Group 1, Phase II





        Development Document for



 Proposed Effluent Limitations Guidelines



  and New Source Performance Standards




                  for the
                POULTRY
              Segment of the
   MEAT PRODUCT AND RENDERING PROCESS
          Point Source Category

UNITED STATES ENVIRONMENTAL PROTECTION AGENCY



                APRIL 1975

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          DEVELOPMENT DOCUMENT

                  for

  PROPOSED EFFLUENT  LIMITATIONS  GUIDELINES

                  and

    NEW SOURCE PERFORMANCE STANDARDS

                for the

POULTRY PROCESSING POINT SOURCE  CATEGORY
            Russell E. Train
             Administrator

             James L.  Agee
 Assistant Administrator for Water and
          Hazardous Materials
            .  Allen Cywin
 Director, Effluent Guidelines Division

            Jeffery D. Denit
            Project Officer
             April  1975

      Effluent Guidelines Division
 Office of Water and Hazarous Materials
 U. S. Environmental Protection Agency
        Washington, D. C.  20460

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                            ABSTRACT

This document presents the findings of an extensive study of  the
poultry  processing  industry  by  the  Environmental  Protection
Agency  for  the  purpose  of  developing  effluent   limitations
guidelines, limitations of performance and pretreatment standards
for  the  industry, to implement Sections 301, 304(b) 307 and 306
of the Federal Water Pollution Control  Act  Amendments  of  1972
(the "Act") ,

The  poultry  processing plants included in the study were plants
that slaughter, dress and/or further process  poultry,  including
rabbits  and  other  small  game;  plants  that  process  eggs or
manufacture such products as canned  soups  and  TV  dinners  are
excluded  from  the  study.   There are five subcategories in the
poultry processing industry; four  are  based  on  type  of  bird
slaughtered, and one is plants that further process only.

Effluent  limitations  are  set  forth for the degree of effluent
reduction  attainable  through  the  application  of  the   "Best
Practicable  Control  Technology  Currently  Available,»  and the
"Best Available Technology Economically Achievable,"  which  must
be  achieved  by existing point sources by July 1, 1977, and July
1, 1983, respectively.  The "Standards  of  Performance  for  New
Sources"  set  forth  the  degree  of effluent reduction which is
achievable  through  the  application  of  the   best   available
demonstrated control technology, processes, operating methods, or
other  alternatives.   The  proposed  recommendations require the
best biological  treatment  technology  currently  available  for
discharge  into  navigable  water bodies by July 1, 1977, and for
new  source  performance   limitations.    This   technology   is
represented   by   water  recirculation  in  flow  away  systems,
anaerobic  plus  aerobic  lagoons  or   their   equivalent,   and
chlorination.   The  cost  to the industry to implement the waste
treatment to achieve the 1977 limitations is estimated  at  $13.9
million.  New source limitations incorporate the 1977 limitations
and an ammonia limitation.  The recommendations for July 1, 1983,
are  for  the best biological treatment and in-plant controls, as
represented by dry  offal  handling  systems;  improved  in-plant
primary   treatment   such   as   dissolved  air  flotation,  and
microscreen, sand filter, or equivalent in  solids  controls;  in
addition  to  the  waste  treatment  system required for the 1977
limitations.  Ammonia reduction by nitrification or air stripping
will be required if the effluent exceeds the ammonia limitations.
When sufficient suitable land  is  available,  land  disposal  by
irrigation  with  no  discharge  may be the most economical waste
treatment option.  The cost for the 1983 limitations is estimated
at $38.6 million for the poultry industry.

Supportive data and rationale for  development  of  the  proposed
effluent limitations and limitations of performance are contained
in this report.

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                            CONTENTS

Section

I.         CONCLUSIONS                                              *

II.        RECOMMENDATIONS                                          3

III.      INTRODUCTION                                             5

          Purpose and Authority                                    5

          Summary of Methods Used for Development of the Effluent
          Limitations Guidelines and Standards of Performance      6

          General Description of the Industry                     10

          General Process Description                             17

          Poultry Slaughter Manufacturing Processes               21

               Receiving                                          21
               Killing and Bleeding                               22
               Defeathering                                       23
               Evisceration                                       24
               Chilling and Packaging                             25
               Subprocesses                                       2&

          Poultry Further Processing Manufacturing Process        27

               Receiving, Storage, and  Shipping                   27
               Thawing                                            2S
               Cutting and Boning                                 29
               Grinding, Chopping, and  Dicing                     29
               Cooking                                            30
               Batter and Breading                                31
               Mixing and Blending                                32
               Stuffing and Injecting                             32
               Canning                                            33
               Final Product  Preparation                         35
               Freezing                                           35
               Packaging                                           36

          Anticipated Industry  Growth                             36

IV.       INDUSTRY CATEGORIZATION                                 37

          C at egori zat ion                                          3 7

          Rationale for Categorization                            38

               Type of Raw Material                                38
               Finished Product                                   40
               Processing Operations                               41
               Plant Size                                          41

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                      CONTENTS  (Continued)
oAction
V.
VI.
VII.
      Plant Age and Location
      Waste Water Characteristics and Treatability

WATER USE AND WASTE CHARACTERIZATION

Waste Water Characteristics

     Raw Waste Characteristics
     Discussion of Raw Wastes
     Process Waste Water Flow Diagrams

Water Use-waste Load Relationships

Sources of Waste Water and Waste Load

     Killing and Bleeding
     Scalding
     Defeathering
     Evisceration
     Chilling
     By-Product Recovery
     Further Processing
     Rendering Plant Condensate and Condenser  Water

SELECTION OF POLLUTANT PARAMETERS

Selected Parameters

Rationale for Selection of Identified Parameters

     5-Day Biochemical Oxygen Demand  (BOD5)
     Chemical Oxygen Demand  (COD)
     Suspended Solids  (TSS)
     Total Dissolved Solids  (TDS)
     Total Volatile Solids  (TVS)
     Grease
     Ammonia Nitrogen
     Kjeldahl Nitrogen
     Nitrates and Nitrites
     Phosphorus
     Chloride
     Fecal Coliform
     pH, Acidity, and Alkalinity
     Temperature

CONTROL AND TREATMENT TECHNOLOGY

Summary

In-Plant Control Techniques

     By-Product Recovery  (Screening)
42

45

45

45
53
59

59

62

62
64
64
65
66
66
67
68

69

69

69

69
71
71
73
74
75
75
77
77
78
79
79
80
81

83

83

83

86

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                         CONTENTS (Continued)
St.-r I ion                                                         Page

VLi.     CONTUOL AND TREATMENT TECHNOLOGY (Continued)

         In-Plant  Primary Treatment                            89

               Flow Equalization                                39
               Screens                                          89
               Catch Basins                                     90
               Dissolved Air Flotation                          91
               Electrocoagulation                               95

         Waste Water Treatment Systems                         97

               Anaerobic Processes                              97
               Aerated Lagoons                                 100
               Aerobic Lagoons                                 100
               Activated Sludge                                102
               Extended Aeration                               104
               Rotating Biological Contactor                   105

         Advanced Waste Treatment                                 107

               Chemical Precipitation                          107
               Sand Filter                                     108
               Microscreen/Microstrainer                       113
               Nitrogen Control                                117
               Nitrification/Denitrification                   121
               Ammonia Stripping                               123
               Breakpoint Chlorination                         124
               Spray/Flood Irrigation                          125
               Ion Exchange                                    129

VIII.    COST, ENERGY, AND NONWATER QUALITY ASPECTS           133

         Summary                                              133

         "Typical" Plant                                      137

         Waste Treatment Systems                              140

         Treatment and Control Costs                          143

               In-Plant Control Costs                          143
               Investment Costs Assumptions                    143
               Annual Costs Assumptions                        146

         Energy Requirements                                  147

         Nonwater Pollution by Waste Treatment Systems       149

               Solid Wastes                                    149
               Air Pollution                                   151
               Noise                                           152
                                  Vll

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          Introduction
                      CONTENTS  (Continued)

Section

IX.       EFFLUENT REDUCTION ATTAINABLE THROUGH THE APPLICATION
          OF THE BEST PRACTICABLE CONTROL TECHNOLOGY CURRENTLY
          AVAILABLE—EFFLUENT LIMITATIONS GUIDELINES                153
                                                                    153
          Effluent Reduction Attainable Through the Application
          of Best Pollution control Technology Currently
          Available                                                 154

          Identification of Best Practicable Control Technology
          Currently Available                                       158

          Rationale for the Selection of Best Practicable
          Control Technology Currently Available                    159

          Size, Age, Processes Employed, Location of Facilities     ieo

          Total Cost of Application in Relation to Effluent
          Reduction Benefits                                        160

          Data Presentation                                         160

          Engineering Aspects of Control Technique Applications     154

          Process Changes                                           164

          Nonwater Quality Environmental Impact                     165

          EFFLUENT REDUCTION ATTAINABLE THROUGH THE APPLICATION
          OF THE BEST AVAILABLE TECHNOLOGY ECONOMICALLY
          ACHIEVABLE—EFFLUENT LIMITATIONS GUIDELINES               167

          Introduction                                              167

          Effluent Reduction Attainable Through Application  of
          the Best Available Technology Economically Achievable     153

          Identification of Best Available Technology
          Economically Achievable                                   172

          Rationale for Selection  of the Best Available
          Technology Economically  Achievable                        174

          Age of Equipment and Facilities                           175

          Total Cost of Application                                 175

          Engineering Aspects of Control Technique Application      175
                                  vni

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                             CONTENTS  (Continued)


Section
          Process  Changes                                           176

          Nonwater Quality Impact                                   17(>


XI.       NEW  SOURCE PERFORMANCE STANDARDS                          177

          Introduction                                              177

          Effluent Reduction Attainable  for New Sources            177

          Identification of New Source Control Technology          178

          Pretreatment Requirements                                 181

XII.      ACKNOWLEDGMENTS                                           182

XIII.     REFERENCES                                                183

XIV.      GLOSSARY                                                  189
                                  IX

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                             TABLES

Number

  1     Comparison of Production and Questionnaire
        Respondent Distribution Among Geographical
        Regions in the Country                                   9

  2     Federally Inspected Poultry Slaughter, Cut-Up, and
        Further Processed Volume, by Product Class, 1970        12

  3     Poultry:  Slaughtered under Federal Inspection,
        United States, by Classes, 1969-1971                    13

  4     Average Live and Eviscerated Weights by Type of Poultry 14

  5     Production of Broilers, Mature Chickens, and Turkeys,
        by Region, 1970                                         15

  6     Leading Ten states in Production of Broilers, Mature
        Chickens, and Turkeys, 1970                             16

  7     Civilian Per Capita Consumption  (Pound)                 18

  8     Production, Waste Water Flow, and Raw Waste Loading
        of Plants in Each Subcategory                           43

  9     Raw Waste Characteristics of Chicken Processors         48

 10     Raw Waste Characteristics of Turkey Processors          49

 11     Raw Waste Characteristics of Fowl Processors            51

 12     Raw Waste Characteristics of Duck Processors            52

 13     Raw Waste Characteristics of Further Processing Only    54

 14     The Number of Plants in the Questionnaire Sample
        Reporting the Use of Various Manufacturing Processes
        Within Each Sutcategory                                 57

 1UA    Effluent Quality from Conventional Filtration of
        Various Biologically Treated Wastewaters                112

 143    Performance of Microstrainers in Tertiary
        Treatment of Biologically Treated Wastewater            116

 14C    Selected Results for Nitrogen Control  in
        Effluents                                               120

 15     Typical Plant Operating Parameters Used for Estimating
        Cost of Meeting Effluent Limitations                    134

 16     Additional Investment Cost for "Typical" Plants in Each
        Subcategory to Implement Each Indicated Level of        135
                                 x

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                           TABLES (Continued)

Number                                                            FaSe
        Treatment, No Previous Expenditure  Included               135

 17     Addition to  the Total Annual Cost and Operating Cost
        for a Plant  in Each Subcategory  to  Operate Treatment
        System as Described                                       138

 18     Additions to the Annual Cost and Operating Cost Per
        Unit of Production for a Plant in Each  Subcategory
        to Operate Treatment System as Described                 139

 19     Waste Treatment Systems, Their Use  and  Effectiveness      141

 20     Industry Breakdown by Subcategory,  Size, and Type
        of Waste Treatment                                        142

 21     Waste Treatment System Configurations for Cost
        Effectiveness Curves                                      147

 22     Sludge Volume Generation by Waste Treatment  Systems       150

 23     Recommended  Effluent Limitations for July 1, 1977        155

 2U     Effluent Limitation Adjustment Factors  for Onsite
        Rendering and Further Processing                          156

 25     Waste Treatment Data for Exemplary  Chicken,  Turkey,
        and Duck Plants                                            161

 26     Recommended  Effluent Limitation  Guidelines  for
        July 1, 1983                                              169

 27     Effluent Limitation Adjustment Factors  for Onsite
        Rendering and Further Processing                          170

 28     Capital Investment, Operating and Total Annual Costs
        for New Point Sources                                      179

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                             FIGURES

Number                                                        Page

  I    General Process Flowsheet tor Poultry Processina        19

  2    General Process Flowsheet for Poultry Further
       Processing                                              20

  3    Categorization of Poultry Processing Industry           39

  4    Average Waste Water Volume Generated Per Bird in
       Processing Plants by Subcategory                        55

  5    Average Raw Waste Loading of Waste Water From Plants
       in Each Subcategory                                     56

  6    Product and Waste Water Flow for Typical Poultry
       Processing Plants                                       60

  7    Process and Waste Water Flow for Further Processing     61

  8    Approximate Relationship Between Raw Waste Loading of
       BOD5 and Waste Water Volume Per Bird for Chicken and
       Turkey Plants                                           63

  9    Suggested Poultry Processing Industry Waste Reduction
       Program                                                 84

 10    Dissolved Air Flotation                                 93

 11    Process Alternatives for Dissolved Air Flotation        94

 12    Activated Sludge Process                                103

 13    Chemical Precipitation                                  109

 HI    Sand Filter System                                      109

 15    Microscreen/Microstrainer                               114

 16    Nitrification/Denitrification                           118

 17    Ammonia Stripping                                       126

 18    Spray/Flood Irrigation System                           126

 19    Ion Exchange                                            130

 20    Waste Treatment Cost Effectiveness at Flow of 1.1U
       Million Liters/Day                                      114

 21    Waste Treatment Cost Effectiveness at Flow of 3 Million
       Liters/Day                                              145

                                 xii

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                            SECTION I

                           CONCLUSIONS
A  conclusion  of  this  study  is  that  the  poultry processing
industry comprises five sufacategories:

          Chicken processing
          Turkey processing
          Fowl processing
          Duck processing
          Further processing only

The primary criteria for establishing these categories were  type
of  raw  material,  i.e.,  kind of poultry, and raw waste load as
measured by 5-day biochemical oxygen demand (BOD5)  in  the  plant
waste  water.   The  type  of production process was an important
consideration in establishing a separate category for plants that
further process only.   Information  and  data  on  the  type  of
finished  product,  on  plant  parameters  such as size, age, and
location, and on other pollutants in  the  waste  water  and  the
treatability   of   those   wastes   all   support  the  industry
categorization.

The wastes from all  subcategories  are  amenable  to  biological
treatment  processes, and no materials harmful to municipal waste
treatment processes were found.

The 1977 discharge limits for BOD5, suspended solids, and  grease
are  based on actual performance data for waste treatment systems
in the poultry processing industry.  These limits are  being  met
by  plants  in  each  subcategory  having  onsite waste treatment
systems.  These limits plus a fecal coliform limit  are  proposed
for  1977,   The  same  limits  plus  a  limit  for  ammonia  are
recommended for new source limitations.  It is estimated that the
industry will have to invest about $14 million capital to achieve
the proposed 1977 limits.

For 1983, effluent limits were determined as the best  achievable
in  the  industry  for BODj>» suspended solids, Kjeldahl nitrogen,
ammonia, nitrites and nitrates, phosphorus, and  fecal  coliform.
The industry will have to invest about $39 million to achieve the
proposed   1983  limits.   The  latest  reported  annual  capital
expenditures by the industry are $60  million  for  each  of  the
three  years, 1970, 1971, and 1972.  It is further concluded that
where suitable and adequate land is available, land  disposal  by
irrigation  with no discharge may be a more economical option for
meeting the discharge limits, especially for small plants.

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                           SECTION II

                         RECOMMENDATIONS

Limitations recommendations for discharge to navigable waters  by
poultry  processing  plants  for  July  1, 1977, are based on the
performance of well-operated biological treatment plants  in  use
by  the industry.  The range in the limitations among the various
subcategories, in terms of live/weight killed (LWK)   or  finished
product (FP) as appropriate, are summarized below:

          BOD5:  0.39 to 0.77 kg/kkg LWK and 0.30 kg/kkg FP;

          Suspended Solids:  0.57 to 0.90 kg/kkg LWK and
                             0.35 kg/kkg FP;

          Grease:  0.14 to 0.25 kg/kkg LWK and 0.10 kg/kkg FP;

          Fecal Coliform:  400 counts/100 ml.

Adjustments  in  BOD5,  suspended solids, and grease are provided
for dressing plants that further process, and/or  render;  and  a
method  is explained for accounting for duck processors which may
discharge to a common sewer with a duck feedlot.

Recommended New  Source  standards  are  the  same  as  the  1977
limitations, with the addition of 0.14 to 0.26 kg ammonia per kkg
LWK and 0.1 kg ammonia per kkg FP.

Limitations  recommended  for  the  poultry industry for 1983 are
considerably more stringent and for BOD£, suspended  solids,  and
grease are based on the best performance of the treatment systems
and  in-plant  controls  now  in use in the poultry industry.  In
addition to limits on the  waste  parameters  included  in   1977,
limits are set for ammonia.  The discharge limits for ammonia are
set  at the concentration limits achievable by the best available
technology, rather than at a limit related to  production   level.
Adjustments  are  provided for BOD^, suspended solids, and  grease
for dressing plants that further process and/or render.

Duck plants with an onsite feedlot are subject  to  the  combined
processor regulation and 1983 feedlot regulations of no discharge
from the feedlot.  Thus the adjustment for processors is provided
for  only  that  portion  of  waste  load  due  t.o the processing
operation.

In cases where suitable and  adequate  land  is  available,  land
disposal by irrigation with no discharge may be a more economical
option  for  meeting  the  discharge limits, especially for  small
plants.

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                           SECTION III

                          INTRODUCTION
                      PURPOSE AND AUTHORITY
Section  301 (b)
Amendments  of
later than July
sources,  other
based  on  the
                 of  the  Federal  Water  Pollution  Control  Act
                1972   (the "Act") requires the achievement by not
                 1,  1977r  of  effluent  limitations  for  point
                 than  publicly-owned  treatment works, which are
                application  of  the  best  practicable   control
technology  currently  available  as defined by the Administrator
pursuant to Section 304 (b)  of  the  Act.   Section  301 (b)   also
requires  the  achievement  by  not  later  than July 1, 1983, of
effluent limitations for point sources, other than publicly-owned
treatment works, which are based on the application of  the  best
available technology economically achievable which will result in
reasonable   further   progress   toward  the  national  goal  of
eliminating the discharge of all  pollutants,  as  determined  in
accordance  with regulations issued by the Administrator pursuant
to Section 304(b) of the Act.  Section 306 of  the  Act  requires
the  achievement  by  new  sources  of  a  Federal  limitation of
performance  providing  for  the  control  of  the  discharge  of
pollutants   which  reflects  the  greatest  degree  of  effluent
reduction which th-a Administrator  determines  to  be  achievable
through  the  application  of  the  best  available  demonstrated
control  technology,  processes,  operating  methods,  or   other
alternatives,   including,   where   practicable,   a  limitation
permitting no discnarge of pollutants.

Section 304(b) of the Act requires the Administrator  to  publish
regulations providing guidelines for effluent limitations setting
forth  the  degree  of  effluent reduction attainable through the
application of the best practicable control technology  currently
available and the degree of effluent reduction attainable through
the  application  of  the  best  control  measures  and practices
achievable including treatment techniques, process and  procedure
innovations,  operation  methods  and  other  alternatives.   The
regulations  proposed  herein  set  forth  effluent    limitations
guidelines  pursuant to Section  304 (b) of the Act for the poultry
dressing and further processing industries subcategory within the
meat products source category.

Section 306 of the Act requires  the  Administrator,  within  one
year  after a category of sources is included in a list published
pursuant to Section  306(b)   (1)   (A)  of  the  Act,  to  propose
regulations  establishing  Federal  limitations of performance for
new sources within such categories.  The Administrator  published
in  the  Federal  Register  of January 16, 1973  (38 F.R. 1624),  a
list  of  27  source  categories.   Publication   of   the   list
constituted  announcement  of  the  Administrator's  intention of
establishing,  under  Section  306,  limitations  of   performance
applicable  to  new  sources  for   the  source category of  plants

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engaged in the dressing and further processing of poultry,
was included in the list published January 16, 1973.
which
     SUMMARY OF METHODS USED FOR.DEVELOPMENT OF THE EFFLUENT
       LIMITATIONS GUIDELINES AND STANDARDS OF PERFORMANCE

The   effluent   limitations   guidelines   and   limitations  of
performance proposed  herein  were  developed  in  the  following
manner.   The  point  source  category  was first studied for the
purpose  of  determining   whether   separate   limitations   and
limitations are appropriate for different segments within a point
source  category.   This  analysis  included  a  determination of
whether differences in animal type, raw  material  used,  product
produced,  manufacturing  process employed, equipment, age, size,
waste water constituents, and other factors  require  development
of  separate  effluent  limitations and limitations for different
segments  of  the  point  source   category.    The   raw   waste
characteristics  for  each  segment  were  then identified.  This
included an analysis of  (1) the source and volume of  water  used
in  the process employed and the source of waste and waste waters
in the plant; and  (2) the constituents (including thermal)  of all
waste waters, including toxic constituents and other constituents
which  produce  taste,  odor,  or  color  in  water  or   aquatic
organisms.   The  constituents  of  waste  waters which should be
subject to effluent limitations  guidelines  and  limitations  of
performance were identified (see Section VI).

The  full  range  of  control and treatment technologies existing
within the point source category was identified.   This  included
identification of each distinct control and treatment technology,
of  the  amount  of  constituents  (including  thermal),  and the
chemical, physical, and biological characteristics of pollutants,
and of the effluent level resulting from the application of  each
treatment  and  control  technology.   The required implementation
time was also  identified.   In  addition,  the  nonwater-quality
environmental  impact,  such as the effects of the application of
such technologies upon other pollution problems,  including  air,
solid  waste,  and  noise,  were  also  identified.   The  energy
requirements of each of the control  and  treatment  technologies
were  identified  as  well as the cost of the application of such
technologies.

The information, as outlined above, was then evaluated  in  order
to  determine  what  levels  of  technology constituted the "best
practicable  control  technology  currently   available,11   "best
available  technology  economically  achievable,"  and  the "best
available demonstrated control technology,  processes,  operating
methods,   or   other   alternatives."    In   identifying   such
technologies, various factors were  considered.   These  included
the  total  cost  of application of technology in relation to the
effluent quality achieved, equipment and facilities involved, the
process employed, the engineering aspects of the  application  of
various  types  of control techniques, process changes, nonwater-
quality environmental impact (including energy requirements), and

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other factors.  Once the alternative wastewater treatment systems
corresponding to the three levels of technology  described  above
had  been  determined, limitations on the discharge of pollutants
attainable by the  technology  appropriate  to  each  level  were
established.   The  nature  and extent of data available for each
subcategory determined the precise method by which  the  ettluent
limits were developed.

To  the  extent possible, the limitations for BPCTCA were derived
as averages of  the  actual  effluent  discharge  from  the  best
treatment  systems  identified in the subcategory.  In some cases
it was not possible to employ this methodology because of limited
data on the performance of treatment systems  in  a  subcategory.
In  these  instances,  limits  were  based  on the performance of
whatever plants in the category could  be  considered  exemplary.
In  cases  where  there  were  few  such plants, limits were then
verified by comparison with  known  pollutant  concentrations  in
effluent  from  plants  in  these categories  (or other categories
with similar wastes and treatment  facilities)  and  the  average
flow  for  plants  within the category.  Where effluent data were
not available at "all, the effluent limits  were  derived  in  the
first  instance  by means of this procedure.  Multiple regression
analyses were  also  used  to  verify  the  relationship  between
limitations on different pollutant parameters.

The  data  for  identification  and  analysis were derived from a
number of sources.  These  sources  included  Refuse  Act  Permit
Program data; EPA research information; data and information from
North  Star  files  and reports; a voluntary questionnaire issued
through   the   National   Broiler   Council,   Poultry   Science
Association,  Poultry  and Egg Institute of America, Southeastern
Poultry and  Egg  Association,  Poultry  Industry  Manufacturer's
Council, Arkansas Poultry Federation, National Turkey Federation,
Pacific  Egg  and  Poultry  Processors  Association,  Mississippi
Poultry Improvement Association,  and  Alabama  Poultry  and  Egg
Association;   and    onsite  visits  and  interviews  at  several
exemplary poultry processing  plants  in  various  areas  of  the
United  States,  All  references used in developing the guidelines
for effluent limitations and limitations of performance  for  new
sources  reported  herein  are  included  in  Section XIII of this
document.

The data base was primarily comprised of data from questionnaires
and  plant  waste  water  sampling.   It  included  152   poultry
processing  plants.   There  were 92 questionnaire responses from
chicken  processing   plants.   Based  on  the  number  of   birds
reportedly  slaughtered  by  each plant per day, these 92 chicken
processing plants account for  about  63  percent  of  the  total
number  of  chickens  slaughtered  by Federally inspected plants.
There were  34  questionnaire  responses  from  turkey  processing
plants.   These  34   plants slaughter approximately 61 percent of
the total  number  of  turkeys  slaughtered.   There  were  seven
questionnaire  responses  from  fowl  processing plants  and these
seven plants  slaughter 37 percent of the  total  number  of  fowl
slaughtered.   The  five  duck  processing  plants  that returned

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questionnaires account for 51 percent of the  duck  slaughter  by
number.   There  were  five  further  processing only plants that
returned questionnaires.

Questionnaires were also received from nine plants that slaughter
more than one category of bird or  that  process  other  poultry.
The  plants  include  the  following:   one plant that slaughters
chickens and turkeys; one plant that slaughters geese, ducks, and
capons; one plant that  slaughters  and  processes  ducks,  fowl,
broilers,  and  turkeys;  one  plant that slaughters chickens and
Cornish hens (very young chickens, about 5 weeks old); one  plant
that  slaughters  Cornish  hens  only;  one plant that slaughters
squab; one plant that slaughters ducks  and  turkeys;  one  plant
that  cuts  and  packages fresh poultry; and two rabbit slaughter
plants,                             i

The geographical distribution of the  plants  responding  to  the
questionnaire  is  shown  in  Table  1.  As can be seen, the live
weight  production  distribution  and  the  distribution  of  the
questionnaire  respondents  among  the regions of the country are
very similar.

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                           Table  1.   Comparison of  Production  and  Questionnaire  Respondent
                                      Distribution among Geographic Regions  in  the  Country*
Region**
North Atlantic
North Central
South Atlantic
South Central
West
Total
Broilers
Production
5.5%
2.9
41.9
44.9
4.8
100.0%
Ques t ionnair es
3.3%
1.1
43.5
48.8
3.3
100.0%
Fowl
Production
14.0%
25.6
23.4
24.7
12.3
100.0%
Questionnaires
0%
28.6
28.6
28.6
14.2
100.0%
Turkeys
Production
2.7%
41.8
17.1
15.7
22.7
100.0%
Questionnaires
2.9%
47.1
11.8
8.8
29.4
100.0%
V0
        *Note:  Production figures reported in more detail  in Figure  3.

       **STATES IN POULTRY REGIONS
North Atlantic
Maine
New Hampshire
Vermont
Massachusetts
Rhode Island
Connecticut
New York
New Jersey
Pennsylvania

North Central
Ohio
Indiana
Illinois
Michigan
Wisconsin
Minnesota
Iowa
Missouri
Nebraska
Kansas
South Atlantic
Delaware
Maryland
Virginia
West Virginia
North Carolina
South Carolina
Georgia
Florida


South Central
Kentucky
Tennessee
Alabama
Mississippi
Arkansas
Louisiana
Oklahoma
Texas


West
Idaho
Colorado
Arizona
Utah
Washington
Oregon
California




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               GENERAL DESCRIPTION OF THE INDUSTRY

The poultry processing industry falls within SIC Code 2016, which
includes young and mature chickens, turkeys,  and  other  poultry
slaughtering, dressing (evisceration), and ice or freeze packing,
and  that  part of SIC Code 2017 dealing only with poultry (e.g.,
chicken  and  other  poultry  canning  and  freezing  or  related
processing   into   specialty  items).   Young  chickens  include
broilers-fryers and other young immature birds such  as  roasters
and  capons; mature chickens are fowl from breeder and market egg
flocks and stags and cocks; turkeys include fryer-roasters, which
are young immature birds, usually under 16 weeks  of  age,  young
turkeys  grown to a mature market age, usually 5 to 7 months, and
old  turkeys  which  are  fully  matured  birds  held   for   egg
production, usually over 15 months of age; other poultry includes
ducks, geese, guineas, squabs, pigeons, partridge, pheasants, and
rabbits  and  small  game.   Excluded  from this study were those
portions of SIC 2017  dealing  with  egg  processing  and  plants
manufacturing such products as canned soups and TV dinners.

Plants   within   the   industry  carry  out  the  operations  of
slaughtering,  dressing,  and  further  processing  of  broilers,
chickens,  fowl  (mature  chickens), turkeys, ducks, geese, other
birds, and rabbits  and  other  small  game.   Some  plants  only
slaughter  and  dress  (eviscerate),  others slaughter, dress and
further  process;  and  still  others   further   process   only.
Occasionally,  poultry  slaughterhouses have rendering operations
on the same site but housed separately.

The products of  slaughtering  and  eviscerating  operations  are
icepacked  or  chilled ready-to-cook broilers and chickens, fresh
or frozen  fowl,  turkeys,  etc.   Further  processing  following
slaughter and dressing operations converts poultry into a variety
of  cooked, canned, and processed poultry meat items such as pre-
cooked breaded parts, roasts,  rolls,  patties,  meat  slices  in
gravy, canned boned chicken, and various sausages.  The amount of
further  processing  performed  in poultry slaughterhouses varies
considerably.  Some plants may process only a part of their  kill
while  others  may  process  their own kill plus birds from other
plants.  Most of the further  processing  in  slaughterhouses  is
limited   to  cutting,  cooking,  batter  coating  and  breading,
browning, and  freezing.   The  type  and  number  of  operations
carried   out   in   plants   that   further  process  only  vary
considerably, resulting in a wide variety of  finished  products.
The  usual  practice in turkey plants is to slaughter only during
seven to nine months of the year.   If  the  plant  also  further
processes,  it will usually produce processed products during the
entire year.

The poultry industry is typified  by  vertical  integration  from
hatchery   through   feed  mill,  slaughtering,  processing,  arid
wholesale  marketing  under  contract.   The   slaughtering   and
processing  plants  are  therefore  integral  parts  of  a larger
system.  For example, the typical integrated broiler firm has its
                                 10

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own hatchery, feed mill, and processing plant,  and depends almost
entirely on contract  production.    The  firm  may  be  local,   a
subsidiary  of  a national feed company or meat packer, or a part
of a  large  conglomerate.   Turkey  and  duck  slaughtering  and
processing  firms tend to follow a similar pattern; however, fowl
or mature chickens tend to  be  a  byproduct  of  commercial  egg
production.   The  vast  majority  of  poultry  production  is in
broilers, turkeys and mature chickens (fowl).  This can  be  seen
in  Table  2  which  shows  the  weights  by  class  in  1970 for
slaughtered, cut-up, and further processed poultry  in  Federally
inspected  plants.   Young  chickens (which include broilers) and
all turkeys accounted for 93  percent  of  the  total  slaughter.
Young  chickens accounted for over 90 percent of the total cut-up
volume;  while  turkeys,  mature  chickens,  and  young  chickens
accounted  for  over  93  percent  of the total further processed
volume.  In 1970, plants  under  Federal  inspection  slaughtered
over 90 percent of the total U. S.  production of young chickens,
mature chickens and turkeys.

Table  3  shows  the  numbers  and  pounds   (both live weight and
eviscerated  or  ready-to-cook  weight)  of  Federally  inspected
poultry by class for 1969 through 1971.  From the data in Table 3
on  pounds  slaughtered by type of bird, the average live weight,
eviscerated weight, and yield  were  calculated  for  each  type.
These are given in Table 4.

In  1973,  according  to  the  USDA,  there  were  248  Federally
inspected poultry plants that slaughter only,  288  that  process
only,  and  144  that  slaughter  and  process.2   However, it is
believed that a majority of the 288 process-only  plants  produce
products  such  as  canned  soups and TV dinners or are otherwise
excluded from this  point  source  category.   These  plants,  as
previously  mentioned,  do  not  fall  within  the  scope of this
program and will not be considered in this report.   Also  plants
handling both poultry and red meat are excluded.

Poultry  is  produced in nearly every State of the United States.
However the largest production of broilers and turkeys is  highly
concentrated by geographic area.  Furthermore, poultry production
(hatching  and  growing) is carried out within close proximity to
slaughtering  and  dressing  Operations.   Table  5   shows   the
production of broilers, mature chickens and turkeys by region for
1970.  This table shows that the South Atlantic and South Central
regions  account for 86.8 percent of the broiler production; 48.1
percent of the mature chicken production, and, 32.8 percent of the
turkey production.  Table 6 shows the production in  live  weight
for  broilers,  mature  chickens, and turkeys for the leading ten
States in 1970.  The top ten States in broiler production,  which
are  mainly  from  the  South Atlantic and South Central regions,
account for 84 percent of the total U. S.  production.   The  top
ten  States in turkey production produced 75 percent of the U. S.
turkey output in 1970.  However,  turkey  production  is  not  as
highly  concentrated  regionally  as broiler production, with the
two largest regions—West North Central and West—accounting  for
52  percent  of the U. S. production in 1970.  Production of fowl


                                 11

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                    Table 2.   Federally Inspected  Poultry Slaughter,  Cut-up,  and
                              Further Processed Volume,  by Product  Class,  1970
Category
Slaughtered (1,000 pounds live weight)
Percentage of total slaughter
Cut-up (1,000 pounds ready-to-cook)
Percentage of total cut-up
Further processed (1,000 pounds ready-
to-cook)
Percentage of total further processed
Young
Chickens
*
10,073,725
77.7
1,842,594
90.2
337,292
26.2
Mature
Chickens
**
810,555
6.3
8,608
0.4
392,404
30 . 3
Turkeys
t
1,987,715
15.3
190,713
9.3
479,427
37.1
Other
Poultry
ft
81,860
0.7
2,230
0.1
83,274
6.4
Total
Poultry
12,953,825
100.0
2,044,145
100.0
1,292,397
100.0,
 *Young chickens are commercially grown broilers-fryers and other young  immature birds  such as
  roasters and capons.
**Mature chickens are fowl from breeder and market egg flocks and stags  and cocks.
 tlncludes fryer-roasters which are young immature birds,  usually under  16 weeks of age;  young
  turkeys grown to a matured market age, usually 5 to 7 months;  and old  turkeys which are fully
  matured birds held for egg production, usually over 15 months  of age.
ttlncludes ducks, geese, guineas, squabs, pigeons, partridge, pheasants,  and rabbits.
Source:  Based on data from Slaughter Under Federal Inspection and Poultry Used  in Further
         Processing, SRS-USDA, Pou 2-1(2-71).

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                               Table 3.   Poultry:   Slaughtered under Federal Inspection,
                                         United States, by Classes, 1969-19713

Class

Young chickens
Mature chickens
Total chickens
Young turkeys
Old turkeys
Fryer-roaster turkeys
Total turkeys
Ducks
Other poultry
Total poultry

Class

Young chickens
Mature chickens
Total chickens
Young turkeys
Old turkeys
Fryer-roaster turkeys
Total turkeys
Ducks
Other poultry
Total poultry
Number Inspected
1969
Thousands
2,516,287
153,767
2,670,054
84,476
1,245
9,651
95,372
11,589


1970
Thousands
2,770,178
176,116
2,946,294
92,990
1,058
11,501
105,549
11,883


1971
Thousands
2,778,971
183,194
2,962,165
98,226
1,199
12,319
111,744
11,030


Pounds Certified (Ready-to-Cook)
1969
Thousands
6,484,117
454,400
6,938,517
1,344,352
18,886
69,548
1,432,786
51,133
4,438
8,426,874
1970
Thousands
7,161,141
516,336
7,677,477
1,468,038
16,315
82,157
1,566,510
52,617
5,023
9,301,627
1971
Thousands
7,281.021
523,884
7,804,905
1,536,241
18,353
87,018
1,641,612
49,413
6,147
9,502,077
Pounds Inspected (Liv.e Weight)
1969
Thousands
9,064,962
710,935
9,775,897
1,693,643
23,881
89,618
1,807,142
72,018
6,898
11,661,955
1970
Thousands
10,073,724
810,554
10,884,278
1,860,995
20,667
106,053
1,987,715
74,042
7,789
12,953,824
1971
Thousands
10,223,510
825,265
11,048,775
1,949,966
23,496
112,588
2,086,050
69,341
9,526
13,213,692













u>

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Table 4.  Average Live and Eviscerated Weights by Type of Poultry
Class
Young chickens
Mature chickens
Young turkeys
Old turkeys
Eryer^roast-er- turkey...
Ducks
Live Weight
kg, (pounds)
1.7 (3-7)
2.1 (4.6)
9.1 (20.0)
8.8 (19.4)
4.2. (9.2.>
2.8 (6.2)
Eviscerated Weight,
kg, (pounds)
1.2 (2.6)
1.3 (2.9)
7.2 (15.8)
6.9 (15.3)
3.2 (7.X)
2.0 (4.4)
Yield,
percent
70.0
63.0
79.2
79.0
77.2
71.0

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        Table 5.  Production of Broilers, Mature Chickens,
                  and Turkeys, by Region,.1970l
Region*
North Atlantic
East North Central
West North Central
South Atlantic
South Central
West
United States (48)
Broilers
594,356
(5-5)**
155,086
(1.4)
161,984
(1.5)
4,528,245
(41.9)
4,855,432
(44.9)
506,740
(4.8)
10,801,843
(100.0)
Mature
Chickens
167,156
(14.0)
145,191
(12.1)
160,664
(13.5)
278,502
(23.4)
295,965
(24.7)
147,457
(12.3)
1,194,935
(100.0)
Turkeys
59,828
(2.7)
273,188
(12.5)
638,712
(29.3)
372,638
(17.1)
341,901
(15.7)
498,186
(22.7)
2,184,453
(100.0)
   STATES IN POULTRY REGIONS
North Atlantic
Maine
New Hampshire
Vermont
Massachusetts
Rhode Island
Connecticut
New York
New Jersey
Pennsylvania
South Atlantic
Delaware
Maryland
Virginia
West Virginia
North Carolina
South Carolina
Georgia
Florida
Western
Idaho
Colorado
Arizona
Utah
Washington
Oregon
California


South Central
Kentucky
Tennessee
Alabama
Mississippi
Arkansas
Louisiana
Oklahoma
Texas
East North Central
Ohio
Indiana
Illinois
Michigan
Wisconsin




West North Central
Minnesota
Iowa
Missouri
Nebraska
Kansas



** Numbers in parentheses  are regional  shares  of United States total
                             15

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                      Table 6.   Leading Ten States in Production of Broilers,
                                Mature Chickens,  and Turkeys,  1970 ^
Broilers
State

Georgia
Arkansas
Alabama
North Carolina
Mississippi
Maryland
Texas
Delaware
California
Maine
Total
Production
(Live Weight)
1000 Pounds
1,577,149
1,539,126
1,313,981
1,137,295
892,660
722,452
662,591
521,535
338,922
321,510
9,027,221
Mature Chickens
State

California
Georgia
Arkansas
North Carolina
Pennsylvania
Alabama
Mississippi
Texas .
Florida
Indiana
Total
Production
(Live Weight)
1000 Pounds
102,824
100,546
84,582
72,026
63,558
61,265
51,006
46,037
44,144
42,441
668,429
Turkeys
State

California
Minnesota
North Carolina
Texas
Missouri
Arkansas
Iowa
Indiana
Utah
Virginia
Total
Production
(Live Weight)
1000 Pounds
302,834
302,677
175,959
169,150
158,979
143,081
122,015
93,374
85,294
77,451
1,630,814
Source:  Based on data from Statistical Reporting Service,  USDA.

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or mature chickens is less concentrated regionally than  is  that
for either broilers or turkeys, with the top ten States producing
only 56 percent of the U. S. production in 1970,  Again the South
Atlantic  and  South  Central  regions are the largest regions in
mature chicken production,  accounting  for  48  percent  of  the
total.

Production  of  other  poultry  (and  small game), such as geese,
ducks, rabbits, squabs, pigeons, partridge, pheasants and guineas
appears to be regionally concentrated.  Geese production  appears
to  be  mainly  in  Minnesota  and  the Dakotas; duck production,
mainly on Long Island, New York,  and  around  Lake  Michigan  in
Indiana  and  Wisconsin;  and  rabbit  production in Arkansas and
Kansas.  Other poultry accounts for  only  0.7  percent  by  live
weight  of  the  total poultry processed  (see Table 2), and ducks
account for about 90 percent of that  (see Table 3).

