doesn't become a burden on the owner and
that he is not continually burdened with expensive modifications,
additions and operation.

Land treatment of our potato processing waste water has given us the
flexibility and simplicity that we need.  Some problems still exist
but are reasonable.  Hopefully, the benefits of this type treatment
system to the food processor are seen by the regulatory people and
there use considered and not placed in jeopardy by new unnecessary
regulations.
   Dr.  Dale Carlson, University of Washington, Seattle,  Washington
   Dr.  W. Wesley Eckenfelder, Jr., Vanderbuilt University,  Nashville,  Tenn.
                                 REFERENCES
 1.  Aerobic Secondary Treatment of Potato Processing Waste Water
     Pollution Control Research Series # 12060EHV 12/70

 2.  Staff Draft Report, National Commission on Water Quality,
     November, 1975

 3.  Treatment of Potato Processing Waste Water on Agricultural  Land:
     Water and Organic Loading and The Fate of Applied Plant Nutrients
     by J. H.  Smith, C. W. Robbins, J. A. Bondurant and C.  W.  Hayden
     Soil  Scientists, Agricultural Engineer and Biological  Technician
     USDA-ARS-WR
     Snake River Conservation Research Center, Kimberley,  Idaho
                                    148

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                  A DESIGN PROCEDURE FOR LAND APPLICATION

                                     by

                E.J. Kroeker*, A. Lamb*, and J.M. Haskill**
INTRODUCTION
Land application of wastewater began long before the development of today's
complex treatment plant techology.  Use of effluent for a beneficial purpose
was reported in Germany in the sixteenth century and from that beginning the
application of sewage effluents to farmland was practiced in continental
Europe and England.

Land application approaches have a great deal of potential for alleviating the
wastewater management problems facing the food processing industry.  The
problems become especially acute for those plants located in relatively small
communities whose municipal sewage treatment plants are not able to handle the
highly concentrated wastewaters usually produced by food processing plants.
Where land is readily available at reasonable cost, land application provides
an attractive alternative to wastewater treatment and disposal.

In addition to providing a means of wastewater renovation and removal, land
application provides a means of recycling nutrients and water through cover
crop irrigation and groundwater recharge.  Land application disposal of waste-
water is also usually less energy intensive than today's mechanical treatment
processes.

Figure 1 summarizes the important steps in the selection, design and imple-
mentation of land application systems for wastewater treatment.  This paper
will discuss various types of land application systems currently used for
treatment of various food processing wastewaters, mechanisms of wastewater
treatment in these systems and the importance of each of the major design
variables; it will conclude with a brief description of a design methodology
which should be followed in the selection and design of such systems.

METHOD OF LAND APPLICATION

Most land application systems used in the food-processing industry employ one
of the following surface application methods illustrated in Figure 2:

1.   irrigation
2.   overland flow
3.   infiltration filtration
*  Project Engineer and Director, Environment Division, Stanley Associates
   Engineering Ltd., Edmonton, Alberta
** Program Engineer, Water Pollution Control Directorate, Fisheries and
   Environment Canada, Ottawa, Ontario


                                     149

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SMCinCATION OF
TREATMENT OBJECTIVES


	 L_ •• 1
PROCESSING- PL ANT
E"LU£NT CHARACTERISTICS
o) FLOW RATES
nl BOD a coo
e) T D S
e] s s
• ) N.P,
f) pH
g) TOXIC ELEMENTS
h) TEMPERATURE
i) BAOER'A / VIRUSES
|) PARISHES /INSECT VECTORS
») COLOUR
1 ) SAN
















CLIMATE
CHARACTERISTICS
o) MONTHLY 01 SEASONAL
TEMPERATURE DISTRIBUTION
t) GROWING SEASON LENGTH
c) PERIOD Or FREEZING
«) DIRECTION a SPEED Of
PREVAILING WINDS
• ) TOTAL ANNUAL PRECIPITATION
fl MAXIMUM a MINIMUM
PRECIPITATION
|) RAINFALL DISTRIBUTION
H STORM INTENSITIES
i) TOTAL ANNUAL SNOWFALL
, ) SNOW DEPTH
t) DURATION OF SNOW COVER















SOIL - PLANT
SYSTEM CHARACTERISTICS
SOIL
• ) PERMEABILITY
b) INFILTRATION RATE
C) AVAILABLE WATER CAPACITY
4) CATION EXCHANGE CAPACITY
t) GROUNOWATER TABLE
PLANT
•) WATER REQUIREMENTS
• ) NUTRIENT REQUIREMENTS
c) TOLERANCE TO
TOXIC SUBSTANCES
«) MARKET VALCE
t) MANAGEMENT REQUIREMENTS
1 i
Fig









\ i
ECONOMIC ANALYSIS
] '
SPECIFICATION Of
CONSTRAINTS
o) ECONOMIC
» OPERATIONAL
C) ENVIRONMENTAL

1 1
IMPLEMENTATION
1 I
EVALUATION

ure 1. Flow diagram of the
decision making process.





CHOICE OF CATEGORY AND
METHOD OF LAND APPLICATION
i
PRE-TREATMENT REQUIREMENTS
|
COVER CROP SELECTION
t
LOADING RATE DETERMINATION
• ) HYDRAULIC
t) ORGANIC
C) NUTRIENT (N,P|
«) INORGANIC
|
SELECTION OF
LIMITING LOADING RATE
*
DETERMINATION OF
HYDRAULIC APPLICATION RATES
AND IRRIGATION SCHEDULES
t
DETERMINATION Of
BUFFER ZONE REQUIREMENTS
t
LAND-FORMING REQUIREMENTS
*
EFFLUENT COLLECTION
t
STORAGE REQUIREMENTS
*
DISTRIBUTION SYSTEM DESIGN
t
MONITORING REQUIREMENTS
150

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                            EVAPORATION
SPRAY OR
SURFACE
APPLICATION
  ROOT ZONE


  SUBSOIL
                                                               SLOPE
                                                              VARIABLE
                                                               DEEP
                                                               PERCOLATION
                                IRRIGATION
                             EVAPORATION
                                       -GRASS AND VEGETATIVE LITTER


                                              SHEET FLOW
                                                              r RUNOFF
                                                             I  COLLECTION
                              OVERLAND  FLOW
                              SPREADING BASIN
              INFILTRATION
    ZONE  OF AERATION
    AND TREATMENT
    RECHARGE  MOUND
                                              SURFACE APPLICATION
PERCOLATION  THROUGH
UNSATURATED ZONE
                                                      NEW WATER TABLE
                             /   III1    \
                           >     HH     X
                                                      OLD WATER TABLE
                         INFILTRATION  PERCOLATION


              Figure 2.  Surface  land application approaches,

                                  151

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 Irrigation

 Irrigation is  the controlled discharge  of effluent, by  spraying or surface
 spreading, onto land to support plant growth.   The wastewater  is  "lost"  to
 plant  uptake,  to air by evapotranspiration,  and to groundwater by percolation.
 Treatment of the wastewater generally occurs after passage  through the first
 60  to  120 cm (2 to 4 feet)  of soil.

 The method of  application depends  on the soil,  the type of  crop,  the climate,
 and the topography.   There  are three established methods of irrigation of
 wastewater:

 a)   spray irrigation
 b)   flooding
 c)   ridge and furrow

 These  are illustrated in Figure 3.

 Spray  Irrigation

 In  the spray irrigation method,  effluent  is  applied above the  ground surface
 by  a sprinkler system in a  manner  similar to rainfall.   The spray is developed
 by  the flow of effluent under pressure  through  nozzles  or sprinkler heads.
 The important  components of a spray  irrigation  system are the  pump, supply
 main,  laterals,  risers  and  nozzles or sprinkler heads.   The spray system can
 be  portable or permanent, moving or  stationary.

 Flooding

 Flooding  is the  inundation  of the  land with  effluent.   The  depth of inundation
 is  determined  by  the slope,  choice of vegetation and the type  of soil.  The
 land has to be  level  or  nearly level  so that  a uniform depth  can be maintained.
 The land  needs drying periods  so that soil clogging does not occur and the
 cover  crop has  to be  able to  withstand periodic  flooding.

 Ridge  and Furrow  Irrigation

 Ridge  and furrow  irrigation is accomplished by gravity  flow of effluent
 through furrows, with subsequent seepage  into the ground.  Utilization of this
 technique is generally  restricted to relatively  flat land, and extensive pre-
paration  of the ground  is required to create ridges and furrows whose width
 and  depth vary with  the  quantity of wastewater and the  type of soil.

Although  irrigation is  the most  common method of land application utilized,
its applicability to  a  particular location is most suitable if the following
site conditions exist:

1.   Warm arid climates  are ideal.   More severe climates are acceptable if
     facilities are provided  to handle freezing and/or wet conditions.

2.   Slopes up to 15 percent are acceptable provided runoff or erosion is


                                     152

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               RAIN DROP ACTION
       ' 4- — — "r   T ---
      --/tf:/\.rr.:. \ cr^
       S"' ' ...•»... I ».. . • , *

         ~
 irirrrrrrnTmT
        SPRAY  IRRIGATION
                   COMPLETELY FLOODED
                ' \ '. ••• -\
                -^r  ; V
          FLOODING
^€?%jSi% --$^%^te^
»>*^    j/TV/'« .• >• ''.'f   "  \ ^ . '••'"•''. k     ^is»
         RIDGE a FURROW
     Figure 3. Methods of irrigation.
             153

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      controlled.

 3.    Loamy  soils  are  ideal but most soils  from sandy loams to clay loams are
      suitable.

 4.    Well-drained soil is required.  Where  these conditions do not exist the
      site may be  made suitable by  incorporating underdrainage systems.

 5.    Soil depth of  1.5 to 2 m  (5 to 6 feet) is required for plant root develop-
      ment and wastewater renovation.

 6.    Geologic formations which may provide  direct connection to groundwater
      must be avoided.

 7.    A minimum depth  to groundwater of 1.5  m  (5 feet) is required to maintain
      aerobic conditions, provide wastewater treatment and prevent surface
      water-logging.   Where this condition does not exist naturally, ground-
      water  pumps  or artificial drainage may be used to lower the water table.

 8.    Typical land area required for a 4540  m  per day (1 Imgd) irrigation
      system is 40 to  80 ha (100 to 200 acres).  Buffer zones are frequently
      required for spray irrigation.

 Overland Flow

 Overland flow is  the  controlled discharge,  by spraying or other means, of
 effluent onto the land with a large portion of the wastewater appearing as
 runoff.  As the effluent flows down the slope a portion infiltrates into the
 soil, a small amount  evaporates and the remainder flows to collection channels.
Wastewater  treatment  occurs by filtration of suspended solids by surface
 vegetation  and by oxidation of the organic matter by the bacteria living on
 the vegetation litter.

 Soils limited in  permeability such as clays and clay loams are especially
 suited to overland flow.   The land for an overland flow system should have a
moderate slope (between two and six percent) and the surface should have no
mounds or depressions.

The following conditions are necessary for a site to be especially suitable to
overland flow treatment of wastewater:

1.   Soils with minimal infiltration capacity such as heavy clays, clay loams,
     or shallow soils underlain by an impermeable subsoil are suitable.

2.   A minimum topsoil depth of at least 15 to 20 cm (6 to 8 inches)  is
     recommended  in order to establish a cover crop.

3.   Slopes of 2 - 4% are required to allow the applied wastewater to flow
     slowly over  the soil surface to the runoff collection system.

4.   Warm arid climates are ideal.   More severe climates are acceptable if
                                     154

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     facilities are provided to handle freezing and/or wet conditions.

5.   If reuse of the runoff is not possible, then a waterway or drainage
     system must be constructed to transport the effluent from the site.  This
     effluent must meet the federal and provincial standards for discharge
     into receiving waters.

6.   A minimum depth to groundwater of 1.5 m (5 feet) is required to maintain
     aerobic conditions for plant growth.  Where this condition does not
     exist naturally, groundwater pumping or under drainage may be used to
     lower the water table.

7.   Land requirements typically range from 10 to 45 ha (25 to 110 acres)  for
     a 4540 m^/day (1 Imgd) spray irrigation system; additional buffer zones
     may be required.

Infiltration Percolation

The infiltration percolation method of wastewater treatment is similar to  inter-
mittent sand filtration.  The major portion of the wastewater enters the
groundwater although there is some loss to evaporation.  Soils with high in-
filtration and permeability rates such as coarse textured sands, loamy sands
or sandy loams are required.

This process has been developed for groundwater recharge and thus the distinc-
tion between treatment and disposal for this process is quite fine.  Some
treatment occurs during the infiltration percolation process as the wastewater
passes through the aerobic layer.  The primary purpose of this method is to
provide physical removal of suspended solids and bacteria.

The applicability of infiltration percolation for land application treatment
of wastewater is quite restricted mainly because of soil permeability con-
straints.  The following discussion summarizes the major criteria for the
suitability of infiltration percolation treatment:

1.   Well-drained soils such as sand, sandy loams and loamy sands are required.
     Very coarse sand and gravel are not ideal because they allow wastewater
     to pass too rapidly through the first few feet where the major biological
     and chemical wastewater treatment occurs.

2.   A minimum depth to groundwater of 4.5m (15 feet) is recommended.  Where
     this condition does not exist naturally, groundwater pumping or artifi-
     cial drainage may be used to lower the water table.

3.   The site should be flat or gently sloping.  Too much slope may create
     lateral percolation.

4.   Land requirements typically range from 1 to 2 ha (2.5 to 5 acres) for a
     high-rate system to 8 to 24 ha (20 to 60 acres) for a low-rate system for
     a 4540 m^/day (1 Imgd) wastewater application rate.
                                     155

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TREATMENT MECHANISMS

The design and successful operation of any wastewater treatment plant is
predicated upon an adequate analysis of the wastewater being treated and upon
an understanding of the treatment processes to be employed.  In land appli-
cation systems wastewater treatment and removal occurs at or below the soil
surface.  The efficiency of treatment and removal is reflected by soil-plant
system characteristics, wastewater constituents and by the atmospheric climate.

Physical Processes

Many complex physical, chemical and biological processes take place to change
the characteristics of wastewater applied to a soil.

Filtering or retention of solids close to the soil surface is the major
physical treatment process.  The size of particles removed is a function of
the soil pore size and configuration and of the nature of the particles in the
wastewater.  The larger suspended solids are removed from the wastewater but
bacteria and viruses can travel considerable distances through soils.  It
should be pointed out, however, that overloading with suspended material and
the subsequent creation of anaerobic conditions may have adverse effects on
the hydraulic capacity of the system.

The relative importance of soil physical processes in wastewater treatment and
removal is a function of the land-application technique:

1.   In irrigation systems, water removal by the soil physical processes is as
     important as the chemical and biological processes also taking place.

2.   For overland flow methods of wastewater treatment, the soils are usually
     quite impermeable and very little wastewater infiltration results.
     Filtering of solids at the soil surface is therefore minimal.

3.   In infiltration percolation systems,  filtration of suspended organic matters
     from the wastewater is a very important wastewater renovation process.

Chemical Processes

Two important chemical soil processes partially responsible for wastewater
treatment are adsorption and chemical precipitation.  Soils containing clay or
organic matter attract and retain (adsorb) ions possessing a positive charge
(cations).  The ability of the soil to adsorb cations is important to plant
growth and wastewater treatment.  For example, important plant nutrients such
as potassium and ammonia which are usually present in significant concentra-
tions in wastewater can be retained on soil particles for adsorption and made
available for plant nutrition rather than leaching rapidly through the root
zone and eventually to the groundwater.

Chemical precipitation reactions involving dissolved ions and other chemical
compounds are numerous and exeedingly complex.  Calcareous soils, common in
the prairies or in limestone-derived soils can neutralize acidic wastes
                                      156

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although this may result in the release of relatively soluble salt solutions.
The principal mechanism for removal of phosphorus from wastewater in the soil
is chemical precipitation.

Biological Processes

The most important mechanisms of wastewater treatment in the soil involve
biological transformation.  Some of the groups of soil organisms responsible
for the decomposition of plant and animal materials are bacteria, fungi, acti-
nomycetes, protozoa, worms and insect larvae.  These organisms alter waste
constituents and a high proportion of the chemical constituents, notably carbon,
nitrogen, phosphorus and potassium, are liberated for'plant growth.

Aerobic decomposition of new organic material may be considered to take place
in three stages:

1.   Organisms initially digest the more easily decomposed material, consuming
     oxygen and releasing carbon dioxide and water.  The amount of oxygen
     consumed can be estimated by the five day biochemical oxygen demand test.
     Organism growth rate is rapid during this stage.

2.   The number of organisms declines as the readily decomposed organic mater-
     ial is consumed.  The dead microbial tissue, together with the intermed-
     iate decay products provide substrate for new and remaining organisms.
     This material, together with the more refractory organics in the waste-
     water are degraded to a relatively stable end product known as humus.

3.   The organisms decline to population levels similar to those before
     addition of the wastewater.  However, decomposition of humus by highly
     specialized organisms continues during this phase.

The rate of organic matter decomposition and the nature of the intermediate
and end products depend on the composition of organic matter.  Soil factors,
however, also exert considerable influence.  The presence or absence of
adequate oxygen in the soil is the principal factor in determining the rate of
decomposition and the end products.

Decomposition also occurs under anaerobic conditions but at a slower rate and
often with the production of intermediate compounds having objectionable
odours.  Plant growth will likely suffer under prolonged anaerobic conditions.
Intermittent or partial anaerobic conditions may result in the production of
nitrogen gas and various other gaseous oxides of nitrogen.  This reaction and
the volatilization of ammonia can reduce problems of nitrogen overloading to
some extent.

DESIGN VARIABLES

Soil Characteristics
The foregoing discussion of physical, chemical and biological treatment pro-
cesses illustrates the interacting soil, cover crop, wastewater and climatic
                                      157

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 characteristics  in wastewater  treatment.   Important soil characteristics in
 the  selection and design  of  land  application systems include the following:

 1.    infiltration rate
 2.    permeability
 3.    available water  capacity
 4.    cation exchange  capacity
 5.    depth to groundwater

 Infiltration  rate is  a soil  surface phenomenon which describes the rate of
 water movement into the soil surface.   It  is a direct function of soil pore
 size and moisture content.

 During  initial wastewater application,  the application rate is controlled by
 the  infiltration rate.  The  infiltration rate decreases, however, as appli-
 cation  continues and  approaches a limiting value.  At saturation, this con-
 stant is equal to the permeability of the  least permeable soil layer.

 Most screening of suspended  material from wastewater occurs during infiltration.
 However, the  high concentrations  of suspended solids present in some food pro-
 cessing wastewaters may clog surface soil pores.  Application of wastewater at
 rates beyond  the infiltration  rate for  long periods of time results in anaero-
 bic  conditions.

 Compaction of the soil surface by water droplets in a spray irrigation system
may  greatly reduce pore space volume and seal the surface to downward water
 movement.  The presence of a cover crop to cushion the impact of water drop-
 lets  usually  alleviates this problem.

 Infiltration  rate is  an important variable in irrigation and infiltration per-
 colation systems.  Wastewater application rates which exceed infiltration rates
 and  thus produce ponding  or  surface runoff should be avoided.  Periods of
wastewater application should be  followed by rest periods to allow the surface
 to dry  and prevent the persistence of the anaerobic conditions which give rise
 to surface clogging.

 Permeability  describes the rate at which water and air move through the subsoil.
 It is controlled both by soil texture and structure and is primarily a function
of pore size.  Fine textured and  structured soils generally possess low per-
meability; medium textured and structured soils such as loam or silty loam tend
to have moderate to low permeability.  Coarse sands exhibit the highest per-
meability.  Table 1 summarizes typical permeability rates for various soils.

 Those soils having severely  restricted permeability in the lower part of the
profile are likely to develop a perched water table and tile drains may be
required.  Soils having large pores or fractures transmit water and air rapidly
but may also  transmit contaminants.

Conditions of extreme impermeability in the subsoil horizon may result from
layers of impervious clay beds or rock formations located within several feet
of the soil surface.


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        TABLE 1.  TYPICAL RANGES OF PERMEABILITY AND AVAILABLE
                  WATER CAPACITY ACCORDING TO SOIL TEXTURAL CLASS
Very coarse textured
sand and fine sands
Permeability (cm/hr)
0 to 3% 3 to 9%
2.5 or 2 or
greater greater

Greater
than 9%
1 or
greater
Available
Water Capacity
(cm/m)
4 to 8
Coarse textured loamy
sands and loamy fine
sands
2 to 4
1 to 2.5
1 to 2
 6 to 10
Moderately coarse tex-
tured sandy loams and
fine sandy loams         1 to 2.5

Medium textured very
fine sandy loam, loams
and silt loams         0.8 to 2

Moderately fine tex-
tured sandy clay loams
and silty clay loams   0.5 to 1
Fine textured sandy
clays, silty clays
and clays
              1 to 2
            0.5 to 1
            0.8 to 1
            0.4 to 0.8
            0.4 to 0.6     0.3 to 0.4
.3 to .5
.3 to .4
 <0.3
              10 to 15
              13 to 20
                            15 to 20
13 to 20
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 It is emphasized that the infiltration and permeability  rates are important in
 the selection of methods  for wastewater treatment:

 1.    Soils with high infiltration and permeability  rates are suitable for
      infiltration percolation wastewater treatment.

 2.    Soils exhibiting very low infiltration and  permeability rates can only
      support  overland flow systems.

 3.    Soils exhibiting moderate infiltration and  permeability rates are suitable
      for irrigation systems.

 The available water capacity is defined as the amount of water retained by a
 soil between  the field capacity and  the wilting  point.   Its magnitude deter-
 mines the quantity of water which can be stored  in  the soil for uptake by
 plant roots and it reflects the quantity of wastewater that can be held in
 the soil without being discharged into the groundwater.

 Available water capacity  depends on  soil pore size  and shape and the strength
 of  bonding of the water to soil particles.   Soils can be divided into three
 groups,  depending on the  texture (typical ranges of available water capacity
 are given in  Table 1).

 1.    Coarse texture - low water capacity because of large pores and low sur-
                       face area;  readily drained by gravity.

 2.    Medium texture - high available water capacity with relatively small
                       pores  and medium retention of water.

 3.    Fine texture   - low available  capacity due to large areas and tightly
                       bonded water.

 Cation exchange  capacity  is  a  measure  of the ability of a soil to retain
 positively charged ions such as  the  ammonium ion, calcium, magnesium, potasium
 and sodium.   Both the clay and humus  fractions of the soil are characterized
 by  extremely  small particle  size and by the  presence of a negative electrical
 charge.   The  significance of this  charge is  that oppositely charged ions or
 compounds are attracted and held to  these colloidal surfaces.  The size of the
 soil  colloids  and the magnitude  of the electrical charge determines the cation
 exchange  capacity  of  a soil.

 The cation exchange  capacity serves as  a rough index of reactions which occur
between pollutants  and the soil  surfaces.   In general, the greater the cation
exchange  capacity  of  a soil, the  greater the potential for effective waste
 treatment.

 The groundwater  table  is  the level in  the soil at which free water is present.
Above this  level,  free water movement  is  vertically downward.  At the ground-
water table the  soil becomes saturated  and water movement becomes vertical
and lateral.
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The depth of the soil to groundwater is a major factor in determining water
storage and hence the surface water removal capacity of a land application
system.  In addition, it determines the distance the wastewater will travel
through the aerobic zone where potential contaminants can be filtered out or
removed by biological and chemical mechanisms before the groundwater is reached.

The variation of depth to groundwater throughout the site and variation with
season should be determined prior to the selection of the site and the land
application method.  In order to ensure an aerobic root zone for cover crop
growth, it is preferable to maintain a groundwater level at least five feet
below the ground surface.  Groundwater levels can be controlled by installing
an underdrainage system or by pumping water from wells located close to the
site.

Cover Crop Characteristics

The cover crop increases the capacity of the soil to accept and to treat waste-
water.  Plants protect the soil from erosion losses, encourage and maintain
moisture infiltration, increase soil drying rates through transpiration and
absorb nutrients.  Vegetative cover also has an aesthetic appeal and may
contribute an economic benefit through crop harvest and sale.  Cover crop
characteristics pertinent to the selection and design of land application
systems are the following:

1.   water requirements
2.   nutrient requirements
3.   tolerance of the plant to potentially harmful wastewater characteristics
4.   management requirements
5.   market value

As discussed previously, some of the wastewater which is applied to the soil
is removed by natural drainage into and through the soil pore space.  Plants
provide an additional means for water removal up to several feet below the
surface.  Water moves into the plant roots and upwards to the plant body where
moisture is lost from the leaves by transpiration.  The transpiration rate is
a function of climatic conditions including temperature, precipitation, solar
radiation and wind.  It also depends on the availability of soil moisture and
on such characteristics as rooting depth and the seasonal pattern of root and
leaf development.  The removal of water by both evaporation and transpiration
is described collectively as evapotranspiration.  Important evapotranspiration
factors associated with the cover crop include rooting depth, seasonal pattern
of root and leaf development and other specific factors such as the physical
nature and size of leaf growth.

Rooting depth increases in importance as the length of the resting period in
the wastewater application schedule increases.  As the surface layer of the
soil dries, water will be drawn from successively greater depths.  Plants such
as alfalfa with deep rooting systems can also penetrate impermeable subsoil
zones and thus increase the water infiltration capacity of the soil.

Nutrient removal through crop harvest is the primary mechanism of nitrogen and
                                      161

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 phosphorus  removal  from the  soil  and  depends on the  type of land application
 system.   For  example,  in an  overland  flow  system, both nitrogen uptake and
 denitrification play major roles  in nitrogen removal.  Phosphorus removal,
 however,  is determined by plant uptake since adsorption by the soil is not
 significant.   In contrast, the quantity of nutrients removed by plants may
 be minor  compared to total loadings in an  infiltration percolation system.

 The  quantity  of nutrients which can be removed depends on the type of plant
 cover  and the harvested yield.  Figure 4 illustrates the potential for
 removal of nitrogen and phosphorus in various crops.  Both nitrogen and
 phosphrous are absorbed in greatest quantities by certain species of grasses.
 Harvesting the entire  cover  crop  (for example, corn silage, hay) results in
 greater nutrient removal than harvesting only selected parts (grain, vegetable
 crops) and ploughing the remaining vegetation into the soil.

 Certain chemical constituents of wastewater may be toxic to vegetative growth.
 The  elements  of possible concern  in food processing wastewaters include
 sodium, calcium and magnesium, and various salts such as chloride, sulfate
 and  bicarbonate.

 The  effect of saline solution on plant growth is principally due to changes
 in the osmotic pressure of the solution which influences water availability
 to the plant  roots.  In addition, high concentration of ions such as chlorine
 may  interfere with  nutrient  assimilation by plants.  Plant species differ in
 their responses  to  salinity.

 The  ability of the  cover crop to adapt to  a specific land application system
 and  the labour requirements  for successful crop management are important
 factors in selecting a  cover crop.  The following factors need to to be taken
 into account:

 1.   Tolerance to variable soil moisture conditions, especially frequent
     saturation.

 2.   Soil physical  and  chemical properties.

 3.   Tolerance  to severe  climatic changes such as low temperatures and the
     plant growing  season.

Assistance in the selection of crops  can normally be obtained from local
agricultural  representatives.

Labour requirements for  successful crop management may be critical during all
stages of crop growth.    These include germination, emergence,  and seedling
establishment  in which  favourable soil and moisture conditions are critical
for some crops.

During the growth period, important management factors may include supplement-
al fertilization, well  defined tillage practices,  irrigation scheduling, weed
and insect control and  crop harvesting.  It may also be necessary to re-estab-
lish  or rotate crops from to time when visual checks or yield tests indicate
                                      162

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       CORN  GRAIN




      WHEAT  GRAIN



      CORN SILAGE



    ORCHARD  GRASS




       BLUEGRASS



          FESCUE




REED CANARY  GRASS
                                 100
200
300
                NITROGEN  REMOVED IN  HARVEST  (kg/ha-yr.)
       CORN  GRAIN



      WHEAT  GRAIN



      CORN SILAGE



   ORCHARD GRASS



       BLUEGRASS



          FESCUE



REED  CANARY GRASS
                                 10
20
30
                PHOSPHORUS  REMOVED  IN HARVEST (kg/ha-yr.)
                  Figure 4.  Potential nutrient removal by crops.
                                     163

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 poor productivity.   Specific  cover  crop  requirements and limitations are
 discussed later in this  section.

 The  economic  return from certain  crops may offset some of the operating costs
 of a land application system.   The  return may be substantial in arid regions
 because  the availability of water permits the growth of crops not otherwise
 possible.   In such areas,  limited competition in local markets may add signifi-
 cantly to this monetary  return.

 The  following cover crops  have  been used in land-application systems:

 1.    Small grains,  such  as wheat, oats and barley
 2.    Row crops such as corn,  sugar  beets and vegetable crops
 3.    Sod crops,  primarily  grasses and legumes
 4.    Forests

 Wastewater Characteristics

 Wastewater characteristics may  affect the selection of land application methods
 and  they will usually  affect  the  efficiency of operation of such a system.
 Wastewater characteristics which  should  be determined prior to the design of a
 land application system  are the following:

 1.    Annual and  seasonal wastewater quantities
 2.    Biochemical oxygen  demand  (8005) and chemical oxygen demand (COD)
 3.    Suspended solids  (SS)
 4.    Total dissolved solids (TDS) and electrical conductivity (EC)
 5.    Nitrogen (N)
 6.    Phosphorus  (P)
 7.    pH
 8.    Temperature
 9.    Color
 10.   Toxic elements  (heavy metals,  trace elements, etc.)
 11.   Bacteria  and viruses
 12.   Sodium adsorption ratio  (SAR)
 13.   Oil and  grease

 The  seasonal  and annual  quantities  of wastewater generated by a processing
plant will determine the area of land required to dispose of the wastewater.
 In addition, since wastewater produced during the winter months will usually
have  to be stored, quantities generated  during those months will determine
storage volume requirements.

The biochemical oxygen demand (6005) is a measure of the concentration of
readily oxidizable organic matter in the wastewater.  When the rate of appli-
cation of organic matter exceeds its rate of removal by soil micro-organisms,
clogging of the soil surface may result,thus greatly reducing the wastewater
infiltration rate and producing anaerobic conditions within the soil which
greatly decrease the efficiency of treatment.

Suspended solids in wastewater may cause operational problems such as clogging
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of sprinkler nozzles and soil pores, and the formation of an impermeable
coating over the soil surface.

An excessive rate of application of high IDS bearing wastewaters may cause a
salinity hazard to crops and/or may cause groundwater contamination.  The
salinity hazard to crops can be especially prevalent in arid or semi-arid
regions where the annual evapotranspiration exceeds annual precipitation.
Table 2 summarizes some of the effluent quality requirements for land appli-
cation systems.

Nitrogen and phosphorus may be present in relatively high concentrations in
some wastewaters, especially those from meat and poultry processing plants.
Although both are important plant nutrients, when applied at excessive rates,
they may contaminate the groundwater.

Wastewaters having a pH between 6.0 and 9.0 are generally suitable for appli-
cation to the land since microbial and plant processes are generally most
active in the neutral pH range (6 to 7).

The application of high temperature wastewater (greater than 150 F) to land
may sterilize the soil and thus prevent the growth of any vegetation.

In most wastewaters colour is associated with degradable organic material and
is effectively removed as the water percolates through the soil mantle.  How-
ever, should the colour associated with the wastewater be persistent such as
that associated with lignins, it can leach into the groundwater and effective-
ly contaminate this water source.  This type of groundwater contamination is
difficult to avoid and therefore coloured wastewaters to be applied to the
land should be carefully assessed for ease of colour removal.

Meat and poultry processing wastewaters usually contain significant concen-
trations of pathogenic bacteria and viruses.  Although the soil mantle is
usually quite efficient in the removal of bacteria and viral organisms, some
concern has been expressed recently because of confirmed viral infection
resulting from land application of wastewaters.  When a spray application
system is to be utilized, consideration should be given to the possible trans-
portation of pathogens in aerosols.

The relationship between the principal cations in wastewater, especially
calcium, magnesium and sodium is very important.   When the ratio of sodium to
calcium and magnesium (expressed as sodium adsorption ratio) becomes too high,
the sodium tends to replace the calcium and magnesium ions on clay particles
and has the effect of dispersing the soil particles and consequently reducing
soil permeability.

Wastewaters from meat and poultry processing plants usually contain relatively
high concentrations of oil and grease from cutting, deboning and rendering
operations.  Excessive concentrations may cause severe clogging of the soil-
pores.
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                   TABLE  2.   EFFLUENT  QUALITY GUIDELINES
                                                        (3)
    Problem and
 Related  Constituent
  No Problem
                                           Guideline Values
Increasing Problems
    Severe
 Salinity
 EC   of irrigation
 water, in mmho/cm
 Permeability
 EC of irrigation
 water, mmho/cm
 SAR  (Sodium ad-
 sorption ratio)
 Specific ion tox-
 icity2
 From root adsorption
  Sodium (evaluate
  by  SAR)
  Chloride, me/1
  Chloride, mg/1
  Boron, mg/1
 From Foliar
 adsorption
 (Sprinklers)
  Sodium, me/1
  Sodium, mg/1
  Chloride, me/1
  Chloride, mg/1
less than 0.75    0.75 to 0.30


greater than 0.5  less than 0.5

less than 0.6     6.0 to 9.0
less than 3.0
less than 4.0
less than 142.0
less than 0.5
less than 3.0
less than 69.0
less than 3.0
less than 106
3.0 to 9.0
4.0 to 10
142 to 355
0.5 to 2.0
greater than 3.0
greater than 69.0
greater than 3.0
greater than 106.0
                     greater than 3.0


                     less than 0.2

                     greater than 9.0
greater than 9.0
greater than 10
greater than 355
2.0 to 10.0
1    Assume water for crop plus needed water for leaching requirements will be
     applied.  Crops vary in tolerance to salinity.
2    Most tree crops and woody ornamentals are sensitive to sodium and
     chloride (use values shown).  Most annual crops are not sensitive.
3    Leaf areas wet by sprinklers (rotating heads) may show a leaf burn due to
     sodium or chloride adsorption under low-humidity, high-evaporation con-
     ditions.  (Evaporation increases ion concentration in water films on
     leaves between rotations or sprinkler heads).

Note:  Interpretations are based on possible effects of constituents on crops
       and/or soils.  Guidelines are flexible and should be modified when
       warranted by local experience or special conditions of crop, soil, and
       method of irrigation.
                                     166

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 Climatic Characteristics

 The magnitude of climatic effects in the design of land application systems
 depends on  the category and method of application, the type of equipment used
 and the volume of wastewater applied.  The major climatic variables are the
 following:

 1.   Seasonal and annual distribution of precipitation
 2.   Average seasonal temperatures
 3.   Speed  and direction of prevailing winds

 Precipitation in the form of rainfall, snow and hail will serve to determine
 allowable wastewater loading rates, storage requirements and land drainage
 requirements.

 During the  application season, the land area must be sufficient to dispose of
 incident seasonal precipitation as well as of applied wastewater.  Therefore,
 a water budget for a proposed system must take account of all precipitation
 during the wastewater application period.  All storage facilities must be
 sufficient  to contain any incident precipitation and runoff produced during
 non-application periods.

 The ambient air temperature affects wastewater loading rates and determines
 the allowable length of the application season.  The rates of soil microbial
 reactions are temperature dependent.  The rate of removal of water from the
 soil and cover crop by evapotranspiration is a function of several variables
 including precipitation, wind, availability of soil moisture and vegetation
 characteristics.  However, temperature is the single most important variable.
 Finally, cover crop growth patterns are controlled as much by temperature as
 by moisture availability.

 The prevailing wind directions and speed are important where spray irrigation
 is used and aerosol drift to nearby communities may be a problem.  These wind
 data are useful in predicting buffer zone requirements around the wastewater
 treatment facility.   In addition, prevailing wind direction should be con-
sidered where odour transmission is a potential problem, particularly from
stored effluents.

PROCESS DESIGN

Figure 1 summarizes  the various steps in the design of a land application
system.  Following a preliminary assessment of site characteristics and con-
straints,  one of the three methods of land application discussed earlier
should be selected.   This section summarizes briefly the various design
components for each  of the systems.

Pretreatment Requirements

Pretreatment requirements for food processing wastes may include one or more
of the following processes:
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 1.    Coarse screening for suspended solids  removal
 2.    pH adjustment
 3.    Deodorization
 4.    Biological  pretreatment

 Coarse  screening may  be  required  for removal of solids which clog spray
 nozzles or  for the  removal of  grit  which may accelerate the erosion of pumping
 and  transmission equipment.

 The  three types  of  screens normally used include stationary, vibrating and
 rotating screens.

 pH adjustment is required for  those wastewaters whose pH is outside the range
 of 6 to 9.5.  Typical chemicals used include sodium hydroxide and sodium
 carbonate for acidic  wastewaters, and sulphuric and hydrochloric acid for
 alkaline wastewaters.

 Wastewater  effluent may be deodorized prior to irrigation in those cases where
 odour problems exist.

 Biological  pretreatment may be required by the provincial regulatory agency
 involved in approving the  facility.   Biological treatment processes which have
 been used include anaerobic lagoons,  facultative and aerated lagoons, acti-
 vated sludge, oxidation ditches, trickling filters and rotating biological
 contactors.

 Cover Crop  Selection

 The  choice  of a  suitable  cover crop will depend on one or more of the following
 objectives:

 1.    Maximum water  removal
 2.    Nutrient removal
 3.    Economic return

 Sod  crops such as legumes  and  grasses have a longer growing season than grain
 or row  crops and therefore provide  increased consumptive use of water.   Forests
 also hold the potential for removing  relatively large volumes of water.

 Sod  crops,  row crops and grain crops provide good nutrient removal.   Grain
 crops and row crops may be used to maximize the economic benefits of a land
 application facility.

 Loading Rate Determination

 The importance of regulating the liquid loading rate, the effects of over-
 loading and the climatic constraints to seasonal and annual wastewater
 application rates were discussed earlier.   Soil permeability and climatic
evapotranspiration data should be used to determine the hydraulic loading
 rates for the site.   These rates can then be used to determine land  areal
 requirements and to set up an irrigation schedule.


                                      168

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The wastewater application rate may be limited by the concentration of nitrogen
and/or phosphorus in the wastewater.  The nutrient loading rate to the soil
must be limited such that a balance is reached between the amount applied, the
amount removed by treatment and crop uptake and the concentration permitted to
reach the groundwater.

The effects of organic overloading to the soil were discussed earlier.  Waste-
water application rates should not be so high that clogging of the soil surface
occcurs due to excessive organic application rates.

In most cases either the hydraulic or the nutrient loading rate to a particular
soil will determine the allowable wastewater application rate. Once the rate
has been established, an application cycle is determined.  Application rates
are normally expressed as the quantity of wastewater applied per cycle.  The
duration of the wetting or application period and the application rate during
each cycle are determined by the method of application used.  Resting or drying
periods following the wetting period are usually necessary to re-establish
aerobic conditions in the soil.  The optimum drying period is a function of
the land application method and is also very site specific.

Buffer Zone Requirements

When a spray irrigation facility is located near populated areas, a buffer
zone is recommended, especially downwind of the sprinkler.  In some cases,
this may involve scheduling the location of application such that the buffer
zone downwind of the application site is a portion of the field.

In other cases, buffer zones from 15 to 60 m wide around the perimeter of the
site have been utilized.  Provincial regulations may require buffer zones in
excess of these.

Land Forming Requirements

Land forming requirements are usually minimal for spray irrigation but are
important in flood irrigation and ridge and furrow irrigation systems.
Formation of basins is usually required for infiltration percolation systems
and surface alterations may be required in overland flow systems to provide
adequate slope and soil surface characteristics.

Underdrainage Effluent Collection

A subsurface drainage system may be required to prevent excessive groundwater
buildup or to intercept the effluent and collect it for further treatment
prior to discharge.

Storage Requirement

Storage of wastewater may be required under one or more of the following
conditions:

1.   Seeding and harvesting the cover crop


                                     169

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 2.    Precipitation  requiring the temporary reduction or cessation of
      application

 3.    Winter weather requiring reduction of winter application rates

 4.    Winter weather requiring cessation of operation

 When  reduction or cessation of operation resulting from winter weather is
 expected, storage requirements should be based on the maximum expected
 freezing period.  Temporary wastewater storage may be necessary during the
 application season  when excessive rainfall prohibits normal application.   The
 size  of the storage basin must be sufficient to contain anticipated precipi-
 tation during the storage period in addition to the wastewater.

 Distribution System Design

 The distribution system consists of facilities for transmission to the site
 and facilities for  application at the site including pumps, distribution mains
 and laterals, flow  control valves and outlets such as sprinklers for spray
 irrigation systems  or gates for flood irrigation.

 Transmission to the site can be by pressure or gravity.  Velocities in the
 transmission main should be between 2.5 and 3 metres per second.  Gravity
 mains should be at  the low end of the range and force mains should be in the
 middle to upper range.  Where velocities are too high, excessive losses occur
 at bends and valves.

 The distribution system is the most complex component of any land application
 facility; its design will not be discussed in this paper.   Irrigation handbooks
 such  as that by Pair^) provide the pertinent hydraulic design information.

 Monitoring Requirements

 A monitoring program may be required to ensure that proper wastewater treat-
ment  is being carried out and that environmental degradation is not occurring.
 Secondly, monitoring of the cover crop may be useful to optimize its growth
 and yield.   Finally, since application of wastewater to land is likely to
 cause some changes in soil characteristics, periodic monitoring of soil
salinity levels, pH and cation exchange capacity should be practiced.

 LABORATORY AND PILOT EXPERIMENTS

Laboratory and/or pilot plant experiments can be useful in investigating  some
of the technical aspects of the application of wastewater  to land.  Although
 considerable information can be obtained from these studies, caution is
advised since the experimental conditions may be somewhat  artificial.   Green-
house germination tests or growth chamber tests and onsite pilot scale studies
 can all be used as part of the predesign activity to assess the practicality
of land treatment for a specific site.
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Germination tests may be useful to detect potentially acute toxicity
resulting from the application of wastewater.  The test is a comparison of
germination of seeds in soil moistened with wastewater to that in soil
moistened with tap water.

Greenhouse experiments are used to assess plant responses to the application
of wastewater.  These experiments may be carried out by comparing plant
growth from wastewater application with that from tap water application.
The plant tissue and soil can be subjected to chemical and physical analyses
after harvesting.

These experiments require facilities for plant growth and analysis, and
several months of laboratory or greenhouse experimental time.

Onsite pilot studies can provide valuable design data (wastewater application
rates and soil capacities), particularly where the topography and soil type do
not clearly favour one category of application over another.

Pilot studies should be conducted on representative plots, approximately 0.5
hectare in area.  Flat plots may be defined by plowing a furrow around the
perimeter and mounding the soil around the edges.  Sloping plots suitable for
overland flow systems will require a cleared ditch with a flow-measuring
device (Parshall flume or V-notch weir) at the base of the slope.  A network
of wellpoint piezometers should be installed in and around flat areas and
those sloping areas with high permeability to monitor changes in water table
and groundwater quality.

CONCLUSION

For most land application systems, a wide range of design possibilities is
available to suit specific site characteristics, climate, treatment require-
ments, and project objectives.  In addition, a wide range of design possibil-
ities is available for each site.  The designer must rely on a comprehensive
understanding of the treatment principles involved, site evaluation by
specialists and his own ingenuity.  When proper attention is given to the
design of such facilities, land application systems hold a great deal of
potential for the treatment of effluents from food processing plants since
these wastewaters are generally non-toxic and easily biodegradable.
ACKNOWLEDGELMENTS

The material presented in this paper was prepared under a Department of Supplies
and Services Contract (No. OSS76-00225) for the Abatement and Compliance Branch,
Water Pollution Control Directorate, Fisheries and Environment Canada, Ottawa.
The authors also acknowledge the cooperation of the food-processing industries
that contributed valuable operational data for preparation of the design manual
from which this paper has been abstracted.
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LIST OF REFERENCES

1.   Powell, G.M., 1975.  Design factors - Part II.  Prepared for the design
     seminar for land treatment of municipal wastewater effluents, US EPA
     Technology Transfer, New York City.

2.   Jewell, W.J., R.C. Loehr, J.D. Novak, E.L. Stone.  Role of vegetative
     cover In: Education Related to the Land Disposal of Wastes.  EPA
     Project T-900500, Washington, D.C., August 1976.

3.   Ayers, R.S., 1973.  Water quality criteria for agriculture.  UC -
     Committee of Consultants.  CWRCB.

4.   Pair, C.H. (Ed.), 1969.  Sprinkler irrigation.  3rd Edition, Sprinkler
     Irrigation Association, Washington, D.C.

5.   Stanley Associates Engineering Ltd., 1976.  Design and operations manual -
     land application of food processing wastewater.  Prepared for the
     Abatement and Compliance Branch, Food and Allied Industries, Environmental
     Protection Service, Ottawa.
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         USING MICROWAVES TO REDUCE POLLUTION FROM SCALDING CHICKENS

                                     by

         B. F. Miller*,  S. A. Kula*, J. W. Goble**, and H. L. Enos*
The traditional method of achieving feather release of poultry in the slaugh-
tering process is by scalding, which consists of applying moist heat to the
skin to reduce the force required to pull the feathers.  It is usually accom-
plished by immersing birds in or spraying them with water at temperatures
ranging from 54°C for broiler chickens up to 60°C for fowl and turkeys.  The
objective is to loosen the feathers to permit their removal by mechanical
pickers.

Research by Gwin(l) (2) (3) indicated marked advantages for scalding in
reducing labor costs of pinning and in assuring a completely feather-free
bird.  Pool et al.(4) investigated the effects on feather release when live
birds were injected with reserpine.  The force required to pull the feathers
from the treated birds was impressively reduced after 18 hours, but the pre-
injection force required returned almost immediately after the birds' death.
Other methods were also studied, including the effects of radiant heat, brain
sticking, and administration of sodium barbitol.  Klose(5) suggested that
aesthetic and product safety considerations encourage the replacement of
immersion-type scalding; however, the development of commercially feasible
alternatives has been hampered by economic and engineering problems.  Alter-
natives that have been considered include spray or steam scalding and a
combination of the two.

The major limitations of the scalding method are:  (a) the large quantity of
water required (about one quart per bird); (b) the amount of energy necessary
to heat the water (about 200 BTU's per bird); and, (c) the process involved
in disposing of the polluted water that results.

Increasing attention has been directed to these limitations because of rapid-
ly escalating costs of energy, the increasing scarcity of potable water,
societal concerns for environmental quality, and consumer interest in product
quality.   Thus, a need exists to find an alternative system that avoids the
shortcomings of the scalding method for achieving feather release.  After
Miller(6) used a home microwave unit, he concluded that the method might be
feasible to achieve feather release but the results were inconsistent.

The purpose of this study was to investigate further whether exposure of
broilers  to microwave energy would release feathers satisfactorily from the
different feather tracts and whether, as a consequence, underlying tissue
would be adversely affected.
 *Department of Animal Sciences, Colorado State University, Fort Collins,
  Colorado 80523
**Agricultural Research Service, U.S. Department of Agriculture, Beltsville,
  Maryland 20705

                                     173

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PROCEDURE

Broiler chickens ranging in age from 8 to 12 weeks were used in this experi-
ment.  Of the 242 broilers used, 233 were treated with microwave energy.
They were assigned a random number from 1 to 20, representing predetermined
exposure -times.  The nine remaining birds served as controls:  five of them
were scalded by immersion in hot water and four were untreated.

The control group treated by scalding was immersed in water at a temperature
of 61°C for about 1.5 to 2.0 minutes.  Then an incision was made in the
feather tract, and a thermometer was inserted to measure the tissue tempera-
ture.  The force necessary to pull the feathers as a consequence of scalding
was measured with a Dyne-Newton scale equipped with a clamp on the end of a
rod that was attached to a feather or group of them.  As the bird was pulled
manually away from the scale at a uniform rate, the scale moved a relatively
friction-free pin around the dial.  When the feather was released, the dial
needle that indicated the force quickly returned to zero, leaving the fric-
tionless pin stationary at the point of maximum force.

From the data on the control group of birds treated by scalding, the maximum
force acceptable to achieve feather release was determined to be 3.5 Newtons.
This measurement was used as an evaluative criterion for the effectiveness
of microwave treatment.

The birds treated by microwave energy were placed in a commercially available
unit that had a 0.9-meter cubicle chamber containing a carousel-type mode
stirrer to provide uniform exposure.  The unit also contained a power meter
to register the amount of energy that entered the chamber at any given time.

The birds were exposed individually by suspending them by the feet from a
plastic shackle in the microwave chamber.  Each one was subjected to micro-
waves for the specified assigned time at a fixed power level for its respec-
tive treatment group.  The power levels selected were 500, 1500 and 2000
watts.  Exposure times ranged from .25 to 2.0 minutes at .25-minute intervals.

Upon completion of the microwave treatment, the temperature of the tissue and
the pulling force required to remove the feathers were determined for each
bird by the same procedure that was used for the scalded control birds.  The
feather release force was measured for each of the feather tracts (e.g.,
humeral, alar, ventral, spinal, femoral, crural, and caudal).  Tissue damage
was determined by a visual examination of underlying tissue after exposure.

A discriminate analysis was statistically performed to distinguish between
feather release versus non-release and tissue damage versus no damage.

RESULTS AND DISCUSSION

After the first 20 birds were exposed to microwaves, it was found that the
power necessary to achieve satisfactory feather release from femoral, spinal,
and ventral tracts caused extensive tissue damage to the alar, caudal,
crural, and humeral feather tracts.  These findings suggested that the
feather tracts required different levels of power and times for satisfactory

                                     174

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feather release.  A second group of 20 birds was similarly treated to provide
sufficient data for statistical analyses.  The Student t test was used to
statistically analyze the data for each feather tract.  The alar, caudal,
crural, and humeral feather tracts evidenced no significant differences in
the time or power level necessary for feather release without tissue damage.
Similarly, it was found that the femoral, spinal, and ventral feather tracts
had the same relative time and power requirements among themselves.  The find-
ings necessitated that the feather tracts be considered as two separate
groups; one consisting of the alar, caudal, crural, and humeral (extremities)
and the second consisting of the femoral, spinal, and ventral (torso).

The number of power levels originally planned also had to be reduced,  Only
the 1500- and 2000-watt levels were used for the remaining 193 birds because
the 500-watt level was found to be ineffective, and the 2500-watt level was
unattainable with the particular microwave machine that was used.  The orig-
inal exposure evaluation techniques were also modified to make judgmental
decisions about feather release effectiveness and tissue damage resulting
from microwave exposure.  These decisions were made by comparing the effort
required to pick feathers from each bird before and after exposure.  Question-
able results were verified with the Dyne-Newton scale.  Visual examination
for determination of tissue damage was continued.

The results from microwave exposure were classified into four treatment cate-
gories:  Treatment 1 - the femoral, spinal, and ventral feather tracts
exposed to 2000 watts of power; Treatment 2 - the alar, caudal, crural, and
humeral feather tracts exposed to 1500 watts; Treatment 3 - the alar, caudal,
crural, and humeral feather tracts exposed to 2000 watts; and Treatment 4 -
the femoral, spinal, and ventral feather tracts exposed to 1500 watts.

The treated birds were further classified into three groups by discriminate
analysis (Table 1):  Group 1 - underexposed, with no feather release or
tissue damage; Group 2 - optimum exposure, with feather release and no tissue
damage; and Group 3 - overexposed, with feather release and tissue damage.

The findings indicated that satisfactory feather release can be obtained by
exposing a bird to a predetermined level of microwave energy for a predeter-
mined time.  However, the alar, caudal, crural, and humeral feather tracts
must be exposed for less time than the femoral, spinal, and ventral feather
tracts.  The problem is that the microwave unit cannot properly distribute
the energy over a bird's body due to the unequal mass distribution of the
bird.  Theoretically, exposing the torso for a predetermined amount of time
while shielding the extremities to prevent them from being cooked, then sub-
sequently exposing the entire body to the microwave level necessary to release
feathers from the extremities would be ideal.  Such a procedure would permit
all of the feathers to be released without any tissue damage.

From the data generated, equations were developed through discriminate analy-
sis whereby, if a bird's weight is known, the time exposure to microwaves
that would be necessary to achieve feather release at a constant power for
each of the two groupings of feather tracts can be calculated.
                                     175

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                             TABLE  1.   SUMMARY OF MICROWAVE EXPOSURE DATA ON CHICKENS
ON
Feather
Treatment Tract
No. Group*
1 1


Total or Avg+
2 2


Total or Avg+
3 2


Total or Avg"1"
4 1


Total or Avg4"
Total
Birds
No.
14
23
18
55
20
18
22
60
18
19
20
57
4
6
11
21
Weight per Bird


Kg
2.22
2.13
1.95
2.09
2.32
2.27
2.18
2.22
2.18
2.38
2.18
2.27
2.22
2.18
2.09
2.13

Std
Dev
0.59
0.50
0.57
0.58
0.53
0.62
0.52
0.56
0.82
0.57
0.61
0.70
0.72
0.30
0.22
0.37
Microwave
Power
(Watts)
2000
do.
do.

1500
do.
do.

2000
do.
do.

1500
do.
do.

Exposure Time (Min)


Avg
0.58
0.70
0.90
0.74
0.37
0.53
0.77
0.58
0.29
0.47
0.60
0.46
0.50
0.93
1.20
0.99

Std
Dev
0.08
0.13
0.20
0.19
0.09
0.09
0.16
0.21
0.05
0.06
0.15
0.16
0.00
0.24
0.28
0.36


Exposure Results
Underexposed
Optimum exposure
Overexposed

Underexposed
Optimum exposure
Overexposed

Underexposed
Optimum exposure
Overexposed

Underexposed
Optimum exposure
Overexposed

     *1 = Torso
      2 = Extremity feather tracts

     ~*"Weighted averages

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It should be possible to get complete feather release with optimum exposure.
However, some of the experimental birds of relatively equal weight that were
subjected to the same treatment evidenced tissue damage, but comparable birds
did not.  Presumably the tissue damage resulted from differences in tissue
water content.  For example, birds with symptoms of breast blisters before
exposure showed tissue damage in that area after exposure.

The results of this experiment indicated the feasibility of using microwave
energy as a revolutionary approach to achieving feather release from chickens.
Commercial application of the process might be accomplished by either:
(a) weighing the birds before exposure and then subjecting different areas of
the body to microwaves in accordance with the relationship of the weight to
the proper time interval at a predetermined level of energy; or (b) predeter-
mining the microwave exposure time, then weighing each bird and determining
the energy level necessary for optimum exposure, thus allowing a processing
unit to proceed at normal line speed.  Either approach would likely require
the use of a minicomputer on the line to make the determinations.

The potential energy saving from the microwave energy system over the tradi-
tional scalding system is substantial because microwave exposure would require
only an estimated 132 BTU's per bird, whereas heating the one quart of water
that is commonly used per bird would require about 200 BTU's.  In addition,
the use of microwave energy would reduce problems associated with disposal of
the polluted water that results from the scalding process.

Our challenge is to develop equipment that will make the use of microwave
energy economically feasible in commercial processing operations.
                                 REFERENCES
1.  Gwin, J. N.  The sub-scald method of dressing poultry.  American Egg and
    Poultry Review 11(11):8, 10 (1950).

2.  Gwin, J. N.  A report of progress on the scalding method of dressing
    poultry.  American Egg and Poultry Review 12(10):14, 73 (1951).

3.  Gwin, J. N.  The weight and quality of freshly dressed poultry as affect-
    ed by dressing, cooling, and holding.  American Egg and Poultry Review
    12(2):38, 40 (1951).

4.  Pool, M. F., Klose, A. A., and Mecchi, E. P.  Observations on factors
    influencing feather release.  Poultry Sci. 40:1029-1036 (1961).

5.  Klose, A. A.  Poultry Scalding:  Present Technology and Alternative
    Methods.  Proceedings & Abstracts, XV World's Poultry Congress p. 541-
    542 (1974).

6.  Miller, B. F.  Unpublished data.  Dept. of Animal Sciences, Colorado
    State University, Fort Collins (1973).

                                    177

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                    ACTIVATED  SLUDGE  TREATMENT  OF WASTEWATERS
                        FROM THE DAIRY  PRODUCTS INDUSTRY

                                       by

                    P.H.M. Guo*,  P.J. Fowlie*,  and B.E. Jank*
 INTRODUCTION
Regulations and  guidelines  for  controlling  the liquid waste from the Canadian
dairy  industry are  currently being developed by Fisheries and Environment
Canada.   In conjunction with the  task force activity to identify the best
practicable technology  (BPT) for  the treatment of dairy wastes, the Wastewater
Technology Centre,  Burlington,  Ontario undertook a comprehensive sampling and
monitoring program  at three extended aeration activated sludge systems located
at dairy  plants  in  Southern Ontario.  These systems were selected because they
were considered  to  represent BPT  or had  the potential to be upgraded to re-
present BPT.

The program was  carried out in  June, July and part of August, 1977.  These
months represent the annual peak  production period of the Canadian dairy
industry.

Plant A produced ice cream, butter, powdered milk and ice products such as
popsicles and flavoured ice.  The major  products of plants B and C were butter
and powdered milk.  Cheddar and Colby cheeses were also produced at plant B,
however, whey generated from a  cheese making operation was separated and sold
as an animal feed supplement.

The specific objective of the program was to determine whether extended aerat-
ion activated sludge processes  represented  BPT for the treatment of dairy
wastes and to provide a data base to be  used in the development of regulations
limiting the discharge of deleterious substances to the environment.

THE WASTEWATER TREATMENT SYSTEMS

Plant A

The wastewater from this plant was collected in four catch basins,each equip-
ped with bar screens with openings of 2  cm.   The wastewater was pumped to a
30 m3 holding tank and flowed by gravity to a 675 m3 oxidation ditch as shown
in Figure 1.   Aeration and mixing were provided by two cage rotors driven by
a 15 and a 19 kW motor, respectively.   Mixed liquor flowed by gravity to a
* Wastewater Technology Centre, Fisheries and Environment Canada, Burlington,
  Ontario, Canada

                                     178

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    PLANT A
                                  RETURN SLUDGE
       SLUDGE STORAGE
           BASIN
                                OXIDATION DITCH
       HOLDING TANK
                   SLUDGE
                   STORAGE
                   TANK
PILOT-SCALE
 CLAHIFIER
            SAMPLING
INFLUENT /   FLOW
        EQUALIZATION
           TANK   I pUMp
                               AERATION TANK
           PILOT
           SCALE
           CLARIFIER
     PLANT C
                                 RETURN SLUDGE
                                                      CO
                                                      UJ
  INFLUENT
                                  -AERATOR
                                                        UJ
                                                        CO
                                                              EFFLUENT
          HOLDING TANK
                           OXDATKDN DITCH
               FIGURE 1. SCHEMATIC OF TREATMENT SYSTEMS
                                   179

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                                                                  ^
 4.9  m diameter peripheral  feed clarifier,  having a  volume  of  89 m .  Neither
 scum removing  nor sludge  scraping facilities were  provided.   The clarifier
 effluent was  pumped to  the municipal  sewer system.

 Before the  study was initiated,  settled sludge was  returned to the oxidation
 ditch intermittently by a  1.8  m /min  centrifugal pump which was set  to operate
 15 seconds  every four minutes.   Because of the hydraulic surges in the clari-
 fier,   this was changed to continuous operation  at  approximately  0.14 m3/min.
 This  mode of  operation,  providing  a sludge recycle  ratio of 1.2:1, was follow-
 ed for the  duration of  the study.

 Excess sludge was  stored in a  675  m3  sludge storage basin  (Figure 1) during
 the winter  months.   During the summer operation,  excess sludge was pumped from
 the  clarifier and  sprayed  on a field  adjacent to the treatment system.  As
 sludge was  not being stored in the basin at the  time of the study, it was used
 to equalize the flow to  the treatment system.

 Plant  B

 Wastewaters requiring treatment  were  collected in a catch  basin equipped with
 a 0.5  cm screen for separation of  floating materials.  The waste  was pumped
 to a  225  m3 flow equalization  tank which was aerated by air diffusers.  From
 the equalization tank,  the waste was  pumped at a constant  rate to the aeration
 tank.   The  aeration tank having  a  capacity of 300 m3, was  the  outer  compart-
 ment of a 12.5  m diameter  circular tank.   The center compartment  having a
 capacity  of 68  m3 was used as  a  clarifier.  A schematic diagram of the treat-
 ment plant  is  presented  in Figure  1.

 Aeration  and  mixing in  the aeration cell were provided by  diffused air which
 was supplied  by three 15 kW compressors  located  in  a building  adjacent to the
 treatment system.

 Mixed  liquor  flowed by  gravity to  the 4.6  m by 4.6  m clarifier which was
 equipped with  four  sludge  hoppers  on  the bottom.  Settled  sludge  was recycled
 to the  aeration tank by  four air-lift pumps, one  in each sludge hopper.  In
 the original  design,  100 mm diameter  pipes  were  used in the air-lift pumps
 providing a return  sludge  flow approximately 600% of the plant influent.
 Shortly before  the  program was initiated,  two of  the pipes were reduced to
 50 mm  in  diameter and the  other  two were replaced by 38 mm diameter pipes.
 These modifications  decreased  the  return sludge  rate from  600  to  200% of the
 plant  influent.

 The clarifier was equipped with  a  scum baffle at  its perimeter to prevent
 floating solids from discharging with the  effluent.  The floating solids
were collected in a  pipe with a  flared opening located at  the  center of the
 clarifier.  An air-lift pump delivered the  floating solids thus collected to
 the aeration tank.    Effluent from  the  clarifier  flowed by  gravity to a creek.
 Excess sludge was sprayed  as necessary on  a field adjacent to  the treatment
 system.
                                      180

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Plant C

The design of the treatment system at plant C was similar to that of plant A.
The wastewater was pumped from a catch basin in the dairy plant to a 23 m3
holding tank and then flowed by gravity to the 495 m3 oxidation ditch as
shown in Figure 1.  Aeration and mixing were provided by a cage rotor driven
by a 19 kW electric motor.

Mixed liquor flowed by gravity to a 4.3 m diameter peripheral feed clarifier
with the surface area and volume being 14.5 m  and 58.5 m , respectively.
Neither scum removal nor sludge scraping equipment was provided in the clarif-
ier.  Settled sludge was returned to the ditch by a 0.45 m3/min pump which
was operated by a timer to control the sludge recycle ratio at 40 to 250% of
the plant influent.  The excess sludge was sprayed on the field adjacent to
the treatment system.  The clarifier was housed in a building to prevent
freezing in winter. The effluent from this plant was discharged to a river.

Pilot-Scale Clarifier

It was originally identified that there were solid-liquid separation problems
with the clarifiers at plants A and B.  Two pilot-scale clarifiers were in-
stalled and operated in parallel with the existing full-scale clarifiers.
The pilot-scale clarifiers had an 80 cm diameter  and a settling volume of
0.6 m3.   They were fed with the mixed liquor from the aeration basin at a
constant flow rate.  Settled sludge from both pilot-scale clarifiers was pump-
ed to the aeration cells at 50-80% of the feed rate.  Although sludge scraping
mechanisms were provided in both clarifiers, they were not equipped with scum
removal facilities.

MATERIALS AND METHODS

Monitoring Program

1.   Collection four days per week of flow-proportioned, refrigerated, 24-hour
     composite samples of plant influent and effluent.  These were analyzed for
     the biochemical oxygen demand (BOD5), suspended solids and pH;

2.   Twice weekly collection of effluent samples for fish toxicity (Samples
     were collected from the pilot-scale clarifiers at plants A and B and
     from the full-scale clarifier at plant C);

3.   Daily measurement of temperature, dissolved oxygen, suspended solids and
     pH of the mixed liquor;  and

4.   Continuous measurement and recording of the flow rate to the treatment
     system.

Bioassay Testing

Static with replacement bioassays were carried out in the study.  The undilut-
ed effluent sample was cooled to 15°C and then sub-divided into four, 40-liter
samples each held in polyethylene containers lined with disposable food and

                                     181

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 drug approved polyethylene bags.   Ten  juvenile rainbow trout  (Salmo
 gairdneri)  weighing between 1.5-2.0 g and averaging 4 to 5 cm  in length  were
 placed in one of the 40-liter samples for the first 24 hours,  then trans-
 ferred to the second,  third and fourth containers after 24,  48 and 72  hours,
 respectively.  Renewing the solutions every 24 hours provided  an effluent
 volume to fish weight  ratio of 2  £/g-d.   Dissolved oxygen concentrations in
 the  effluent  were maintained above 7.0 mg/£ by aerating the  test solutions at
 5  mi/X-'min.   Solutions not containing fish were not aerated  until a few  hours
 prior to  transferring  the  fish.

 WASTEWATER  FLOW AND CHARACTERISTICS

 The  flow  rate and characteristics of  wastes generated from each dairy  plant
 were  different,  depending  on the  quantity of milk and type of  products being
 processed.  The degree of  in-plant management exercised at each plant  to
 reduce the waste load  accounted for the difference in the quantity and quality
 of the waste.   A discussion of the flow rate and characteristics of wastes
 from  each dairy plant  is presented in the following sections.

 Wastewater  Flow

 The flow  rate to the treatment system at  plant A ranged from 59 to 255 m3/d
 (Figure 2).   During the first  week of the study,  no effort was made to control
 the flow  to the  treatment  system  and  the  daily flow rate  fluctuated signifi-
 cantly.   In the  second week, part of  the  waste was diverted  to the spraying
 field  to  reduce  the hydraulic  loading to  the clarifier.   Starting June 17, the
waste  from  the  dairy plant  was stored in  the sludge storage  basin and  a  sub-
mersible  pump delivered the waste at  a constant rate to the  oxidation  ditch.

Approximately one week later,  odour problems were encountered  in the basin.
Consequently,  the daily flow rate to  the  treatment system was  gradually
increased in  an  attempt to  empty  the  basin.   At the same  time,  efforts were
made to provide  aeration and mixing to control the odour  problems.  During the
period  from June  17 to July 8,  although the total flow to the  treatment  system
changed from  day  to day, the flow rate was  kept constant  during individual
days.   On July  8, the  basin was completely  emptied and  thoroughly cleaned.
After July 8,  the treatment  system was operated at a flow 'rate which was
approximately equal to the  total  daily flow from the dairy plant.   This mode
of operation  allowed the sludge storage basin used for  flow  equalization to
be emptied daily  and prevented  the  septic condition from  occurring in  the
basin.

Daily flow rate  to  the treatment  system at  plant  B varied from 14 to 203 m3/d
with the average  being 113  m3/d (Figure 2).   Daily adjustment  of  the flow rate
was necessary in  order to accommodate  the flow variation  coming from the dairy
plant, however,  the flow rate  to  the  treatment  system was  kept  constant during
the individual days.

To promote mixing and  oxygen transfer, the water  depth  in  the  flow equal-
ization tank was maintained  at greater than  0.6 m at  all  times.   On June 28,
the tank was emptied for cleaning.  The discharge  of  the  daily  waste flow
                                      182

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       7  8 9 K> 14 15 16 17 21 22 23 24 28 28 30 5 6 7 8 12 13 14 15 19 20 21 22 26 27 28 29 3 4 5  9 K) 11 12

                  JUNE.1977                    JULY.1977           AUGUST.1977
CC
                                                  PLANT B
       7  8 9 10 14 IS 16 17 21 22 23 24 28 29 30 5 6 7 8 12 13 W 15 19 20 21 22 26 27 28 29 3 4 5  9 10 11 12
                JUNE. 1977
                                            JULY, 1977
AUGUST, 1977
 FIGURE 2. DAILY WASTE FLOWS TO THE  TREATMENT SYSTEMS AT
            PLANTS A AND B
               I "T  T  T  T~T~ i—i—i—i  T i—'  T  i—i—i—i—i—I—i—i  T  I—r
             7 8  9  10  14  15 16 17 21 22 23 24 28 29 30  5  6 7 8  12 13 14  15  19 20 21 22 26 27 28 29

                       JUNE,1977                     JULY, 1977


       FIGURE 3. DAILY WASTE FLOWS TO THE TREATMENT SYSTEM  AT PLANT C
                                     183

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 plus  the content of the flow equalization tank resulted  in a maximum  daily
 flow  rate of  203 m3/d  to the treatment  system.   The minimum flow rate occurred
 on the  following day,  because part of the waste was stored in the flow equal-
 ization tank  to maintain the 0.6 m minimum liquid  level  necessary for aeration.

 The daily average flow rate  to the treatment  system at plant C is shown in
 Figure  3.   The  maximum and minimum flow rates for  the individual days are also
 presented.  As  can be  seen from the figure, the flow rate  fluctuated  from day
 to day  as well  as throughout the individual days.   While the daily maximum
 flow  rate measured was 295 m /d the minimum flow rate was  close to zero on a
 number  of occasions.

 Wastewater Characteristics

 BODs  and Suspended Solids

 The daily variation in the BODs and suspended solids concentrations for the
 wastes  from plants A,  B and  C is presented in Figure 4.  Two abnormal peaks in
 the concentration of both BODs and suspended  solids were measured at  plant A.
 The first peak  occurred during the period from June 9 to 14,  when the holding
 tank  was being  cleaned.  The second peak occurred  on July  8,  corresponding to
 the day  the sludge storage pond was emptied and cleaned.   On both occasions,
 wastes with high milk  solids were discharged  to the treatment system,  result-
 ing in a great  increase in the BODs an
-------
        *      PLANT A
                 '••   A. ^  A   a
                  W   -^v  V-'
                                      'X    *   /   \
     7 8 9 1)14151617212223242820305 6 7  81213141S19202122262728293 4  5 9 » 11 12
             JUNE.1977                    JULX1977           AUGUST.1977
    7 8 010M1Siei7212223242a2S305 6 7 8 1213U151&2021222728293 4 5 9 10 11 12
          JUNE.1977               JUX1977                AUC3UST.1977
             PLANT C
    7 8 9  10 14 15 16 17 21 22 23 24 28 29 30 5  6 7 8 12 13 14 15 19 20 21 22 26 27 28 29
             JUNE, 1977                   JULY, 1977
FIGURE 4. DALY INFLUENT  BOD5 AND SUSPENDED SOLIDS
          CONCENTRATIONS
                               185

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             TABLE 1.   SUMMARY OF  INFLUENT WASTEWATER CHARACTERISTICS
Parameters Minimum Maximum
A B C ABC
Average
ABC
BOD5
(mg/£)   1700   840   380    6000  3800   1900     2850    1960
950
 Suspended
   Solids  (mg/a)   350    300    610    5190   2460  2500    1290    1120   1240
PH
         3.8   4.4    7.2    10.1  10.9   12.0
The pH of  the untreated waste was also highly variable for all  the plants.
The major  factor affecting  the pH was the  type and quantity of  sanitizers and
cleaning agents used in the dairy plant.   As shown in Table 1,  the pH of the
wastes from plants A and B  had a greater degree of variation than that from
plant C.   At plant C, the waste had a significantly higher pH value than that
from the other two plants,  indicating the  difference in the use of sanitizers
and cleaning agents at this plant.

OPERATING  PARAMETERS OF TREATMENT SYSTEMS

The average operating parameters for the three treatment systems are shown in
Table 2.   Based on the organic loadings, it could be seen that all three
systems were operated as an extended aeration activated sludge process.  The
day to day fluctuation in the mixed liquor suspended solids for the three
treatment  systems is presented in Figure 5.  A significant increase in MLSS
concentration occurred in the oxidation ditch at plant A on July 8, when the
storage basin was emptied.  This was caused by the discharge of a high con-
centration of milk solids into the treatment system.  Although efforts were
made to control the solids  concentration by sludge wasting on the following
days, it was impossible to  reduce the concentration to its original level due
to the limited capacity of  the sludge wasting facilities.  A steady decrease
in the MLSS concentration did not occur until July 22;  two weeks after the
increase in the solids concentration.  Apparently, the amount of sludge wasted
during this period was offset by the rapid solids build-up due to microbial
growth and the high influent suspended solids concentration.

The dissolved oxygen level  in the oxidation ditch at plant A was generally
maintained above 2 mg/Ji.   The discharge of the high concentration of milk
solids resulted in a drop of dissolved oxygen concentration to less than 0.5
mg/£ during the period from July 8 to 13.  Low dissolved oxygen levels
measured on July 5 and 29 were caused by a malfunction of one surface aerator.
                                     186

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00
          CO

          O
              8000-
              6000-
             4000 H
              2000-
jfj  6000H
O

O  5000-
o

VI  4000-
             6000-



             5000-


             4000-


             3000-
             2000-1—r
                   7
                         PLANT A
                                                                           V
                                                                              V
                     V
                         PLANT B
                               O-o-O
               PLANT C
        /    \
                            y
         **•—+'
             -|—i—r—i—i—i—i—i—i—i—i—i—r
             10 14 15 16 17 21 22 23 24 28 29 30 5
~i—i—i—i—i—i—i—i—i—i—i—^—>—r
 8 12 13 14  15 19 2021 22 2627 28 29 3
~I—I	1—T
5 9  10  11 12
                            JUNE,1977
                                           JULY, 1977
                        AUGUST, 197 7
                  FIGURE 5. MIXED LIQUOR SUSPENDED SOLIDS CONCENTRATIONS

-------
The MLSS concentration in the aeration tank at plant B was maintained between
3900 and 6600 mg/£  (Figure 5).  Although the three compressors were operated
at full capacity, 50% of the time, the dissolved oxygen level in the aeration
tank was less than  1 mg/£ and 75% of the time, it was lower than 2 mg/£.  Dis-
solved oxygen concentrations less than 0.5 mg/£ were measured on several
occasions and these were related to compressor breakdowns.  There was no spare
unit available to provide reserve aeration capacity for emergencies.
                    TABLE 2.  AVERAGE OPERATING PARAMETERS
1. Aeration Tank
Flow Rate (m3/d)
Plant A
142
Plant B
113
Plant C
170
    Organic Loading
    (kg BOD5/kg MLSS-d)

    Detention Time (d)

    MLSS Concentration (mg/£)

2.  Clarifier

    Surface Loading (m3/m2-d)

    Solids Loading (kg/m  *d)

(1)  Full-Scale Clarifier

(2)  Pilot-Scale Clarifier
   0.11

   4.8

5300

 111  .(.?_)..

  10   14

  44   49
   0.14

   2.7

5070

(1)  (2)

 5    14

24    65
   0.08

   2.9

4030



  16

  54
At plant C, the MLSS concentration was generally maintained between 3500 and
4500 mg/£  (Figure 5).  There was sufficient dissolved oxygen in the oxidation
ditch except for two occasions when extremely low concentrations (less than
0.5 mg/£) were measured.  The cause of the low dissolved oxygen reading was
not identified.

Although the influent pH was highly variable as mentioned previously, little
change was observed in the pH of the mixed liquor in the aeration tanks of all
three treatment systems.  It ranged from 6.9 to 7.9 for the mixed liquor of
the treatment systems at plants A and B and from 7.4 to 8.8 for plant C.  The
slightly higher pH value of the mixed liquor at plant C could be related to
the higher influent pH.  As all the mixed liquor pH's were within the optimum
range for microbial growth in a biological treatment system, there was no
requirement for chemical addition for pH adjustment.  It must be concluded
that there was always sufficient mixing and buffering capacity in the aeration
                                     188

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tank to neutralize the waste.

The surface and solids loadings of the full- and pilot-scale clarifiers are
shown in Table 2.  The loadings shown for the pilot-scale clarifiers were
calculated based on a flow rate of 4.6 £/min.

OPERATING RESULTS

Plant A

The daily effluent BODs and suspended solids concentrations for both the
pilot- and full-scale clarifiers are shown in Figure 6 and 7, respectively.
As can be seen from the figures, the pilot-scale clarifier operated at a
constant flow rate produced significantly better quality effluent during the
first month of operation.  After the operational problems in the full-scale
clarifier were rectified by flow equalization, a stable operation was achieved.
Starting July 6, the quality of effluents from both clarifiers was compar-
able.

The deterioration in the effluent quality of the pilot-scale clarifier on
July 13 and 14, could be related to the high solids concentration in the
oxidation ditch caused by the discharge of milk solids.  The significant
increase in the MLSS concentration after July 8, resulted in an increase in
solids loading from 49 to 88 kg/in2- d which was too high for the pilot-scale
clarifier.  The sludge blanket was at the top of the clarifier on both days.
To rectify the problem, the feed rate was reduced from 4.6 to 3.2 il/min on
July 15 which resulted in a reduction of the solids loading from 88 to 63
kg/m2-d and the surface loading from 14 to 10 m3/m2-d.  As a result, the
sludge blanket dropped and good quality effluents were achieved for the rest
of the study.
The average BODs and suspended solids concentrations for effluents from the
pilot-scale clarifier were 12 and 43 mg/£, respectively, which corresponded
to a 99% BODs and 97% suspended solids reduction.  These results were cal-
culated using all the collected data except those on July 13 and 14.

Effluent data from the full-scale clarifier could be divided into two groups.
One group dealt with the data collected prior to July 5, which covered the
first five weeks of operation.  BOD5 and suspended solids concentrations
during this period of operation were extremely high and exhibited a great
degree of fluctuation.  The other group represented the data obtained after
July 6, when the daily waste flow to the treatment system was kept constant.
This group of data collected over a period of approximately six weeks re-
presented the performance of a well designed and properly operated treatment
system and was considered to be representative of the BPT operation.  A
summary of the operating results for this group is shown in Table 3.
                                     189

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                    CHANGE TO CONSTANT FLOW
                                               *— FULL-SCALE CLARFIER
                                               .— PILOT-SCALE CLARIFIER
    n—i—i—r—i—r—i—i—i—i—f—f—i—i—i—i—i—i—i—i—i—i—i—i—r—i—i—i—i  r
     7  8  9 10 14 15 16 17 21 22 23 24 28 29 30 5  6  7  8 12 13 14 15 18 20 21 22 26 27 28 29 3 4 5 9 10 11 12
             JUNE, 1977
JUNE, 1977
AUGUST, 1977
   FIGURE 6. DAILY EFFLUENT BOD5 CONCENTRATIONS AT PLANT A
                  CHANGE TO CONSTANT FLOW
                                                     FULL-SCALE CLARIFIER
                                                     PILOT-SCALE CLARFIER
                        i—i—l—l—l—l—i—i—i—i—'—i—i—i—i—r—i—i—i—i—i—i—i—r—r
     7 8 B 10 14 16 16 17 21 22 23 24 28 28 30 5  6  7  8 12 '3 14 15 19 20 21 22 26 27 26 29 3  4  5 9 10 11 12
                JUNE, 1977                JULY, 1977               AUGUST, 1977

FIGURE 7. DAILY EFFLUENT SUSPENDED SOLIDS CONCENTRATIONS AT PLANT A
                                  190

-------
               TABLE 3.  SUMMARY OF EFFLUENT RESULTS - PLANT A,
                         FULL-SCALE CLARIFIER*
Parameters
BOD5 (mgA)
Suspended Solids (mg/£)
Minimum
7
12
Maximum
29
109
Average
13
32
% Reduction
99
98
   *  Data collected from July 6 to August 12, 1977
From the data presented, it can be seen that the performance of the treatment
system was significantly improved by flow equalization.  Before June 17, the
sludge blanket in the clarifier was visible at all times and on several
occasions it reached the water surface resulting in severe loss of sludge over
the weir of the clarifier.  Starting June 17, when the sludge storage basin
was used to equalize the flow, the sludge blanket gradually dropped in the
clarifier.  Approximately one week later, the sludge blanket was no longer
visible.

During the operating period from June 24 to July 7, scum was observed in both
clarifiers.  The scum was formed in the oxidation ditch and was carried over
to the clarifier with the mixed liquor.  As neither the full-scale nor the
pilot-scale clarifier was equipped with scum removal facilities, the solids
were carried away with the effluent resulting in a high suspended solids con-
centration in effluents from both clarifiers (Figure 7).  However, the BODs
results were only slightly affected by the scum in the sample as shown in
Figure 6.  This indicated that most solids in the scum were inert and did not
exert an oxygen demand.

A malfunction of the effluent pump caused by power failure on June 30, resulted
in a rise of the water level and sludge blanket in the full-scale clarifier.
The high sludge blanket, in addition to the scum problem mentioned earlier,
could have been partially responsible for the high effluent BODs and suspended
solids concentrations measured.

After July 6, stable operation of the treatment system was achieved.  The dis-
charge of 210 m3 of highly concentrated wastes to the oxidation ditch on July
8, appeared to have no affect on the performance of the treatment system.

As indicated before, aqueous ammonia was added to the waste as a supplemental
nitrogen source.  During the first two weeks of operation, ammonia was added
at 200 mg/ji in terms of nitrogen.  This dosage was based on an estimated
influent EOD^ concentration of 4000 mg/£.  As excessive ammonia concentrations
in the effluent samples were detected, the dosage was reduced to 114 mg/£ on
June 16.  Although the effluent ammonia concentration started to decrease, a
steady increase in the nitrite concentration was observed in effluents from

                                      191

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both clarifiers.  Apparently the ammonia dosage was  still  too high and  the
decrease in the effluent ammonia concentration after the reduced dosage was
partially attributed to nitrification occurring in the system.  On July 4,
the ammonia dosage was reduced again to 58 mg/£.  Two days later, a steady
decrease in the nitrite concentration was measured in the  effluent.  After
July 13, both the ammonia and nitrite concentrations in the effluent were
consistently less than 1 mg/£ expressed as nitrogen.

During the period when high nitrite concentrations were measured in the
effluent, no nitrate was detectable, indicating that nitrification was  not
complete.  The cause of this phenomenon was not investigated during the study.

Plant B

The daily BODs concentration of effluents from both  the full- and pilot-scale
clarifiers is shown in Figure 8.  The effluent suspended solids data are
presented in Figure 9.  As can be seen from Figure 8, the.  BODs results  from
both clarifiers were comparable.  The discharge of a highly concentrated
waste, combined with the extremely high flow rate on June  28, detrimentally
affected the performance of the treatment system.  A substantial increase in
the population of filamentous micro-organisms was observed in the sludge
floe and the sludge blanket in both clarifiers reached the water surface
during the period from June 28 to July 6.  The continuous  loss of sludge over
the clarifiers resulted in a deterioration of the effluent quality as shown
in Figures 8 and 9.

Scum, similar to that occurring in the treatment system at plant A, was
frequently observed in both clarifiers.  As the full-scale clarifier was
equipped with baffle and skimming devices, the scum, if not too excessive,
could be prevented from discharging with the effluent.  However, such facili-
ties were not available in the pilot-scale clarifier.  As a result, effluents
from the; pilot-scale clarifier usually contained higher suspended solids than
those from the full-scale clarifier.

Aside from the period between June 28 and July 6, suspended solids concent-
rations greater than 100 mg/£ were measured in the effluent from the full-
scale clarifier on four occasions.   This was attributed to an excessive scum
accumulation in the clarifier, resulting in partial  discharge of solids with
the effluent.

Rising bubbles and lumps of black sludge were observed in the full-scale
clarifier on several occasions.  As the clarifier was not equipped with
sludge scraping mechanisms, this allowed part of the sludge to adhere to the
bottom of the clarifier.  Prolonged storage of sludge resulted in denitrifi-
cation or the development of septic conditions which caused the sludge  to
rise to the surface.  Because the clarifier was equipped with scum baffle,
the floating sludge was retained in the clarifier and prevented from leaving
with the effluent.  Eventually the floating sludge either sank to the bottom
or was collected by the skimming device and returned to the aeration tank by
an air-lift pump.  This problem was not encountered  in the pilot-scale
clarifier as it was equipped with sludge scraping facilities.


                                     192

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    600-
    500-
    400-
    300-
 O  200-
     100-
                                           —o— FULL-SCALE CLARIFIER
                                                PILOT-SCALE CLARIFIER
          -I—i—i—i—r
         7 8 9 10 14 15 16 17 21 22 23 24 28 29 30 5 6 7 8 12 13 14 15 19 20 21 22 27 28 29 3  4 5 9 10 11 12
                JUNE.1977               JULY, 1977                  AUGUST, 1977

         FIGURE 8. DAILY EFFLUENT BOD5 CONCENTRATIONS AT PLANT B
O)
O
 3000-


 2000-


 1000-
'    >
 400-




 300-




 200-




 100-
                             *5800
                                           o—FULL-SCALE CLARIFIER
                                           •--PILOT-SCALE CLARIFIER
        7 8 9 10 14 15 16 17 21 22 23 24 28 29 30 5 6 7 8 12 13 14 15 19 20 21 22 26 27 28 29 3 4 5 9 10 11 12
              JUNE ,1977               JULY, 1977                    AUGUST, 1977

    FIGURE 9. DAILY EFFLUENT SUSPENDED SOLIDS CONCENTRATIONS
              AT PLANT B
                                    193

-------
 A summary of  the operating results is presented in Table 4.   These results
 were calculated using the data considered to be representative of the BPT
 operation.   The data collected from June 28 to July 6,  when  the system was
 upset due to  the discharge of a concentrated septic waste, were not included.
 The  percent  reduction was calculated using the average  values shown in
 Tables 1 and  4.

 As indicated  in the table, the quality of effluents from the full-scale
 clarifier was slightly better than that from the pilot-scale clarifier.  The
 average effluent BODs concentration for the full-and pilot-scale clarifiers
 was  22 and 25 mg/£,  respectively,  which corresponded to a 99% reduction for
 both clarifiers.   The effluent suspended solids concentration averaged 55
 and  65 mg/& for  the full- and pilot-scale clarifiers, respectively,  which re-
 sulted in a 95 and 94% reduction as shown in the table.
                TABLE  4.   SUMMARY OF  EFFLUENT  RESULTS*  -  PLANT  B
Parameters
Minimum
(1) (2)
Maximum
(1) (2)
Average
(1) (2)
% Reduction
(1) (2)
BOD5   (mg/£)          37         50      63      22      25      99      99

Suspended
   Solids  (ing/A)      9      24        250     368      55      65      95      94

*  Excluding the data collected  from June  28 to July 6.

(1)  From  the full-scale clarifier

(2)  From  the pilot-scale clarifier
Plant C

The plot of effluent BODs and suspended solids concentrations versus date of
operation is shown in Figure 10.  As indicated in the figure, the majority of
effluent BODs and suspended solids concentrations were less than 20 and 50
mg/£,, respectively.  Occasionally, temporary problems with hydraulic surges
were encountered in the clarifier.  On  June 14, 24, 29 and 30, and July 5 and
7, the sludge blanket reached the water surface for periods ranging from 2 to
12 hours, causing loss of solids in the clarifier.  The resultant high BODs
and suspended solids concentrations are encircled and shown as unconnected
points in Figure 10.  On these days, in addition to the usual 24-hour compos-
ite sample, another composite sample was prepared using samples taken during
the hours of normal operation.  Analytical results for these samples are
presented as connected points in the same figure.  The number of hours of
normal operation varied from 12 to 22 hours and has been noted in the figure.


                                      194

-------
Ol
1000 H
        O)
        <
        DC
LLJ
O

§
O
           500-
            100
                                      TT
                                      1598  1793
                                                         —•— ss
                                                           ® )

                                                           ® }
                                                      CAUSED BY

                                                   ®  HYDRAULIC SURGES
                                       "I—I—I—I—I
                   8  9 10 14 15 16 17 21 22 23 24 28 29 30 5
                             JUNE, 1977
                                            ~i—i—i—i—i—i—r~i—i—i—i—i—i—r
                                             7  8 12 13 14  15 19 20 21  22 26 27 28 29

                                                   JULY, 1977
         FIGURE 10. DAILY EFFLUENT  BOD5 AND SUSPENDED SOLIDS CONCENTRATIONS AT
                  PLANT C

-------
 During the week of July 19 to 22, floating sludge was observed in the clarif-
 ier.   The problem could be attributed to nitrification or the development
 of septic conditions in the clarifier as mentioned previously.  The discharge
 of floating solids with the effluent resulted in a deterioration of the
 effluent quality as shown in Figure 10.

 Since the problems with the hydraulic surges were of a temporary nature,  and
 could have been readily rectified by adequate flow equalization, the encircled
 values were considered to be not representative of BPT operation,  and there-
 fore, were not included in the data anlysis.

 A summary of the operating results for the treatment system is presented  in
 Table 5.   The average effluent BODs and  suspended solids  concentrations were
 7 and 28 mg/£,  respectively,  which corresponded to a 99%  BODs  and  98% sus-
 pended solids removal.

 The results from the summer operating period were compared with those from a
 similar sampling program carried out at  this plant in February and March
 1976.   During the  winter program the system was operated at an average
 organic loading of 0.09 kg BODs/kg MLSS-d at a liquid temperature  of approxi-
 mately 8°C.   The results from the 5-week sampling program indicated that  the
 average effluent BOD5 and suspended solids concentrations were 7 and 12 mg/£,
 respectively;   these values represent a  99% removal for both BODs  and suspend-
 ed solids.   These results show that at a similar organic  loading,  performance
 of the treatment system was not affected by a significantly reduced liquid
 temperature.
                 TABLE  5.   SUMMARY  OF  EFFLUENT  RESULTS* -  PLANT  C



Parameters                         Minimum  Maximum   Average   % Reduction

BOD5  (mg/X,)                           2         18          7          99

Suspended Solids  (mg/£)               5         49          28          98

*Excluding the data collected when the clarifier was affected by hydraulic
 surges



BIOASSAY RESULTS

The results of fish bioassays are  shown in Table 6.  As indicated, the major-
ity of the samples were non-acutely lethal to  rainbow trout.  The four samples
which exhibited 100% mortality, were  associated with high ammonia concent-
rations in the effluent.  Ammonia  has been reported to be lethal to rainbow
trout in the un-ionized form (NH3) at 0.2 to 0.5 mg/£ in terms of nitrogen (1).
Analytical results indicated that  the samples  exhibiting 100% fish mortality
contained 0.7 to 2.9 mg/£ of non-ionized ammonia expressed as nitrogen.  The

                                      196

-------
high ammonia  concentration present in the effluent from the treatment system
at plant A was  due  to an  over-dosage of ammonia in the waste as indicated
previously.   No explanation could be provided for the high ammonia concent-
ration in the effluents from the treatment systems at plants B and C.
                          TABLE 6.  BIOASSAY RESULTS

Plant

No. of
Samples
Tested
No. of Samples
Exhibiting No
Mortality

Remarks

  A        15           11          1 sample exhibited 100% mortality
                                    1 sample exhibited  20% mortality
                                    2 samples exhibited 10% mortality

  B        17           15          Both samples exhibited 100% mortality

  C        15           14          100% mortality
As mentioned previously, over-dosage of ammonia during the early weeks of the
study also resulted in a high nitrite concentration in the effluent.  Analy-
tical results indicated that the three samples from plant A exhibiting partial
mortality contained 36 to 96 mg/£ of nitrite-nitrogen which were 150 to 400
times the lethal level of 0.23 mg/£ reported by Brown and McLeay (2).  How-
ever, only 10 to 20% mortality was observed, suggesting that some form of
antagonism was occurring in the sample.  Perrone and Meade (3) reported a
positive interaction between nitrite and chloride.  Subsequent analyses of the
effluents revealed chloride levels of 200 to 500 mg/£.  The antagonistic
relationship was confirmed by exposing rainbow trout to 50 mg/£ of nitrite-
nitrogen with and without 300 mg/£ of chloride.  The samples containing
chloride were non-acutely lethal while samples without chloride resulted in
100% mortality.

OPERATIONAL PROBLEMS AND CORRECTIVE MEASURES

Three major operational problems were encountered at the treatment systems
during the study.  The nature of the problems and their corrective measures
are presented as follows:

Hydraulic Surges

Hydraulic surges to the treatment system caused by washing and cleaning ope-
rations in the dairy plant have resulted in overloading of the clarifiers at
plants A and C.  The hydraulic surges lifted the sludge blanket to the surface
of the clarifier, resulting in a discharge of suspended solids.  The solution
to the problem was to provide a constant flow to the treatment system which
can be accomplished by the use of a flow equalization tank.  This can be

                                     197

-------
provided  through  the construction of new  facilities or through the modifi-
cation  of existing  facilities.  During  the study the sludge storage basin at
plant A was used  for this purpose.  However, it should be noted that the
basin is  not  available for  flow equalization in winter months as it is used
to store  the  excess sludge  from the treatment system.  To ensure a satis-
factory performance year-round, flow equalization is required.