The volume of all  poultry  slaughtered  in  Federally  inspected
poultry  plants  increased  from  8.1 to 13.2 billion pounds live
weight between 1961 and 1971—a 62 percent increase.  In the same
period, the number of slaughtering plants decreased from  532  to
about  400.   Civilian per capita consumption of poultry has also
increased dramatically over the  years,  as  shown  in  Table  7.
Chicken  per  capita consumption, for example, has increased from
20.6 to 30.0 to 41.4 pounds for the years 1950, 1961,  and  1971,
respectively.   In  fact.  Table 7 shows that the combined turkey
and chicken consumption has increased more rapidly over the years
1950 to 1972 than that for all red meats.

Most poultry processing plants  are   located  in  or  near  urban
areas,  primarily  small towns, where labor and water are readily
available.   Poultry  processing  plants—both  slaughtering  and
further   processing   are   labor    intensive  operations.   The
slaughtering or dressing plants,  as  mentioned  previously,  are
located near poultry production areas.  However, plants that only
further  process  poultry  may  be located outside the production
areas.
                   GENERAL PROCESS  DESCRIPTION

A general process flowsheet of a typical  poultry  slaughterhouse
is  shown  in  Figure  1;  that  for further  processing  of poultry is
shown  in Figure  2.  The  processing  steps  included  in  Figures   1
and  2 are not  intended to be all-inclusive but to  represent the
typical plant.   For example,  duck slaughtering  includes  a wax dip
operation not  shown in Figure 1.  In  addition,  some  operations
depicted  in   Figure  2 may not be used  in some  plants, while some
other, less frequently used,  processes  are not  included  in Figure
2.   Specific  plant  processes  may  also  differ   in   order  or
arrangement  from  that   shown in Figure  2 for  further processing
plants.

Some poultry plants that slaughter  may  also  further  process.
However,  the  information gathered during this study showed that
                                 17

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                                     Table 7.  Civilian Per Capita Consumption  (Pound)4
oc

1950
1955
1956
1957
1958
1959
1960
1961
1962
1963
1964
1965
1966
1967
1968
' 1969
1970
1971
1972*
i
'
Eggs
(No.)
389
371
369
362
354
352
335
329
327
318
318
3.14
313
320
316
310
311
314
307
Chickens
and
Turkeys
24.7
26.3
29.6
31.4
34.0
35.2
34.2
37.4
37.0
37.5
38.5
40.9
43.9
45.8
45.4
47.4
49.7
49.9
52.0
All
Chickens
20.6
21.3
24.4
25.5
28.1
28.9
28.1
30.0
30.0
30.7
31.1
33.4
36.1
37.2
37.4
39.1
41.5
41.4
42.9
Broilers
Only
8.7
13.8
17.3
19.1
22.0
22.8
23.4
25.8
25.7
27. Q
27.6
29.4
32.3
32.8
33.1
35.2
37.4
37.1
38.8
Turkeys
4.1
5.0
5.2
5.9
5.9
6.3
6.1
7.4
7.0
6.8
7.4
7.5
7.8
8.6
8.0
8.3
8.2
8.5
9.1
All
Red
Meats
145
163
167
159
152
160
161
160
163
170
175
167
171
178
183
182
186
192
189
Beef
and
Veal
71.4
91.4
94.9
93.4
87.2
87.1
91.2
93.4
94.4
99.4
105.1
104.7
108.8
110.3
113.3
114.1
116.6
115.7
118.2
Pork
69.2
66.8
67.3
61.1
60.2
67.6
64.9
62.0
63.5
65.4
65.4
58.7
58.1
64.1
66.2
65.0
66.4
73.0
67.4
Lamb
and
Mutton
4.0
4.6
4.5
4.2
4.2
4.8
4.8
5.1
5.2
4.9
4.2
3.7
4.0
3.9
3.7
3.4
3.3
3.1
3.3
             *Preliminary

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      WEIGHING,
       GRADING
    AND PACKAGING
                 SHIPPING
Figure 1.  General Process Flowsheet  For
           Poultry Processing
              19

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POULTRY
CARCASSES
RECEIVING
  AND
STORAGE
                            FINAL
                           PRODUCT
                         PREPARATION
      Figure  2.   General Process  Flowsheet For
                  Poultry Further  Processing
                     20

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in  the  majority  of  the  plants  that  do  both,   the  further
processing  operations  usually  involved cut-up,  cooking, batter
and breadinqr deep frying, and freezing.  The specialty products,
such as  rolls,  luncheon  meats,  patties,   etc.,  are  produced
primarily  in  further  processing  only  plants,   A few of these
plants—usually turkey plants—may slaughter  during  a  specific
time  of  the year and further process for part or for the entire
year.   The  dressed  birds  can  be  frozen  readily  for  later
processing.   Most  specialty  products  are produced for hotels,
restaurants, institutions, and fast-food outlets.
The major  limitation  manufacturing  processes  in  most  modern
poultry  slaughtering or dressing plants—are receiving, killing,
bleeding,  defeathering,  eviscerating,  chilling,  and   packing
(Figure 1).  Associated with these processes are the subprocesses
of materials recovery and plant cleanup.

Most  plants  have "flow-away" systems for feathers and offal; in
these systems water in flumes is used to carry away the  feathers
and  offal,  separately,  to byproduct recovery,  A few plants do
not have flow-away systems for  feather  and/or  offal  handling.
Kosher  processing  of poultry, for example, involves dry picking
and collecting of feathers.  Other plants have replaced  the  wet
offal  flow-away system with dry evisceration and offal handling.
This is to reduce water use and waste load.  Rabbit dressing,  of
course,  includes  skinning for pelt removal rather than scalding
and defeathering.


                            Receiving

Live birds are trucked to poultry processing plants in  coops  on
open  trucks.   The  coops  hold  up  to  about  20  broiler-size
chickens.  Normally, the trucking of birds to plants is scheduled
so that, the birds are held in the receiving area  for  a  minimum
amount  of time.  Holding the birds too long results in increased
incidences of death and loss of birds.  The greater  the  holding
time,  also,  the greater the pollution load in the receiving and
holding area for manure.

Coops containing the  chickens  are  usually  unloaded  from  the
trucks  onto  a conveyor system.  The birds are then conveyed, in
the coops, to a hanging area where the birds are removed from the
coops and attached by their feet to shackles  suspended  from  an
overhead  conveyor  line.   Occasionally  coops  are  permanently
attached to the trucks; the birds  then  are  hung  as  they  are
removed  from  the  coops.   The  conveyor system, traveling at a
constant speed, now carries the shackled birds into  the  killing
area.   Empty  coops  are  returned  to  the  trucks by conveyor,
normally without being cleaned.  One or more  overhead  conveying
systems  may  be  used in the receiving area or in the processing


                                 21

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area, depending on the size of the plant, the plant  layout,  and
the number of birds to be killed that particular day.

Manure,   feathers,  and  dirt  are  the  major  pollutants  that
accumulate on the floor of the receiving area.  When live poultry
are held for  a  relatively  short  time  in  a  receiving  area,
quantities of pollutants, except nitrogenous nutrients, are minor
compared  to  pollutants from other processes.  However, extended
holding of poultry can add significant quantities of  pollutants.
Forges5  reported that the waste from the storage of chickens was
32 pounds of BODj> and 35 pounds of suspended solids per  thousand
chickens  stored  each  day;  Porges  and Struzeski6 reported the
values as 36 and 40 pounds, respectively.  Forges5 also  reported
that  the  amount  of BODji to the sewer is reduced to 5.0 pounds,
and the suspended solids to 6.0 pounds per thousand birds  stored
daily,  if dry cleanup is practiced in the receiving area.  Waste
materials collected by dry  cleaning  are  dumped  as  refuse  or
loaded  onto  the offal truck along with the feathers, offal, and
blood, and sent to rendering.   Relatively  small  quantities  of
water  are  used  in  this area, following dry cleanup, to remove
residual material.
                      Killing and Bleeding

In  most  modern  plants,  birds  are  shocked  just  before   or
immediately    following    killing  . to   facilitate   bleeding.
Slaughtering of poultry is done by either  severing  the  jugular
vein or by debraining.  Manual and automatic mechanical severance
of  the  jugular  vein  are  the common killing techniques in use
today.  The killing area is usually a  we11-contained  area  with
high  walls  on  both  sides of the conveyor line to restrict the'
drainable blood to this area.  Such an arrangement  is  called  a
"blood  tunnel."   Data  collected show that chickens are held in
the tunnel from 45 to 125 seconds for draining the blood, with an
average time of 80 seconds; turkeys from 90 to 210  seconds  with
an average time of 131 seconds.

Most  poultry processing plants attempt to recover as much of the
free-draining blood as they can.  Even under the best  conditions
and  with  adequate drainage time—say two minutes—only about 70
percent of the blood in poultry is recovered in the killing area.
The blood is usually permitted to congeal on  the  killing  floor
and is removed, as a semisolid, from once to several times a day,
depending  on  the cleanup procedures in the plant.  A few plants
have recently installed troughs just below the bleeding birds  to
collect blood.  The blood is periodically removed from the trough
by vacuum, pump, or gravity flow.  The blood trough should reduce
the waste load due to blood losses to the sewer.

Feathers,  dirt,  manure,  and blood are pollutants that may find
their way into the sewer from  the  killing  area;  that  of  the
greatest  significance is, of course, blood.  Congealed blood and
other pollutants too difficult to  remove  by  draining  and  dry
scraping are flushed to the sewer during cleanup.


                                 22

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Blood that is collected in the killing area is usually mixed with
the  feathers  on  the offal truck.   A less common blood handling
process, but one that appears to be increasing  in  use  involves
loading  the  blood into receiving tanks that are attached to, or
part of, the offal truck.  Obviously, the  storage  of  blood  in
tanks  is  preferable, since blood dumped onto the feathers in an
offal truck can drain from the truck and into a  sewer.   If  the
plant  has  onsite  rendering,  feathers and blood are frequently
handled separately to give higher quality rendered products.


                          Defeathering

After killing, the birds are scalded in either a scald tank or  a
spray  scald.   Tank  scalding  is  by  far the most common.  The
scalding of the bird helps to relax feather follicles for  easier
feather  removal.  Water temperature in a scald tank was found in
this study to be between 51° and 60°C {124° and  140°F)  with  an
average  of 53.3°C (128°F)  for chickens, and between 52° and 63°C
(135° and 145°F) with an average of 59.5°C  (139°F) for turkeys.

The feathers are removed mechanically  after  scalding.   Usually
defeathering  is  accomplished  by continuously passing the birds
through  machines  equipped  with  rubber  fingers  attached   to
rotating  drums;  the  fingers  flail  the  birds,  removing  the
feathers.  Simultaneously with the feather removal, warm water is
sprayed onto the birds as a lubricant, and to flush away feathers
as they are removed.  In a few cases, mainly  small  or  seasonal
operations,  batch-type  defeathering  machines  are  used.  This
requires that the birds be removed from the shackles,  placed  in
the  machine, defeathered, and then replaced on the conveyor line
by hand.  This  type  of  defeathering  obviously  requires  more
labor.   The  number  and kind of defeathering machines used in a
plant depends on the type and size of the birds  to  be  cleaned.
Feathers are usually conveyed from the defeathering area by water
in a flow-away system.

Following  defeathering,  the  remaining pinfeathers are removed,
usually by hand.  In duck processing plants, the pinfeathers  are
removed  by wax stripping.  In this process, the birds are dipped
into molten wax and cooled with a spray of water  to  harden  the
wax.   Stripping  away  the hardened wax removes the pinfeathers.
The wax is reclaimed and reused.  After defeathering,  all  birds
while on the conveyor are passed through a gas flame to singe the
remaining  fine  hairs  and  pinfeathers, washed, and transported
into the evisceration area.

Waste water from the defeathering  operations  results  from  the
following: continuous overflow from the scald tank; final dump of
the scald tank at the end of the operating day; feather flow-away
system;  continuous  water  spray  in  the defeathering machines;
carcass washing; and washdown of the floors and equipment  during
cleanup.   The  minimum  overflow  from the scald tank is about 1
liter (1/4 gallon) per bird.
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;-'eathers removed by the defeathering machines and flumed away  in
the  flow-away  system  contain  manure,  dirt, and blood.   These
materials may be dissolved or  suspended  in  the  waste  waters,
thereby  contributing  to  the  waste  load from the defeathering
area.  Feathers themselves should not contribute significantly to
the waste load because they can be easily removed from the  water
by  screening.   Presently, considerable attention is being given
to the capture of feathers, since feathers escaping  into  sewers
are a major nuisance in sewage treatment.


                          Evisceration

The  evisceration  room is segregated from the killing, bleeding,
scalding, and defeathering areas of  the  plant  to  insure  that
eviscerated birds are not exposed to cross-contamination from any
of  the  previous  operations.   Washing,  chilling, packing, and
cutting of the eviscerated birds are  carried  out  in  the  same
general plant area as evisceration,

When  the  birds  enter  the  eviscerating  area,  their feet are
removed, usually with an automatic cutter.  The feet  are  either
dry collected or flumed, usually in the feather flow-away system.
The  birds  are  then  re hung  on  a  different  conveyor line to
facilitate removal of the viscera and inspection.

On  the  evisceration  line,  the  oil  gland  is  removed;   the
peritoneal  cavity  is  opened,  the  viscera  are pulled out and
exposed, and the carcass and entrails are inspected; the  giblets
are  recovered,  trimmed,  and  washed;  the inedible viscera are
discharged., usually to the offal flow-away system; the lungs  are
removed  by  vacuum, raking, or by hand; the head is removed; and
finally, the neck is removed and washed.  Cleaning of the gizzard
involves splitting, washing out the contents, peeling  the  inner
liner, and a final wash.  The giblets  (heart, liver, and gizzard)
are  conveyed  to  giblet  chillers.  The inedible viscera may be
carried away by vacuum or mechanical conveying rather than  by   a
flow-away  system  if  dry evisceration is used.  The eviscerated
birds  are  thoroughly  washed,  both  inside  and  outside,  and
conveyed to chillers.

Potential  pollutants from the evisceration process include feet,
heads, viscera, crop, windpipes, lungs, grit,  sand  and  gravel,
flesh, fat, grease, and blood.  Usually these are received by the
offal  flow-away system which carries them to the screening room.
The  screening  removes  the  bulk  of  the  suspended  material;
however,  some  soluble  organic  matter, blood, grit, sand, fat,
grease, and flesh particles are not removed.  The BOD5  level  of
the  waste  water  in  this  stream  is only a few hundred mg per
liter, but the flow per thousand birds is so high that the  total
BOD_5  load  from the evisceration process is higher than from any
other process.  It is not uncommon for  evisceration  to  account
for  40 to 50 percent of the BOD5 load in the plant effluent.


                                24

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The  major  sources  of water from evisceration are the flow-away
water,  water  from  the  many  hand  washers  located   on   the
eviscerating  trough,  from  the washers in the automatic gizzard
splitters, and from carcass washers.

                     Chilling and Packaging

Before the birds  can  be  packed  for  shipment,  they  must  be
chilled.   Removal  of  the  body  heat is an important operation
because rapid cooling protects the meat flavor  and  quality  and
lengthens  the market life by preventing bacterial decomposition.
Almost  all  modern  poultry  processing  plants  rely  on  large
chilling  tanks  containing ice water.  Several forms of chilling
tanks are in operation.  One  is  a  large  enclosed  drum  which
rotates  about  a  central axis; another is a perforated cylinder
mounted within a chilling vat; and still another type is a  large
open  chilling  tank  containing  a  mechanical rocker to provide
agitation.  In all of these, birds cascade forward with the  flow
of water.

Most  poultry  plants  use  several  chilling  tanks  in  series,
typically two or three.   The  flow,  while  carrying  the  birds
through  the  individual  tanks,  is  c cunte re ur rent  through the
series so the first chilling tank that the birds enter is  warmer
than  the  next,  and  so  on.   In  this  arrangement,  ice  and
freshwater are added to the last chiller.  The USDA requires one-
half gallon per bird overflow in the chillers; the flow typically
is about three-fourths of a gallon per bird.  The  effluent  from
the  first  chiller  is  occasionally used in the offal flow-away
system.  Normally the carcass of the bird is chilled within 30 to
40 minutes to an ultimate carcass temperature of 1°C
A similar, but separate and smaller, chilling system is used  for
cooling giblets.

After  the  birds are chilled, they are rehung on a conveyor line
to allow the excess moisture to drain off.  The  birds  are  then
conveyed  to  an  automatic weighing and separating area, and are
graded and packed or are routed to further processing.

Old and small plants,  which  do  not  use  continuous  flow  and
chilling,  cool the carcasses in batch tubs of ice and water with
bubblers for mixing.   Cooled  birds  are  then  drained,  sized,
graded, and packaged manually.

The  majority  of broilers are ice-packed or packed with dry ice.
Turkeys,  ducks  and  exotic  fowl  are  usually  frozen;  mature
chickens,   which   are   used  almost  exclusively  for  further
processing, are sold either ice-packed or  frozen.   Freezing  of
poultry  produces  no  inherent waste water; ice-packing has very
little effect on waste water.
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                         Sutaprocesses

By-Product Recovery

The major byproducts  of  poultry  slaughtering—blood,  feathers
(skins) ff and offal—are recovered by nearly all plants.  However,
grease  recovery  is  not  as  effectively  practiced  by poultry
slaughtering plants as  by  meat  packing  plants,,   Fortunately,
however,  grease  loads  in  poultry  plants  are  not  as great.
Wasting byproducts not only increases the  waste  load  in  plant
effluents,  and hence treatment costs, but also wastes a valuable
raw material used  by  rendering  plants  in  the  production  of
proteinaceous  animal  feeds.   Small amounts of small game skins
and feathers are occasionally used in the production of  products
such  as  rabbit  skins  for  wearing  apparel  and  feathers for
stuffing furniture and bedding items.

A 1970 survey by the USDA found that  only  0«6  percent  of  the
plants  did  not salvage offal0  Of the 99.4 percent that recover
byproducts^ 70,8 percent of the plants sold offal to Tenderers, 1
percent gave offal to  renderers,  26.6  percent  rendered  offal
onsite,   and 1 percent dumped or burned the collected offal.  The
same stud/ revealed that blood was salvaged by  8508  percent  of
the plants.  It was sold to renderers by 54.6 percent,, given away
by  7  percent, rendered onsite by 22,U percent, and dry disposed
by 1.8 percent.  Feathers were not recovered by  0«4  percent  of
the  plants;  they  were salvaged arid sold by 71.,6 percent, given
away by 0.8 percent^ rendered onsite by 25-9 percent, and  burned
or dumped by 1.3 percent.*

Removal  of offal and fea-thers from flow-away waste water streams
is  defined  as  byproduct  recovery.   Almost  all  plants   use
screening  equipment for this purpose.  The most common equipment
arrangement is small mesh  (to 200  irtesh)  rotating  or  vibrating
screens  followed  by stationary protective screens  (1/U- to 1/2-
inch openings)  to collect any overflow.   This  arrangement  will
remove the bulk of the solids-

Gravity  separation  basins  or air flotation systems are usually
used following screening to remove grease and  suspended  solids.
This  is defined as in-plant primary treatment.   (A more detailed
description of primary treatment is found in Section VII of  this
report-)

The  byproducts,  which  are continuously screened from the flow-
away systems or are bulk handled in dry evisceration, are  loaded
into  offal  trucks  for  delivery to rendering plants^  When the
offal is rendered onsite—at the processing plant location but in
a separate billding  the  byproduct  materials  may  be  conveyed
continuously to the rendering system.

Bloodff  on t-ie other hand, is usually vacuumed or pumped from the
blood tunnel to a holding tank.  Lungs are frequently mixed  with
the  blood  in  the  holding  tank0   These byproducts are either
dumped onto feathers in the offal truck or tanked for delivery to
the rendering plant.  The latter is  used  if  the   renderer  has
separate  blood  processing  equipment.   Otherwise  the blood is
mixed with the feathers and they are rendered together.
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Plant Cleanup

Normal plant cleanup practice is for  a  light  washdown  of  the
floor  during  short  break  periods;  for a complete washdown of
floors, sometimes including the blood tunnel, and of most of  the
processing  equipment  during the lunch break; and for a thorough
plant cleanup and general sanitation at the end of the processing
day.  In addition, the floors and some processing  equipment  are
frequently  rinsed  just  prior to the start of a production day.
Spills are cleaned up with water on an as-needed basis.

Maintenance of valves and hoses and use of high-pressure  nozzles
can  help  to  reduce the volume of water used for plant cleanup.
The waste load associated  with  plant  cleanup  can  be  further
reduced  by  dry sweeping and scraping floors and tables prior to
washdown.  Gross solids  collected  by  dry  cleaning  should  be
placed  in containers and sent to rendering.  Dry cleaning of the
blood tunnel  is  particularly  important  because  of  the  high
pollutional strength of blood.
        POULTRY FURTHER PROCESSING MANUFACTURING PROCESS

The  major  limitation  manufacturing  processes  in  plants that
further  process  poultry  are  receiving  and  storage;  thawing
operations;  cutting  and boning; dicing, grinding, and chopping;
cooking; batter and  breading;  mixing  and  blending;  stuffing;
canning;  final  product  preparation;  freezing;  packaging  and
shipping.  Because of  the  similar  operations  and  facilities,
shipping is grouped with receiving and storage for the discussion
below.   Associated  with  these  processes  are  subprocesses of
product cooling and plant cleanup.

These manufacturing processes contribute in  varying  degrees  to
the  raw waste load from further processing operation.  It should
be noted that the plant raw waste load includes the effect of in-
plant primary waste treatment.  The source and  relative  amounts
of  waste  load  for each manufacturing process are identified in
the following descriptions.  Cleanup of equipment and  processing
areas  and  the  associated waste generated are also described in
the following discussions.


                Receiving. Storage, and Shipping

Poultry meat used as raw material and  nearly  all  the  finished
products  in  a  poultry  processing plant, except certain canned
products, require refrigerated or freezer storage.   Poultry-type
raw  materials  are  brought  into  further  processing plants as
carcasses, cut-up parts, and  deboned  meat,  although  the  vast
majority  is whole carcasses.  Further processing plants that are
an adjunct  operation  to  poultry  slaughtering  plants  usually
receive  fresh  ice-packed poultry meat; plants isolated from raw
material  sources   usually   receive   frozen   poultry   meats.
Seasonings,  spices,  and  chemicals  are usually received in dry
                                 27

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form and stored in dry areas  convenient  to  sauce,  spice,  and
batter and breading formulation areas.

The cleaninq ot storage freezers is mainly a dry process and only
on  rare  occasions,  such  as  defrosting of a treerer, would it
generate a wasto water load.   Refrigerated  storage  space  do^s
require  daily  wash  down, particularly ot the floors whore meat
juices and particles have accumulated from the sorted  materials.
Although  the  industry  encourages  dry  cleaning  of all floors
including storage  areas  prior  to  wash  down,  actual  cleanup
practices frequently do not include the dry cleanup.

Shipping  almost  always  involves truck transportation.  Storage
includes the movement in and out of storage facilities within the
plant.  The primary source of waste from these operations  occurs
in  the transport of raw materials between storage and processing
areas within the plant; transport of finished products and  other
raw  materials usually generates Ittle or no waste because of the
type  of  packaging  used.   Further  processing   raw   material
transport  is  largely done in stainless steel carts or vats that
must be  thoroughly  washed  and  sanitized  between  uses;  this
cleaning  results  in  the loss of meat juices and particles into
the sewer.
                             Thawing

Frozen  poultry  carcasses  and  raw  meat  received  by  further
processing  plants are thawed by immersion in or by spraying with
water, or by thawing in air.  The raw material must be adequately
protected from cross-contamination.   In  immersion,  poultry  is
submerged in tanks or vats of lukewarm potable water for the time
required  to  thaw the poultry throughout.  At no time should the
thawing media in which poultry is immersed  exceed  21°C   (70°F).
Ice  or other cooling agents may be utilized if necessary to keep
the thawing water within the acceptable range.  The vats used for
thawincr range from pushcarts of 10 to 20 cubic feet in volume  to
permanently  installed  tanks  up to about 50 feet in length.  To
enhance thawing, water may be continuously added or flexible  air
hoses  may  be  inserted  to  induce agitation.  In thawing units
which have no freshwater added (no overflow) or where the thawing
water leaves the unit for reconditioning prior  to  returning  to
the thawing unit, the water is not allowed to exceed 10°C  (50°F).

Complete  thawing  is necessary to permit thorough examination of
ready-to-cook poultry prior to any further processing.  When  the
poultry  has  adequately  thawed for reinspection* the product is
removed from the water and  drained.   The  practice  of  placing
frozen  poultry  into  cooking kettles, without prior thawing, is
permitted only when representative samples of the entire lot have
been thawed and found to be in  sound  and  wholesome  condition.
Thawing  may  be  accomplished  in cookers where the water can be
heated  to  enable  the  cooking  process  to  begin  immediately
following  completion  of  thawing.   It is required that thawing
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practices and procedures result in no net gain in weight over the
frozen weight.


When whole carcasses or  parts  are  thawed  for  repackaging  as
parts,  USDA  regulations  prohibit recooling the thawed parts in
slush ice.  However, they may be held in  tanks  of  crushed  ice
with the drains open pending further processing or packaging.

Wet  thawing  of  further  processing raw materials generates the
largest quantity of contaminated waste water.  The water used  to
thaw the poultry is in contact with the meat and thereby extracts
water-soluble  salts  and  accumulates particles of meat and fat.
The water used in thawing is dumped into the sewer during  and/or
after  thawing  is  complete.   In addition, a waste load results
from cleanup of the thawing systems.  The waste load generated in
dry thawing is from the thawing materials dripped  on  the   floor
and the washing of these drippings into the sewer.


                       Cutting and Boning

Cutting  of poultry is normally the first further processing step
for fresh ice-packed and just-thawed poultry.   Cutting  involves
disjointing  and  sawing of poultry into the normal parts such as
wings, breasts, and drumsticks.  It also  may  include  skinning.
The  waste  load  generated  from cutting results from the use of
water by the personnel  involved  in  the  operation  during the
operating  day and from cleanup of the floors and equipment.  The
waste materials include skin, fat, meat  tissue  and  bone   dust.
The  waste  load from cutting does not appear to be large and can
be reduced to an insignificant amount by dry cleaning  of  floors
and equipment prior to washdown.

Boning  is the separation of meat from bone.  This can be done on
either raw or cooked poultry.   Frequently  turkeys,  because  of
their  size,  are boned raw; chickens and similarly sized poultry
are boned either  way.   The  ultimate  product  use  of  poultry
usually  determines  whether  a  product is boned before or  after
cooking.  Raw boning is usually  done  by  hand,  whereas  boning
cooked  poultry can be done by hand, by mechanical means, or by a
combination of the two methods, providing all  bone  is  removed.
The  waste  load  from  boning  results  from frequent washing of
knives, cutting boards, pans, and  operators1  hands  during the
operation  day;  from  the  rinsing  of  floors and tables during
breaks and lunch;  and  from  the  dismantling  and  cleaning  of
mechanical  equipment.   The  pollutants may include meat juices,
and meat and fat tissue.  Bones are collected as raw material for
rendering.


                 Grinding, Chopping, and Dicing

Many poultry products,  such  as  patties,  rolls,  and  luncheon
meats, require size reduction of boned meat.  Grinding, chopping,


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or  dicing  vary  the  degree  of  size  reduction,, with grinding
producing the greatest degree of  size  reduction,,  chopping  the
next,   and   dicing   the   least.   These  operations  are  all
accomplished by mechanical equipment.  In grinding^ the  meat  is
forced  past  a  cutting  blade and then extruded through orifice
plates having holes between 1/8 and 3/8 inch;  chopping  likewise
is  usually  accomplished  by  forcing the meat past a cutter and
through an orifice platec but with holes greater than 3/8 inch in
diameter.  Dicing,; on the other hand,  is  more  like  a  cutting
operation  in  that it makes distinct cuts in the meat to produce
square-shaped chunks of meat.  Waste  loads  are  generated  from
these   operations  by  spillage  in  handling  and  movement  of
materials and  in  cleanup  of  equipment.   These  manufacturing
operations  can be among the major contributors to the waste load
in poultry further processing plants as  a  result  of  equipment
cleanup.   Because  these processing steps involve size reduction
of poultry meats, meat and fat particles tend to  coat  equipment
surfaces  and  collect  in  crevices,  recesses,  and dead spaces
within the equipment*  Of course^ tHe finer  the  particle  size,
the  greater  the tendency for coating and hanging up of material
in the equipment.  All of  these  materials  are  removed  during
cleanup  and  are  washed inro the sewer.  Any piece of equipment
that is used in size reduction  is  cleaned  at  least  once  per
processing  day and may be rinsed off periodically throughout the
dayp thereby contributing substantially to the waste load.


                             Cooking

All further processed poultry products are, by definition, cooked
at some point in processing-  This is done in  preparation  of  a
final   product  or  in  preparing  whole  birds  for  subsequent
deboning,  the  latter  applying   particularly   in   processing
chickens.   Fully cooked poultry products are frequently prepared
in further  processing  operations,  especially  for  the  hotel,
restaurant., institution, and fast-food outlet market.

Most  poultry products are cooked by immersion in water in steam-
jacketed ojcen vats.  Gas-fired ovens are used for  some  products
and a small number of microwave ovens are also in use in place of
immersion cookers.,  Deep-fat frying is used for breaded products;
this  is  discussed  in  the  following  subsection,  "Batter and
Breading. "

Chicken par is, whole birds, and products such as rolls and loaves
are cooked oy immersion in hot water cookers.  Overflow wiers are
used in these cookers to collect edible  chicken  or  turkey  fat
during the actual cooking operation.  At the end of the operating
day,  the  cooking vats are dumped to the sewer-  The waste water
volume is small in comparison to the total water use in  dressing
plants;  i*;  is  more  significant in plants that further process
only.  However, the waste load is exceptionally high.   A  sample
of  this v/aste water was found to contain a BOD5_ concentration of
17,000 mg/1.  Spices and preservatives are added to  the  cooking
water.   These  additives plus other pollutants accumulate during
                                  30

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the cooking of the poultry and contribute  substantially  to  the
plant waste load.


The  gas-fired  ovens  require  essentially  no  water  in  their
operating cycle.  A small quantity of  steam  may  be  added  for
humidity  control,  but  this is usually vented through the stack
system.

The use of microwave  ovens  frequently  requires  a  preliminary
injection of spices and preservatives by means of multiple needle
injection  equipment such as is used in ham and bacon processing.
The pickle solution remaining at the end of the operating day  is
dumped  into  the  sewer.   The  quantity  of water is small, but
again, the strength  is  very  high  as  a  pollutant.   A  steam
atmosphere  is used in some microwave ovens; this would produce a
small stream of condensate that may be a high-strength pollutant.

All cooked products are cooled before any further  processing  of
the  product.   The most common cooling technique is by immersion
in a cold-water  vat  which  has  a  continuous  overflow.   This
overflow  and  the  cleanup  of  the  vat  at  the end of the day
generates a waste water stream of significance.  Also because  of
the  direct  contact  between the poultry meat and the water, the
pollutant strength of the waste water is substantial.

Cleanup of these cookers requires  dumping  the  liquid  contents
followed  by  a  thorough washdown of all surfaces exposed to the
poultry products.  The cleanup after dumping results in  a  waste
water stream and waste load.
                       Batter and Breading

Fully  cooked  poultry  parts or fresh fabricated products may be
battered and breaded to produce a desired finished product.   The
batter is a water-based pumpable mixture, usually containing milk
and egg solids, flour, spices, and preservatives.  A new batch of
batter  is  prepared  each  operating  day.  The batter is pumped
through the application equipment and the excess  flows  back  to
the  small  holding  tank.   Some  of  the  batter  clings to the
application equipment and this is cleaned off during the day.  At
the end of the day, the remaining batter is dumped to the  sewer.
It  is  a very small quantity—between 5 and 10 gallons—although
it is certainly a high-strength pollutant.

The breading is a mixture of solids which are  deposited  on  the
poultry  product after the batter is applied to hold the breading
on.  There is no liquid involved in breading  the  products,  and
the residual solids are not disposed of into the sewer.

The  breading  is  "set,"  "browned," or cooked by frying in deep
fat.  The breaded products are conveyed through a deep-fat  fryer
that is either directly gas fired or is heated by the circulation
of hot oil from a heater separate from the fryer.  This vegetable
                                 31

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oil is reused repeatedly,  when the rare occasion occurs in which
the  oil  must  be disposed of, the oil is shipped to a renderer,
rather than dumped to the sewer.


The cleanup of the batter and breading equipment results in  some
waste  water  and waste load.  However, the relatively small size
of the equipment results in a water volume and  waste  load  from
cleanup that are relatively minor.


                       Mixing and Blending

Some   of   the   further  processed  products  include  numerous
ingredients such as the  ground  or  chopped  meat,  dry  solids,
spices', and water.  The required intermixing of these ingredients
will  also  vary,  depending on the product, from a mild blending
action to an intensive high-shear  mixing  action.   Gravies  and
sauces  are  also  prepared  in mixers that usually include steam
jacketing.   The  ingredients  are  either  pumped  or   manually
transported  to  the  mixing equipment for the preparation of the
batches of the product mix..

Solid wast^ materials are  generated  from  these  operations  by
spillage ir the handling and movement of materials and in cleanup
and preparation of equipment for different types of products.

These  manufacturing  operations are among the major contributors
to the wast? load in a poultry further processing only plant as a
result of equipment cleanup.  Since this processing step involves
the  intima :e  mixing  of  meat  and  other  materials   in   the
preparation  of  stable  mixtures,  these  materials tend to coat
equipment surfaces and collect in crevices,  recesses,  and  dead
spaces  in  equipment™  All of these materials are removed during
cleanup and washed into  the  sewer.   This  is  in  contrast  to
larger-size  particles  that  can be readily cleaned from a floor
prior to washdown and thereby reduce the raw waste  load  in  the
waste  water  stream.  Any piece of equipment that is used in any
of these operations is cleaned at least once per  processing  day
and  may  be  rinsed off periodically throughout the day, thereby
generating a fairly  substantial  Quantity  of  waste  water  and
contributing to the raw waste load.


                     Stuffing and injecting

Following  the preparation of a stable mixture of ingredients for
a processed poultry product, the mixture is transported either by
pump or in a container to a  manufacturing  operation  where  the
mixtures  are formed into the finished products.  Sausage casings
are commonly  used  as  containers  in  this  operation.   Either
natural  casings,  which  are  animal  intestines,  or  synthetic
casings may be used in producing these kinds of products.
                                 32

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In casing stuffing, a product mixture is placed  in  a  piece  of
equipment  from which the product mixture is either forced by air
pressure or  is  pumped  to  fill  the  container  uniformly  and
completely  to  form the shape of the finished product.   Water is
used to lubricate casings for use in the stuffing operation.


Whole bird stuffing, primarily with turkeys, involves  pumping  a
stuffing  mixture  into  the body cavity of the dressed bird at a
stuffing station,  followed  by  trussing  and  freezing  of  the
stuffed bird.

Injection  of  whole  birds  with  edible  fats and oils, such as
butter, margarine, corn oil, and cottonseed oil, is often done to
enhance palatability.  Again this is primarily done  with  turkey
carcasses.   This  is  normally  accomplished  by inserting small
perforated needles into the carcass in such a manner as to direct
the injected fat  or  oil  between  the  tissue  fibers.   It  is
preferred  tc  inject  longitudinally  into  the  carcass without
penetrating the skin of the carcass.  Thus the  intact  overlying
skin will retard escape of the injected materials.  The injection
material  can  be  used  one  day  after preparation, but must be
dumped at the end of the  second  processing  day.   Most  plants
minimize  or  avoid  any  dumping  of  this high-cost material by
preparing only the quantity that will  be  needed.   When  it  is
dumped, it is discharged into the sewer.

The  primary  source  of waste load and waste water occurs in the
cleanup of the equipment used in this  operation.   The  residual
mixtures  left  in  the equipment contribute significantly to the
waste load because of their propensity to stick to most  surfaces
that  they  come  in contact with and to fill crevices and voids.
All equipment used in this operation is dismantled at least  once
a  day for a thorough cleaning.  Between preparation of different
products, the equipment may be rinsed off with clear water.   The
end-of-the-day  cleanup is designed to remove all remnants of the
mixtures handled by the equipment and  this  material  is  washed
with  the waste water into the sewer, thereby contributing to the
waste load,

Some spillage of material occurs  in  this  operation.   Spillage
occurs  during  the  transport  of the material from grinding and
mixing  to  the  stuffing  operation,  and  particularly  in  the
stuffing  injecting  operation  when  the material being extruded
exceeds the capacity of the casing or whole bird, and overflows.
The containers used to hold the canned poultry food products must
be prepared before filling and covering.  The cans are thoroughly
cleaned and sterilized.  The wet cans are  transported  from  the
preparation area to the processing area for filling and covering.
Water  is  frequently  present  all  along  the  can  lines  from
preparation to filling and covering.  The  cans  go  through  one
                                 33

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last  steaming  just  before  entering the can filling area.   Can
filling can be done by hand or mechanically.   However, canning of
whole birds or disjointed parts necessitates hand filling.

Can  filling  by  machine  is  a  highly  mechanized   high-speed
operation.   It  requires the moving of the poultry food products
to the canning equipment and  the  automated  delivery  of  those
products into a container.  The combined high speed and design of
the  equipment  results  in  an appreciable amount of spillage of
product as the cans are  filled  and  conveyed  to  the  covering
equipment.   At  the can covering station a small amount of steam
is introduced under the cover or a light vacuum  is  pulled  just
before the cover is sealed to create a vacuum within the can when
it  cools.   Steam  use  also  generates a quantity of condensate
which drains off the cans and  equipment  onto  the  floor.   The
operation  of  the  filling  and  covering equipment results in a
substantial quantity of waste  water  containing  product  spills
that  is  wasted  to  the  sewer.   Filling cans by hand does not
appear to generate as much spillage.  Canning  plants  that  have
more  than  one  filling and covering line will have a waste load
that is generally proportional to the number  of  such  lines  in
use.

All  of the equipment used in filling and covering cans is washed
at least once per day at the end of the processing period.  If  a
can  filling  machine is to be used for different products during
the day,  it  will  usually  be  cleaned  between  product  runs.
Poultry  products  are  frequently canned with gravy-type sauces.
This type of canned product results in greater  contamination  of
equipment  wash  water  because  of  the  tendency of the product
mixture to coat surfaces it comes in contact with and to fill all
dead spaces and crevices in  the  iequipment.   Highly  mechanized
equipment with many moving parts is designed to be cleaned intact
rather  than  being  dismantled first, as is much of the grinding
and mixing equipment.  Cleaning the equipment while it is  intact
requires  a  high-velocity water stream or jet of steam to remove
all food particles from the equipment.  The tendency of operating
personnel is to use greater quantities of water than necessary to
clean the equipment.  This results in large quantities  of  waste
water with substantial waste loads from canning operations.

The  equipment  used  in transporting the meat product to the can
filling stations also must be cleaned after it has been used on a
specific product, and it is always cleaned  at  the  end  of  the
processing  day.   The product characteristics that contribute to
large waste loads, as described above, also generate large  waste
loads in cleanup of the transport equipment as well.

Canned poultry food products are stabilized by heat processing to
destroy bacteria inside the canned product.  This is accomplished
by  cooking  or by retorting, which is the pressurized cooking of
canned products.  Live steam is used as  the  heating  medium  in
retorting,  and it is common practice to bleed or vent steam from
the retort vessels to maintain  the  cooking  pressure.   Cooking
without  pressure  is  used  for  cured  boneless  canned poultry
                                 34

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products;  the product is considered perishable and must  be  kept
refrigerated.    virtually  no  waste  water  or  waste  load  is
generated  by the retorting or cooking operations unless a can  in
a  particular  batch  should  accidentally  open  and  spill  its
contents;  this requires the wasting of the contents of  that  can
and  the cleanup of the cooking vessel.  This rarely happens, and
the retorts or cooking vessels, as a matter of  normal  practice,
are not cleaned.  The cans that are placed in cooking vessels are
normally free of any potential source of waste load,

                    Final Product Preparation

Many  of  the  final  products from a poultry plant that includes
further processing are ready  to  serve  after  heating  and  are
prepared  for  the  hotel,  restaurant,  and institutional trade.
These products are portion controlled, may have gravy or a  sauce
added,  and are packaged in containers of an appropriate size and
design for immediate heating and serving.  Poultry meat  patties,
slices of turkey loaf, and chicken parts are examples of the type
of meat product prepared in this manner.

Equipment  is used to convey, slice, and deposit the meat product
into containers.  The same equipment delivers and adds the  sauce
or  gravy  to the meat in the container, as required for specific
products.   As the final  operation,  this  equipment  closes  the
individual containers.

All  of the equipment surfaces that contact the food products are
cleaned at the end of each  processing  day,   A  change  in  the
product  during  the  day may require cleaning some components of
the equipment.  Material spills are cleaned up immediately.   All
of  the  materials  washed  from the equipment are carried to the
sewer in the wash water.  The volume of water and the waste  load
from cleanup are relatively small from this processing operation.