At plant  C, an attempt was  made to determine the feasibility of using the
existing  holding  tank to equalize the flow.  The diurnal flow pattern of the
day having the most variable flow during  the study was selected (Figure 11)
and a hydrograph  was constructed as shown in Figure 12.  The vertical distance
between the two solid lines tangent to  the accumulated flow curve represents
the storage volume required.  This volume was calculated to be 23 m3 which
happened  to be the same as  the volume of  the holding tank on site.  Therefore,
it is feasible to operate the holding tank as a flow equalization tank to pro-
vide a  constant flow to the oxidation ditch.  The only modification required
is to install a pump having the capacity  to handle the average daily flow.
As no reserve capacity is available, occasional overflow could occur due to
unforseen changes in diurnal flow.  The effect of such an overflow on the
treatment system would be less significant than the effect of the unequalized
hydraulic surges  experienced during the study.

The problems with hydraulic surges did not occur at plant B, because a flow
equalization  tank was available at this plant.

Scum

During  the study, the aeration tanks at plants A and B were covered with a
thick scum sometimes to a depth of 0.5 m.  It was called 'scum' rather than
'foam' because it could not be collapsed  by water spraying.  Part of the scum
entered the clarifiers with the mixed liquor, resulting in floating solids in
the clarifiers.  As no scum removal facilities were available at plant A, the
solids were carried over the weir of the  clarifier, producing effluents with
high suspended solids concentration.  The scum in the clarifier at plant B
was retained by the scum baffle and eventually was returned to the aeration
tank by an air-lift pump or removed manually.

The solution  to the problem is to control the scum formation, or failing this,
to remove the scum from the oxidation ditch.  Scum can be prevented from
entering the clarifier with the mixed liquor by a properly designed entrance
facility.   As a final measure, scum baffle and skimming devices should be pro-
vided in the clarifier to keep the scum from discharging with the effluent.

Floating Sludge

Rising bubbles and lumps of black sludge were observed on several occasions,
in each of the full-scale clarifiers.   As none of the clarifiers were equip-
ped with sludge scraping mechanisms, this allowed part of the sludge to
adhere to the bottom of the clarifier.   Prolonged storage of sludge resulted
in denitrification or the development of  septic conditions which caused the
sludge to rise to the surface.


                                     198

-------
    250-




 ^ 200-

 CO

 PO^


 LU

 OC  100-



 ^  50-
      SAM      12
              NOON
            4PM     8PM      12       4AM      SAM
                          MID - NIGHT
                              TIME
 FIGURE 11. THE MOST VARIABLE DIURNAL FLOW PATTERN AT PLANT C
    150-
00
 LU
    100-
 LU
o
    50-
                             TANK IS FULL
STORAGE
CAPACITY
REQUIRED  I
     SAM      12
             NOON
           4PM     8PM      12      4AM      SAM
                          MID-NIGHT

                   TIME
  FIGURE 12. HYDROGRAPH FOR THE DIURNAL FLOW PATTERN
            PRESENTED IN FIGURE 11
                               199

-------
 The solution to the problem is self-evident.   The  provision of  a  sludge
 scraper to facilitate a rapid movement of the  settled  sludge to the hopper
 for recycling or wasting is essential in the design of the  clarifier.  The
 importance of the scum removal facility should not be  overlooked  as it pro-
 vides  a final protection to prevent  the floating solids including scum and
 floating sludge from discharging with the effluent.

 CONCLUSIONS

 Based  on the results from the study,  the following conclusions  can be drawn:

 1.   The extended aeration activated  sludge process  can be  considered to
     represent best practicable technology for the treatment of dairy wastes.

 2.   The three extended aeration activated sludge  systems were  operated at
     organic loadings of 0.11,  0.14 and 0.08 kg BODs/kg MLSS-d, respectively.
     In each case,  99% BODs  reduction was attained.  For suspended solids a
     98% reduction  was achieved at the treatment systems of  plants A and C,
     and 95% at  plant B.   The average effluent concentrations for the three
     treatment systems were  13,  22 and 7 mg/£  for  BODs  and  32,  55 and 28 mg/£
     for suspended  solids.

 3.   Hydraulic surges due to washing  and cleaning  operations  of the dairy
     plant  detrimentally affected the performance  of the treatment systems
     at  plants A and C.   This problem was not  encountered at  plant B, because
     flow equalization facilities were available.  The  use  of the existing
     sludge storage basin for flow equalization at plant A  substantially
     improved  the performance of the  treatment system.

 4.   Occasionally,  floating  sludge due to denitrification or  the  development
     of  septic conditions  in the clarifier was  observed in  the  full-scale
     clarifiers.  Scum formed in the  aeration  cells at  plants A and B was
     carried over to the  clarifiers with the mixed liquor.   The provision of
     scum baffle  and skimming devices  in the clarifier  at plant B prevented
     the  floating sludge  from discharging with the effluent.  The absence of
     such  facilities  in  the  other clarifiers resulted  in a deterioration of
     the  effluent quality.

5.   The majority of  the  effluents from the three  treatment  systems were non-
     acutely lethal  to rainbow  trout.   In cases where  fish mortality was
     observed, it was  identified to be  related  to high  un-ionized ammonia
     concentrations  in the effluent.    Effluents containing high nitrite con-
     centrations were not acutely lethal,  presumably due to  the antagonistic
     interaction between nitrite and  chloride  present  in the  effluents.

DESIGN RECOMMENDATIONS

The results of the  study  indicated that  dairy wastes can be  treated success-
fully in a  properly  designed  and well  operated extended  aeration  activated
sludge system.  To  ensure a  satisfactory  operation at all times,  the system
should consist of the  following components:
                                     200

-------
 1.   Catch basin equipped with  screening devices to remove large floating
     materials.

 2.   Flow equalization  tank to  provide a constant flow to the subsequent
     treatment units.

 3.   Aeration tank to oxidize the organic compounds in the waste.

 4.   Clarifier to separate the  biological solids from the liquid.

 A supplemental nitrogen source  will be required for treating the wastes which
 are deficient in this nutrient.

 Based on the experience gained  at the three systems, the following important
 parameters should be considered in the design of a treatment system.

 For the flow equalization tank, the volume is determined, based on the diurnal
 flow pattern of the waste to be treated.  Aeration and mixing should be pro-
 vided to prevent septic conditions and to avoid deposition of solids in the
 tank..  Design details on this subject are covered in an EPA report entitled
 "Flow Equalization" (4).

 As an alternative, the  use of the aeration tank to dampen the flow and a pump
 to provide a constant flow of mixed liquor to the clarifier may be a cost-
 effective solution for  some treatment systems.  However, the feasibility of
 using this mode of operation is dependent on the degree of flow variation and
 should be investigated  on a case by case basis.

 The aeration tank should be designed at an organic loading of approximately
 0.1 kg BODs/kg MLSS'd.  Sufficient aeration and mixing should be provided to
 maintain a dissolved oxygen level at greater than 1 mg/H, preferably 2 mg/£
 throughout the aeration tank.   Efforts should be made to keep the MLSS con-
 centration between 4000 and 6000 mg/£.

 The use of a completely mixed aeration cell is strongly recommended as it
 minimizes the effect of fluctuating pH levels in the dairy wastes and provides
 a well balanced system without  additional pH adjustment.  The requirement for
 a pH control facility is thus eliminated.

 As the sludge floe produced from the system treating dairy wastes always con-
 tains filaments and is  non-compact in nature, a conservative surface loading
 of less than 16 m3/m2'd is recommended in the design of the clarifier.  This
was selected based on the loading used at plant C, which was the highest
 among the three treatment systems investigated.  Higher loadings may be used
 if justified by experimental data on sludge settling characteristics.  Sludge
 scraping mechanisms must be provided in the clarifier to facilitate a rapid
movement of the settled sludge  to the hopper for recycling or wasting.  As
 indicated before,  prolonged storage of settled sludge in the clarifier result-
 ed in a significant deterioration of the effluent quality.  It is, therefore,
 essential to operate the clarifier with as little sludge on the bottom as
 possible.  The sludge recycling and wasting equipment should be provided with
 sufficient capacity to  ensure prompt removal of settled sludge.

                                     201

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As  scum is  frequently  formed in the  aeration  cell .arid  carried  over  to  the
clarifier with  the  mixed  liquor,  the clarifier  should  also  be  equipped with
baffle  and  skimming devices  to prevent  the  scum and  other floating  solids
such  as rising  sludge  from discharging  with the effluent.

Based on the performance  data obtained  from the three  treatment  systems  invest-
igated,  a properly  operated  extended aeration activated  sludge system,
designed according  to  the above criteria  should produce  effluents containing
less  than 20 mg/£ of BOD5 and 30  mg/X, of  suspended solids.

ACKNOWLEDGEMENTS

The authors wish to acknowledge the  support of  the management  and staff  of the
three dairy plants .involved  in the study.   Special appreciation  is  expressed
to Messrs. K. Conn  and V.W.  Cairns,  Laboratory  Services  Section  of  the Waste-
water Technology Centre (WTC)  for carrying  out  chemical  analyses and fish
bioassays.  The authors also wish to thank  Mr.  Ron Gillespie of  the Facilities
Services Section,WTC,  for setting up the  pilot-scale clarifiers  and associated
equipment for the study.
                                  REFERENCES
1.   EIFAC Water Quality Criteria for European Freshwater Fish, "Report on
     Ammonia and Inland Fisheries", Food and Agriculture Organization of the
     United Nations, Rome, Technical Report No. 11, 1970.


2.   Brown, D.A. and McLeay, D.M., "Effects of Nitrite on Methemoglobin and
     Total Hemoglobin of Juvenile Rainbow Trout", The Progressive Fish -
     Culturist, 37(1):36-38, 1975.


3.   Perrone, S.J. and Meade, T.L., "Positive Effect of Chloride on Nitrite
     Toxicity to Coho Salmon (Oncorhynchus kisutch)", Journal of the Fisheries
     Research Board, 34:486-492, 1977.


4.   Environmental Protection Agency, Flow Equalization" EPA Technology Trans-
     fer Seminar Publication, 1974.
                                      202

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                    TREATMENT OF BIRD CHILLER WATER FOR
                      REUSE IN FLUMING BROILER GIBLETS

                                     by

                              H. S. Lillard *
INTRODUCTION
There are over 400 federally inspected broiler processing plants in the
United States.  A typical plant processes about 9000 birds per hour or about
70,000 per day.  Modern processing methods make liberal use of water which,
by federal inspection regulations, has to be of potable quality (1).  Water
shortages in certain areas and the rising cost of potable water and effluent
discharge are cause for concern.  Total water usage in the average plant is
about 1 million gallons per day.  One of the largest plants in Georgia,
processes 200,000 birds per day, and reports using 30 million gallons of
water per month at a cost of about $27,000 for potable water and effluent
discharge.

Carawan ^t al., in an EPA sponsored study, showed that the gizzard machine
and giblet flumes required the most water and accounted for about 30% of the
potable water used in the plant surveyed (2).  Therefore, I studied the
giblet operation in the first phase of a program which has two main
objectives:  (1) To examine the requirement for potable water in all phases
of processing except scalding; (2) To determine the feasibility of conserving
water in poultry processing plants by reusing water from a relatively clean
process in another process.  This report is a review of my work to date in
the area of water reuse.  Further details on methodology and results are
available in the original references cited.

FEASIBILITY STUDY OF WATER REUSE

The initial step of studying the feasibility of reusing processing water was
to compare the microbial populations of both water and product from various
processing points in a commercial plant where potable water is used and,
therefore, represents the best available technology.  Table 1 shows that the
level of fecal coliforms in water from the giblet flume was significantly
higher than that in water from the giblet chiller but that the levels in the
products from both sources were not significantly different.  These results
led to the conclusion that quality of processing water is not necessarily
* USDA, SEA, Richard B. Russell Agricultural Research Center, P. 0. Box 5677,
  Athens, GA.  30604

  Mention of firm names does not imply endorsement of the products by the
  U. S. Department of Agriculture.  No discrimination or preference is
  intended.  The use of firm names and products is for identification only.

                                    203

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 directly  related to  quality of  product  and,  although processing water washes
 off  loosely  attached microorganisms,  bacteria  that  are attached to the skin
 of broilers  probably remain attached  and  cannot be  washed off  (3).


                 TABLE  1.  MICROBIOLOGICAL QUALITY OF WATER AND
                          PRODUCT FROM  GIBLET  FLUMES AND CHILLERS
WATER (52 samples) 1
Sample Fecal
Source (mean
Giblet flume
Gib let chiller
coliforms
Iog10/ml)
3.00
2.10
Salmonellae
No.+/total
15/52 a
18/52 a
PRODUCT (78 samples)
Fecal coliforms
(mean log1Q/ml)
2.32 b
2.30 b
Salmonellae
No.+/total
4/78 c
4/78 c
   The same lower case letter follows values which are not significantly
   different at the 5% level.
Results of a microbiological evaluation of water from another processing
plant are shown in Table 2.


              TABLE 2.  MICROBIOLOGICAL QUALITY OF PROCESSING WATER
                                    Mean log-0/ml
                                 (Based on 26 samples)
Water
Source
Neck flume
Neck chiller
Bird chiller
Aerobic,
counts
3.81 a
3.87 a
3.49 a
Fecal -
coliforms
3.11 b
3.44 b
2.48 b
   The same lower case letter follows values which are not significantly
   different at the 5% level.
                                    204

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 These  data  show that  aerobic  counts and fecal  coliform levels did not differ
 significantly in processing water  from the neck flume, neck chiller and the
 bird chiller (4).

 These  two surveys showed  that for  water and energy conservation, water from
 the bird chiller might be used to  flume and cool giblets without adversely
 affecting product quality.

 FLUMING NECKS WITH UNTREATED  BIRD  CHILLER WATER

 Necks were  used in the next phase  of this study because they represented the
 least  cost  to the processor.   A 1/4 scale simulated giblet flume was
 constructed in cooperation with a  commercial processor (Fig. 1).  In an area
 away from the main processing plant, necks were flumed with potable water or
 with bird chiller water pumped from the overflow.  Holding time of necks and
 ratio of necks to water in the simulated flume were the same as for the
 commercial  flume in this  plant.  Necks flumed with bird chiller water were
 compared with those flumed with potable water in the simulated flume.
 Salmonellae incidence and levels,  fecal coliform levels and shelf-life were
 the same for necks flumed with untreated bird chiller water and those flumed
 with potable water.  However,  aerobic counts were 1/4 log higher for necks
 flumed with bird chiller  water  than for necks flumed with potable water (5).

 To eliminate this  difference  in counts treatment of the chiller water was
 necessary.   Regulatory approval for reuse of chiller water without further
 improvement would  be denied on the basis of esthetic considerations.
 Therefore,  chlorination of bird chiller water without further improvement
 was not considered the best approach.  Rogers  (6), in an EPA sponsored study,
 screened various methods  for  removing organic matter from chiller water.  The
 method he found  the most  promising was to filter the chiller water through
 diatomaceous  earth in a pressure leaf filter.  Therefore, I next undertook to
 evaluate the  microbiological,  chemical and physical properties of bird
 chiller water filtered through  diatomaceous earth (DE) (7), and to evaluate
 the effect  on necks of fluming with DE-filtered chiller water with and
without chlorination  (8).

 TREATMENT OF  CHILLER WATER

Figure 2 is  a schematic diagram of a DE pressure leaf filter and the line of
 flow.  A 1:1  w/w mixture  of two grades of DE (Speedflow plus Dicalite 4200)
was used to  coat the 6 leaves prior to filtering the chiller water.

Filtration  of bird chiller water through diatomaceous earth significantly
 lowered solids and grease contents (Table 3).

Filtration  also improved  the microbiological quality of chiller water.
Reductions  in aerobic counts and fecal coliforms were significant at the
 1% level (Table 4).
                                    205

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NJ
O
            1/4 SCALE FLUME
            (I 1/2" PVC PIPE)
                                  -POTABLE WATER
                                           FILTERED CHILLER WATER
CONTROL VALVE
                                                 COLLECTION SCREEN
                                                Figure 1.  Simulated giblet flume  (1/4 scale),
                                                         as shown by Lillard (1978) in
                                                         reference #5.
                          55 GAL. WATER
                         COLLECTION TANK
                  GIBLET
                  PUMP

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                  CHILLER
                   WATER
                                        DIRECTION OF FLOW

                                            CHILLER WATER
                                            PRE-COATINGOF FILTER LEAVES
           AGITATOR
       D.E.
    SLURRY
K3
O
            PUMP
Figure 2.
                                                                   INJECTOR
                                                                                      EXIT
                                       PUMP
                                                                REGULATOR
                                                               CHLORINE
                                                                 TANK
                     Schematic diagram of pre-coat tank, pressure leaf filter, and chlorinator.
                     Arrows show the line of flow.  As shown by Lillard (1978) in reference #7.

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                     TABLE 3.   CHEMICAL PROPERTIES  OF CHILLER
                               AND FILTERED CHILLER WATER
                                      Mean mg/1
                                 (Based on 18  samples)
 Water
 Source

 Chiller water

 Filtered  chiller water
   (1:1 w/w Speedflow +
    Dicalite 4200)

 Percent reduction due
   to  filtration
Suspended
Solids

    160

      9
     94
Dissolved
Matter

   414

   324
    22
Grease

  137

   16
   88
                  TABLE  4.  MICROBIOLOGICAL QUALITY OF CHILLER
                            AND FILTERED CHILLER WATER
Source


Chiller water

Filtered chiller water

Filtered, chlorinated
  chiller water
                                Mean log,_/ml
Aerobic
count

  5.12

  3.72

  1.45
Fecal
coliforms

   3.13

   1.33

   <0
  No.  of
  samples

    18

    18

    10
Microbiological quality of the water was further improved by chlorination.
Removal of organic matter from chiller water by filtration made it possible
to chlorinate effectively with low levels of chlorine gas (26-28 ppm)
instead of the 48-50 ppm required for untreated chiller water.  Table 4
shows that after chlorination, filtered chiller water was comparable in
microbiological quality to potable water (7).

The filtered water was clear, and relatively colorless and transmitted
91-100% of light at 540 nm; it was not esthetically objectionable; and it
visually resembled potable water.  Figures 3 and 4 show the extremes in
color and clarity of filtered chiller water compared to potable water.
                                     208

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to
              Figure 3.  Water samples (left to right):  from the bird chiller, filtered chiller water
                         and potable water as shown by Lillard  (1978) in reference #7.

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to
H
a
               Figure 4.   Water samples (left to right) from the commercial flume, bird chiller, filtered

                          chiller water and potable water as shown by Lillard (1978) in reference #7.

-------
 Fig.  3 shows the maximum color  obtained;  Fig.  4  shows  the  clearest water
 obtained,  with or without chlorination, which  resulted in  100% light
 transmission at 540 nm.

 In Fig.  4  clarity of the filtered  chiller water, unfiltered chiller water or
 commercial flume water is best  compared with that of potable water by the
 ease  with  which markings on the beakers can be seen through the water.  When
 necks are  flumed with potable water,  the  appearance of the water changes
 within seconds of the necks entering  the  flume.  Fig.  4 shows the dark
 (bloody) characteristics of commercial flume water and the grease floating
 on the surface.   By contrast, filtered chiller water is relatively clear,
 colorless  and free of grease.   Considering the chemical, physical and
 microbiological properties of the  filtered chiller water discussed above and
 the rapid  deterioration  of potable water  in the neck flume, the requirement
 for use of potable water in neck flumes does not seem  necessary.

 Necks  flumed in the simulated line with potable water  were then compared with
 necks  flumed with filtered chiller water  and with filtered, chlorinated
 chiller water.   Temperature of  necks  flumed with chiller water varied
 seasonally.   However,  during the course of this study, necks flumed with
 chiller water were 12 C  cooler  than necks flumed with  potable water.  Table
 5  shows  that,  microbiologically necks flumed with potable  water and necks
 flumed with filtered  chiller water or filtered, chlorinated chiller water
were  not significantly different.


        TABLE 5.   MICROBIOLOGICAL CHARACTERIZATION OF NECKS FLUMED WITH
                  POTABLE WATER, FILTERED  CHILLER WATER AND FILTERED,
                  CHLORINATED CHILLER WATER
Source of                    Mean logiO/ml
flume                   Aerobic..       Fecal     -      Mean number
water	               counts         coliforms     days of shelf-life

Potable water            5.48 a (12)    3.75 c (12)         14.2 e (30)

Filtered chiller water   5.45 a (12)    3.47 c (12)         14.2 e (30)


Potable water            5.17 b (10)    3.50 d (10)         11.7 f (25)

Filtered, chlorinated    5.27 b (10)    3.53 d (10)         13.0 f (25)
  chiller water


   The same lower case letter follows values which are not significantly
   different at the 5% level.  The number of samples per mean is given
   parenthetically.
                                     211

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 CONCLUSIONS

 In  accordance  with federal  regulations  and  technology, giblets are flumed
 with  potable water.  My work has  shown  that product quality can be equally
 good  when water of somewhat less  than potable quality is used;  necks flumed
 with  chiller water filtered through  diatomaceous earth were microbiologically
 equal in all respects  to  necks  flumed with  potable water.  Fluming giblets
 with  filtered  chiller  water would reduce  the demand of poultry processors
 for potable water  and  energy, and also  would reduce the amount of water and
 organic matter discharged into  municipal waste treatment systems.

 According to estimates a  processor could  recover the cost of a pressure leaf
 filter  in less than  2  years (7).
                                 REFERENCES

1.  USDA.  Poultry Inspection Regulations.  U. S. Department of Agriculture,
    FSQS, Washington, D. C.  (1972).

2.  Carawan, R. E., Crosswhite, W. M., Macon, J. A. and Hawkins, B. K.
    Water and waste management in poultry processing.  EPA Project 12060
    EGV, Office of Research  and Development, U. S. Environmental Protection
    Agency, Washington, D. C.  20460  (1974).

3.  Lillard, H. S.  Microbiological characterization of water for recycling
    in poultry processing plants.  J. Food Sci. 42:168 (1977).

4.  Lillard, H. S.  Evaluation of bird chiller water for recycling in giblet
    flumes.  J. Food Sci. 43:401 (1978).

5.  Lillard, H. S.  Broiler necks flumed in recycled bird chiller water.
    Po. Sci. 142 (1978).

6.  Rogers, C. J.  Unpublished data.  "Recycling of water in poultry
    processing plants," First Interim Technical Report, EPA Projects-800930.
    Office of Research and Development, Industrial Environmental Research
    Laboratory, U. S. Environmental Protection Agency, Cincinnati, Ohio,
    45268.

7.  Lillard, H. S.  Improving quality of bird chiller water for recycling by
    diatomaceous earth filtration and chlorination.  J. Food Sci.  In Press
    (1978).

8.  Lillard, H. S.  Evaluation of broiler necks flumed with untreated or
    diatomaceous earth filtered, filtered and chlorinated chiller water.
    J.  Food Sci.  In Press (1978).
                                     212

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                 DESIGN AND OPERATION OF A VEGETABLE OIL PLANT
               WASTEWATER TREATMENT  SYSTEM FOR FUTURE STANDARDS

                                     by

                              N. J. Smallwood*
 INTRODUCTION
 Lou Ana Foods,  Inc., operates a medium-size vegetable oil refining and
 processing  plant  in Opelousas, Louisiana.  The plant is operated continuously
 except  for  shutdown on major holidays.

 Because of  ownership and management changes in the early 1970's, attention
 was not directed  to achieving compliance with the Federal Water Pollution
 Control Act until 1975.  It was then concluded that the company did not have
 the technical resources to successfully handle the project.  A search was
 initiated to obtain the necessary expertise.  By June, 1976, the company was
 able to acquire the services of a competent consultant and recruit experienced
 technical management who were able to utilize the best methods and designs
 which had evolved from the vegetable oil industry.  The result of the work
 has been to meet  the NPDES schedule of compliance and effluent limits, and,
 we  believe, to  provide a system for meeting future standards.  The purpose of
 this presentation is to share with the vegetable oil industry and the
 Environmental Protection Agency our concept, design, operating mode, results,
 and conclusions pertaining to vegetable oil wastewater treatment.

 SYSTEM  OBJECTIVES

 The scope and design of the Lou Ana Foods' wastewater treatment project were
 to  meet  the following objectives:

 1.   Meet the NPDES  schedule of compliance and effluent limits.
 2.   Achieve a level of reliability to not jeopardize continuity of plant
     operations or exceed effluent limits.
 3.   Provide water treatment capacity for future expansion of production
     facilities.
 4.   Minimize operating costs.
 5.   Improve the esthetic image of the plant.
 6.   Satisfy Spill Prevention, Control, and Counter Measure requirements.
 7.  Accommodate future effluent standards with minimum capital  cost.

WASTEWATER  EFFLUENT FROM VEGETABLE OIL PROCESSING

 Sources and Characterization

The  treatment system was designed to handle three categories of water effluent
 from manufacturing operations:
*Vice-President, Operations, Lou Ana Foods, Inc.,  Opelousas,  Louisiana.

                                     213

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 1.  Process Wastewater:  Water which has been in contact with the product
    stream and  contains  some concentration of oil, processing reagents, and
    sludge material derived from crude vegetable oil.
 2.  Rainwater Runoff:  Rainwater which falls on outside surface areas and
    initially washes away drips and spills from tank car and truck loading/
    unloading stations and tank fields.
 3.  Non-Contact Cooling  Water:  Wellwater remaining free of contamination
    while circulated once through a closed piping/coil system to maintain
    process temperature  control.

 Water  Stream Separation  and Collection

 The system includes the  following separation and collection by category:

 1.  Process Wastewater:  The wastewater from each major source is individually
    piped for gravity discharge into a collection sump adjacent to the main
    processing  building.  Routine, visual observation, sampling and analysis
    can be made of each wastewater stream to detect anomolous conditions.
    From the collection  sump, the wastewater flows by gravity through an
    underground line to  the pre-treatment sump which is equipped with a
    mechanical  agitator.
 2.  Rainwater Runoff:  Outside areas subject to oil leaks, drips and spills
    are provided with concrete mats and dikes for containment.  Underground
    drainlines  are installed for gravity flow of rainwater/oil to a collection
    sump adjacent to the pre-treatment sump for process wastewater.  The two
    adjacent sumps have a connecting line for gravity flow from the rainwater
    sump to the process wastewater sump.  The connecting line contains a
    remote operated shutoff valve actuated by a raingauge device.  Thus, in
    the event of a rain, the initial rainwater collected by the concrete mats
    and dikes wash and carry away any oil spillage to the rainwater collection
    sump and on to the process wastewater pre-treatment sump.  If the rainfall
    continues for a prolonged period, after a preset level is reached in the
    raingauge,   a signal  is transmitted to a controller which will close the
    valve in the connecting line between sumps.  The water level in the rain-
    water sump will rise until it reaches a high level overflow which will
    conduct,  by  this time, essentially pure rainwater to the non-contact
    cooling water outfall.
    Note:  If rainwater runoff were allowed to indefinitely flow into process
    wastewater  pre-treatment sump, then the subsequent treatment system would
    be overwhelmed by the quantity of water.  The other alternative of sizing
    the subsequent treatment system to handle the complete rainfall load is
    not economically feasible.
3.  Non-Contact  Cooling Water:  Non-contact cooling water lines are piped to
    discharge into a flash tank.  Any steam generated will flash and vent to
    the atmosphere.  From the flash tank,  water is pumped to two oil-water
    separating decanters connected in series for removal of any entrained oil
    which could  result in event of coil failure.  Clean water underflows from
    the second decanter for gravity discharge through a weir box and a final
    gravity separator and on to the non-contact cooling water outfall.
                                     214

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 TREATMENT TRAIN

 The sequence of processes in the treatment  train  is  pH adjustment, gravity
 separation of floatable oils,  flow equalization,  neutralization, dissolved air
 flotation, biological treatment  and clarification.

 pH Adjustment

 A pH in the two to three range is required  to achieve optimum gravity separa-
 tion of floatable oils.   Adjustment of  pH is achieved by a control loop which
 monitors the wastewater  in the pre-treatment sump and controls sulfuric acid
 addition to the sump for lowering pH as required.

 Gravity Separation of Floatable  Oils

 Wastewater is pumped from the  pre-treatment sump  to  four decanters for sepa-
 ration of floatable oils.  The wastewater stream  enters the first two decanters
 connected in parallel through  a  horizontal distributing nozzle located in the
 center of each vessel.   Oil-water separation occurs  in the horizontal center
 zone of each vessel with the floatable  oil  subsequently rising to the top of
 the liquid column.   The  accumulation of oil is pumped off each day by means of
 a swinging suction.  The water fraction is continually drawn off by gravity
 underflow to the second  two decanters connected in series for repetition of
 the process.   Some of the solids in the wastewater stream settle to the bottom
 of the decanters.   The decanter  system  is sufficiently sized to operate suc-
 cessfully with one parallel branch valved out of  service for sediment removal.

 Flow Equalization

 Flow equalization  for optimum  operation of dissolved air flotation is achieved
 by means of  eight  12,000 gallon  capacity hold tanks.  The hold tanks provide
capacity for  a minimum of 16 hours accumulation of wastewater at the present
 flow rate of  85 gpm.   Other than for flow equalization, the hold tanks function
 as settling  tanks  for further  removal of settleable  solids and gravity separa-
 tors for further recovery of floatable  oil.  The hold tanks can be individually
 valved out of service for removal of accumulated  floatable oil and sediment
 without disrupting  normal operation of  the system.

 Neutralization

 Wastewater is pumped  from the  hold  tanks to the dissolved air flotation
 process.   On  the suction side  of  the transfer pump, caustic soda is injected
 to  neutralize the water  stream.   Primary neutralization control is provided
 by an  automatic  control  loop.  Manual control is  provided for backup operation.

 Dissolved  Air Flotation

 Neutralized water and a  cationic  polymer coagulant are discharged into a two
 compartment  flocculation tank  with  high and low speed mixing agitators
 respectively.   From the  flocculation tank, the water overflows to the inlet
 of  a center-positioned coagulation  tube in the flotation cell.  Water under-
 flows  from the flotation cell  through six exterior riser tubes to a top

                                      215

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 peripheral collection ring for both recycle pressurization and  gravity
 discharge to an aerated lagoon.  Water recycled at about  350 gpm is  fully
 pressurized and is injected with an anionic polymer coagulant aid prior  to
 discharge back into the coagulation tube.  Removal of  float is  accomplished
 by a top rotating skimmer.  The DAF is sized to provide a surface loading of
 less than 3.0 gpm/sq ft.

 Biological Treatment

 Biological treatment is accomplished by means of an aerated lagoon.  The
 lagoon capacity is 11.2 million gallons with a normal  water depth of 16 feet.
 A redwood baffle separates the lagoon into two sections.   Aeration is achieved
 by eight 40-horsepower floating aerators.  Liquid fertilizer is injected into
 the lagoon influent to supply nitrogen and phosphorus  for the microorganism
 life processes.   The perimeter wall of the lagoon is concrete lined  to preclude
 erosion.  At the present wastewater influent rate,  the lagoon provides 90 days
 of retention time.

 Clarification

 Treated  water is pumped from the aerated lagoon to  a clarifier  for separation
 of the biological sludge.   The clarifier is sized for  an  overflow rate of
 450 gpd/sq ft of surface area and a retention time  of  three hours.  Clarified
 water  gravity flows to a final monitoring station.   The biological sludge is
 recycled back to the inlet side of the aerated lagoon.

 Final  Monitoring

 Prior  to discharge to the  outfall,  the treated water flows  through a monitoring
 station  for  flow measurement,  sampling,  and pU recording.

 OPERATION

 Time

 With more than 16 hours  hold  capacity,  the dissolved air  flotation process
 (DAF)  is  operated  only eight  hours  per day.   Furthermore,  the clarifier is
 operated  and  treated  water  is  discharged  only during the  period that the DAF
 is  in  operation.   Operating  the  critical  elements of the  system only during
 the day  shift provides the opportunity for  maximum attention and control.

 Reliability

The treatment system  in  contact with acidic wastewater is constructed
 primarily of fiberglass  reinforced  plastic  (FRP).  Consequently, it is essen-
 tially maintenance  free.  Both pH control  loops for sulfuric acid and caustic
 soda addition respectively have backup manual  control.  Critical pumps in the
 system are paired and  are installed in parallel.  Operation of the total
system would be seriously impaired only in  the event of mechanical breakdown
of either the DAF or clarifier.  However, up  to 16 hours per day repair time
is available for both  the DAF or clarifier.  With excess retention time
available in the aerated lagoon, the DAF could probably be bypassed for up to

                                      216

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five days without significant consequences.  Sufficient freeboard is
available in  the aerated lagoon to hold water for at least five consecutive
days to accommodate major repair of the clarifier.

RESULTS

Completion

Construction  of the wastewater treatment system was completed and startup
achieved to meet the July 1, 1977, NPDES schedule of compliance.

Performance

Performance results from operating the treatment system eight months are given
in Table 1.

Project Cost

The total cost of the treatment system project was $1.5 million.

Operating Expense

Annual operating expense for the total system based on actual experience to
date is given in Table 2.

Reliability

The system has been operated continually since startup without any significant
problems.  However, the necessity of manual pH control backup and other
reliability features described has already been demonstrated.

CONCLUSIONS

With disciplined operation and maintenance of the treatment system, it appears
that meeting BOD, O&G and pH limits will not be a problem.

It is too early in the life of the system to predict the expected long-term
performance on suspended solids removal.  After the microorganism population
in the aerated lagoon has reached optimum level, it will be possible to better
access clarifier performance and suspended solids removal.

System performance can be further improved by optimizing treatment conditions
for each type of vegetable oil refined.  Wastewater from cottonseed, corn,
soybean and sunflowerseed oil refining/acidulation is relatively easy to treat.
Coconut and peanut oil wastewater being more emulsified is more difficult to
treat.

Use of decanters and hold tanks for floatable oil and settleable solids removal
is assessed to be better than conventional fat traps  or API type separators
in overall operation.
                                      217

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                TABLE 1.  WASTEWATER TREATMENT SYSTEM PERFORMANCE

             Effluent Characteristics for Treatment Train Processes

           Process                            Concentration (mg/1)
                                      COD      BOD     O&G      TSS    £H

 1.   Collection-pH Adjustment Sump   38,333   10,850   8,107    12,461   2.1

 2.   Decanter                          -        -      2,635     9,014   2.1

 3.   Equalization - Hold             15,000    7,692     577      905   2.2

 4.   DAF                              4,053    5,972     282      589   6.5

 5.   Aerated Lagoon                     547      123       4      608   7.0

 6.   Clarifier                           161       16       4        66   7.2

                  Performance for Each Treatment Train Process

       Process                               Percent Removal
                                  COD        BOD       O&G       TSS

 1.   Decanter                        0          0      67.5      27.7

 2.   Equalization - Hold          60.9       29.1      78.1      90.0

 3.   DAF                          73.0       22.4      51.1      34.9

 4.   Aerated  Lagoon               86.5       97.9      98.6

 5.   Clarifier                     70.6       87.0         0      89.1

 6.   Total Treatment  System        99.6       99.8      99.9      99.5

              Treatment Performance with Respect to NPDES  Limits

                                 Minimum           Average          Maximum

Flow Rate (MGD)                   0.066             0.121             0.178

BOD  (Ib./day)                     4                17  (104)          47 (256)

O&G  (Ib./day)                     1                4  (41)           10 (104)

TSS  (Ib./day)                    17                68  (104)         156 (256)

pH                                7.0  (6.0)        7.2               7.4  (9.0)

Note:  NPDES limit conditions given in parenthesis


                                      218

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TABLE 2.  ANNUAL OPERATING EXPENSE FOR THE TOTAL WASTEWATER TREATMENT SYSTEM



              Expense Item                                Cost

       1.  Labor                                        $29,370

       2.  Operating Supplies
           a.  Sulfuric acid                             20,672
           b.  Caustic soda                              34,712
           c.  Flocculant agents                         24,000

       3.  Maintenance (Material & Labor)                27,000

       4.  Utilities
           a.  Steam                                      4,876
           b.  Electrical Power                          49,304

       5.  Sludge Disposal                               17,600

       6.  Miscellaneous                                  5,000

       7.  Depreciation                                  79,320

            TOTAL                                      $291,854

       Wastewater Treatment Cost = $6.89/1,000 gallons
                                     219

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Disposal of sludge from the treatment system is a challenging problem.   We are
still seeking a satisfactory, long-term solution.

Overall, based on results achieved to date, it can be concluded that the
wastewater treatment system has and will continue to meet design objectives.
                                     220

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                       DISSOLVED AIR FLOTATION TREATMENT
                                         OF
                        GULF SHRIMP CANNERY WASTEWATER

                                         by

                 A. J. Szabo, Larry F. LaFleur,  and Felon R. Wilson*
INTRODUCTION

The plant scale dissolved air flotation project for treatment of a Gulf Coast shrimp can-
nery wastewater and other cannery pollution abatement measures are discussed.  The sys-
tem was installed as a joint  industry-government demonstration project to establish achie-
vable levels of pollutant removals from wastewaters during shrimp processing and during
oyster processing.  This project was the follow-up of an earlier pilot study sponsored by
the American Shrimp Canners Association and the Environmental  Protection Agency (1).

As reported by Ertz/etal/to the Eighth National Symposium on Food Processing wastes (2),
the dissolved air flotation process has been tested on a pilot scale for several seafoods and
has been installed full scale to treat tuna and other fish wastewaters.  This treatment pro-
cess has advantages of minimal land requirements and quick start up, and is particularly
adaptable to the seasonal, intermittent operations of the  land-poor  Gulf shrimp processors.
Chemical  coagulation and pH  adjustment to precipitate colloidal and suspended solids in
proteinaceous seafood wastewaters for removal by flotation is considered to be a practica-
ble and presently available technology which could be substituted for the less adaptable
biological  process.  Plant scale system performance should, therefore, be of interest to in-
dustry and  to regulatory and other governmental  agencies.

BACKGROUND

Gulf shrimp canners have for many years been concerned with their  wastewater disposal
problem.  These processors have sought solutions individually and collectively.  Several
manufacturers and suppliers have installed and operated test units, ranging from screening
and flotation to reverse  osmosis.   This project sought to develop practicable  wastewater
management and treatment data from a plant scale installation under normal  cannery oper-
ating conditions.   The association (ASCA) obtained a demonstration grant and funded the
studies, design,  installation and operation of the facilities at the Violet Packing Company
cannery south of New Orleans.  Information obtained will be of assistance to all shrimp
processors in their pollution  abatement programs.
  Principal, Mechanical Engineer, and Sanitary Engineer, respectively,
  Domingue, Szabo & Associates, Inc., Consulting Engineers, Lafayette,  Louisiana

                                        221

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 CANNERY WASTEWATER

 The Violet Packing Company shrimp and oyster processing and canning layout schematic
 is shown in Figure 1.  Wastewaters flows from unit processes were characterized at the
 start of the study.  Sources, volumes and concentrations as developed in  1975 are shown
 in Table 1.
          TABLE 1.  UNIT PROCESS WASTEWATERS, GULF SHRIMP CANNERY
                            Flow
 Process
Gallons/     M^/KKG   % of
1000 IDS.                Total
    Concentration-mg/l
BODS     O & G   TSS
Receiving
Peelers
Separators
Graders
Deveiners
Canning Room
143
2,825
572
237
1,289
2,373
1.193
23.550
4.770
1.976
10.750
19.760
1.9
38.0
7.7
3.2
17.3
31.9
4,278
2,375
899
395
366
781
650
257
34
12
14
17
1,711
963
401
190
211
329
After study, a water conservation and wastewater management plan was adopted and the
cannery made considerable improvement which affected water use.  Total wastewater
volumes were reduced by 43% from 7,728 gallons per 1000 pounds (64.4nrYKKg) of raw
shrimp processed to 4,420 gallons per 1000 pounds (36.9 mVKKg) between 1974 and 1977.
Cannery pollution abatement procedures resulted in the significant reduction of total pollu-
tants in the wastewater during this period.

The treatment facilities were designed to treat screened wastewater from the cannery at a
flow rate of 700 gallons per minute (2.6 mvminute).  By the time the system was put into
operation, the flow had been reduced to 500 gpm (1.9 m3/minure). The concentrations
of the Violet  Packing Company 1977 wastewater  flows after pretreatment through 10 mesh
(0.85 mm) vibrating screens are given in Table 2.
                                       222

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                                                               INSPECTION
                                                                   a
                                                     SEPARATORS  WEIGHING
                                                              OYSTER BOAr
                                                              DOCKING AREA
                                             SHRIMP  PRODUCT FLOW
                                             OYSTER PRODUCT FLOW
                                             WASTEWATER
VIOLET  PACKING   CO.
   VIOLET,  LOUISIANA
        Figure 1

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         TABLE 2.  GULF SHRIMP CANNERY WASTEWATER CONCENTRATIONS
Parameter
BODS
Soluble BOD5
COD
Soluble COD
TKN
Oil & Grease
TSS
VSS
pH (Units)
Range
(mg/l)
450-1620
265-1120
1388-3920
1032-2960
156-344
28-169
240-1020
188-892

Average
(mg/l)
1070
720
2775
1880
260
115
505
425
7.5
As evident from the range of values in Table 2, the character of wastewaters from shrimp
canning operations is not consistent.  The lack of uniformity is due to the variation in
size,  age and type of raw product and to variations in processing rates and water use.

TREATMENT FACILITIES

A multi-modal dissolved air flotation  system was installed at the Violet cannery in 1976.
It consisted of complete facilities to treat the cannery wastewaters in full flow pressuriza-
tion,  partial flow pressurization or recycle pressurization modes.  An influent flume flow
meter recorder-controller served to  proportion chemical  dosages.  Acid (or caustic) dos-
ages into the influent surge tank were pH meter-recorder-controller actuated and  equali-
zation flow was returned to this tank.   Treatment process pumps pressured the injected air
and wastewater mixture into the retention tank at full flow mode or pumped into the floc-
culation  tank in  partial or recycle modes.  Coagulant was added to the influent flume
and coagulant aid was injected into the flotation cell influent line downstream from the
manual pressure control valve and/or  into the flocculation chamber.  Wastewater  entered
the circular flotation cell  center coagulation chamber in which pressure was released and
the suspended solids-air bubble mixture moved upward and radially.  Floated solids accu-
                                        224

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mulcted on the surface as skimmings and were swept by four rotating scraper arms over a
beach and chute into the skimmings hopper.  Clarified wastewater flowed radially and
downward to effluent tubes, up and over the circumferential weir and into the effluent
tank.  Prior to discharge, pH was adjusted with caustic feed controlled by the effluent pH
meter-recorder.

In the partial  flow pressurization mode, part of the flow (50%) was routed as above for
the full flow mode and the remainder of the wastewater flow was pumped to the  vertical,
cylindrical floccularion tank with mixer, after pH adjustment and coagulant feed, for a
20 to 30 minute slow mix.  It then flowed by gravity to the center, coagulation chamber
of the flotation cell where it was mixed with the pressurized flow containing coagulant
and coagulant aid.

Recycle pressurization was accomplished by routing all chemically treated influent waste-
water to the flocculation tank and pressurizing clarified flotation cell effluent through the
retention tank and into the coagulation chamber, where the dissolved air and flocculated
wastewater were mixed and released in the flotation cell. Figure 2 shows the DAF layout.

The DAF treatment system included storage tanks for liquid alum, liquid caustic, and con-
centrated sulfuric acid.   The flow meter recorder-controller,  pH controller-recorders, pro-
portioning chemical feeders for acid, alum and coagulant aids (two units), power supply
meter, and central panel were designed for system control  and data collection.  An on-
site laboratory was installed and equipped to enable analyses to be timely made.

OPERATIONS

In order to confirm pilot plant findings on chemical coagulant and coagulant aid dosages,
bench tests were made on Violet Cannery wastewater.  Maximum precipitation and clari-
fication was repeatedly shown to occur at pH 4.5 to 5.0, although ranges from about 2. 0
to 11. 0 were investigated.  Coagulants tested were: alum, chitin (chirosan),  glucose tri-
sulfate (GTS), iron salts, lignosulfonate, and cationic polymer.  Coagulant aids used
were: Magnifloc 835A and  Magnifloc 845A, as recommended from the pilot study.  Pro-
mising results were obtained with alum, lignosulfonate (PRA-1),  and  cationic polymer
(507C) as coagulants combined with polymers 835A and 845A.

Operation of the new DAF  wastewater treatment system met with start up problems that
"just couldn't happen here".  Completion of equipment delivery and  installation was
about two weeks after start of the heavy canning season.  Problems with the flow meter-
controller,  chemical pumps, pH meter-controller, process pumps, flocculator, flotation
cell, and electrical system were slowly resolved while the supply of product was being
used up and  was dwindling. By the time some of the equipment and installation difficul-
ties were resolved, the primary, summer season had passed.  Other discrepancies in the
flotation cell coagulation tube and the inadequacy of skimming arms  were rectified and
some operations were possible during the limited fall  1976 canning season.  Other necess-
ary modifications were completed prior to the 1977 summer season so  that full operations
                                        225

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                              CANNERY
                             WASTEWATER
                               SCREENS
                             LEGE ND
                SCREENINGS
                  TO-«
                 DISPOSAL
                                  RAW WASTEWATER

                                  FULL FLOW MODE

                                  RECYCLE MODE

                                  PARTIAL MODE
     FULL FLOW a
     PARTIAL MODES
      AIR
   SATURATION
     TANK
                                   RECYCLE 8
                                 PARTIAL MODES
RECYCLE
 MODE
   AIR
PRESSURE
RELEASE
 VALVE
  ADJUST
                        SKIMMINGS
                           TO
                         DISPOSAL
        TREATED
        EFFLUENT
  DAF  TREATMENT  PLANT  SCHEMATIC
                        Figure 2



                           226

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and data collection were possible.

The dissolved air flotation treatment plant was first operated as a physical treatment sys-
tem, without any chemical addition.   Limited removals of BOD5 and oil and grease were
accomplished, and solids existing in suspension were effectively reduced.  Removals
attained were: BODS - 3.5%; Oil and Grease - 10.5% and TSS - 69.4%.

Physical-chemical treatment was the primary objective and most efforts were directed
toward obtaining optimum performance.  In all circumstances, pH was controlled between
4.5 and 5. 0 by the addition of sulfuric acid.  Coagulants were added to the system influ-
ent stream and coagulant aid was injected into the pressured flow entering the flotation
cell and/or into the flocculation tank.  Effective pH control  and coagulant-coagulant
aid additions resulted in significant removals of the conventional pollutants. Full flow
pressurization mode average removal performance levels are shown  in Table 3 by types of
coagulant applied.
             TABLE 3.  DAF TREATMENT OF GULF SHRIMP WASTEWATER,
                       COAGULANT COMPARISON

Coagulant                 Coagulant Aid        	Per Cent Removal	  No.
-Dosage (mg/l)            -Dosage (mg/l)        BODS     TSS       O&G   Test
                                                                            Runs
PRA-1
60
507C
300
Alum
219
835A
2.5
835A
5.0
835A
3.9
56.7 73.3

68.5 56.8

48.5 62.7

67.7 3

71.1 2

87.3 23

Pressurization modes were compared using alum and polymer.  Influent flow pH was adjust-
ed to 5.0, alum was added to the influent, and polymer was added to the pressure control
valve discharge.  These data (Table 4) were collected under carefully controlled operating
conditions and reflect maximum attainable results.
                                       227

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             TABLE 4.  DAF TREATMENT  OF GULF SHRIMP WASTEWATER,
                        MODAL COMPARISON
Mode
Full Flow
Partial
Recycle
Overall
Average
Average
Alum
(mg/0
219
345
283
271
Average
835A
(mg/l)
3.9
6.1
7.5
5.8
PerCent
BOD5
48.5
55.0
64.6
56.5
Removal
TSS
62.7
72.6
64.8
65.6

O&G
87.3
83.4
83.6
85.0
 It was realized that average industry treatment system operation could vary significantly
 from the atypical project conditions.  In order to simulate anticipated conditions, several
 unattended, automated test runs in the full pressurization mode were sampled.  Removals
 achieved with average dosages of 303 mg/l of alum and 3.7 mg/l  of polymer were:
 BODS -  54.5%; TSS - 34.3% and O & G - 84%.

 Because  of the warm weather and the existing adjacent housing developments which pre-
 vail at most Gulf shrimp cannery locations, it is necessary to take positive action to con-
 trol odors and insects around the wastewater treatment system, and the total cannery.
 The wastewater and the solids which are developed are highly putrescible and very odor-
 ous.  Frequent washdown and use of insecticides is necessary.  Treatment system tanks
 must be drained and washed when intermittent operations result in no fresh wastewater
 flows for 8 to 12 hours or longer. The additional pollutants discharged under such condi-
 tions can be calculated and cause  further reduction in the effectiveness of the treatment
 system operation.

 Inherent characteristics of shrimp processing operations contribute to some of the  condi-
 tions which limit consistent and higher levels of  achievable pollutant removals.   Raw pro-
duct types and sizes and age variations, processing rate changes and adjustments, stop
and go and intermittent operations and possibly other factors are involved.  The variable
wastewater flow was found  to be extremely sensitive to coagulant  dosages and frequent
adjustments were needed.   The study plant air  injection capabilities were limited.  Air to
solids ratios may, therefore, not have been fully investigated in the operation of the de-
monstration plant., An additional air source would have been helpful.

Solids developed by flotation separation and skimming from the surface of the dissolved

                                       228

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air system main cell consist of about 6% solids, air and liquid.  These solid wastes are
highly odorous and objectionable and  are difficult to store and handle.  Bench scale tests
were made to concentrate the solids by centrifuging, by heating, and  by gravity.  Chemi-
cal conditioning with a bench scale Purifax unit demonstrated a degree of stabilization.
A pilot scale evaporator-dryer unit by Convap was operated.  It appeared that skimmings
concentration to about 25% solids may be feasible, with a corresponding three fourths
reduction in volume.  More investigation of waste solids handling, concentration and
disposal is urgently needed to solve this real problem of DAF system operation on seafood
wasrewaters.

COSTS

Computations have been made of costs of DAF  system installation and operation to treat
Gulf shrimp processing wastewaters.  These costs range from $0.38 to $1. 03 per case of
24-4 1/2 oz.  (128g) cans of shrimp,  depending upon the annual production.  Costs for  a
typical 8-peeler  cannery are from $120,000 to $132,000 per year, varying with the num-
ber of days of operation, the  amount of product processed and the volume of generated
wastewater which must be treated.

OYSTER WASTEWATER

The shrimp wastewater DAF treatment  system was utilized to treat wastewaters from oyster
processing and canning  for a  four week period  in early 1977.  Flow rates were about one
fourth as great as while processing shrimp.  Screened oyster wastewaters contained higher
suspended solids and lower concentrations of oil and grease and biochemical oxygen de-
mand.  Mean values were: BODS - 510 mg/l;  O & G - 37 mg/l; TSS  -  2,280 mg/l and
settleable solids - 30 ml/1.

Operating without pH adjustment but with alum and polymer as coagulants, the DAF sys-
tem designed for shrimp cannery wastewater treatment was effective in reducing the dis-
charged pollutants. Mean percentage removals attained were: BODS - 43%;  O & G -
56%; TSS - 89%;  Settleable Solids - 99%.

SUMMARY

It may be concluded from  this study that dissolved air flotation physical-chemical treat-
ment of shrimp processing  and oyster processing wastewaters can be effective in reducing
conventional pollutants.  Such a pollution abatement-treatment system for shrimp process-
ors should include a program  of water  use and wastewater management, pre-screening, a
recycle mode dissolved air flotation system with automated pH control, proportional coag-
ulant and coagulant aid feeders, and a suitable solids handling system.  An effective,
satisfactory method of collecting, concentrating, storing,  handling and  disposing of
screenings and skimmings solids is yet  to be developed and now appears to be a major
detriment to the effective operation of the DAF treatment system on shrimp processing
wastewaters.
                                        229

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                                   REFERENCES
1.  Mauldin, A.F., and Szabo, A. J., Shrimp Canning Waste Treatment Study,
    U.S.  EPA - 660/2 - 74 - 016, June 1974.

2.  Ertz,  D.B., Atwell,  J.S.,  and Forsht,  E.H., "Dissolved Air Flotation Treatment
    of Seafood  FYocessing Wastes - An Assessment", Eighth  National Symposium on
    Food Processing Wastes,  Seattle,  Washington, 1977.
                                      230

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                            UPGRADING A BREWERY
                    WASTEWATER PRETREATMENT FACILITY FOR
                         THE CITY OF WINSTON-SALEM

                                      by

               C.D. Malone*, R.M. Stein*, and T.D. Cornett**
INTRODUCTION

The malt beverage brewing industry produces in excess of 60 bil gal of waste-
water annually.  A large percentage of this wastewater discharges into munici-
pal wastewater treatment facilities.  Typical raw waste loads for the malt
beverage brewing industries are presented in Table 1.  The quantity of oxygen
demanding materials and suspended solids generated requires a high level of
treatment.  This treatment is normally provided either at the brewery or at
a municipal wastewater treatment plant.  This paper reviews the treatment
system and operation program developed by the City of Winston-Salem, North
Carolina, for treatment of a brewery wastewater at the Archie Elledge Waste
Treatment facility.  The City of Winston-Salem operates a 36 mgd activated
sludge waste treatment plant.  The treatment plant provides both primary
and secondary treatment.  Primary treatment consists of bar screens, grit
removal, and primary clarification; while secondary treatment consists of
four 200-ft diameter trickling filters followed by activated sludge and
chlorination.  Excess biological and raw primary sludges are anaerobically
digested and subsequently dewatered on sand drying beds.  The dried sludge
is applied directly to farm lands.  Gas produced by anaerobic digestion
of the sludges is utilized to generate all electrical power requirements.
Figure 1 presents a schematic illustration of the Archie Elledge Waste
Treatment Plant.

Operational problems were experienced at the Archie Elledge plant, because
of an organic overloading of the secondary treatment system.  The City and
and its consultant, AWARE, Inc., evaluated alternatives to reduce the organic
load to the secondary treatment facilities.  The results of this evaluation
indicated that pretreatment of the brewery waste was the most practical
approach to the problem.  Pretreatment of the brewery waste was selected for
two major reasons.

     1.    The City of Winston-Salem has a number of industries which dis-
          charge concentrated wastes into the treatment system.  Most indus-
          trial wastes are combined with domestic waste and diluted before
          reaching the treatment plant.  The brewery waste discharges into
          a separate outfall with only 100 private residences and thus
          arrives at the treatment plant without significant dilution.
          Thus, the brewery waste was segregated and arrived at the plant
          as a concentrated stream.


*Associated Water and Air Resources Engineers, Inc., Nashville, Tennessee
**City of Winston-Salem, Winston-Salem, North Carolina


                                    231

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	PRE-TREATMENT
-f-
                                                	PRIMARY TREATMENT
                                                                                                   -SLUDGE HANDLING FACILITY
     lnl«fc«plor
      S«w«r
                                                                                                PRIMARY  SECONDARY    SLUDGE
                                                                                                DIGESTER DIGESTER      DRYING
                                                                                                                     BED
                                                                                                                                To Dupowl
                              FINAL CLARIFIERS
                                                        ACTIVATED SLUDGE
                                                           BASINS
                                                                              NTERMEDtATE CLARIFIERS
                                                                                         —OSompling LocoHofl
                                                                                         	UtaNMMr Floo
                                                                                         	Slud0« Flow
                                                               - SECONDARY TREATMENT
                    FIG.  I . SCHEMATIC ILLUSTRATION OF THE  MUNICIPAL WASTE  TREATMENT PLANT

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                TABLE  1.  TYPICAL RAW WASTE CHARACTERISTICS
                       FROM MALT BEVERAGE PRODUCTION
                                                         Brewing Industry
                                                       Mean Raw Waste Loads
                                  Average Range          per Bbl of Beerc

Raw Waste Volume                 2649,5-30280 m3         971o46£/bbl beerb

Raw Waste BOD                    1400-2000 mg/ia         1.37 kg/bbl beerb
Raw Waste Suspended Solids        500-700 mg/la           .56 kg/bbl beer
 (1622 mg/i)

> kg/bbl be<
 (772 mg/1)
 federal Guidelines, State and Local Pretreatment Guidelines, Construction
 Grants Program Information, EPA-430/9-76-017c, January  19770

 EPA Technology Transfer  Series, Capsule Report 6, Pollution Abatement in
 a Brewing Facility.,  Prepared by U0S0 EPA0

 C0ne barrel contains 117„18 liters.
     2.   The potential for developing filamentous organisms could be re-
          duced by pretreatment of a predominatly carbohydrate brewery
          waste prior to the activated sludge system.

Table 2 presents a summary of the brewery raw wastewater characteristics
as it enters the Elledge plant.  This discharge includes the brewery, the
brewery container manufacturing plant wastes, and a small domestic con-
tribution.  The brewery wastestream comprises approximately 35 percent of
the total BOD loading to the waste treatment plant and approximately 10 per-
cent of the total plant flow.

The pretreatment system was developed in two phases.  The initial phase of
the brewery pretreatment facilities, constructed in 1971, consisted of a
1.33 mil gal aerated lagoon with an installed horsepower level of 360.
The system was designed to treat a flow of 2.5 mgd.  The effluent soluble
BOD from the basin averaged 450 mg/1 with a volatile suspended solids
level of approximately 850 mg/1.

In 1977, it was decided to expand and upgrade the pretreatment facilities
to accommodate the increased loadings and produce an effluent with a solu-
ble BOD level of less than 350 mg/1.  Discussions with brewery personnel
indicated that with increases in production and expansion of the brewery
facilities, the average brewery wastewater flow could be expected to be
3.5 mgd with a BOD concentration of approximately 2,000 mg/1.
                                     233

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          TABLE 2.  SUMMARY OF BREWERY RAW WASTEWATER CHARACTERISTICS
(a)
Parameter
Min.
BOD 1,011
SS 269
TKN
NH -N 4.1
3
NO -N 3.8
ALK 395
pH, units 5.7
1976
Avg.
1,509
546
Monthly
Average Values
1977
Max.
2,103
739
Min.
945
361
20
(c)

(c)
(c)

4.

3.
2

9
405
6.
9
(c)

(c)
(c)

4.

4.
3

1
414
7.
4
(c)

(c)
(c)

1.

0.
4

4
209
6.
9
Avg.
1,378
526
27.8
4.4

3.0
320
7.5
Max
1,777
773
46
12

15.5
402
7.7
  o
   All units are mg/1 except as noted.

   Expressed as mg/1 of C^CO .
                         ^  o
  f*
   Data shown for November 1976 and December 1976 only.
Prior to upgrading the treatment facilities, the operation of the existing
pretreatment system was reviewed.  The objective of. this review was to
define problems in the operation of the brewery pretreatment system so
that solutions to these problems could be incorporated in the upgraded
facility.  A discussion of some of the operational problems associated
with the treatment of brewery wastewaters is presented as follows.

OPERATIONAL CONSIDERATIONS

Significant variations in both the quantity and quality of brewery waste-
waters result because of batch processing and the seasonal fluctuations
in production schedules.  Figure 2 presents the chronological variations
of the average monthly BOD and suspended solids loading to the Elledge
treatment plant from the brewing facilities.  Peak production, as noted
by increased loadings to the plant, was during April through August,
which is consistent with historical data.  These seasonal variations are
significant in the operation of waste treatment facilities from the stand-
point of:
                                    234

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             Q
             UJ
             Q
             Z
             UJ
             O.
                 9,000
                  5,000
             1 - 1
                                                                                1 - h
t-0
U)
Ul
             I
              M
             Q
             §
                 20,000
                 10,000
                                         M
M
j       J
  1976
O
                                                                                             N     D
                                       FIG. 2 MONTHLY VARIATION OF BREWERY WASTELOAD

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      1.    Equalization must be provided or the facility  must  be  suffi-
           ciently large to accommodate the peak loadings.

      2.    The high loadings increase  oxygen demand  on  the  treatment sys-
           tem during the summer months.

 Significant  diurnal load variations are found  in the brewery  wastewater.
 Figure 3  presents the diurnal variation in chemical oxygen demand  (COD)
 observed  over a  48-hour period.   The  diurnal variations  of COD during
 this  particular  period ranged from 1,100 mg/1  to 2,600 mg/1.  Figure 4
 shows typical diurnal flow patterns from the brewery.  Extreme diurnal
 variations of pH are experienced due  to the batch operation of the brewing
 process and  the  necessity of thoroughly cleansing the  equipment with caus-
 tic wash  solutions between brews.  Figure 5 shows typical  variations of
 the wastewater pH during a 24-hr period and indicates  the  severity and
 duration  of  the  pH oscillations.

 The wastewater as received from the brewery does not contain  a sufficient
 quantity  of  nitrogen to accommodate biological oxidation.  It is, there-
 fore,  necessary  to supply a supplemental nitrogen source to meet the
 nutrient  requirements  of the microorganisms.   Liquid agricultural nitrogen
 (30 percent  total nitrogen content) is  purchased and metered  into the
 aeration  basin.   The cost of the nitrogen supplement amounts  to approxi-
 mately $36,000 per year.   The varying  organic  load  of  the  brewery waste-
 stream requires  constant monitoring of  the  nitrogen addition  facilities
 to ensure that an adequate nitrogen level is maintained.

 Problems  have  been experienced because  of excessive discharges into the
 treatment system.   Three major organic  discharges including dextrose and
 corn  syrup have  occurred at the  brewery  because  of  equipment malfunctions
 and ruptured pipes.  The largest  of the  discharges  resulted in approxi-
 mately 22,500  kg  of  dextrose entering  the treatment facility.  This organic
 load  to the  aeration basin caused a rapid depletion of the dissolved oxygen
 level  in  the pretreatment basin  and subsequent reduction of treatment
 efficiency.  This  resulted in high organic  loads being transferred to the
 plant proper with  an ultimate deterioration of final effluent quality.
 It took approximately  three days  for the system to  recover from this shock.

 The discharge  of  oil and grease  into the collection system is another pro-
 blem.  The oil and grease originate from the metal  cans manufacturing faci-
 lity.  Although  no inhibitions to  the biological systems have been observed
 due to the oil and grease spills,  fouling of the collection system and
 pumping facilities has occurred.   This results in a large  manpower expendi-
 ture  in cleaning  the transport facilities.

A frequently occurring  problem encountered  in  the treatment of brewery
wastewaters  is that  of  foam on the aeration basins.  Foam  layers 4-5 in.
 deep have formed  on  the  aeration  basins  and this is undesirable for several
 reasons.  The  foam rises  and flows out  and  onto  the ground surrounding the
basins.   The bio  solids  become entrapped in the  foam and are also carried
 out of the basin.   This  causes unsafe conditions  and presents a potential
odor problem.  Additionally,  if  the foam does  not overflow the basins, the


                                    236

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U)
•-J
   3,000



   2,500



   2,000



O  1,500



   1,000



     500
                 1
                              12am  5am   10am   3pm   8pm
                                         2-24-76
                                             lam   6am   11am  4pm    9pm
2am
                                                            2-25-76
                                                          TIME, hours
                            FIG. 3 TYPICAL DIURNAL VARIATIONS OF BREWERY WASTEWATER COD

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                                   NOTE: EACH UNIT ON THE GRAPH
                                   REPRESENTS 1mgd
FIG. 4  TYPICAL DAILY FLOW PATTERNS FROM THE BREWERY
                            238

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FIG. 5 TYPICAL DIURNAL pH VARIATIONS
                 239

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 solids have a tendency to accumulate and form crust layers  on top  of  the
 foam,  again resulting in odor problems.

 SIGNIFICANT DESIGN CONSIDERATIONS

 Increased loadings on the Elledge treatment  plant  again  overloaded in
 the  plant in 1976  ; therefore,  it was decided to expand the  brewery pre-
 treatment process.   This  would  relieve the plant of the  increased  brewery
 loadings  and allow the plant  to receive and  accommodate  increased  loads
 from other industrial contributors.   The objectives in upgrading the
 brewery pretreatment system were:

     1.    To reduce the incoming organic waste  load from the  brewery.

     2.    To provide capabilities within the system to dampen and  equalize
           the quantity and  quality of  the brewery  wastewaters.

     3.    To include the  flexibility of  operating  the two-basin system
           in either a series or parallel mode.

     4.    To examine the  feasibility of  utilizing  anaerobic digester
           supernatant as a  nitrogen  source.

Pilot aerated lagoon  studies were performed  and  full-scale operating
data were  evaluated to  develop  the process design  criteria and the use
of digester  supernatant as  a nitrogen  source.  The results of  these studies
are summarized in Table 3.  Table 4  presents  the average characteristics
of the digester supernatant.  The results of  the studies indicated that an
aerated lagoon could  provide high levels  of  organic removal.  The digester
supernatant  proved  an effective nutrient  source.   An effluent soluble BOD
of less than 350 mg/1 could consistently be  achieved with the addition of
digester supernatant.


  TABLE 4.   SUMMARY OF  ANAEROBIC DIGESTER SUPERNATANT CHARACTERISTICS
                  ARCHIE ELLEDGE WASTE TREATMENT PLANT
Parameter
COD, total (mg/1)
Solids (percent)
Volatile Solids (percent)
NH3-N (mg/1)
3
Flow m
Value
14,891
1.70
0.80
245.
946.25
                                    240

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                                                            TABLE  3




                                               SUMMARY OF  PILOT PLANT  PERFORMANCE
Parameter

BOD, total
BOD, soluble
COD, total
COD, soluble
SS
VSS
SS (ZSV Supernatant)
VSS (ZSV Supernatant)
TKN, total
TKN, soluble
NII3-N
pll (units)
MI.SS
MLVSS
1). T. days
0 Uptake, (mg/1 - min)
Temperature, °C
F/M (g/BOD/g MLVSS - day)
D.O.
Averaging Period
Value
Unit I(b)
Influent Basin Effluent
839 259
613 45
1,269 1,055
1,032 183
559 761
253 419
373
265
55
--
19 23
7.3 8.0" 7.9
872
513
1.21
0.28
20
1.35
5.4
2/1 to 23/77
(a)
Influent
839
613
1,269
1,032
559
253
—
--
55
--
19
7.3







Unit II(c)
Basin Effluent
198
23
857
167
807
475
188
133
—
—
26
8.1 7.9
863
516
2.31
0.23
20
0.70
5.4
2/1 to 23/77
Unit III(d)
Influent Basin Effluent
2,228 753
.1,267 220
5,580 2,606
2,063 467
3,200 2,435
1,878 1,337
367
240
213 31
29.5
45 13
7.0 7.8 7.8
3,348
] ,966
1.10
0.41
20
1.03
3.0
3/1 to 15/77
Unit IV(e^
Influent Basin Effluent
2,370 824
1,165 76
4,870 3,419
1,975 295
4,278 4,185
2,030 2,544
265
86
279
22
55 16
7.1 7.8 7.9
4,641
2,673
0.99
0.29
20
0.90
3.2
3/1 to 15/77
a)  All units aie mg/1 except as shown, d)  Unit at one day detention  time, with P percent supernatant  (based on influent flow).



b)  Unit at one-day detention time.     e)  Unit at one-day detention  time, with 13 percent supernatant  (based on  Influent flow).



c)  Unit at two-days detention time.

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 Tests were  conducted  to  determine  the  rate  of oxygen  transfer  into the
 brewery  wastewater  relative  to  the oxygen transfer rate into tap water
 (alpha tests).   Several  series  of  alpha  tests were performed through
 the  course  of  the study.  These results  are summarized in Table 5.  These
 values,  0.6 to  0.7, are  considered reasonable and were used for design.


                 TABLE 5.   SUMMARY  OF OXYGEN TRANSFER  ANALYSES
Sample Location
and Date
Basin Effluent
(March 1976)
Basin Effluent
(March 1977)
Basin Influent
(March 1977)
Test Speed
RPM
150
225
300
100
200
288
100
200
288
(a)
Alpha Factor '
0.52
0.15
0.33
0.66
0.67
0.64
0.48
0.56
0.58
   All values  corrected  to  20°C.
The microorganisms utilize oxygen for biological respiration.  For brewery
waste treatment,  (approximately 2.0 to 5.0 g 0~/g basin volatile solids-day
is required).  This is very high when compared to rates for a typical acti-
vated sludge system of between 0.1 to 0.8 g 0,,/g basin volatile solids-day.

These two factors, low transfer rates and high oxygen uptake rates, result
in a large horsepower input to the basin, approximately 270 hp/mil gal of
basin volume.  Typical activated sludge horsepower levels range from 100 to
150 hp/mil gal of basin volume.

DESIGN CONSIDERATIONS FOR OPERATIONAL FLEXIBILITY

Utilizing the results from the bench-scale tests, and data gathered from
the operation of the full-scale system, a process design was developed for
the proposed expansion.  The design summary for the expanded facilities is
presented in Table 6.

Figure 6 presents a schematic illustration of the expanded facilities
employed for the pretreatment of the brewery wastewaters.  Basin 1 was
first placed on line in 1971 and Basin 2 was put into service in October
1977.  Total installed horsepower for both basins is 900.
                                    242

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                 ANAEROBIC

                SUPERNATANT
                                                                     c
                                                                                          EFFLUENT
                                                                                           SAMPLE
                                                                                            POINT
    LIQUID
   NITROGEN
         INFLUENT
         SAMPLE
         POINT
  FROM
BREWERY
          HOUSE
    FLOW
PROPORTIONED
 SPLITTER BOX
                                                         BASIN 1
                                                      VOL  = 5,034m3
                                                      HP
                                        = 360
                                                         T
                                                             BASIN 2
                                                         VOL  = 8,327m3
                                                                             VARIABLE
                                                                              LEVEL
                                                                             WEIR BOX
                        FIG. 6  SCHEMATIC ILLUSTRATION OF BREWERY PRETREATMENT FACILITIES

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                          TABLE 6.  DESIGN SUMMARY
          Parameter                                    Value

     AERATED LAGOON

       Design Flow, m3                                13,247.5

       Influent BOD, mg/1                              2,000

       Effluent BOD, mg/1                               350
                      3
       Basin Volume, m

            Existing Basin                             5,034.05
            New Basin                                   7,570
       Aeration Horsepower, hp

            Existing Basin                               360
            New Basin                                    540
       Surge Capacity, m

            Existing Basin                                0
            New Basin                                  2,460.25

       Nitrogen Requirements,  kg/day
            Maximum                                     1,314
            Average                                     1,026
The problem of fluctuating wastewater flow and load was addressed in the
process design.  Approximately 0.65 mil gal of surge capacity was incor-
porated into the design of the new basin.  The surge capacity calcula-
tions were predicated on providing additional equalization for the acti-
vated sludge basin in the plant proper.  The surge capacity was achieved
by constructing a variable level discharge weir in the new basin.  Using^
high-speed, floating aerators allows the water level to be varied approxi-
mately 2.5 feet (0.65 mg).

In the design of the new facilities, flexibility was incorporated to allow
the operation of the two basins in either a parallel or series mode.
Basin 1 is operated on a flow-through basis, while Basin 2 can be operated
at varying levels.

It was decided to utilize digester supernatant as a nitrogen source.  Uti-
lizing the digester supernatant offers several advantages.  The need to
purchase ammonia was eliminated resulting in a $35,000/yr savings.  The
supernatant characteristically has pH in the range of 6.5 to 6.8.  This
slightly acidic pH coupled with an alkalinity value of approximately
2,000 mg/1, as CaC03, helps to buffer the fluctuating pH received from

                                    244

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the brewery.  Additionally, the basin alkalinity as CaCO,. has increased from
approximately 225 mg/1 to approximately 450 mg/1.  This affords a much
greater degree of protection from pH upsets.  A pumping station was con-
structed and attendant piping installed (approximately 1,080 m at 20-cm
diameters).

The causes of foaming were evaluated and it was determined that the
foaming phenomenon results because of:

     1.   The high agitation levels within the basin (approximately
          270 hp/mil gal.

     2.   Large volume of caustic wash solutions used at the brewery.

     3.   The foaming nature of the beer product itself.  Operating
          experience has found that the foam can best be controlled
          with the use of commercially available defearning agents.

The problem of oil and grease discharges was resolved through the coopera-
tion of both the City and the brewery.  The brewery has implemented pre-
treatment to capture oils.

TREATMENT PLANT PERFORMANCE

The new basin has been on stream since October 1977.  Several mechanical
difficulties prevented full-scale operation prior to February 1978.  The
first several weeks of operation are encouraging.  Figure 7 presents a
chronological summary of various operational parameters.  These data indi-
cate that the basin is consistently producing an effluent with a soluble
BOD level of less than 350 mg/1.  Normally, effluent soluble BOD is in
the range of 200 mg/1.  These data reflect parallel operations of the two
basins.  Operation in a series mode has not been initiated.

The treatment of brewery wastewaters in a municipal waste treatment plant
presents some particular problems that must be addressed through design
and operation of the facility.  The City of Winston-Salem has addressed
this problem and has developed a program to successfully treat brewery
wastes.
                                     245

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          BEGAN ADDING DIGESTER
              SUPERNATANT
                            17
                              2    7    12
           FEB                       MARCH
FIG. 7 CHRONOLOGICAL VARIATION OF PRETREATMENT
            SYSTEM PERFORMANCE
246

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                    PHOSPHORUS REMOVAL AND DISINFECTION
                      OF MEAT PACKING LAGOON EFFLUENT

                                    by

                Richard T. Beaupre'* and Milton D. Redick*
 INTRODUCTION
In order to  comply with EPA and the State of Michigan wastewater effluent
limitations,  the Feet Packing Company of Chesaning, Michigan, contracted with
Capitol Consultants, Inc., of Lansing, Michigan, for an engineering study to
determine alternatives for the upgrading of existing anaerobic-aerobic lagoon
facilities.

Preliminary  design basis and cost estimates were generated for seven alter-
natives for  additional BOD, SS, ammonia, and phosphorus removal as well as
disinfection.  Based on modified discharge requirements by the Michigan
Department of Natural Resources, it was decided to proceed with design and
construction  of phosphorus removal and disinfection facilities.  Phosphorus
removal is to be attained with chemical addition and clarification.  Due to
high ammonia  levels of the wastewater, disinfection with chlorine dioxide
was chosen in order to reduce chlorine demand and to reduce the formation of
potentially harmful chlorine compounds.  Construction of the facility is
nearing completion at this time.
BACKGROUND

The Peet Packing Company, Chesaning, Michigan, is a meat processing plant
which slaughters and processes an average of 1,050 hogs a day into fresh and
smoked meat products.  The current employment at the plant is approximately
400 persons.  The plant is located just north of the Village limits of
Chesaning, Michigan, and adjacent to the Shiawassee River, a tributary to
Lake Huron.

The principal meat products at the plant are fresh and smoked hams, sausages,
and luncheon meats.  Raw beef is purchased from outside sources for inclusion
in these products.  Additional daily processes are the rendering of fat into
edible lard, and the drying of blood into an agricultural product.  By-
products consisting of all hog-viscera, condemned carcasses, parts of bones,
and lard rendering refuse are shipped to an independent Tenderer.  Hair and
holding pen manure are also hauled from the plant.
*Capitol Consultants, Engineers, Inc., Lansing, Michigan


                                     247

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 The  wastewater  from Peet Packing  Company varies greatly in both volume and
 character  throughout a normal  operating day.  Major wastewater streams are
 hog  and  carcass  rinse water  from  the kill  floor, chill sprays from the cut
 floor, scald  tank  dumping, sanitary sewage, boiler blow-down, compressor
 cooling  water,  and plant cleanup  chemicals and water.  The majority of blood
 is captured during the sticking operation  and pumped to a dryer.  The steam
 condensate from the dryer  contains blood residue which also adds to the
 wastewater strength.

 Original Wastewater Treatment  Facilities

 The  original wastewater treatment facilities consisted of an anaerobic and
 two  aerobic ponds  operated in  series and with continuous discharge.  The
 ponds were constructed in 1967 and designed on an expected BODs loading of
 750  kg (1,650 Ibs.)  per day  and a flow of  1,285 m3/d (340,000 gpd)(1).  The
 plant currently  discharges approximately 640 m /d (170,000 gpd) to the
 Shiawassee River in South Central Michigan.

 Raw  wastewater  is  collected  at a  large sump and pumped to the anaerobic
 lagoon,  a  distance of approximately 245 m  (800 feet).  The lagoon is a clay
 lined 3.7  m (12  feet) deep pond, with dimensions at the surface of 46 x 46 m
 (150 x 150 feet),  and with walls sloped 2  horizontal to 1 vertical.  The
 volume of  the pond is 3,855  m3 (1,020,000  gal.); at a plant flow of 640 m3/d
 (170,000 gpd), the average detention time  is 6 days.  A heavy layer of fat
 and  scum accumulates  on the  pond surface and maintains anaerobic conditions;
 the  layer  also helps  control odor and heat loss.  The anaerobic lagoon has
 two withdrawal pipes which empty to a wet well pumping station through a
 siphon which maintains a constant pond depth.  Wastewater is pumped from the
 station a  distance of 660 m  (2,180 feet) to the aerobic lagoons.

 The  aerobic lagoons  are 1.5 m  (5 feet) deep clay lined ponds with a total
 surface area of  5.9 hectares (14.3 acres).  The walls have a slope of 3
 horizontal to 1  vertical; freeboard at a 1.5 m (5 foot) depth is 0.9 m (3
 feet).  The volume of the ponds is 83,000 m3 (22,000,000 gal.); the average
 detention  time at  a plant flow of 640 m3/d (170,000 gpd) is 130 days.  The
 aerobic ponds were designed  for an average BOD5 loading of 33.6 kg/hectare/
 day  (30 Ibs./acre/day), or 196 kg/day (430 Ibs./day).  Wastewater from the
 aerobic ponds flows by gravity a distance  of 460 m (1,500 feet) to the
 Shiawassee River.

Lagoon Treatment Efficiencies

Table 1 is a summary of testing data from  1973 through 1977.  Raw wastewater
samples,  composited during the slaughtering operation, were collected by
Peet Packing and tested for BOD5 once a week from 1969 through July of 1975.
The results of these tests vary widely from BODs's of 800 mg/1 to over
 10,000 mg/1.   Raw wastewater sampling is very difficult, however, in that
 large pieces of  fat or tissue cannot adequately be accounted for, nor do grab
samples account  for lower flows and strength during non-slaughtering hours
and weekends.   The figure of 2,000 mg/1 is the best estimate of the overall
average weekly raw wastewater strength.
                                     248

-------
Grab samples of anaerobic lagoon effluent were also tested on a weekly basis
by Peet Packing.  This data showed the lagoon effluent BOD5 to normally vary
from 150 mg/1 to 700 mg/1, with peaks of up to 6,700 mg/1 when the blood
dryer was not in operation.  The temperature of the effluent varies between
29° C. (85° F.) in the summer and 14° C. (57° F.) in the winter.  The pH
varies from 6.3 to 7.5 with most readings below 7.2.  The data collected
indicates a typical reduction in BOD5 of from 80% to 85% through the
anaerobic lagoon.  References (2), (3), and (4) show typical removal rates
of 80% at other meat packing anaerobic lagoons.  Of significant importance
is the increase in ammonia content over the raw wastewater due to the decom-
position of meat pieces and the conversion of organic nitrogen.

The aerobic lagoon effluent quality has been defined by weekly sampling of
BOD5 prior to 1975, and in addition, weekly sampling of suspended solids,
total phosphorus, ammonia as N, and oil and grease since that time.  The
data shown in Table 1 are presented in time periods to demonstrate the
influence of periods of shut-down of the blood dryer and the freezing over
of the aerobic lagoons.  During periods of blood dryer shut-down all blood
is included in the wastewater stream and lagoon loadings are increased by a
factor of ten.  In order to alleviate this large overloading, the company
has recently made provisions to haul blood from the plant when the dryer
requires repair.  Figure 1 is a plot of average monthly BOD5 and the data
indicates a significant deterioration of quality during winter months; how-
ever, during all of the past winters, the blood dryer has not been in
operation for periods of up to a month, and during January and February of
1975, the anaerobic lagoon was dredged out.  Thus the freezing of the ponds
appears to have a significant influence on 8005; however, the extent is not
known.

The aerobic ponds have typically produced a BOD5 reduction of from 60-90%,
with the 90% rates occurring when the ponds were at normal loadings of 34
kg/ha/day (30 Ibs./acre/day) or less.  The overall average loading of the
aerobic ponds, however, has been 40 kg/ha/day (36 Ibs./acre/day) with peaks
up to 740 kg/ha/day (660 Ibs./acre/day) when the blood dryer was shut-down.
In addition to hauling blood when it cannot be dried, the plant has also
been attempting to install a hydrasieve screen to eliminate pond over-
loading.   The six month period of from June, 1976 to December, 1976, illus-
trates an average final effluent quality of 38 mg/1 BOD5 and 70 mg/1 S.S. is
achievable.  These concentrations would result in an average discharge to
the River of 25 kg/day (54 Ibs./day) BOD5 and 45 kg/day (99 Ibs./day) S.S.
at 640 m3/d (170,000 gpd).

Figure 2 is a plot of average monthly phosphorus concentration based on
weekly sampling, and fecal coliform counts based on monthly sampling.  The
average monthly phosphorus concentrations follow a nearly identical pattern
as the effluent BOD5 shown in Figure 1, except with a less dramatic varia-
tion.  The variation in phosphorus may, however, be due to algae uptake and
release.   Fecal coliform counts have been below the required July 1, 1977
NPDES permit levels much of the time, but appear to jump higher coinciden-
tally with the blood evaporator shut-down and initial heavy BOD discharge.
                                     249

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                                   TABLE 1
                     SUMMARY OF WASTEWATER QUALITY DATA
                           JULY, 1973 TO MAY,  1977
                  PEET PACKING COMPANY,  CHESANING, MICHIGAN
  Sample

 Raw
 Waste-
 water

 Anaerobic
 Lagoon
 Effluent

 Aerobic
 Lagoon
 Effluent
 Sampling
  Period
7/73-7/75
7/73-7/75
8/75-12/75
1/76-5/76
6/76-12/76
1/77-5/77
BOD5
mg/1
7/73-7/75    2,000
  360
  163
   36
  182
   38
  251
 81
101
 70
102
                        Fecal
       Phos.   NH3    Coliform      Flow
       mg/1    mg/1   f/100 ml   m3/d  mgd

        19*     7*
        25*    55*
25*
16
24
21
32
55*
61
75
48
69
2,400**
800
2,900
300
40
720
680
640
490
640
0.19
0.18
0.17
0.13
0.17
Fecal Coliform  Samples:   1 grab per month
Remaining Samples:   1 grab per week

 *0ne sample.
**Five samples.
Effluent Limitations

The effluent limitations for the Peet Packing Company were determined based
on the most stringent of two criteria:  the water quality standards of the
Michigan Department of Natural Resources and the EPA "Meat Products Point
Source Category Effluent Guidelines and Standards"(5).  The Peet Packing
Company is categorized as a "High-Processing Packinghouse".  The water
quality standards require an average 8005 of less than 36 kg/day (80 Ibs./
day) and 80% phosphorus removal; EPA limitations based on LWK (live weight
killed) resulted in limitations of 3005 of less than 36 kg/day (80 Ibs./
day), T.S.S. of less than 46.9 kg/day (104 Ibs./day), fecal coliform counts
of less than 400/100 ml, and oil and grease of less than 20 kg/day (44 Ibs./
day) with daily maximum limits less than twice that of the average.  The
original effluent limitations also included a maximum ammonia discharge of
8 mg/1 during the period May 1 through October 31, with a pH limitation
between 6.0 and 7.5.  The ammonia limitation was later dropped by the
Michigan DNR.
                                    250

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                                                                                                     ru
                                                                                       1977 PERMIT LEVEL

                                                                                       80**/DAY

                                                                                       36 KG. / DAY
                                                                                    CO
                                                                                    CD
                                                                                                                  Q
                                                                                                                  O
                                                                                                                  m
                                                                                                                     600
                                                                                                                     500
                                                                                                                     400
                                                                                                                     300
                                                                                                                     200
                                                                                                                     100
         23456789


                  1974
10  II  12  I   2  3  4 5  6  7 8  9  10


                    1975
                                                      12  I  23456789  10 II  12 I   234567

                                                                     1976                            1977
                                     Figure 1.  BOD5 of anaerobic lagoon effluent.

-------
to
                                                  FECAL COLIFORM
                                                       AVERAGE MONTHY
                                                       PHOSPHORUS
                                                       CONCENTRATION
                                                       1977  FECAL COLIFORM
                                                       PERMIT LEVEL
                                                       400/100  ML
                             8  9  10 II  12  I  2  3 4  5  6  7  8  9  10 ,11  12  I  2345678
                                                                                            - 4000
                                                                                              3000  g
                                                                                                    oc
                                                                                                    £
                                                                                            - 2000
                                                                                                    o
                                                                                                    u
                                                                                                    o
                                                                                                    LU
- 1000
                          Figure  2.   Fecal coliform and phosphorus of  aerobic  lagoon effluent.

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WASTEWATER TREATMENT ALTERNATIVES EVALUATED

Preliminary design basis and cost estimates were generated for seven alter-
natives for upgrading the anaerobic-aerobic lagoons at the Peet Packing
Company.  The alternatives were to provide additional BOD, S.S., ammonia,
and phosphorus removal, as well as disinfection.  All of the alternatives
evaluated utilized biological treatment for BOD, S.S. and ammonia removal.
The most severe limitation for treating the wastewater was the ammonia
removal requirement.  Ammonia can be converted to nitrate by nitrifying
organisms but their activity is hindered by low temperature and substantial
BOD reduction must take place prior to their becoming effective(6).

The first four alternatives included complete treatment at the Peet Packing
Company utilizing the existing anaerobic lagoon with the aerobic lagoons
used as a backup system.  Additional biological treatment after the aerobic
lagoons was not considered because it was felt the very low discharge
temperatures of 2° C. (35° F.) during the winter and 7° C. (45° F.)  during
April would inhibit establishment of ammonia removal prior to the May 1st
requirement.  The fifth alternative considered pretreatment following the
anaerobic lagoon with discharge to the Village of Chesaning Municipal
Wastewater Treatment Facility.

The design basis for treatment after the anaerobic lagoon was as follows:

                     Flow         1,134 m3/d (0.3 mgd)
                     D.O.             0 mg/1
                     BOD5           500 mg/1
                     S.S.           300 mg/1
                     NH3-N           50 mg/1
                     P               25 mg/1

The sixth and seventh alternatives were to utilize both the anaerobic lagoon
and aerobic lagoons.  The sixth alternative was to provide additional
storage for intermittent discharge during the winter months only, when river
flows are greater and 80% ammonia removal was required, rather than removal
to a level of 8 mg/1.  The seventh alternative was land application with
border strip irrigation.

The major design parameters, capital cost and annual cost for each of the
alternatives are summarized as follows.  The capital cost estimates were
for 1976, and include engineering and contingencies.  The annual cost esti-
mates include amortization of the capital cost at 8% interest over 20 years,
labor, power, chemicals, testing, sludge handling and maintenance.
                                     253

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 Alternative 1 —  Rotating  Biological Disc

 This  system required  55,800 m2  (600,000 ft.2) of media on 6 shafts, six 5 HP
 drives,  fiberglass  covers for the  shafts, a pre-aeration basin with 4 hours
 detention time to restore D.O.,  a  clarifier, a  chlorine contact chamber, an
 aerobic  sludge digester,  and a  control building with chemical storage.  Some
 of  the advantages of  a  rotating  disc  system are low power cost, ease of
 operation and low maintenance cost.   The total  estimated cost of the system
 was $767,000, with  a  total annual  cost of $136,200.

 Alternative 2 -  Extended  Aeration  Activated Sludge

 An  extended aeration  system required  a 2,270 m^ (600,000 gal.) circular
 aeration basin,  three 50  HP compressors, two clarifiers, a chlorine contact
 chamber,  an aerobic sludge digester,  and a control building with chemical
 storage.   The aeration  unit required  48 hours detention time and a solids
 retention time greater  than 10 days in order to achieve nitrification.  In
 order to  achieve long solids retention times, a high solids recycle was
 required  for  the first  clarifier which would not be conducive for phosphorus
 removal.   Therefore,  a  separate  clarifier was proposed for phosphorus pre-
 cipitant  settling.  A dome cover was  also proposed to minimize heat loss
 and control odor problems.  The  total estimated cost of the system was
 $769,600,  with a total  annual cost of $156,500.

 Alternative 3 - Oxidation Ditch

 An oxidation  ditch  system required a  2,840 m^ (750,000 gal.) looped trape-
 zoidal channel, two 5.5 m (18 foot) long rotor  aerators with a 30 HP drive
 for each,  two clarifiers,  a chlorine  contact chamber, an aerobic sludge
 digester  and a control building with  chemical storage.  The oxidation ditch
was to provide a minimum  of 48 hours  detention  time and 10 days solids
 retention time.   The  advantage of  the oxidation ditch system was a lower
 capital cost and ease of  maintenance; however,  odor control would be more
difficult,  and lower wastewater  temperatures would result.  The total esti-
mated cost  of the system was $590,000, with a total annual cost of $118,200.

Alternative 4 - Pure Oxygen Activated Sludge

A pure oxygen system required a  closed chamber, 15 m (50 feet) square and
3-5 m (10-16 feet) deep,  containing a BOD5 removal cell with a 7-1/2 HP
mixer, a  clarification cell, an  ammonia removal cell with a 5 HP mixer, and
a second  clarification cell for  phosphorus removal.  The system also
required  a  pre-aeration tank, an aerobic digester, a chlorine contact
chamber,   and a control building with  chemical storage.  Pure oxygen would
be supplied from a liquid  oxygen storage tank which would require filling
every 2 months by a truck  delivery.   The major  advantage of a pure oxygen
system is  the limited space required.  The total estimated cost of the
system was  $764,600, with  a total  annual cost of $158,100.
                                     254

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Alternative 5 - Pretreat and Discharge to Municipal Wastewater
Treatment Plant

The discharge of industrial waste to a municipality is governed by EPA
"Pretreatment Standards"(7), which require  that an industry remove any
waste pollutant which would not be removed by the municipality.  Since the
new Chesaning plant did not have design capacity for ammonia removal, the
high ammonia content of Peet Packing could be considered "incompatible" and
require removal to a level acceptable for direct discharge to the River
(Section 128.133).  Discharge to the Village therefore required an oxidation
ditch, one clarifier for solids retention, an aerobic sludge digester, a
control building, modification of the existing pumping station, and 823 m
(2,700 feet) of 20 cm (8 inch) force main.  The total estimated cost of the
Peet Packing system was $534,300, with a total annual cost of $140,000.
However, the Chesaning plant also required expansion to accommodate the
increased waste load.  The Village of Chesaning, at that time, had received
an EPA Step 3 grant for 75% of the project cost and had just taken construc-
tion bids for major treatment plant expansion which did not include capacity
for the Peet Packing Company.  The Village therefore would have had to
either abandon their grant and begin Step 1 and Step 2 planning anew or pay
for the additional expansion with 100% local financing.  It was therefore
decided it would be too costly in terms of rewriting the facilities plan,
redesigning the plant and implementing industrial cost recovery, to proceed
with joint treatment.

Alternative 6 - Additional Treatment with Seasonal Discharge

This system required an additional 4.6 hectares (11 acres) of aerobic ponds
plus an oxidation ditch, two clarifiers, an aerobic digester, chlorine con-
tact chamber, and a control building with chemical storage.  The total cost
of the system was $734,800, with a total annual cost of $139,400.

Alternative 7 - Land Disposal—Border Strip Irrigation

The border strip irrigation system required an additional 2.5 hectares (6
acres), 3.7 m (12 foot) deep storage pond for winter storage and 21 hectares
(50 acres) of irrigation cells plus an additional 61 m (200 ft.) border for
isolation.  The irrigation cells would receive 5 cm (2 inches) of wastewater
per week over 6 months of the year.  Each of 74 bermed cells, 15 x 183 m
(50 x 600 feet), would be flooded at 3.8 m3/min. (1,000 gpm) for approxi-
mately 30 minutes once a week.  Alfalfa hay would be grown on the land for
nutrient removal and crop recovery income.

The design basis for the land disposal system was:

                   Flow           760 m3/d (200,000 gpd)
                   BOD5            60 mg/1
                   S.S.            90 mg/1
                   NH3-N           50 mg/1
                   P               25 mg/1
                                     255

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 A series of monitoring wells were anticipated to ensure that  the  proposed
 application rates would not result in nitrate contamination of  the  ground
 water.

 An initial hydrogeological investigation of existing well  logs  in the  area
 indicated a site adjacent to the existing lagoons suitable for  such a
 system(8).  Initial cost estimates also showed the alternative  to be the
 most economical.   A site study was therefore initiated  which  showed a  clay
 layer 1.2-1.4 m (4-4.5 feet) below the surface with perched water at 0.9 m
 (3 feet) or less below the surface indicating poor drainage(9).   A  clay
 layer is advantageous  in a land disposal system as it protects  the  ground
 water below it from possible contamination; however, a  minimum  of 2.4-3 m
 (8-10 feet) is needed  above the clay to provide good drainage and bacterial
 reduction of the wastewater.  The proposed site was therefore unacceptable
 and the sand fill necessary to make the site acceptable made  the  cost
 totally prohibitive.   In addition, an alternate site within 3.2 km  (2  miles)
 of the aerobic lagoons was not apparent.
WASTEWATER TREATMENT  RECOMMENDED

The  initial indications  of  the  study were  that  land  application would be the
most advantageous  alternative.  After  further hydrogeological investigation
showed  the site  to be unacceptable, the  oxidation ditch alternative became
the  most  cost-effective  solution  for BOD,  S.S.,  and  ammonia reduction.