                            Freezing

The  first  step  in  the  freezing  of further processed poultry
products is usually accomplished by blast freezing, in which  the
product  is  frozen by high-velocity air within the range of -29°
to -40°C  (-20° to -40°F), or by first passing the product through
a carbon dioxide or nitrogen tunnel in which the change in  phase
of  carbon  dioxide  or  nitrogen from liquid to gas causes rapid
surface freezing.   The  products  are  then  placed  in  holding
freezers  in which the temperature is maintained between -29° and
-18°C (-20° and 0°F).  The waste load associated with freezing is
normally small or insignificant because  packaging  isolates  the
product  from  contacting  any  part  of the freezing units.  IQF
(individual quick-frozen) products, however, are  usually  frozen
by  conveying, in the unpackaged State, through carbon dioxide or
nitrogen freeze tunnels.  Product contact with the conveying belt
results in material transfer to  the  belt,  requiring  that  the
conveying  belt be continuously washed.  This washing of the belt
can contribute moderately to the raw waste load.
                                 35

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                            Packaging

A variety of packaging techniques are used in the poultry further
processing industry.  These  techniques  include  the  limitation
treated  cardboard  package, the plastic film sealed under vacuum
or the Cry—O-Vac type  of  package,  the  bubble  enclosure  type
packages  used  for  sliced  luncheon  meats,  and  the boxing of
smaller containers or pieces of finished  product  for  shipment.
In  some techniques of packaging, a substantial amount of product
handling is involved.  This may result in  some  wasted  finished
product.   However,  the  size  of  the pieces of wasted finished
product are such that there is little reason for it to be  washed
to  the sewer.  Instead, it should be returned for subsequent use
in another processed product or directed to a renderer.

Cleanup of the equipment would be the only time when water  would
be  generated  by  the  packaging operation.  Small quantities of
water are adequate for cleanup of this equipment, and only  small
quantities  of  waste  would  be  generated  in  cleanup  of  the
packaging equipment,


                   ANTICIPATED INDUSTRY GROWTH

The estimated value of the poultry products shipped in  1972  was
$3.7  billion  and  was expected to rise to $5.0 billion in 1973.
The U. S. Industrial  Outlook:   197**7  estimates  a  six-percent
growth  rate  for  the  poultry  industry  in 1974,  However, the
growth of dollar volume in the  industry  has  averaged  about   9
percent between 1967 and 1973.  Therefore it can be expected that
the  dollar growth rate will be somewhere between 6 and 9 percent
over the next several years.

Factors that should contribute to  growth  can  be  distinguished
from   those  that  act  to  restrain  this  growth.   A  growing
population and rising family incomes will  continue  to  maintain
consumer  demand for poultry products.  Per capita consumption of
poultry has risen steadily over the past twenty years,  as  shown
earlier  in this section.  In fact, the per capita consumption by
weight of turkey and chicken has risen at an average annual  rate
of  about  3.5 percent over the period of 1962 to 1972 to a value
of about 52 pounds in   1972.   Rapid  growth  in  the  volume  of
further  processed  poultry products is anticipated in the coming
years.  This is based on the fact that both parents  are  working
in  many  families  and  as  a  result will tend to purchase more
prepared foods.

The primary restraint to continuing growth of poultry products is
high prices.  When poultry prices approach those for  red  meats,
their sales dip; however, the net effect of this over a period of
time  is  a  lowering   in poultry  prices.  But if all meat prices
remain  high, consumers  reduce their overall consumption  of  meat
products  by  substituting  other foods.  The direction and degree
of these effects are  largely indeterminant at this time.
                                 36

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                           SECTION IV

                     INDUSTRY CATEGORIZATION


                         CATEGORIZATION

In developing effluent limitations guidelines and limitations  of
performance  for  the poultry processing industry, a judgment was
made as to whether limitations and standards are appropriate  for
different  segments  (subcategories}  within  the  industry.   To
identify any  such  subcategories,  the  following  factors  were
considered;
     o  Type of raw material,
        etc. :
broiler, turkey, small game.
     o  Finished product;

     o  Processing operations;

     o  Plant size;

     o  Plant location and age;

     o  Waste water characteristics and treatability.

After considering all of these factors, it was concluded that the
poultry processing industry consists of five subcategories.  Four
of the subcategories comprise the poultry dressing segment of the
industry,  the  fifth  sufacategqry  is for plants that do further
processing only.  The subcategories are defined  as follows:

     1B  Chicken processor—a chicken dressing plant that primarily
         slaughters broilers; and may also cut up* further process,
         and/or render on the same plant site.

     2.  Turkey processor—a turkey dressing plant that slaughters
         turkeys, primarily; and may also cut up and further process
         concurrently or seasonally, and/or render on the same
         plant site.

     3.  Fowl processor—a fowl dressing plant that primarily
         slaughters light or heavy fowl  (mature  chickens); and may
         also cut up, further process and/or render on the same
         plant site.  Geese and capon dressing plants are included
         in this subcategory.

     4C  Duck processor—a duck dressing plant that slaughters ducks
         primarily; and on the same plant site may also cut up,
         further process, and render.

     5.  Further processing only—a poultry plant that conducts
         only furtner processing operations, with any type of
         bird, but with no onsite slaughtering.
                                 37

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The SIC grouping covered in this study includes rabbit and  small
game dressing plants.  Based on the findings of this study, it is
concluded  that  such  plants  need not be considered in effluent
limitations because the volume of their water use  excludes  them
from  the permit program, the plants tend to be small and located
within municipal waste water treatment  system  access,and  there
are  very  few  such plants in operation.  Egg plants and soup or
frozen dinner plants are not included in the poultry industry  as
defined herein.

A  schematic drawing depicting the categorization is presented in
Figure 3.  The industry is basically split  between  plants  that
slaughter  and those that do not.  There is also a reasonable and
significant difference in raw waste load between  those  that  do
slaughter,  based strictly on the type of bird that is handled by
the plant.

Those plants that process more  than  one  kind  of  bird  should
generally  be  classified  in  the  subcategory for the bird that
accounts for  the  largest  volume.   If  a  multi-product  plant
handles  different  types  of  poultry  on  a seasonal basis, its
assigned subcategory may vary according  to  the  poultry  it  is
processing   at   any  given  time.   Duck  processors  operating
coincident with a duck feedlot insofar as waste load  or  treated
discharge  is  concerned,  may  be best described as "integrated"
facilities.  Provisions for  such  facilities  are  discussed  in
Section IX,
                  RATIONALE FOR CATEGORIZATION

                      Type of Raw Material

The  type  of raw material used in a poultry dressing plant is an
important factor in  substantiating  the  categorization  of  the
industry.    The   term  "raw  material,"  in  this  context,  is
synonymous  with  type  of  bird  or  small  game  animal.    The
subcategorization is based on the following types of raw material
as defined:

     1.  Chicken—-primarily broiler, which is a young chicken usually
         between seven and nine weeks old and weighing between
         3.5 and 4.25 pounds.  Chickens that are not classified as
         mature chickens or fowl are also included in this raw
         material group.

     2,  Turkey—a hen or torn turkey of varying age and size.

     3.  Fowl—a mature chicken larger in average size and older
         than broilers; used either as a laying or breeding hen.
         Both light  (laying) fowl arid heavy (breeding) fowl are
         included in this group.  Trie small number of geese, capons,
         roosters, and stags processed are also included here.
                                 38

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                               POULTRY PROCESSING
                                    INDUSTRY
    POULTRY SLAUGHTERING
      & DRESSING PLANTS
                                  FURTHER PROCESSING
                                         ONLY


CHICKENS
 TURKEYS
FOWL
DUCKS
Figure 3.   Categorization  of Poultry Processing Industry

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5.
         Ducks — all those species of birds classified as ducks
         usually of domesticated variety raised in feedlots for
         commercial marketing.

         Smal 1 game — rabbits, pheasants , guineas, squab, and any
         other small game animals that are slaughtered tor commercial
         use,
The  small game portion of this industry represents less than one
percent of industry production.3  The birds in  this  subcategory
are processed in plants handling other raw materials, which would
contribute  the  more  significant  waste  load, or in a very few
specialty plants that typically have seasonal  operations/  small
waste water volumes, and are discharging into municipal treatment
systems.   While a specific subcategory has not been defined, nor
does it appear warranted to do so, data and discussion  of  these
plants  will  be  included  wherever  appropriate  to amplify the
discussion of poultry processors.

A clear distinction in subcategories based on  raw  materials  is
obtained when the raw waste load basis is weight of BOD5 per unit
weight  of  LWK,   The  alternative  of BOD5 weight per number of
birds (or animals)  killed is less useful because of variations in
bird size which would not be accounted for but which would affect
the results.  The poultry processing industry  records  both  the
weight and number of birds processed daily as a matter of routine
accounting*
                        Finished Product

The finished product of a plant is not a factor in categorization
of the poultry processing industry and thus confirms the proposed
categories.  Basically, the poultry industry produces:

     o  Fresh and frozen whole birds;

     o  Fresh and frozen parts cut from birds;

     o  Processed poultry products — frozen, canned, cooked, etc.

The  last  of  the  above  list  includes  a  myriad of processed
products — other than soups and TV dinners Which are not  included
in  this  industry.   They  are  produced  in  further processing
operations which are found both in dressing plants and in  plants
that further process only.

The  primary finished product distinction is made between dressed
birds and processed poultry products.   The  water  use  and  raw
waste load resulting from production of these two different types
of  product  differ substantially.  However, dressing plants also
may produce processed products.  The industry subcategories  must
be unique, distinct, and separate from one another.  There should
be  no  overlap  nor  commonality among the sufccategories.  Thus,
while   the   proposed   categorization   conceptually   reflects

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difterences   associated   wi-tfi  finished  products,  the  actual
criterion for  categorization  is  more  accurately  on  in-plant
processing  operations,  rather  than  finished  product, and the
categorization is thereby further substantiated.


                      Processing Operations

In-plant processing operation^  are  the  basic  distinction  arid
substantiation   in   categorizing  poultry  dressing  plants  as
separate from further processing only  plants.   The  descriptive
title  of  each  group of plants reflects the predominant type of
processing operation in use by  the  plants.   In  this  context,
predominant  means  the  primary  water  consumer  and waste load
generator.    Dressing   plants,   as    indicated    previously^
occasionally  do include further processing operations.  However,
the water use and waste  load  from  the  dressing  operatipn  is
several  times  that from further processing.  In fact, the waste
load from plants combining bo|:h types of operations was found  to
be very close to that from plants that only slaughter.

The  poultry  processing  industry makes use of the same terms to
distinguish the different types of processing  operations,  i.e.,
dressing   and  further  processing.   This  avoids  problems  of
definition   or   interpretation   in   assigning    plants    to
subcategories.    Thus   the  categorization  based  on  in-plant
processing operations is established as credible,  rational,  and
workable.                                                  !
                           Plant Size

Plant  size  per  se is not a factor in categorizing the industry
which substantiates the proposed categorization.  There is a wide
range of size of plants in the  various  subcategories;  however,
the  range  in  raw  waste  load  from plants grouped by size was
essentially equal for  large and small plants.  Waste water volume
and raw waste load per unit  of  production  were  found  to  be
independent of plant size.


                     Plant Age and Location

Plant age and location do nqt influence poultry processing plants
such  as to require consideration in categorization and therefore
substantiate the proposed categorization of the industry.  Age as
a potential factor in  categqrization  at   least  would  have  the
advantage   of   quantitative   definition.    However,  industry
experience and practice precludes even that utilj cy for  the  age
factor.   In-plant  processes  are  continually  oeing updated or
improved, so even old  buildings may have very c1 crent  prpcessing
equipment.    Thus,    age  is  difficult,  if   tot  realistically
impossible, to define.  In addition, a cursory analysis  revealed
no apparent relationship between reported  plant age and raw waste
load.

                                      41

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The poultry processing industry, as reported previously, tends to
b*i highly concentrated in a few regions of the country.  However,
there  is  no discernible relationship between plant location and
raw wa-^te load.

Thus,  plant  age  and  location  are  not  relevant  factors  in
categorizing  the  poultry  processing  industry,  which  further
confirms the proposed categorization.


          Waste water Characteristics and Treatabilitv

Industrial practices within the poultry processing  industry  are
diverse  and  produce  variable  waste  loads.  It is possible to
develop a rational division of  the  industry,  however,  on  the
basis  of  factors  which  group  plants  with  similar raw waste
characteristics.  These raw  wastes  are  amenable  to  the  same
treatment    techniques.     Thus   waste   characteristics   and
treatability substantiate the categorization.

The waste water characteristic used as the basis in  categorizing
the  industry  is  five-day  biochemical  oxygen demand  (BOD5) in
units per 1000 units live weight killed (LWK) :  kg  BOD5/1000  kg
LWK  (Ib  BOD5/  1000 Ib LWK).  BOD5 provides the best measure of
plant operation and treatment effectiveness among the waste water
parameters measured, and more data are available  for  BOD5  than
for   any  other  parameter?   Suspended  solids  data  serve  to
substantiate the conclusions developed from BOD5,, in categorizing
the industry.

The major plant waste load is organic  and  biodegradable;  BODI5,
which  is  a  measure of oiodegradability, is the best measure of
this type of loading  entering  a  waste  stream  from  a  plant.
Furthermore,  because  biological waste treatment is a biological
process, BOD5 also provides a useful measure  of the  treatability
of  the  waste  and  the  effectiveness of the treatment process.
Chemical oxygen demand  (COD) measures total organic  content  and
some  inorganic  content,  COD is a good indicator of change, but
does not relate directly tc biodegradation,   and  thus  does  not
indicate  the  demand  on  a biological treatment process or on  a
stream.

^s described in more detail in Section V,  differences  exist  in
the  average  BOD5  loads  for  raw  wastes for the five distinct
groupings of poultry processing operations.   As  defined  above,
these   groupings    (by   plant   type)   are   substantiated  as
Tabcategories on the basis of waste load.   Table  8  presents   a
summary   of   average   plant   operating  parameters   for   each
subcategory; the parameters include production,  water  use,  and
3OD5 loading in the raw waste.

A   number   of   additional  waste  load  parameters   were   also
considered.  Among these were   nitrites  and  nitrates,  Kjeldahl
nitrogen,  ammonia,  total  dissolved solids, and phosphorus.  In
each case, data were insufficient to justify  categorizing on  the
                                     42

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Table 8.  Production, Waste Water Flow, and Raw Waste Loading

Production
Average, birds /day
Range, birds/day
Number of Plants
in Sample
Average Live Weight
Average, kg/bird
(Ib/bird)
Range, kg/bird
Number of Plants
in Sample
Waste Water Flow
Average, I/bird
(gal/bird)
Range, I/bird
Number of Plants
. in Sample
Raw Waste BODs
Average, kg/kkg LWK
Range, kg/kkg LWK
Number of Plants
in Sample
Chicken
Processors

73,000
15,000 - 220,000
90

1.74
(3.83)
1.45 - 1.97
90

35.4
(9.3)
15.9 - 87.0
88

9.89
3.26 - 26.1 .
60
Turkey
Processors

12,100
2,000 - 30,000
34

8.3
(18.2)
4.1 - 11.4
34

118.2
(31.2)
36.3 - 270.2
34

4.94
0.96 - 9.1
15
Fowl
Processors

34,100
11,900 - 70,000
8

2.3
(5.1)
1.6 - 4.1
8

48.9
(12.9)
11.0 - 159.0
8

15.20
' 11.78 - 23.14.
4
Duck
Processors

6,600
1,900 - 15,000
5

2.9
(6.4)
2.0 - 3.2
5

74.9
(19.8)
71.5 - 78.3
2

7.06
6.59 - 7.52
2
Further
Processing Only

36,700 kg/day FP
(80,500 Ib/day FP)
11,400 - 77,600 kg/day FP
4




12.5 I/kg FP
(1.5 gal/lb FP)
2.92 - 21.34 I/kg FP
4

19.03 kg/kkg FP
16.71 - 22.11 kg/kkg FP
3

-------
basis of the specified parameters; on the other hand, the data on
these parameters helped to verify judgments based upon BOD5.

Judging  from  biological waste treatment effectiveness and final
effluent limits, waste waters from all plants  contain  the  same
constituents  and  are  amenable to the same biological treatment
techniques.  It was anticipated that geographical  location,  and
hence climate, might affect the treatability of the waste to some
degree.    Climate   has  occasionally  influenced  the  kind  of
biological waste treatment used, but has not had an influence  on
the   ultimate   treatability  of  the  waste  or  the  treatment
effectiveness, given careful operation and maintenance.  This  is
discussed in more detail in Section VII of this document.

Waste  water volume and the use of municipal treatment combine as
the primary considerations in deleting  rabbit  and  other  small
game dressing plants from effluent limitations guidelines in this
document.   Relatively  small  output  and  correspondingly small
waste water volume are  typical  of  small  game  plants.   These
plants  also  are located in urban areas with access to municipal
treatment systems.  Thus, there is no  need  to  categorize  this
type  of plant.  Data collected on these plants are reported, but
no effluent limitations guidelines are proposed.
                                      44

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                            SECTION V

              WATER USE AND WASTE CHARACTERIZATION


                   WASTE WATER CHARACTERISTICS

Water is used in  large  quantities  in  the  poultry  processing
industry;  it  is used to convey byproduct and unwanted materials
from processing  areas;  to  condition,  wash,  chill,  and  cook
poultry; as an ingredient in some further processed products; and
to clean equipment and processing areas.  The primary waste water
and  waste  load  sources  in  poultry  processing  plants are as
follows:

     o  Killing and bleeding;

     o  Scalding;

     o  Defeathering;

     o  Evi sc erati on;

     o  Chilling;

     o  Further Processing:
          thaw tanks,
          cooking vats,
          cooling tanks;

     o  Rendering plant condensate and condensor water.

Waste waters  from  poultry  processing  plants  contain  organic
matter  including  grease,  suspended solids, inorganic materials
such  as  phosphates,  salt,  nitrates  and  nitrites,  and  some
coliform  count.  These materials enter the waste water stream as
meat and fatty tissue, offal,  feathers,  body  fluids  from  the
birds   including   blood,   losses   of  materials  in  process,
preservatives and  other  product  ingredients,  and  caustic  or
alkaline detergents.


                    Raw Waste Characteristics

The   raw  waste  load  for  all  subcategories  of  the  poultry
processing industry as discussed  in  the  following  subsections
includes  the  treatment effects of in-plant primary treatment in
devices such as catch basins, skimming tanks, and   lissolved  air
flotation systems.  Raw waste is, by definition, that waste water
entering the biological waste treatment system.

The parameters used to characterize the raw wastf are flow, BOD5,
suspended  solids   (TSS),  grease,  COD  (chemical oxygen demand),
chlorides, phosphorus, Kjeldahl nitrogen, ammonia,  nitrites  and
nitrates,  total volatile solids, and total dissolved solids.  As
                                45

-------
discussed in Section VIT BOD5 is considered to  bep  in  general,
"he  most  representative  measure  of  the  raw waste load.  The
parameter used to characterize the size of a plant  is  the  live
weight  kill  ot  birds  orff  in a further processing only plant,
quantity of processed poultry products produced.  All  values  of
the  waste  parameters  are  expressed  as  kq/kkg of live weight
killed  (LWK) or of finished  product  (FP);  this  has  the  same
numerical  value as lb/ 1000 lb.  At times, some waste components
in effluents are so dilute that concentration  becomes  the  more
significant measure of waste load.  In these cases, concentration
is  reported  as  mg/l? which is equivalent to parts per million.
Production quantities are reported in kg/day and waste water flow
is reported in volume (liters and gallons) per bird.  Waste water
volume is reported on a per bird rather than weight basis because
process water use is more directly related to the number of birds
than to the weight of the birds; and people in the  industry  use
the  per bird frame of reference in describing water use in their
plants.

The  info:onation   used   to   compute   production   and   waste
characteristics data was obtained from questionnaires distributed
to their members by the National Broiler Council, Poultry Science
Association,  Poultry  and Egg Institute of America, Southeastern
Poultry and  Egg  Association,  Poultry  Industry  Manufacturer's
Council, Arkansas Poultry Federation, National Turkey Federation,
Pacific  Egg  and  Poultry  Processors  Association,  Mississippi
Poultry Improvement Association,  and  Alabama  Poultry  and  Egg
Association;  from  waste  water  sampling by North Star staff at
fourteen plants; and from  data  provided  by  companies  in  the
industry,  by  State and municipal pollution control agencies and
sewer boards, by  the  EPA,  and  by  the  U.  S,  Department  of
Agriculture^   Survey  questionnaire  data  were collected on 152
identifiable plants.  Data from 83 plants v?ere adequate  for  use
in  categorization  and  in characterization of the raw waste and
waste treatment practices..  Generally9 information found  in  the
opan  literature  was  not  detailed enough to be included in the
data base.

A summary table of production data, waste water volume,  and  raw
waste   characteristics   is  presented  for  each  of  the  five
subcategories in the following subsections.  The subcategories of
the industry are:

     1.  Chicken processor;

     2.  Turkey processor;

     3«,  Fowl processor;

     4.  Duck processor;

     5Q  Further processing only.

These subcategories are defined in detail in Section IV.
                                46

-------
        processors

These  plants  typically  slaughter  bvciler-size  chickens    and
package  them as ready-to-coos in an ice pack or a cold  pack with
dry ice.  The North Star data ijiol'icJea  responses from 92  chicken
dressing  plants, which accout-t 'f-.jr about  63 percent  of  the  total
live weight kill in the country.  The largest percentage of  these
plants reportedly slaughters <*iid cuts up some   portion  of  their
production.   The  chicken  ^recessing  plants  are divided in the
sample as follows:

     Slaughter only — 21 percent

     Slaughter plus cut-up — 43 percent

     Slaughter plus further process — 0  percent

     Slaughter plus render — 5 percent

     Slaughter plus cut-up and render--  ^S  peroent;

The raw waste characteristics rep^r^ed  in  Table 9  are averages of
data from all of these types of eiiiei:xn ^rocessin?   plJ.nKs?.    The
raw   waste   data  includes  plants  with  aVi. combinations  of
operations in the chicken processing su< category,
The principle  sources  of  waste watier  in  thiF.sc  pl«ntP  are  the
feather  and   offal   flow- away  systems,  which  are  part of the
typical defeathering and  evisceration  oper3tions.    One  of  the
recent innovations introduced into poultry processing plarvtp is a
dry  offal handling  system.   Two chicken processing plants in the
North star sample reported this type of system, and  both  plants
reported lower than  average waste water volumes*            '
Various  water   circulation .«vF+ei.i* 3iv  also j « yse by processing
plants, including  flow-away systems wat«r  reoircnlation  to  the
feather  flume,  chiller overflow water  to Li.-c feather flume, and
slaughtering  plant  raw  waste  water  u:se  in  rendering  plant
barometric  condensers.    The  us«  of  these  options  bonds  to
contribute to the  uniformity  of  t.!, «  raw  v^«st*»  load  for  the
various types of plants  in this subcategory.


Turkey Processors

Most turkey processing plants slaughter  turkeys 8 to 10 Months of
the  year.   Host  of these plants also include further processing
operations, which  may be used up to 12 r-ionths per year.  Like the
chicken processing plants, the waste water comes  primarily  from
the feather and  offal flow-away systems.  During that -time- of the
year  of  further  processing only, frozen t.irr.Veys are nsep as the
raw material and the water used in the thawing tenkc  contributes
the  largest  volume  of waste wafers*  The data on the raw waste
characteristics  of turkey plants Are presented in T^ble 10.


                                 47

-------
Table 9.  Raw Waste Characteristics of Chicken Processors
Parameter
Production
Average Live
Weight
Waste Water
Flow
BOD5
SS
Grease
COD
TVS
TDS
TKN
NH3
NO 3
N02
Cl
TP
Units
birds/day
kg/bird
(Ib/bird)
I/bird
(gal/bird)
kg/kkg LWK
kg/kkg LWK
kg/kkg LWK
kg/kkg LWK
kg/kkg LWK
kg/kkg LWK
kg/kkg LWK
kg/kkg LWK
kg/kkg LWK
kg/kkg LWK
kg/kkg LWK
kg/kkg LWK
	
Average
73,000
1.74
(3.83)
34.4
(9.3)
9-89
6.91
4.21
19.70
13.31
11-67
1.84
0,23
0.0078
0.0069
1.97
0.39
Range
15,000 - 220,000
1.45 - 1.97
15.9 - 87.0
3.26 - 19.86
0.13 - 22.09
0.12 - 14.03
2.04 - 56.81
3.48 - 47.17
3.52 - 45.8
0.15 - 12.16
0.005 - 0.73
0.0 - 0.14
0.0 - 0.037
0.006 - 9.16
0.054 - 2.46
Number of
Observations
90
90
88
60
53
39
31
23
23
15
19
12
14
12
22
                     48

-------
Table 10.  Raw Waste Characteristics of Turkey Processors
Parameter
Production
Average Live
Weight
Waste Water
Flow

BOD5
SS
Grease
COD
TVS
TDS
TKN
NH3
N03
NO 2
Cl
TP
Units
birds/ day
kg /bird
(Ib/bird)

I/bird
(gal/bird)
kg/kkg LWK
kg/kkg LWK
kg/kkg LWK
kg/kkg LWK
kg/kkg LWK
kg/kkg LWK
kg/kkg LWK
kg/kkg LWK
kg/kkg LWK
kg/kkg LWK
kg/kkg LWK
kg/kkg LWK
Average
12,100
8,3
(18.2)

llg.2
(31.2)
4.94
3.17
0.89
7.39
8.36
13.53
0.94
0.15
0.037
0.0013
2.49
0.098
Range
2,000 - 20,000
4.1 - 11.4

36.3 - 270.2

0.96 - 9.1
0.57 - 10.89
0.34 - 1.81
3.07 - 10.95
2.20 - 19.16
1.51 - 38.45
0.38 - 1.89
0.064 - 0.37
0.005 - 0.092
0.001 - 0.002
0.38 - 5.41
0.034 - 0.18
Number of
Observations
34
34

34

15
13
10
5
6
5
5
5
3
3
4
4
                    49

-------
One turkey plant  in  the  North  Star  sample  of  the  industry
rt:ported  having  a dry offal handling system.  No raw waste data
were reported for this plant, however,  and  the  data  on  waste
water volume did not indicate any significant savings.


Fowl Processors

Fowl   processing   plants   are  basically  similar  to  chicken
processing plants except for  the  larger  average  size  of  the
birds.   Fowl  are  usually  processed into the further processed
types of  products  either  onsite  or  in  a  plant  at  another
location.   The  slaughtering  and  eviscerating  of fowl are the
primary sources of the waste water and the raw waste  load.   The
feather  and offal flow-away systems are likewise the major waste
water sources.  In  spite  of  the  higher  average  weight,  the
average  raw  waste  load  of  BOD5 per unit LWK is significantly
higher than that for the chicken plants.  The data on typical  or
average  production, water use, and raw waste characteristics are
presented in Table 11.


Duck Processors

Duck feedlots  are  located  on  the  same  plant  site  as  duck
processing plants in all but one plant in the industry, according
to  the  data  collected  by  North  Star.  This was confirmed by
several duck growers and processors.  The water  flow  and  waste
load   from   a   combined   processing   plant  and  feedlot  is
substantially greater than that from a  processing  plant  alone.
However,  tie  processing  plant  will  be dealt with as a single
source in tnis report and the additional load  from  the  feedlot
will of course be considered and accounted for.

The  slaughtering  and evisceration operations in duck processing
are basically the same  as  that  for  other  poultry,  with  the
addition  of wax dipping for pinfeather removal.  The feather and
offal flow-away systems are again  the  major  sources  of  waste
water  and   raw  waste load.  The waste water and waste load data
presented in Table 12 for two  plants  represent  the  processing
plant  waste  load  only; feedlot waste water and loading are not
included, as described above.


Further Procg ssinq Only

Plants that further process only   (do  no  slaughtering)  prepare
finished  poultry  products  primarily  from  chickens, fowl, and
turkeys.  Cooking is involved in all further  processing  plants,
as  defined  in this study.  These plants remove specific parts of
the birds, such as wings and legs, and then remove the  remaining
meat  from  the  skeletal  structure  of  the birds.  Cooking may
precede or follow this cutting operation.  The meat  is  used  in
large  pieces  or  reduced in size in special equipment.  Various
ingredients are mixed with the  poultry  meat  and  the  numerous


                                 50

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Table 11.  Raw Waste Characteristics of Fowl Processors
i'arameter
Production
Average Live
Weight
Waste Water
Flow
BOD 5
SS
Grease
COD
TVS
TDS
TKN
NH3
N03
N02
Cl
TP
Units
birds /day
kg /bird
(lb/bird)
I/bird
(gal/b±rd)
kg/kkg LWK
kg/kkg LWK
kg/kkg LWK
kg/kkg LWK
kg/kkg LWK
kg/kkg LWK
kg/kkg LWK
kg/kkg LWK
kg/kkg LWK
kg/kkg LWK
kg/kkg LWK
kg/kkg LWK
Average
34,100
2.3
(5.1)
48.9
(12.9)
15.20
10.09
2.32
41.39
18.40
24.88
0.28
0.10
i 0.0044
0-00053
3.99
0.29
Range
11,900 - 70,000
1.6 - 4.1
11.0 - 159-0
11.78 - 23.14
6.11 - 14.94
0.72 - 3.32
24.26 - 58.52
13.10 - 23.71
9.14 - 40.62

—
—
—
—
0.27 - 0.31
Number of
Observations
8
8
8
4
4
3
2
2
2
1
1
1
1
1
2

-------
Table 12.  Raw Waste Characteristics of Duck Processors
Parameter
Production
Average Live
Weight
Waste Water
Flow
BOD5
SS
Grease
COD
TVS
TDS
TKN
NH3
N03
N02
Cl
TP
Units
birds /day
kg /bird
(Ib/bird)
I/bird
(gal/bird)
kg/kkg LWK
kg/kkg LWK
kg/kkg LWK
kg/kkg LWK
kg/kkg LWK
kg/kkg LWK
kg/kkg LWK
kg/kkg LWK
kg/kkg LWK
kg/kkg LWK
kg/kkg LWK
kg/kkg LWK
Average
6,600
2.9
(6.4)
74.9
(19.8)
7.06
4.36
1.86
14.08
7.08
8.30
1.40
0.79
0.030
0.0097
1.44
0.084
Range
1,900 - 15,000
2.0 - 3.2
71.5 - 78.3
6.59 - 7.52
3.47 - 5.24
0.66 - 3.05
13.57 - 14.58
6.69 - 7.48
3.97 - 12.62
0.80 - 2.00
0.062 - 1.52
0.018 - 0.043
0.0014 - 0.018
0.78 - 2.11
0.073 - 0.096
Number of
Observations
5
5
2
2
2
2
2
2
2
2
2
2
2
2
2
                   52

-------
types  of  finished  products  are  formed, cooked, packaged, and
usually frozen.

The waste water and waste load originates primarily in cleanup of
further processing equipment and plant facilities.  The  relative
quantities  of  water  and  waste  load are substantially less in
these  plants  than  in  slaughtering  plants.    The  data   are
presented  in Table 13 on production, waste water volume, and raw
waste characteristics for plants that further process only.

The USDA reports the  number  of  plants  in  the  industry  that
further   process   only   is   288,2  tut  the  19,62.  Census  of
Manufacturers indicates only 18 plants fitting that description.3
Based on the response to  the  questionnaires  and  an  extensive
inquiry  of  the  industry, the number of further processing onl•'
plants was judged to be 18 to 20.  The USDA  figures  undoubtedly
include  plants that are not part of the designated SIC codes for
this study.


Discussion of Raw Wastes

The full tabulation of the raw  waste  characteristics  for  each
subcategory are presented in the preceding tables.  Figures U and
5  present a graphic comparison of average waste water volume and
raw waste loads  for  the  five  subpategories.   The  raw  waste
parameters  of  BOD.5,  suspended  solids, and grease, reported as
kg/kkg LWK, were used in the comparison in Figure  5,  and  waste
water  volume per bird was the basis for Figure 4.  The basis for
the data  for  further  processing  only  plants  was  output  of
finished  product rather than LWK.  The relatively high raw waste
loadings for  further  processing  only  plants  were  presumably
caused, in part, by the lack of any in-plant primary treatment in
three of the four plants.

All four plants in the sample reported using municipal treatment.
The  differences  in  the  average  waste load are apparent.  The
averages of course represent ranges of values, as reported in the
tables of data, and  there  is  overlap  in  these  ranges.   The
average  value  of  the  waste  parameters  for  each subcategory
includes those plants that also cut-up, further  process,  and/pr
render  on  the  same  plant  site.  Table 14 lists the number of
plants in each  subcategory  in  the  sample  according  to  what
operations  are conducted in the pl^nt.  The cutting operation is
conducted primarily in chicken plants so it is not  reported  for
the other subcategories.

The  raw  waste  load and related quantities of farther processed
products and rendering raw materials were analyz' 1  to  determine
whether  or not there was any relationship betwf n waste load and
further  processing  or  rendering.   There  wa   no   consistent
positive pattern between increasing volumes of  rurther processing
or rendering with a corresponding increase in raw waste  load.  In
fact,  most  of  the  plants with onsite rendering had lower than
average raw  waste  loads,  which  may  simply  indicate   a  more
                                53

-------
Table 13.  Raw Waste Characteristics for Further Processing Only
Parameter
Production
Waste Water
Flow
BOD5
SS
Grease
COD
TVS
TDS
TKN
NH3
N03
N02
Cl
TP
Units
kg /day FP
(Ib/day FP)

I/kg FP
(gal/lb FP)
kg/kkg FP
kg/kkg FP
kg/kkg FP
kg/kkg FP
kg/kkg FP
kg/kkg FP
kg/kkg FP
kg/kkg FP
kg/kkg FP
kg/kkg FP
kg/kkg FP
kg/kkg FP
Average
36,700
(80,500)

12.5
(1.50)
19.03
9.06
6.36
40.63
16.16
30.01
2.04
0.13
0.018
0.0019
2.25
0.12
Range
11,400 - 77,600

2.92 - 21.34
16.71 - 22.11
2.92 - 14.64
4.83 - 7.89
—
11.69 - 20.64
—
—
6.095 - 0.16
—
—
1.03 - 3.47
— -
Number of
Observations
4

4
3
3
3
1
2
1
1
2
1
1
1
1

-------
w
CC
UJ
H
-J
_l
O
>
cc
UJ
I-
120
115
110
105
100
 95
 90
 85
 80

 70
55
50

40
35
30
25
20
15
10
 5
 0
                 CHICKEN
                             TURKEY
FOWL
        Figure 4.  Average Waste Water Volume Generated Per Bird in
                   Processing Plants by Subcategory
                   [Further Processing Only is 12.5 liters/kg FP (1.5  gal/lb)]

-------
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(DATA PTS -
                                      Figure 5.  Average  Raw Waste Loading of Waste Water
                                                 From- PlriTits 'in Each Suhcattgory

-------
Table 14.
           The Number of Plants in the Questionnaire
           Sample Reporting the Use of Various
           Manufacturing Processes Within Each
           Subcategory
Manufacturing Process
Slaughter only
Slaughter plus cutting
Slaughter plus rendering
Slaughter plus further
processing
Slaughter plus cutting
plus rendering
Total
Chicken
19
38
5
7
21
90
Turkey
21
—
2
11
34
Fowl
4
—
2
2
8
Duck
4
1
—
—
5
                     57

-------
concerted effort at collecting and retaining byproducts or better
byproduct  materials  handling situations in those plants.  There
is some indication of increased waste load with ir^raased  output
of  further  processed  products  in poultry slaughtering plants.
However? it is not statistically significant.  Therefore, the raw
waste data are reported for all plants in each subcategory sample
and are included in the singular averages for the  subcategori^s.
These  averages  thus  include the plants tbct further process or
render in addition to slaughtering,

A regression analysis of the  raw  BOD5  loading  of  chicken  or
turkey plants that slaughter and further process as a function of
total  output  of further processing products yielded an es-timate
of the increase in raw waste BOD5 of 0.11 kg/kkg LWK per 1000  kg
FP  (0.05 lb/1000 113 LWK increase in BOD5 per 1000 Ib FP) .  There
are four plants in the sample producing U5,000 kg  (100,000 Ib) FP
or more in processing plants.  At this  level  of  production  of
further   processed  products,  the  results  of  the  regression
analysis suggests that the raw  BODji  waste  load  would  be  5.0
kg/k&g  LN'K  (5.0 lb/1000 Ib LWK) higher than if the plant did no
further processing, and only slaughtered.   This  result  is  not
statistically verifiable because of the wide scatter of the data,
but  the  information  can  be  incorporated  into  the  proposed
limitations as discussed in Sections IX through XI.

Data on the BOD5 loading of the raw waste water  for  each  month
during  one  or  two  years were obtained from eight plants.  The
analysis of these data revealed that in four of  the  plants  the
raw  waste  v/ater  loading  of  BOD?5 tended to be more stable and
consistent during the months  of  April  through  July.   A  more
persistent pattern of variability during the latter months of the
year  was  found  in  the  data  from  these  plants.   Generally
speakingr a waste loading range equal to two  times  the  typical
low  value  of  BOD5  would  include about 90 percent of the data
points for any given plant throughout the year.  There also  were
two  plants  with  very  consistent  raw waste loading during the
entire year, varying less than 30 percent above  the  average  in
one case.

A  statistical test was used to determine the existence of mutual
relationships between the  various  pollutant  parameters,  e.g.,
BOD5P suspended solids, grease, and the various nutrient sources.
Correlation  analysis  determines if increases in the quantity of
one  pollutant  in  a  waste  water  system  are  accompanied  by
corresponding increases or decreases of another pollutant.  There
is  a  considerable amount of data on broiler plants in the North
Star sample; however, the scattering of the data  resulted  in   a
finding  of  no  significant  correlation  or strong relationship
between any of the pollutant  parameters.   The  data  on  turkey
plants are far less extensive, however a significant relationship
was  found  between  BOD5  and suspended solids in the raw waste.
This relationship  is  one  of  the  expected  outcomes  of  this
analysis;   that  as  one  increases  the  other  also  increases
correspondingly.  It is wrong to conclude, however, that there is
                                58

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a  cause  and  effect  relationship  between  highly   correlated
variables such as these pollutant parameters.


                Process Waste Water Flow Diagrams

The  origin and estimate of relative process waste water quantity
is indicated for the two general poultry  production  processes--
dressing  and  further processing—in Figures 6 and 7,  The waste
water from cleanup, which is usually the  largest  and  strongest
waste  load  from further processing operations, is not indicated
in these figures because cleanup involves  virtually  the  entire
processing  plant,  with  the exception of the freezer areas, and
the cleanup waste water follows the same path through  the  plant
as a process waste water.

The  sources  and  relative  quantities  differ for each process.
However, byproduct recovery  with  rotary  or  vibrating  screens
followed  by  a  catch  basin is typical of dressing plants.  The
upstream screens  are  unnecessary  in  further  processing  only
plants; however, a catch basin is always desirable.  Screens were
also   installed   downstream  from  the  catch  basin  or  on  a
recirculating waste water stream from the catch basin  in  a  few
plants.

The other options available to the industry are also indicated in
these  figures.   The  plant  utilities  waste  water may by-pass
biological treatment.  The dilution and increased volume of waste
water only serves to inhibit biological treatment  effectiveness.
The sanitary sewage always enters the waste water downstream from
the catch basin.

Liquid  waste and wash water from the truck holding and unloading
areas is also handled in different ways by processing  plants  in
the  industry.   Most  segregate  the  entire  waste system while
others combine the waste water downstream from the in-plant catch
basin.  Also, most companies do not wash down  the  live  poultry
trucks on the plant site.
               WATER USE/WASTE LOAD RELATIONSHIPS

Increased  water  use  is  usually  associated with increased raw
waste loading from plants throughout the meat industry.  This  is
generally  true  for poultry processing plants also, and has been
demonstrated  in  experimental  programs  in   poultry   plants.9
However,  this  conclusion  is not substantiated as statistically
significant with the  data  from  the  different  plants  in  the
sample.   There  are  a  small number of poultry plants with high
water use and low waste load, and vice versa,  ana  these  plants
disturb  the rigorous statistical test of signifjcance.  However,
there is a trend that increased water use will  generally  result
in higher raw waste loads, as measured by BODjj.
                                59

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              PROCESSES
PRODUCT FLOW     I    BY-PRODUCT FLQW
                                       WASTE
                               LIQUID
SOLID
    BIRDS
                                     ALTERNATE SOLIDS I FLOW
                                            AS SOLIDS I WASTE
                                        (INCLUDES DRY I CLEANUP)
                           1NEWBLE  I  __
                          RENDERING
                                 J
   FRESH &
   FROZEN
   POULTRY
                                         SLUDGE  |
                       MATERIALS FLOW—
                       PROCESS WATER	
                       WASTE WATER	
                                         IOI.UL/UC
                                       |——	 1
                             (SECONDARY |   |   SOLID   j
                             I  TREATMENT •   I   WASTE
                             I    PLANT   I   I  DISPOSAL
                             I	1   I	I
                                   L_   DISCHARGE TO
                                        RECEIVING WATERS
     Fi gure  6.
Product and Waste jnfater  Flow for  Typical
Poultry Processing Plants
                         60

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              PROCESS AND MATERIAL FLOW
                                            WASTER WATER,
                                           RELATIVE FLOW*
                                                       i r
                     RECEIVING
                        AND
                     STORAGE
                                                         SM-PER ODIC
   CUT-UP
 OPERATIONS
                                                         SM-PERIODIC
                                                         MED-LGE

                                                         SM-MED PERIODIC
                          DICING.
                        GRINDING
                        CHOPPING
 BATTER AND
  BREADING
                                         MIXING,
                                        BLENDING
                                          SM - IVIED PERIODIC

                                          SM - MED
                                                             MED -LGE

                                                             MED -LGE
                          PREPARATION
              FREEZING &
              PACKAGING
                                          VSM PERIODIC
                                       MATERIAL OR
                                       PRODUCT FLOW
  COLD
STORAGE
                                       WASTE WATER
*VSM  -VERY SMALL
 SM    - SMALL
 MED  -MEDIUM
 LGE   - LARGE
                                        TO SECONDARY TREATMENT
                                       AND DISCHARGE OR CITY SEWER
       Figure  7.   Process and Waste Water Flow  For Further Processing
                                61

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The  trend  lines  of  waste  load  versus waste water volume for
chicken  and  turkey  plants  are  presented  in  Figure  8.    An
interpretation  of  these  trend  lines  suggests that in chicken
plants, a 25-percent reduction in water use from, say, 45  to  35
liters  per bird (11 to 9 gallons per bird) would result in a 15-
percent reduction in the raw BODji waste load.  In turkey  plants,
a 39-percent reduction in water use would reduce the BOD5 loading
by  about  15  percent in the raw waste.  Each plant probably has
its own typical and unique  water  use/waste  load  relationship,
although it may differ somewhat from Figure 8.

Basically,  low  water use and the correspondingly low waste load
require attentive and concerned  management  attitudes  regarding
in-plant  water use.  Without the active support and intervention
of management, water management programs do not succeed; with it,
water use can be reduced and the raw waste  load  will  decrease.
Waste  water  treatment  systems  operate  more  effectively with
reduced hydraulic and waste loads.


              SOURCES OF HASTE WATER AND WASTE LOAD

                      Killing and Bleeding

The strongest single pollutant in a  poultry  dressing  plant  is
blood.   Chicken blood has an approximate BOD5 of 92,000 mg/1 and
1,000  chickens  may  generate  7,9  kg  (17.4  lb)   of  BODji  in
recoverabls  blood.9  Poultry are manually or mechanically killed
by an exterior cut on the neck; ducks may be killed by  inserting
a  knife  rinto  the  mouth and down the throat, thus avoiding the
exterior cut.  The common practice is to  electrically  stun  the
birds  just  before  killing.  Occasionally, stunning follows the
kill, and in a few plants other measures  are  employed  such  as
ultraviolet lighting instead of an electric shock.

The  birds  are bled while they hang from a moving conveyor.   The
conveyor is confined to a single rbpm or space usually called the
blood tunne.L, which is equipped with some means of collecting and
handling the blood.  A couple of plants have installed  a  raised
metal  trough  to  collect and retain the blood as the birds were
convened along the length of it.  This trough  is  installed  and
operated  primarily  as  a  byproduct recovery device.  It is dry
cleaned with a squeegee several times  during  the  day  and  the
blood flows through a vacuum line to a holding tank.

There  are  three factors that control the quantity of blood that
enters the waste water stream:  time in the  blood  tunnel,  body
movement  of  the  birds  in the tunnel, and handling and cleanup
procedures for the blood.  The residence time of an animal in the
blood tunned is fairly  well  standardized  across  the  industry
today.   However,  those  few  plants that were found to maintain
shorter bleed times demonstrated unusually high raw waste  loads.
This  presumably  results  from  latger volumes of residual blood
draining after removal of the animal from the blood tunnel.
                                62

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a-
                   20
                    18
                    16
                    14
                D)
*&  12
 ih
§   10
DO
LU
w   8
5

I   6
cc
    4
                                    WASTE WATER VOLUME FOR CHICKEN PLANTS, GALS/BIRD
                              2   3   4   5   6   7   8  9   10 11  12  13  14 15  16  17  18
                                                 CHICKEN
                                                 PLANT
                                                 DATA
                                                              /I TURKEY
                                                              M PLANT
                                                                 I DATA
                           5   10  15  20  25  30   35  40  45  50 55  60  65  70  75  80  85  90
                                  WASTE WATER VOLUME FOR TURKEY PLANTS, GALS/BIRD

                     Figure 8.   Approximate  Relationship Between Raw Waste Loading of BOD5 and
                                Waste Water  Volume Per Bird for Chicken and Turkey Plants

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Body movement of the birds as they bleed may  scatter  the  blood
onto the feathers of adjacent birds and onto the conveyor and the
walls  of  the  blood  tunnel.  The blood on the feathers will be
washed off in the scalder and into the waste water.  The blood on
the conveyor and walls will be washed off into the  sewer  during
cleanup.,

Handling  and  cleanup procedures can contribute significantly to
the quantity of blood that is allowed to enter  the  sewer.   The
metal  trough  described  previously was a particularly effective
mechanism for confining and handling blood.  No plants were found
to dump i:he blood into the sewer.  It is a valuable byproduct and
is handled as such.  However, large  bleeding  spaces  and  heavy
reliance  on  water  washing  in  preference  to  dry cleanup add
significantly to the waste load,


                            Scalding

The scalding operation loosens the body feathers of poultry.   It
is  also  the  first  washing  of the carcasses, thus the scalder
effluent will contain dirtff feathers,  fclood,  manure,  and  some
dissolved  fats  and  greases.  The TJSDA requires an overflow and
freshwater makeup of one-quarter gallon per bird.  The BOD5 in  a
scalder  has  been measured at 490 mg/1 and 1,182 mg/1, suspended
solids at U73 and 687 mg/1, and grease at 350 mg/1.9

The scalder overflow is usually used to augment the feather  flow
away  water  and  is dumped directly into the feather flume.  The
scalder water is maintained at temperatures between 53° and  63°C
(128°  and  1U5°F);  however, the flow is not sufficient to raise
the waste water temperature much above 21°C  (70°F).  The  primary
impact of ttie scalder occurs at the end of the operating day when
it  is  dumped  and  cleaned.   The dumping generates a potential
shock load i;o the waste water handling system.  Cleanup  requires
washing  the  dirt,  blood, and other accumulated debris from the
scalder and into the sewer again in relative surges of water.


                          Defeathering

Large quantities of water are used  to  move  feathers  from  the
defeathering   operation   to  byproduct  recovery  in  flow-away
systems.  This water use has been estimated to total 10.6  liters
(2,8  gallons)  per bird in a chicken plant, including 50-percent
freshwater  c.nd  50  percent  reused   or   recirculated   water.
Defeathering  water  will  contain  dirt  and blood and feathers.
Screened offal flume water also is sometimes  reused  in  feather
flumes.  The BODjj in a feather flume was reported to be 590 mg/1,
the  suspended  solids 512 mg/1, and grease 120 mg/1.9  The North
Star waste water sampling  program  obtained  these  results  for
feather  flume  waters:  565  mg/1  BODji  and  330 mg/1 suspended
solids.  The feather flume was also reported to be a high  source
of  ammonia,,  on  the  order of seven times higher than the offal
flume**°

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A carcass washer follows the defeather process.   The  water  use
rate  in  this washer was found to be 140 liters/min (37 gpm)  and
the BOD5 of the waste water was reported to  be  108  mg/1,  with
suspended solids of 81 mg/1 and grease at 150 mg/1,9

Cleanup  of  the defeathering area occurs periodically during the
day and at the end of the day, usually involving the use of large
quantities of water to wash the feathers  into  the  flume.   The
water  use  was  found  to be 130 liters/min  (34 gpm) during this
intermittent cleaning at one plant.9


                          Evisceration

The evisceration process generates a large volume of waste water.
Carcass and giblet washing, worker hand washers, side-pan washers
in the viscera trough, and viscera flow-away water all contribute
to the total evisceration waste water which has been estimated to
be 23 liters  (6.1 gallons) per bird.9

In the evisceration process, the bird is opened up,  the  viscera
are  extracted  from the peritoneal cavity; after inspection, the
giblets are removed from the viscera, then  trimmed  and  washed;
and  the  inedible  viscera  is  dropped into the viscera trough.
Heads and feet are removed from the birds and  dropped  into  the
feather  or  offal  flumes.   The lungs are usually vacuumed to  a
holding tank, and the windpipe and extraneous tissue are  removed
and  dropped into the trough.  A carcass washer is located at the
end of the evisceration line to wash both the inside and  outside
of the birds.  In one plant, this washer used 380 liters/min  (100
gpm) or about 3 liters  (0.8 gallons) per bird.9

Much  of  the  eviscerating process is done by hand.  The workers
and inspector are required to use hand washers  to  avoid  cross-
contamination.   The  quantity  of  water  used  in  hand washing
appears to be discretionary.

The waste water from evisceration will  contain  tissue  and  fat
solids,  grit,  grease,  blood,  and bacteria from the intestinal
tract,  A BODj> of 230 mg/1 and suspended solids of 302  mg/1  are
reported   in   the  literature.9   This  BOD5  concentration  is
equivalent to about 5.4 kg  (12 Ib)  per  1,000  broilers.   North
Star  sampled  an offal flume downstream from the offal screening
equipment and found a BOD5 of 365 in 7/1 and  suspended  solids  of
196 .Tig/1.

Cleanup  of  the  evisceration  line  also consumes a significant
volume of water, although  the  waste  loading  i~5  comparatively
light.   The  equipment  is washed down at every break and during
the lunch hour, and then it is thoroughly cleaned at the  end  of
the  day.   The cleanup waste load consists primarily of meat and
fat particles left clinging to the equipment, the grease  coating
that  accumulates  on  exposed surfaces, and residual solids that
were not conveyed by the flow-away system in the trough.


                                65

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                            Chilling

The temperature of the carcass and giblets  of  poultry  must  be
quick3,y  reduced to 4°C  (40°F) after evisceration.  The carcasses
are usually cooled by immersion in two-stage chillers filled with
ice-water„  The USDA  requires  that  1.9  liters   (0.5  gal)  of
freshwater  nust  be  added  per bird.  An overflow, equal to the
make-up; plus dragout losses results in about  2.8  liters   (0.75
gal)   per  bird of waste water into the sewer, frequently via the
offal flume.   Giblets  are  cooled  in  smaller  but  comparable
equipment or in heat exchangers which prevent contact between the
cooling water and the giblets.

The  waste  water  from  carcass  chillers  was  found  to be 272
liters>'ttin  (72 gpmj for a plant processing 70,000 birds  per  day
and  the  giblet chillers used 17 liters/min  (U.5 gpm). *  The raw
waste load of BOD5 in giblet chilling water was  reported  to  be
2,357 mg/lt, with suspended solids at 976 mg/1 and grease at 1,320
mg/1.9  The exceptionally high concentrations may result from the
low water volume.  The carcass chiller waste load was reported to
be  i*<&0  mg/1  and  320  mg/1  of  BODji from the first and second
chillers,, respectively.  The suspended solids were  found  to  be
250  mg/J.   and 180 mg/1 and grease was 800 mg/1 and 250 mg/1 for
the waste water from the first and second chillers,  A North Star
sample ol chiller water in a turkey plant  was  analyzed  at  180
mg/1 BOD5 and 77 mg/1 for suspended solids.

Cleanup  of  the chilling equipment requires dumping the water at
the end of each day, which may overload the waste water  handling
system  if  dumped  over  a  short period of time.  The equipment
acquires .1 conspicuous covering of grease  which  is  washed  off
during  cleanup.  This material is wasted to the sewer.  Meat and
fat particles and blood accumulate  in  the  chiller  during  the
operating  day.   Any materials remaining in the chiller after it
has been clumped are washed out during cleanup,


                       Byproduct Recovery

The screening equipment for the feather and offal flumes and  the
byproduct  material  handling  equipment  comprise  the byproduct
recovery area.  No appreciable amount of waste water is generated
in byproduct recovery other than the screen  washing  water  used
during  the  operating day and the water from cleanup.  The water
retained by  the  feathers  and  offal  will  drain  through  the
materials  handling  equipment  and  from  the  offal truck which
receives and holds these byproducts  throughout  the  day.   This
drainage enters the waste water stream directly,

The  waste  load  is not generated per se, in byproduct recovery,
but results from losses due to inefficiency or ineffectiveness of
the recovery equipment.  Thus? although the waste water  quantity
generated  in  byproduct recovery is small, the waste load may be
substantial, depending on the screening effectiveness in removing
                                 66

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offal and feathers and the manner in which the blood  is  handled
on the offal truck.  If blood is simply dumped on the feathers or
the  offal,  it  will  3rain through and add significantly to the
waste load.
                       Further Processing

Further processing  operations  use  water  to  thaw  frozen  raw
materials,  e.g., turkeys, to cook poultry and finished products,
to cool the freshly cooked birds and products, and to  clean  the
plant and equipment.

When  frozen birds are used as a source of raw materials, further
processing operations thaw the birds in chillers—otherwise  used
to  chill  freshly  eviscerated  birds—or in large portable vats
filled with water and agitated by bubbling air through the water.
The frozen birds are thawed while wrapped in a protective package
such as Cry-O-Vac, or are unwrapped prior  to  thawing.   If  the
former  is used, the water does not contact the birds directly as
it would in the latter case, and  the  waste  load  from  thawing
would be relatively little.  The direct contact between the birds
and  water  results  in  a  significant waste load in the thawing
waters.  These waters are dumped after each  batch  of  birds  is
thawed,  with  the  resulting  water  and waste load entering the
sewer.

Birds and finished products are frequently cooked by immersion in
steam-jacketed vats of hot water.  Baskets  of  whole  birds  and
parts  or  racks of products are immersed in the hot water, which
includes spices and preservatives.  The grease  from  cooking  is
continuously  collected  as  a  high-value edible fat.  The total
volume of waste  water  is  relatively  small.   It  amounted  to
approximately 0.1 liters  (p.03 gallons) per processed bird in one
plant sampled by North Star.  The waste load in one sample of the
cooking waters at the same plant was found to be 4,665 mg/1 BOD5,
1,068 mg/1 suspended solids, and 514 mg/1 grease.  These vats are
dumped  at the end of each processing day and thoroughly cleaned.
While the waste water volume is not great, the waste  load  is  a
significant one.

Many  of  the  freshly  cooked products are immediately cooled by
immersion in cold  water.   Cooling  tanks  are  similar  to  the
cooking  vats,  but  without a steam jacket.  A cold water makeup
and subsequent overflow is required at between 2 and 4 liters per
minute  (0.5 and 1 gpm).  The cooling water is fresh* clear  water
without any processing additives.  However, the wat^r in the tank
comes  into  immediate  contact with the hot produc .s and chicken
parts.   These  cooked  products  and  chicken   p rts   have   a
substantial surface coating of various pollutants  such as grease,
cooking  water  and broth, and spices and preserv ^tives.  Most of
these materials plus seme meat, fat, and skin tissue  are  washed
into the cooling water.  The overflow from the cooling tank flows
into  the sewer during the operating day.  At the end of the day,
the tank is emptied and cleaned.  The volume of water  discharged
                                 67

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at this time is relatively small; however, the accumulated solids
and  other  pollutants  are  dumped,  simultaneously generating a
considerable waste load.
         Rendering Plant condensate and Condenser Water

Some poultry processing plants have onsite  rendering  plants  to
produce  feed  grade  materials  from  the  byproducts (feathers,
offalp blood, etc.) of the processing plant.  A small  number  of
plants  have sufficient rendering capacity to bring in byproducts
from other dressing plants.

Condensate from cooking and drying  the  byproducts  is  a  high-
strength  waste.   A  previous study of the independent rendering
industry provided data indicating BOD5 concentrations of 1,235 to
1,350  mg/1  in  undiluted  condensate  from  poultry   byproduct
rendering.   The  suspended solids and grease are inconsequential
in the condensate.  Undiluted condensate would occur  only  in  a
closed  condenser  such  as  air  or  shell-and-tube  condensers.
Barometric condensers will dilute the condensate  and  lower  the
concentration,  but  the total loading of the rendering raw waste
is unaffected.

Spills from the rendering equipment and materials  handling  will
contribute  to  the raw waste load.  Cleanup of these spills will
add to the waste water volume.

The waste w;\ter generated in onsite rendering systems amounts  to
about  15,800 1/kkg raw material  (1,900 gal per 1000 lb RM) based
on the data collected by North Star.  For  chickens,  this  waste
water  flow  is  equivalent  to  approximately  7.2  liters   (1.9
gallons) per bird,  and  for  turkeys  it  is  27.6  liters   (7.3
gallons)  per bird, or 20 and 23 percent of the average flow from
chicken and turkey dressing plants, respectively.
                                 68

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                           SECTION VI

                SELECTION OF POLLUTANT PARAMETERS


                       SELECTED PARAMETERS

Based on a review of the Cofps of Engineers1 Permit  Applications
from poultry processing plants; previous studies on similar waste
waters  such  as  from  the  meat  packing,  meat processing, and
independent rendering plants; industry data; questionnaire  data;
and  data  obtained  from sampling plant waste waters during this
study,  the  following   chemical,   physical,   and   biological
constituents constitute pollutants as defined in the Act.

     BOD5 (5-day, 20°C biochemical oxygen demand)

     COD  (chemical oxygen demand)

     Suspended solids  (TSS)

     Total dissolved solids  (TDS)

     Total volatile solids  (TVS)

     Grease

     Ammonia nitrogen

     Kjeldahl nitrogen

     Nitrates and nitrites

     Phosphorus

     Chloride

     Bacteriological counts  (total and fecal coliform)

     PH

     Temperature

On  the   basis  of  all evidence reviewed, there do not  exist any
purely hazardous pollutants  (such as heavy metals or  pesticides)
in the waste discharge from  poultry processing plants.

        RATIONALE FOR SELECTION OF IDENTIFIED PARAMETERS

             5-Pay Biochemical Oxygen Demand  (BODS)

This  parameter is an important measure of the oxy-jen consumed  by
microorganisms in the aerobic decomposition of the wastes at 20°C
over a five-day period.  More simply, it is an   indirect measure
of  the   biodegradability of the organic pollutants in the waste.


                                69

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   ^ can be related to the depletion of oxygen in  the  receiving
stream or to the requirements for the waste treatment.  Values of
BOD5  range  from  100  to  1500  mg/1 in the raw waste, although
typical values range from 200 to 700 mg/1.

If the BOD^ of the final effluent of a poultry  processing  plant
into  a  receiving body is too high, it will reduce the dissolved
oxygen level Ln that stream to below a level  that  will  sustain
most  fish life; i.e., below about 4 mg/1.  Many States currently
restrict the BOD5 effluents to below 20 mg/1  if  the  stream  is
small  in comparison with the flow of the effluent.  A limitation
of 200 to 300 mg/1 of BOD5 is often applied for  discharge  to  a
municipal  sewer,  and surcharge rates often apply if the BOD5 is
above the designated limit.  BOD^ is  included  in  the  effluent
limitations  recommended  because  its  discharge  to a stream is
harmful to aquatic life since it depletes the oxygen supply.

A 20-day biochemical  oxygen  demand  (BOD20),  sometimes  called
"ultimate-1  BOD,  is  usually  a better measure of the waste load
than BOD5>.   However, the test for BOD20 requires 20 days to  run,
so it is an impractical measure for most purposes.

Correlation  analysis  of  the  data  revealed  a  high  positive
correlation between BOD5 and suspended  solids,  chemical  oxygen
demand,  total  volatile  solids,  Kjeldahl nitrogen, and ammonia
nitrogen on both the raw and final effluent.   Such  correlations
are  useful in identifying contributing factors in the waste load
and relating  known  changes  in  the  contaminant  to  predicted
changes by another.


Biochemical  oxygen  demand  (BOD)   is  a  measure  of the oxygen
consuming capabilities of organic matter.  The BOD  does  not  in
itself  cause direct harm to a water system, but it does exert an
indirect effect by depressing the oxygen content  of  the  water.
Sewage  and  other  organic  effluents  during their processes of
decomposition exert a BOD, which can have a  catastrophic  effect
on  the ecosystem by depleting the oxygen supply.  Conditions are
reached frequently where all  of  the  oxygen  is  used  and  the
continuing  decay  process causes the production of noxious gases
such as hydrogen sulfide and methane.   Water  with  a  high  BOD
indicates   the   presence  of  decomposing  organic  matter  and
subsequent high bacterial counts that  degrade  its  quality  and
potential uses.

Dissolved  oxygen  (DO)  is  a water quality constituent that, in
appropriate  concentrations,  is  essential  not  only  to   keep
organisms living but also to sustain species reproduction, vigor,
and  the development of populations.  Organisms undergo stress at
reduced DO concentrations that make  them  less  competitive  and
less   able   to   sustain   theit-  species  within  the  aquatic
environment.  For example, reduced DO  concentrations  have  been
shown  to interfere with fish population through delayed hatching
of eggs,  reduced  size  and  vigor  of  embryos,  production  of
deformities   in   young,   interference   with  food  digestion.
                                70

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acceleration of blood clotting, decreased  tolerance  to  certain
toxicants,  reduced  food efficiency and growth rate, and reduced
maximum  sustained  swimming  speed.   Fish  food  organisms  are
likewise  affected  adversely  in  conditions with suppressed DO.
Since all aerobic aquatic organisms  need  a  certain  amount  of
oxygen, the consequences of total lack of dissolved oxygen flue to
a high BOD can kill all inhabitants of the affected area.

If  a  high  BOD  is present, the quality of the water is usually
visually degraded by the presence of  decomposing  materials  and
algae  blooms,  due to the uptake of degraded materials that form
the foodstuffs of the algal populations.


                  Chemical Oxygen Demand (COP)

COD is yet another measure of oxygen  demand.   It  measures  the
amount  of  organic  (and  some  inorganic)  pollutants  under  a
carefully controlled, direct chemical oxidation by a  dichromate-
sulfuric  acid  reagent.   COD  is  a  much more rapid measure of
oxygen  demand  than  BODj>,  and  is  potentially  very   useful.
However,  it  does  not  have  the  same significance, and at the
present time cannot be substituted  for  BOD5,  because  COD:BOD^
ratios vary with the types of wastes.  The COD measures more than
only those materials that will readily biodegrade in a stream and
hence  deplete  the  stream's  dissolved  oxygen supply.  The COD
range for poultry processing plants is from 100 to 2,800 mg/1  in
the raw waste.

COD  provides  a  rapid determination of the waste strength.  Its
measurement  will  indicate  a   serious   plant   or   treatment
malfunction  long  before  the BODI5 can be run.  A given plant or
waste treatment system usually has a relatively narrow  range  of
COD:BODj>   ratios,   if  the  waste  characteristics  are  fairly
constant, so experience permits a judgment to be made  concerning
plant  operation  from  COD  values.   In  the poultry processing
industry, COD ranges from about 1. 0 to 6 times the BOD5.  in  both
the raw and treatment wastes, with typical ratios between 1.5 and
3.0.   Although  the  nature  of  the  impact of COD on receiving
waters is the same as the BOD.5, BQDJ5 was chosen for inclusion  in
the   effluent   limitations  rather  than  COD  because  of  the
industry's  frequent  use  and  familiarity   with   BOD5.    COD
correlates  with  BOD5 and suspended solids  (TSS) in both the raw
and final effluent, although the CODrTSS correlation  is  not  as
good in the final as the raw.


                     Suspended Solids  (TSS)

This  parameter  measures  the  suspended  material  that  can be
removed from the waste waters by laboratory filtration, 'but  does
not  include  coarse  or  floating matter that can be screened or
settled out readily.  Suspended solids are a  visual  and  easily
determined  measure  of  pollution  and  also  a  measure  of the
material that may settle in tranquil or slow-moving  streams.   A


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high  level  of  suspended  solids is an indication of high
Generally, suspended solids range from cne-third to three-fourths
of the BODj> values in the raw waste.  Suspended solids are also a
measure of the effectiveness of solids removal  systems  such  as
clarifiers and fine screens,

Suspended  solids  frequently  become  a limiting factor in waste
treatment when the BOD5 is less than about 20 mg/1.  In fact,  in
highly  treated  waste,  suspended  solids  usually have a higher
value than the BODfS and in this case, it may Jbe easier  to  lower
the  BOD5 even further^ perhaps to 5 to 10 mg/1, by filtering out
the suspended solids.  TSS in the raw waste  water  from  poultry
processing  plants range from 75 to 1,100 mg/1.  Suspended solids
in -the raw and treated waste waters of poultry processing  plants
correlate well with BOD5, COD, and total volatile solids,

Suspended  solids  in  receiving  waters  act  as a substrate for
bacterial population.  The substrate acts as  adsorption  surface
for   ionic  nutrients,  thus  resulting  in  high  BOD5  values.
Suspended: solids  also  inhibit  light  penetration  and  thereby
reduce   the  primary  productivity  of  algae  (photosynthesis).
Because of  the  strong  impact  suspended  solids  can  have  on
receiving  waters, suspended solids were included in the effluent
limitations reported in this report.


Suspended solids include both organic  and  inorganic  materials.
The  inorganic  components  include  sand,  silt,  and clay.  The
organic fraction includes such materials  as  grease,  oil,  tar,
animal  and  vegetable  fats,  various fibers, sawdust, hair, and
various materials from  sewers.   These  solids  may  settle  out
rapidly  and  bottom deposits are often a mixture of both organic
and  inorganic  solids.   They  adversely  affect  fisheries   by
covering  the  bottom  of  the  stream  or lake with a blanket of
material that destroys the fish-food bottom fauna or the spawning
ground  of  fish.   Deposits  containing  organic  materials  may
deplete  bottom  oxygen  supplies  and  produce hydrogen sulfide,
carbon dioxide^ methane, and other noxious gases.

In raw  watar  sources  for  domestic  use.  State  and  regional
agencies generally specify that suspended solids in streams shall
not be present in sufficient concentration to be objectionable or
to  interfere  with normal treatment processes.  Suspended solids
in water may interfere with many industrial processes, and  cause
foaming  in  boilers,  or  encrustations  on equipment exposed to
waterp especially as the temperature rises.  Suspended solids are
undesirable in water for  textile  industries;  paper  and  pulp;
beverages;   dairy   products;  laundries;  dyeing;  photography;
cooling systems, and  power  plants.   Suspended  particles  also
serve   as   a  transport  mechanism  for  pesticides  and  other
substances which are readily sorbed into or onto clay particles.

Solids may be suspended in water for a time, and then  settle  to
the   bed  of  the  stream  or  lake.   These  settleable  solids
discharged with man's wastes may be inert?  slowly  biodegradable
                                72

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materials,   or   rapidly   decomposable  substances.    While  in
suspension, they increase the  turbidity  of  the  water,   reduce
light  penetration  and  impair  the  photosynthetic  activity of
aquatic plants.

Solids in suspension are aesthetically  displeasing.   When  they
settle  to  form  sludge deposits on the stream or lake bed, they
are often much more damaging to  the  life  in  water,  and  tiiey
retain  the  capacity  to  displease  the  senses.   Solids, when
transformed to sludge deposits, may  do  a  variety  of  damaging
things,  including  blanketing the stream or lake bed and thereby
destroying the living spaces for  those  benthic  organisms  that
would  otherwise  occupy  the  habitat.   When  of an organic and
therefore decomposable nature, solids use a portion or all of the
dissolved oxygen available in the area.  Organic  materials  also
serve  as  a  seemingly inexhaustible food source for sludgeworms
and associated organisms.

Turbidity  is  principally  a  measure  of  the   light-absorbing
properties  of  suspended  solids.   It  is  frequently used as a
substitute method  of  quickly  estimating  the  total  suspended
solids when the concentration is relatively low.
                  Total Dissolved Solids (TDS)

The  total  dissolved  solids in the waste waters of most poultry
processing plants contain mainly inorganic salts.  The amount  of
dissolved  solids  will vary with the type of in-plant operations
and the housekeeping practices.   Total  dissolved  solids  range
from  170  to  2,300  mg/1  in  the  raw  waste waters of poultry
processing plants.  Dissolved solids are of  the  same  order  of
magnitude  and  correlate  well with the total volatile solids in
the raw waste waters, implying that,  in  general,  much  of  the
dissolved  solids  are  volatile.  The inorganic dissolved solids
are particularly important because they are relatively unaffected
by biological treatment processes.   Therefore,  unless  removed,
they will accumulate within the water system on total recycle, or
reuse,  or  build up to high levels with partial recycle or reuse
of  the  waste  water.   Another  salt   sometimes   present   in
significant quantities is sulfate.  This may come from sulfate in
the  incoming  raw  water,  or  perhaps  from  water conditioning
treatment of the  water  supply.   Sulfates  become  particularly
troublesome in causing odor in anaerobic treatment systems, where
they are converted to sulfides.

Dissolved  solids affect the ionic nature of receiving waters and
are usually the nutrients for  bacteria  and  protozoans.   Thus,
they  increase  the  eutrophication rate of the r  jeiving bo£y of
water.  Total dissolved solids were not included  .n the  effluent
limitations  recommended  in  this  report  becai.se  the  organic
portion would be limited by BODj>  limitations  and  the  nutrient
portion by the nitrogen and phosphorus limitations.
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In   natural  waters  the  dissolved  solids  consist  mainly  of
carbonates,  chlorides,  sulfates,   phosphates,   and   possibly
nitrates  of  calcium,  magnesium,  sodium,  and  potassium, with
traces of iron, manganese, and other substances.

Many communities in the United States and in other countries  use
w-iter supplies containing 2,000 to 4,000 ing/1 of dissolved salts,
wii^n   no  better  water  is  available.   Such  waters  are  not
palatable, may not quench thirst, and may have a laxative  action
on  new  users.   Waters containing more than 4,000 mg/1 of total
salts are generally considered linfit for human use,  although  in
hot  climates  such  higher  salt concentrations can be tolerated
whereas  they  could  not  be  in  temperate  climates.    Waters
containing  5,000  mg/1 or more are reported to be bitter and act
as bladder and intestinal irritants.  It is generally agreed that
the salt concentration of good, palatable water should not exceed
500 mg/1.

Limiting concentrations of dissolved solids for  freshwater  fish
may  range  from  5,000  to 10,0^0 mg/1, according to species and
prior acclimatization.  Some fish are adapted to living  in  more
saline  waters,  and  a few species of freshwater forms have been
^ound in natural waters with a salt concentration  of  15,000  to
20,000  mg/1.   Fish  can  slowly  become  acclimatized to higher
salinities, but fish in waters of  low  salinity  cannot  survive
sudden  exposure to high salinities, such as those resulting from
discharges of oil well brines.  Dissolved  solids  may  influence
the  toxicity  of  heavy metals and organic compounds to fish and
other aquatic life, primarily because of the antagonistic  effect
of hardness on metals.

Waters  with total dissolved solids over 500 mg/1 have decreasing
utility as irrigation water.  At 5,000 mg/1 water has  little  or
no value for irrigation.

Dissolved  solids  in  industrial  waters  can  cause  foaming in
boilers and cause interference with the purity, color,  or  taste
of  many  finished  products.   High contents of dissolved solids
also tend to accelerate corrosion.:

Specific conductance is a measure bf the  capacity  of  water  to
convey  an  electric  current.   This  property is related to the
total concentration of ionized  substances  in  water  and  water
temperature.   This  property  is frequently used as a substitute
method of quickly estimating the dissolved solids concentration.


                   Total Volatile Solids  (TVS)

Total volatile solids is a rough measure of the amount of organic
matter in  the  waste  water.   Actually  it  is  the  amount  of
combustible material in both the total dissolved solids and total
suspended  solids.  Total volatile solids in the raw waste waters
of poultry processing plants range from 175 to  2,400 mg/1.  Total
volatile solids in the raw waste  waters  of  poultry  processing
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plants  correlate well with BOD5, TSS, total dissolved solids and
COD; total volatile solids in the final  waste  waters  correlate
well  with  BOD5  and  TSS.   Because  of  these correlations and
because total volatile solids is a relatively easy  parameter  to
determine,  it  could  be  used  as a rapid method to determine a
serious plant or treatment system malfunction.

Volatile solids in receiving waters are food for  microorganisms,
and thus increase eutrophication.  Effluent limitations for total
volatile  solids were not established because 1VS will be limited
by limitations on other pollutant parameters  such  as  BOD5  and
suspended solids.
                             Grease

Grease,  also  called  oil  and  grease, or hexane solubles, is a
major pollutant in the raw waste  stream  of  poultry  processing
plants.   Grease  forms  unsightly  films  and  layers  on water,
interferes with aquatic life, clogs sewers,  disturbs  biological
processes  in sewage treatment plants, and can also become a fire
hazard.  Hence effluent limitations were established for  grease.
The  concentration  of  grease  in  poultry processing raw wastes
varies from 100 to 400 mg/1.

Grease  may  foul  municipal  treatment  facilities,   especially
trickling  flitersp  and  seriously  reduce  their effectiveness.
Thus, it may be  of  great  interest  and  concern  to  municipal
treatment plants.


Oil  and  grease  exhibit  an  oxygen  demand.  Oil emulsions may
adhere to the gills of fish or coat and destroy  algae  or  other
plankton.  Deposition of oil in the bottom sediments can serve to
inhibit  normal  benthic  growths,  thus interrupting the aquatic
food chain.  Soluble and emulsified material ingested by fish may
taint the flavor of the fish flesh.  Water-soluble components may
exert toxic action on fish.  Floating  oil  may  reduce  the  re-
aeration  of the water surface and in conjunction with emulsified
oil   may   interfere   with   photosynthesis.    Water-insoluble
components  damage  the  plumage  and  coats of water animals and
fowls.  Oil and grease in a water can result in the formation  of
objectionable   surface  slicks  preventing  the  full  aesthetic
enjoyment of the water.

Oil spills can damage the surface of boats and  can  destroy  the
aesthetic characteristics of beaches and shorelines
                        Ammonia Nitrogen

Ammonia nitrogen is just one of many forms of nitrogen in a waste
stream.   Anaerobic  decomposition  of  protein,  which  contains
organic nitrogen, leads  to  the  formation  of  ammonia.   Thus,
anaerobic  lagoons  or  digesters produce high levels of ammonia.
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Also, septic  (anaerobic) conditions within the  plant  in  traps,
basins, etc., may lead to ammonia in the waste water.

Ammonia  is  oxidized by bacteria into nitrites and nitrates by a
process called "nitrification." This  may  occur  in  an  aerobic
treatment  process  and  in a stream.  Thus, ammonia will deplete
the oxygen  supply  in  a  stream;  its  oxidation  products  are
recognized nutrients for aquatic growth.  Also, free ammonia in a
stream is known to be harmful to fish.

Typical concentrations in the raw waste range from 1 to 100 mg/1;
however,   after   treatment   in   an   anaerobic   system,  the
concentrations of ammonia can reach 100 to 500 mg/1.  Ammonia  is
limited in drinking water to 0.05 to 0.1 mg/1.11  In some cases a
stream  limitation is less than 2 mg/1.  Effluent limitations for
1983 were established for ammonia because of the strong impact it
can have on receiving waters.


Ammonia is a common  product  of  the  decomposition  of  organic
matter.   Doad  and  decaying animals and plants along with human
and animal body wastes account for much of the  ammonia  entering
the  aquatic:  ecosystem.   Ammonia exists in its non-ionized form
only at higher pH levels and is the most  toxic  in  this  State.
The  lower  the  pH,  the  more ionized ammonia is formed and its
toxicity  decreases.   Ammonia,  in  the  presence  of  dissolved
oxygen,  is  converted  to  nitrate  (NO3J by nitrifying bacteria.
Nitrite (NQ2) , which is an intermediate product  between  ammonia
and  nitrate,  sometimes occurs in quantity when depressed oxygen
conditions permit.  Ammonia can exist in several  other  chemical
combinations including ammonium chloride and other salts.

In  mc-st  natural  water  the pH range is such that ammonium ions
(NH^t*)   predominate.    In   alkaline   waters,   however,   high
concentrations  of  un-ionized  ammonia in undissociated ammonium
hydroxide increase the toxicity of ammonia solutions.  In streams
polluted with sewage, up to one  half  of  the  nitrogen  in  the
sewage  may  i:e in the form of free ammonia, and sewage may carry
up to 35 mg/1 of total nitrogen.  It has been  shown  that  at  a
level  of  1.0 mg/1 un-ionized ammonia, the ability of hemoglobin
to combine with  oxygen  is  impaired  and  fish  may  suffocate.
Evidence  indicates  that  ammonia  exerts  a  considerable toxic
effect on all aquatic life within a range of less than  1.0  mg/1
to  25  mg/1,  depending  on  the  pH  and dissolved oxygen level
present.

Ammonia can add to the problem  of  eutrophication  by  supplying
nitrogen  through  its  breakdown products.  Some lakes in warmer
climates, and ethers that are aging quickly are sometimes limited
by the nitrogen available.  Any increase will speed up the  plant
growth and decay process.
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                        Kleldahl Nitrocten

This  parameter  measures  the  amount  of  ammonia  and  organic
nitrogen;  when used in conjunction with the ammonia nitrogen, the
organic nitrogen can be  determined  by  thf  difference.    Under
septic  conditions,  organic nitrogen decomposes to form ammonia.
Kjeldahl nitrogen is a good indicator of the crude protein in the
effluent and, hence, of the value of proteinaceous material being
lost in the waste water.  The protein content is usually taken as
6.25  times  the  organic  nitrogen.   the  sources  of  Kjeldahl
nitrogen  are  basically the same as f6r ammonia nitrogen, above.
The raw waste loading of Kjeldahl nitrogen is extremely  variable
and  is highly affected by blood loss to the waste waters such as
by  drainage  from   byproduct   trucks.    Typical   raw   waste
concentrations  of Kjeldahl nitrogen are between 50 and 100 mg/1.
Kjeldahl nitrogen has not been a common parameter for  regulation
and  is a much more useful parameter for raw waste than for final
ef f luent.    Even  so,  ef fluent   li mit a ti on s   for   1983   were
established for Kjeldahl nitrogen because, in addition to ammonia
which  has  a strong environmental impact on receiving waters, it
can be a major source of organic  material,  which  is  food  for
microorganisms in receiving waters.

                      Nitrates and Nitrites

Nitrates  and nitrites, normally reported as N, are the result of
oxidatiort of ammonia and of  organic  nitrogen.   Nitrates  as  N
should  rjot  exceed  20  mg/1  in  water  supplies.12   They  are
essential nutrients for algae and other aquatic life.  For  these
reasons,  effluent  limitations  for  1983  were  established for
nitrites^nitrates as N.  Nitrites typically range from  0.001  to
2.0  mg/1  in  the  raw  wastes  and from 0.02 to 1.0 mg/1 in the
treated wastes; nitrates range from O.I to 4.1 mg/1  in  the  raw
and from 0.15 to 17.5 mg/1 in the treated wastes.

Nitrates  are considered to be among the poisonous ingredients of
mineralized waters, with potassium nitrate being  more  poisonous
than  sodium  nitrate.   Excess  nitrates cause irritation of the
mucous linings of the gastrointestinal tract and the bladder; the
symptoms are diarrhea and diuresis, and  drinking  one  liter  of
water containing 500 mg/1 of nitrate can cause such symptoms.

Infant  methemoglobinemia,  a  disease  characterized  by certain
specific blood changes  and  cyanosis,  may  be  caused  by  high
nitrate  concentrations  in  the water, used for preparing feeding
formulae.   While  it  is  still  impossible  to  s ate   precise
concentration  limits,  it has been widely recommended that water
containing more than 10 mg/1 of nitrate nitrogen   ,NO3-N)  should
not   be;   used  for  infants.   Nitrates  are  a so  harmful  in
fermentation processes and can cause disagreeable tastes in beer.

Nitrates and nitrites  are  important  measurements,  along  with
Kjeldahl  nitrogen,  in  that they allow for the calculation of  a
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nitrogen balance on the treatment system.   In  fact,  the  field
sampling data verified that when there was a substantial nitrogen
reduction  by  the  treatment  system, it was accompanied by good
BOD5, TSS, and grease reduction.


                           Phosphorus

Phosphorus, commonly reported as P, is  a  nutrient  for  aquatic
plant  life  and  can therefore cause an increased eutrophication
rate in water courses.  The threshold concentration of phosphorus
in receiving bodies that can lead to eutrophication is about 0.01
mg/1.  The primary  sources  of  phosphorus  in  raw  waste  from
poultry  processing plants are bone meal from cutting, detergents
used in cleanup,  food  additives,  and  boiler-water  additives.
Effluent limitations were established for phosphorus for the 1983
limits because of its effect on eutrophication rates.


During the past 30 years, a formidable case has developed for the
belief  that  increasing standing crops of aquatic plant growths,
which often interfere with water uses and are nuisances  to  man,
frequently are caused by increasing supplies of phosphorus.  Such
phenomena   are   associated  with  a  condition  of  accelerated
eutrophication or aging of waters.  It  is  generally  recognized
that  phosphorus  is  not  the  sole cause of eutrophication, but
there is evidence to substantiate that it is frequently  the  key
element  in all of the elements required by freshwater plants and
is generally present  in  the  least  amount  relative  to  need.
Therefore, an increase in phosphorus allows use of other, already
present,  nutrients  for  plant  growths.   Phosphorus is usually
described, for this reasons, as a "limiting factor."

When a plant population is stimulated in production and attains a
nuisance status, a large number  of  associated  liabilities  are
immediately  apparent.   Dense  populations  of  pond  weeds make
swimming dangerous.   Boating  and  water  skiing  and  sometimes
fishing  may be eliminated because of the mass of vegetation that
serves as  a  physical  impediment  to  such  activities.   Plant
populations  have  been  associated with stunted fish populations
and with poor  fishing.   Plant  nuisances  emit  vile  stenches,
impart  tastes and odors to water supplies, reduce the efficiency
of industrial and municipal  water  treatment,  impair  aesthetic
beauty,   reduce  or  restrict  resort  trade,  lower  waterfront
property values, cause skin rashes to man during  water  contact,
and serve as a desired substrate and breeding ground for flies.

Phosphorus  in  the  elemental  form  is  particularly toxic, and
subject to bioaccumulation in  much  the  same  way  as  mercury.
Colloidal  elemental  phosphorus will poison marine  fish  (causing
skin tissue breakdown and discoloration).   Also,  phosphorus  is
capable  of  being concentrated and will accumulate  in organs and
soft tissues.  Experiments  have  shown  that  marine  fish  will
concentrate phosphorus from water containing as little as  1 ug/1.
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                            Chloride

Chlorides  in  concentrations  of  the order of 5,000 mg/1 can be
harmful  to  people  and  other  animal  life,.     High   chloride
concentrations   in   waters   can  be  troublesome  for  certain
industrial uses  and  for  reuse  or  recycling  of  water.   The
concentrations  in raw waste are extremely variable from plant to
plant.  Chloride loadings are unaffected by biological  treatment
systems  used by the industry today, and once in the waste waters
they  are  very  costly   to   remove.    While   high   chloride
concentrations  in  biological  treatment  systems  and receiving
waters can  upset  the  metabolic  rate  of  organisms,  effluent
concentrations  are  probably  too  low to have a serious impact.
Consequently chloride effluent limitations were  not  established
in this report.