Following completion  of  the initial study,  the NPDES permit was modified in
part  in that  the ammonia removal  requirement was deleted.  The revised per-
mit  still required upgrading  of the existing lagoon  facilities to provide
80%  phosphorus removal and  disinfection.   Further removal of BOD5 and sus-
pended  solids was  also required.   Since  BOD and  S.S. discharge appeared to
reflect breakdowns of the blood evaporator and a raw waste "Hydrasieve" was
not  yet in use,  it was felt that  significant improvements in the BOD5 and
suspended solids levels  of  the  final effluent could be achieved by operation
of the  screen and  by  hauling  blood to  another suitable disposal facility
during  periods of  repair to the blood  evaporator.
Thus  the  proposed  system to meet  the July  1, 1977, effluent limitations was
phosphorus removal by chemical  addition  and clarification, and disinfection
by chlorine.  This system would treat  the  effluent from the existing aerobic
lagoons and discharge to the  River by  gravity.  A flow schematic is shown in
Figure  3.

The  system was to  consist of  a 9.2 m (30 foot) diameter clarifier with a
center  flocculation zone, a chlorine contact tank, a sludge storage tank,
chemical  storage and  feed equipment and a  control building.  The system was
to have capability for the  addition of either alum or ferric chloride in
conjunction with a polymer.

It was anticipated that  80  to 90% of the phosphorus could be removed along
with up to  60% of  the algae,  50% of the BOD5, and 50% of the suspended
solids.    Sludge storage would be provided and sludge would periodically (2-3
                                     256

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                                                                   DIVERSION
                                                                  STRUCTURE.
NJ
Ul
                      sues
                      PUKPPIT
TO TRUCK
FILL STATION
                      SLUDGE
                      DBA* OFF PIT
                                                                         EXISTING
                                                                         OUTFALL MANHOLE
                                                     EXISTING SEWER
                                                     FROM AEROBIC PONDS-N
                                                   -	^15:	/

                                            CHEMICAL FEED POINT
                                                            • n» . •rl-'X.     1     TO RIVERA
                                                                                                              CHLORINE DIOXIDE
                                                                                                              FEED POINT
QiLDBINf
CONTACT
TANK
                                                                                        FLUME


                                                                                        0  VALVES
                                                                                             SLUCE GATES
                                                                                             STOP PLATES
                                                -TO ANAEROBIC LAGOON
                                     Figure  3.   Process  flow schematic for phosphorus  removal
                                                   and disinfection.

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 times a week)  be removed by tanker truck and spread on farmland.   The  esti-
 mated cost of  the facility was $226,000, with an annual cost,  including
 amortization,  of $55,000.
 PROCESS  DESIGN

 Phosphorus  Removal

 Phosphorus  removal  from wastewater by  chemical  addition and clarification
 has  become  common at municipal wastewater  plants  throughout Michigan and
 other  Great Lakes States.   Phosphorus  removal following lagoon treatment,
 however,  has not  been  practiced  extensively  as  it has not yet been required
 of small municipalities with  lagoons.  However, pilot studies for the City
 of Ludington,  Michigan, demonstrated that  similar design bases can be used
 for  lagoon  removals as for  secondary biological treatment (10) .

 The  precipitation reaction  of phosphorus with any metal ion is similar to
 that of  aluminum  ion which  can be expressed  as  follows :

                         A13+ +  P043~ - - A1P04 |
which gives a mole ratio of A1:P of 1:1 or a weight ratio of 0.87:1.  How-
ever, the reaction and physical settling is dependent on interf erring
reactions, coagulation requirements, pH, and temperature, which necessitate
chemical addition in excess of the 1:1 mole ratio of A1:P for efficient
removal.  The results of published studies of phosphorus removal with alum
indicates that  80% phosphorus removal typically requires a mole ratio of
between 1.5 and 2. 3(11) (12) (13) (14) (15) (16) .

The chemicals used in phosphorus removal usually provide ions of aluminum or
iron, or calcium.  Aluminum ion is usually supplied by aluminum sulfate
(alum), Al2 (504)3' 14H20,  or by sodium aluminate, Na2Al204 or NaAK^.  Iron
is usually supplied by ferric chloride, FeCl3» or ferrous sulfate, FeS04 or
ferric sulfate, Fe2(S04)3.  Calcium ion is usually supplied by lime, CaOH2
or CaO.  Waste alum sludge from water treatment plants and waste pickle
liquor from steel production have also been used for considerable cost
reduction.  Alum was chosen to be used at Peet Packing because of its
availability and because it is somewhat less corrosive than ferric chloride.

Polymer addition can enhance coagulation of the phosphorus precipitate and
thus increase removal efficiency.  Optimum dosages appear to vary greatly
with the type of polymer used and wastewater characteristics, dosages
between 0.2 and 1.0 mg/1 are common.   A flocculation system will also
enhance the coagulation of the phosphorus precipitate with velocity gradi-
ents of 50 sec.~l typical.

The settling equipment for phosphorus removal at Peet Packing includes a
9.2m (30 foot) diameter clarifier with a 3 m (10 foot) side water depth, a
2.6m  (9  foot) center flocculation well with a variable speed mechanical
                                     258

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turbine type flocculator, sludge collector and surface skimmer arms, scum
box, weirs and baffles.  A control building houses a 18.9 m3 (5,000 gal.)
chemical  (alum) storage tank, a .49 m3/d (130 gpd) diaphragm type chemical
feed pump, a .57 m   (150 gal.) polymer storage tank with wetting funnel, a
mixer, and a .17 m3/d  (45 gpd) diaphragm type polymer feed pump.  A non-
potable water pump recycles clarified effluent for dilution water for both
the alum  and the polymer.

A telescoping valve  allows withdrawal of clarifier sludge to a thickening
tank from which a second telescoping valve can be used to decant the super-
nate back to the clarifier.  Thickened sludge can then be transferred to a
submersible pump sump  from which it can be recycled back to the clarifier,
pumped to a truck fill station, or pumped back to the anaerobic lagoon.
Additional related equipment provided includes a 10 cm (3 inch) flume for
flow measurement and recording, and a flow proportional composite sampler.

The typical dosage requirements for 80% phosphorus removal were estimated
assuming  a 1.7 mole ratio of A1:P, a 20 mg/1 influent phosphorus concentra-
tion, and a flow of  756 m3/d (200,000 gpd) as follows:

     756  m3   1.000 kg   20 kg P   27 kg Al   , ,   ,
     	-	 x 	T—°- x  , ~i°— x  „., °—— x 1. 7 mole ratio x
       day       mj       10° kg    31 kg P

     594  kg Alum        m3	   .4 m3 _ 16.8 liters
                 x
     or
      54 kg Al     611.3 kg Alum    day        hr.

        200,000 gal.   8.34 Ibs.   20 Ibs. P   27 Ibs. Al
——a	 x	 x  ir.f.  . — x 01  • 	— x 1.7  mole ratio  x
 day         gal.        10°  Ibs.    31  Ibs.  P
     594 Ibs. Alum   gal, of Alum  _ 106 gal, of Alum
      54 Ibs. Al   X 5.1 Ibs. Alum ~        day

Based on an estimated cost of $0.21 per gallon, the expected cost of alum
will be $22.60 per day or $8,250 per year.

Disinfection

Disinfection with chlorine is utilized throughout the country; however,
recent awareness of potential formation of harmful chlorine compounds and
residual toxicity in the stream, combined with the high ammonia levels of
the Peet Packing effluent, led to the investigation of alternate methods of
disinfection.

Chlorine dioxide was chosen because it does not combine with ammonia to pro-
duce chloramines, it is a stronger oxidant than chlorine(17), and it has
the potential for disinfection at smaller dosages than chlorine solution.
When chlorine is added to a wastewater, it rapidly combines with ammonia to
form monochloramines, dichloramines and trichloramines, all of which are
termed combined chlorine residuals.  The monochloramines and dichloramines
have reduced disinfecting power and are extremely slow reacting(18), and it
may take up to two hours contact time to be useful as a disinfectant(19).
                                     259

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 "Free chlorine" is a term used for hypochlorous  acid (HOC1) which  is  a
 stronger,  much faster acting disinfectant.   Some estimates indicate dis-
 infection  capability of monochloramine is approximately one-one hundredth
 that  of free chlorine(19) .   In order to obtain a "free chlorine residual"
 in wastewater containing ammonia,  enough chlorine must be added to result  in
 "breakpoint chlorination" which requires a minimum of 10 mg/1  of chlorine
 for every  1 mg/1 of ammonia (19) (20) .   In drinking water treatment, "break-
 point"  chlorination is  a common practice to ensure complete disinfection.
 In wastewater disinfection,  it usually is not  necessary to "breakpoint"
 chlorinate to achieve the disinfection levels  required (based  on fecal
 coliform);  however, since chlorine dioxide  is  a  disinfection agent equiva-
 lent  to "free chlorine", it  has the  potential  for achieving the required
 disinfection levels at  a much smaller dosage.

 The generation of chlorine  dioxide requires the  mixing of a chlorine  solu-
 tion  and sodium chlorite  (NaC102).   The reaction is  as follows:

                      2  NaC102 + Cl2 — - 2 C102  +  2 NaCl

 In  theory  therefore,  1.00 kg of chlorine dioxide requires 1.34 kg  of  pure
 sodium  chlorite and 0.5 kg of chlorine (19) .  Since sodium chlorite is
 typically manufactured  80% pure, 1.68 kg of sodium chlorite is  required and
 an  overdose  of  chlorine is used to ensure a complete  reaction,  therefore a
 1:1 ratio by weight of  chlorine to sodium chlorite is  recommended (19 ).  The
 procedure is  to pump  a  sodium chlorite solution  with  a metering  pump  through
 a glass clyinder filled with porcelain rings;  the cylinder is  also fed
 chlorine solution from  a standard  chlorinator.   When  the proper  amount of
 chlorine is  added to  the sodium chlorite solution,  the mixture  turns
 greenish yellow providing visual indication of the formation of  chlorine
 dioxide.  Sodium chlorite is  shipped  dry and should be mixed with water to
 a convenient strength daily.

 The typical  chlorine dioxide  dosage requirements  for  the Peet Packing
 Company were estimated  assuming 2 mg/1 chlorine  dioxide would provide a
sufficient fecal  coliform kill.  With  a flow of  760 m3/d (200,000 gpd) , the
estimated feed rates can be  calculated  as follows:

     760 m3   1,000 kg x 2 kg C102 = 1.5 kg  C102
       day       m-3       10° kg         day

     1.5 kg C102    1.68 kg NaC102 required  = 2.5 kg NaCIO?
         day     X         kg C109                 day

                   .            .,2.5 kg Cl?
     for a 1:1 ratio also provide - -r3 - ^


        inn nnn   j   8.34 Ibs .   2 Ibs . C102   3.3 IbS. C102
     or 200,000 gpd x -    - x  1Q6 lbs>   - -   -
     3.3 Ibs.  CIO?   1.68 Ibs. NaCIO? required = 5.5 Ibs. NaCIO?
          day      X        Ibs. C102                  day
                                    260

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     and for a 1:1 ratio also provide —^	2.
                              v         day

Based on an estimated cost of sodium chlorite and chlorine of $0.80 and
$0.20 per pound, respectively, the expected cost of year-round disinfection
would be $5.50 per day or $2,020 per year.

It is difficult to estimate the required dosage of straight chlorine to
achieve disinfection at the Peet Packing Company; however, an estimated
usage of 20 to 30 mg/1 is not unreasonable considering the 50-60 mg/1 of
ammonia present in the effluent.  The estimated chlorine usage at 20 to
30 mg/1 would be 15-23 kg/day (33-50 Ibs./day) and the expected cost of
year-round disinfection would be $6.60 to $10.00 per day or $2,400 to $3,650
per year.

The actual cost savings for the use of chlorine dioxide on a high ammonia
waste will only be shown through operational experience; however, the
potential is significant and the additional capital cost to provide the
capability to generate chlorine dioxide in addition to normal chlorination
equipment is modest.  At Peet Packing the additional diaphragm metering
pump, 105 gallon tank, tank stand, solution diffuser,-generator (glass
cylinder), back pressure valve, pressure relief valve and anti-siphoning
valve had a total cost of $2,300.

Additional related equipment includes a PVC chlorine dioxide (or chlorine)
diffuser located in a flow channel prior to the flow measurement flume and
following clarification, and two concrete contact chambers 3 m long x 1.2 m
wide x 2.4 m deep (10 ft. long x 4 ft. wide x 8 ft. deep) each, of which
will provide 35 minutes contact time at a flow of 760 m^  (200,000 gpd).
Redwood planks are used for baffling to provide an over and under flow
pattern and to avoid short circuiting.

It should be noted that dry sodium chlorite requires special handling in
that it is flammable when it is in contact with organic material such as
gloves, sawdust, brooms, etc., and can ignite with heat or friction(19).
No danger is involved in handling the material if care is exercised and
precautions are followed, such as large amounts of flushing water should be
used to wash down any spills.  Sodium chlorite once mixed with water pre-
sents no further hazard.

It should also be noted that test samples tested once a month over a 2 year
period indicate that the fecal coliform counts of the aerobic lagoon efflu-
ent remain below the 400/100 ml discharge requirement much of the year, and
usually only go above that level when the aerobic ponds are frozen over.
This indication also needs to be verified, however, as during warmer months
algae interference with the membrane filter test used has been noted and may
be creating erroneous results.
                                    261

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 CONSTRUCTION  SUMMARY

 The  construction  of the wastewater  treatment facility was advertised for
 competitive bids  in two steps.  Since  the clarifier equipment, including
 weirs  and baffles, required  the longest delivery time, bids for this equip-
 ment were solicited prior to completion of plans and specifications for the
 remaining portions of the facility.  Proposals were received from three
 manufacturers in  January, 1977, and the equipment was awarded to the lowest
 bidder. Following completion of plans  and specifications, an "invitation
 for bids" was advertised.  Included in the contract documents was an assign-
 ment of the previously accepted clarifier equipment to the contractor's bid,
 this made the equipment supplier responsible to the contractor.  The Peet
 Packing Company chose to do  all of  the electrical and instrumentation work
 with plant personnel.  Construction bids were received in March, 1977, and
 the contract was  awarded to  the lowest bidder at $193,000.  Construction
 began  on May 1, 1977, and was substantially complete by October 31, 1977.
INITIAL OPERATING EXPERIENCE

Difficulty in getting the facility fully operational has been experienced
due to hard winter weather; however, alum and polymer have been fed for
phosphorus removal for the majority of the period between November, 1977,
and the time of this writing, March, 1978.  A limited amount of data has
been analyzed during this period using "Standard Methods"(21).  It appears,
however, that 80% phosphorus removal can be achieved using the original
estimated alum dosage of 1.7:1 mole ratio of A1:P.  This dosage is equiva-
lent to a 1.5:1 weight ratio of A1:P, or 25 liters alum per kg incoming
phosphorus (3 gal. alum/lb. incoming P) assuming an alum solution of 1,332
kg/m3 (11.1 Ibs./gal.) A12(804)3-1^20 with 60 kg/m3 (0.5 Ib./gal.) Al.
The alum/phosphorus sludge characteristics observed have been very encour-
aging thus far, as the sludge both settles and thickens well.  No disinfec-
tion data has yet been attained.
CONCLUSIONS

1.  An evaluation of the disinfection of a lagoon effluent with high ammonia
    concentrations indicates that the use of chlorine dioxide is not only
    more environmentally sound but potentially less costly than disinfection
    with chlorine.

2.  Phosphorus removal from lagoon effluent can be reliably achieved with
    chemical addition and clarification.  Chemical requirements are similar
    to those experienced at secondary municipal treatment plants, and
    sludge characteristics appear to be excellent.

3.  An evaluation of alternatives for ammonia removal indicated that land
    application utilizing border strip irrigation was more economical than
    mechanical treatment if an appropriate site can be found.  Of a number
    of mechanical treatment alternatives evaluated, an oxidation ditch
    system appeared to be the most economical.


                                     262

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                                REFERENCES
 1.  Spicer Engineering Company, "Report on Waste Treatment for Peet Packing
     Company, Chesaning, Michigan", January (1966).

 2.  Dart, M. C., "Treatment of Waste Water from the Meat Industry", Pro-
     cess Biochemistry, June (1974).

 3.  Witherow, "Waste Treatment for the Small Packer", The National Pro-
     visioner, Vol. 169, No. 13, p. 8-14, September 30 (1973).

 4.  Witherow, "Waste Treatment Evaluation", The National Provisioner,  Vol.
     169, No. 14, p. 15-23, October 6 (1973).

 5.  E.P.A., "Meat Products Point Source Category Effluent Guidelines and
     Standards", Federal Register, Vol. 39, No. 41,  p. 7894-7908,  February
     28 (1974).

 6.  E.P.A., "Nitrification and Denitrification Facilities", Technology
     Transfer Seminar Publication (1973).

 7.  E.P.A., "Pretreatment Standards", Federal Register, Vol. 38,  No. 215,
     p. 30982-30984, November 8 (1973).

 8.  Hilty, Robert D., "Hydrogeological Investigation Phase I,  Peet Packing
     Company", Keck Consulting Services, Inc., September 11 (1975).

 9.  Hilty, Robert D., "Hydrogeological Investigation Phase II, Peet Packing
     Company", Keck Consulting Services, Inc., October (1975).

10.  Williams, T. C. , and Malhotra, S. K., "Phosphorus Removal  for Aerated
     Lagoon Effluent", J. Water Pollution Control Federation, Vol. 46,  No.
     12, December (1974).

11.  E.P.A., "Process Design Manual for Phosphorus Removal", Technology
     Transfer (1971).

12.  Long, D. A., Nesbitt, J. B., and Kountz, R. R., "Soluble Phosphate
     Removal in the Activated Sludge Process—A Two-Year Plant  Scale Study",
     Presented at the 26th Annual Purdue Industrial Waste Conference, Purdue
     University, Lafayette, IN, May (1971).

13.  Hais, A. B., Stamberg, J.  B., and Bishop, D. F., "Alum Addition to
     Activated Sludge with Tertiary Solids Removal", AICHE Symposium Series,
     Vol.  68, p. 35 (1972).

14.  Directo, L. S., Miele, R.  P., and Masse, A. N., "Phosphate Removal by
     Mineral Addition to Secondary and Tertiary Treatment Systems", Pro-
     ceeding of the 27th Industrial Waste Conference, p. 369, May 2, 3, and
     4 (1972).
                                     263

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15.  Zenz, D. R., and Pivnicka, J. R., "Effective Phosphorus Removal by the
     Addition of Alum to the Activated Sludge Process", Proceedings of the
     24th Industrial Waste Conference, p. 273-301 (1969).

16.  Baillod, C. R., Cressey, G. M., and Beaupre1, R. T., "Influence of
     Phosphorus Removal on Solids Budget", J. Water Pollution Control
     Federation, Vol. 49, p. 131-145 (1977).

17.  Weber, Walter J., "Physicochemical Processes for Water Quality Con-
     trol", Wiley-Interscience, New York (1972).

18.  Metcalf & Eddy, Inc., "Wastewater Engineering", McGraw-Hill Book
     Company, New York (1972).

19.  White, G. C., "Handbook of Chlorination", Van Nostrand Reinhold Co.,
     New York (1972).

20.  Sawyer, C.  N., and McCarty, P. L., "Chemistry for Sanitary Engineers",
     McGraw-Hill Book Company, New York (1967).

21.  APHA, AWWA, and WPCF, "Standard Methods for the Examination of Water
     and Wastewater", 13th Edition (1971).
                                     264

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              PHYSIOCHEMICAL TREATMENT OF RENDERING WASTEWATER
                           BY ELECTROCOAGULATION

                                    by

                  Ernest R. Ramirez* and Odgen A. Clemens*
ABSTRACT

A large rendering plant processes between 500 and 700 tons of material per
day.  It handles feathers, fats, various forms of meat, etc. in a Carver-
Greenfield rendering operation.  This unit produces approximately 1000 M^
per day of wastewater, while the air scrubber discharge, feather cooling
water discharge, and cooling tower overflow account for 871 M^/day, 757
M^/day and 246 M3/day, respectively.  The 1000 M3/day from the rendering
operations is processed through a two-step electrocoagulation system before
it is discharged to the city.

The wastewater treatment operation uses both sulfuric acid additions as well
as alum for coagulation.  The process is operated close to the zero zeta
potential (zero surface charge) of the pollutant particulates.  Extremely
high reductions in suspended solids (97%) and fats and oils (98%) are
achieved with the two-step electrocoagulation technology.

Skimmings are dewatered in the same basin in which they are formed by using
dissolved air dewatering.  Their solid content lie between 13.7 weight per-
cent and 17.5 weight percent.

INTRODUCTION

A large rendering plant in North America processes approximately 600 tons
of renderable material per day.  The plant has only one objective; that
involves rendering.  Wastewaters from the plant are discharged to the
municipality and subsequently to a river.  The municipality has established
guidelines for receiving plant discharge and has set the following figures
as acceptable for effluent from a wastewater treatment system:

      A.  Suspended Solids - not to exceed 200 mg/1.

      B.  Hexane Extractables - not to exceed 100 mg/1.

      C.  BOD was not included in the restriction list.

The guidelines also specify that the limits established are for water leav-
ing the pretreatment system.  Dilution with other waters, such as cooling
waters, etc., would not be considered as a measure of reducing pollutants
in the water.
* Swift Environmental Systems Company, Oak Brook, Illinois

                                      265

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 The local environmental agency also specified that spills and other mishaps
 in the plant will not be permitted to influence the restrictions estab-
 lished.  In this regard it became mandatory to include a recycle system in
 the pretreatment unit should these mishaps occur.   This safeguard is carried
 out by turbidimetric control.

 Material rendered at the plant includes carcasses, bone fragments,  hair,
 feathers, etc.   Discharge waters leaving the plant must fall  within the pH
 range of 5.5 to 9.5 units.

 Odor problems encountered at the plant included that of ammonia  mercaptans
 and hydrogen sulfide.   Ultimately it was understood that these odors would,
 in due time,  also be eliminated by proper treatment procedures.   Management
 decided that it would be more  intelligent to handle the problems piecemeal
 and start by first treating the wastewater to meet discharge  permit guide-
 lines.   (This decision was,  indeed,  unfortunate.)

 Plant Equipment and Wastewater Sources

 The heart of  the rendering  plant consists of a Carver-Greenfield rendering
 unit.   Wastewaters leaving  the Carver-Greenfield overall operation  pass
 through a natural flotation-sedimentation basin having dimensions of 9  feet
 wide  by 40 feet long by 5 feet deep.   This basin has both a top  skimmer
 device  as well  as a bottom  drag.   Waters  entering  this sedimentation-
 flotation basin emanate from:   (a)  feather condensates,  (b) feather pit,
 (c)  truck wash,  (d)  Carver-Greenfield  condensates,  (e)  raw material pit,
 (f)  blood system,  (g)  Carver-Greenfield  ejector condensates,  and (h)  miscel-
 laneous  floor washings,  etc.   A breakdown of  the water volumes and  their
 pollutant  loading is given  in  Table  1.

 TABLE 1.   WASTEWATER SOURCES ENTERING  NATURAL FLOTATION-SEDIMENTATION BASIN



Feather Condensates
Feather Pit
Truck Wash
Carter-Greenfield (C.G.) Condensates
Raw Material Pit
Blood System
C.G. Ejector Condensates
Miscellaneous, Floor Wash, Etc.

GPD
approxi.
10,000
21,000
16,000
70,000
21,000
30,000
100,000
20,000
BOD5
Total
mg/lt
6,540
4,430
2,270
4,210
10,200
57,000
700
2,500 '

SS
mg/lt
2250
5320
527
1510
4100
910
-
4100

FOG*
mg/lt
20
-
126
800
2100
60
-
2210
          Total
* Fats, oils and grease.
288,000
                                     266

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Another three sources of wastewater present at the plant are given in Table
2.  These wastewaters do not pass through the natural flotation-sedimenta-
tion basin and will be discharged directly to the city.

                 TABLE 2.  OTHER DISCHRAGE SOURCES IN PLANT



Air Scrubber
Feather Cooling Water
Cooling Tower Overflow

M3/Day
Volume
871
757
246

GPD
Volume
230,000
200,000
65,000
BOD5
Total
mg/lt
-
-
~

SS
mg/lt
270
-
300

FOG
mg/lt
15
-
~
In summary, four principal wastewater sources emerge from the plant.  These
are:  flotation-sedimentation basin, air scrubber discharge, feather cooling
water discharge, and cooling tower overflow.  Total water discharge from the
plant is in the range of 2974 M^/day (780,000 GPD).  The rendering plant is
primarily concerned with the wastewater in the natural flotation-sedimenta-
tion basin which represents approximately 1000 M^/day.  The analyses of
these wastewaters are given in Table 1.

Optimum Treatment Determination of Rendering Wastewater

Wastewaters from the air scrubber discharge, feather cooling water dis-
charge, and cooling tower overflow will not be treated by the LectroClear
installation.  These waters will simply be added to the discharge from the
LectroClear operation.

In evaluating the wastewater, the following three steps were carried out
using a batch-type two-step portable LectroClear unit together with a
streaming current detector.

      A.  Determination of the pH of zero streaming potential (also zero
          zeta potential).

      B.  Determine the minimal treatment of alum or ferric sulfate to meet
          goals (one liter samples).

      C.  Determine the optimum cost effective dosage for treating the
          wastewater to comply with the established discharge guidelines of
          less than 200 mg/1 of suspended solids and less than 100 mg/1 of
          hexane extractables (one liter samples).

A series of analyses were carried out on the wastewater from the natural
flotation-sedimentation basin on different dates.  In each case a composite
sample was taken.   The results of these analyses are shown in Table 3.
                                     267

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                  TABLE  3.   ANALYSES  OF WASTEWATER  LEAVING
                    NATURAL FLOTATION-SEDIMENTATION BASIN
                             BOD5


Sample 1
Sample 2
Sample 3
Total
mg/lt
7480
7800
4800
Soluble
mg/lt
3400
3500
1470
SS
mg/lt
4475
2720
3280
FOG
mg/lt
880
740
820
Determining pH  for  Zero  Zeta  Potential

A  streaming current detector  (manufactured by Waters Associates,  Inc.*) was
used  to  determine the  surface charge  on  the pollutant particulates.  This
was done by taking  small  50 cc aliquot samples and determining  the stream-
ing current value at various  pH values.   Sulfuric acid was used for pH
adjustment.  Results of  this  study are shown in Figure 1.  These  results
clearly  show that the  surface charge  on  the pollutant particulates average
approximately zero  at  a pH of 4.2.  Also shown is that, as the  pH is reduced
and as it approaches 4.2, the charges on the pollutant particulates become
less  and less.  The reduction in surface charge (negative) encourages the
particulates to agglomerate and aggregate.  On letting this wastewater
stand (at pH 4.2) for  1/2 hour, it was found that most of the pollutants
agglomerated and either floated or sank.  The supernatant liquid  had a
Jackson  Turbidity Value of 500 units.  This fact confirms that  at a zero
streaming potential the tendencies for pollutants to agglomerate  are indeed
appreciable.  The relationship between the amount of acid needed  to adjust
pH as a  function of  pH is shown in Figure 2.

Power requirements  needed to  satisfactorily treat the wastewater  at a zero
zeta potential when  only sulfuric acid is used as the coagulant (and 6 ppm
anionic  polymer) are shown in Figure  3.   The results of Figure  3  show that
the wastewater can  be  reduced  to a turbidity of 300 Jackson Turbidity Units
by the application  of  5 ampere  minutes (at 12 volts) per liter  of wastewater
processed.  A detailed analyses of the treated wastewater at 5  ampere
minutes  per liter are  shown in  Table 4.   Because this operation is carried
out at a zeta potential approximately equal to zero, it is being  referred
to as LectroClear-Z.
* 16 Fountain Street, Farmingham, Mass.
                                     268

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                    LECTRO-CLEAR  Z  TREATMENT

      STREAMING  POTENTIAL  VS.  pH  OF  RENDERING  WASTEWATER
ho
a\
vo
                             FIG.
PI-II. ELECTRODES

RUN AT 87 *F

NO USE OF METAL COAGULANT

(PH ADJUSTMENT ONLY H?S 04)

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            RENDERING WASTEWATER (7-5-77)
 pH
to
^J
o
    4.5 -
     4.0 -
                        FIG.  2
              40O
800     1200

 H2S04(ppm)
1600
2000

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   Electrolytic Power Input As A Function Of Turbidity
        At pH Of Zero Surface Charge (Acid)
   10,000
JTU
   5,000 H
     500-
                    FIG.  3
            I. ph«4.2
           2.HeS04 Adj. Only (1500 mg/lt)
           3. No Metal Coagulant
                                              300JTU
1.0    2.0    3.0    4.0
  Ampere Minutes/It
                                          5.0

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                TABLE 4.   TREATING RENDERING WASTEWATER WITH
                  ELECTROCOAGULATION AT ZERO ZETA POTENTIAL
    Sample
 Description
 Rendering
 Wastewater
Treatment
(a) H2S04 to
    pH 4.2
(b) 6 mg/lt of
    anionic polymer
(c) 5 ampere min/1
     SS (mg/lt)
Influent   Effluent
            FOG (mg/lt)
        Influent   Effluent
  3680
310
750
80
 Treating Rendering Wastewater with Trivalent  Metal  Coagulants  Only

 It  was  found  that  the  rendering wastewater  could  be satisfactorily  treated
 to  a  zero surface  charge when 500  ppm of ferric sulfate  or  500 ppm  of  alum
 were  used in  the treatment.   Under these conditions,  the pH of the  waste-
 water was reduced  from its  original value of  7.4  to a value of 6.2.  With
 this  treatment  the wastewater could be satisfactorily treated  with  a power
 input of 2 ampere  minutes (at 12 volts)  per liter.   Analysis of the waste-
 water so treated is given in  Table 5.   The  turbidity of  this wastewater was
 found to be 50  Jackson turbidity units.   Since this process uses only  a
 metal coagulant (and an anionic polymer  of  6  mg/lt),  it  is  referred to as
 LectroClear-M.   (Figure 4).

                TABLE 5.   TREATING  RENDERING WASTEWATER WITH
                    ELECTROCOAGULATION  AND FERRIC  SULFATE
   Sample
Description
Rendering
Wastewater
Treatment
     SS (mg/lt)
Influent   Effluent
            FOG (mg/lt
        Influent   Effluent
(a) 500 mg/lt
    Ferri Floe
(b) 6 mg/lt
    anionic polymer
(c) 2.0 ampere min/lt
  3680
32
750
15
It will be noted that in this particular wastewater  the LectroClear-Z
process has higher chemicals costs  than does  the LectroClear-M operation
(see Figure 5).  Power input to obtain satisfactory  results are also con-
siderably higher in the case of the LectroClear-Z method.  The most cost
effective chemical treatment, however, is achieved by combining the use of
sulfuric acid in addition to a trivalent metal coagulant.  Consequently,
the most cost effective operation taking into account chemicals is deter-
mined by using equation 1 for a series of satisfactory treatments.
                                     272

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  Electrolytic Power Input Vs Turbidity
  At Zero Surfoce Charge (Trivalent
  Metal Coagulant)
              FI6.  4
1,000-
 500-
                  . pH»6.2
                 2.6ppm anionic polymer
                 3. Ferric sulfate 500mg/lt
         0.5      1.5   2.0
         Ampere Minutes/It
                  273

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    |/3.7»8
  GRAPHICAL  DETERMINATION OF MINIMUM
  COSTS FOR  LECTRO  CLEAR-Z-M
          (EQUATION I)
NO
                                    POLYMER
0   250   500
500 400   300
,
6.1
     5.8   5.4
                            750  1000  1250  1500   H2S04 mg/lt 66* Be
                            250   170   100   25   ALUM  mg/lt USED
                              CHEMICALS USED
                            5.0    4.6   4.5   4.2   PH

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Equation  1  -  Chemical  Costs

$/1000 gal  =  $/3.788M3 =  .00834  [AxB+CxD+ExF]
     where:
               A = mg/lt  trivalent coagulant used
               B = $/lb trivalent metal coagulant
               C = mg/lt  sulfuric acid used
               D = $/lb delivered H2S04
               E = mg/lt  polymer used
               F = $/lb polymer used

     for  plant in question:
               B = $.09/lb
               D = $.03/lb
               F = $2.50/lb
               E = constant 6 mg/lt

Most Cost Effective Treatment

By using  equation 1 in conjunction with laboratory data, one arrives at the
results given in Figure 5.  In essence, all treatments given in the abscissa
of Figure 5 treat the wastewater satisfactorily.  The results show that the
most cost effective treatment is 500 mg/lt H2S04  (66° Be), 300 mg/lt alum
and 6 mg/lt of anionic polymer.  Chemical cost of this treatment for the
plant in  question is $.476 per 3.788 M3 (1000 gallons).

The most  cost effective treatment in plant A may not necessarily be so at
plant B.  Different cost  of chemicals at different plants will necessarily
lead to different cost effective treatments.  It is, therefore, necessary
that each plant determine its cost effective treatment based on chemical
costs in existence at that plant.  Hardness of the wastewater has an over-
whelming effect on the most cost effective treatment.  The wastewater at
this plant was highly buffered with organic salts.  This accounts for the
exceptionally large amounts of acid needed.  (See Figure 3.)

BASIC PRINCIPLE OF ELECTROCOAGULATION

The theory and principle  of operation of the two-step electrocoagulation
technology has been adequately described in prior literature (1, 2, 3, 4,
5, 6).  A summary of the  process, however, is given below.  The technology
involves  two  steps, the first having a duration of approximately 2 minutes.
This step is  called coagulation and the container in which it takes place
is referred to as the coagulation cell or contact cell.  A cardinal point
of this first-step operation is that coagulants are added to the wastewater
prior to the  entrance into the coagulation cell.  Likewise, pH adjustments
are also made prior to the coagulation cell.  Microbubbles in the diameter
range of 50 to 100 microns are introduced into the coagulation cell at a
concentration of 1 million to 100 million microbubbles per liter of waste-
water.  The 2-minute dwell time in the coagulation cell allows for intimate
collisions between the pollutant particulates and the microbbubles.  These
                                     275

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 collisions result in a pairing off of particulates with microbubbles.  Upon
 leaving the coagulation cell, a polyelectrolyte is added and, at that
 point, a gross floe is formed in the flotation basin.  This gross floe has
 entrapped in it better than 80% of the microbubbles generated in the coagu-
 lation cell.  It is these microbubbles which provide buoyancy to the floe.

 The flotation basin is the second step of the electrocoagulation technology.
 It involves a dwell time of approximately 25 minutes and electrolytic micro-
 bubbles are again used to float particulates to the surface of the water
 where they are subsequently skimmed off by a mechanical skimmer.  A schema-
 tic of this two-step operation using electrolytic power is shown in Figure
 6.  While this paper deals with electrolytic power, both dispersed air and
 dissolved air microbubbles can also be effectively used in both the coagula-
 tion cell and the flotation basin.  When electrolytic power is used, cur-
 rents in the range of 1.3 ampere minutes/It (5 ampere minutes per gallon)
 are used in the coagulation cell and approximately 1 ampere minute/It (4
 ampere minutes per gallon) in the flotation basin.  Voltages employed are DC
 and in the range of 10 to 15 volts.  The fact that the process actually
 treats the wastewater twice (once in each of the two steps) accounts for
 the improved treatment results over and above that attained in a dissolved
 air or electroflotation basin alone.

 DESIGN CRITERIA AND CONSTRAINTS

 The plant management has established  that it would be important to have the
 skimmings with a minimum of water.   The reason for this requirement is the
 plant has plans to render the skimmings for their protein and fat values.
 High water content would require higher rendering energy inputs and require
 a  more costly operation.   In view of  this requirement, it was decided to
 dewater  the  skimmings in the basin itself.   This is carried out with the
 use of dissolved air.   The operation  takes  place in the electroflotation
 basin itself and is restricted to the first quartile of the basin,  namely
 just  as  the  skimmings are about to leave the basin.

 For dewatering to  be effective there  must be a skimmings blanket height of
 no  less  than 3 inches;  a  skimmings  height of 4 inches or more is preferred.
 Under these  conditions  it  would require that the skimmer arms be placed on
 a  timer  system whereby  they would move  2 minutes out of every 4 minutes.
 (This ratio  is  not  fixed  but  is a variable  depending on the plant in ques-
 tion. )

 The use  of large amounts  of metal coagulant (500 ppm)  generally produces
 skimmings  of  higher  water  content and overall  greater volume.   Because of
 the constraints  placed  by  the  rendering operation,  it  was decided to use a
 LectroClear-Z-M operation  where only  a  small amount  of trivalent metal
 coagulant was  added  (less  than 100  ppm).

 Since management has  decided  that the skimmings  would  be rendered,  it  was
 decided  to use  the LectroClear-Z-M  process  where only  a small amount of
metal coagulant  is added.
                                     276

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                 FIG. 6


           SCHEMATIC-RENDERING
     .(EMBRYO FLOC)

CONTACT) &Ji
 CELL /i REV. /
       ISO' 1
      ism*.!
                                   LECTRO-CLEAR
                                       TANK

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The plant management also felt that the use of the natural flotation-sedi-
mentation basin will not be changed because substantial amounts of readily
renderable fat were obtained from this operation.  In this regard, the
unit pays for its keep and, therefore, will not be altered.

In summary, it was decided that the final wastewater treatment design would
consist of a LectroClear-Z-M unit which would incorporate a dewatering unit
in the first quartile of the flotation basin.  Both an electrocoagulation
cell and an electroflotation basin would be used in the operation.  Manage-
ment further expressed the desire to obtain a stand-by dispersed air device
as a source for microbubbles in the coagulation cell.  This means that the
electrocoagulation unit could be run either with electrolytic energy or
mechanical energy (dispersed air).  A failure in the rectifier would cer-
tainly make this decision worthwhile.

FINAL DESIGN

The final design for the LectroClear unit installed in this plant has a
capacity of 1.14 M^ (300 gallons) per minute.  It consisted of the follow-
ing:

      A.   One coagulation cell with a 2-minute retention time having an open
          top vortex chamber.   The cell housed 90 Duriron TA-2 electrodes
          each 7 feet long.   Surface-to-surface vertical spacing between
          electrode pairs is 3/8 inch.  Horizontal spacing (surface to
          surface) between a set of electrode pairs is 2.5 inches.  Recti-
          fier for the electrocoagulation cell is 2000 amps with a maximum
          voltage setting of 20 volts.  (See Figure 7.)

      B.   A dispersed air device precedes the coagulation cell and will be
          used on a stand-by basis.   Motor used for the dispersed air
          device is 2 horsepower.   (See Figure 8.)

      C.   The electroflotation basin is 8 feet wide,  38 feet long and 5
          feet deep with 47  electrode  pairs.  (See Figure 9.)

      D.   The skimmer device will not  be perfectly level but will have an
          upward tilt of 6 inches per  100 lineal feet.  This tilt will per-
          mit the basin to operate with a skimmings blanket of at least 3
          inches on the influent side.  (See Figure 11.)

      E.   The first quartile of the  basin will use 30% recycled dissolved
          air for dewatering the skimmings.   The dissolved air is introduced
          perpendicular to the wastewater flow with six 1-inch tubes, three
          on  each side  of the  basin.   The level at which the dissolved air
          is  introduced is exactly at  the mid-section of the basin.   (See
          schematic 11.)

      F.   Four  baffles  with  50 percent free  passage and with 2-1/2 inch
          circular holes  was used.   This condition minimized channeling in
          the electroflotation basin.   A holding tank of approximately
          100,000 gallons was  used to  equalize the flow.  (See Figure 10.)

                                    278

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        SCHEMATIC-ELECTROCOAGULATION CELL
                 FIG. T
to
•vj
VO

-------
                   Figure 8.  Dispersed air device.

Note the dispersed air device is placed just before the coagulation cell
(to the right).

-------
t-J
00
H
                                    Figure 9.  Electrode  arrangement  in basin.


                                Wiring is passed  through  a rubber  pressure device.

-------
ho
                                Figure 10.   View of electroflotation basin and baffels,

-------
                                          MODIFIED LECTRO-THIC  UNIT
Ni
00
                                              SKIMMER ARM TRAJECTORY


                                                 DEIATERING REGION
WATER LINE
u 1
k


LT~— HOTZTT-.:

'-*.'•>/"*
v O ^
1 •* ^
! i
oc oo oo oo

f
oo co oo oo x"
V


— , —

— \ 	 v3
I* 	
LECTRO CLEAR -BASIN
•v-> 00 ~3
PRESSURE
CELL
1 ,
J L
^ 	 	 '
J
^



                       Figure 11.   Schematic - electroflotation  and dissolved  air dewatering
                                    in same basin.

-------
       G.  Automatic pH control was used.  Dwell time in the pH adjustment
           tank is 4 minutes.  This chamber is also equipped with a mechani-
           cal mixer.  Both metal coagulant and sulfuric acid are added in
           this chamber.

       H.  At the insistance of management, turbidity control was installed.
           A Hach turbidity meter is used and, when turbidity is increased
           above a predetermined value, the treated wastewater is recycled
           to the holding tank for a second treatment.

       I.  The electroflotation basin contained 94 electrodes or 47 electrode
           pairs.   Approximately 1/2 of these electrodes were placed in the
           first quartile of the basin.  Their spacing  was 3/8 inch apart
           (surface to surface) and these were placed on polypropolene sad-
           dles 12 inches from the basin bottom.

       J.  Finally,  wastewater leaving the LectroClear  treatment operation
           was pH monitored on a recorder.  This  provides the needed records
           for its discharge.

 PERFORMANCE OF THE INSTALLED LECTROCLEAR-Z-M UNIT

 Operating conditions of the wastewater treatment plant are as follows:

       A.  Electrocoagulation cell - 1500 amperes at 12.5 volts.

       B.  Electroflotation basin - 1400 amperes  at 12.8 volts.

       C.  Dewatering unit  employed 35 percent recycle  at 55 psi gauge with
           a retention time of 4 minutes in the pressure chamber.

       D.  Wastewater flow  - 1.14 M^ (300 gallons)  per  minute, pH 4.5.
           Analysis  of wastewater leaving the LectroClear-Z-M unit is given
           in Table  6.   These analyses consist of 4-hour composites taken
           on two  consecutive days.

       E.   Chemicals  added  are:

            1.   1200  mg/lt  sulfuric  acid  66°  Be.

           2.   100 mg/lt alum.

           3.   6 mg/lt anionic  polymer  (X-400).

           4.   pH -  4.4 to  4.8.

Determination of solids content  in  the  skimmings showed  the  following:

      A.  Lowest solids obtained -  13.7%.

      B.  Highest solids obtained - 17.5%.

Skimmings volume equaled between 4 and  7 volume percept  of  the wastewater
treated.
                                     284

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   TABLE 6.  PERFORMANCE OF LECTROCLEAR-Z-M (pH 4.5) AT RENDERING PLANT
Treatment
Run 1
Influent
Effluent
Run 2
Influent
Effluent
Run 3
Influent
Effluent
Alum
mg/lt
100


100


100


H2S04
mg/lt
1200


1200


1200


Polymer
mg/lt
6


6


6


BOD
Total
mg/lt
7800
3850

6800
2200

8800
3400
BOD
Soluble
mg/lt

4800
3800

2100
2000

3500
3200
SS
mg/lt
4475
95

3200
110

2860
80
FOG
mg/lt
800
15

850
20

780
22
Protein*
mg/lt

1080
410

1100
385

990
340
* Nitrogen value x 6.25.
                                      285

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 DISCUSSION

 The  described  plant  was  designed  to  provide  effluent wastewaters with less
 than 200  mg/1  of  suspended  solids and  less than  100 mg/1  of hexane extract-
 ables.  The  fact  that  the plant in reality produced results much better
 than these is  primarily  attributed to  the unique combination of a two-step
 primary treatment combined  with a dissolved  air  skimmings dewatering unit.

 Based on  the unusually good results  obtained by  this design, it follows
 that the  plant wastewater can  be  effectively treated by using only a tri-
 valent  metal coagulant or by using a combination of sulfuric acid and tri-
 valent  coagulant.  The actual  chemicals  used will depend  to some degree on
 the  objectives of the  plant.

 In summary,  a  new dimension has been established in the wastewater treatment
 technology of  rendering  plants.   This  technology incorporates the following
 three factors  in  one operation.

      A.   Operates in  the close vicinity of  the  zero zeta potential by the
           use  of  pH adjustment with  sulfuric acid.  This condition yields
           skimmings which are  more easily renderable.

      B.   The  operation  employes  a sequential two-step technology (coagula-
           tion cell plus flotation basin) where  higher efficiencies are
           achieved in  the removal  of fats and oils and suspended solids.

      C.   The  technique  of  dewatering  skimmings  with the use of dissolved
           air has  the  advantage of not requiring additional space, pro-
          viding  skimmings with a  higher solids  content and, lastly,
           removing additional amounts  of the suspended solids in the waste-
          water as it  passes through the dewatering section of the flotation
          basin.

CONCLUSIONS

The conclusions are based on wastewater from a particular rendering plant.
Logic would say that they would apply  to most rendering plants.

 1.   The average surface charge (streaming potential) on pollutants in the
     rendering wastewater evaluated approaches zero at pH of about 4.2.
     (See Figure 1.)

 2.   The combination of sulfuric acid,  a trivalent metal cpagulant,  and a
     polymer  provide for the most  cost effective treatment.   Due to the high
     buffer action of  the rendering wastewater at the plant  in question,
     unusually large amounts of sulfuric acid are needed.   (See Figure 2.)
                                     286

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3.  From a practical sense, the problem of treating the wastewater to meet
    predetermined effluent standards is just the beginning of the overall
    wastewater treatment problem.  Such factors as cost effectiveness, odor
    caused by treatment, properties of the skimmings  (renderability), and
    disposal of the skimmings are all integral parts  of the wastewater
    treatment operation.  The above are closely interwoven with correspond-
    ing plant costs.  More often than not, simply providing treated waste-
    water with low suspended solids and fats and oil  values will not
    adequately satisfy overall plant environmental conditions.