                         Fecal Coliform

The  coliform  bacterial  contamination   (total and fecal) of raw
waste is substantially reduced  in,  the  larger  waste  treatment
systems  used in the industry, such as anaerobic lagoons followed
by several aerobic lagoons.  Chlorination  will  reduce  coliform
counts  to  less  than 400 per 100 ml for total, and to less than
100 per 100 ml for fecal.  Typically,  States  require  that  the
total  coliform  count  not  exceed  50 to 200 MPN  {most probable
number) per 100 ml for waste  waters  discharged  into  receiving
waters.  Hence, most final effluents require chlorination to meet
State  limitations.   When waters contain greater than 200 counts
of fecal coliform per 100  ml,  it  is  assumed  that  pathogenic
enterobacteriacea,  which  can  cause  intestinal infections, are
present.  Consequently, effluent limitations were established for
fecal coliform.
Fecal  coliforms  are  used  as  ah  indicator  since  they  have
originated  from  the  intestinal  tract  of warmblooded animals.
Their presence in  water  indicates  the  potential  presence  of
pathogenic bacteria and viruses.

The  presence of coliforms, more specifically fecal coliforms, in
water is indicative of fecal pollution.  In general, the presence
of  tecal  coliform  organisms  indicates  recent  and   possibly
dangerous  fecal  contamination.   When  the fecal coliform count
exceeds 2,000 per  100  ml  there  is  a  high  correlation  with
increased numbers of both pathogenic viruses and ba< teria.

Many  microorganisms,  pathogenic  to  humans and  .nimals, may be
carried in surface water, particularly that deriv d from effluent
sources which find their way into surface  water  from  municipal
and  industrial  wastes.   The  diseases associated with bacteria
include   bacillary    and    amoebic    dysentery.    Salmonella
gastroenteritis,  typhoid  and paratyphoid fevers, leptospirosis.
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chlorea,, vibriosis and infectious hepatitis.  Recent studies have
emphasized the value of fecal coliform density in  assessing  the
occurrence  of Salmonella, a common bacterial pathogen in surface
water.  Field studies involving irrigation  water,  field  crops,
and soils indicate that when the fecal coliform density in stream
waters  exceeded  1,000  per 100 ml, the occurrence of Salmonella
was 53-5 percent.


                   pHff Acidity* and Alkalinity

pH is of relatively minor importance,  although  waters  with  pH
outside  the  6.0  to  9.0  range can affect the survival of most
organi^mSj, particularly invertebrates.   The  usual  pH  for  raw
waste falls between 6,0 to 9.0.  This pH range is close enough to
neutrality  that  it  does  not  significantly  affect  treatment
effectiveness or effluent quality.  However, some adjustment  may
be required, particularly if pH adjustment has been used to lower
the  pH  for  protein precipitation, or if the pH has been raised
for ammonia stripping.  The pH of the waste water then should  be
returned  to  its  normal  range before discharge.  The effect of
chemical  additions  for  pH  adjustment  should  be  taken  into
consideration^ as new pollutants could result.


Acidity and alkalinity are reciprocal terms.  Acidity is produced
by  substances  that  yield  hydrogen  icns  upon  hydrolysis and
alkalinity is produced by substances that  yield  hydroxyl  ions.
The  terirs  "total acidity" and "total alkalinity" are often used
to express the buffering capacity  of  a  solution.   Acidity  in
natural waters is caused by carbon dioxide, mineral acids, weakly
dissociated  acids, and the salts of strong acids and weak bases.
Alkalinity is caused by strong bases  and  the  salts  of  strong
alkalies and weak acids,

The  term  pK is a logarithmic expression of the concentration of
hydrogen ions.  At a pH of  7,  the  hydrogen  and  hydroxyl  ion
concentrations  are  essentially  equal and the water is neutral.
Lower pH values indicate acidity  while  higher  values  indicate
alkalinity,,    The   relationship   between  pH  and  acidity  or
alkalinity is not necessarily linear or direct.

Waters  with  a  pH  below  6.0  are  corrosive   to   waterworks
structures,  distribution  lines, and household plumbing fixtures
and can thi;s add such constituents to  drinking  water  as  iron,
copper,  zinc,  cadmium and lead.  The hydrogen ion concentration
can affect the taste of the water.  At a  low  pH,  water  tastes
"sour," The bactericidal effect of chlorine is weakened as the pH
increases,  and  it  is  advantageous  to keep the pH close to 7.
This is very significant for providing safe drinking water.

Extremes of pH or rapid pH changes can exert stress conditions or
kill aquatic life outright.  Dead rish, associated algal  blooms,
and  foul  stenches  are  aesthetic  liabilities of any waterway.
Even moderate changes from "acceptable" criteria limits of pH are
                                80

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deleterious to some species.  The relative  toxicity  to  aquatic
life  of  many materials is increased by changes in the water pH.
Metalocyanide complexes can increase a thousand-fold in  toxicity
with  a  drop of 1.5 pH units.  The availability of many nutrient
substances varies with the alkalinity and  acidity.   Ammonia  is
more lethal with a higher pH.

The  lacrimal  fluid  of  the human eye has a pH of approximately
7.0, and a deviation of 0.1 pH unit from the norm may  result  in
eye  irritation  for  the  swimmer-   Appreciable irritation will
cause severe pain.
Because of  the  long  detention  time  at  ambient  temperatures
associated with typically large biological treatment systems used
for  treating  poultry processing waste water, the temperature of
the treatment effluent from most poultry processing  plants  will
be virtually the same as the temperature of the receiving body of
water.   Therefore,  temperature  effluent  limitations  were not
established.  Temperatures of the raw waste waters are  typically
about 18°C  (65°F).


Temperature  is  one  of the most important and influential water
quality characteristics.  Temperature  determines  those  species
that  may  be  present;  it  activates  the  hatching  of  young,
regulates their activity,  and  stimulates  or  suppresses  their
growth  and development; it attracts, and may kill wher the water
becomes too hot or becomes chilled too  suddenly.   Colder  water
generally   suppresses   development.    Warmer  water  generally
accelerates activity and may be a primary cause of aquatic  plant
nuisances when other environmental factors are suitable.

Temperature  is a prime regulator of natural processes within the
water  environment.   It  governs  physiological   functions   in
organisms  and, acting directly or indirectly in combination with
other water quality constituents, it affects  aquatic  life  with
each  change.   These  effects  include  chemical reaction rates,
enzymatic functions, molecular movements, and molecular exchanges
between membranes within and between  the  physiological  systems
and the organs of an animal.

Chemical  reaction  rates  vary  with  temperature  and generally
increase as the temperature  is  increased.   The  solubility  of
gases  in  water  varies  with  temperature.  Dissolved oxygen is
decreased by the decay  or  decomposition  of  dissolved  organic
substances and the decay rate increases as the temperature of the
water  increases,  reaching  a maximum at about 3' C  (86QF).  The
temperature of stream water, even during  summer,  is  below  the
optimum  for pollution-associated bacteria.  Increasing the water
temperature increases the bacterial multiplication rate when  the
environment is favorable and the food supply is abundant.

                                81

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Reproduction  cycles  may  be  changed significantly by increased
temperature because this function takes  place  under  restricted
temperature  ranges-   Spawning  may  not  occur  at  all because
temperatures are too high.  Thus, a fish population may exist  in
a  heated  area  only by continued immigration.  Disregarding the
decreased reproductive potential,  water  temperatures  need  not
reach  lethal  levels  to  decimate a species.  Temperatures that
favor competitors, predators, parasites, and disease can  destroy
a species at levels far below those that are lethal.

Fish  food  organisms  are  altered  severely  when  temperatures
approach or  exceed  90°F.   Predominant  algal  species  change,
primary  production is decreased, and bcttom-associated organisms
may  be  depleted  or  aItered   drasti cally   in   numbers   and
distribution.   Increased  water  temperatures  may cause aquatic
plant nuisances when other environmental factors are favorable.

Synergistic actions of pollutants are more severe at higher water
temperatures.  Given amounts of domestic sewage, refinery wastes,
oils,  tars,  insecticides,  detergents,  and  fertilizers   more
rapidly  deplete  oxygen in water at higher temperatures, and the
respective toxicities are likewise increased.

When water temperatures increase, the predominant  algal  species
may  change  from  diatoms  to  green  algae, and finally at high
temperatures to blue-green algae, because of species  temperature
preferentials.  Blue-green algae can cause serious odor problems.
The  number  and  distribution  of benthic organisms decreases as
water temperatures increase above 90°F, which  is  close  to  the
tolerance  limit for the population.  This could seriously affect
certain fish that depend on benthic organisms as a food source.

The cost of fish being attracted to heated Water in winter months
may be considerable, due to fish mortalities that may result when
the fish return to the cooler water.

Rising  temperatures  stimulate  the  decomposition  of   sludge,
formation  o£  sludge gas, multiplication of saprophytic bacteria
and fungi (particularly in the presence of organic  wastes),  and
the   consumption  of  oxygen  by  putrefactive  processes,  thus
affecting the esthetic value of a water course.

In general, marine water temperatures do not change as rapidly or
range as widely as those of  freshwater.   Marine  and  estuarine
fishes,  therefore*  are  less tolerant of temperature variation.
Although this limited tolerance is greater in estuarine  than  in
open-water marine species? temperature changes are more important
to  those  fishes  in  estuaries  and  bays than to those in open
marine areas, because of the nursery and replenishment  functions
of  the  estuary  that  can  be  adversely  affected  by  extreme
temperature changes.
                                 82

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                           SECTION VII

                CONTROL AND TREATMENT TECHNOLOGY


                             SUMMARY

The waste load discharged from the poultry processing industry to
receiving streams can be reduced to desired levels, including  no
discharge  of  pollutants, by conscientious water management, in-
plant waste controls, process revisions, and  by  the  use  of  a
primary, biological and advanced was^te water treatment.  Figure 9
is  a  schematic  of  a suggested waste reduction program for the
poultry industry to achieve a high quality effluent.

This section describes many of the  techniques  and  technologies
that  are  available  or  that are being developed to achieve the
various levels of waste reduction.  In-plant  control  techniques
and  waste  water  management  suggestions  are  described first.
Waste treatment technology normally used as a  primary  treatment
is  then  described.   In  the  case  of  the  poultry processing
industry, this "primary" treatment is considered as part  of  the
in-plant  system,  although  many  of  these  systems  have  been
installed to reduce  pollution  levels  as  well  as  to  recover
byproducts.   The  effluent  from primary treatment is considered
the "raw waste."  Secondary treatment systems  are  used  in  the
treatment of the raw waste.

Each  treatment process is described, and the specific advantages
and disadvantages of each system, and the  effectiveness  of  the
specific  waste  water  contaminants  foxind in poultry processing
waste are discussed.  The advanced  treatment  systems  that  are
applicable to the waste from typical poultry plants are described
in  the  last  part  of  this  section.   Some  of these advanced
treatment systems have not been used on  full-scale  for  poultry
processing   plant  waste;  therefore,  the  development  status,
reliability, and potential  problems  are  discussed  in  greater
detail than for the primary and biological treatment systems that
are in widespread use.
                   IN-PLANT CONTROL TECHNIQUES

The  waste  load from a poultry processing plant is composed of a
waste water stream containing the; various pollutants described in
Section VI.  The cost and effectiveness of treatment of the waste
stream will vary with the quantity of water and the  waste  load.
In-plant  control techniques will reduce both water use and waste
load.  The latter will be reduced by minimizing the entry of  raw
materials  into the waste water stream, and the former by cleanup
frequency and procedures and by controlling  the  water  use  for
high water-use operations and by reusing waste w .ters.

The  in-plant  changes  that  may be made in each plant to reduce
water  use  and  waste  load  will  depend  upon  the  particular

-------
                  Waste Reduction
                   Techniques
CO
                  Waste Reduction
                     Effect
                     Point  of
                    Application
Waste
Water
Mgmt. &
In-Plant
Controls


Water-
Flow &
Waste
Load
Reduction


Plant
Operations
— *

Screening,
Skimming,
Settling -
3y- Product
Recovery
and Primary
Treatment


By- Produce
Recovery,
Grease,
& Coarse
Solids
Removal


In-Plant
—+


**

Dissolved
Air
Flotation


By-Product
Recovery,
Grease,
Sus. Solid:
Removal


In-Plant




Secondary


BOD, Sus.
Solids,
Grease
Removal
to 97.7%
BOD 5


End-of
Process
-*
Partial
Tertiary
Treatment
]
j Irrlg
j Evapoi
i



.
it ion
-ation

Removal of
Fine Sus.
Solids, Salt,
Phosphorus ,
Ammonia (as
necessary)
to 97.7%
SOD5


Post
Secondary
Treatment





No
Discharge


Post
Secondary
Treatment
                              "Figure '9.   Suggested -Poultry..Processing Industry Waste Reduction  Program

-------
circumstances at that plant.  A good understanding of the sources
of  water use and waste load, however,  would be very useful prior
to implementation of improved jvater management practices.   Waste
water  and  waste load sources are discussed in detail in Section
V.  Unfortunately, efforts made by many poultry processing plants
to improve the quality of the final treated  effluent  have  been
directed at improvements in the treatment system only, and not in
in-plant control techniques.

The following is a list of in-plant control techniques which have
been  used  by poultry processing plants or have been shown to be
technically feasible in other applications  for  improving  water
management practices:

     o  Appoint a person with specific responsibility for waste and
        water management.  This person should have reasonable powers
        to enforce improvements, both in the plant and outside.

     o  Determine or estimate water use and waste load strength
        from various sources.  Install flowmeters and monitor flows
        in all major water use areas.

     o  Control and minimize flow of freshwater at major outlets
        by installing properly sized spray nozzles and by regulating
        pressure on supply lines.  On hand washers, this may require
        installation of press-to-operate valves.

     o  Stun birds in the killing operation to reduce carcass
        movement during bleeding,

     o  Confine bleeding and provide for sufficient bleed time.
        Recover all collectable blood and ship to rendering in tanks
        rather than by dumping on top of offal.

     o  Use minimum OSDA-approved quantities of water in the scalder
        and chillers.

     o  Shut off all unnecessary water flow during work breaks.

     o  Consider the reuse of chiller water for makeup water for the
        scalder.  This may  require preheating the chiller effluent
        with the scalder overflow water by using a simple heat
        exchanger.

     o  consider dry offal  handling as an alternative to fluming.
        A number of plants  had demonstrated the feasibility of dry
        offal handling in modern high-production poultry slaughtering
        operations.

     o  Control the water use in gizzard machine.

     o  Provide for regularly scheduled observanca of screening
        and handling systems, for offal and feathers.  A back-up
        screen may be required to prevent these materials from
        entering municipal  or private waste treatment systems where
                                 85

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        they may cause problems.

     o  Treat ofifal truck drainage before sewering.  One method is
        to steam sparge the collected drainage and then screen.

     o  Use dry cleanup prior to washdown on all floors and tables
        to reduce the waste load-  This is particularly important
        in the bleeding and cutting areas and all other areas hThere
        there tends to be spillage of materials*

     o  Use high-pressure, low-volume spray nozzles or
        steam-augmented systems for plant
     o  Minimize the amount of chemicals and detergents to prevent
        emulsification or solubilizing of solids in the waste watery,
        For example,, determine the minimum amount of chGRlcals that
        will be effective in cleaning the scald tank.

     o  Control inventories of raw materials used in further
        processing so that none of these materials are ever wjs-tacl
        to the sewer.  Spent raw materials ?houl-3 be routed to
        rendering.

     o  Treat separately all overflow of cooking broth for grease
        and solids recovery.

     o  Make all employees aware of good water management practices
        and encourage them to apply these practices.


                 Byproduct Recovery (Screening)

Byproduct  recovery  of offal and feathers from flow-away systems
in the slaughtering and dressing of poultry  is  accomplished  by
various screening techniques.  These operations may or may not be
followed by in-plant primary treatment such as gravity separation
basins  or  air  flotation  systems, or even biological screening
systems,

Screens vary widely both in mechanical action and in  mesh  size,
which  ranges from 0. 5-inch openings in stationary screens to 200
mesh in high-speed circular vibratory polishing screens.  In some
cases the efficiency of screening in the flow-away systems may be
sufficient  to  circumvent  biological  screening;   in   others,
biological or polishing screening may be warranted.  Floor drains
not   connected   to  the  flow-away  systems  are  usually  then
discharged  to  this  polishing  screen.   With   no   biological
screening,  the floor drains in the offal room and those adjacent
to the flow-away screens and offal  conveyors  should  be  pumped
back  to  the  flow-away screen influent.  These floor drains a*e
frequently the source of serious problems when diff icult.ies arise
in the flow-away screen systems or conveyors.


                                86

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Rotary Screens

Rotary and vibratory  screens  are  the  most  popular  types  of
screening  systems  used  by  the  poultry industry for offal and
feather recovery from the flow-away systems.  One type of  barrel
or  rotary screen, driven by external rollers, receives the waste
water at one open end and discharges the solids at the other open
end.  The screen is inclined toward the exit  end  to  facilitate
movement of solids.  The liquid passes outward through the screen
(usually  stainless  steel screen cloth or perforated sheet) £o a
receiver and then to the sewer.  To prevent clogging, the  screen
is  usually  sprayed  continuously  by  a  line of external spray
nozzles.l3                                                    •

Another rotary screen occasionally used for byproduct recovery or
for in-plant primary in the poultry industry^  is  driven  by  an
external  pinion  gear*   The  raw  waste  water  is fed into the
interior of the screen, below the longitudinal axisp  and  solids
are  removed in a trough-and-screw conveyor mounted lengthwis^ at
the axis (center line) of the barrel.  The liquid  exits  outward
through  the  screen into a tank under the screen.  The screeri is
partially submerged in the liquid in the  tank.   The  screen  is
usually  UO  by  UO  mesh,  with  G0<4  mm   (1/6**  inch) openings.
Perforated lift paddles mounted lengthwise on the inside  surface
of  the  screen  assist  in  lifting  the  solids to the conveyor
trough.  This type is also generally sprayed externally to reduce
blinding.  Grease clogging can be reduced  by  coating  the  wire
cloth   with   tefIon.   Solids  remova1  up  to  82  percent  is
reported*t3


Applications

A broad  range  of  applications  exists  for  screens  for  both
byproduct   recovery   and   for  in-plant  primary  waste  water
treatment.   These include both the plant waste  water  and  waste
water discharged from individual sources, especially streams with
high solids contents sxich as offal truck drainage.  In one modern
poultry   treatment  facility,  a  rotary  screen  equipped  with
microscreening was successfully used for advanced  treatment—the
final BOD5 from this plant was consistently under 15 mg/1.


Vibrating Screens

Vibratory   screens  are  commonly  used  to  recover  offal  and
feathers.  The effectiveness of a vibrating screen depends  on  a
rapid  motion.   Vibrating  screens  operate between 99 and 1,800
rpm; the motion can be either circular or straight .ine,  varying
from  0.08 to 1.27 cm (1/32 to 1/2 inch) total tra el.  The speed
and motion are  selected  by  the  screen  manufacturer  for  the
particular application.

Of prime importance in the selection of a proper vibrating screen
is the application of the proper cloth.  The liquid capacities of
                                   87

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vibrating  screens  are  based on the percent of open area of the
cloth.  The cloth is selected  with  the  proper  combination  of
strength  of  wire and percent of open area.  If the waste solids
to be handled are heavy and abrasive, wire of  greater  thickness
should  be used to assure long life,,  However, if the material is
light or sticky  in  nature,  the  durability  of  the  screening
surface  may be the least consideration.  In such a case, a light
wire may be desired to provide an increased percent of open area.


Applications

For  offal  recovery,  vibratory  screens  usually  have  20-mesh
screening;  for  feather  removal as well as for in-plant primary
treatment of combined waste water, a 36- by UO-mesh screen  cloth
is  used.   On  most  applications a double-crimped, square-weave
cloth is used because of its inherent strength and resistance  to
wire  shifting.   Vibratory screens with straight-line action are
largely used for byproduct recovery, while  those  with  circular
motion are frequently used for in-plant primary treatment.


Static Screens

The  primary  function  of a static screen is to remove "free" or
transporting fluids.  This can be accomplished in  several  ways,
and in most older conceptse only gravity drainage is involved.  A
concavely  curved  screen  design  using  high-velocity  pressure
feeding was developed and patented  in  the  1950's  for  mineral
classification  and has been adapted to other uses in the process
industries.,  This design employs bar interference to  the  slurry
which  knives  off  thin  layers  of  the  flow  over  the curved
surface.**

Beginning in 1969, United States and foreign patents were allowed
on a three-slope static screen made of  specially  coined  curved
wires.    This   concept  used  the  Coanda  or  wall  attachment
phenomenon to withdraw the fluid from the underlayer of a  slurry
which is stratified by controlled velocity over the screen.  This
method  of  operation  has  been  found to be highly effective in
handling slurries containing fatty or  sticky  fibrous  suspended
matter.

The  specific arrangement and design of transverse wires provides
a relatively nonclogging surface  for  dewatering  or  screening.
The  screens  are precision-made, usually of 316 stainless steel,
and  are  extremely  rugged.   Harder,  wear-resisting  stainless
alloys  may also be used for special purposes.  Openings of 0.025
to 0,15 cm  (0,010 to 0-060 inch) meet normal screening needs.

Application

In some plants "follow-up" stationary screens, consisting of two,
three9 and four units placed vertically  in  the  effluent  sewer
before  discharge  to  the  municipal   sewer,  have  successfully
                                    88

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prevented escape of feathers and solids from the  drains  in  the
flow*-away  screen  room  and other drains on the premises.  These
stationary  "channel"  screens  are  framed   and   are   usually
constructed  of  mesh  or perforated stainless steel with 1/4- to
1/2-inch openings.  The series arrangement permits removal  of  a
single  screen  for cleaning and improves efficiency.  -The three-
slope static screen is being used in  a  few  poultry  processing
plants as primary treatment.


                   IN-PLANT^PRIMARY TREATMENT

Ihr plant  primary treatment in the poultry processing industry is
the treatment of waste water after the customary screening out of
byproducts from flow- away  systems  and  before  discharge  to  a
municipal sewer or private treatment system.


                        Flow Equalization

Equalization  facilities  consist  of  a holding tank and pumping
equipment designed to reduce the fluctuations of waste water flow
jthroutfh materials recovery systems.   They  can  be  economically
advantageous,  whether the industry is treating its own wastes or
discharging into a  city  sewer  after  some  pretreatment.   The
equalising  tank  should  have sufficient capacity to provide for
uniform flow to treatment facilities throughout  a  24-hour  day.
The  tank  is characterized by a varying flow into the tank and a
constant flow out.

The major advantages of equalization are that  treatment  systems
can be smaller since they can be designed for the 24-hour average
rather  than  the  peak  flows,  and many waste treatment systems
operate  much  better  when  not  subjected  to  shock  loads  or
variations  in  feed rate.  Flow equalization is vital for proper
operation of air flotation systems'* particularly  when  chemicals
have been added.
                             Screens

Since  so  much of the pollutant matter for some waste sources of
poultry processing is originally solid  (meat and fat  particles) ,
interception of the waste material by various types of screens is
a  natural  f^rst step for primary treatment.  To assure the best
performance on a plant waste wate*r stream, flow equalization  may
be headed preceding screening equipment.

Unfortunately,  when  the  pollutant  materials  er.ter the sewage
stream, they are subjected to turbulence, pumping, and mechanical
screening, and they break down and release solubl . BOD5 into  the
stream,  along  with  colloidal,  suspended,  an   grease solids.
Wa^te treatment — that is, the removal of soluble , colloidal,  and
suspended  organic  matter — is  expensive.   It  usually  is  far
simpler and less expensive to keep the solids out of the sewer.
                                  89

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Static, vibrating, and rotary screens are the primary  type  used
for  this step in the in-plant primary treatment.  These types of
screening systems were previously discussed in this section under
byproduct recovery.  The main difference  between  the  screening
systems  used  for  byproduct recovery and those used for primary
treatment, is that  the  openings  in  the  screening  cloth  for
primary  treatment  are  normally  smaller—36  to  200  mesh for
primary  versus  20  mesh  to  1.25  cm  openings  for  byproduct
recovery,   whenever  possible, pilot-scale studies are warranted
before selecting a screen, unless  specific  operating  data  are
available  for  the  specific  use  intended,  in the same solids
concentration range, and under the same operating conditions.


                          Catch Basins

The catch basin for the separation  of  grease  and  solids  from
poultry processing waste waters are being installed primarily for
waste   control   rather   tjian  to  recover  marketable  grease.
Unfortunately many catch basins in use  today  are  not  equipped
with  automatic  bottom  sludge removal equipment.  The solids in
these basins could often be completely drained to  the  sewer  or
are  "sludged  out"  periodically at frequencies such that septic
conditions would not cause the sludge to rise.  Rising sludge was
undesirable because it couloj affect  the  color  and  reduce  the
market value of the grease. < Many wet wells or sumps that receive
the  screened flow-away waters are considered catch basins by the
industry.  However the turbulence created as the screened  waters
fall  by  gravity  into  these  pits  does  not  permit efficient
separation of solids or grease.  Furthermore,  these  basins  are
not  equipped  with  automatic  skimming devices and hence grease
must be removed manually, wjiich is normally done once a day.

In the past twenty years, with waste treatment gradually becoming
an added economic incentive, catch basin design has been improved
in the solids removal area as well.   In  fact,  the  low  market
value  of  inedible  grease  and tallow has reduced concern about
quality of the skimmings, and now the concern is shifting  toward
overall  effluent  quality  improvement.  Gravity grease recovery
systems will remove 20 to 30  percent  of  the  BOD5.,  40  to  50
percent  of  the  suspended  solids,  and 50 to 60 percent of the
grease (hexane solubles).1?

The majority of the newer gravity grease recovery  basins   (catch
basins)  are  rectangular.   Flow  rate  is  the  most  important
criterion for design; 30 to 40 minutes detention time at one-hour
peak flow is a common design sizing  factor.13   The  use  of  an
equalizing  tank ahead of the catch basin obviously minimizes the
size requirement for the basin.  A shallow basin-up to 1.8  m   (6
feet)—is preferred.

A "skimmer" skims the grease and scum off the top into collecting
troughs.   A  scraper  moves  the  sludge  at  the  bottom  into a
submerged hopper from which it can be pumped or carries it up and
                                   90

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deposits it into a hopper.  Both  skimmings  and  sludge  can  be
recycled as a raw material for rendering.

Two  identical catch basins, with a common wall, are desirable so
operation can continue if pne is down for maintenance or  repair.
Both concrete and steel tanks are used.

Concrete  tanks  have  the  inherent  advantages of lower overall
maintenance and more  permanence  of  structure.   However,  some
plants  prefer  to  be  able to modify their operation for future
expansion or alterations, or even  relocation.   All-steel  tanks
have  the  advantage  of  being  semiportable, more easily field-
erected, and more easily modified than concrete tanks.  The  all-
steel  tanks, however, require additional maintenance as a result
of wear from abrasion and corrosion.

A tank using all-steel walls and a concrete  bottom  is  probably
the  best  compromise  between  the  all-steel  tank and the all-
concrete tank.   The  advantages  are  the  same  as  for  steel;
however,  the  all-steel  tank  requires a footing underneath and
supporting members, whereas the concrete bottom forms  the  floor
and supporting footings for the steel-wall tank.


                     Dissolved Air Flotation

This  system is, by definition, a primary treatment system; thus,
the effluent from a dissolved air flotation system is  considered
raw  waste.   This  system  is normally used to remove grease and
fine suspended solids.  It is a relatively recent  technology  in
the   poultry  processing  industry;  therefore,  it  is  not  in
widespread  use,  although  increasing  numbers  of  plants   are
installing these systems.

Dissolved  air flotation appears to be the single, most effective
device currently in commerpial use for a plant to use  to  reduce
the  pollutant  waste  loa£ in its raw waste water stream, and is
particularly effective when flow equalization tanks  precede  the
flotation  unit.   It  is  expected that the use of dissolved air
flotation will become more common in the industry, especially  as
a step in achieving the 1983 limitations.


Technical Description

Air  flotation  systems are used to remove any suspended material
from waste water with a specific gravity close to that pf  water.
The  dissolved  air system generates a supersaturated solution of
waste water and air by pressurizing waste water  and  introducing
compressed  air,  then  mixing the two in a detention tank.  This
"supersaturated" waste water flows  to  a  large  flotation  tank
where the pressure is released, thereby generating numerous small
air  bubbles  which effect the flotation of the suspended organic
material by one of three mechanisms:   1)  adhesion  of  the  air
bubbles  to  the  particles  of  matter;  2)  trapping of the air
                                  91

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bubbles in the floe  structures  cf  suspended  material  as  the
bubbles  rise;  and  3) adsorption of the air bubbles as the floe
structure is formed from the suspended organic matter,15  In most
cases, bottom sludge removal facilities are also provide^.

There  are  three  process  alternatives  that  differ   by   the
proportion of the waste water stream that is pressurized and into
which  the  compressed air is mixed.  In the total pressurization
process. Figure 10, the entire waste water stream  is  raised  to
full pressure for compressed air injection.

In  partial  pressurization.  Figure 11, only a part of the waste
water stream is raised to the pressure of the compressed air  for
subsequent mixing.  Alternative A of Figure 11 shows a sidestream
of  influent  entering  th§  detention  tank,  thus  reducing the
pumping required in the  system  shown  in  Figure  10.   In  the
recycle  pressurization  process,  alternative  B  of  Figure 11,
treated  effluent  from  the  flotation  tank  is  recycled   and
pressurized  for  mixing with the compressed air and then, at the
point of pressure release,  is  mixed  with  the  influent  waste
water.  Operating costs may vary slightly, but performance should
be   essentially   equal   among   the   alternatives.   Improved
performance  of  the  air  flotation  system   is   achieved   by
coagulation  of the suspended matter prior to treatment.  This is
done by pH adjustment or tf|e addition of coagulant chemicals,  or
both.  Aluminum sulfate, iron sulfate, lime, and polyelectrolytes
are used as coagulants at varying concentrations up to 300 to 400
mg/1  in  the raw waste.  These chemicals are essentially totally
removed in the dissolved air unit, thereby adding  littl^  or  no
load  to  the  downstream  waste treatment systems.  However, the
resulting float and  sludge  may  become  a  less  desirable  raw
material  for recycling through the rendering process as a result
of chemical coagulation addition.  Chemical precipitation is also
discussed later, particularly in regard  to  phosphorus  removal,
under  advanced treatment; phosphorus can also be removed at this
primary (in-plant) treatment  stage.   A  slow  paddle  mix  will
improve   coagulation.    It   has   been   suggested   that  the
proteinaceous matter in poultry processing plant waste  could  be
removed  by reducing the pt^ of the waste water to the isoelectric
point of  about  3.5.1S   The  proteinaceous  material  would  be
coagulated  at  that  point; and readily removed as float from the
top  of  the  dissolved  air  unit.   This  is  not  being   done
commercially  in the poultry industry in the United States at the
present time.

Similarly,  the  Alwatec  process  has  been  developed  using  a
lignosulfonic  acid  precipitation and dissolved air flotation to
recover a high protein product that  is  valuable  as  a  feed.1*
Nearly  instantaneous  protein  precipitation and hence, nitrogen
removal, is achieved when a high protein-containing  effluent  is
acidified  to  a  pH between 3 and U with a high molecular weight
lignosulfonic acid.  BOD5 reduction is reported to range from  60
to  95  percent.  The effluent must be neutralized before further
treatment  by  the  addition  of  milk  of  lime  or  some  other
inexpensive  alkali.   This  process  is  being evaluate^ on meat
                                  92

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Feed
         Compressed
            Air
                Toto I   Pressurization
                       Process
                                                                  Treated
                                                                  Effluent
                                                              Float
Sludge
                 Figure 10.  Dissolved Air Flotation

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                              Compressed
                                  Air
                            Recycle  Pressunzcmon
                                   Process
                                                     (Alternative 8)
                                ,	(Retention W	
                                r      \   Tank
                                                                    Treated
Feed from ^
Primary 	 i — /^ >
Treatment ! i
Flotation
Tank
	 1 	 ^

V
iri^
    1	jj Retention ]	1
            Tank
                                  Sludge
Compressed
    Air
Partial Pressurization
      Process
   (Alternative A)
     Figure 11.   Process Alternatives  for Dissolved Air Flotation

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packing waste in one plant in the United States  at  the  present
time.l7

Orie  of  the  manufacturers  of dissolved air flotation equipment
indicated a 60 percent  suspended  solids  removal  and  80-to-90
percent  grease  removal without the addition of chemicals.   With
the addition of 300 to 400 mg/1 of  inorganic  coagulants  and  a
slow  mix  to coagulate the organic matter, the manufacturer says
that 90 percent or more of the suspended solids and more than  90
percent of the grease can be removed.ie  Total nitrogen reduction
between  35  and  70  percent  was  found  in dissolved air units
surveyed in the meat packing industry.l9

North star's staff observed the operation  of  several  dissolved
air  units  during  the  verification  sampling program and plant
visits of the poultry, rendering, and  meat  packing  industries.
One  meat packing plant that was visited controlled the feed rate
and pH of the waste water and achieved 90-to-95  percent  removal
of  solids  and grease; one poultry processing plant consistently
obtained about 80-percent BOD5 reduction with the aid of chemical
coagulants.  Other plants had relatively good operating  success,
but  some  did  not  achieve  the  results  that should have been
attainable.  It appeared that they did not fully  understand  the
process chemistry and were using poor operating procedures.


Problems and Reliability

The reliability of the dissolved air flotation process and of the
equipment seems to be well established, although it is relatively
new  technology for the poultry industry.  As indicated above, it
appears that the use of the dissolved air  system  is  not  fully
exploited  by  some  of  the  companies who have installed it for
waste  water  treatment.   The  potential  reliability   of   the
dissolved  air process can be realized by  proper installation and
operation.   The  feed  rate  and  process  conditions  must   be
maintained  at  the  proper  levels  at  all times to assure this
reliability.  This fact does not seem to be fully  understood  or
of  sufficient concern to some companies and thus full benefit is
frequently not achieved.

The sludge and float taken from the dissolved air system can both
be disposed of with the sludges obtained   from  biological  waste
treatment systems.  The addition of polyelectrolyte chemicals was
reported  to  create  some  problems  for  sludge dewatering.  The
mechanical equipment involved  in  the  dissolved  air  flotation
system  is fairly simple, requiring limited maintenance attention
for such things as pumps and mechanical drives.

                       Electrocoaqulation

The concept of electrocoagulation is not new, but  only  recently
has  such  a  system  been developed and used to pretreat the raw
effluent from the meat products industries.  Results reported  on
treating  slaughterhouse  effluents*°  show a marked reduction in
                                    95

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waste strength  when  the  effects  of  chemicals  plus  electric
current  were  added to a catch basin.  The waste strength of the
effluent from the catch basin alone was  1,213,  465,  and  1,108
mg/1  for  suspended  solids, grease, and BOD5., respectively; the
respective values for a catch basin plus chemicals plus  electric
current  were  65,  15,  and  458 mg/1.  Even a greater reduction
resulted  when  pH  adjustment  was  also  used.   The  increased
reduction,  however, adds to equipment, chemical, and power cost.
In the case cited above, the equipment costs  were  increased  by
$23,000  to  $30,000 and the chemicals and power costs were about
$109/day and $5,76/day, respectively.


Technical Discussion

Electrocoagulation  provides  relatively  rapid   flotation   and
compaction  of  the  floe and can be used alone or in conjunction
with   flocculants.    As   its   name   implies,   the   process
electrolytically  neutralizes the charge on the foreign particles
to aid in forming the floe.  The tank acts as the cathode, and  a
plurality  of  anodes  is  placed  in  the waste water.  A direct
current, with voltage less than 15 v, is passed through the waste
water.  Cations formed at  the  cathode  act  to  neutralize  the
negative  charge  on  the  foreign  particles,  allowing  them to
coagulate and form an embryo floe.  Microbubbles  of  oxygen  and
hydrogen  formed  during  the  electrolysis  become entrained and
occluded in the embryo floe, causing it to rise to  the  surface.
The  skimmings  have  a  high  solids  content   (9 to 12 percent,
compared to 3 to 5 percent by  air  flotation).   Where  the  fat
loading is high, the solids content can be as high as 50 percent-
-the fat has a lower density than water, and it is hydrophobic.

Oxidation  of  constituents that can be oxidized at the operating
voltage occurs at the anodes; e.g., if sulfide is present in  the
wastewater,  sulfur  will  be  formed.   If  chloride is present,
chlorine is formed and is effective as a  disinfectant,  reducing
bacteria counts.

There are also indications that the microbubbles themselves carry
a  positive charge, which helps to neutralize the negative charge
on the foreign particles.

The choice of electrode material is important if the  process  is
to  be efficient and trouble free.  It is important not to use an
anode that has an appreciable dissolution  rate,  and  especially
important  not.  to  use  an  anode  that puts toxic ions into the
solution.

The placement of the electrodes is also critical.  The electrodes
are placed to get the desired field gradient; a  higher  gradient
at  the inlet to the tank provides a higher incidence of particle
collisions required for coagulation.
                                   96

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                  WASTE WATER TREATMENT SYSTEMS

The biological treatment methods commonly used for the  treatment
of   poultry  processing  plant  wastes  after  in-plant  primary
treatment (solids removal) are the following biological  systems:
anaerobic  processes,  aerobic  lagoons,  and  variations  of the
activated sludge process.  Several of these systems  are  capable
of  providing  up  to  97-percent  BOD5 reductions and 95-percent
suspended solids reduction, as  observed  at  facilities  in  all
segments of the meat industry.  Combinations of these systems can
achieve reductions up to 97.7 percent in BOD5, up to 96.7 percent
in grease, and up to 97.7 percent in suspended solids for poultry
processing  plant  waste  water.   Based on preliminary operating
data, the rotating biological contactor also shows potential as a
biological treatment system.

The selection of a biological system  for  treatment  of  poultry
processing plant wastes depends upon a number of important system
characteristics.   Some  of  these  are waste water volume, waste
load   concentration,   equipment   used,   pollution   reduction
effectiveness  required,  reliability, consistency, and resulting
biological pollution problems  (e.g.,  sludge  disposal  and  odor
control).   The  principals governing the design and operation of
lagoon systems are the same for any substantially organic  waste,
i.e.,municipal   (domestic)  wastes,  meat  processing  wastes, or
vegetable processing wastes.   Each  source,  however,  possesses
somewhat   differing  characteristics  in  waste  strength  which
necessitate design adjustments, but all such  wastes  are  highly
amenable  to biological treatment.  Poultry processing wastes are
readily degraded by biological processes, thus lagoon systems and
other  biological   treatment   are   particularly   appropriate.
Geographical location of the poultry plant has a distinct bearing
on  the  design  and operation of such treatment; in turn, design
and operation can readily accommodate temperature  considerations
in  any  given  area.83   Northern  locations  may dictate longer
hydraulic or solids  detention  times  than  in  southern  areas,
whereas  southern locations may require more frequent cleanup  (by
draining lagoons) or lower organic loading rates than in northern
areas.  Expected reduction in effluent flow relative to raw waste
flow  (as may be due to evaporation or seepage  from  lagoons)  is
also  important in design.  Some plants have already incorporated
a "polishing" clarifier as part of  biological  treatment.   This
helps by both removing suspended solids and permitting recycle of
sludge for balancing organism activity.

More  detailed discussions of the characteristics and performance
of each of the above-mentioned biological treatment systems,  and
also  for  common  combinations  of  them,  are  described below.
Capital and operating costs are discussed in Section VIII.


                       Anaerobic Processes

The warm waste water temperatures  (20° to 31°C, or 68°  to  88°F)
and   high  concentrations of   carbohydrates,  fats, proteins, and


                                  97

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nutrients which characterize most poultry processing plant wastes
make these wastes suited to anaerobic  treatment.   Anaerobic  or
facultative  microorganisms,  which  function  in  the absence of
dissolved oxygen, break down the organic wastes to  intermediates
such  as  organic  acids  and  alcohols.   Methane  bacteria then
convert  the  intermediates  primarily  to  carbon  dioxide   and
methane.   Unfortunately, much of the organic nitrogen present in
the influent is converted to ammonia nitrogen.  Also,  if  sulfur
compounds are present  (such as from high-sulfate raw water—50 to
100  mg/1  sulfate),  hydrogen  sulfide  will be generated.  Acid
conditions  are  undesirable   because   methane   formation   is
suppressed  and  noxious  odors develop.  Anaerobic processes are
economical because they provide high overall removal of BODI5  and
suspended solids with no power cost (other than pumping)  and with
low  land  requirements.   Two  types  of anaerobic processes are
used: anaerobic lagoons and anaerobic contact systems.

Anaerobic Lagoons

Anaerobic lagoons are in common use  in  the  poultry  processing
industry  as  the  first  step  in  biological  treatment  or  as
pretreatment  prior  to  discharge   to   a   municipal   system.
Reductions  of  up  to 97-percent in BOD5 and up to 95-percent in
suspended solids can te achieved  with  the  lagoons;  85-percent
reduction is common.  Occasionally two anaerobic lagoons are used
in   parallel   and  sometimes  in  series.   These  lagoons  are
relatively deep (3 to 5 meters, or about  10  to  17  feet),  low
surface-area systems with typical waste loadings of 240 to 320 kg
BOD5/1000  cubic  meters  (15  to 20 lb BOD5/1000 cubic feet) and
detention times of five to ten days.

Plastic covers of nylon-reinforced  Hypalon,  polyvinyl  chloride
and  styrofoam  have been used on occasion by other industries in
place of a scum layer; in fact, some States require this,  A scum
layer may be used  to  retard  heat  loss,  to  insure  anaerobic
conditions,  and  hopefully  to retain obnoxious odors.  Properly
installed covers provide a convenient means for odor control  and
collection of the byproduct methane gas.

The  waste  water  flow inlet should be located near, but not on,
the bottom of the  lagoon.   In  some  installations,  sludge  is
recycled to insure adequate anaerobic seed for the influent.  The
outlet  from  the  lagoon  should  be  located  to  prevent short
circuiting of the flow and carry-rover of the scum layer.

For best operation, the pH should be between  7.0  and  8.5.   At
lower  pH, methane-forming bacteria will not survive and the acid
formers will take over to produce very noxious odors.  At a  high
pH  (above 8.5), acidforming bacteria will be suppressed and lower
the lagoon efficiency.
                                   98

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Advantages-Disadvantages

Advantages  of  an  anaerobic lagoon system are initial low cost,
ease of operation, and the ability to handle larqe  grease  loads
and  shock  waste loads, and yet continue to provide a consistent
quality effluent.2* Disadvantages of an anaerobic lagoon are  the
hydrogen sulfide generated from sulfate-containing waters and the
typically high ammonia concentrations in the effluent of 100 mg/1
or  more.   If  acid  conditions  develop,  severe  odor probiems
result.  Incidentally, if the gases evolved are contained, it  is
possible to use iron filings to remove sulfides.


Applications

Anaerobic lagoons used as the first stage in biological treatment
are  usually  followed  by  aerobic  lagoons.   Placing  a small,
mechanically aerated lagoon between  the  anaerobic  and  aerobic
lagoons is becoming popular.  A number of meat packing plants are
currently   installing  extended  aeration  units  following  the
anaerobic lagoons to obtain nitrification.  Anaerobic lagoons are
not permitted in some States or areas where the ground  water  is
high  or  the  soil  conditions are adverse  (e.g., too porous) or
because of odor problems.
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                         Aerated Lagoons

Aerated lagoons have been used successfully for many years  in  a
modest  number of installations treating meat packing and poultry
processing  plant  wastes.   However,  with  the  tightening   of
effluent  limitations,  and  because  aerated lagoons can provide
additional treatment and enhance beneficial  biological  activity
in  aerobic  lagoons  (otherwise) receiving an anaerobic influent,
the number of installations is increasing.

Aerated  lagoons  use  either   fixed   mechanical   turbine-type
aerators,  floating  propeller-type  aerators,  or a diffused air
system for supplying oxygen to  the  waste  water.   The  lagoons
usually  are  2.4  to 4.6 meters (8 to 145 feet) deep, and have a
detention time of two to ten days.   BOD5 reductions range from 40
to 60 percent, with little or no reduction in  suspended  solids.
Because  of  this, aerated lagoons approach conditions similar to
extended aeration without sludge recycle  (see below).


Advantages-Disadvantages

Advantages of this system are that it can rapidly  add  dissolved
oxygen  (DO) to convert anaerobic effluent to an aerobic state; it
provides  additional BODJ3 reduction; and it requires a relatively
small amount of land.  Aeration is of particular importance  both
as  a  means to assure that aerobic lagoons get a "head start" in
aerobic digestion, and as a process which stabilizes fluctuations
in performance in anaerobic systems.  Disadvantages  include  the
power  requirements  and  the  fact  that  the aerated lagoon, in
itself,  usually  does  not  reduce  BODj>  and  suspended  solids
adequately  to  be  used as the final stage in a high performance
biological system.


Applications

Aerated lagoons  are  usually  the  first  or  second  stages  of
biological  treatment,  and must be followed by aerobic  (shallow)
lagoons to reduce suspended solids and to  provide  the  required
final treatment.
                         Aerobic Lagoons

Aerobic   lagoons   (stabilization   lagoons or oxidation ponds) are
large surface area, shallow  lagoons, usually 1 to 2.3  meters   (3
to  8  feet)  deep,  loaded  at a BOD5 rate of 20 to  50 pounds per
acre.  Detention times vary  from about  one month to  six or   seven
months;   thus,  aerobic  lagoons require large areas  of land.  Use
of a series  of  these   lagoons   (with  or  without  supplemental
aeration)  virtually  assures  sustenance  of the bacteriological
activity  necessary for efficient biological treatment under  even
the harshest climatic conditions.
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Aerobic lagoons serve three main functions in waste reduction;

     o  Allow solids to settle out;

     o  Equalize and control flow;

     o  Permit stabilization of organic matter by aerobic anfi
        facultative microorganisms and also by algae.

Actually,  if  the  pond is quite deep, 1.8 to 2.4 meters  (6 to 8
feet), the waste water near the bottom may be void  of  dissolved
oxygen  and  anaerobic  organisms  may  be  present.   Therefore,
settled solids can be decomposed into inert and  soluble  organic
matter by aerobic, anaerobic, or facultative organisms, depending
upon  the  lagoon conditions.  The soluble organic matter is also
decomposed  by  microorganisms.   It  is  essential  to  maintain
aerobic  conditions in at least the upper six to twelve inches in
shallow lagoons, since  aerobic  microorganisms  cause  the  most
complete  removal  of  organic  matter.   Wind  action assists in
carrying  the  upper  layer  of  liquid  (aerated  by   air-water
interface and photosynthesis) down into the deeper portions.  The
anaerobic   decomposition   generally  occurring  in  the  bottom
converts solids to liquid organics, which  can  become  nutrients
for the aerobic organisms in the upper zone.

Algae growth is common in aerobic lagoons;  this may be a drawback
when  aerobic  lagoons  are  used for final treatment because tha
algae will appear as suspended solids and contribute BOD5.  Algae
added to receiving waters .are thus considered a pollutant.  Algae
in the effluent may be reduced by drawing off the lagoon effluent
at least  30  cm  (about  14  inches)   below  the  surface  where
concentrations  are  usually lower, periodic maintenance cleaning
of the lagoon, installation of small clarifier, or a  combination
of  these  actions.    Algae  in  the  lagoon,  however,  play  an
important  role  in  stabilization.   They  use  CO2,   sulfates,
nitrates,  phosphates, water and sunlight to synthesize their own
organic cellular matter and give off oxygen.  The oxygen may then
be used by other microorganisms for  their  metabolic  processes.
However,  when algae die they release their organic matter in th
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is no ice and snow cover on large aerobic lagoons, high winds can
develop  a  strong  wave  action  that can damage dikes.  Riprap,
segmented lagoons, and finger dikes  are  used  to  prevent  wave
damage.   Finger dikes, when arranged appropriately, also prevent
short circuiting of the waste water through the  lagoon.   Rodent
and weed control, and dike maintenance are all essential tor good
operation of the lagoons.


Advantages-Disadvantages

Advantages  of aerobic lagoons are that they reduce the suspended
solids and colloidal matter, and oxidize the  organic  matter  of
the  influent  to  the  lagoon; they also permit flow control and
waste water storage.   Disadvantages  are  reduced  effectiveness
during  winter  months  that  may require extended "no discharge"
detention periods  (90 days or more), the large land requirements,
a possibility for excessive algae for which counter measures  may
be  required,  and odor problems for a short time in spring, after
the ice melts and before the lagoon becomes aerobic again.


Appli cation s

Aerobic  lagoons  usually  are  the  last  stage  in   biological
treatment  and  frequently  follow  anaerobic  or anaerobic-plus-
aerated lagoons.  Large aerobic lagoons  allow  plants  to  store
waste  waters  for  discharge  during periods of high flow in the
receiving body of water  or  to  store  for  irrigation  purposes
during  the  summer.   These  lagoons are particularly popular in
rural areas where land is available and relatively inexpensive.


                        Activated Sludge

The conventional activated sludge process is schematically  shown
in  Figure  12.   In  this process, recycled, biologically active
sludge or floe is mixed in aerated tanks  or  basins  with  waste
water.  The microorganisms in the floe adsorb organic matter from
the  wastes  and  convert  it by oxidation-enzyme systems to such
stable products as carbon dioxide, water, and sometimes  nitrates
and  sulfates.   The  time  required for digestion depends on the
type of waste and its concentration, but the average time is  six
hours.   The  floe, which is a mixture of microorganisms  (bacter,
protozoa, and filamentous types), food, and slime  material,  can
assimilate organic matter rapidly when properly activated; hence,
the name activated sludge.

From  the  aeration  tank,  the  mixed sludge and waste water, in
which little nitrification has taken place, are discharged  to  a
sedimentation  tank.   Here  the  sludge settles out, producing a
clear effluent, low in BODjj, and a biologically active sludge.  A
portion of the settled sludge,  normally  about  20  percent,  is
recycled  to  serve  as  an inoculum and to maintain a high mixed
liquor  suspended  solids  content.   Excess  sludge  is  removed
                                  102

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o
i-o
 Raw
Waste
                                         Primary
                                     Sedimentation
                                               Secondary
                                             Sedimentation
Aeration  Tank
                                                            Activated
Effluent
                                             Waste
                                             Sludge
                                               Waste I
                                              Sludge^
                                           Figure 12.   Activated Sludge Process

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 (wasted)  from the system, to thickeners and anaerobic digestion,
to  chemical  treatment   and   dewatering   by   filtration   or
centrifugation,   or  to  land  disposal  where  it  is  used  as
fertilizer and soil conditioner to aid biological crop growth.

This conventional activated sludge process can  reduce  BOD5  and
suspended  solids  up  to 95 percent.  However, it cannot readily
handle shock loads and widely varying flows and  therefore  might
require upstream flow equalization.

Various  modifications  of the activated sludge process have been
developed, such as the tapered aeration, step  aeration,  contact
stabilization,   and   extended  aeration.   Of  these,  extended
aeration processes are most frequently being used  for  treatment
of   meat  processing,  meat  packing,  poultry  processing,  and
rendering wastes.

                        Extended Aeration

The extended aeration process  is  similar  to  the  conventional
activated  sludge  process,  except that the mixture of activated
sludge and raw materials is maintained in  the  aeration  chamber
for longer periods of time.  The usual detention time in extended
aeration  ranges from one to three days, rather than six hours as
in the  conventional  process.   During  this  prolonged  contact
between  the  sludge  and  raw waste, there is ample time for the
organic matter to be adsorbed by the  sludge  and  also  for  the
organisms  to  metabolize  the  organic  matter  which  they have
adsorbed.  This allows for a  much  greater  removal  of  organic
matter.  In addition, the organisms undergo a considerable amount
of  endogenous  respiration,  and  therefore  oxidize much of the
organic matter which has been built up into the protoplasm of the
organism.  Hence, in addition to high organic removals  from  the
waste  waters,  up  to  75  percent  of the organic matter of the
microorganisms  is   decomposed   into   stable   products,   and
consequently less sludge will have to be handled.

In  extended  aeration,  as  in the conventional activated sludge
process, it is necessary to  have  a  final  sedimentation  tank.
Some  of  the  solids resulting from extended aeration are rather
finely divided and therefore settle slowly,  requiring  a  longer
period of settling.

The  long  detention  time in the extended aeration tank makes it
possible for nitrification  to  occur.   In  nitrification  under
aerobic conditions, ammonia is converted to nitrites and nitrates
by specific groups of nitrifying bacteria.  For this to occur, it
is  necessary  to  have  sludge  detention times in excess of ten
days.21  This can be accomplished by regulating  the  amounts  of
recycle  and wasted sludge.  Oxygen-enriched gas could be used in
place  of  air  in  the  aeration  tanks   to   improve   overall
performance.   This  would  require  that  the  aeration  tank be
partitioned  and  covered,  and  that  the  air  compressor   and
dispersion system be replaced by a rotating sparger system.  When
concurrent, staged flow and recirculation of gas back through the
                                  104

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liquor  are  employed,  between  90  and 95-percent oxygen use is
claimed.  Although this modification of extended aeration has not
been used in treating poultry  processing  plant  wastes,  it  is
being used successfully for treatment of other wastes.


Advantages-Disadvantages

The  advantages  of  the extended aeration process are that it is
immune  to  shock  loading  and  flow  fluctuations  because  the
incoming raw waste load is diluted by the liquid in the system to
a  much  greater  extent  than  in conventional activated sludge.
Also, because of the long detention time,  high  BOD5  reductions
can  be  obtained.   Other  advantages  of  the  system  are  the
elimination of sludge digestion equipment and the  capability  to
produce  a  nitrified  effluent.   Disadvantages  are  that it is
difficult to remove most of the suspended solids from  the  mixed
liquor  discharged  from the aeration tank; large volume tanks or
basins are required to accommodate the long detention times;  and
operating costs for aeration are high.

Applications

Because  of  the nitrification process, extended aeration systems
are being used by some industries following  anaerobic  processes
or   lagoons   to  produce  low  BOD^  and  low  ammonia-nitrogen
effluents.  They are also  being  used  as  the  first  stage  of
biological treatment, followed by polishing lagoons.


                  Rotating Biological Contactor

Process Description

The  rotating  biological contactor  (RBC) consists of a series of
closely spaced  flat  parallel  disks  which  are  rotated  while
partially   immersed  in  the  waste  waters  being  treated.   A
biological growth  covering  the  surface  of  the  disk  adsorbs
dissolved  organic  matter  present  in  the waste water.  As the
biomass on the disk builds  up,  excess  slime  is  sloughed  off
periodically  and  is  settled  out  in sedimentation tanks.  The
rotation of the disk carries a thin film of waste water into  the
air  where  it  absorbs  the  oxygen  necessary  for  the aerobic
biological activity of  the  biomass.   The  disk  rotation  also
promotes  thorough mixing and contact between the biomass and the
waste waters.  In many ways the RBS system is a  compact  version
of a trickling filter.  In the trickling filter, the waste waters
flow over the media and thus over the microbial flora; in the RBC
system, the biological medium is passed through the waste water.

The system can be staged to enhance overall waste load reduction,
Organisms  on the disks selectively develop in each stage and are
thus particularly adapted to the composition of the waste in that
stage.  The first stages might be used for removal  of  dissolved
                                    105

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organic  matter,  while  the  latter  stages  might be adapted to
nitrification of ammonia.
Development Status

The RBC system was developed  independently  in  Europe  and  the
United  states about 1955 for the treatment of domestic waste; it
found application only in Europe, where there  are  an  estimated
1,000  domestic installations,21  However, the use of the RBC for
the treatment of poultry processing waste is being  evaluated  at
the  present  time.   One  poultry  plant1*  is  reported to have
obtained a 90-percent BOD5 reduction  (from  2,000  to  200  mg/1)
when  treating  the effluent from an air flotation system.  Pilot
scale operating information is  available  on  its  use  on  meat
packing  waste.   The  pilot-plant  studies were conducted with a
four-stage RBC system with four-foot diameter disks*  The  system
was   treating  a  portion  of  the  effluent  from  the  Austin,
Minnesota, anaerobic contact plant used  to  treat  meat  packing
waste.   The  results  showed  a  BOD5  removal  in  excess of 50
percent, with loadings less than 0.037 kg BOD5 per  square  meter
on  an  average  BOD5  influent concentration of approximately 25
mg/1, 2 2

Data from Autotrol Corporation,  one  of  the  suppliers  of  RBC
systems,  revealed  ammonia removal of greater than 90 percent by
nitrification in a multistage unit.   Four  to  eight  stages  of
disks  with  maximum  hydraulic loadings of 61 liters per day per
square meter  (1.5 gallons per day per square foot) of  disk  area
are considered normal for ammonia removal.

A  large  installation  was  recently  completed at the Iowa Beef
Processors plant  in  Dakota  City,  Nebraska,  for  the  further
treatment  of  the  effluent from an anaerobic lagoon.23  No data
are available on this installation, which has been  plagued  with
mechanical problems.


Advantages-Pi sadvantaqes

The  major  advantages  of  the RBC system are its relatively low
first cost;  the  ability  to  obtain  dissolved  organic  matter
reduction   with   the   potential  for  removal  of  ammonia  by
nitrification; and its good resistance to hydraulic shock  loads.
Disadvantages are that the system should be housed, if located in
cold  climates,  to  maintain  high  removal  efficiencies and to
control odors.  This system has demonstrated its  durability  and
reliability  when  used  on  domestic  wastes  in  Europe, and is
currently being tested on poultry processing plant wastes in this
country-
                                   106

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Uses

Rotating biological contactors  could  be  used  for  the  entire
aerobic  biological system.  The number of stages required depend
on the desired degree of treatment  and  the  influent  strength.
Typical   applications  of  the  rotating  biological  contactor,
however,  may  be  for  polishing  the  effluent  from  anaerobic
processes,  and  as pretreatment prior to discharging wastes to a
municipal system.  A BOD5 reduction of 98 percent  is  reportedly
achievable with a four-stage
                    ADVANCED WASTE TREATMENT

                     Chemical Precipitation

Phosphorus  is  an  excellent  nutrient  for  algae  and thus can
promote heavy algae blooms.  As such,  it  cannot  be  discharged
into  receiving  streams,  and  its  concentration  should not be
allowed to build up in a  recycle  water  stream.   However,  the
presence  of  phosphorus is particularly useful in spray or flood
irrigation systems as a nutrient for plant growth.

The  effectiveness  of  chemical   precipitation   for   removing
phosphorus. Figure 13, has been verified in full-scale during the
North  Star  verification  sampling  program  of the meat packing
industry.19  One packing plant operates a dissolved air flotation
system as a chemical precipitation unit and  achieves  95-percent
phosphorus  removal,  to  a  concentration  of  less than 1 mg/1.
Chemical  precipitation  can  be  used  for  primary   (in-plant)
treatment  to  remove  BOD5,  suspended  solids,  and  grease, as
discussed earlier in conjunction with  dissolved  air  flotation.
Also,  it  can  be used as a final treatment following biological
treatment to remove suspended solids in addition to phosphorus.


Technical Description

Phosphorus occurs in waste water streams from poultry  processing
plants   primarily   as   phosphate  salts.   Phosphates  can  be
precipitated with trivalent iron and  trivalent  aluminum  salts.
It  can  also  be  rapidly  precipitated by the addition of lime;
however, the. rate of removal is controlled by  the  agglomeration
of  the  precipitated  colloids  and  by the settling rate of the
agglomerate.15  Laboratory investigation and experience with  in-
piant  operations  have  substantially  confirmed  that phosphate
removal is dependent on pH and that  this  removal  tends  to  be
limited by the solubility behavior of the three phosphate salts —
calcium,  aluminum,  and  iron.   The optimum pH for the iron and
aluminum precipitation occurs in the 4 to 6  range,  whereas  the
calcium  precipitation  occurs  on the alkaline side at pH values
above 9.5^ **

Since the removal of phosphorus is a two-step  process  involving
precipitation  and  then agglomeration, and both are sensitive to
                                  107

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pH, controlling the pH level takes on added significance.   If  a
chemical other than lime is used in the precipitation/coagulation
process,  two levels of pH are required.  Precipitation occurs on
the acid side and coagulation is best carried out on the alkaline
side.   The  precipitate  is  removed  by  sedimentation  or   by
dissolved air flotation.

Polyelectrolytes  are  polymers  that  can  be  used  as  primary
coagulants,  flocculation  aids,  filter  aids,  or  for   sludge
conditioning.   Phosphorus  removal may be enhanced by the use of
such polyelectrolytes by producing a better floe than might occur
without such chemical addition. z*

The chemically precipitated sludge contains  grease  and  organic
matter  in  addition  to the phosphorus, if the system is used in
primary treatment.  If it is used as a post-biological treatment,
the sludge volume will be less  and  it  will  contain  primarily
phosphorus  salts.   The  sludge  from  either  treatment  can be
landfilled.
Development Status

This process is well  established  and  understood,  technically.
However,  its  use  on  poultry  processing  plant  waste waters,
normally  as  a  primary  waste  treatment  system,  is  limited;
although, its use may grow as more stringent effluent limitations
are imposed.


Problems and Reliability

As  indicated  above,  the  reliability  of  this process is well
established; however, it  is  a  chemical  process  and  as  such
requires  the  appropriate control and operating procedures.  The
problems that can be encountered in operating  this  process  are
frequently  the  result  of a lack of understanding or inadequate
equipment.  Sludge disposal is not  expected  to  be  a  problem,
although  the  use  of  polyelectrolytes  and their effect on the
dewatering properties of the sludge are open to some question  at
the  present  time.  In addition, the use of the recovered sludge
as a raw material for rendering may be less desirable as a result
of chemical addition.

                           Sand Filter

A slow sand filter is a specially prepared bed of sand  or  other
mineral  fines  on  which doses of waste water are intermittently
applied and from which effluent is removed by  an  under-drainage
system   (Figure  14);  it  removes  solids  from  the waste water
stream.  A variety of filters can be used to remove the solids in
a  treated  wastewater:  intermittent  sand  filters,  slow  sand
filters,  rapid  sand  filters,  and  mixed-media  filters,  BOD5
removal occurs primarily as a function of the  degree  of  solids
removal.  The effluent from the sand filter is of a high quality.
                                    108

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                                   Float
Primary
or
oeconoary 	 •?
Treatment
Effluent

pH
Ajustment




Chemical
Addition

N

/
^
Air
Flotation
System

Partial

ireatea
Effluent
                                          V
                                        Sludge
                                          to
                                       Disposal
Figure 13.  Chemical  Precipitation
Primary or
Secondary
Treatment
 Effluent
        Dosing
         Tank

                            Chlorination,
                              Optional	
                            for  Odor Control
Filter
                           A
                                            V
                     V
                Surface     Back
                 Clean  u   Wash

                  to Regenerate
                                                                 > Treated
                                                                 Effluent
  Figure  14.   Sand Filter Syst
                                                em

-------
A  summary  of  available  information  indicates  that  effluent
suspended solids concentrations of less than 10 mg/1 can be  met.
Although  the  performance  of  a  sand  filter is well known and
documented, it is not in common use in the meat products industry
because use of refinements of this type has not  been  needed  to
reach current waste water limitations.

A rapid sand filter may operate under pressure in a closed vessel
or  may be built in open concrete tanks.  It is primarily a water
treatment device and thus would be used  as  advanced  treatment.
Mixed-media  filters  are  special versions of rapid sand filters
that permit deeper bed-penetration by gradation of particle sizes
in the bed.  Up-flow filters are  also  special  cases  of  rapid
filters.
Technical Description

The  slow  sand filter removes solids primarily at the surface of
the filter.  The rapid sand filter is operated to allow a  deeper
penetration  of  suspended  solids  into the sand bed and thereby
achieve solids removal through a greater  cross  section  of  the
bed.   The  rate  of  filtration of the rapid filter is up to 100
times that of the slow  sand  filter.   Thus,  the  rapid  filter
requires  substantially  less area than the slow filter; however,
the cycle time averages about 2H hours in comparison with  cycles
of  up  to  30  to  60 days for a slow filter,26  The larger area
required for the latter means a higher  first  cost.   For  small
plants,  the  slow sand filter can be used as advanced treatment.
The rapid sand filter, on the other hand, can be  more  generally
applied  following  biological  treatment.   However,  if used as
biological treatment it would tend to clog  quickly  and  require
frequent  backwashing,  resulting in a high water use.  This wash
water would also need treatment prior to  discharge  particularly
it  the  rapid  sand  filter  were  used  in biological treatment
applications with only conventional solids  removal  upstream  in
the plant.

The  rapid  filters  operate essentially unattended with pressure
loss controls and piping  installed  for  automatic  backwashing.
They are contained in concrete structures or in steel tanks.


In  a  rapid  sand filter, as much as 80 percent of the head loss
can occur in the upper few inches of the filter.  One approach to
increase the effective filter depth is the use of more  than  one
media  in  the  filter.   Other filter media have included coarse
coal, heavy garnet or ilmenite media, and sand.2*   There  is  no
one  mixed  media design which will be optimum for all wastewater
filtration problems.  As an example, "removal of small quantities
of high-strength biological floe often found in activated  sludge
effluents  may  be  satisfactorily  achieved by a good dual media
design.  With a weaker floe  strength  or  with  an  increase  in
applied  solids loading, the benefits of the mixed, tri-media bed
become more pronounced.nz*
                                   110

-------
Although a  mixed-media  filter  can  tolerate  higher  suspended
solids loadings than can other filtration processes, it still has
an  upper limit of applied suspende
-------
                    Table 14.*. rffluent- Oualitv from Conventional
               filtration of Carious  THologicailv Treated Wa
Influent
Source
Activated F!ludcro

Activated Sludae
"xtended
Deration plus
settling
Trickling
^ilter
Activated Sludge
with Clarifier
Contact
Stabilisation
(ra*T waste
includes
cannerv)
miscellaneous


rilter
TYPE
nrvwit"
mixed, media
multi-media
pressure,
multi-media

nravitv,
sand
multi-media

mixed media




sand
(S!CT-* and
ran id)
nilter Influent (mg/1)
BOD TSS
15-20 10-25

11-50 28-126
7-36 30-2180


15-130 8-75

18
(AVE)
_ —




10-50 15-75


'liter 'Pf fluent (mq/1) Reference
pnn. TSS
4-3 0 2-5 70

3-3 1-17 70
1-4 1-20 70


2-74 " 1-27 ^3, 65

2.4 67
(AVE)
2-4 2-8 68




2-6 3-10 62, 64,
73

Trickling
pilter v\i
Nitrification
sand
3-7
57
   *See also, irerformance data in references  24,  25,  65,  66,  and

-------
Problems and Reliability

The reliability of all principal types ot  filters  seems  to  be
well  established by lonq-term use as a municipal waste treatment
system.  When the sand filter is  operated  intermittently  there
should  be  little  danger  of  operating  mishap  with resultant
Discharge of untreated effluent or poor  quality  effluent.   The
need  for  bed  cleaning  becomes  evident  with the reduction in
quality of the effluent or in the increased cycle time,  both  of
which  are  subject to monitoring and control.  Operation in cold
climates is possible as long as the appropriate adjustment in the
surface of the bed has been made to prevent the bed from clogging
due to freezing water.

With larger sized slow sand filters, the labor in maintaining and
cleaning  the  surface  should  receive  adequate  consideration.
Cleanup  of the rapid sand filter requires backwashing of the bed
of sand with a greater quantity of water than used for  the  slow
sand  filter.   Backwashing is an effective cleanup procedure and
the only constraint is to  minimize  the  washwater  required  in
cleanup,  since  this  must  be  disposed  of in some appropriate
manner other than discharging it to a stream,  Chlorination, both
before and after sand filtering, particularly in the use of rapid
filters, may be desirable to minimize or eliminate potential odor
probleirs and slimes that may cause clogging.

The  rapid  sand  filter  has  been  used  extensively  in  water
treatment  plants  and in municipal sewage treatment for advanced
treatment; thus, its use  in  advanced   treatment  of  biological
treated  effluents from poultry processing plants appears to be a
practical method of reducing EOD5 and suspended solids to   levels
below those expected from conventional biological treatment.

                    Microscreen-Microstrainer
A  microstrainer  is  a  filtering  device  that uses a fine mesh
screen on a partially submerged rotating drum to remove suspended
solids and thereby reduce the BODjS associated with those  solids,
as  shown  in Figure 15.  The microstrainer is used as a advanced
treatment following the removal of most of the  solids  from  the
waste  water  stream,  and   suspended  solids  and BOD5 have been
reduced to 3 to 5 mg/1 in applications on municipal  waste.IS  As
mentioned   earlier,   one   poultry   processing   plant   using
microscreens as advanced treatment consistently achieved  a  BOD5
in the effluent of less than 15 mg/1 and frequently below 5 mg/1.
The effluent quality obtained by the microstrainer at the poultry
processing  plant  is  consistent  with  data  reported  by other
situations in which  micrcstrainers  have  been  used  to  remove
solids   from  biological  effluents.   The  percent  removal  of
suspended solids by a microstrainer are related to  the  size  of
the  aperture of the screen.  Fifty to 60-percent removals can be
anticipated with  a  23-micron  strainer  and  40  to  50-percent
removals  with a 35-micron strainer.24 The microstrainer effluent
quality from a  number  of   studies  indicated  suspended  solids
                                 113

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Secondary
Treatment
 Effluent


Micro-
Screen
v
f
Bo<

ckwash
Clear
to
Screen/Strainer
Tertiary
                                                     Effluent
                 Figure  15.  Microscreen/Microstrainer

-------
concentrations  of 6 to 8 mg/1 when activated sludge effluent was
tested, and 15 to 40 mg/1 when a trickling  filter  effluent  was
treated.z*
Technical De scription

The  microstrainer  is  a  filtration device in which a stainless
steel microfabric is used as the  filtering  medium.   The  steel
wire cloth is mounted on the periphery of a drum which is rotated
partially  submerged  in  the  waste water.  Backwash immediately
follows the deposition of  solids  on  the  fabric,  and  in  one
installation,  this is followed by ultra-violet light exposure to
inhibit microbiological growth.  The  backwash  water  containing
the  solids  amounts to about 3 percent of the waste water stream
and must be disposed of by recycling to the biological  treatment
system.28   The  drum is rotated at a minimum of 0.7, and up to a
maximum of 4.3 revolutions per  minute.   The  concentration  and
percentage  removal  performance  for microstrainers on suspended
solids and BODji appear to be approximately the same as  for  sand
filters.
Development Status

While  application  of microscreens for filtration is more recent
than that of conventional filters, there is  general  information
available  on  the  performance  of  microstrainers  and on tests
involving the use of them.  In addition to  its  use  on  poultry
processing  waste, there has been a substantial increase in full-
scale applications at municipal facilities.  As with conventional
filters,  the  requirements  for  effluent   quality   have   not
necessitated  such  installations  in  the  past.   The  economic
comparisons  between  sand   filters   and   microstrainers   are
inconclusive;   the   mechanical   equipment   required  for  the
microstrainer may be  a  more  relevant  factor  than  the  space
requirement  for  the sand filter at the present time.  Table 14B
provides a brief summary of the general performance  achieved  by
microstrainers on biologically treated wastewater.


Problems and Reliability

The   reported  performance  of  the  microstrainer  fairly  well
establishes the reliability of the  device  and  its  ability  to
remove  suspended  solids  and  associated  BODf>.   operating and
maintenance problems have not been  reported;  this  is  probably
because, in large part, of the limited use of the device in full-
scale  applications.  As a mechanical filtration device requiring
a drive system, it would  have  normal  maintenance  requirements
associated  with  that kind of mechanical equipment.  As a device
based on microopenings in a  fabric,  it  would  be  particularly
intolerant to any substantial degree of grease loading.


                                 115

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            Table 14B.  Performance of Microstrainers
    in Tertiary Treatment of Biologically Treated Wastewater


Influent (mg/1)	       Effluent (mg/1)	Reference
BOD
15-20
10-30
-
15-25
TSS
20-25
10-40
6-54
15-30
BOD
3-5
3-8
-
4-5
TSS
6-8
3-10
2-14
3-7

24
73
70*
poultry pi a
  *Data from 22 municipal installations including several  with
   wasteload contributions from unidentified industrial  sources.
                                 116

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                        Nitrogen control


Nitrification

Nitrification is the biological conversion of nitrogen in organic
or  inorganic  compounds  from  a more reduced to a more oxidized
state.  In the field of water  pollution  control,  nitrification
usually  is referred to as the process in which ammonium ions are
oxidized to nitrite  and  nitrate  sequentially.   When  aeration
systems   are  used  to  treat  an  industrial  wastewaterr  some
nitrification and ammonia stripping  can  be  expected  to  occur
naturally  and  thus  reduce  the  quantity  of ammonia requiring
further removal.  This "incidental" treatment has  been  observed
for  treated effluents from several types of meat products plants
where concentrations of about 10 to 50 wg/1 of ammonia have  been
found,  while  partially  treated  wastes  have concentrations in
excess of 100 mg/1.  Ammonia removal is becoming  more  important
since  it  is  recommended  that  the concentration of un-ionized
ammonia  (NH3) in surface water be no greater than  0.02  mg/1  at
any  time  or  place.   Because  ammonia  may  be  indicative  of
pollution, it is recommended  that  ammonia  nitrogen  in  public
water supply sources not exceed 1.5 mg/1.*2

Technical Description

Nitrification  can be used to reduce the ammonia concentration of
wastewaters.  Figure 16  is  a  schematic  of  the  nitrification
process.    The  equations  following  the  figure  indicate  the
nitrification sequence and organisms involved.
Adequate process design and operating control are  necessary  for
consistent   results.   Factors  that  affect  the  nitrification
process   include   concentration   of   nitrifying    organisms,
temperature,   pH,   dissolved   oxygen  concentration,  and  the
concentration  of  any  inhibiting  compounds.*3  The  nitrifying
organisms  of  significance  in waste management are autotrophic,
with Nitrosomes and Nitrobacter being the major bacterial  genera
that  are  involved.   Nitrifying  bacteria are ubiquitous in the
soil although they may not be part of untreated wastes.

Nitrifying organisms are aerobic and  adequate  dissolved  oxygen
(DO)  in  the  aeration  system  is necessary.  DO concentrations
should be above 1 to 2 mg/1 to assure  consistent  nitrification.
Nitrification  is  affected  by  the  temperature  of the system.
Available  information   provides   conflicting   data   on   the
performance   of   nitrification  systems  at  low  temperatures.


                                  117

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00
Secondary
Treatment
Effluent
Aeration
System



i

\ "

Anaerobic ,
Pond *


Aeration ^ Tertiary
Cell > Treated

Effluent
Carbon
Source,
e.g. Methanol
                                           Figure  16.   Nitrification/Denitrification
Nitrification:




     NH3 + 02
     2N02~ + 02
                                                       N02~  + H30     (Nitrosomonas)




                                                         2NO "   (Nitrobacter)
                                Denitrification (using methanol as  carbon source)
     6H  + 6N03~ + 5CH3OH
                                                                 5C02 + 3N2 + 13H20
                                     Small amounts of  N20 and NO are also formed




                                                              (Facultative heterotrophs)

-------
Although detailed studies are lacking, it should be  possible  to
achieve  nitrification  at  low  temperatures  and compensate for
slower nitrifying organism growth rates by maintaining  a  longer
solids  detention time and hence larger nitrifying active mass in
the system.**

The optimum pH for nitrification of  municipal  sewage  has  been
indicated  to  be between 7.5 and 8.5.  Nitrification can proceed
at low  pH  levels  but  at  less  than  optimum  rates.   During
nitrification,  hydrogen  ions are produced and the pH decreases,
the magnitude  of  the  decrease  being  related  to  the  buffer
capacity  of the system.  A decrease in pH is a practical measure
of the onset of nitrification.

High concentrations of un-ionized ammonia  (NH3)   and  un-ionized
nitrous  acid (H N02) can inhibit nitrification.   These compounds
can be in the influent wastewater or can be generated as part  of
the  nitrification  process.   The  concentrations  of un-ionized
ammonia  and  nitrous  acid  that  are   inhibitory;   and,   the
operational   approaches  to  avoid  such  inhibition  have  been
documented.**  Using these approaches, it should be  possible  to
operate  nitrification  systems  that  produce consistent results
even with wastewaters having high nitrogen concentrations.

Development status

    While research on nitrification  has  been  conducted  for  a
number  of  years,  most  pilot  and full-scale studies have been
initiated since 1970.  Even though there has  been  a  relatively
short  time  frame of evaluation, nitrification is already a very
readily described process for which treatment system designs  can
be  implemented.  Most of the applications have been on municipal
effluents, but  concentrations  of  ammonia  in  these  effluents
ranged  between  20 mg/1 and 800 mg/1.  Ammonia concentrations in
biologically treated effluents from various  types  of  meat  and
poultry  packing  and  processing plants have been found to range
between 10 mg/1 and 200 mg/1 or more, and thus  fall  within  the
limits  of  the nitrification investigations cited below in Table
14C.  Like any other "advanced" level of treatment, nitrification
requires more operational attention than has generally been given
to simple biological treatment,  but  the  applicability  of  the
process  to  all  types  of  meat  product effluents appears very
reasonable.

Problems and Reliability

    As discussed above, emphasis on nitrification as a  treatment
process  has  been  relatively  recent.   Except  for  incidental
ammonia removal facilities, nitrification processes have not been
specifically applied in this industry.  A pilot facility  may  be
necessary  to derive design and operating requirements before any
full-scale installations  are  constructed.   Water  temperature,
particularly  below  10°C, is an apparent constraint for which an
increase in sludge age  or  solids  retention  time  (via  sludge
recycle)  has  been shown to compensate.  Maintenance of adequate
                                   119

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                       14r. Selected "esults  for
Nitrogen Control—
'•'ode
Extented aeration (N)
Clarification (ON)
Denitrif ication "Hewer
Nitrification
Single ?tage (DM)
Rotating nisc(N)
Trickling rilter Totter (N)
derated sludge and
anaerobic reactor (ON)
Breakpoint 00
chlorination
Activated Sludge (H)
Parameter (s)
Measured
Total Kjeldahl
Nitrogen
Tx>tal nitroaen
Armenia
Anmonia
Total nitrogen
Ammonia
Armonia
nitrates
Arrroonia
Aimonia
Tf fluent
Toncentration (mg/1)
0.5-10.0
5.0
0.8-1.2
1.7 June-
1.9 Januarv
3.8-5.9
0.3-1.2
1.6-2.5
1.2-1.9
0.0-1.5
0.0
1.0
0.0-2.7

60
47
47
47
47
57£/
53
71
72
—''Jote  (N) refers to nitrification svsten and  (DN) refers  to nitrification-
  denitrification

li'Influent anmonia concentrations ranae of  450-800 nq/1

£'"*anqe of data for 18 month neriod; test site in Michigan with seasonal
  data collected for annroximatelv two T-teeks each season.

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dissolved oxygen levels is  also  important  since  nitrification
activity  effectively  ceases  at  DO levels below 1.0 mg/1.,  The
process is  relatively  delicate  and  should  require  attentive
operation,

                  Nitrification/Denitrification

This  two-step  process  of  nitrification  and  denitrification,
Figure 16, is of primary importance for removal of  the  residual
ammonia  and  nitrites-nitrates  in biological treatment systems.
Removal  of  the  above  soluble  nitrogen  forms  is   virtually
complete, with the nitrogen gas as the end product.  This process
differs  from  ammonia  stripping  and  nitrification in that the
latter processes convert or remove only the ammonia content of  a
wastewater.   Table  me  shows  a summary of results in removing
both ammonia and other nitrogen from wastewaters.

Technical Description

As described in an earlier section, nitrification is carried  out
under  controlled  process  conditions by aerating the wastewater
sufficiently to assure the conversion  of  the  nitrogen  in  the
wastewater  to  the  nitrite-nitrate  forms.  The denitrification
process reduces the oxidized  nitrogen  compounds   (nitrites  and
nitrates)  to  nitrogen  gas and nitrogen oxides thereby reducing
the nitrogen content of the wastewater as the gases  escape  from
the liquid.

Denitrification  takes  place in the absence of dissolved oxygen.
Additional important factors  affecting  denitrification  include
carbon source, and temperature.  Denitrification is brought about
by   heterotrophic   facultative   bacteria.    Generally,   high
denitrification rates require the  addition  of  a  biodegradable
carbon  source  such  as  sugar,  ethyl  alcohol, acetic acid, or
methanol.   Methanol  is  the   least   expensive    and   performs
satisfactorily.  Investigators  working on this process have found
that  a   30-percent  excess  of  methanol over the  stoichiometric
amount is required.2*,30

Denitrification does not take place until  the  dissolved  oxygen
concentration  of  the  wastewater  is  near  or  at  zero.   The
organisms responsible for denitrification are ubiquitous and  can
adapt to  pH levels within the range of about 6.0 to 9.0.  As with
any  biochemical  process, denitrification exhibits a temperature
dependency, although within the range  of  20°C  to 30°C  little
effect  has  been  observed.    Denitrification activity decreased
when the  temperature decreased  to  10°C.  Denitrification  can  be
operated  at  low  temperatures by  designing  systems with long
solids retention times  (SRT).   For  denitrification  systems,  an
SRT  of   at least 3 to  a days at 20°C and 30°C and  8 days at 10°C
has  been recommended.*3   Nitrate   reduction    efficiency   in
denitrification  can  be  controlled  by adjusting  the SRT of the
process to assure adequate numbers of denitrifying  organisms  and
adequate   denitrification   rates  as  environmental  conditions
change.