4.  The use of a two-step primary treatment using a coagulation cell is
    especially effective in removing suspended solids and fatty materials
    from rendering wastewater.

5.  The use of a dissolved air dewatering operation in the flotation basin
    itself is especially suitable and effective because it requires no
    added space for the dewatering operation.  It also lowers the suspended
    solids in the effluent wastewater.
                               REFERENCES
1.  Beck, E. C., Giannini, A. P., and Ramirez, E. R.  Electrocoagulation
    clarifies food wastewater.  Food Technology, Vol. 28, No. 2, pp. 18-22,
    1974.

2.  Ramirez, E. R.  Electrocoagulation clarifies food wastewater.  Deeds &
    Data, Water Pollution Control Federation, April 1975.

3.  Ramirez, E. R.  Dewatering skimmings and sludges with a Lectro-Thic
    unit.  Presented at WWEMA Industrial Pollution Conference, Chicago,
    April 2, 1975.

4.  Ramirez, E. R., Johnson, D. L., and Clemens, 0. A.  Direct comparison
    in physiochemical treatment of packinghouse wastewater between dis-
    solved air and electroflotation.  Delivered at 31st Annual Industrial
    Waste Conference, Purdue University, West Lafayette, May 4-6, 1976.

5.  Ramirez, E. R., Barber, L. K., and Clemens, 0. A.  Primary physio-
    chemical treatment of tannery wastewater using electrocoagulation.
    Presented at 32nd Annual Industrial Waste Conference,-Purdue Univer-
    sity, West Lafayette, 1977.

6.  Ramirez, E. R., Johnson, D. L., and Elliott, T. E.  Removal of sus-
    pended solids and algae from aerobic lagoon effluent to meet proposed
    1983 discharge standard to streams.  Presented at 8th National Sympo-
    sium on Food Processing Wastes, Seattle, March 31, 1977.
                                    287

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                  PROTEIN RECOVERY FROM MEAT  PACKING EFFLUENT

                                      by

         D.  E.  Hallmark*,  J.  C.  Ward**,  H.  C.  Isaksen***, W. Adams****
 INTRODUCTION

 This  report describes  the  Sterling  Colorado Beef Company Alwatech protein
 recovery plant which is  the  first Alwatech recovery plant installed in
 the United  States.

 The Alwatech process is  used for the reclamation of high energy, high
 quality  protein  concentrates from the  fresh effluent wastewaters of fish,
 meat,  and poultry processing plants.   Recovery of saleable protein materials
 and simultaneous reduction by 60-90% of the pollution load (B.O.D.) of
 plant  wastewaters are  the  dual objectives of this process.

 The Alwatech process uses  lignosulfonic acid (LSA) precipitation and dis-
 solved air  flotation for recovery of the protein concentrate for an animal
 food material.  A 4% concentration  of  LSA as an energy source and/or pellet
 aid is authorized in mixed feeds, liquid feeds, and flaked grains in many
 countries (1) (2) (3).  The  Alwatech plant operation at Sterling Colorado
 Beef Company is currently  being optimized.

 BACKGROUND

 Historical Development

 The basic research work leading up  to  the Alwatech process was started
 in Oslo, Norway as early as  1960.  At  that time Leif Jantzen et. al. (3)
 developed a method for separating pure high molecular weight ligposulfonate
 (LSA)  from sulphite liquor,  and during studies of the properties of pure
 LSA, the ability of LSA to precipiate  soluble proteins from dilute aqueous
solutions was found to be a very promising application.
   * Donald Sutherland Associates, Inc., Denver, Colorado
  ** Professor at Colorado State University, Fort Collins, Colorado
 *** Alwatech A.S., Oslo 2, Norway
**** Sterling Colorado Beef Company, Sterling, Colorado

   0 Data collection and evaluation of the Sterling Colorado Beef Company
     Alwatech plant is being conducted under an EPA demonstration grant.
                                    288

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Additional studies of the LSA precipitation of proteins resulted in a
patented method.  On the basis of this patented method, Alwatech was
started in 1965 as a member of the Apothekernes Laboratorium for Special
Preparater A/S  (AL Group of Companies) of Norway.

Alwatech developed an industrial process using LSA precipitation of pro-
teins for the treatment of wastewaters and recovery of proteins from abat-
toir, fish, and poultry plants.

Alwatech's early years of research and development were followed by the
installation of plants in many countries and industries.  Alwatech operates
internationally, with subsidiaries and resident technical offices in a
number of countries, including the United Kingdom and the United States.

Dissolved Air Flotation

Dissolved air flotation (DAF) has performed well for many years in the
treatment of wastewaters.  DAF is based on the fact that air is soluble in
water in direct proportion to the pressure applied.  When the pressure is
released under the proper conditions, the air comes out of solution in the
form of tiny bubbles.  If a pressurized solution of contaminants, water, and
air is agitated, and if the solution is released into an open vessel, the
bubbles and solids will combine and float to the surface due to their reduced
combined specific gravity.  Then the float can be skimmed off of the
surface.

Before DAF could be used productively by industries with high protein
wastes, it was necessary to develop a means by which nutrients could be
recovered from wastewaters at a low cost, biochemical oxygen demand (BOD)
could be reduced, and dilute fats could be cheaply separated.  Researchers
have reported on a variety of chemicals that can be added immediately pre-
ceding the DAF process to achieve some or all of the above objectives.
Barnett and Nelson (4) and D. B. Ertz et. al. (5) studied the effects of
adding Al2(S04), and Ca(OH)2, to the wastewater produced in the seafood
processing industry.  However, the above authors were solely concerned
with meeting water quality standards and not with recovering an animal
food product.

Wayne A. Bough et. al. (6), on the other hand, reported on a chemical which
potentially could satisfy all the objectives.  In their paper, the authors
demonstrated the efficacy of chitosan, (an organic polymer composed of
glucosamine residues) in producing a nutritious animal feed from wastewater.
Although chitosan would appear to satisfy the needs of a number of indus-
tries with protein rich wastewaters, FDA approval is pending.

Thus, at the present time, the only chemical additive that can economically
recover nutrients from effluent is lignosulfonic acid.  This use of LSA
was developed by Alwatech A/S, of Norway, and is marketed under the trade
name of Alprecin in Europe.  Because the Sterling Colorado Beef Company
is the first company in the United State to incorporate the Alwatech
process, the following discussion is particularly relevant for U.S. firms.
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          GENERAL DESCRIPTION  OF  THE ALWATECH PROCESS USING ALPRECIN

 The Alwatech process  is  a  unique patented system for the recovery of a
 dry saleable meal from abattoir, poultry packing, and fish processing
 wastewaters.   The process  also treats  these wastewaters to the point where
 they can be  discharged into municipal  sewers.

 The Alwatech process  is  based upon the specific precipitation of proteins
 (7)  by  purified  high  molecular weight  lignosulphonates (ALPRECIN), under
 acid conditions.   Lignosulphonates are chosen because, unlike alternative
 chemicals, they  can precipitate  dissolved blood, and they are accepted
 as  animal feed additives by both the European Economic Community and the
 Federal Drug Administration.

 The  high molecular weight  lignosulphonate is derived from sulphite lye,
 a by-product  of wood  pulping, from which the major part of the carbohy-
 drates,  in themselves  a  source of pollution, has been removed.

 The  process wastewater from abattoirs, poultry packing plants, and fish
 processing industries  exhibits a varying flowrate and will contain large
 amounts  of suspended  solids in addition to dissolved and emulsified fat
 and  proteins.  It  is  recommended that  screening and a balancing tank be
 used to  reduce surges  in flow and quality.

 To obtain the  maximum  benefit of the protein recovery and effluent treat-
 ment  ability of the Alwatech process,  it is sometimes advantageous to let
 some  particular streams  from a slaughterhouse undergo separate pre-treat-
 ment  or  by-pass the Alwatech plant altogether.   Examples of^ the first kind
 is tripe wastewater and  of the latter  cattle pen wastewaters.   Minimum
 balancing capacity is  normally equal to 1/2 to 1 hour flow, depending on
 the production rate at the site.   If a larger balancing capacity is installed,
 however,  the plant operating hours may be extended up to 24 hours per day.

 After screening, the equalized flow of wastewater is precipitated with puri-
 fied high molecular weight lignosulfonic acid at a pH of approximately 3,
 the pH being reduced with sulphuric acid.   Before the treated  effluent
 is discharged into the sewer, or a subsequent biological treatment system,
 it is neutralized  to a pH between 6 and 8 with calcium hydroxide or
 another base such as sodium hydroxide.

Following precipitation,  the floe,  which contains protein,  fat, and sus-
pended matter, is separated by dissolved air flotation.

From a typical wastewater with a BOD of 1,000 to 2,500 mg/1 before any
 treatment, the Alwatech process normally produces an effluent  of the
following quality:

                BOD                       70 - 80% reduction
                Suspended Solids           less than 300 mg/1
                Fat                       less than  75 mg/1
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 The concentration  of  the  sludge as removed from the flotation system is
 normally 6  -  12% solids depending largely on the origin and pre-treatment
 of the process wastewater.

 The sludge  removed from the flotation tanks is neutralized with calcium
 hydroxide.  At the same time, surplus or diluted blood may be added.

 After neutralization, with or without blood, the sludge is processed through
 a coagulator  to a  filter  belt for dewatering.  A decanter (centrifuge)
 may also be used for  dewatering.

 The sludge  will contain 30-50% solids after dewatering depending on the
 dewatering  system  used.

 The water removed  from the sludge in the dewatering process may contain
 up to 40% of  the original lignosulphonate added in the chemical treatment
 process.  In  large installations, a lignosulphonate recirculation system
 is installed  to reduce chemical consumption.

 The concentrated (30-50%  solids) sludge may be dried in a rendering plant,
 mixed with  other by-products, or dried in a separate drier.

             THEORY OF PRECIPITATION WITH LIGNOSULPHONIC ACID (LSA)

The theory of LSA precipitation was reported by T.  R.  Foltz,  et. al's (7),
and is quoted below:

     "The precipitation of soluble protein with soluble lignosulphonic acid
     in an acidic aqueous system is believed to be  a nearly instantaneous
     reaction involving the negatively charged sulphonate groups on LSA
     molecules and positively charged amine groups  present on the protein
     molecules.   The complexing of these large molecules results in a
     gelatinous suspended material that can be removed by a suitable physical
     liquids-solids separation technique.

     "Protein molecules contain both positively charged amine groups and
     negatively charged carboxyl groups when the solution is  at pH values
     near 7.  Acidification of proteinaceous waste  water to pH values below
     the isoelectric point will result in proteins  carrying a net positive
     charge.  Isoelectric values vary with different proteins, but acidifica-
     tion to 3.5  or below normally insures a pH below the isoelectric for most
     protein solutions.

     "Lignosulphonic acid when in solution has the  sulphate group essentially
     completely ionized,  resulting in a net negative charge on the LSA
     molecule.  With acidification,  the strong acid group of  the sulphonate
     continues to carry a negative charge even at pH values of 2 to 3.  At
     extremely low pH values below 1,  the sulphonate group begins losing its
     charge."

     "Table I summarizes the respective net charges on LSA and protein mole-
     cules at various pH ranges, noting the resulting precipitation potential.

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Table  1
INFLUENCE OF pH ON LSA - PROTEIN PRECIPITATION.
pH Range

 0-1
 2-3
 3.5 - 4.5

Above 4.5
  Protein

  Positive Charge
  Positive Charge
  Isoelectric
  (no net charge)
  Negative Charge
LSA

Weak Negative Charge
Negative Charge
Negative Charge

Negative Charge
Precipitation

Poor
Good
Poor

None
     "This table reveals that the pH must be in range of 2-3 to obtain
     effective precipitation.  Actual experimental evidence confirms that this
     is the optimal pH range for precipitation of the maximum amount of
     protein.

     "Because the precipitation involves balancing of opposite ionic charges,
     it follows that an optimal ratio exists between LSA and proteins in order
     to maximize protein removal with the least amount of LSA.  Experimental
     evidence also confirms that treament of proteinaceous wastes with LSA
     is quantitative, making LSA dose control important.

     "In precipitating and removing the LSA and protein complex, fat and fatty
     material (as determined by hexane soluble extraction) are also largely
     removed.  In raw waste, fat is primarily particulate and emulsified matter
     with a free fatty acid content ranging from 5 to 50 per cent of the total
     fat content.  Acidification of raw wastes eliminates the strong negative
     charge on the free acid carboxyl groups resulting in a loss of water
     solubility.  Therefore, at protein precipitating pH values, most of the
     fat material tends to separate from the water and float to the surface.
     The presence of LSA would not be expected to enhance fat removal if
     protein matter was absent from the raw wastes.

     "With protein present and forming an insoluble material with LSA, the
     fat tends to be comingled with the protein LSA material."

          THE USE OF ALWATECH RECOVERED PROTEIN CONCENTRATE AS ANIMAL FEED

 The Alwatech Protein Concentrates

 The composition of these protein concentrates is dependent primarily on
 the sources of the raw material and the components of the effluent treated.
 From fish and meat sources which have been the most investigated and uti-
 lized to date, high quality components are assured because the material
 is dominantly muscle, blood, and fat.

 Flesh particles, dissolved blood, and released fat are treated within ap-
 proximately 1-2 hours at pH 3 so that the freshness and bacteriological
 condition of the raw material is excellent and superior to many other by-
 product animal foodstuffs.
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  The LSA concentration  in  the dry matter of the protein concentrates may
  vary from 5  -  15% but  is  normally about 10%.  The following tables show
  typical analyses of Alwatech protein concentrates recovered from waste-
  waters  in the  fish and meat industry.

  An illustrative average analysis of the Alwatech herring protein concen-
  trate is comparable with  commercial herring meal with due allowance for the
  LSA content  (Table 2).
Table 2	COMPARISON OF RECOVERED PROTEIN WITH HERRING MEAL.	
                                                            Alwatech herring
                                        Commercial          protein
                                        herring meal,%      concentrate, %
Crude protein (organic nitrogen x 6.25)
Fat
Calcium
Phosphorus
Sodium
LSA
69
8
4.8
2.8
1.4
0
71
9
4.7
2.8
1.6
10
Table 3      ANALYSIS  OF A SAMPLE  OF MATERIAL  RECOVERED  BY THE ALWATECH PROCESS
	AT  KBS. SWEDEN (PRIMARILY PORK SLAUGHTERING).	
                            %
Protein                 -   56.0
Oil                     -   15.0
Fiber                   -    2.5
Nitrogen Free Extracts  -   20.0
Ash                     -    6.4
The amino-acid composition of the protein in Alwatech protein concentrate
meals has been determined for products obtained from fish and blood processing
(1).  It may be seen from Table 4, that the composition is unaffected by the
LSA treatment.  This would be the expected result from conventional acid
precipitation of proteins extensively studied including fish, egg, soya,
groundnut, and casein whose amino-acid composition is altered only by virtue
of loss of certain components in the mother liquor, (i.e. non-precipitated
fraction) and not by precipitation as such.
                                     293

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Table 4
AMINO-ACID COMPOSITION OF PERCENTAGE CRUDE PROTEIN.

                 Fish
                    Untreated
                     LSA
                     Precipitated
                                                             Blood
Untreated
LSA
Precipitated
Cystine
Aspartic acid
Methionine
Threonine
Serine
Glutamatic acid
Glycine
Alanine
Valine
Isoleucine
Leucine
Tyrocine
Phenylanine
Lysine
Histidine
Arginine
1.0
9.0
3.2
4.6
4.1
14.1
5.6
6.3
5.6
4.7
6.9
2.1
3.6
7.3
2.2
5.0
1.1
9.0
3.4
4.7
4.0
14.5
5.5
6.2
5.1
4.4
6.6
2.2
3.8
7.2
2.2
5.3
0.9
9.4
2.9
4.6
4.5
13.6
7.4
6.7
5.0
4.7
7.3
2.9
4.0
8.2
2.4
6.0
0.9
8.7
2.9
4.4
4.2
13.2
7.3
6.5
4.9
4.3
7.3
2.3
3.9
7.8
2.2
6.0
The digestible protein determined by the pepsin-hydrochloric acid method
showed that the feed value of proteins precipitated with lignosulphonates
is only 15-20% lower than for equivalent unprecipitated blood meal.  This
must be considered as an unexpected good result because it is known from the
works of B. Naess (8) that lignosulphonates have an inhibiting effect on
pepsin under acid conditions.

In the trypsin system, however, there is no such inhibiting effect, and to
determine the complete feed value it is necessary to include the Trypsin
method.  Moreover, it was found that protein precipitated by ordinary
sulphite lye had a lower feed value than protein precipitated by Alprecin.

                     PROTEIN QUALITY AND FEEDING TRIALS

LSA is a purified derivative from wood pulping liquors which has been
fed extensively to many animal species for many years in dried form.
Extensive tests under controlled conditions reported in 1973 (9) show that
relatively high levels of sulphite liquor concentrates in animal feed
does not affect feed conversion.

The harmless nature of LSA in rat and poultry feeds has been borne out in
feeding tests of protozoa, rats, and chickens to determine the protein
quality and feeding value of Alwatech protein concentrates.  Up to 4%
of crude LSA as an energy source and/or pellet binder is authorized in
mixed (compound) feeds, liquid feeds, and flaked grains in many countries
with a wide range of feeding practices and ration formulations (2).
The products contain 60% lignosulphonate, which implies a safe level in
                                    294

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 feed stuffs of 2.5% LSA or  less.   This is above the anticipated inclu-
 sion rate in feeds from Alwatech  protein concentrates of which a relatively
 small tonnage would be available,  compared with the quantity of other
 protein and energy ingredients  in farm animal diets.

 Provided normal and conventional  practices in the drying of protein pro-
 ducts from industrial processes are followed, protein quality should be
 equivalent to that of the starting material.  Indeed blood proteins, fish
 solubles or by-product fats,  for  example, probably receive longer and pos-
 sibly more severe  drying conditions than Alwatech protein concentrates.

 In the abattoirs and meat packing industry,  the recovered material can be
 added to renderable material  for  production  of meat-bone meal and techni-
 cal fat,  or dried  separately.   A  number of feeding trials with Alwatech
 recovered protein  concentrates  show that the feeding values of the recovered
 material are comparable with  existing market qualities and that substi-
 tution of up to 50% in fish meal  or soya bean meal feed mixture with Alwa-
 tech protein concentrate (APC)  does not affect live-weight gain, feed con-
 version ratio,  or  mortality.

 Poultry feeding trials have been  carried out as chicken growth tests (10),
 poultry screening  tests and pelleted feed tests.

 Table 5 shows a typical result  obtained by three groups of 510 chicks
 on a diet containing 22% crude  protein where the APC content is substi-
 tuted for herring  and soyabean  meal.


 Table  5RESULTS OF CHICK FEEDING TRIALS.
                                        Herring      APC      APC
                                          4%          4%       8%
Mortality
 0-7 days                               35          22       34
 8-49 days                              13           68
Live-weight gain
50 days (g)                             1270        1290     1311

Feed conversion ratio	2.13   	2.10	2.05	

Pig feeding trials have been conducted with addition of LSA in amounts of
3% and 12% of  the feed (11) with the Alwatech protein concentrates sub-
stituted for parts of or all of the soyabean meal in the diet.  These
pig feeding trials show that the LSA content in feed can be up to 6%
and that 50% of the soyabean meal can be replaced by Alwatech protein
concentrate without any significant effect on live-weight gain, feed con-
version, or mortality.
                                     295

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            DESCRIPTION OF THE ALWATECH PROCESS  INSTALLED AT  STERLING
                         COLORADO BEEF COMPANY (SCB)

 Plant Capacity

 This effluent protein recovery system has been  designed  to treat up to
 3,000 cubic meters per day (800,000 gpd)  of wastewater containing 4,100
 kilograms (9,000 pounds)  of BOD5 and 5,400 kilograms  (12,000 pounds) of
 suspended solids over 16  hours.   At this  BOD5 loading, the nominal capa-
 city of the effluent treatment plant is 200 cubic meters  per hour (52,000
 gph).

 Table 6 shows the current loading at the  balancing tank  of the Sterling
 Colorado Beef Company packing plant.  The test  data presented are based
 on 4-hour composite samples.
 Table  6.   CURRENT  WASTEWATER CHARACTERISTICS AT SCB.
 BOD5, mg/1
 COD, mg/1
 Suspended Solids, mg/1
 Oil and Grease, mg/1
 Flow, gpd
 Beef processed, head/day
 Average live weight, pounds
Minimum

 1,500
 2,200
   740
   320
 Average

  2,274
  3,572
  1,825
  1,140
513,500*
  1,750
  1,031
Maximum

 4,900
 6,320
 2,650
 4,040
   * This flow rate is the average treated through the Alwatech plant during
     preliminary testing and does not reflect the total water used at
     Sterling Colorado Beef Company.
The plant has been designed to remove 70% of the applied BOD load, reduce
the suspended solids to less than 300 mg/1, and reduce oil and grease to
less than 75 mg/1.

It is estimated that the plant will recover approximately 4,500 kilograms
(10,000 pounds) of dry solids per day from dewatered sludge containing
60 - 70% moisture.  The dewatered sludge has less than 10% fat on a dry
weight basis.  Tests have demonstrated that it can be dried in the existing
rendering plant.  It is possible that a separate drier could be used for
the recovered product.  The plant layout is shown in Figure 1, and Photo 1
shows the building that contains the Alwatech plant.
                                     296

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FIGURE I  - STERLING  COLORADO BEEF  COMPANY
            ALWATECH  PLANT  LAYOUT

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 Photo  #1  - Alwatech building at Sterling Colorado Beef Company,
           Sterling, Colorado.

 Wastewater Pre-Treatment

 SCB has approximately 1,500 cubic meters per day (400,000 gpd) of process
 wastewater from  the slaughtering operations with a BOD5 of 1,600 to 1,800
 mg/1 after screening.  The wastewater is screened through a rotating
 screen at the rate of 120 cubic meters per hour (30,000 gph) before being
 discharged to a  300 cubic meter (80,000 gallon) circular clarifier equipped
 with a bottom scraper.  The clarifier has provisions for removal of float-
 ing fat (grease).  Solids removed by the screen and from the surface of
 the clarifier are returned to rendering.

 The clarifier, which was present prior to installation of the Alwatech
 plant, is now used as a combined clarifier and balancing tank.  During
 the day the level in the clarifier is kept 15 to 30 cm below the overflow
weir for  grease removal while it is pumped 2.5 m (8 feet) down each even-
 ing.   The night wastewater from the slaughterhouse is allowed to fill up
 the clarifier again overnight.  Solids settled out in the clarifier are
 removed at regular intervals for recovery or deposited off site.

Approximately 65 cubic meters per day (17,000 gpd)  of highly polluted
effluent with a pH between 11 and 12 is discharged from the tripe washing
department.   This effluent is screened on a rotating screen before being
discharged to the clarifier.   Alternatively,  the screened wastewater may
be pumped to the Alwatech plant bypassing the clarifier.   Solids removed
by the screening operation are returned for rendering.

Blood  coagulation is done in-line with live steam.   Coagulated blood is
separated on a shaker screen.  The effluent originating from the dewatering
of blood has a very high BOD and contains valuable suspended solids.
This effluent is pumped to a settling tank and thereafter pumped directly
                                    298

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to the Alwatech plant bypassing the clarifier.
to the Alwatech sludge dewatering system.
Settled solids are pumped
Sterling Colorado Beef Company has direct contact condensers in the ren-
dering plant which discharge approximately 750 cubic meters per day
(200,000 gpd) of condenser water at a temperature of 80°C (175°F).   This
particular wastewater contains very little fat or proteins for recovery
in the Alwatech effluent treatment system.  It has a BOD generally  below
the BOD level discharged from the Alwatech plant.  Tentative plans  are to
discharge this effluent to the sewer.

Cattle pen wash water is screened on a shaker screen and discharged to
two settling tanks in series.  At present this wastewater bypasses  the
Alwatech system.  SCB has approximately 70 cubic meters per day (18,000
gpd) of cattle pen wash water and after screening and settling it contains
approximately 2,400 mg/1 BOD.

All effluents from preparation of hides are discharged separately and are
not treated in the Alwatech plant.

It is desirable to bypass the clarifier (balancing tank) with particular
waste streams such as those from tripe operations and cattle pens,  to reduce
biological action in this tank.  Biological activity in this tank has been
found to reduce the protein content of the final product.
Photo #2 - DAF tanks being installed at SCB.
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Alwatech Process Flow Description

Figure  2 is  the Alwatech process flow diagram of the Sterling Colorado
Beef Plant.  The incoming wastewater is pumped by feed pumps M3 and M4
from the clarifier to flotation tanks I and II (See Photo 2).  Before this
wastewater enters the flotation tanks, LSA, H2S04, and water (partly satu-
rated with air) are added.  LSA, which is delivered as a powder, is dis-
solved  in water to a concentration of 10 to 15%.   A dosing pump M6, ad-
justable from the control panel, delivers the needed quantity of LSA solu-
tion.   H2S04 is taken directly from a storage tank and diluted with waste-
water before being added to the 2 flotation tanks.  The H2SC>4 is pumped
by dosing pump M5 which is automatically controlled by the pH I equipment
which utilizes electrodes that are cleaned ultrasonically.

Water,  partly saturated with air, is produced from a mixture of water and
wastewater by means of high pressure pumps Ml and M2, injectors, and pres-
sure vessels I and II (See Photo 3).  The treated effluent is neutralized
with Ca(OH)2 and is dosed by the neutralization dosing screw M19 (in the
Lime Silo) which is controlled by pH II equipment (See Photo 4).

The protein sludge is removed from the surface of the 2 flotation tanks
and pumped by flotation pumps M10 and M13 to the 3 sludge treatment tanks.
Bottom  sludge is removed from Flotation Tanks I and II by bottom scrapers
M16 and M17, respectively, and pumped to the 3 sludge treatment tanks by
bottom  sludge pump M18.   Sludge pumps M29 and M30 pump the protein sludge
to heat coagulators I (M31) and II (M32), respectively (See Photo 5).
Dewatering on Filterbelts I (M33) and II (M34) produces a combination
protein fat concentrate containing approximately  40% dry matter (See Photo 6)
Reject pumps M35 and M36 pump the liquid from the 2 filter belts to the
flotation tanks influent line.  The Alwatech process is controlled from a
central panel containing the automatic equipment  (See Photo 7).

Sludge on the bottom of the clarifier is pumped to the settling tank by
sludge pump M37.   Sludge pump M38 moves this concentrated sludge to the
3 sludge treatment tanks.
                                   300

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                            	   COLORADO  BEEF  COMPANY
                             ALWATECH PROCESS CONTROL BOARD
Co
O

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Photo #3 - Air Injection Pressure Chambers at SCB,
    Photo #4 - Lime Neutralization Tank at SCB.
                       302

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Photo #5 - Coagulators and Filter Belts for Sludge Drying at SCB.
        Photo #6 - Sludge Tanks and Filter Belts at SCB.
                               303

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Photo #7 - Electrical Control Center for the Alwatech Process,
                             304

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                                    REFERENCES
 1.  G. D. Rosen, Safety and Quality Considerations on Protein Concentrates
     Manufactured by the Alwatech Process, unpublished report.

 2.  American Paper Institute, 1958 Food Additives Amendment,  Release 14,
     May 16, 1970, Regulation No. Sec.  121.234, Fed.  Doc. 70-6436,  Filed
     1970.

 3.  Jantzen, L., "Protein-Rich Feed Material and Method of Making," U.S.
     Patent No. 3,390,000 (July 2, 1968).

 4.  Barnett, H. J. and Nelson, R. W.,  "A Preliminary Report on Studies
     to Develop Alternative Methods of  Removing Pollutants from Tuna Pro-
     cess Wastewaters," Proceedings of  the Sixth National Symposium on Food
     Processing Wastes. EPA-600/2-76-224 (1976).

 5.  Ertz, D. B., Atwell, J. S., and Forscht, E. H.,  "Dissolved Air Flota-
     tion Treatment of Seafood Processing Wastes — An Assessment," Pro-
     ceedings Eighth National Symposium on Food Processing Wastes.   EPA-
     600/2-77-184 (1977).

 6.  Bough, W. A., Landes, D. R., Miller L.,  Young, C. T., and McWhorter,
     T. R., "Utilization of Chitosan for Recovery of Coagulated By-Products
     from Food Processing Wastes and Treatment Systems," Proceedings of
     the Sixth National Symposium on Food Processing Wastes, EPA-600/2-76-
     224 (1976).

 7.  Foltz, R. R.  Jr., Ries, K. M., and Lee,  J. W. Jr., "Removal of Protein
     and Fat from Meat Slaughtering and Packing Wastes Using Lignosulfonic
     Acid,"  Proceedings Fifth National Symposium on Food Processing Wastes,
     EPA 660/2-74-058 (1974).

 8.  Naess, B., Westbye, 0., Hildrum, K. I. and Nafstad, I., "The Effects
     of Peptide-Precipitating Lignosulphonic Acids on the Proteolytic
     Activity of Pepsin In Vitro, and on the Response of Pigs  to an Ulcer
     Inducing Diet," Effects of Sulphite Spent Liquor Components on Some
     Biological Systems, Universitetsforlaget, Oslo,  1972.

 9.  Klopfenstein, T., Koors, W., Farlin, S., Nebraska Beef Cattle  Report,
     1973.

10.  Herstad, 0. and Hvidsten, H., Protein Recovered from Industrial Waste
     Water as Feed for Chicks, Department of Poultry and Animal Science,
     Agricultural University of Norway, AS-NLA, Norway.

11.  Naess, B. and Fjolstad, M., "The Effect of Feeding Peptide Precipi-
     tating Lignosulphonic Acids in Various Concentrations to Growing Pigs,"
     Effects of Sulphite Spent Liquor Components on Some Biological Systems,
     Universitetsforlaget, Oslo, 1972.


                                     305

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                    A METHOD OF PHYSICO-CHEMICAL TREATMENT
                           OF ORGANIC WASTEWATERS

                                     by

                               P. Stephenson*
ABSTRACT

A process to treat organic wastewaters containing significant concentrations
of protein and grease is described.  Special reference is directed toward
the treatment of meat packing plant effluent as it is for this application
the majority of process data is available.  Development is traced from
initial effluent characterisation and experimentation, through pilot plant
trials to preliminary full scale evaluation.  Particular importance is
attributed to the recovery of useful by-products and their application as a
feed supplement for non-ruminant animals.  In one instance treatment of a
meat packing plant effluent, as discharged after primary treatment in a
saveall or catch basin, resulted in 75-80% removal of chemical oxygen demand.
Broiler grower chicken feeding trials using the by-product recovered from
this treatment showed comparable growth to similar inclusions (0-14%) of
conventional Meat and Bone meal supplements.

INTRODUCTION

The high organic content of many industrial wastewaters, especially those of
the food processing industries, results in a considerable biochemical oxygen
loading to effluent treatment plants and natural waterways.  In the meat
industry protein and grease bearing effluents, even after primary treatment
to remove the bulk of floatable and settleable solids, are typically an
order of magnitude stronger (based on 8005) than domestic wastewater.

For a typical New Zealand meat packing plant with an average wastewater flow
of 6750 m^/d (1.76 mgd (U.S.)) and, mean total organics concentration, after
the removal of bulk solids in a saveall or catch basin, of 1800 mg/1 the
daily organic solids discharge would amount to approx. 12,150 kg/d.  The
significance of a suitable method of treatment and the potential for
by-product recovery is therefore apparent.
*Morrison, Cooper and Partners, Ghuznee St., Wellington, New Zealand.
 Currently at Graduate School, McMaster University,  Hamilton,  Ontario,
 Canada.
                                     306

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The Application of Physico-Chemical Processes

An intelligent approach to the selection of any treatment process initially
involves characterisation of the wastewater over a significant time period
and an assessment of the degree of treatment required for that particular
plant location.  Previous applications have involved partial treatment of
sewage effluent by lime precipitation and acid cracking of wool scour effluent.

In general physico-chemical treatment systems are considered expensive in
comparison with many biological treatment processes such as anaerobic
lagoons.  However when physico-chemical treatment permits the recovery of a
valuable by-product and or water for reuse the project economics may be
more favourable.  This is especially so in urban localities where water and
sewage charges are applicable and available land for the treatment plant is
limited.  Additional advantages include the adaptability of some systems
to input effluent composition fluctuations and toxic environments, both of
which significantly affect biological process performance.

Background to the Process Development

Initial studies in 1968-69 at the N.Z. Department of Scientific and Industrial
Research on the application of regenerated cellulose based ion exchange resins
for the removal of proteins and charged organic groups "from meat packing plant
effluents indicated that a pretreatment to remove high levels of grease and
suspended solids was necessary to prevent resin fouling.  It was also
considered desirable to reduce the protein concentration to levels more
attune to practical separation by ion exchange (max. 300-400 mg/1 protein).

The pretreatment performance required was beyond that achievable by any form
of mechanical screening, and biological processes affected a complete change
in effluent composition.  Thus a number of chemical treatment processes were
investigated to remove the majority of effluent organics and produce an
effluent more amenable to ion exchange.

Extensive trials, both laboratory and pilot scale, since 1968 have progressed
to the stage where a reliable and efficient chemical treatment has been
developed for large scale application.  It is this process which is discussed
in this paper.  Throughout its development emphasis has been placed on a
process which incorporates:

     1.  Reliability to input effluent composition and solids loading
         fluctuations.
     2.  A sludge with good dewatering characteristics.
     3.  A maximum possible reduction in biological oxygen demand (BODs).
     4.  The production of valuable by-products and water for reuse.

The chosen process in reality represents a compromise of these features.
Its application to effluents from other food processing industries such as
fish and poultry has been successful and current investigations involve
the examination of its use in the treatment of a widespread range of organic
bearing industrial effluents, especially those with high concentrations of
protein and grease where by-product recovery is most likely.


                                     307

-------
 PROCESS DESCRIPTION

 In essence a chemical coagulation  process  is  employed  to  remove a major
 fraction of the organics  and suspended material  remaining after primary
 treatment.  The process involves a double  pH  shift with the addition of
 chemicals, resulting  in the formation  of a flocculated mass which is readily
 recovered and contains the  majority of organics  from the  effluent.

 The treatment process is  sequentially  summarised as follows:

 1.   Sulphuric acid  addition to  denature protein.  The  reaction proceeds in
     a stirred tank  maintained at a controlled pH corresponding to the
     isoelectric point of  the solution.

 2.   Coagulant addition to the acidified effluent.  The particular material
     selected will depend  upon the  process  performance  required and the
     proposed end use  of the byproduct.  In the treatment  of meat packing
     plant wastes a  phosphate coagulant  is  added  in the form of crushed
     superphosphate.

 3.   Neutralisation.   Stagewise  addition of a lime slurry  raises the pH and
     promotes further  coagulation.   The final stage is  controlled at the
     optimum pH for  flocculation.

 4.   A dilute flocculant solution is then added to the coagulated effluent
     and  is dispersed  under  controlled  hydraulic  conditions.

 5.   The  effluent is gently  agitated in  the  flocculation chamber of a
     flocculator-clarifier to promote the growth  of large, readily settleable
     floes.   Separation of these in  the  clarifier section  then produces an
     effluent  substantially  free of  suspended solids.

 6.   The  settled  solids are  thickened, heated, centrifuged and pneumatically
     dried.   Centrate  is recycled to the untreated wastewater inflow stream.

 The  optimal  chemical  dose rates and retention times at the various stages
 of  treatment  are a function  of  the  waste composition,  treatment requirements,
 and  engineering advantages.   For a  particular application these parameters
 are  determined on the basis  of  laboratory  and pilot plant studies.  By way
 of example  the most utilised  scheme, and that employed to treat meat packing
 plant wastes, is detailed in  Figure 1.

 TREATED EFFLUENT QUALITY

Process performance is a function of the untreated effluent characteristics.
Providing an  effluent contains significant concentrations of grease and
protein a  reduction in Chemical Oxygen Demand (COD)  of 75-80% may be expected
for  the coagulation process alone.    In general an increase in solids loading
and  influent' strength has resulted  in improved removal efficiencies and
greater by-product recovery,  thus reducing fluctuations in treated effluent
quality.  Almost complete removal of grease and suspended solids has been
achieved for  the treatment of many  effluents and Kjeldahl nitrogen reductions
in excess of 50% are typical.

                                     308

-------
u>
o
VO
SCHEft
MEAT
IATIC PROCESS FLOW DIAI
PACKING PLANT EFFLUEN
~~* Decapol A33 Flocculant
1 Hydrated Lime to PH 9.0
1 Superphosphate ( 200 mg/l)
1 Sulphuric Acid
! to pH 3.0
1
Plant
— *] Effluent
Cent rate
Recycle
HEAT
RECOV
, Direct Steam


ACIDIFICATION NEUTRALIZATION
dOmin) (5min)
Sludge Flow
|
\ fc . 	 ' fc
^"""•^1 	 •^— ^
t ' >
COAGULATION DECANTER
fERY (105°C) CENTRIFUGE
Injection ^
1 -
Fi
SRAM FOR CHEMICAL TREATMENT OF
T (as discharged from a Saveall )
PrrvaftB ^antion timo. tamponitiir««
and chemical dose rates are based on
Laboratory and Pilot Plant studies at 8
major meat packing plants in
New Zealand.
Treated
Effluent ^_
fc ^ 	 * , fc
oU ^:^^
FLOCCULATION SEDIMENTATION
(Smin) (overflow rate
2.45m3/m2hr)


~\ ^ Q-+ *~
/' V
.HT1!/ I Dried
W-T 1 By-product f-
RING Air W—
DRYER CYCLONE
gure 1

-------
 In Table 1  the process  performance  is  summarised for the treatment of
 protein and grease bearing wastes typical of New Zealand Meat Packing Plants,
 The figures tabulated are  based  on  data  recorded over a 4 year period of
 pilot plant and laboratory testing  on  site at 5 meat packing plants.

 Shown in Table 2 is the composition of the by-product recovered after
 treatment of the effluents described in  Table 1.
          TABLE  2.   COMPOSITION OF  THE BY-PRODUCT RECOVERED FROM THE
                    CHEMICALLY TREATED EFFLUENTS DESCRIBED IN TABLE 1

       By-Product                            Mean              „
                                            TT -•  j.            Range
       Component                             Value*

By-Product Total Solids                     1685            1200-2270
  Recovery (mg/1)

Ash Content  (%)                               25              23-30

Total  Grease  (%)                              27              15-35

Protein as NX6.25  (%)                         31              25-39

Other  Organics  (%)                            17              12-23

Composition  as evaluated on a dry wt. basis.


CHEMICALS AND UTILITIES

Chemical Treatment

Fluctuations  in effluent composition, buffering capacity, and solids loading
are common and result in variable acid and lime demand.  Coagulant and
flocculant dose rates may be constant and apportioned according to flow.

Typical treatment costs (April 1976) on a chemical usage alone basis are
shown  in Table 3 for a meat packing plant wastewater as discharged from a
saveall system used to remove bulk solids.  Figures 2 and 3 illustrate the
variability of acid and lime demand for the treatment of meat packing plant
effluent from the five plants with wastewater characteristics as described
in Table 1.

Utilities

Treatment plant power requirements vary with flow and composition, as these
effect the specific capacity of equipment.  However in the case of a meat
packing plant with a nominal effluent flow, from a saveall system, of
4500 m-Vd charges (April 1976) for labour, electricity, oil, and steam will
amount to approx. 5.8C (N.Z.)/m3 (22.0C/1000 U.S. gal.).  The basis for this
cost is shown in Table 4.
                                    310

-------
   TABLE  1.   PROCESS PERFORMANCE FOR THE CHEMICAL TREATMENT OF PROTEIN  AND  GREASE BEARING EFFLUENTS
             AFTER PRIMARY TREATMENT AT MEAT PACKING PLANTS IN NEW ZEALAND*
Effluent**
Component
Chemical Oxygen Demand (mg/1)
Total Solids (mg/1)
Suspended Solids (mg/1)
Total Organics (mg/1)
Ash Content (mg/1)
Total Grease (mg/1)
Protein as NX6.25 (mg/1)
PH
Untreated
Effluent
Mean Range
2765
2525
1235
1705
820
550
795
7.5
1570-3855
1960-4120
890-1960
1460-2010
250-2105
400-690
490-1170
7.1-8.8
Treated
Effluent
Mean Range
535
1855
60
700
1155
20
370
' 9.0
265-750
1305-3380
35-115
455-910
420-2470
15-30
225-560
9.0
y
/o
Reduction
Mean Range
81
27
95
60
+41
96
53

76-83
18-35
91-97
45-71
+17-+105
94-99
49-59

*  The Table records data from extensive laboratory and pilot plant  studies  at  five  different meat
   packing plants.

** All analyses as outlined in Standard Methods (2).

-------
                 TABLE 3.  TYPICAL CHEMICAL COSTS* FOR THE TREATMENT OF A
                           MEAT PACKING PLANT WASTEWATER AS DISCHARGED  FROM
                           A SAVEALL SYSTEM

Chemical
Sulphuric Acid (98%)
Hydrated Lime
Phosphate Coagulant
Flocculant

Mean
Concentration
(g/n»3)
275
385
200
2
Total

Unit
Cost
($/ tonne)
73.
50.
30.
3250.
Chemical Cost ($/m3)
C$/1000 U.S. gals)
Treatment
Cost
($/m3)
0.020
0.019
0.006
0.007
0.052
0.20

 *Chemical cost  in New Zealand as  at April 1976.
           TABLE  4.   TYPICAL  UTILITY  CHARGES*  FOR THE  TREATMENT  OF A
                     MEAT  PACKING PLANT WASTEWATER (4500 m3/day) AS
                     DISCHARGED  FROM  A SAVEALL SYSTEM
Utility
Labour
Oil
Steam
Electricity


Approx. Usage
per m3 of Effluent
Treated
$ 3.00/hr
$ 110/tonne
$ 9.20/1000 kg
$0.021/kWH
Total Cost ($/m3)
($/1000 U.S. gal)
Treatment
Cost
($/m3)
0.015
0.027
0.009
0.007
0.058
0.22
*Typical utility charges in New Zealand as at April  1976.
BY-PRODUCT RECOVERY

The recovery and handling of solids is an important feature of any waste
water treatment scheme as in the majority of processes 40-60% of the capital

                                     312

-------
            ACID DEMAND TO ACIDIFY UNTREATED MEAT RACKING
          PLANT EFFLUENT TO  pH 3.0 AS A FUNCTION OF C.O.D.
  \4000
  O)
I  3000
H—
«^
UJ
     2000
  (0
  O
  o  1000
  d
  s     .
Figure 2
  \ 4000
  O)
     3000
  UJ


     2000
     1000
  Q
  8
Figured
                       Plant 1 ©
                P5 ©
                       P2
                          P3
                                  P4 ©
              100     200      300      400     500
                      Sulphuric Acid Demand (mg/l)

          LIME USAGE TO NEUTRALIZE ACIDIFIED EFFLUENT
          TO pH  9.0 AS  A  FUNCTION  OF C.O.D.
                              Plant 1  A
                           P2  A
                         P3  A
                                       A P5
                                         P4 A
              100     200     300      400      500
                       Hydrated Lime Use (mg/l)
                               313

-------
 investment  is  involved.   This  aspect  is  especially significant to a process
 in which the recovered by-product is  saleable and utilized to offset treatment
 operating costs.   For these  reasons considerable emphasis in the overall
 process  development  has  been extended to evaluating a suitable method of
 solids recovery and  to the nutritional value of the product as an animal
 feed.

 Sludge Conditioning  and  Dewatering

 The basic aim  of  sludge  treatment is  to  reduce the volume and render the
 sludge inoffensive for disposal or recovery as a by-product.  Sludge
 conditioning refers  to chemical and physical methods for altering the sludge
 properties  to  permit the release of water.  In general organic sludges require
 some form of conditioning prior to dewatering to transform the characteristic
 amorphous gel-like structure into a porous mass which is more readily dewatered.

 In  this  process heat treatment is employed to break down this gel-like
 structure and  permit dewatering without  further chemical treatment.  A change
 in  particle structure results due to  the coagulation of proteins and the
 release  of a proportion  of unbound grease.

 Heat treatment is  by direct  steam injection.  To reduce the steam requirement
 the  sludge is  initially  thickened and  preheated in a heat exchanger, using
 hot  water from the dewatering stage to recover most of the sensible heat.

 The  coagulated sludge is  then partially dewatered in a horizontal bowl
 decanting centrifuge with continuous  solids discharge.  The bowl and conveyor
 speeds,  and the pond depth are chosen  so as to optimize solids recovery and
 cake moisture  content.

 The  composition of effluent  to be treated will determine the percentage of
 free fat  present in  the sludge.  When  heated a proportion of this fat may be
 rendered  and leave the centrifuge in  the liquid phase.  If sufficient
 quantities are present economic recovery may be justified before the centrate
 is recycled.

 For by-product recovery the  discharged centrifuge solids are pneumatically
 dried to  approximately 92-93% solids.   A short residence time in the pneumatic
 dryer ensures minimum thermal degradation of the product.

By way of example  the pilot  scale dewatering of a sludge recovered after
 treatment of a meat  packing  plant effluent by this process is discussed:-

Thickened sludge recovered after sedimentation was heat coagulated at
 103-105°C for approx. 1 minute before  passing directly to a 15 cm diameter
horizontal bowl decanting centrifuge.   Optimum centrifuge differential speed
and pond depth consistently produced performance data as outlined in Table 5.

The centrifuge cake  solids were particulate in form and were further dewatered
in a pneumatic dryer to achieve a final moisture content of less than 7%.
                                     314

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              TABLE 5.  CENTRIFUGE PERFORMANCE IN DEWATERING SLUDGE
                        RECOVERED AFTER CHEMICAL TREATMENT OF MEAT
                        PACKING PLANT EFFLUENT

             Parameter                               Level Recorded


Sludge Flow  (1/min)                                         20

Input Settleable Solids (%)                                  4

Centrifuge Cake Solids Content (%)                          40

Centrate Settleable Solids (%)                             0.3

Centrate Floatable Grease  (%)                              1.3

Settleable Solids Recovery (%)                              92


By-Product Use as an Animal Feed

Clearly the value of any recovered by-product as an animal feed will in
part depend on the composition of the effluent treated.

By comparison with many present meat meal feed materials the recovered
by-product is generally low in protein and high in total grease content.
For this reason the product is used as a dietary supplement for non ruminant
animals, being incorporated in the feed at apportioned levels, often ranging
between 5-15% inclusion.  For this application the by-product grease content
may be used in place of tallow, often added to feeds to improve the metabolic
efficiency.  ME/CP Qfetabolisable Energy/Crude Proteins).