                                   121

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In a  sequential  nitrification/denitrification  process  (Figure
16) ,  the wastewater from the denitrification step may be sent to
a second aeration  basin  following  denitrification,  where  the
nitrogen  and  nitrogen oxide are readily stripped from the waste
stream as gases.  The sludge from each stage is settled  and  re-
cycled  to  preserve  the organisms required for each step in the
process.  The processes of nitrification and denitrification  can
occur  simultaneously  in  aeration systems in which both aerobic
and anaerobic portions occur.
Development Status

Nitrification/denitrification has not  been  applied  to  poultry
processing wastewaters as yet.  The process has been evaluated in
a number of bench and pilot-scale studies on a variety of wastes.
Further  demonstration  on  a  plant  scale  will  establish  the
potential of the process.43,*5 Anaerobic processes  evaluated  as
part  of  the  denitrification  sequence  have included anaerobic
ponds,  an  anaerobic  activated  sludge  system,  and  anaerobic
filters.    Efficient   nitrogen   removals   from   agricultural
subsurface drainage water were  accomplished  with  an  anaerobic
filter.   In Germany, the successful elimination of nitrogen from
sewage and digester supernatant was achieved by first  nitrifying
the  wastes  and then denitrifying in a separate vessel.  Two and
three sludge systems have been  shown  to  be  feasible  for  the
nitrification/denitrification process.  A pilot model of a three-
stage  system  using this process was developed at the Cincinnati
Water Research Laboratory of  the  EPA  and  is  being  built  at
Manassas,  Virginia.31 Observations of treatment lagoons indicate
that the suggested reactions are occurring  in  present  systems.
Also,  Halvorson32  reported that Pasveer achieved success in de-
nitrification by carefully controlling the reaction  rate  in  an
oxidation  ditch,  so  that  dissolved oxygen levels drop to near
zero just before the  water  is  reaerated  by  the  next  rotor.
Denitrification  of animal wastes has been evaluated and shown to
be feasible,43 *s  Depending upon how a biological system such as
an oxidation ditch is operated, the nitrogen loss can range  from
30 to about 90 percent.**


Problems and Reliability

It would appear that there would be no exceptional maintenance or
residual  pollution problems associated with this process in view
of the mechanisms suggested for its implementation at this  time.
For   some  of  the  newer  concepts,  i.e.,  denitrification  by
fluidized  bed  reactors,   operational   difficulties   due   to
biological matting of the carbon filter bed have been encountered
in  bench  scale  tests.  These difficulties may prove negligible
under field conditions, since  continuing  new  inputs  of  biota
would  enhance  the  likelihood  of  a balance in growth factors.
Completely mixed reactors with methanol  addition  appear  to  be
favored from the standpoints of operational control and long-term
reliability  in  nitrogen  removal.   However,  a  final aeration


                                   122

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chamber may be required to offset increases in effluent  BOD  due
to  methanol  leakage  from the denitrification reactor.  As with
nitrification, sludge return has also been shown to assist system
stability in the denitrification mode.47

                        Ammonia Stripping

Ammonia  stripping  is  a  physical  process  and  amounts  to  a
modification of the simple aeration process for removing gases in
water.  Figure  17.   Following pH adjustment, the waste water is
fed to a packed tower and allowed to flow down through the  tower
with  a countercurrent air stream introduced at the bottom of the
tower flowing upward  to  strip  the  ammonia.   Ammonia-nitrogen
removals  of  up to 98 percent and down to concentrations of less
than 1 mg/1 have been achieved in experimental ammonia  stripping
towers.
Technical Description

Because  of  the  chemistry of ammonia, the pH of the waste water
from a biological treatment system should be adjusted to  between
11 and 12 and the waste water is fed to a packed or cooling tower
type  of  stripping  tower.*3  As  pH  is shifted to above 9, the
ammonia is present as a soluble gas in the  waste  water  stream,
rather  than as the ammonium ion.  Ammonia-nitrogen removal of 90
percent  has  been  achieved  on  a   municipal   effluent   with
countercurrent  air  flows  between  1.8 and 2,2 cubic meters per
liter  (250 and 300 cubic feet per gallon) of waste  water  in  an
experimental  tower  with  hydraulic loadings between 100 and 125
liters per minute per square meter  (2.5 and 3 gallons per  minute
per  square foot).  The best performance was achieved with an air
rate of 5.9 cubic meters per liter  (800 cubic  feet  per  gallon)
and  a hydraulic loading of 33 liters per minute per square meter
(0.8  gallons  per  minute  per   square   foot);   the   ammonia
concentration  was  reduced  to less than one part per million at
98-percent removal.  The  high  percentage  removal  of  ammonia-
nitrogen  is  achieved only at a substantial cost in terms of air
requirements and stripping tower cross-sectional area.24


Development Status

The ammonia stripping process  (using both steam and  air  as  the
stripping  medium)  has  been  practiced  on  "sour water" in the
petroleum refinery industry.   The  only  significant  difference
between  the  petroleum  refinery application and that on poultry
processing  waste  would  be  the  comparatively  small  size  of
stripping  tower  required  for  poultry  plants, compared to the
refinery.  The air stripping of ammonia from biological  effluent
is  reported  primarily  on  a  pilot  plant  basis using various
equipment.51  Two large-scale installations of ammonia  stripping
of   lime-treated  waste  water  are  reported  at  South  Tahoe,
California, and Windhoek,  South  Africa.15,24  The  South  Tahoe
ammonia  stripper  was  rated at 14.2 M liters per day  (3.75 MGD)
                                    123

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and was essentially constructed as  a  cooling  tower  structure,
rather  than  a.s a cylindrical steel tower which might be used in
smaller sized plants.7*

Thus, although there is no reported use of ammonia  stripping  on
poultry  processing  plant  waste,  the technology is technically
well established and implementation, when limitations require it,
would be a possible alternative, particularly for well-stabilized
biological effluents.

Problems and Reliability

The reliability of this process  has  been  found  reasonable  in
petroleum  refinery  applications of the process over many years.
Although the source of the ammonia may be different and there may
be other contaminants in the water stream, this should not affect
the established reliability of this process.  The  experience  of
other  users  of  the  process  will  have  identified  potential
problems, and, presumably, the solutions for these  problems  can
be  found.   Among  the  maintenance  requirements would be those
normally associated with the  mechanical  equipment  involved  in
pumping the waste water to the top of the tower where the feed is
introduced to the tower, and in maintaining the air blowers.  The
tower  fill would undoubtedly be designed for the kind of service
involved in treating a waste water stream that has some potential
for fouling.  Problems with temperature  and  tower  scaling  are
also ;  documented.    Recent   advances  in  possible  anti-scale
chemicals appear promising,50 It  has  also  been  observed  that
efficiency  losses  due  to  low  temperature  can  be  at  least
partially overcome by breakpoint  chlorination,  by  housing  the
stripping  tower,  or  heating the water or air with waste steam.
The most recent  advance  in  the  process  includes  an  ammonia
recovery step and preliminary results indicate that most problems
with stripping towers have been overcome,74

                     Breakpoint Chlorination

When  wastewater  containing  ammonia is treated with chlorine, a
chemical  reaction  toward  the  formation  of   chloramines   is
observed.    Further   chlorination  to  the  "breakpoint"   (free
chlorine  residuals  predominate)  converts  the  chloramines  to
nitrogen gas which is lost to the atmosphere.

Technical Description

A detailed discussion of the chemistry of breakpoint chlorination
is   readily  found  in  numerous  textbooks  and  references  on
disinfection.*3,74 In summary, chlorine is added   (as  a  gas  or
liquid)  to  wastewaters containing ammonia in amounts sufficient
to cause the release of nitrogen gas.  For each part of  ammonia,
about  nine  parts of chlorine are required to drive the chemical
reactions from  monochloramines  through  to  nitrogen  gas.   At
proper  chlorine feed rates, a contact time of 30 minutes or less
is necessary.
                                    124

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Development Status

Breakpoint chlorination is a well-understood and  well-documented
technology.   Applications have centered on advanced treatment of
biological municipal wastes, although the concept has been  found
to  be  useful  as a "polishing" mode in conjunction with ammonia
stripping.  It appears  from  the  literature  that  the  process
offers  a  viable  alternative  for  ammonia  control for ammonia
concentrations  as  are  encountered  in   municipal   biological
effluents.

Problems and Reliability

Under  low pH (less than 6.0) conditions, chlorination of ammonia
may produce nitrogen trichloride which is  highly  odorous.   The
removal  of  ammonia  is  not  adversely  affected  if it becomes
necessary to add a  base  (sodium  hydroxide)  to  overcome  acid
conditions.   Under field conditions described in the literature,
the natural alkalinity of the wastewater being treated proved  to
be  sufficient  to  preclude  depression  of  pH  below 6.0.  The
process operates equally well in the temperature range of 5°C  to
40°C; more chlorine may be needed at lower temperatures.  Process
efficiencies consistently range between 95 and 99 percent and the
process  is  easily  adapted  to  complete automation which helps
assure  quality  and  operational  control.   Excessive  use   of
chlorine   can   result  in  substantial  relative  increases  in
dissolved solids  (choride salts) in effluents.


                     Spray/Flood Irrigation

A no discharge level for poultry processing waste  water  can  be
and  is being achieved by the use of spray or flood irrigation on
relatively flat land, surrounded by dikes to prevent  runoff.   A
cover  crop  of  grass  or  other vegetation is maintained on the
land.  Specific plant situations may preclude the installation of
irrigation  systems;  however,  where  they  are  feasible,   the
economics  can be very favorable and serious consideration should
be given to them.


Technical Description

Wastes are disposed of in spray or flood  irrigation  systems  by
distribution  through  piping  and  spray nozzles over relatively
flat terrain or by the pumping and disposal  through  the  ridge-
and-furrow  irrigation  systems  which  allow  a certain level of
flooding on a given plot of  land. Figure  18.   Pretreatment  for
removal  of  solids is advisable to prevent plugging of the spray
nozzles, or deposition in the  furrows  of  the  ridge-and-furrow
system,  or  collection of solids on the surface, which may cause
odor problems or clog the soil.  Therefore, the BOD5 will usually
have already been reduced in preliminary treatment  (primary  plus
some   degree   of   biological   treatment)  upstream  from  the
distribution system.
                                   125

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                        Secondary
                        Treatment
                        Effluent
    pH
Adjustment
Ammonia
Stripping
  Tower
                                                                                      Treated
                                                                                      Effluent
                                            Figure 17.  Animonia Stripping
ro
Primary,
Secondary
or
rui nui -*
Tertiary
Treatment
Effluent

Molding
Basin




Pumping
System

N.


Application
Site


                                                                                        V
                                                                                    Grass or
                                                                                    Hay Crop
                                           Figure 18.  Spray/Flood  Irrigation System

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In flood irrigation, the waste loading in the effluent  would  be
limited  by  the  waste  loading tolerance of tho particular crop
being grown on the land,  or  it  may  be  limited  by  the  soil
conditions or potential for vermin or odor problems.

Waste  water  distributed in either manner percolates through the
soil and the organic matter in the waste undergoes  a  biological
degradation.   The liquid in the waste stream is either stored in
the soil or leached to a groundwater aquifer and discharged  into
the  groundwater.   Approximately  ten  percent of the waste flow
will  be  lost  by  evapotranspiration   (the   loss   caused   by
evaporation to the atmosphere through the leaves of plants).29

Spray  runoff  irrigation  is  an alternative technique which has
been tested on the waste  from  a  small  meat  packer33  and  on
cannery  waste.29   with  this technique, about 50 percent of the
waste water applied to the soil  is  allowed  to  run  off  as  a
discharge  rather  than  no  discharge,  as  discussed here.  The
runoff or discharge from this type of  irrigation  system  is  of
higher quality than the waste water as applied, with BOD5 removal
of  about  80  percent; total organic carbon and ammonia nitrogen
are about 85 percent reduced, and phosphorus is about 65  percent
reduced.

The  following  factors  will  affect the ability of a particular
land area to absorb waste water:  1) character of  the  soil,  2)
stratification  of  the soil profile, 3) depth to groundwater, 4)
initial moisture content, and 5) terrain and ground cover.29

The potentially greatest concern in the use of  irrigation  as  a
disposal  system  is  the  total  dissolved  solids  content  and
particularly the salt content of the waste water.  A maximum salt
content of 0.15 percent is suggested  in  the  literature.   Some
plants  may  require dilution upstream from the irrigation system
to reduce the dissolved solids and the salt content to acceptable
levels for continuing application of the  waste  water  on  land.
However,  the  average  plant  should  have no problem with salt,
since the average salt content of poultry processing waste waters
is  about  a  factor  of  fourteen  less  than  the  literature's
suggested limit of 0.15 percent.

An  application  rate  of up to 330 liters per minute per hectare
(35  gallons  per  minute  per  acre)  has  been   suggested   in
determining the quantity of land required for various waste water
flows.   This  amounts  to almost 5 cm  (2 inches) of moisture per
day, and is relatively low in comparison with  application  rates
reported  in the literature for various  spray irrigation systems.
However, soils vary widely in their  percolation  properties  and
experimental  irrigation  of a small area is recommended before a
complete system is built.  In this report, land requirements were
based on 2.5 cm  (1.0 inch) applied  per  operating  day  for  six
months   of   the   year  with  lagoon  storage  for  six-months'
accumulation of waste water.
                            127

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If poultry processing plant waste waters were being used  as  the
sole  nitrogen  source  for  corn  growth, the waste waters would
probably have to contain 250 to 500  mg/1  nitrogen.   For  lower
nitrogen  concentrations, the corn crop would probably be damaged
by flooding or by heavy overWatering  before  the  corn  received
sufficient  nitrogen from the waste waters.  This is based on the
assumptions that one bushel of ccrn requires 454 gm (1 pound)   of
nitrogen,  that  the  yield  is 120 bushels of corn per acre,  and
that the corn would require from 25 to 75 cm (10 to 30 inches)  of
water per season.3*  This water rate amounts to  3.1  to  9.5   cm
(1.2  to  3.7  inches)  of water per two weeks, over a four-month
season.

The economic benefit from spray irrigation is  estimated  on  the
basis  of  raising  two  crops  of grass or hay per season with a
yield of 13.4 metric tons of dry matter per hectare (six tons per
acre) and valued at $22 per metric  ton   ($20  per  ton).   These
figures  are  reportedly  conservative  in terms of the number of
crops and the price to be expected from a grass or hay crop.  The
supply and demand sensitivity as well as transportation  problems
for  moving  the crop to a consumer all militate against any more
optimistic estimate of economic benefits.35

Cold climate uses of spray irrigation  may  be  subject  to  more
constraints  and  have  greater  land  requirements  than  plants
operating in more temperate climates.  However, a meat packer  in
Illinois  reportedly  operated an irrigation system successfully.
Research indicates that wastes have been  successfully disposed of
by spray irrigation from a number of other industries.29   Plants
located  in  cold climates or short growing areas should consider
two crops for spray irrigation.  One could be a  biological  crop
such  as  corn  and the other a grass crop.  The grass crop could
tolerate heavier volume loadings without  runoff and erosion,  and
also  would  extend  the  irrigation  season from early spring to
possibly late November.  Corn, although   a  more  valuable  crop,
tolerates irrigation in cold climate areas only during the summer
months.

North  Star  found  in  its  survey  of   the  poultry,  meat,  and
rendering industries that the plants located in the arid  regions
of  the  Southwest  were  most  inclined  to  use  spray or flood
irrigation systems.


Problems and Reliability

The long-term reliability of spray or flood irrigation systems is
a function of the ability of the soil to  continue to  accept  the
waste,  and  thus  reliability remains somewhat open to question.
Problems in maintenance are  primarily  in  the  control  of  the
dissolved  solids  level  and salinity content of the waste water
stream and  also  in  climatic  limitations  that  may  exist  or
develop.  Many soils may be improved by spray irrigation.
                              128

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                          Ion Exchange

Ion  exchange,  as  a  advanced  waste  treatment,  is  used as a
deionization process in which specific ionic species are  removed
from  the  waste  water stream. Figure 19,  Ion exchange could be
used to remove salt (sodium chloride) or nutrients  (ammonia) from
waste waters.  Ion exchange resin systems have been developed  to
remove  specific  ionic  species, to achieve maximum regeneration
operating efficiency, and to achieve a desired effluent  quality.
In  the  treatment  of  poultry  processing  waste,  the  desired
effluent quality would be a waste water with a salt concentration
of less than 300 mg/1.  Ion exchange systems are  available  that
will  remove  up  to  90 percent of the salt in a water stream.15
They can also be used to remove nitrogen.75


Technical Description

The deionization of water by means of ion exchange resin involves
the use of both cation and anion exchange resins in  sequence  or
in comhina
tion to remove an electrolyte such as salt.

                    RSO3H * NaCl         RSO3Na + HC1
                    R-OH + HCL           R-C1 + H2O

                    where R represents the resin.

The normal practice in deionization of water has been to make the
first  pass through a strong acid column, cation exchange resins,
in which the  first  reaction  shown  in  the  equations  occurs.
Effluent  from  the  first column is passed to a second column of
anion exchange resin to remove the acid formed in the first step,
as indicated in the second reaction.  As  indicated  in  the  two
reactions,  the  sodium  chloride ions have been removed as ionic
species.  A great  variety  of  ion  exchange  resins  have  been
developed over the years for specific deionization  objectives for
various water quality conditions.

Waste   water   treatment  with  ion  exchange  resins  has  been
investigated and attempted for over  40  years;  however,  recent
process developments in the treatment of biological effluent have
been  particularly  successful in achieving high-quality effluent
at reasonable capital and operating costs.  One such process is a
modification of the Rohm and  Hass,  Desal  process.15   In  this
process  a  weak  base  ion  exchange  resin  is converted to the
bicarbonate form and the biological effluent is  treated  by  the
resin  to  remove  the  inorganic  salts.   After   this step, the
process includes a flocculation/aeration and  precipitation  step
to  remove organic matter; however, this should be  unnecessary if
a sand filter or comparable system is used upstream  of  the  ion
exchange system.  The effluent from the first ion exchange column
is  further  treated  by  a weak cation resin to reduce the final
dissolved salt content to approximately 5 mg/1.  The anion  resin
in  this  process  is  regenerated  with aqueous ammonia, and the


                               129

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u>
o
                               Partial
                              Tertiary
                             Treatment
                              Effluent
Backwash
 Regenerant
   System
                                                                             Tertiary
                                                                             Treated
                                                                             Effluent
                                                Figure 19.   Ion Exchange

-------
cation resin with an aqueous sulfuric acid.   The resins  did  not
appear  to be susceptible for fouling by the organic constituents
of the biological effluent used in this experiment.

Other types of resins are  available  for  ammonia,   nitrate,   or
phosphate  removal  as  well  as  for  color bodies, COD and fine
suspended matter.54 Removal of  these  various  constituents  can
range   from   75   percent  to  97  percent,  depending  on  the
constituent.2 *

The cycle time on the ion exchange unit will be a function of the
time required to block or to  take  up  the  ion  exchange  sites
available  in the resin contained in the system.  Blockage occurs
when  the  resin  is  fouled  by  suspended  matter   and   other
contaminants.   The ion exchange system is ideally located at the
end of the waste water processing scheme, thus having the highest
quality effluent available as a feedwater.

To achieve a recyclable water quality, it  may  be  assumed  that
less  than  500  mg/1  of total dissolved solids would have to be
achieved.  Of the total dissolved solids, 300 mg/1  of  salt  are
assumed  to  be  acceptable.   To  achieve  this  final  effluent
quality, some portion or all of the waste water stream  would  be
subjected to ion exchange treatment.

The  residual  pollution will be that resulting from regeneration
of the  ion  exchange  bed.   The  resin  systems,  as  indicated
earlier,  can  be  tailored to specific ion removal and efficient
use of regeneration chemicals, thus minimizing liquid wastes from
the regeneration step.

Development Status

Ion exchange as a unit operation is well established and commonly
used in a wide range of applications in water treatment and water
deionization.  Water softening  for  boiler  feed  treatment  and
domestic  and  commercial use is probably the most widespread use
of ion exchange in water treatment.  Deionization of water by ion
exchange is used to remove carbon dioxide; metal  salts  such  as
chlorides,   sulfates,  nitrates,  and  phosphates;  silica;  and
alkalinity.  Specific resin applications such as in  waste  water
treatment  have not been widespread up to the present time, since
there has not  been  a  need  for  such  a  level  of  treatment-
However,  processing development and experimental work have shown
the capability of ion  exchange  systems  to  achieve  the  water
quality that may be required for irrigation and closed-loop water
recycle systems.

Part  of  the  economic  success  of  an  ion  exchange system in
treating poultry processing plant waste will probably depend on a
high-quality effluent being available as a feed  material.   This
again,  can  be  provided by an upstream treatment system such as
sand  filtration  to  remove  a  maximum  of   the   particularly
bothersome  suspended organic material.  However, the effect of a
low-quality feed would be primarily economical because of shorter


                               131

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cycle tiineii, rather than a reduction in the overall effectiveness
of the ion exchange system in removing a specific  ionic  species
such as salt.
Problems and Reliability

The application of the technology in waste treatment has not been
tested  and therefore the reliability in that application has yet
to be established.  The problems  associated  with  ion  exchange
operations  would  primarily center on the quality of the feed to
the ion exchange system and its effect on the  cycle  time.   The
operation  and control of the deionization-regeneration cycle can
be  totally  automated,  which  would  seem  to  be  the  desired
approach.   Regeneration solution is used periodically to restore
the ion exchange resin to its original State for  continued  use.
This  solution must be disposed of following its use and that may
require special handling  or  treatment.   The  relatively  small
quantity  of  regenerant  solution  will  facilitate  its  proper
disposal by users of this system.
                               132

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                          SECTION VIII

           COST, ENERGY,  AND NONWATER QUALITY ASPECTS


                             SUMMARY

The waste water from poultry dressing and  processing  plants  is
amenable  to treatment in biological and advanced waste treatment
systems  to  achieve  low  levels  of  pollutants  in  the  final
effluent.   In-plant controls, byproduct recovery operations, and
strict water management practices  can  be  highly  effective  in
reducing  the  waste  load  and waste water flow from any poultry
plant.  Water management practices will reduce the requisite size
of biological and advanced treatment systems  and  improve  their
waste reduction effectiveness.

For   purposes   of   estimating   waste   treatment  costs,  the
subcategories of the poultry processing industry are divided into
groups based on size wherever the data indicated such a  division
as  appropriate.   The plant size division is based on the number
of birds killed within each subcategory, except for  plants  that
further  process  only,  which  are grouped by output of finished
product.  This division of the industry  subcategories  does  not
imply   the   need   to   categorize   according   to  size:  the
categorization rationale  does  not  support  such  a  basis  for
categorizing  the  industry.   Total  investment  costs  and unit
operating costs for waste treatment, on the other hand, will vary
with plant size.  Costs that represent each subcategory situation
could not always be determined on  the  basis  of  one  "typical"
plant  size,  given  the wide range of production and waste water
flow within most of the subcategories.  All costs are reported in
1973 dollars.

Waste water treatment investment cost is primarily a function  of
waste  water  flow  rate.   Cost per unit of production for waste
treatment will vary with total investment cost and the production
rate.  Therefore,  the  subcategory  treatment  costs  have  been
estimated  on  the  basis  of  "typical" plants for each size.  A
"typical"  plant  is  a  hypothetical  plant  with   an   average
production  rate and with a waste water flow rate as indicated by
the data in Table 15.   The  average  raw  waste  load  for  each
subcategory is reported in Sections IV and V of this report.  The
raw  waste  load per unit LWK or FP does not vary with plant size
within each subcategory.

A capital  investment  will  be  required  of  most  plants  with
treatment  systems to upgrade or install waste water treatment to
achieve the waste water quality  specified  for  1977  and  1983.
This additional investment required of a "typical" plant for each
size  in  a  subcategory  to  meet  the  proposed  limitations is
presented in Table  16.   The  capital  costs  will  have  to  be
incurred both for the 1977 and the 1983 limitations, as indicated
in Table 16.
                              133

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                             Table 15.  Typical Plant Operating Parameters Used for Estimating
                                        Cost of Meeting Effluent Limitations
Plant Type
Chicken
Small
Medium
Large
Turkey
Fowl
Small
Large
Duck
Small
Large
Further Processing Only
Small
Large
Production
Birds/Day

51,000
95,000
207,000
12,000

26,400
65,000

3,000
12,000
kg (Ib) FP/Day
21,000 (47,000)
77,000 (170,000)
Waste Water Volume
MM liters/day

1.794
3.38
7.80
1.30

0.964
2.37

0.272
1.10

0.265
0.965
MGD

0.474
0.893
2.05
0.342

0.255
0.627

0.072
0.288

0.070
0.255
U)
JS

-------
u>
                             Table 16-  Additional Investment Cost for "Typical" Plants in Each
                                        Subcategory to Implement Each Indicated Level of
                                        Treatment, No Previous Expenditure Included
!
Plant Type
Chicken
Small
Medium
Large
Turkey
Fowl
Small
Large
Duck
Small
Large
Further Processing Only
Small
Large
Total Industry Cost
•
1977
Limitations

$ 137,000
172,000
244,000
126,000

119,000
154,000

89,000
124,000

88,000
119,000
$13,874,000

1983
Limitations

$ 428,000
542,000
892,000
366,000

346,000
458,000

259,000
354,000

256,000
346,000
$38,642,000
- _---.„.. _^ • 	 	 • - - - - - ••
New Source
Standards

$470,000
640,000
950,000
400,000

364,000
539,000

227,000
385,000

225,000
364,000
—

Irrigation

$183,000
323,000
687,000
138,000

105,000
235,000

35,000
118,000

34,000
105,000
—


-------
The  estimated investment cost to achieve the 1977 limitations is
based on an analysis of the  treatment  systems  in  use  in  the
poultry process industry and their effectiveness on poultry plant
waste  water.  The costs for a "typical" plant to implement waste
treatment to achieve  the  1977  limitations  are  based  on  the
following:

     o  Add an anaerobic lagoon or the equivalent, or expend the
        same dollars on revisions of present treatment systems
        by adding lagoon capacity, mechanical aeration, final
        clarifier or similar option.

     o  install chlorination for the final effluent.

The  following  provide the basis for estimating the cost for the
"typical" plant to  implement  waste  treatment  to  achieve  the
proposed 1983 waste water limitations:

     o  50 percent of the plants with waste treatment will have to
        add dry offal handling systems.

     o  50 percent of the plants will have to install improved
        primary treatment such as dissolved air flotation.

     o  Install a microscreen or sand filter or equivalent, as a
        advanced treatment.

     o  install a nitrification system or ammonia
        stripping equipment or the equivalent, as a advanced
        treatment.

The cost of the irrigation option is presented to demonstrate the
economic  attraction of a waste treatment system that produces no
discharge.  Irrigation by the small  plant  may  be  particularly
attractive from an economic viewpoint.

The  cost  for  new point sources of waste water includes a basic
treatment system such as an anaerobic,  aerated,  aerobic  lagoon
system  plus dissolved air flotation.  The costs are based on the
average waste water flow for each type of plant.

The total cost to the industry is estimated at $13.9 million  for
the  1977 limitations and $38.6 million for 1983.  These are cost
estimates that include the 50-percent factor based on the need of
only half of the plants with waste treatment to add a  dry  offal
handling  system, and 50 percent to make significant improvements
in primary treatment facilities.

The investment in additional waste treatment facilities  involves
the  26 percent of the industry with onsite treatment, less those
plants that already meet the limitations.   The  investment  cost
per  total number of birds killed per year varies from 0.5£ to 60
for 1977 and 1.70 to 180 for 1983 among the various plants in the
industry.  This does not include the  small-size  duck  processor
whose  costs  for  treating  feedlot wastes will probably greatly


                                136

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exceed the treatment costs for the duck  processing  plant  waste
water.   The plants that further process only will have a capital
investment per annual unit of production  of  0.30/kg  (0.750/lb)
for 1977 and l(*/kg (2.2«Vlb)  to meet 1983 limitations.

The  additions  to plant operating cost and total annual cost for
plants to achieve the indicated level of treatment are listed  in
total  dollars  and  per  unit of production in Tables 17 and 18.
The wide range in addition to unit costs is  the  result  of  the
small  duck  plant.  It should also be noted that the unit annual
costs amount to between two and three times  the  unit  operating
costs  because  of  the  high  investment  cost  of the treatment
systems and the method of computing annual cost, using  both  10-
percent depreciation and 10-percent cost of capital as add-ons.

Generally  speaking,  neither  the  capital  requirements nor the
additions to the operating  and  total  annual  costs  appear  to
exceed  the  capabilities  of plants in the industry to raise the
capital or to compete effectively and profitably and  to  earn  a
satisfactory  return,   capital  expenditures by the industry are
reported to have been about $60 million per year for 1970,  1971,
and 1972.3*  Waste treatment will require a higher share of these
expenditures as the limitations are implemented.

The  total  energy  consumption  in  waste water treatment by the
poultry  processing  industry  is  of   little   consequence   in
comparison  to  the  present  total  power consumption of gas and
electricity.  The waste treatment power  consumption  to  achieve
1983  limitations amounts to 2.2 percent of the total consumption
of fuel and electricity by poultry plants.  Waste treatment power
consumption amounts to about 12 percent of the  electrical  power
consumption in poultry plants.

With the implementation of the proposed limitations, land becomes
the primary waste sink instead of air and water.  The waste to be
landfilled  can  improve soils with nutrients and soil conditions
contained  in  the  waste.   Odor  problems  can  be  avoided  or
eliminated in all treatment systems.


                         "TYPICAL" PLAN*!

The  waste  treatment  systems applicable to waste water from the
poultry processing industry can be used  by  all  plants  in  the
subcategories  of  the  industry.  A hypothetical "typical" plant
was constructed for each size in each subcategory  as  the  basis
for  estimating  investment  cost  and  total annual cost for the
application of each  waste  treatment  system.   The  costs  were
estimated   and,   in   addition,   effluent   reduction,  energy
requirements, and  nonwater  quality  aspects  of  the  treatment
systems were determined.

The waste treatment systems are applied on the basis of the plant
constructs for each subcategory, as indicated previously in Table
15.

                               137

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                     Table 17. Addition to the Total Annual Cost and Operating* Cost  for a Plant
                               in Each Subcategory to Operate Treatment System as Described
Plant Type
Chicken
Small
Medium
Large
Turkey
Fowl
Small
Large
Duck
Small
Large
Further Processing
Only
Small
Large
1977
Operating

$22,450
26,800
35,200
20,700

19,800
24,600

16,450
20,000

16,400
19,800
Annual

?49,850
61,200
84,000
45,900

43,600
55,400

34,250
44,800

34,000
43,600
1983
Operating

$ 70,650
95,100
161,400
60,900

56,000
79,300

41,860
111,460

41,550
55,900
Annual

$183,650
237,900
388,600
159,300

149,000
201,700

57,600
153,200

110,350
148,900
New Source
Operating

$54,000
67,100
90,400
48,300

45,400
59,700

35,300
46,400

35,100
45,400
Annual

?148,000
195,100
280,400
128,300

118,200
167,500

80,700
123,400

80,100
118,200
Irrigation
Operating

$29,800
35,000
46,000
27,700

26,250
32,000

22,900
26,600

22,900
26,200
Annual

$66,400
99,600
183,400
55,300

47,250
79,000

29,900
50,200

29,700
47,200
CO
         *Total annual cost includes operating cost plus  capital cost and depreciation  in  dollars  per
          Total operating  cost includes manpower and burden,  supplies,  chemicals,  power,  taxes,  and
          insurance in dollars per year.
year,

-------
Table 18.  Additions to the Annual Cost and Operating Cost Per Unit of Production for
           a Plant in Each Subcategory to Operate Treatment System as Described
Plant Type
Chicken, C/bird
Small
Medium
Large
Turkey, 
-------
                     WASTE TREATMENT SYSTEMS

The   waste   treatment   systems  included  in  this  report  as
appropriate for use  on  poultry  processing  plant  waste  water
streams can be used, subject to specific operation constraints or
limitations  as  described later, by most plants in the industry.
The  use  of  some  treatment  systems  may  be  precluded   from
consideration  by technical, physical, or economic impracticality
for some plants.

The waste treatment systems, their uses,  and  typical  range  of
effluent reduction associated with each are listed in Table 19.

The  dissolved  air  flotation system can be used upstream of any
biological treatment system.  The use of chemicals will  increase
the  quantity  of  grease removed from the waste water system, as
indicated in Table 19.

The biological treatment systems  are  generally  land  intensive
because of the long retention time required in natural biological
processes.   Mechanically  assisted systems have reduced the land
requirements, but increased the energy consumption  and  cost  of
equipment  to achieve comparable levels of waste reduction.  Some
of the advanced systems are interchangeable.  They can be used at
the end of any of the biological treatment systems, as  required,
to achieve a specific effluent quality.  Chlorination is included
as a disinfection treatment.

The  most  feasible  system  for poultry processors to achieve no
discharge at this time is flood or spray irrigation.  Closing the
loop to a total water recycle or reuse system may be  technically
feasible,  but  far too costly for consideration.  The irrigation
option does require large plots of accessible  land—roughly  2.0
hectares/million  liters  (18  acres/thousand  gallons)  of waste
water per day—and limited concentrations  of  dissolved  solids.
More  detailed  descriptions  of  each  treatment  system and its
effectiveness are presented in Section VII—Control and Treatment
Technology.

A study conducted by the Economic Research Service  of  the  USDA
reported  the  type  of  waste  water  treatment  employed by 386
poultry  plants.1  The  distribution   between   private   onsite
treatment  and  municipal  treatment  reported in this USDA study
provided the basis for the data presented in Table 20 on industry
waste water treatment practice by  subcategory  and  plant  size.
The  distribution among subcategories and sizes is based on North
Star survey questionnaire data covering about  140  plants.   The
total  number  of 390 plants is based on an average of the number
reported in three different sources and on information  collected
from the industry during this research program.1,2,36

There is a dominant waste treatment pattern among duck processors
who  almost  always  treat  their own waste water; except for one
plant, duck processing plants apparently include a  duck  feedlot


                              140

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  Table 19. Waste Treatment Systems,  Their Use and Effectiveness
 Treatment System
Dissolved air
flotation (DAF)
DAF with pH control
and flocculants
added

Anaerobic + aerobic
lagoons

Anaerobic contact
process

Activated sludge

Extended aeration
Anaerobic lagoons +
rotating biological
contactor

Chlorination


Sand filter


Microstrainer


Ammonia stripping

Chemical
precipitation


Spray irrigation

Flood irrigation

Ponding and
evaporation

Nitrification and
denitrification
         Use
  Effluent Reduction
Primary treatment or
by-product recovery
Primary treatment or
by-product recovery


Secondary treatment


Secondary treatment


Secondary treatment

Secondary treatment

Secondary treatment
Finished and
disinfection
Tertiary treatment &
secondary treatment
Tertiary treatment
Tertiary treatment

Tertiary treatment



No discharge

No discharge

No discharge


Tertiary treatment
Grease, 60% removal,
 to 100 to 200 mg/1
BOD5, 30% removal
SS, 30% removal

Grease, 95-99% removal
BOD5, 90% removal
SS, 98% removal

BOD5, 95% removal
BOD5, 90-95% remova]


BOD5, 90-95% removal

    , 95% removal
    , 90-95% removal
BOD5, to 5-10 mg/1
SS, to 3-8 mg/1

BOD5, to 10-20 mg/1
SS, to 10-15 mg/1

90-95% removal

Phosphorus, 85-95%
 removal, to 0.5 mg/1
 or less

Total

Total

Total
N, 85% removal
                            141

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Table 20.  Industry Breakdown by Subcategory, Size, and Type of Waste Treatment
Plant Type
Chickens
Small
Medium
Large
Turkey
Fowl
Small
Large
Ducks
Small
Large
Further Processing
Only
Small
Large
Total
Total
Number
of
Plants
222
133
82
7
112
26
18
8
10
4
6
20
16
4
390
Private, On-Site
Treatment
Number
of Plants
64
39
23
2
22
5
3
2
9
4
5
2
2
0
102
Percent of
Subcategory
29



20
19


91


10


26.2
Municipal
Treatment
Number
of Plants
153
91
57
5
89
20
14
6
1
0
1
18
14

281
Percent of
Subcategory
69



79
76


9


90


72-. 0
No
Treatment
Number
of Plants
5
3
2
C
1
1
1
0
0


0


7
Percent of
Subcategory
2



1
5


0


0


1.8

-------
and  its  waste  water.   Likewise,  a poultry plant that further
processes only is almost always on municipal treatment.  In fact.
North Star found no further processing only plant with an  onsite
treatment  system.   Among the subcategories other than ducks and
further processing only, between 20 and 30 percent of the  plants
apparently have onsite treatment.  The number of plants indicated
in  Table  20  with no treatment and a waste water discharge to a
stream is  based  on  the  data  in  the  USDA  study  previously
mentioned.

Irrigation of waste water was reported by one plant located in an
arid  region  of  the Western United States and by another in the
East North Central region of the country.   A  microstrainer  was
observed in use as a final treatment device in one plant.  It was
found  to  be  very effective in the removal of suspended solids.
Seventeen plants reported using  dissolved  air  flotation  as  a
primary   treatment.   Chlorination  was  reportedly  used  as  a
finishing treatment by 14 plants among  the  respondents  to  the
survey questionnaire.


                   TREATMENT AND CONTROL COSTS

                     In-Plant Control Costs

The  cost  of  installation  of  in-plant controls is primarily a
function of the specific plant situations.  Building  layout  and
construction  design  will largely dictate what can be done, how,
and at what cost in regard to in-plant waste control  techniques,
The  in-plant  control  costs  included  in  the  investment cost
estimates are for water recirculation to  the  feather   flow-away
system  for  1977  and  dry  offal handling and improved primary
treatment for 1983.
                  Investment Costs Assumptions

The  waste  treatment  system  costs  are  based  on  the   plant
production,  waste  water flow and BODS figures listed previously
for  "typical," but  hypothetical,  plants  in  each  subcategory.
Investment costs for specific waste treatment systems are largely
dependent on the waste water flow or  hydraulic load.  Most of the
lagoon systems are designed on BOD5 loading, which has been shown
to   increase  with  increased  water  use, however, cost estimates
based on flow are adequate for the purposes of this study.

Cost effectiveness data are presented in Figures  20  and  21,  as
the  investment  cost  required  to   achieve  the indicated BOD5
removal with two different waste treatment systems at two  levels
of waste water flow.  The low flow  (Figure 20) is typical for the
average  size  plants in the industry.  The high  flow  (Figure 21)
is more typical of the large plants in  the  industry.   The  raw
waste  reduction  is  based  on  the  construct of idealized waste
treatment systems with the incremental waste  reduction  achieved
by   adding  treatment  components  to the system as indicated in
                               143

-------

p
z
UJ
O
cc
UJ
CTION
Q
UJ
CC
Q
O
UJ
CO
5
g
3
QC
UJ
H
5
X
o
QC
Q.

99.9
99.5

99
98
95
90


80
70
60
50

40
30
20



10

-

---j_ g TmTlflRY TnrATMFMT

*
.
-
-
-


• LAGOON 1
TREATMENT U-
- SYSTEM 1
-
_

-
-
-




"

I 1 ADVANCED SECONDARY
f (TREATMENT
1 ^ [ SECONDARY TREATMENT
| [LEVEL
1
1
1
ACTIVATED SLUDGE
| SYSTEMS
1
1



•— -rmiviMriT incMimci^i LEVEL.





i i i i i i i i i
100 200 300  400  500  600 700  800 900 1000

                  INVESTMENT COST ($1000's)

  Figure 20.   Waste  Treatment  Cost  Effectiveness at Flow
              of 1.14 Million  Liters/Day  (0.300 MGPD)

-------
APPROXIMATE RAW WASTE LOAD REDUCTION (PERCENT)
•-'••- '• . •.:,•-•,< (o  vi oo to co to to J° 5°
D O O OOOOOO O OV 00 CO O1 CO
L
1
s
k
.-• - I',.- 	
AGOON
•REATMENT
YSTEM
.*"


-,_-*J TERTIARY
("TREATMENT
i
J JADVANCED SECONDARY
i - *• ITREATMENT
| ISECONDARY TREATMENT
1 * 1LEVEL
ACTIVATED
SLUDGE &
AERATION
SYSTEMS
PRIMARY TREATMENT
LEVEL
	 1 	 J« 	 ,A 	 ,A.,,. 	 J. 1 —I 	 ^J 	 1 	 1 	 -*-
            INVESTMENT COST ($1000's)
Figure 21.   Waste  Treatment  Cost Effectiveness at Flow
            of 3 Million Liters/Day  (0.800 MGPD)

-------

-------
Table 21.  Waste Treatment System Configurations
           for Cost Effectiveness Curves
Low Cost System
Catch basin
+ Dissolved air
flotation
+ Anaerobic and
aerobic lagoons
+ Aerated lagoon
+ Sand filter
High Cost System
Catch basin
+ Dissolved air
flotation
+ Activated sludge
+ Extended aeration
+ Sand filter
Total Raw
Wast e-- Reduet ion:-
BOD5 (%)
0
30
95
98
99+

-------
 for  new  ventures.   The  ten   percent   figure   is   probably
 conservative  and  thus tends to contribute to a high estimate of
 total annual cost,  operating cost includes all the components of
 total annual cost except capital cost and depreciation,  wherever
 it is reported.

 The  depreciation  component  of  annual  cost was estimated on a
 straight-line basis, with no salvage value and  a  ten-year  life
 for  all  investment  costs,  except  land  cost  which  was  not
 depreciated.

 The operating and maintenance costs for the 1983 systems  include
 the  cost  of  one man-year at $4.20 per hour plus 50 percent for
 burden, supervision, etc.  A licensed  waste  treatment  operator
 would  add  another $5,000 to operating costs per year.  One-half
 man-year was used for the annual cost for  the  1977  limitations
 plus   the  50-percent  burden,  etc.   General  and  maintenance
 supplies, taxes, insurance,  and  miscellaneous  operating  costs
 were  estimated  at five percent of the total investment cost per
 year.  Specific chemical-use costs were added when such materials
 were consumed in the waste treatment system.  By-product  income,
 relative  to waste treatment, was credited only in the irrigation
 system for 13,400 kg (29,480 lb)of dry matter (hay or grass)  per
 hectare, at $22 per 100 kg of hay, with two crops per year.  This
 is  equivalent  to a yield of six tons per acre valued at $20 per
 ton of dry hay.

 Costs per unit of production were based on 250 operating days per
 year at the average daily  production  rate  for  plants  in  the
 chicken, fowl, and further processing only subcategories.  Turkey
 and  duck  processors were assumed to slaughter only 170 days, or
 about 2/3 of the year,  and at the average  daily  production  for
 each subcategory.