Comparison of supplements from the treatment of meat packing plant effluents
with that of a typical meat and bone meal show that the ranges for crude
protein, total grease, and ash content on a dry basis are as follows:

                           „       .             Effluent      Meat and Bone
                           Component	=		
                           	c	            Supplement         Meal

                     Crude Protein (Nx6.25)      20-35%           45-55%
                     Ash                         20-35%           10-20%
                     Total Grease                20-40%            5-15%

The range reflects the variation between effluent from different meat packing
plants and the seasonal variations within a plant.  Analyses also indicate
sufficient concentrations of essential amino acids such as lysine and
tryptophan for the feeding of these materials to hogs and poultry.

In the main broiler chicken feeding trials have been used to assess the
nutritive value of the effluent by-product.  Compared to hog feeding trials
these have allowed for more extensive evaluations with the limited material
available.  It was also considered chickens in broiler feed trials would be

                                     315

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 more susceptible to diet inadequacies than many  other species.

 A recent trial by the Poultry Research Centre in New Zealand  to  test the
 feeding value of meat packing plant effluent by-product meal  when fed to
 broiler grower chickens showed that the Effluent Supplement resulted in
 comparable growth to similar inclusions of Meat  and  Bone Meal (containing
 50% crude protein).  The effluent meal used in this  trial had a  nutrient
 composition on a dry wt. basis as follows:

                        Crude Protein (Nx6.25)(%)       30.0
                        Ash (%)                 ~        29.8
                        Total Grease (%)                30.0

 The effluent meal and meat and bone meal supplements were individually
 incorporated in separate diets with levels of inclusion ranging  from 0-14%.
 The broiler grower  chicks were randomised over 74 quad boxes  with 7 males and
 7  females per box,  and placed in tiered electrically heated battery brooders.
 Evaluation of the results and an analysis of variance showed  the effluent
 by-product produced greater weight gain than the equivalent inclusion of meat
 and bone meal over  the three week growth period  and  that the  rate  of weight
 gain to food consumed was similar for both diets.  These results are shown
 in Figure 4.  The conversion of feed to  body weight  increased with increasing
 inclusion for both  diets and this is attributed  to an improved ME/CP ratio.
 No toxicity or palatability problems were encountered and in  a separate trial
 the effluent meal ash concentration (dry wt.  basis:   43.6% Ca, 15% P) was
 found  to have no  significant effect on growth for ash inclusions in the total
 diet varying from 0-8%.

 It was  concluded  the effluent by-product can perform as well  as  a meat and
 bone meal and could  be  a useful dietary  supplement in poultry rations and
 hog diets.   Results  indicate a  market value  (April 1976) of approx. $(N.Z.)
 90-100/tonne may  be  acceptable  for a meal of  this composition.

 FULL SCALE  PLANT  DESIGN

 Process performance has been consistent  through the development stages of
 laboratoty,  pilot plant  and full  scale plant  operation.  A comparison of
 laboratory  and  pilot  plant  results  for  the treatment  of meat packing plant
 effluent  as  discharged  from a  saveall  is  summarized  in Table 6 and Figure 5.
 Pilot plant  operations treated  4 m^/hr of effluent as  shown schematically
 in  Figure  1, with the by-product being recovered  for  poultry feeding trials.

 The only  large  scale  application  to  date  has  been a  plant treating 110 nrVd
 of  effluent  from  a poultry  processing operation.   Pilot scale studies on the
 treatment of meat packing plant effluent  have led to  preliminary full scale
plant design  for  a treatment plant  to process 4500 m^/d of effluent with the
recovery of  some  8 tonnes of dried by-product per day.  Typical costs
 (April  1976)  for  a plant  to  treat  this volume of effluent and produce a dry
bagged by-product are in  the range of $(N.Z.) 700,000-800,000.

In general the economic viability of such  a plant is dependent on specific
plant locality and circumstances.  However in one instance,  for a specified


                                     316

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            CONVERSION OF FOOD TO
      BODY WT. GAIN FOR EFFLUENT MEAL
           AND MEAT & BONE MEAL FOR
         P.R.C. POULTRY FEEDING TRIAL
      0.40
      0.35
  (0
  O
    CO
      0.30
    £
      0.25
      0.20
<» Meat & Bone Meal
A Effluent Meal
                    Increasing Meal Inclusion
             120   110   100   90   80
                     ME/CP Ratio
         70    60
Figure 4
                       317

-------
oo
     TABLE 6.  COMPARISON OF LABORATORY AND PILOT PLANT PERFORMANCE FOR THE CHEMICAL TREATMENT OF  A MEAT
               PACKING PLANT EFFLUENT AS DISCHARGED FROM A SAVEALL SYSTEM
Mean Daily
Composite Value
Effluent Component"1" of Untreated
Effluent to
Laboratory and
Pilot Plant
Total Solids (mg/1)
Total Organics (mg/1)
Ash (mg/1)
Suspended Solids (mg/1)
Total Grease (mg/1)
Protein (Nx6.25) (mg/1)
Chemical Oxygen Demand (mg/1)
2480
1630
850
1400
310
940
1340
Mean Daily Mean Daily
Composite Value Percentage
of Treated Reduction on
Effluent from Pilot Plant
Pilot Plant
2070
450
1620
70
20
390
260
15
72
+91
95
94
59
81
Mean Daily Mean Daily
Composite Value Percentage
of Treated Reduction In
Effluent from Laboratory
Laboratory
1980
550
1430
30
20
430
220
20
66
+68
98
94
54
84
     + Analyses as per Standard Methods (2)

-------
           COMPARATIVE  REDUCTION  IN
        TOTAL ORGANICS  OF  MEAT PACKING
     PLANT EFFLUENT ON THE PILOT PLANT
              AND IN THE LABORATORY
    2000

    1800

    1600
  g» 1400

  o 1200
  O
 O
  O 1000
 o
 75
 .o
     800
600
     400
     200
                        © Untreated Effluent
                        A Pilot Plant Results
                        • Laboratory Results
                          (mean results for
                          2 consecutive days
                          operation)
          9.00-H30   11.30-1.00   1.00-aOO   3.00-5.00
            am       Time(hr)         pm
Figure 5
                       319

-------
reduction in effluent 5-day Biochemical Oxygen Demand (BODs) of 70%,  the
capital cost was comparable with that for a biological trickling filter scheme
and considerably cheaper than for an ocean outfall.  Operating costs  for the
chemical treatment plant were higher than both of the other schemes,.however
the chemical treatment process did break even relative to the biological
process if $50-60 CN.Z., 1976) per tonne was obtained for the by-product.
Any higher values of the by-productwould indicate the chemical process to
be economically superior to the biological.

CONCLUSIONS

Laboratory and pilot plant studies on the application of the process
described to the treatment of meat packing plant wastes have shown that
effluent chemical oxygen demand may be consistently reduced by 75-80%.

The nutritive value of the recovered by-product compared favourably with
conventional meat and bone meal supplements for inclusions of up to 14% in
the diet of broiler grower chickens.

The process described may meet operating costs through the sale of by-products
and offer a significant return on capital depending on effluent composition
and plant locality:  for example in an urban area where land availability is
limited and water supply and sewage charges are high.

ACKNOWLEDGEMENTS

The author wishes to acknowledge the financial and technical support  of the
N.Z. Meat Industry, the N.Z. Poultry Research Centre, the N.Z. Development
Finance Corp.,  and in particular the efforts of Bill Wakelin and Eric Retter
of Morrison,Cooper and Partners.
                                  REFERENCES

1.  Grant, R.A., "Protein Recovery as an Effluent Treatment Process",  Effl.
    and Water Treat. Jour,, Jji, 616, (1975).

2.  Standard Methods for the Examination of Water and Wastewater,  14th Ed.
    Amer. Pub. Health Assn., New York,  1975.

3.  N.Z. Patent 153129 "Improvements in or Relating to Processes  for  the
    Purification of Waste Effluents and/or Processes for Extracting Protein
    from Waste Effluents Containing the Same".
                                     320

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                       WASTEWATER TREATMENT AND REUSE
                     IN AN INDEPENDENT RENDERING COMPANY

                                     by

                  William R. Isherwood* and Jack McVaugh**
INTRODUCTION
In June 1975, SARS (South Alabama Rendering Company) of Loxley, Alabama,
received an NPDES permit requiring effluent modification of the plant's
existing discharge into a local river.  By March 1977, SARS completed
and began operating a wastewater treatment system.  This treatment facility
adequately reduces the contaminant levels and provides a method by which
the treated effluent can be recycled through the rendering process.

Simplicity of operation and recycling are major system achievements, and
are considered to be the main topics of this thesis.

Simple operation is a key consideration to the success of a well-function-
ing plant, and allows less sophisticated, and thus less expensive, operator
qualifications to be set.  As was the case at SARS, no new personnel were
required, and actual plant operation was reduced to routine mechanical
maintenance of several new pumps and a blower.

Wastewater contaminant reduction is accomplished at SARS by biological
action in an earthen lagoon system.  This treatment system is designed
to produce an effluent of such high quality that this effluent can be
partially or totally reused as condenser cooling water.  Presently, the
entire effluent flow, 190,000 gpd, is being reused for cooling purposes,
with the remaining wastewater introduced to the treatment system being lost
through evaporation or lagoon leakage.  At the prevailing treated effluent
contaminant levels, however, the system could discharge over 70,000 gpd
without exceeding NPDES permit levels.  100% recycling has been maintained
for over nine months with complete satisfaction.  Thus, daily discharge
is zero.  Biological degradation reduces organic contaminant levels in
excess of 95%.
 *Ponder Engineering and Survey Company, Daphne, Alabama
**Envirex, Inc., Waukesha, Wisconsin
                                    321

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 The 1976 NPDES requirements were  clearly met, and thus far the future
 requirement—total waste  discharge  elimination—has also been achieved.

 Of secondary interest,  SARS has undertaken a pilot project by stocking the
 aerobic polishing  pond  (part  of the biological system) with catfish.  The
 fish are doing well and certainly contribute to the biological reduction
 of the BOD introduced into the pond.  More will be said of this later in
 the text.

 RENDERING PLANT AND OPERATION

 SARS,  Inc.,  located near  Loxley in  Baldwin County, Alabama, is an experi-
 enced,  well-established rendering company, constructed in 1954.

 SARS operates a batch rendering process to produce quality greases and
 tallow as  well as  dry "meat meal."  These products are rendered chiefly
 from slaughterhouse waste and restaurant meat scraps and grease, and some-
 times  fish scraps.   The processed greases are used for such products as
 feed,  soap,  lubricants, cosmetics,  and cement additives, while meat meal
 is  used almost exclusively as a protein source for animal feed, such as
 poultry feed and dry dog  food.

 The plant  layout includes several buildings which enclose the entire
 rendering  process,  plus an office building, personnel locker room and
 shower  head,  boiler room, and maintenance building.

 SARS rendering process  is not unusual.  Raw materials are trucked to the
 plant daily  and  rendered  into marketable products.  The plant operates
 five days  each week, with daily operation beginning in the early evening
 and  lasting  into the next morning.  Average process time is 13 hours.

 The  first  steps  of  the  rendering  process begin when the collection trucks
 arrive  in  the  afternoon.  Scraps  and grease are unloaded and weighed, and
 solid raw materials  are ground.   Both the ground solids and grease are
 then conveyed  to the cooking room.

 Cooking  is accomplished in three  large steam-heated ovens.   Each oven is
 individually  loaded  and sealed.   Cooking begins and automated stirring
 continues for  about  2-1/2 hours per load, or until the moisture content
being monitored  is  sufficiently reduced.   After cooking,  the renderings
are removed  from the ovens and strained.   Grease is  separated from solid
material and  stored, but the solids are further processed by screw expellers,
producing dry meat  meal and more  grease.   The dry meat meal is then milled
 into a coarse  powder.  Both the meat meal and grease are stored onsite in
larger tanks.

PLANT WASTE

The plant is located on the headwaters of the Fish River,  which offers
easily attainable non-potable water and a convenient waste carryoff.
SARS' rendering process  requires a 550 to 750 1pm (145 to  200 gpm) cooling
                                    322

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water supply which circulates through the barometric-leg condensers.
This cooling water is virtually free of contamination.

The main contaminating waste source is from washing of floors and equip-
ment after each day's operation.  Spillage during truck unloading and
grinding is unavoidable.  Much of this spillage can be reclaimed by dry
clean up measures, but always there is some grease, paunch manure, various
solids and small quantities of blood that can only be efficiently removed
by washing into conveniently-located floor drains.  Slight spills and ac-
cumulated deposits are washed daily from the cooking and finishing areas,
and these are also collected by the floor drains.

Figure 1 shows the original sewerage system before modification.  As shown
in Figure 1, a network of sewerage carried the wash water through two small
grease separators where grease is hand-skimmed and returned to the ren-
dering process.  After passing these small separators, the wash water com-
bined with one-pass cooling water at the head of the large, 75 m3 (20,000
gallon) grease separator.

This separator, shown in Figure 2, and its operations deserve some comment.
By daily hand-skimming, the effluent grease levels averaged 40 mg/1.
The floating material recovery was 600 - 1200 Ipd (165 - 330 gpd).

The contamination in the effluent was certainly not a grease problem.
However, relatively large quantities of suspended solids contributed to
biological oxygen demand and turbidity, and SARS was definitely in need
of some sort of abatement process to control the contaminated effluent.

Table 1 lists the NPDES limitations set for SARS.  The limitations, esta-
blished by the EPA, were based on a national average, and were particularly
evaluated for each rendering company on the basis of total pounds of raw
materials processed daily.

Upon issuance of the permit, it was immediately obvious to SARS that
their daily wastewater discharge need be reduced, or else a treatment sys-
tem be installed capable of producing effluent BOD 5 and TSS concentrations
less than 10 mg/1.  Realizing the difficulty of the latter method, and no-
ting the production levels of the SARS plant, the Alabama Water Improvement
Commission suggested that an average discharge of 400 m3/day (100,000 gpd)
should not be an unrealistic goal.  The design effluent ZOD^ goal was thus
approximately 15 mg/1.  Data presented in Table 2 indicated that the
discharge flow had to be reduced by 33-50%.  This was to be accomplished
by recycle of treated effluent for cooling purposes.
                                    323

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              P
                                         OVEN  LOADIWG  DOCK
                                                                 OVENS
                                                TVPICAU
                                                         ont.Mtst
Figure 1.  SARS rendering plant layout, showing original sewerage system.
                                   324

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               \     1
                \   1
COOL.IMG
\NFUUEMT
                                    PLAN
                                          ,.  AFF-^.
                                                                 -VV.1-.

b — 	 	
PX.UEMT


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mm


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mm


mm

I
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. • . • . . . . 4 . - - O ' • • ' - . 0' - . ' •
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Figure 2.  Final separator accomplishing 95% or better grease removal.
                                  325

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               TABLE 1.   NPDES DISCHARGE LIMITATIONS
                      Effluent  Characteristic



                         kg/day (Ibs/day)



                     Daily  Avg.                Daily  Max
 Flow—m3/Day  (MGD)



Total Suspended Solids



BOD — 5-Day



Oil and Grease



Fecal Coliform
7.43(16.38)



6.02(13.26)



3.54( 7.8 )
14.86(32.76)




12.03(26.52)




 7.08(15.6 )
                      Discharge Limitations



                      Other Units  (Specify)





                         Daily Avg.
                    Daily Max
Flow—m3/Day  (MGD)       400(0.10)*



Total Suspended Solids




BOD — 5-Day



Oil and Grease



Fecal Coliform           200/lOOml*          400/lOOml




*Alabama Water Improvement Commission Recommendation
                            326

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                     TABLE 2.  5-DAY DISCHARGE ANALYSIS
Characteristic
Analyzed                Date Samples Taken (1975)               Cooling
                                                              Water Grab
                  Composite Effluent Concentration mg/1      Sample mg/1
                8/12     8/13     8/14     8/15     8/16        8/16

Flow-m3/Day      553      595      727      667      557
  (MGD)        (0.15)   (0.16)   (0.20)    (0.18)    (0.15)
Total
Suspended
Solids
BOD —
5 -Day
Oil and
Grease
Fecal
Coliform
(1000's)
45 143 56 97 91
56 263 117 225 88
12 48 16 45 34
430 930 2,400 4,600 2,400
9
2
1
1.5
WASTE TREATMENT

After evaluating the effluent, a table of flows and concentrations was
developed for treatment process design purposes (Table 3).

The maximum total daily flow was set at 795 m3/day (0.21 MGD) by taking
the maximum flow recorded and adding about 10%.  Then, by measuring the
cooling flow alone, both the cooling water and the wash water flows were
determined.

It should be pointed out at this time that BOD and TSS were taken as the
main design parameters.  This is because of the nature of SARS's waste.
Being organic and readily biologically degradable, it was felt that an
aerated lagoon would efficiently reduce BOD, followed by a polishing pond
to provide further BOD reduction and a place for solids to settle out.

Suspended solids in the wash water are mostly organic and make up a large
part of the BOD.  The organic or volatile solids are aerobically converted
to non-degradable residue in the aerated lagoon.
                                     327

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               TABLE 3.   DESIGN  FLOWS  AND CONCENTRATIONS



       Influent  Characteristic                      Quantity

       Flow-m3/Day (MGD)

          A.   Total                                   795  (.21)

          B.   Cooling Water                          720  (.19)

          C.   Wash Water                               75  (.02)

       Total Suspended Solids

          A.   Cooling Water                                < 10


         B.   Wash Water                          1225

       BOD — 5-Day mg/1

         A.   Cooling Water                       <£  10

         B.   Wash Water                          2250

       Oil and Grease

         A.   Cooling Water                       <  10

         B.   Wash Water                           800
 As shown in Figure  3, the original  primary treated  effluent was the combi-
 nation of cooling water and wash water flowing from the final separator.
 As was mentioned earlier, the total discharge had to be reduced.  The deci-
 sion was made to recirculate, as cooling water, some or all of the poten-
 tial discharge after treating to remove organic contamination.

 The Implemented Plan

 Reduction of organics was accomplished by isolating the wash water from
 the cooling water and treating both individually.   Since the wash water
 has such a high BOD concentration (2250 mg/1),  it is treated in two bio-
 logical stages.  The cooling water, on the other hand, is normally very
 low in BOD and TSS, and needs only  to be cooled somewhat to be good for
 recirculation.  The cooling water is, however,  potentially contaminated
 if the ovens are overloaded, causing a boilover into the cooling system
which must be caught and treated.

                                  328

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COOLING
 wArea
 IMTAKE
                       SMA<_i.
                     SEPARATOR
                                   J	L
                             r--UJLLl
                             I
FlWAU
SEPAttATOa
                   FISM   RIVER.
           A
          Figure 3.  SARS1 original  flow pattern.
                    Cooling water and wash water combined.
                          329

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 Figure 4 shows the implemented plan.   The wash water was segregated from
 the cooling water just before entering the original final separator.  A
 new separator was constructed to remove grease from the segregated wash
 water flow, and is also hand skimmed.   From the  separator, the wash water
 is pumped to an earthen aeration basin.

 The cooling water was  left  to pass  through the original evaporator which
 serves as a trap for grease if oven overloading  occurs.  After passing
 the separator, the cooling  water is pumped to the polishing pond where
 it combines with the aeration basin effluent to  make up the polishing basin
 effluent.

 The polishing pond effluent flows to a 5-foot diameter, 10-foot deep sump,
 where pumps force recirculation as  coolant.  If  the return is ever too
 great for recycling,  it will automatically overflow into a chlorination
 basin for disinfection and  then will be  allowed  to discharge into the
 Fish River.

 Aeration Basin

 The aeration basin was required to  provide the following:

 1.   A minimum of 90% BOD removal which is  necessary to minimize the size
     of the polishing pond and to assure  adequate removal, satisfying the
     NPDES limitations.

 2.   Sufficient volume  to equalize the  normally sporadic influent.  Though
     the  daily wash water flow is only  75 nr*  (20,000 gallons) per day,
     this  flow is realized in only 10 hours.  Also, pumping the wash water
     into  the aeration  basin causes  severe  flow variation during this period.

 3.   Simple operation,  which is  a primary consideration for a successful
     treatment system of  the small scale  required by SARS.

 4.   Ease  of  construction as  an  earthen basin, sealed with heavy clay
     material.

 Considering  these requirements,  a basin with 20  days'  retention was consi-
 dered  optimum.   Equalization requirements were easily met with such a large
 retention.

 Ease of construction,  along with low capital cost, determined selection
 of  the aeration device,  a diffused  aeration header consisting of fiberglass
 pipes  and fittings  connected by  mechanical couplings.   The header took
 approximately  12 man-hours  to assemble.

 Simple operation  is inherent  to  an  aerated lagoon.  Operation of the
 aerated basin at  SARS  is confined strictly to routine maintenance of the
blowers used  in  the diffused aeration  system.  A non-clogging, coarse-
bubble diffuser was selected for  aeration, eliminating the need to dewater
 the  lagoon for  periodic  cleaning  of diffusers.   The lagoon dimensions
                                    330

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    POLISHING

      POMD
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t±
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      A
                                    JST
                                    CONO.
                                    •~^
                           new
                         SepARATor*.
                   i
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      1-
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  i .  i
                      ^y
                                    XN
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                                         Vh

                                         MP
                                    .   .
                                           -
                                             ™i
                         d
SEPAIIATOR.
        STANDBV
                   I	^?TQ.EATED
                             I EFFLUENT
                       RIVER.
                                          EXIST1KJG
     Figure 4.  The implemented treatment scheme providing
              segregation of wash flows and cooling water.
                         331

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 are 12 m (40 feet)  by 30 m (100 feet)  at the  floor, and 3.7 m  (12 feet)
 deep with 3:1 side  slopes.

 BOD removal, mixing and air input  requirements were calculated using
 theoretical assumptions in lieu of pilot tests.  The design predictions
 were as follows:

 1.   BOD removal = 90 - 95%.

 2.   Horsepower required for complete mixing = 11.25.
                            o
 3.   Air requirements = 17 m /min.   (600  cfm).

 Since the plant has been in operation, it is  realized that the BOD removal
 and air requirements have been satisfied.  Mixing requirements, on the other
 hand, were initially greatly underestimated,  but the aeration basin does
 function adequately.   Initially intended to operate as a completely mixed
 aeration basin, the realized facilities  operate as a facultative basin
 with both aerobic and anaerobic BOD decomposition.

 Polishing Pond

 Because SARS recycles the effluent  from  the polishing pond as cooling water,
 the retention time  in days  is  strictly the pond volume—10,000 m^ (2.6 MG)
 maximum,  divided  by the daily  plant discharge.  With no evaporation or
 leakage,  the minimum daily  discharge is  equal to the daily wash water flow
 plus  condensate.  If  daily  discharge is  75 m3 (20,000 gallons), the reten-
 tion in the  polishing pond  equals  130 days.

 It  is anticipated that  long retention will allow a very stable ecological
 balance in the  polishing  pond.  This balance will assure good waste removal
 characteristics.  Should  such  a long retention period prove unsatisfactory,
 however,  the daily  discharge can be increased to a maximum of 380 m3
 (0.1  MG),  allowing  a  retention period of only 26 days.   The retention can
 also  be adjusted  by changing the water level in the pond between 0.6 m
 (2  feet)  and 2  m  (6 feet) in 0.3 (1 foot) increments.

 ACTUAL  PERFORMANCE

 In mid-March  1977,  construction was sufficiently complete to begin filling
 the basins.   By June, the first effluent was realized and as soon as pos-
 sible  thereafter  an analysis of the polishing pond effluent was made.
 The results,  shown  in Table 4, were somewhat disappointing, but the system
was very  young.   Suspended solids were fairly high but  only due to initial
disturbance  of  the  clay sealer used in the basins.
                                    332

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                 TABLE 4.  RANDOM DISCHARGE ANALYSIS
Effluent Characteristic
Total Suspended
Solids mg/1

BOD  — 5-Day

Oil  and Grease

Fecal Coliforra
100  ml

PH
Date:   6/9/77


         113

          35

           1


    **4,000

           7
 *Removal


  90.8%

  98.4%

  99.9%
7/27/77   *Removal


   49       96%

   27     98.8%

  1.2     99.9%


    2     Excellent
Excellent
*Removal based on design concentrations shown in Table 3,  i.e.,
TSS  -  1225 mg/1, BOD - 2250 mg/1, Oil and Grease -  800 mg/1.

**Coliform is relatively high because chlorination  equipment  had
not  been completed by this sampling  date.
  By mid-July, the system seemed better stabilized and another polishing
  pond discharge analysis was made.  The results,  also shown in Table 4,
  were more encouraging.

  One effluent characteristic not included in Table 4 is daily discharge.
  And to  this date, no  discharge from the system has been required.  Several
  times for testing and flushing purposes small discharges have been allowed;
  otherwise, 100% recycling has been maintained.  This is due to a reduction
  in wash water utilization, normal  evaporation, and leakage.

  Because the polishing pond provided good results, SARS decided to stock
  it with native freshwater catfish.  A thousand fingerling fry were intro-
  duced to the pond and seem to be doing well.  The idea to create a well-
  balanced ecological equilibrium seemed incomplete without catfish, and surely
  they offer some assistance to the  waste removal.

  With no discharge, daily analysis  was not required, and until mid-August,
  no data was recorded.  Envirex, Inc., the manufacturer of the aeration
  equipment, offered to run an analysis consisting of three separate samplings
                                   333

-------
 to evaluate the treatment efficiency.   Each  analysis was to measure the
 total and soluble BOD and total suspended solids of the untreated wash water,
 in the aeration basins,  and in the polishing pond  effluent.  Grab samples
 were taken for each day's test, but the time the samples were taken was
 changed to reflect various periods of  the rendering schedule.  The results
 were averaged and appear to be a fair  indication of the plant's behavior,
 as shown in Table 5.
                TABLE 5.   AVERAGE TREATMENT EFFICIENCY ANALYSIS
                                Aeration           Stabilization
 Characteristic     Influent     Basin*      Removal    Basin*    Removal

 BOD —  5-day
 mg/1                 2260         305         86%        18        94%

 Total Suspended
 Solids  mg/1           3672        2411         34%        39        98%

 Soluble BOD —
 5-Day mg/1            850         90

                                Overall Removal

 BOD —  5-Day mg/1                    99.2%

 Total Suspended Solids mg/1            99%

 Soluble BOD — 5-Day mg/1
*Effluent
To thoroughly understand SARS' or any treatment plant, samplings should
be continued until trends are documented for the seasonal changes.  Under-
standably, however, SARS is reluctant to conduct such analyses if not re-
quired by the state regulatory agency.  Recycling allows SARS zero dis-
charge and their adopted operation philosophy is as long as the system ap-
pears well, it is considered to be functioning properly.

Another point of interest is that during September of 1977 when the records
of the efficiency samples were taken, it was noticed that an algae bloom
was developing.  Algae was, of course, prolific in the polishing pond
and was anticipated.  Suspended solids in the pond are mostly algae and
these plants are considered advantageous in a well-balanced aquatic eco-
system.
                                    334

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When the bloom was first observed, it was feared that treatment efficiency
might be falling off as a result, but one of the best test results was
received during this period.  Suspended solids were still acceptably low.

The accelerated algae growth was short-lived.   Within three weeks of the
initial sighting, the bloom dispersed.

ECONOMICS

The total cost incurred to implement this concept ran approximately
$300,000.  Continued costs to SARS for the use of the treatment facilities
are the operation and maintenance for two 10-horsepower and one 3-horse-
power pumping stations, and two 15-horsepower aeration blowers.  Of course
chlorine and maintenance of its associated equipment are a potential cost
if ever utilized, in the event that discharge of treated effluent to the
Fish River becomes necessary.
                                    335

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              THE  IMPACT  OF  THE  CLEAN  WATER ACT  OF  1977 ON THE
                          FOOD PROCESSING  INDUSTRY
                                   by
                             Carl  Schafer*
 A  major  legislative  milestone  in  1972 was  the passage of the omnibus Federal
 Water  Pollution  Control  Act  Amendments,  P.  L. 92-500.  Among its many pro-
 visions  was  one  for  midcourse  corrections.  After three years of study,
 hearings,  and  debate,  these  midcourse corrections were signed into law on
 December 27  as the Clean  Water Act  of 1977, P.  L. 95-217.

 The  Philosophy behind  the 1972 law  was to  "restore and maintain the chemical,
 physical and biological  integrity of the native waters."  The Law called for
 fishable and swimable  waters by 1983 and a  goal of zero discharge of pollu-
 tants  into major waterways by  1985.

 Instead  of using water quality standards to control pollution, an approach
 that produced  uneven results,  the 1972 law  shifted to a permit system.
 Dischargers  had  to limit  the amount of pollutants according to Federal
 guidelines or  "effluent  limitations", that were based on the level of cleanup
 possible with  certain  technologies.

 By July  1, 1977, industry was  required to meet  standards set using "best
 practicable  technology (BPT)."  By  1983, as new and more effective equipment
 was developed, the effluent  limitations  were to reflect the cleanup possible
 with the "best available  technology economically available (BAT)."

 The Clean  Water  Act  of 1977  generally preserves the substantive aspects of
 The Federal  Water Pollution Control Act  (P.L. 92-500).  Changes are in the
 nature of  "fine  tuning" in the  area of statutory thrust.  The new Act is more
 realistic  and  directs  priorities  towards the control of toxic pollutants.

 The transition from  rather broadly worded provisions in P. L. 92-500 regard-
 ing industrial point source controls, including effluent limitations, to a
 more realistic structure  of pollutional  controls was effected by definition
 of three characteristic groups  of pollutants—each with its own regulatory
 and administrative requirements.  Thus we now have three types of technology-
 based effluent control groups;  toxic compounds, conventional pollutants and
 non-conventional  pollutants.
*Division Director, U. S. Environmental Protection Agency, Industrial and
Extractive Processes Division (RD-681) Washington, D. C.  20460
                                    336

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Toxic compounds are basically the 65 classes of toxic compounds incorporated
into the new statute in Section 307 from a consent decree agreement entered
into by the Environmental Protection Agency (EPA) and the Natural Resources
Defense Council (NRDC).  Control of these pollutants will be through effluent
limitations established with "best available technology" (BAT) requirements.
These effluent limitations will be promulgated by EPA no later than July 1,
1980 and they must be achieved by no later than July 1, 1984 by those classes
and categories of industrial point sources identified by EPA as being subject
to this requirement.  There will be no economic or environmental  variances
granted from BAT effluent limitations and effluent standards for "toxic"
pollutants.

For the present, the types of industry concerned with toxic pollutants are
the 21  "heavy" industry categories covered by the consent agreement.  Food
processing industry categories are not now specifically affected by this
program.  However, sampling of food processing plant effluents for possible
toxic components is an important part of EPA's research program in the area
of industrial wastewater treatment.

Pollutants of essential interest to the food processing industry are those
that fall under the new category of conventional pollutants.  The pollutants
include biochemical oxygen demand (BOD), suspended solids (TSS), pH, fecal
coliform and potentially others in the "traditional" sense as may be defined
by the Aministrator pursuant to Section 309.

Technology-based limitations are still required; however, a new level of
technology is to be defined for establishing limits for these pollutants;
namely, "best conventional pollutant control technology" or BCT.  This
technology requirement has been defined by the Congress to include the
technical factors originally used to define BPT and BAT requirement, but
with a new "cost test."

The cost test is comprised of two essentially interrelated factors:
(1) reasonableness of the relation between the cost and the effluent reduc-
tion benefits; and (2) comparison of the industry category or subcategory
cost and associated pollutant reduction for publicly owned treatment works.

The cost test is to be applied to any forthcoming future regulations
establishing limitations for conventional pollutants.  Thus, for example,
(with resources permitting) regulations not previously finalized in indus-
tries such as poultry processing, miscellaneous food specialities, beverages,
edible oils, and others would be finalized as BCT regulations.

In addition, the statute requires the Agency to review the "old" BAT
limitations for conventional pollutants for the industries not covered by
the toxic limitations program.  These industries (so called "secondary
industries" as a term to differentiate them from the heavy "primary
industries") include all of the food processing categories and subcategories
for which BAT limitations were promulgated and in effect at the time of
passage of the Clean Water Act.  Specific food industries covered in this
review are all subcategories of the fruits and vegetables, meat products,
seafoods, dairy, sugar, and grain mill processing industries.
                                     337

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 A  brief  description  of  the  review  process may be helpful.  The secondary
 industry review  involves  some  14 industry categories and over 200 subcate-
 gories.   All  data  as to costs,  level of  pollutant  reduction and specific
 limitations  requirements  were  assembled  and  reviewed.   Initial review
 focused  on defining  the population of  subcategories for which the "cost
 test"  must be performed.  Thus, for example, about half the subcategories
 for which BPT was  zero  discharge or where BPT and  BAT  requirements were
 equal  were screened  out of  the  review.   Coincident with this screening
 process, costs and performance  relating  to POTW control of conventional
 pollutants were  compiled.   Cost comparisons  were made  on an incremental
 basis, i.e.  the  cost and  pollutant reduction going from BPT to BAT for
 industry vs.  the POTW counterpart  going  from average (or good) secondary
 treatment to best  secondary treatment.

 Section  301  requires classes and categories  of  industrial point sources
 discharging  "conventional"  pollutants  to achieve by not later than July 1,
 1984,  effluent limitations  requiring application of BCT to be defined by
 EPA.   Again, there will be  no  economic or environmental variances granted
 from BCT effluent  limitations  for  conventional  pollutants.

 The third group  of pollutants  are  those  which are  not  specifically listed
 as either "toxic"  or "conventional" and  are  therefore  termed "non-
 conventional."  These pollutants are to  be regulated by BAT level technology
 standards.   Section  301 (b)  requires category and  classes of industrial
 point  sources which  discharge  other than toxic  or  conventional pollutants to
 achieve  BAT  by July  1,  1984 or within  three years  after promulgation by EPA,
 but in no case later than July  1,  1987.

 In contrast  to requirements  for conventional and toxic pollutants, owners or
 operators are entitled  to apply for a  waiver from  the  BAT requirements for
 "non-conventional" by one or both  of two mechanisms:   (1) Section 301 (c) which
 allows waivers based upon economic circumstances (affordability) of the
 permittee while  at least  BPT is achieved; and (2)  Section 301 (g) which
 allows for waivers based  upon environmental  considerations among which are
 that (a) water quality  standards are being achieved, (b) if a waiver is
 granted,  no  other  point source will have to  upgrade treatment to compensate
 for the  waived requirements, and (c) at  least BPT  is being met.  In addi-
 tion, it  should  be pointed  out that the  compliance date for toxic pollutants
 can be extended  to July 1,  1987 if the facility is going to employ an
 innovative production process or new treatment technology which will result
 in a greater  effluent reduction than required or significantly lower costs
 for reaching  the required reduction.

Although the  provisions of  the new law relative to effluent limitations are
of major interest  to  the food processing industry, there are other features
of the Act which are  also of interest to this industry.  In regard to
industrial cost recovery  (ICR)  payments, EPA is required to study the
efficiency of, and the need for, such payments.   This  study is to include,
but is  not limited to, an  analysis  of the impact of ICR payments on rural
communities  and on industries in economically distressed areas or areas of
high unemployment.   The study is to be completed and submitted to the
                                     338

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Congress within twelve (12) months after December 27, 1977.  In addition,
Section 204 (b) allows POTW managers to reduce the amount of ICR payments
where an industrial user reduces its total flow of sewage or unnecessary
water consumption.  This section also exempts from ICR requirements those
industries discharging 25,000 gallons or less per day into municipal
treatment plants as long as the effluent does not contain toxic chemicals
or other materials that would contaminate or reduce the utility of the
resulting sludge.

The Act specifically defines irrigation return flows and their cumulative
effects as non-point sources.  Further, the Department of Agriculture is
authorized to establish and administer a cost sharing program to assist
farm owners and operators to install and maintain measures necessary for
control of non-point sources of water pollution.  Grants may not exceed 50
percent of approved non-point source pollutant abatement measures.

Industrial direct discharge plants unable to meet the July 1, 1977 date for
compliance with best practicable technology (BPT) because of contemplated
future discharge into a POTW may submit a request to appropriate NPDES
permit issuing authorities for extensions of time (but no later than July 1,
1983).  Time extensions up to April 1, 1979 may be granted by NPDES permit-
issuing officials to industrial plants not contemplating discharge into
POTW's if it is found that the discharger has acted in "good faith" and if
facilities necessary to comply with the BPT requirements are under construc-
tion.

EPA is required (by the Act) to conduct a study of the effect of the disposal
of seafood processing wastewaters into marine waters.  The study is to
examine the geographical, hydrological and biological characteristics of
marine waste-waters into which such wastes are discharged.  In addition, the
study is to examine technology which may be used to facilitate the use of
nutrients in seafood processing waste waters or which may be used to reduce
the discharge of such wastes.  The result of the study is to be submitted
to the Congress no later than January 1, 1979.

Although it was not incorporated into the final version of the Act, the
legislative conference report directed the Administrator to conduct a study
to be completed by January 1979 to ascertain if there is merit to argument
that some Virgin Islands and Purerto Rico rum distillers might safely
dispose of certain natural wastes untreated into the marine environment.  In
this study the Administrator should specifically examine geographical,
hydrological and biological characteristics of marine waters receiving such
wastes to determine if the discharge can be environmentally acceptable either
for the purpose of aquaculture or some other purpose.  In addition, the
study should examine technologies which might be used in these industries to
facilitate the utilization of the valuable nutrients in these wastes or the
reduction in the discharge to the marine environment.

I have tried to discuss the provisions of the new law which will have the
most impact on the food processing industry.  In general, the new law
stresses innovative, alternate wastewater treatment technology (recycling
                                    339

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and reuse of wastewater including sludge, land treatment, and methods to
decrease wastewater volume) with an emphasis on the importance of control-
ling toxic pollutants.  I would like to take this opportunity to encourage
each of you to carefully review the new act and EPA's proposals for imple-
mentation and to provide us with comments on those aspects you feel are
appropriate.
                                    340

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                 THE APPLICATION OF DEEP SHAFT TECHNOLOGY
              TO THE TREATMENT OF FOOD PROCESSING WASTEWATER

                                    by

               D.S. Sandford, P.Eng.* and T. Gallo, P.Eng.**
 INTRODUCTION

 The Deep Shaft Effluent Treatment System is a high rate activated sludge pro-
 cess.  It was developed by Imperial Chemical Industries in Great Britain in
 co-operation with various ICI subsidiaries around the world.  The responsibil-
 ity for the development of the technology in North America rests with Canadian
 Industries Limited,  (CIL), through their wholly owned subsidiary, Eco Research
 Ltd. of Montreal, Quebec, Canada.  Marketing of the technology in the United
 States is the responsibility of CIL-Chemicals, Inc. of Detroit, Michigan, also
 a subsidiary of CIL.

 The North American version of the technolgoy features the Deep Shaft concept
 for aeration but utilizes flotation as an effective method of solids separa-
 tion rather than conventional gravity sedimentation.

 Initial work involving flotation as a method of achieving reliable suspended
 solids separation was demonstrated at Emlichheim, W.Germany where a Deep
 Shaft roughing treatment plant was built to treat potato processing wastewater
 for the KSH Company(1).

 The Deep Shaft Effluent Treatment System is proving to be highly effective for
 the treatment of high strength readily biodegradable wastewaters which are
 normally found in the food processing industry.

 The Deep Shaft Effluent Treatment System has also been successfully applied
 to the secondary treatment of municipal and industrial domestic blends of
wastewater(2)(3)(4).  North America's first full-scale autonomous Deep Shaft
plant is currently under construction at the Town of Virden, Manitoba and is
designed to treat the entire town's wastewater (ie. 5,000 population equiva-
 lent) .

Several technical articles will be presented in the next twelve months regard-
ing the operation of a Canadian Deep Shaft demonstration plant that has suc-
cessfully treated brewery wastewater(5)(6).

Anheuser-Busch, Inc. of St. Louis, Missouri will be one of the first American
corporations to pilot Deep Shaft technology.  The Deep Shaft pilot plant at
Anheuser-Busch in Williamsburg, Virginia will start-up in early April 1978.
 *Eco Research Ltd.; Calgary, Alberta, Canada
**Eco Research Ltd.; Toronto, Ontario, Canada
                                     341

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 Interest in the technology is growing in all sectors  of  the  food processing
 industry,  as industrial surcharges and land values  increase.

 This paper should provide an overview of the operation of  a  Deep Shaft demon-
 stration plant which has treated brewery wastewater at Molson Breweries of
 Canada Limited at Barrie,  Ontario, Canada and a pilot plant  operating on
 dairy waste for the Co-operative Agricole de Granby,  Notre Dame du Bon Conseil,
 Quebe c,  Canada.

 The information collected in the course of this work  enables us to develop,
 with a high degree of confidence, cost estimates  and  designs for full-scale
 brewery and dairy applications.

 PROCESS  DESCRIPTION

 Coarse screening and grit removal are normally the  only  forms of pretreatment
 which proceed the Deep Shaft Effluent Treatment System.  Primary clarification
 is  not required in advance of the Deep Shaft bioreactor.   Aeration takes place
 in  a totally cased and grouted shaft  100 - 250 metres (300 - 800 feet) in
 depth, which is divided into a downcomer and riser  section by a partition or
 a concentric tube arrangement.   The wastewater is circulated around the shaft
 using the  airlift principle.   As the  circulating  mixed liquor in the shaft
 reaches  the surface,  the entrained air bubbles are  allowed to escape and a
 portion  of the flow is fed by gravity to a flotation  cell  for solids separa-
 tion while the remainder of the  flow  is recycled  back to the shaft.

 The  advantages of the Deep Shaft bioreactor arise from the geometric configur-
 ation of the shaft.

 As the injected air  in the downcomer  is entrained in  the downward flowing
 wastewater,  it experiences an increase in hydrostatic head resulting in dra-
 matically  improved oxygen  transfer due to increased oxygen solubility in
 the  lower  regions of  the shaft.   This  results in  a  more complete and effec-
 tive  oxygen penetration into the floe.   Thus,  oxygen  utilization by the biota
 becomes  the limiting  process  rather than the transfer of oxygen to the biota
 as in conventional systems.

 The healthy physiological  environment  created in  the  bioreactor for the biota
 appears  to  result in  a considerably higher kinetic  rate than in conventional
 activated  sludge  systems.   Therefore,  Deep Shaft  bioreactors tend to be
 extremely  small in volume  when compared to conventional systems.

The air  that is added to the  bioreactor to supply oxygen to  the biota also
provides the driving  force for hydraulic circulation  and suspended solids
 separation  in  a flotation  cell following the Deep Shaft bioreactor.  These
are the major  reasons  for  the exceptional  power economy attained by the
system.

The increased dissolved oxygen in  the  bioreactor, coupled  with high turbu-
lence, results in  a highly aerobic, well  oxygenated biomass and prevents the
development of filamentous  organisms.   The turbulence in the bioreactor tends
to comminute filaments, resulting  in short,  easily  separable fragments.

                                     342

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The plug-flow nature of the shaft, preceded by complete mix circulation at
the top of the shaft, is effective in diluting influent BOD5 and reducing pH
shock loads.

The metabolic cycle of the biomass in the Deep Shaft bioreactor, the result
of plug-flow mode of operation, may be responsible for the lower sludge pro-
duction experienced in Deep Shaft plants when compared to other high rate
activated sludge systems.

The subsurface placement of the shaft and the large recirculation volume en-
sures a near constant temperature in the shaft all year round which is of
particular importance in extreme climates.

Since the Deep Shaft Effluent Treatment System is highly aerobic, there are
no putrescent odors.  This, coupled with the small surface area requirements
of the technology, allow plants to be totally enclosed resulting in a very
favorable working environment.

The flotation mode of suspended solids separation is significant since:

(a)  A reduction is possible in the size of suspended solids separation
     equipment because the rise rates in a Deep Shaft flotation cell are
     3-4 times that of conventional clarifier settling rates.

(b)  The efficient use of readily available dissolved gas allows a high
     concentration of mixed liquor suspended solids to be separated
     efficiently.

(c)  Floating sludge is thickened to 4-8% in the flotation cell elimin-
     ating the need for sludge thickening equipment and the associated
     energy costs.

Figure 1 and 2 illustrate the process schematics used to demonstrate the via-
bility of the Deep Shaft Process to treat dairy and brewery wastewater respec-
tively.

DAIRY WASTEWATER TREATMENT

Wastewater from the cheese and powdered milk producing plant of the Co-oper-
ative Agricole de Granby at Notre Dame du Bon Conseil, Quebec, Canada has
been successfully treated using the Deep Shaft Effluent Treatment System.
The pilot plant consisted of an 20 cm x 157 m (8" I.D. x 500') deep shaft
containing a 6.76 cm (2.66") I.D. U-tube bioreactor.  Solids separation was
accomplished in a separate cell following the bioreactor.

The results of the pilot plant study provide the design criteria enabling Eco
to design full-scale Deep Shaft dairy wastewater plants.  Figure 1 shows the
schematic of the plant.

As the full-scale plant is expected to operate at higher than ambient temper-
ature, provision was made for controlled heating of a water jacket.
                                     343

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DEEP SHAFT
                                        <3-
                                     A
                                  POLYMER

                                   MIX
                                                   V
   V
    i

	J
               {
                                                                T
                                                                 i
                                                          \7
                                                       SINK RECYCLE
                                                  SOLIDS SEPARATION
                                    FIGURE 1,  BON CONSEIL DEEP SHAFT

                                               PILOT PLANT SCHEMATIC,
                                                                             INFLUENT
                                                                             UREA
                            •EFFLUENT

-------
                     FIGURE 2,  MOLSONS DEEP SHAFT DEMONSTRATION  PLANT
                                BARRIE, ONTARIO, CANADA.
  BREWERY
              .—' 300 GPM
CO
-P»
U1
EFFLUENT
^/ 50
COo 	
>
;
GPM
50,000
EQUALI
TANK *
+> ADJUS1
: 	 ^
i

^
GAL
ZING
, PH
"ME NT
                           4,000,000 GAL
AERATION
  CELLS
                                                       CLARIFIERS
TREATED
                                                                       EFFLUENT
             ->SEWER
                                  SLUDGE RETURN
                                            OPTIONAL RETURN  LINE
                                                       TREATED
                                                     -EFFLUENT
                                                                   FLOTATION

                                                                      TANK
                     260 ft'
                                 FLOW

                                CONTROL
                          800 ft

-------
 Air is added to the downcomer side of the shaft as a source of biological
 oxygen.  Pilot scale shafts require additional air to maintain circulation
 and this can be provided by adding airlift on the riser side of the shaft  or
 by the provision of mechanical pumping.

 The head box provides the free surface area necessary to allow disengagement
 of gas bubbles.  Dissolved gases in the riser side of the shaft slowly come
 out of solution forming microscopic bubbles which attach to the floes,  creat-
 ing the driving force for suspended solids separation by flotation.

 The solids separation tank is cylindrical with a conical bottom.   Provision
 is made to collect both floating and settled solids.  Collected bottom and
 top solids are returned to the shaft.

 The shaft was drilled in February and March of 1977 and the plant was  ready
 for commissioning in early May 1977.  The objective was to define the  Deep
 Shaft operating and design parameters for dairy treatment.

 The results on a one week intensely monitored period,  as presented below,
 were undertaken from October 25 to November 1,  1977 at which time the  plant
 was operated continuously with 24 hour per day supervision.   Various streams
 were analyzed including influent,  mixed  liquor,  effluent and wasted sludge at
 1  or 2  hour intervals.
 The
operating conditions for the test period are outlined in Table 1.


           TABLE 1.  BON CONSEIL DEEP SHAFT PILOT PLANT
                     OPERATING PARAMETERS
                     SEVEN DAY INTENSIVE TEST PERIOD
Parameter                               Metric                   USA

Feed Rate                          8.74 ±  .08 m3/hr.       0.5 ± 0.05 USGPM

Bottom Recycle Rate                  8.74 m3/hour              0.5  USGPM

Air Injection Rate              8.5 N m3/hr @ 690 KN/m2    5 SCFM @ 100 psig

Mixed Liquor Temperature                 32 C                    90°F

Mixed Liquor Suspended Solids         5,000 mg/1              5,000 mg/1
In late November 1977 a series of tests were conducted on a feed prepared by
dissolving dry whey powder in tap water and feeding this to the shaft, allow-
ing drastic fluctuations in the loading resulting in variable sludge ages and
changing physiological conditions.  During the last period of this two week
experiment, alum was added to determine its effects on overriding fluctuating
load and to improve effluent clarity.  Drastic improvements in the floating

                                     346

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 behavior of  the  sludge  occurred, providing alum was added to the shaft at a
 concentration of 1 mg of  trivalent aluminum/gram of MLSS.  The suspended
 solids  concentration in the effluent was reduced to a level averaging 49 mg/1
 in 24 hour composites during  the final six days of the tests.  Since these
 values  were  obtained on dissolved whey powder, normal dairy wastewater should
 result  in better sludge characteristics and solids separation.

 Sludge  production has been measured to be 0.5 kg of sludgeAg of BOD treated.
 Consideration has been  given  to suspended solids escaping in the effluent.

 Healthy microflora included bacteria of diverse morphology  (ie. cocci, bacil-
 li,  long thin rods and  occasionally fragments of filaments).  Protozoa present
 in the  healthy sludge include colonies of Opercularia and active Vorticella.
 No visible difference in  the diversity of the microflora was observed whether
 dairy waste  or whey was being treated.  The floes produced by artificial whey
 influent looked  more open and fragile than floes produced by dairy feed.

 Filamentous  organisms often plague conventional dairy waste treatment plants,
 however filamentous bacteria were only observed on rare occasions when the
 shaft did not receive adequate oxygen for reasons of foaming or organic over-
 loading.  No filamentous  bacteria occurred after excess oxygen was provided
 to take care of  all load  conditions.

 Provision was made for  continuous monitoring and control of pH of the mixed
 liquor.   It  became evident that the mixed liquor was naturally buffered be-
 tween a pH of 6.9 and 7.6.  No additional acid or alkali was required to
 keep the pH  in this range, although the client's record of raw dairy effluent
 pH showed a  dramatic fluctuation between 2 and 12.

 Discussion of Process Behavior During Seven Day Intensive Study

 Results of Seven Day Intensive Study

 Table 2 outlines the results of the seven day intensive study conducted be-
 tween October 25 to November 1, 1977.

 The results  of the seven  day intensive study indicate that an effluent of
 less than 150  mg/1 suspended solids can be attained without the use of coag-
 ulant aids.

 Throughout the seven day  intensive study, the load fluctuated sharply over a
 twenty-fold  increase in conventional F/M (ie. 0.18 - 3.2 days  ) without up-
 setting  the  substrate removal efficiency or solids separation efficiency of
 the system.  A sudden change in waste characteristics (ie. whole dairy waste
 to whey) may  require several hours of biomass acclimatization, however
 equalization  should reduce this impact.

All components in the influent appeared to be treated, in fact butter fat
 actually  aids  flotation while milk proteins cause foaming in the head tank
which can be  easily controlled with a mechanical foam breaker.
                                     347

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                 TABLE 2.   BON CONSEIL DEEP SHAFT PILOT PLANT
                           SEVEN DAY INTENSIVE STUDY PERIOD
                           PERFORMANCE
Parameter

Total BOD5
Total SS
FOG
Influent
(mg/1)
1597 (S)
498
388
Effluent
(mg/1)
125(b'c)
138
76
Removal Efficiency
(%)
98.3
72.3
80.4
        Note;   (a)   BOD5/COD ratio =0.7

               (b)   Filtered BOD5 =25  mg/1

               (c)   Filtered COD = 181  mg/1
 Changes  in the  nature  of  the waste  (ie. milk to whey) during the test period
 required several hours of acclimatization,  however  some relief from large and
 rapid variations in waste characteristics for  full-scale plants can be buffer-
 ed with  an acceptable  degree of  equalization.

 Full-Scale Deep Shaft  Dairy Plant Cost Estimate

 Table 3  describes the  influent of a 64 m3/hr.  (0.4  mgdUSA) full-scale Deep
 Shaft plant to  treat high strength dairy wastewater to 50 mg/1 6005 and 50 mg/1
 TSS specifications.
                TABLE 3.  DEEP SHAFT DAIRY PLANT COST EXAMPLE
                          WASTE CHARACTERISTICS AND TREATMENT
           Equalized Daily Flow

           Total BOD5

           Effluent TSS and BOD

           Population Equivalent
64 m3/hr. (0.4 mgd USA)

2400 mg/1 ± 30% fluctuation

50 mg/1

38,000 people
Table 4 describes the design parameters and capital cost for the full-scale
dairy Deep Shaft plant.  The Deep Shaft portion of the plant offers excellent
space economy.  It is estimated that a 64 m3/hr. Deep Shaft plant would require
less than 344 m2 (3,700 ft2) to enclose including preliminary treatment and
solids handling.
                                      348

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The power economy for the Deep Shaft plant is estimated at three times that
of a conventional plant.  The power economy for Deep Shaft plants is esti-
mated at 3.6 kg O2 transferred/kWh.

A sludge concentration of 5% by weight due to the thickening in the flotation
cells reduces sludge handling and disposal costs when compared to convention-
al systems using sedimentation which produces solids prior to dewatering or
stabilization at 1-2% concentration.
               TABLE 4.  DEEP SHAFT DAIRY PLANT COST EXAMPLE
Shaft Dimensions

Plant Surface Area

MLVSS

Sludge Production


Waste Sludge Concentration

Energy

Oxygen Transfer

Power Economy

Capital Cost
     Metric

  1.6 m x 250 m

     350 m2

   6500 mg/1

0.5 kg dry solids
 kg  8005  removed

       5%

     109 kW

 9,409 kg O2/day

  3.6 kg O2AWh

  $1.5 million
      U.S.A.

 63"  I.D. x 800'

     3700 ft2

    6500 mg/1

0.5 Ibs dry solids
 Ib BODr removed

        5%

      145 HP

 20,700 Ibs 02/day

5.95 Ibs O2/HP-hr.

   $1.5 million
The operating costs for the plant are outlined in Table 5.  An aeration cost
of 4.7£/m3 (17
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                 TABLE 5.   DEEP SHAFT DAIRY PLANT COST EXAMPLE
                              Operating  Cost/Yr.

                     Manpower                       10,000

                     Energy2                        25,000

                     Chemicals3                      1,000

                     Sludge Disposal4               60,000

                     Maintenance^                    7,500

                     Nutrients6                      7,000
                                                $110,500
                         Operating Cost Assumptions

          1.  Manpower based on h day attendance/day.

          2.  Energy based on $233/kWh  ($175/HP/yr.).

          3.  Chemicals based on alum @ 1 mg Al   /g MLSS.

          4.  Sludge disposal based on $0.27/metric ton-km hauling
             costs, assuming 16 km transport.
          5.  Maintenance based on h of one percent of capital cost.

          6.  Nitrogen required at 100:10:1.
BREWERY WASTEWATER TREATMENT

A Deep Shaft demonstration plant was constructed in 1976 at Molson's Brewery
in Barrie, Ontario, Canada to investigate the potential for the process to
treat brewery wastewater and to develop design information to allow full-scale
brewery Deep Shaft Effluent Treatment plants to be built.  Molson Breweries of
Canada Limited were attracted to the Deep Shaft Process in view of potential
savings in land, potentially less sludge for disposal and the apparent energy
savings that the technology offers.  A schematic of the existing wastewater
treatment plant is shown in Figure 2.  The existing extended aeration efflu-
ent treatment plant at Molsons has been very effective in meeting the exist-
ing 300 mg/1 8005 and 350 mg/1 TSS pretreatment guidelines established by the
City of Barrie.
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Operating experience has shown that the Molson's Deep Shaft can be effective-
ly used for biological treatment and sludge thickening or digestion of waste
activated sludge from the extended aeration plant.

The Deep Shaft hardware at Barrie is considerably different that the U-tube
pilot plant at Notre Dame du Bon Conseil, in that the Molson's Barrie plant
is a prototype.  The shaft consists of an 0.46 metre (18") I.D. steel casing
157 metres  (5101) deep grouted in a drilled hole 0.62 metres  (24") I.D.  Fol-
lowing the Deep Shaft headworks, a rectangular flotation cell receives parti-
ally degassed effluent.  The flotation cell has a top and bottom rake and
scraper arrangement.  The effluent from a flotation cell passes over an ad-
justable effluent weir.

Molsons provide approximately 9,042 m3 (62,500 USG) of surge tank capacity in
view of influent hydraulic and organic load fluctuations.

The ratio by weight of 6005 to ammonia, nitrogen and orthophosphate was
100:.31:.22.  It was determined eventually that this situation created a nu-
trient deficient biological condition in the shaft and resulted in unpredict-
able sludge behavior detrimental to the performance of the Deep Shaft Process.
Urea and phosphoric acid were added to bring the BOD to nitrogen to phosphorous
ratio to an acceptable level of 100:8.7:1.3 during the thirty-one day August/
September 1977 evaluation period.  It has been established that approximately
half of the nutrients are bioavailable in the effluent and therefore only half
of this value will have to be added.  Therefore, for the purpose of cost esti-
mates, the nutrient addition requirement of 2.5 kg of ammonia, nitrogen and
0.5 kg of orthophosphoric acid are required for 100 kg of BOD5 in the influ-
ent.

Pretreatment consists of screening which removes particles in excess of 0.64
cm  (V) in diameter.

The plant was commissioned in October 1976, however it was not until August
of 1977 after several developmental modifications that the plant could be
properly evaluated as a BOD and TSS removal system.

One basic difference between the Deep Shaft and extended aeration plant was
in the nature of the sludge.  There were never filamentous organisms in the
Deep Shaft sludge which was in complete contrast to the extended aeration
sludge.  The Deep Shaft sludge contains many types of protozoa including
stalked ciliates, which are indicative of a healthy biomass culture.  Specific
oxygen uptake rates were measured and were found to be in the range of 8-20
mg/g/hr.

The Deep Shaft plant at Barrie was operated in the flotation mode for six
months and the 8005 and TSS removal was within the City of Barrie industrial
bylaw effuent specifications of 300 mg/1 BOD5 and 350 mg/1 TSS.

The existing Deep Shaft mechanical configuration has not operated optimally
in a flotation mode for mechanical reasons; however, all parties involved are
in agreement that solids separation by means of flotation is entirely feasible.
                                     351

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 Modifications planned for April of 1978 will correct this problem resulting
 in excellent flotation.   The results of a 31 day intensive study evaluation
 period presented herein  are based on the flotation cell operating successful-
 ly in a clarifier mode.   Reliable flotation has been demonstrated at  the  Paris,
 Ontario Deep Shaft demonstration plant and at Emlichheim,  W.Germany as  discus-
 sed elsewhere(1)(4).   Therefore, Eco is confident that excellent flotation
 can be achieved at the Molson's Deep Shaft plant with some minor modifications.

 The successful operation of the Deep Shaft plant during the one  month test
 period between August 18 and September 18, 1977 is presented in  Table 6.
              TABLE 6.   MOLSONS1  DEEP SHAFT DEMONSTRATION  PLANT
                        ONE MONTH TEST PERIOD(6)
       Parameter      Influent      Effluent      Removal  Efficiency
                       (mg/1)         (mg/1)               (%)

       TBOD5             2624           109(a)             95.8

       TSS               1208           257                78.7
       (a)  soluble effluent BOD5  =  18
The operation parameters during  the one month  intensive test period are shown
in Table 7.

Settling rates in the clarifier  (ie.  flotation cell) are up to 4 m/hr. with
a stirred volume averaging 59 ml/g.   The presence of aluminum in the influ-
ent originating from the bottle  washing operation, accentuates the successful
coagulation and flocculation that occurs.

Total excess activated sludge wasted  as a result of biological treatment in
the Deep Shaft system over the 31 day period,  was estimated at 0.71 kg of
sludge/kg of BOD5 removed.

Power economy in the shaft was estimated at 1.7 kg of 8005 removedAWh (2.8
Ibs of BOD 5 removed/HP-hr.) on the average and 3.2 kg of BODg removed/kWh
(5.2 Ibs of BOD5 removed/HP-hr.) on peak loading.  However, since an equal
amount of air was being added at all  times, 0.2 - 1.4 kg of 8005 were oxidiz-
ed/kg of oxygen applied depending upon the BOD loading.  This is probably due
to the initial absorption of colloidal BOD5 onto the floe which is further
oxidized at a later time depending upon the sludge age.  Full-scale shaft
designs may include a device to vary  the air delivery in accordance with
changes in base line organic loading.
                                      352

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              TABLE 7.  MOLSONS' DEEP SHAFT DEMONSTRATION PLANT
                        ONE MONTH PERIOD(6)
Operational Parameter
Flow
Equalization
TBOD5(in)
TSS (in)
Oxygen Transfer
Power Economy
Sludge Production
Energy
Solids Concentration
BOD5:N:P
MLSS
Metric
5.73 m3/hr.
9,042 m3
2624 mg/1
1208 mg/1
500 kg/day
2.8 kg 02/kWh
0.71 kg sludge
kg BODg removed
7.5 kW
3-4%
100:8.7:1.3
5000 ppm
U.S.A.
0.036 mgd(USA)
50,000 gallons
2624 mg/1
1208 mg/1
1100 Ibs/day
4.6 Ibs O2/HP-hr.
0.71 Ibs sludge
Ib BOD5 removed
10 HP
3-4%
100:8.7:1.3
5000 ppm
Proper equipment installation and energy conservation measures could increase
power economics to 6 kg of BOD5/kWh  (10 Ibs of BOD5/HP-hr.) on full-scale
plant designs.

It is apparent that the flotation tank operating as a clarifier can operate
successfully at 8.59 m3/hr.  (37.5 US gpm) and 5,000 ppm MLSS.

The proper design of other pilot plants confirm that a proper anticipation of
air loading to the shaft and consequently its effect on gas stripping should
allow optimized flotation design of the Barrie Deep Shaft plant at 8.59 m3/hr.
(35 gpm) and 8,000 MLSS.

Complete equalization of the waste is not deemed necessary, even at higher
F/Ms, but it is recommended that 6 hours residence time be provided at the
Barrie plant.

Deep Shaft waste activated sludge stability has not been studied in detail,
however while operating the shaft as an aerobic digestor over a four day
period, it was observed that the specific oxygen uptake of the sludge could be
                                     353

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 reduced  by 88%  at  a  shaft  temperature of  20°C.  Laboratory studies indicate
 that  a 93% reduction is possible  at  25°C  and  this  is accomplished by a 34%
 weight reduction to  provide  a  sludge with only 62% MLVSS.

 Preliminary indications suggest that Deep Shaft activated sludge could be
 dewatered  to 20% solids using  a filter aid, such as ferric chloride.

 The Advantages  of  Flotation  Over  Sedimentation

 Flotation  generates  4% solids  and.allows  mixed liquor concentrations of 1%
 in the shaft at a  recycle  rate of 50%.  Sedimentation is generally limited to
 1.5%  settled solids  at .75%  mixed liquor  and  100%  recycle.  Sludge volumes
 are therefore,  drastically smaller when flotation  is used as a method of
 solids separation.   Subsequently, the cost of Deep Shaft systems using flo-
 tation is  lower.

 Flotation  rise  rates tend  to be 3 times faster than settling rates, which
 results  in smaller flotation cells and a  reduced length of time that the
 biomass  is outside of the  shaft.

 The advantages  of  flotation  are associated with the synergistic effect of
 using the  same  air for biological aeration, hydraulic circulation and as a
 driving  force for  solids separation.

 The more concentrated solids float is less expensive to process on vacuum
 filters  or  filter  presses  and  further reduces sludge handling and disposal
 costs.

 Economic Evaluation

A cost comparison between  the  Molsons1 extended aeration and Deep Shaft demon-
 stration plant  is presented  in Table 8.   It is interesting to note that the
 aeration costs  for the Deep  Shaft plant is 4.5 times less than the aeration
 costs for  the extended aeration plant.  The cost of pH control is not includ-
ed since excess carbon dioxide from the brewery process is used for pH con-
trol on the basic  side of  7.

The extended aeration does not include nutrient costs, but this is probably
offset by the fact that aerator usage may  not be optimized.
                                     354

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              TABLE 8.  MOLSONS1 DEEP SHAFT DEMONSTRATION PLANT
                        COST COMPARISON(6)
         Component           Deep Shaft            Extended Aeration
                           ($/l,000 kg BOD5)        ($/l,000 kg BOD5)

         Aeration1              7.51                     35.64

         Nutrients2             7.57                   undefined

         Digestion              5.83                   undefined
                               20.91J                    35.64
         1  Based on 30.33 kW @ 1.6£AWh.

         2  Based on $4.84/1,000 kg BOD5 ($2.20/1,000 Ibs BOD5) for
            ammonia nitrogen and $2.73/1,000 kg BOD5 ($1.24/1,000 Ibs
            BOD^) for phosphoric acid.

         3  Relates to $1.80/1,000 m3 (26.2C/1,000 USG).
Full-Scale Deep Shaft Brewery Plant Cost Estimate

Table 9 describes the cost of a full-scale Deep Shaft plant designed on the
basis of the design information developed at the Molson's Deep Shaft demon-
stration plant.

The hypothetical plant is assumed to consist of screening, comminution, grit
removal, equalization, neutralization. Deep Shaft aeration, flotation, chemi-
cal addition, vacuum filtration and sludge disposal.

The Deep Shaft cost includes the installed cost of the aeration and solids
separation portion of the plant assuming all front-end components are essen-
tially equal for all biological systems.  The Deep Shaft Process however, does
not require primary sedimentation in advance of it.

Table 10 and 11 offers a breakdown of energy and operating costs for the two
Deep Shaft options investigated.  The roughing plant will, in fact, experience
a large degree of BOD^ removal but a large amount of solids would be slipped
to the sewer.

The total Deep Shaft costs estimated at 2.5 and 2.75 million dollars for
roughing and complete treatment are expected to represent 43 and 51% respec-
tively of the total plant capital costs.  The Deep Shaft operating costs are
expected to represent 50% of the total operating cost as demonstrated in
Table 11.


                                     355

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 TABLE  9.   DEEP  SHAFT BREWERY APPLICATION COST EXAMPLES(6)
Parameter

Mean Flow
Peak Flow
Organic Loading
MLSS
Energy
(b)
Operating Cost
Cost/Flow
Deep Shaft Portion
Deep Shaft Cost
Deep Shaft Plant Area
Units

m3/hr.
m3/hr.
kg BODs/day
mg/1
kW
$/day
$/l,000 m3
% of total cost
$ million
m2
Duty
Roughing
(300/300)
636
700
14,545
8,000
224
704.05
1.24
43
2.5
743
Complete
(50/50)
636
700
14,545
8,000
242
1,107.76
1.85
51
2.75
743
TABLE 10.  DEEP SHAFT BREWERY APPLICATION COST ESTIMATE
(a) Energy

Deep Shaft Aeration
Lighting
Scrapers
Sludge Pumps
Fans
Instruments
Duty
Roughing
(300/300)
191.00
6.75
4.50
15.00
7.00
0.75

Complete
(50/50)
210.00
6.75
4.50
15.00
7.00
0.75
 TOTAL
225.00 kW
244.00 kW
                          356

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          TABLE 11.  DEEP SHAFT BREWERY APPLICATION COST EXAMPLE
(b) Operating Cost
(S/day)
Energy
Chemicals/Nutrients
Flotation Aids
Manpower
Sludge Handling
Sludge Disposal
TOTAL
Roughing
(300/300)
85.82
110.08
NIL
108.00
263.65
136.50
$704.05/day
Duty
Complete
(50/50)
93.02
110.08
256.00
108.00
356.16
184.50
$l,107.76/day
CONCLUSIONS

Eco has established the basic design parameters for full-scale brewery and
dairy Deep Shaft effluent treatment plants.

The subsequent costs of construction and operation can be accurately project-
ed for full-scale brewery and dairy Deep Shaft effluent treatment plants.

Full-scale Deep Shaft effluent treatment plants can now be built to treat
dairy and brewery effluent to municipal pretreatment levels of 200 mg/1 BOD^
and 200 mg/1 TSS and levels of 50 mg/1 BOD5 and 50 mg/1 TSS for direct dis-
charge .

Improvements in suspended solids separation should result in an ability to
meet 30 mg/1 TSS in the future.

The major advantages associated with utilizing the technology to treat food
processing wastewater include possible reductions in capital cost, lower
power costs and space economy.

The technology can be used in urban centres because it can be inexpensively
enclosed and is odorless and noiseless (ie. less than 85 db).
                                     357

-------
                               BIBLIOGRAPHY
1.  Bolton, D.H., Bouchard, J.P., and Hines, D.A.  "The Application of the
    ICI Deep Shaft Process to Industrial Effluents".  31st Annual Purdue
    Industrial Waste Conference, 4-6 May 1976, La Fayette, Indiana, U.S.A.

2.  Bradley, B.J.  "The ICI Deep Shaft Effluent Treatment Process".
    29th Annual Atlantic Canada Section, AWWA Meeting, 12-15 September 1976,
    Halifax, Nova Scotia, Canada.

3.  Bolton, D.H., and Ousby, J.L.  "The ICI Deep Shaft Effluent Treatment
    Process and its Potential for Large Sewage Works".  Workshop on Large
    Wastewater Treatment Plants, International Association on Water
    Pollution Research, 8-12 September 1975, Vienna, Austria.

4.  Chisholm, K.A., and Sandford, D.S.  "The Treatment of Municipal Wastewater
    Using the ICI Deep Shaft Process".  29th Annual Western Canada Water &
    Sewage Treatment Conference, 28-30 September 1977, Edmonton, Alberta,
    Canada.

5.  Knudsen, F.B., Kuslikis, B.P., Pollock, D.C., and Wilson, M.A.
    "Application of the Deep Shaft Process to the Treatment of Brewery
    Effluents".   Water, Wastewater Equipment Manufacturers Association
    Conference,  11 April 1978, St. Louis, Missouri, U.S.A.

6.  Knudsen, F.B.  "Brewery Effluent Treatment by the ICI Deep Shaft Process".
    Montreal Chapter of the ASBC, 17 March 1978, Montreal, P.Q., Canada.
                                     358

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                     NINTH FOOD WASTE SYMPOSIUM

                          REGISTRATION LIST
 I.  L.  ABERCROMBIE
 Sweco  Inc.
 P.O. Box  4151
 Los Angeles, CA  90051

 WALTER ADAMS
 Sterling  Colorado Beef Co.
 Box 1728
 Sterling, CO  80751

 MEL ALSAGER
 J. R.  Simplot
 Box 27
 Boise, ID 83707

 HAROLD BARNETT
 Nat'l. Marine Fisheries Service
 2725 Montlake Blvd. E.
 Seattle,  WA  98112

 EDWARD BARRERA
 Ranch Style Inc.
 Box 1867
 Fort Worth, TX  76101

 DONALD J. BAUMANN
 Creighton University
 2500 California Street
 Omaha, NE  68131

MARTHA BEACH
N-CON Systems
 308 Main Street
New Rochelle, NY  10801

RICHARD T. BEAUPRE
 Capitol Consultants Inc.
 1627 Lake Lansing Road
Lansing, MI  48912

BARRETT E. BENSON
U.S. EPA - NEIC
Bldg.  53, Denver Federal Center
Denver, CO  80225
EUGENE E. BERKAU
U.S. EPA, IPCD
Industrial Environmental Res. Lab.
Cincinnati, OH  45268

JAMES R. BOYDSTON
U.S. EPA, IPCD
200 S.W. 35th Street
Corvallis, OR  97330

G. M. BROOKS
Mississippi Cooperative Ext. Serv.
Food and Fiber Center
P.O. Box 5426
Mississippi State, MS  39762

W. E. BROOKS
Astro Met
Box 520
Wooster, OH  44691

WILLIAM BROTHERTON
International Co-op
P.O. Box 1378
Grand Forks, ND  58201

ROBERT 0. BROWN
Robert 0. Brown Co.
4200 Cedar Avenue South
Minneapolis, MN  55407

ROLF BROWN
Robert 0. Brown Co.
4200 Cedar Avenue South
Minneapolis, MN  55407

CLIFFORD BRUELL
Adolph Coors Company
Mail #203
Golden, CO  80401

JOHN R. BURGESON
M & I, Inc.
4710 South College
Fort Collins, CO  30521
                                359

-------
 DONALD G. BZDYL
 Envirotech Corporation
 301 S. Hicks Road
 Palatine, IL  60067

 ALAN D. CARLSON
 John Morrell & Co.
 208 S. LaSalle Street
 Chicago, IL  60604

 ROBERT CASCIANO
 Airco Industrial Gases
 575 Mountain Avenue
 Murray Hill, NJ  07974

 SOT CHIMONAS
 J.  R.  Simplot Co.
 P.O.  Box 1059
 Caldwell, ID  83605

 H.  S.  CHRISTIANSEN
 Carnation
 5045  Wilshire Boulevard
 Los Angeles,  CA 90036

 0.  A.  CLEMENS
 SESCO
 1919  Swift  Drive
 Oakbrook, IL  60521

 WALTON H. CRAIG
 Sharpies-Stokes  Division
 Pennwalt  Corporation
 111 Windsor  Drive
 Oak Brook,  IL  60521

 DONALD DALTON
 Valmac Industries
 Box 842
 Russellville, AR 78629

 SATYENDRA M.  DE
 W.  D.  Byron  & Sons, Inc.
Williamsport, MD 21795

 C.  ROY DEAN
MBPXL  Corporation
P.O. Box 2519
Wichita, KS   67201
 ROBERT DELONG
 Jeno's Inc.
 4125  Pipestone  Road
 Sodus, MI   48126

 ROBERT E. DIEHL
 Van Camp Sea Food Company
 11555 Sorrento  Valley Road
 San Diego,  CA   92121

 SUSAN DOBBERSTEIN
 Foremost Foods  Co.
 6363  Clark Avenue
 Dublin, CA  94566

 KENNETH A. DOSTAL
 U.S.  EPA, IERL
 Food  and Wood Products Branch
 200 S.W. 35th Street
 Corvallis, OR   97330

 GARY  DOWNING
 Adolph Coors Company
 Mail  #703
 Golden, CO  80401

 CHARLES B. DULL
 James  Allan & Sons
 P.O.  Box 8329
 Stockton, CA  95208

 ROBERT  E.  DUNNICK
 Hanover Brands, Inc.
 P.O.  Box 334
 Hanover, PA  17331

 JIM EISINGER
 C & D Foods, Inc.
 2319  Raymond Avenue
 Franksville, WI  53126

 THOMAS E.  ELLIOTT
 Swift & Company
 115 W. Jackson Boulevard
 Chicago, IL  60604

DAVID B. ERTZ
Edward C.  Jordan Co.,  Inc.
P.O.  Box 7050 Downtown Station
Portland,  ME  04112
                                 360

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LARRY A. ESVELT
Esvelt Environmental Engineering
East 7905 Heroy
Spokane, WA  99206

ANN E. FARRELL
J. M. Montgomery Consulting Engineers
1990 N. California Boulevard
Walnut Creek, CA  94596

R. THOMAS FITZGERALD
Furman Canning Co.
R. D. #2
Northumberland, PA  17857

E. L. FOERSTER, SR.
Consulting Engineer
Box 779
Harrisonburg, VA  22801

CLYDE W. FULTON
Stanley Associates Engineering Ltd.
505 - 5th Avenue S.E.
Calgary, Alberta  T2G OE9

THOMAS M. FURLOW
Jordan, Jones & Goulding, Inc.
Suite 200, 2000 Clearview Ave., N.E.
Atlanta, GA  30340

TOM GALLO
Eco Research Ltd.
45 Sheppard Avenue E.
Willowdale, Ontario  M2N 2Z9

CHARLES GOBLE
Levelland Vegetable Oil, Inc.
P.O. Drawer N
Levelland, TX  79336

HAROLD I. GOLDSMITH
Kraft, Inc.
801 Waukegan Road
Glenview, IL  60025

PAUL H. M. GUO
Environment Canada
1756 Old Waterdown Road
Burlington, Ontario  L7R 4A6
C. FRED GURNHAM
Gurnham & Associates, Inc.
223 West Jackson Boulevard
Chicago, IL  60606

SUZAN A. GUTTORMSEN
Brown & Caldwell
100 W. Harrison
Seattle, WA  98119

CHARLES A. HAAS
Wells Engineers, Inc.
P.O. Box 177
Gering, NE  69341

DASEL E. HALLMARK
DSA, Inc.
2186 So. Holly
Denver, CO  80222
TOM HARDING
Mountaire Poultry,
123 W. Park
DeQueen, AR  71832
Inc.
J. M. HASKILL
Fisheries & Environment Canada
Water Poll. Control Directorate
Ottawa, Ontario  K1A 1C8

KERRY D. HERD
Techna-Dyne
7204 So. Garfield
Littleton, CO  80122

J. C. HESLER
The Greyhound Corp. (Armour)
202 E. Voltaire
Phoenix, AZ  85022

JIM HETRICK
Combustion Engineering Bauer
P.O. Box 722
Dana Point, CA  92629

M. D. HIXSON
Sweco Inc.
6033 E. Bandini Blvd.
Los Angeles, CA  90051
                                 361

-------
 HOEFLER
 Alwatech A/S
 Harbitzalleen 3
 Oslo 2, Norway

 A. HOPWOOD
 Alwatech UK
 33 A. Park Parade
 Hazlemere, Highwycombe UK

 JOHN HORNBECKER
 Fluid Systems Inc.
 1777 So.  Bellaire
 Denver, CO  80222

 H. C. 1SAKSEN
 Alwatech A/S
 Oslo, Norway

 WILLIAM R. ISHERWOOD
 Ponder Engineering  & Survey
 P.O.  Box 236
 Daphne, AL  36526

 NABEEL L.  JACOB
 Nat'l.  Food Processors  Association
 1950 Sixth Street
 Berkeley,  CA  94710

 H.  R.  JAKUBIEC
 Canada Packers Limited
 95 St.  Clair Avenue West
 Toronto, Ontario  M4V 1P2

 C.  J.  JOST,  JR.
 Anheuser-Busch, Inc.
 721 Pestalozzi, Bldg. 3
 St. Louis, MO  63118

 ROBERT  M.  KEDDINGTON
 K  & P  Inc.
 3331  So. 9th E.,  Suite  210
 Salt Lake  City, UT   84106

 JOHN  S. KEITH
 Inmont  Corporation
 609 Lafayette Avenue
 Hawthorne, NJ  07506

 RALPH KENWORTHY
John Inglis  Frozen Foods Company
 300 Daly Avenue
Modesto, CA   95353
 LLOYD H.  KETCHUM,  JR.
 University  of Notre Dame
 Department  of Civil Engineering
 Notre Dame,  IN   46556

 STEPHEN E.  KING
 Union Carbide Corporation
 17  Executive Park  Dr., N.E.
 Atlanta,  GA 30351

 WILLIAM KOPET
 Carborundum Co.
 132 Helen Way
 Escondido,  CA  92025

 VACLAV KRESTA
 Department  of the  Environment
 P.O.  Box  6000
 Fredericton, New Brunswick
 Canada

 ED  KROEKER
 Stanley Associates Engrg. Ltd.
 11748 Kingsway Avenue
 Edmonton, Alberta  T5G 0X5

 KENNETH B. KYTE
 Sharpies  Stokes Division
 Pennwalt  Corporation
 111 Windsor  Drive
 Oak Brook, IL  60521

 KEN LACONDE
 SCS Engineers
 4014  Long Beach Boulevard
 Long  Beach, CA  90807

 LARRY F. LAFLEUR
 Domingue, Szabo & Assoc., Inc.
 117 Calco Boulevard
 Lafayette, IN  70505

 C. P.  LAND
 Kahn's Company
 3241 Spring Grove Avenue
 Cincinnati, OH  45225

ROBERT C.  LANDINE
ADI Limited
P.O. Box 44
Fredericton, N.B.  E3B 4Y2
                                 362

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PETER J. LANDWEHR
Oscar Mayer & Co.
Box  7188
Madison, WI  53707

PAUL F. LEAVITT
Gerber Products Co.
445  State Street
Fremont, MI  49412

K. V.  LENSMEYER
Ralston Purina Co.
Checkerboard Square
St.  Louis, MO  63188

HUDA S. LILLARD
USDA,  SEA, Russell Research Center
P.O.  Box 5677
Athens, GA  30604

ROBERT G. LISTER
American Can Company
American Lane
Greenwich, CT  06830

R. D.  LONGE
American Stores Co.
200  S. 2nd
Lincoln, NE  68507

DUGAL  R. MACGREGOR
Agriculture Canada
Research Station
Summerland, B.C.  VOH 1ZO

R. B. MAGUIRE
Agripac Inc.
P.O. Box 5346
Salem, OR  97304

PAUL M. MARTIN
Victor F. Weaver, Inc.
403 S. Custer Avenue
New Holland, PA  17557

JAMES L. MASON
Wastewater Operator II
Wampler Foods, Inc.
Hinton, VA  22831
ROBERT E. MEANS
Bouillon, Christofferson and
  Schairer
505 Washington Building
Seattle, WA  98101

VON T. MENDENHALL
Utah State University
Nutrition & Food Science Dept.
Logan, UT  84322

MIKE MEYER
C & D Foods, Inc.
2319 Raymond Avenue
Franksville, WI  53126

BYRON F. MILLER
Colorado State University
Department of Animal Sciences
Fort Collins, CO  80523

LARRY W. MILLER
Country Pride Foods Ltd.
P.O. Box 1997
El Dorado, AR  71730

JERRY D. MINOR
Kramer, Chin & Mayo
535 S.W. 4th
Corvallis, OR  97330

T. L. MCANINCH
Birko Chemical Corporation
P.O. Box 1315
Denver, CO  80201

GERALD N. MCDERMOTT
Procter & Gamble Co.
Hillcrest Tower
7162 Reading Road
Cincinnati, OH  45222

JOE H. MCGILBERRY
Mississippi Coop. Extension Serv.
Food and Fiber Center
P.O. Box 5426
MS State, MS  39762
                                 363

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 DAVID MCNAIR
 Allied Mills Inc.
 110 N. Wacker Drive
 Chicago, IL  60606

 JACK MCVAUGH
 Envirex Inc.
 1901 S.  Prairie Avenue
 Waukesha,  WI  53186

 CARL E.  NALL
 Pacific Egg and Poultry Association
 9800 S.  Sepulveda, Suite 618
 Los Angeles, CA 90045

 DAVID B. NELSON
 Monsanto Research  Corporation
 1515 Nicholas Road
 Dayton,  OH  45407

 PER NETTLI
 Alwatech A/S
 Oslo,  Norway

 STEPHEN  NUTT
 Dearborn Envir.  Consulting  Services
 3451 Erindale Station  Road
 Mississauga,  Ontario   L5C 2S9

 JAMES  H. DATES
 J.  R.  Simplot Co.
 Box 1029
 Caldwell,  ID  83605

 GUS ORTENGREN
 Alwatech
 1550  So. Pearl  Street
 Denver, CO   80210

 GAYLORD M. PALMER
 Foremost Foods  Company
 6363 Clark Avenue
 Dublin, CA   94566

 CLINTON E. PARKER
U.S. EPA, lERL-Ci
5555 Ridge Avenue
 Cincinnati, OH  45268
 JOHN P.  PILNEY
 MRI, North  Star  Division
 10701 Red Circle Drive
 Minnetonka, MN   55343

 BRIAN W. RAINES
 National Pet Food  Corporation
 P.O.  Box 788
 Long Beach, CA   90801

 ERNEST R. RAMIREZ
 Swift &  Co.
 1919 Swift Drive
 Oak  Brook, IL  60521

 JAMES S. RAUH
 Olin Water Services
 51 Corporate Woods
 9393 West 110th  Street
 Overland Park, KS  66210

 MILTON D. REDICK
 Capitol Consultants Inc.
 1627  Lake Lansing Road
 Lansing, MI  48912

 ROBERT RENNER
 M &  I, Inc.
 4710  South College
 Fort  Collins, CO  80521

 JO ANN ROBISON
 Boise  Cascade
 Box  851
 Stanfield, OR  97875

 CARL  T. ROLLINS
 DuBois
 3630  E. Kemper Road
 Sharonville, OH  45241

WALTER W. ROSE
Nat'l. Food Processors Assoc.
 1950  Sixth Street
 Berkeley, CA  94710

JOHN ROSENAU
Dept. of Food & Agric.  Engrg.
University of Massachusetts
Amherst, MA  01003
                                364

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 D.  S.  SANDFOKD
 Eco Research  Limited
 6940 Fisher Road,  S.E.
 Calgary,  Alberta T2H OW3

 NEIL SCHACHT
 Con Agra  Poultry
 P.O. Box  2084
 Decatur,  AL  35602

 CARL SCHAFER
 U.S. EPA,  IEPD
 401 M  Street, SW
 Washington, DC  20460

 LANNY A.  SCHMID
 Spencer Foods Inc.
 Box 544
 Schuyler,  NE  68661

 CURTIS SCHMIDT
 SCS Engineers
 4014 Long  Beach Boulevard
 Long Beach, CA  90807

 MARTIN D.  SCHWARTZ
 Arthur G.  McKee
 10  So. Riverside Plaza
 Chicago, IL   60606

 KHEM SHAHANI
 Department of Food Science
 University of Nebraska
 Lincoln, NE  68583

 RONALD D.  SCINOCCA
 Jeno's Inc.
 525 Lake Avenue So.
 Duluth, MN 55801

 ROBERT J.  SHERMAN
 Alwatech Division
A.  L. Laboratories, Inc.
 452 Hudson Terrace
 Englewood  Cliffs, NJ  07632

JOSEPH SILVIA
Envirex Inc.
 1901 S. Prairie Avenue
Waukesha,  WI  53186
K. LYNN SIRRINE
The R. T. French Co.
434 So. Emerson
Shelley, ID  83274

NORMAN J. SMALLWOOD
Lou Ana Foods, Inc.
P.O. Box 591
Opelousas, LA  70570

JOHN SMOLIK
Corning Glass Works
Corning, NY  14830

STEVEN M. SPANGLER
Van Camp Sea Food Company
11555 Sorrento Valley Road
San Diego, CA  92121

J. H. STANFIELD
Alpha Research & Technology
3955 B Newport Street
Denver,.CO  80207

ROBERT M. STEIN
AWARE Inc.
Box 40284
Nashville, TN  37204

PAUL STEPHENSON
Morrison, Cooper & Partners
P.O. Box 6214
Wellington, New Zealand

RICHARD W. STERNBERG
U.S. EPA
401 M Street, SW
Washington, DC  20460

DALE W. STORM
Illinois Water Treatment Co.
4669 Shepherd Trail
Rockford, IL  61105

A. J. SZABO
Domingue, Szabo & Assoc., Inc.
P.O. Box 52115
Lafayette, LA  70505
                                 365

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 DONALD J. THIMSEN
 General Mills, Inc.
 P.O. Box 1113
 Minneapolis, MN  55440

 HAROLD W. THOMPSON
 U.S. EPA, IERL
 Food and Wood Products Branch
 200 S.W. 35th Street
 Corvallis,  OR  97330

 STEVE THURLOW
 Stephen Thurlow Company,  Inc.
 P.O. Box 9520
 Seattle, WA  98109

 JON TIENSTRA
 Allen Products Company, Inc.
 P.O. Box 2187
 Allentown,  PA  18801

 CALVIN R. TININENKO
 Farmland Foods,  Inc.
 P.O. Box 7527, Dept.  222
 Kansas City,  MO  64116

 E.  TONSETH
 Alwatech
 1550 So.  Pearl Street
 Denver,  CO   80210

 ALAN TUROVER
 Castle & Cooke Co.
 5th  & Virginia
 San  Jose, CA 95112

 STEVEN L. TYLER
 A. E.  Staley  Mfg. Co.
 Box  432
 Monte Vista,  CO  81144

 RICHARD  V. VANCE
 Anheuser-Busch, Inc.
 721  Pestalozzi Street
 St..  Louis, MO  63118

 R. H. VICKERMAN
P.O.  Box 261
Hardisty, Alberta  TOB 1VO
 V.  H.  VODRA
 Birko  Chemical  Corporation
 P.O. Box 1315
 Denver,  CO   80201

 JOHN F.  H.  WALKER
 Arthur G. McKee & Co.
 10  S.  Riverside Plaza
 Chicago,  IL 60606

 GENE WALRATH
 C & D  Foods, Inc.
 2319 Raymond Avenue
 Franksville, WI 53126

 J.  C.  WEISEL
 Hydroscience, Inc.
 2815 Mitchell Drive, Suite 124
 Walnut Creek, CA  94598

 W.  JAMES WELLS, JR.
 Wells  Engineers, Inc.
 515 North 87th  Street
 Omaha, NE   68114

 ROGER  WILKOWSKE
 USDA,  Extension
 Science and  Education Admin.
 Washington,  DC  20250

 H.  KIRK WILLARD
 U.S. EPA, IERL
 Food and Wood Products Branch
 Cincinnati, OH  45268

 LARRY  WILLIAMS
 Holly  Farms  of Texas Inc.
 P.O. Box 789
 Center, TX   75945

 FELON  R. WILSON
 Domingue, Szabo & Associates
 117 Calco Boulevard
 Lafayette, LA   70505

MIKE WINTER
Wemco Division, Envirotech
Box 15619
 Sacramento, CA  95608
                                366

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SHELLEY WIRSIG
Adolph Coors Co.
Department 300
Golden, CO  80401

JACK L. WITHEROW
U.S. EPA, IERL
Food and Wood Products Branch
200 S.W. 35th Street
Corvallis, OR  97330

PING-YI YANG
University of Hawaii
3050 Maile Way
Honolulu, HI  96822

WILLIAM D. RUTZ
MAPCO Inc.
Process & Pollution Controls Div.
1800 South Baltimore Avenue
Tulsa, OK  74119
                               367

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                                   TECHNICAL REPORT DATA
                            (Please read Instructions on the reverse before completing)
 1. REPORT NO.
  EPA-600/2-78-188
                              2.
                                                            3. RECIPIENT'S ACCESSION NO.
4. TITLE AND SUBTITLE
  PROCEEDINGS NINTH NATIONAL  SYMPOSIUM ON FOOD
  PROCESSING WASTES— March 29 - 31, 1978,
                       Denver,  Colorado
                                                            5. REPORT DATE
               August 1978 Issuing  date
             6. PERFORMING ORGANIZATION CODE
7. AUTHOR(S)
                                                           8. PERFORMING ORGANIZATION REPORT NO.
9. PERFORMING ORGANIZATION NAME AND ADDRESS
  Food  and Wood Products Branch
  Industrial Environmental  Research Laboratory
  Corvallis, Oregon  97330
             10. PROGRAM ELEMENT NO.

                   1BB610
             11. CONTRACT/GRANT NO.
 12. SPONSORING AGENCY NAME AND ADDRESS
 . Industrial  Environmental  Research Lab-Cinci, OH
  Office  of Research and Development
  U.S.  Environmental Protection Agency
  Cincinnati,  OH  45268
             13. TYPE OF REPORT AND PERIOD COVERED

                         "i nm PTr»r*^p*HT n gg	
             14. SPONSORING AGENCY CODE

                   EPA/600/12
 15. SUPPLEMENTARY NOTES Additional sponsors include:  National Food Processors  Association,
  American Meat Institute,  Southeastern Poultry and  Egg Association, Western States
  Meat  Packers Association,  Pacific Egg and Poultry  Association, and American Society
 16. ABSTRACT  Of Agricultural  Engineers.

  The Proceedings contains  copies of the 24 papers presented at the Ninth National
  Symposium on Food Processing Wastes.  Subjects  included:  processing modifications,
  product  and by-product recovery, wastewater  treatment, water recycle and  water
  reuse for several segments of the food processing  industry.  These segments
  included:  red meat and poultry, seafood, dairy, fruit, and vegetable.

  Attendance at the two and one-half- day Symposium was  approximately 170 with good
  representation by industry,  universities, consulting  firms, as well as state and
  Federal  agencies.
17.
                                KEY WORDS AND DOCUMENT ANALYSIS
                  DESCRIPTORS
b.lDENTIFIERS/OPEN ENDED TERMS  C. COS AT I Field/Group
   Industrial Wastes, Waste  Water, Food
   Processing, Byproducts
 Process Modifications,
 Water  Reuse,  Water
 Recycle
   13/B
18. DISTRIBUTION STATEMENT


      Release Unlimited
19. SECURITY CLASS (This Report)
  Unclassified
21. NO. OF PAGES
    374
20. SECURITY CLASS (This page)
  Unclassified
                           22. PRICE
EPA Form 2220-1 (9-73)
                                            368
                                                                    ft U.S. GOVERNMBII PRINTING OFFICE: 1978—657-060/1496

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