                       ENERGY REQUIREMENTS

 The  electrical  energy  consumption  by  the  poultry processing
 industry was reported for 1971 at 1.2 million KWH and total  heat
 and   power   consumption  at  6.4  million  KWH.e   The  poultry
 processing  industry  consumes  relatively  small  quantities  of
 electrical  energy,  but large quantities of fuel for cooking and
 heating.  The waste treatment systems require power primarily for
 pumping and aeration.  The aeration horsepower is a  function  of
 the  waste load, and that for pumping depends on waste water flow
 rate.

Total power consumption for current waste treatment,  which  will
 be  essentially the same for 1977 limitations, is estimated to be
 about  50  million  KWH  per  year  for  the  poultry  processing
 industry.   This  amounts  to about 4.2 percent of the industry's
 electrical energy consumption and less than 1.0 percent of  total
 energy  consumption  reported  for  1971.   An  additional  power
 consumption increment of 50 to 60 million KWH is estimated to  be
 required  to  achieve  1983  limitations.   Again, using the 1971


                              148

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consumption levels as a baseline,  this amounts to 8.5 percent  of
electrical  energy and 2.2 percent of total energy.   This nominal
increase does not appear to raise  serious power  supply  or  cost
questions  for  the  industry.   However,  the  widespread use of
chlorine as a disinfectant may pose some energy problems  in  the
future,  or,  conversely,  the  future  supply of chlorine may be
seriously affected by the developing energy  situation  in  which
event alternative disinfection procedures may be required.

Waste  treatment  systems  impose  no significant addition to the
thermal energy requirements of plants.  Waste water can be reused
in various services in poultry processing plants.   Heated  waste
waters  improve  the  effectiveness of anaerobic ponds, which are
best maintained at 32°C  (90°F) or higher.  Improved water use and
thermal efficiencies are possible within a plant when waste water
reuse is maximized.

Waste water treatment costs and effectiveness can be improved  by
the use of energy and power conservation practices and techniques
in  the  processing plant.  The waste load tends to increase with
increased water use.  Reduced water  use  therefore  reduces  the
waste  load,  pumping costs, and heating costs, the last of which
can be further reduced by Water reuse, as suggested previously.


          NONWATER POLLUTION BY WASTE TREATMENT SYSTEMS

                          Solid Wastes

Solid  wastes  are  the  most  significant  nonwater   pollutants
associated  with  the  waste  treatment systems applicable to the
poultry processing industry.  Screening devices of various design
and operating principles are used primarily for removal of  large
solids  from  waste  water.   These solids may have some economic
value as inedible rendering material, or they may  be  landfilled
or spread with other solid wastes.

The  solids materials separated from the waste water stream which
contain organic and inorganic matter, and the chemicals added  to
aid  solids  separation  are  called  sludge.   Typically, sludge
contains 95 - to 98-percent water before  dewatering  or  drying.
Both  primary  and  biological  treatment  systems  generate some
quantity of sludge; the quantity will vary by the type of  system
and is roughly estimated in Table 22.
                              149

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Ui
o
                                           Table 22.   Sludge Volume Generation
                                                      by Waste Treatment Systems
                                   Treatment  System
Dissolved air flotation

Anaerobic lagoon

Aerobic and aerated lagoons

Activated sludge

Extended aeration

Anaerobic contact process

Rotating biological contactor
                                   Sludge Volume as Percent of Raw
                                         Waste Water Volume
Up to 10%

Sludge accumulation in these
lagoons is usually not sufficient
to require removal at any time.

10 to 15%

5 to 10%

Approximately 2%

Unknown

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The  raw  sludge can be concentrated, digested,  dewatered,  dried,
incinerated, landfilled on site,  or  spread  in  sludge  holding
ponds.    The sludge from any of the treatment systems,  except air
flotation with polyelectrolyte chemicals added,   is  amenable  to
any of  these sludge handling processes.

The  sludge  from  air flotation with chemicals addition has been
found to be difficult to  dewater,   A  dewatered  sludge  is  an
acceptable  landfill  material.  Sludge from biological treatment
systems is normally ponded by industry plants on their  own  land
or  dewatered or digested sufficiently for hauling and deposition
in public landfills.  The final  dried  sludge  material  can  be
safely  used  as an effective soil builder.  Prevention of runoff
is a critical factor in plant-site sludge holding  ponds.   Costs
of   typical  sludge  handling  techniques  for  each  biological
treatment system generating sufficient quantities  of  sludge  to
require  handling  equipment  are included in the costs for these
treatment systems.

For those waste materials considered to  be  non-hazardous  where
land  disposal  is  the choice for disposal, practices similar to
proper  sanitary  landfill  technology  may  be  followed.    The
principles  set  forth in the EPA1 s Land Disposal of Solid Wastes
Guidelines  (CFR Title 40, Chapter 1; Part 2U1)  may  be  used  as
guidance for acceptable land disposal techniques.

For  those  waste  materials considered to be hazardous, disposal
will require special precautions.  In order to  insure  long-term
protection   of   public  health  and  the  environment,  special
preparation and pretreatment may be required prior  to  disposal.
If  land  disposal is to be practiced, these sites must not allow
movement of pollutants such as fluoride and radium-226 to  either
ground  or  surface  water.   Sites  should be selected that have
natural  soil  and  geological   conditions   to   prevent   such
contamination  or,  if  such  conditions do not exist, artificial
means   (e.g.,  liners)  must  be  provided  to  insure  long-term
protection  of  the  environment from hazardous materials.  Where
appropriate, the location of solid hazardous  materials  disposal
sites should be permanently recorded in the appropriate office of
the legal jurisdiction in which the site is located.

                          Air Pollution

Odors  are  the only significant air pollution problem associated
with  waste  treatment  in  the  poultry   processing   industry.
Malodorous  conditions usually  occur in anaerobic waste treatment
processes ,or  localized  anaerobic  environments  within  aerobic
systems.   However,  it  is generally agreed that anaerobic ponds
will not create serious odor problems unless  the  p ocess  water
has a sulfate content; then they most assuredly wil?.
 j
Sulfate waters are definitely a localized condition, varying even
from well to well within a specific plant.  In northern climates,
the  change  in  weather  in  the  spring may be accompanied by a
period of noticeable odors.  In some cases, a cover or  collector
                               151

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of the off-gas from the pond is an effective odor control device.
The off-qas is burned in a flare.

Odors have been generated by some air flotation systems which are
sometimes housed in a building, thus localizing, but intensifying
the  problem.  Minimizing the unnecessary holdup of any skimmings
or grease-containing solids has been suggested as a remedy.

Odors can best be controlled by elimination at the source, rather
than resorting to  treatment  for  odor  control,  which  remains
largely unproven at this time.


                              Noise

The  only  material  increase  in noise within a processing plant
caused by waste treatment is that caused by the  installation  of
an  air  flotation  system  or  aerated lagoons with air blowers.
Large pumps and an air compressor are part of  an  air  flotation
system.  When such a system is housed in a low-cost building, the
noise generated by an air flotation system is confined within the
building,  but  the  noise may be amplified to high levels in the
building by such installation practices.   All  air  compressors,
air  blowers,  and  large  pumps  in  use  on intensively aerated
treatment systems, and  other  treatment  systems  as  well,  may
produce  noise  levels  in  excess of the Occupational Safety and
Health Administration limitations.  The  industry  must  consider
these limitations in solving its waste problems.
                              152

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                           SECTION IX

    EFFLUENT REDUCTION ATTAINABLE THROUGH THE APPLICATION OF
             THE BEST PRACTICABLE CONTROL TECHNOLOGY
      CURRENTLY AVAILABLE—EFFLUENT LIMITATIONS GUIDELINES
                          INTRODUCTION

The  Agency/  in  establishing effluent limitations which must be
achieved by July 1, 1977, is to specify the  degree  of  effluent
reduction   attainable   through  the  application  of  the  Best
Practicable  Control  Technology   Currently   Available.    This
technology  is  generally  based  upon  the  average  of the best
existing performance by plants of various sizes, ages,  and  unit
processes  within  the  industrial  category  and/or subcategory.
This average was not based upon a broad range  of  plants  within
the  poultry  processing  industry,  but  based  upon performance
levels achieved by exemplary plants.

Consideration was also given to:

     o  The total cost of application of technology in relation to
        the effluent reduction benefits to be achieved from such
        application;

     o  The size and age of equipment and facilities involved;

     o  The processes employed;

     o  The engineering aspects of the application of various types
        of control techniques;

     o  Process changes;


     o  Nonwater quality environmental impact (including energy
        requirements) .

While Best Practicable  Control  Technology  Currently  Available
emphasizes  treatment  facilities  at  the end of a manufacturing
process, it includes waste  water  control  measures  within  the
process  itself which are considered to be normal practice within
an industry.

A further consideration is the degree of economic and engineering
reliability which must be established for the  technology  to  be
"currently  available,"   As  a result of demonstration projects,
pilot plants, and general use, there must exist a h:jh degree  of
confidence  in the engineering and economic practic bility of the
technology at the time of start of construction  of  the  control
facilities.
                               153

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    EFFLUENT REDUCTION ATTAINABLE THROUGH THE APPLICATION OF
     BEST PRACTICABLE CONTROL TECHNOLOGY CURRENTLY AVAILABLE

Based  on  the information contained in Sections III through VIII
of this report, a determination has been made that the quality of
effluent  attainable  through  the  application   of   the   Best
Practicable  Control  Technology Currently Available is as listed
in Table 23,  In the industry study summarized herein, ten of the
plants  in  the  chicken  category,  two  plants  in  the  turkey
category,  and one plant in the duck processing category meet the
proposed BOD5 limitations.  All plants in the sample representing
the fowl and further processing only subcategories were found  to
discharge  to  municipal  treatment systems.  Therefore, no final
effluent data were available in these subcategories.

Plants with onsite rendering or further processing (not including
cut-up only operations), in  addition  to  slaughtering,  require
adjustments  in  the  BOD5,  TSS,  and  Grease  limitations.   An
adjustment in effluent limitations is  also  warranted  for  duck
processing  plants  that  have an adjunct feedlot operation.  The
adjustments for further processing are  the  values  for  further
processing  only  given  in  Table 23; the adjustments for onsite
rendering are the values developed for the independent  rendering
industry.39  These  adjustment factors are presented in Table 24,
Adjustments for further processing are  permitted  only  for  the
production  from  further  processing  that  includes cooking and
processing activity  encompassed  as  part  of  cooking  such  as
breading,  spicing,  canning,  etc.   This  excludes  cut-up only
operations.  The reason for this is that the raw waste loads  for
plants  with  only  slaughtering operations are not distinctively
different from plants with slaughter plus cut-up operations  (see
Section IV) .

It  appears  that  the  circumstances  of several duck processors
associated with feedlots are somewhat different  than  processors
operating  alone.   As a result, it is apparent that any effluent
restrictions should be so derived  as  to  properly  account  for
waste load contributions from both the feedlot and the processor.
While  the small number of operations affected does not appear to
warrant a specific separate regulation or new subcategory  ,  the
Agency  has concluded that the effluent limitation for a combined
feedlot/processor should  be  developed  on  an  additive  basis.
Thus,  in  the  event  that  waste  streams  from the feedlot and
processor are combined for treatment or discharge,  the  quantity
of  each  pollutant  or  pollutant  property  controlled for each
separate component or waste source shall not exceed the specified
limitation for that waste source.  For  parameters  regulated  by
only  one of the potentially applicable regulations, the ultimate
limitation should be derived on a flow-proportioned  basis.   For
example, the pollutant "total suspended solids" is not controlled
by  an  effluent limit for a duck feedlot, but is specified for a
duck processor.  In this instance,  the  portion   (determined  by
respective  flow  volume) of suspended solids attributable to the
processor in the combined effluent must not exceed the limitation
specified for a duck processor in Table 23,


                             154

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                              Table 23.  Recommended Effluent Limitations  for July  1,  1977
Industry
Subcategory
Chickens
Turkeys
Fowl
Ducks
Further Processing
Only
Effluent Parameters
B0%,_. kg/kkg LWK*
0.46
0.39
0.61
0.77
0.30 kg/kkg FP
SS, kg/kkg LWK '
0.62
0.57
0.72
0.90
0.35 kg/kkg FP
Grease, kg/kkg LWK
0.20
0.14
0.15
0.26
0.10 kg/kkg FP
Fecal Coliform,
Max. Count/100 ml
.
400
400
400
400
400
Ln
Ui
           *kg/kkg LWK is equivalent to lb/1000 Ib LWK

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plants as well.  The further processing adjustment factors become
significant  when  a  plant further processes the majority of its
kill,


           IDENTIFICATION OF BEST PRACTICABLE CONTROL
                 TECHNOLOGY CURRENTLY..AVAILABLE

Best Practicable Control Technology Currently Available  for  the
poultry  processing  industry involves biological waste treatment
following  in-plant  primary  treatment  for  grease  and  solids
recovery.   By  definition, in-plant byproduct recovery of blood,
feathers,  and  offal  is  not  considered  as  in-plant  primary
treatment.   To  assure that the biological treatment system will
successfully achieve the limits specified, plant operators should
consider reduction of the raw waste load entering  the  treatment
system by employing one or more of the following housekeeping and
management measures, all of which are currently practiced at some
plants in the industry:

     o  Appoint a person with specific responsibility for water
        management.  This person should have reasonable powers to
        enforce improvements in water and waste management,

     o  Determine or estimate water use and waste load strength from
        principal sources.  Install and monitor flowmeters in all
        major water use areas,

     o  Control and minimize flow of freshwater at major outlets
        by installing properly sized spray nozzles and by regulating
        pressure on supply lines,

     o  Shut off all unnecessary water flow during work breaks.


     o  In-plant primary systems—catch basins, skimming tanks, air
        flotation, etc.—should provide for at least a 30-minute
        detention time of the waste water.

     o  Avoid overfilling cookers in rendering operation.

     o  Provide and maintain traps in the cooking vapor lines of
        rendering operations to prevent overflow to the condensers.
        This is particularly important when the cookers are used to
        hydrolyze feathers,

     o  Provide frequent and regularly scheduled maintenance attention
        for byproduct screening and handling systems throughout the
        operating day.

     o  Dry clean all floors and tables prior to washdown  to reduce
        the waste load.  This is particularly important in the
        bleeding, cutting, and further processing areas and all
        other  areas where materials tend  to be spilled.


                              158

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     o  Use high-pressure,  low-volume spray nozzles or steam augmented
        systems for plant washdown.

     o  Control inventories of raw materials used in further processing
        so that none of these materials are wasted to the sewer.
        Spent raw materials should be routed to rendering.

     o  Make all employees aware of good water management practices
        and encourage them to apply these practices.

The above practices can readily help in waste control by reducing
raw  waste loads.  Other actions such as minimizing the amount of
chemicals and detergents used, keeping at USDA-approved water use
rates in scalders and chillers, installing "demand" valves on all
freshwater outlets, or practicing dry offal  handling  are  other
potentially   useful   waste   control  options  which  need  not
necessarily be instituted.  Available information indicates  that
a  number  of plants are practicing the principles encompassed in
the above  waste  control  activities.   Even  if  these  control
activities  are  not  fully  implemented, well-operated treatment
processes currently used by the industry and  listed  below  will
permit the recommended limits to be achieved.

     1.  Anaerobic lagoon + aerobic  {shallow)  lagoons;

     2.  Activated sludge  (or extended aeration) + aerobic  (shallow)
         lagoons;

     3,  Aerated lagoons + aerobic  (shallow) lagoons;

     U.  Anaerobic + aerated + aerobic  (shallow) lagoons.

Plants  with  higher-than-average  raw  waste loads or undersized
treatment systems may require an additional solids removal  stage
(e.g.,  clarifier).  Chlorination usually will be required as the
final treatment process.


         RATIONALE FOR THE SELECTION OF BEST PRACTICABLE
             CONTROL TECHNOLOGY CURRENTLY AVAILABLE

The  rationale  used  in  developing  the  effluent   limitations
presented  in  Table 23 was based upon actual performance data  of
plants having complete biological waste  treatment  or  upon  raw
waste characteristics and transfer of waste treatment technology.
A complete biological treatment system would include any properly
sized system mentioned in the preceding subsection.
                              159

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                 SIgS, AGE, PROCESSES EMPLOYED,
                     LOCATION OF FACILITIES

The  processes  employed  in small and large poultry slaughtering
plants and  further  processing  plants  are  basically  similar.
Furthermore, the factors of size, age, and processes employed did
not  appear  to  affect  the  pollution  control techniques used.
Hence these factors were not directly  employed  in  establishing
effluent limitations.  Also, the location of facilities was not a
major  factor,  although  it  may contribute slightly to seasonal
variations in waste load and final effluent.

            TOTAL COST OF APPLICATION IN RELATION TO
                   EFFLUENT REDUCTION BENEFITS

Based on information contained in Section VIII  of  this  report,
the  total  investment  cost to the poultry industry to implement
the waste treatment to achieve the 1977 effluent  limitations  is
estimated  to  be  $13.9  million.  This amounts to 23 percent of
total capital expenditures of $60 million by the industry in each
of the three years 1970, 1971, and 1972.

Moreover,  this  level  of  expenditure  is  associated  with   a
substantial   reduction   in  pollution  discharged  directly  to
navigable waters.  Using BOD5 as a basis for calculations, it  is
estimated  that  the  poultry  processors   (with  a direct stream
discharge)  are discharging about 13 million  pounds  of  BODJ5  to
streams  each  year at present levels of pollution control.  Full
implementation of the effluent  limitations  for  BOD5  by  these
plants is estimated to provide a reduction of 75 percent in BOD5.,
to  a level of about 3.5 million pounds per year.  The investment
cost versus pollution  load  reduction  relationship  amounts  to
about  $1.50 per pound of BOD5 removed for the time period during
which the 1977 limitations are applicable.

The additional operating  cost  associated  with  achieving  1977
limitations  for chicken, turkey, and fowl processors varies from
0.072/bird to l*/bird, and for duck processors from 1.0*/bird  to
3.22/bird.     Plants   that   further  process  only  will  incur
additional operating costs from  0.1*  to  0.3*/kg  FP  (0.05  to
0.14£/lb  FP).   The  total  annual  cost  increase  per  unit of
production to achieve 1977 limitations varies  from  2.2  to  2.4
times  the  operating  cost  increase.   The  large plants in the
industry will experience the lower  cost  increase  per  unit  of
production.
                        DATA PRESENTATION

Table  25  presents  the data for 13 exemplary chicken processing
plants.  Included in Table 25 are the plant  size   (thousands  of
birds  per  day);  effluent  flow;  raw  and final waste  loads  for
BOD5, TSS, and grease; fecal coliform counts in the final treated
                             160

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                                 Table  25.   Waste Treatment Data For  Exemplary
                                              Chicken,  Turkey, and Duck Plants
Plant
Number
Chickens
1
2
3
4

5tt

6

7
8
9
10
11
12
Turkeys
13
14
15
16
17
Ducks
18
19
Flow
liters/bird
(gal/bird)

29.1 (7.7)
24.2 (6.4)
30.3 (8.0)
37.8 (10.0)

51.5 (13.6)

40.9 (10.8)

23.5 (6.2)
23.8 (6.3)
15.5 (4.1)
33.3 <8.8)
17.4 (4.6)
35.6 (9.4)
	
113.9 (30.1)
61.3 (16..2)
170.3 (45)
135.1 (35.7)
132.5 (35)

71.5 (18.9)
78.3 (20.7)
Production
1000 birds/day

65
55
36
65

70

140

45
84
22
BOD5,
kg/kkg LWK*
Raw

7.12
6.98
5.88
—

10.54

13.00

6.30
4.32
6.29
200 13.48
60
85

9.4
21-
4.4.6
4.36
Final

0.47
0.39
0.66
0.26

0.24

0.51

0.50
0.39
0.45
0.64
0.40
0.32
;
4.69! 1-25
2.70 0.18
6 ! 3.22 0.59
4.2
20
0.96 0.49
0.41
i
10 j 7.52 0.54
15 6.59 1.32
ss,
kg/kkg LWK*
Raw

6.06
5.00
5.77
—

5.01

5.11

10.30
2.38
5.32
5.47
3.97
3.51

3.55
1.52
2.41
0.99
—

3.47
5.24
Final

0.14
0.44
0.23
0.52

0.19

0.12

1.40
0.43
0.59
0.46
0.50
0.22

0.62
0.57
1.18
0.50
0.63

0.81
1.61
Grease,
kg/kkg LWK*
Raw

—
5.39
1.67
—

4.03

2.91

6.10
—
—
—
—
—

1.46
0.44
0.88
0.35
—

3.05
0.66
Final

—
0.45
0.19
—

0.34

0.14

0.20
—
—
—
—
—

0.025
0.13
0.067
0.076
—

0.13
0.073
Final Fecal
Coliforms**,

Counts/100 ml Waste Treatment System

1100
—
—
<100(CL)

<100(CL)

3300(CL)

~
—
<100
—
—
—
anaerobic, 3 aerobic
2 aerated, 2 aerobict
2 anaerobic, aerobic
3 anaerobic, aerated,
aerobic
activated sludge,
micro strainert
anaerobic , aerated ,
aerobic
aerated
extended aeration, aero.b-.ict
aerated, 2 aerobic
3 aerated, 2 aerobict
anaerobic , aerated , aerobict
extended aeration, aerobic

100 activated sludge, aerobic
3 aerated
<100(CL) aerated, 2 aerobict
1700 anaerobic, aerobic
aerated , aerobic

<100(CL) activated sludge, aerobic
<100(CL) 3 aerated, 2 aerobic
 *kg/kkg LWK. = lb/1000 Ib LWK.
**(CL) indicates  chlorliration of-final effluen.t.
 tindicates air flotation primary treatment.
!tThe performance of the treatment system  for Plant  5
was used to establish 1983 effluent limitations.

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effluent; and the type  of  biological  waste  treatment  systems
used.

Table  25 also includes the same information tor exemplary turkey
and duck processing plants.  Similar data for fowl processing and
for further processing only plants are not available because  all
of  these  plants  that  responded to the questionnaire indicated
discharged their raw waste water to municipal treatment systems.


Chickens

Data  for  three  of  the  chicken  processing  plants  represent
information obtained from our field sampling survey; data for two
plants  were  provided  directly  by  the companies; and data for
eight plants were obtained from questionnaire information.

The BOD5 effluent limitation of 0.46 kg/kkg LWK is the average of
all final BOD5 values except for  Plant  No.  5  presented  under
chickens  in ~*Table  25.   The value for Plant No. 5 was excluded
because  its  waste  treatment  system  includes  advanced  waste
treatment.   Seven  of  the twelve plants listed in Table 25 meet
this effluent limitation; eight of thirty-two  plants  for  which
final data were available meet the limitation.  Using the average
of  all  flow  values  (excluding Plant No. 5) of 28.3 liters (7.5
gal)/birdr and an average bird weight of 1.74 kg  (3.8  Ib) ,  the
corresponding final BOD5 effluent concentration is 28 mg/1.   This
concentration  is  considered  to  be  attainable  using the best
practicable control technology currently available.

The suspended solids (TSS) effluent limitation of 0.62 kg TSS/kkg
LWK is the average of the values listed in Table 25 for Plants 2,
4, 7, 8, 9, 10, and 11.  The  TSS  value  for  Plant  5  was  not
included  because this plant had advanced waste treatment; values
for Plants 1, 3, and 6 were excluded because  these  values  were
unusually  low relative to the corresponding BOD5 values for each
plant.  A regression equation was developed from an  analysis  of
treated  effluent  values  for BOD5 and TSS from 30 plants.   This
equation predicts, with a high correlation, that  the  final  TSS
value  should be greater than the final BODS^ value.  In addition,
this regression equation predicts a TSS  value  of  0.65  kg/kkg,
using  the  BOD^  effluent  limitation  value of 0.46 kg/kkg LWK.
This predicted value for TSS agrees  well  with  the  recommended
effluent  limitation value.  Again using the flow value of 28.3 1
(7.5 gal) per bird and an average bird weight  of  1.74  kg  (3.8
Ib) ,   this   effluent   limitation   value   corresponds   to  a
concentration of 38 mg/1.  Eleven of the twelve plants  with  TSS
data  listed  in Table 25 and eleven of the thirty-two plants for
which data were available meet which TSS effluent limitation.

The grease effluent limitation of 0.20 kg grease/kkg LWK is based
upon a limiting effluent grease concentration of 10 mg/1 and  the
average  water  flow  per  unit of LWK for all chicken processing
plants of 35 1  (9.3 gal) per bird  (see Section V).  Of  the  five
plants  listed  in  Table  25, three meet this limitation; of the
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twenty chicken processing plants for which final grease data were
available, nine meet the limitation.  The limiting  concentration
for  grease  of 10 mg/1 was also found to be limiting for the red
meat processing industry,19 even  though  the  wastes  from  this
industry  typically have higher raw grease concentrations than do
those from the poultry industry.
Turkey

The BQD5 effluent limitation for turkeys of 0..39  kg/kkg  LWK  is
slightly  higher  than  the  average  of  the lowest three values
listed in Table 25 for turkey plants.  Using  the  average  waste
water flow for turkey processors of 118 1 (31,2 gal)  per bird and
an average turkey weight of 8.3 kg  (18.2 Ib) , this corresponds to
a final BOD5 concentration of about 28 mg/1,

The  suspended  solids effluent limitation for turkeys of 0.57 kg
TSS/ kkg LWK is the average of the three lowest  values  for  TSS
listed in Table 25 for turkey plants.  Using the average flow per
unit  LWK for turkeys, this limitation corresponds to a final TSS
concentration of 40 mg/1.

The grease effluent limitation for turkey processing of  0.14  kg
grease/  kkg  LWK was calculated using the average water flow per
unit LWK and the limiting grease concentration of 10 mg/1.   Four
of  the  five turkey plants listed in Table 25 meet this effluent
limitation and the fifth comes very close with a value of 0.17 kg
grease/kkg LWK.  These five turkey  processing  plants  were  the
only  ones  included  in the study for which data on final grease
loads were available.
Fowl

The BOD5 effluent limitation  for  fbwl  processing  of  0.61  kg
BOD5/kkg LWK was obtained by applying to a typical BOD5 raw waste
load  of  12,2  kg BOD5/ kkg LWK a waste reduction of 95 percent.
Unfortunately, a comparison with actual performance data  is  not
possible  because  no fowl processing plants discharging directly
to surface waters  could  be  located.   However,  based  on  the
similarity  between  fowl  and  chicken processing in waste water
flows,  bird  size,  and  processes   employed,   this   effluent
limitation appears reasonable.

The  suspended solids effluent limitation of 0.72 was obtained by
using the regression equation between BOD15 and TSS developed with
data for chicken processing and the BODJi limitation for  fowl  of
0.61 kg BODj>/kkg LWK.  The grease effluent limitation  >f 0.15 was
calculated using an average flow of 32.9 1 (8«7 gal)  er bird, an
average  bird  weight  of  2.2 kg  (4*8 Ib), and a limiting grease
concentration of 10 mg/1.  Again, no actual performance data  for
TSS and grease were available for comparison.


                              163

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Ducks

The  BOD^  effluent   limitation  for ducks of 0.77 was calculated
using the average waste water flow per unit LWK  and  a  limiting
final BODjS concentration of  30 mg/1.  The TSS effluent limitation
was  calculated  using the BOD5-TSS regression equation developed
from waste water data on chicken processing plants and  the  duck
processing  BOD5  limitation of 0.77 kg BOD5/kkg LWK.  The grease
effluent limitation of 0.26  kg grease/  kkg  LWK  was  calculated
from  the  average  waste  water  flow  per unit LWK and a grease
limiting concentration of 10 mg/1.  One Of  two  duck  processing
plants for which treatment effluent data were available meets all
three  of  these  effluent   limitations.   This  plant  meets the
effluent limitations  in spite of the fact that the final effluent
included the waste water from an onsite duck feedlot.
Further Processing Only

Since slaughtering processes are  not  involved,  the  regression
procedures  were  not  directly applied to this subcategory.  The
effluent limitations for further  processing  plants  were  based
upon   the   average   waste   water   flow  and  final  effluent
concentrations of 30, 35, and 10 mg/1 for BOD5, TSS, and  grease,
respectively.   The BOD^ concentrations are considered attainable
with current technology based on BOD5 reduction  demonstrated  in
other  subcategories with similar raw waste characteristics.  The
grease is a limiting value, and a check of  validity  showed  the
TSS concentration corresponds to a value predicted from the BOD5.-
TSS  regression  equation  developed from final effluent data for
chicken processing plants using  the  BOD5  concentration  of  30
mg/1.  In addition, all three of these effluent limitation values
are  close  to  those  recommended for those segments of the meat
processing industry having  operations  similar  to  those  of  a
poultry further processing only plant,*0


      ENGINEERING ASPECTS OF CONTROL TECHNIQUE APPLICATIONS

The  specific  level of control technology* in-plant primary plus
biological treatment, is  practicable  because  it  is  currently
being  practiced  by  plants  representing  a wide range of plant
sizes and types.  However, if  additional  treatment  is  needed,
such as sand filters, mixed-media filter beds, or microstrainers,
this  technology  is  practical  as evidenced by its use in other
industries,1* in municipalities, and in the poultry industry.


                         PROCESS CHANGES

Significant in-plant changes will  not  be  needed  by  the  vast
majority  of  plants  to  meet  the  limitations specified.  Many
plants will  have  to  improve  plant  cleanup  and  housekeeping
practices,  both of which are responsive to good plant management
control.   This  can  best  be  achieved  'by  minimizing  spills,

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containing  and collecting materials, and the use of dry cleaning
prior to washdown.  Some plants may find it necessary to pretreat
offal holding truck drainage before mixing it  with  other  waste
waters  for  recycle, after screening, through the feather flume,
and to keep blood  segregated  from  feathers  and  offal.   Some
plants  may  also  find  it  necessary  to  use  improved gravity
separation systems, such as air flotation with chemical additions
for in-p.1 ant primary treatment.


              NONWATER QUALITY ENVIRONMENTAL IMPACT

The major impact on the  environment  will  be  disposal  of  the
sludge  from an activated sludge type of treatment system or from
chemical precipitation in  in-plant  primary  treatment.   Nearby
land for sludge disposal may be necessary; in some cases a sludge
digester  (stabilizer)  may  offer a solution.  Properly operated
activated sludge-type systems  should  produce  well  conditioned
sludge  acceptable  for  placement in small nearby soil plots for
drying without great difficulty.  it was concluded that the  odor
emitted  periodically  from  anaerobic  lagoons  is  not  a major
impact.
                                 165

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                            SECTION X

    EFFLUENT REDUCTION ATTAINABLE THROUGH THE APPLICATION OF
     THE BEST AVAILABLE TECHNOLOGY ECONOMICALLY ACHIEVABLE—
                 EFFLUENT LIMITATIONS GUIDELINES
                          INTRODUCTION

The effluent limitations which must be  achieved  no  later  than
July 1, 1983, are not based on an average of the best performance
within  an industrial category, but are determined by identifying
the very best control and  treatment  technology  employed  by  a
specific   point   source   within  the  industrial  category  or
subcategory, or by one industry where it is readily  transferable
to   another.   A  specific  finding  must  be  made  as  to  the
availability of control measures and the practices  to  eliminate
the discharge of pollutants, taking into account the cost of such
elimination.

Consideration was given to:

     o  The age of the equipment and facilities involved;

     o  The process employed;

     o  The engineering aspects of the application of various
        types of control techniques;

     o  Process changes;

     o  The cost of achieving the effluent reduction resulting
        from application of the technology;

     o  Nonwater quality environmental impact  (including energy
        requirements).

Best  AvailabJe Technology Economically Achievable emphasizes in-
process controls as  well  as  control  or  additional  treatment
techniques employed at the end of the production process.

This  level  of  technology  considers  those plant processes and
control technologies which, at the pilot-plant,  semi-works,  and
other  levels,  have demonstrated both technological performances
and economic  viability  at  a  level  sufficient  to  reasonably
justify  investing  in such facilities.  It is the highest degree
of  control  technology  that  has  been  achieved  or  has  been
demonstrated  to  be  capable  of  being designed for plant-scale
operation up to  and  including  "no  discharge"  of  r ollutant.s«
Although economic factors are considered in this development, thr-
costs of this level of control are intended to be the top-of-the-
line  of  current  technology,  subject  to limitation imposed by
economic and engineering feasibility.  However, there may be rsorne
technical risk with respect to performance and  with  respecr  to
                            167

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certainty  of  costs.   Therefore,  some  industrially  sponsored
development work may be needed prior to its application.


    EFFLUENT REDUCTION ATTAINABLE THROUGH APPLICATION OF THE
        BEST AVAILABLE TECHNOLOGY ECONOMICALLY ACHIEVABLE

Based on  the  information  contained  in  this  section  and  in
Sections  III  through  VIII  of this report, a determination has
been made that the quality of  effluent  attainable  through  the
application   of   the  Best  Available  Technology  Economically
Achievable is as listed in Table 26.  The technology  to  achieve
these goals is generally available, and has been used by at least
one poultry processing plant on a full-scale.  Plants with onsite
rendering  and  further processing  (but not including cut-up only
operations) in addition to slaughtering require an adjustment  in
the  BODjj,  TSS,  and  grease  limitations.   The  adjustment for
further processing is the value for further processing only given
in Table 26; the adjustment for  onsite  rendering  includes  the
values  developed  for  the off-site rendering industry,39  These
adjustment factors are presented in Table  27.   Adjustments  for
further  processing  are  only permitted for that part of further
processing  that  includes   cooking.    This   excludes   cut-up
operations.   The  reason for this is that the raw effluent waste
loads for  plants  with  only  slaughtering  operations  are  not
distinctively  different  from  the  waste  loads  of plants with
slaughter plus cut-up operations  (see  Section  IV) .   Adjustment
factors  for  duck  feedlots are not included for duck processors
who also raise ducks, because the  feedlot  industry  limitations
require no discharge from duck feedlots by 1983.*i

Adjustment   factors  do  not  have  a  material  effect  on  the
limitations, unless the amount of further processing or rendering
relative to the live weight killed is significant.  For  example,
if a broiler slaughter operation kills birds of an average weight
of  1.7  kg  (3.8 Ib) and renders onsite all of the offal from the
slaughtering operation at the rate of 0.45 kg (1  Ib)  offal  per
bird, the adjustment factors  (AF) are:

  AF(BOD5)  = 0.07 x 0.45  - 0.018 kg/kkg LWK or 0.018 lb/1000 Ib LWK
                    1.7

  AF(TSS)    = 0-10_x 0.45 = 0.026 kg/kkg LWK or 0.026 lb/1000 Ib LWK
                    1.7

  AF(Grease)= O.Q5 x 0.45 = 0.013 kg/kkg LWK or 0.013 lb/1000 Ib LWK
                    1,7

The   adjusted  effluent  limitations  for  this  plant  are  the
corresponding limitations from Table  26  added  to  those  AF(s)
above,  which  are  0.30 * 0.018  or 0.318 kg BOD5/kkg LWK; 0.34 +
0.026 or 0.366 kg TSS/kkg LWK; and  0.20  +  0.013  or  0.213  kg
grease/kkg LWK.
                            168

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              Table 26.  Recommended Effluent Limitation Guidelines for July 1, 1983
Industry
Subcategory
Chickens
Turkeys
Fowl
Ducks
Further
Processing
Only
BOD 5
kg/kkg LWK*
0.30
0.21
0.23
0.39
0.15
SS
kg/kkg LWK
0.34
0.24
0.27
0 = 46
0.13
Greasa
kg/kkg LWK
0.20
0.14
0.15
0.26
0.10
NH3
mg/1
4
4
4
4
4
Fecal Coliforms
counts/100 ml
400
400
400
400
400
*kg/kkg LWK is equivalent to lb/1000 Ib LWK.

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      Table 27.   Effluent Limitation Adjustment Factors for On-Site
                 Rendering and Further Processing*
Effluent
Parameters
BOD5
Suspended
Solids (SS)
Grease
Adjustment Factors
For On-Site Rendering**
0.07 kg BOD^
kkg RM X
0.10 kg SS
kkg RM A
0.05 kg grease
kkg RM
(kkg RM)
(kkg LWK)
(kkg RM)
(kkg LWK)
(kkg RM)
(kkg LWK)
For Further
0.15 kg BODS
kkg FP
0.18 kg SS
kkg FP
0.10 kg grease
kkg FP
Processing
.. (kkg FP)
" (kkg LWK)
.. (kkg FP)
A (kkg LWK)
v (kkg FP)
" (kkg LWK)
 *For processes including a cooking step,  but not for cut-up only
  operations.
**RM—Raw Materials Rendered.

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Similarly,  the  adjustment  factors for a broiler operation that
slaughters 73,000 birds per day at an average weight  of  1.7  Kg
(3.8 Ib)  per bird and further processes 25,000 birds per day with
an average product yield per bird of 0D76 kg  (1.7 Ib) FP are;
AF(BOD5)  = 0.15
                      25TQOO x 0.76 = 0.022 kg/kkg LWK
                      73,000 x 1.74
                                  or  0,022 lb/1000 Ib LWK
AF(SS)
               0.18 x 25,000 x 0..76 = 0.027 kg/kkg LWK
                      73,000 x 1.74
                                  or  0.027 lb/1000 Ib LWK
   AF(Grease)^ 0.10 x 25P000_ x. 0.76 * 0.015 kg/kkg LWK
                      73,000 x 1.74
                                  or  0*015 lb/1000 Ib LWK

The adjusted effluent limitations for this plant would be;  0.30 +
0.022 or 0.322 kg BOD5/kkg LWK; 0.34 * 0*027 or 0.367 kg TSS/kkg LWK;
and 0.20 + 0,015 = 0.215 kg grease/kkg LWK.

In general then, for onsite rendering the adjustment in effluent
limitations is Only significant when a plant renders raw material from
other plants in addition to its own.  This practice occurs occasionally
in the poultry processing industry*  For further processing adjustment
factors to be significant, a plant would have to further process the
majority of its LWK,
                               171

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           IDENTIFICATION OF BEST AVAILABLE TECHNOLOGY
                     ECONOMICALLY ACHIEVABLE

The  Best  Available  Technology Economically Achievable includes
the  biological  treatment  systems   listed   under   the   Best
Practicable  Control Technology Currently Available (Section IX),
and "polishing" by means of  a  sand  filter,  microstrainer,  or
equivalent  following  biological  treatment.   In addition, some
plants will require improved pretreatment, such as dissolved  air
flotation  with  pH  control  and chemical flocculation, and many
will    require     ammonia     control     by     nitrification,
nitrification/denitrification or stripping.

In-plant  controls  and  modifications  may  also  be required to
achieve the specified levels.  These include the following:

     o  Appoint a person with specific responsibility for water
        management.  This person should have reasonable powers to
        enforce improvement in water and waste management, both
        in-plant and for treatment systems.

     o  Determine or estimate water use and waste load strength from
        principle sources.  Install and monitor flowmeters in all
        major water use areas.

     o  Control and minimize flow of freshwater at major outlets by
        installing properly sized spray nozzles and by regulating
        pressure on supply lines.  On hand washers, this may require
        installation of press-to-operate valves.  This also implies
        that screened waste water is recycled for feather fluming.

     o  Stun birds in the Killing operation to reduce carcass
        movement during bleeding.

     o  Confine bleeding and provide for sufficient bleed time.
        Recover all collectable blood and transport to rendering in
        tanks rather than i>y dumping on top of feathers or offal.

     o  Use minimum USDA approved quantities of water in the scalder
        and chillers.

     o  Shut off all unnecessary water flow during work breaks.

     o  Consider the reuse of chiller water for makeup water for the
        scalder.  This may require preheating the chiller water with
        the scalder overflow water by using a simple heat exchanger.

     o  Use pretreated poultry processing waste waters for condensing
        all cooking vapors in onsite rendering operations.

     o  In-plant primary systems—catch basins, skimming tanks, air
        flotation, etc.—should provide for at least a 30-minute
        detention time of the waste water.
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o  Avoid over-filling cookers in rendering operations.

o  Provide and maintain traps in the cooking vapor lines of
   rendering operations to prevent overflow to the condensers,
   This is particularly important when the cookers are used
   to hydrolyze feathers,

o  Provide by-pass controls in rendering operations for controlling
   pressure reduction rates of cookers after feather hydrolysis.
   Cooker agitation may have to be stopped also, during cooker
   pressure bleed-down to prevent or minimize materials carry-over.

o  Consider dry offal handling as an alternative to fluming.  A
   number of plants have demonstrated the feasibility of dry offal
   handling in modern high-production poultry slaughtering
   operations,,

o  Consider steam scalding as an alternative to immersion scalding.

o  Control water use in gizzard splitting and washing equipment.

o  Provide for regular and frequent maintenance attention to by-
   product screening and handling systems.  A back-up screen may
   be required to prevent byproduct from entering municipal or
   private waste treatment systems,,

o  Treat offal truck drainage before sewering.  One method is to
   steam sparge the collected drainage and then screen,

o  Dry clean all floors and tables prior to washdown to reduce
   the waste load.  This is particularly important in the bleeding,
   cutting, and further processing areas and all other areas
   where there tends to be material spills.

o  Use high-pressure^ low-volume spray nozsles or steam augmented
   systems for plant washdown„

o  Minimize the amount of chemicals and detergents to prevent
   emulsification or solubilizing of solids in the waste waters,
   For examplep determine the minimum effective amount of chemical
   for use in the scald tank.

o  Control inventories of raw materials used in further processing
   so that none of these materials ^;re ever wasted to the sewer.
   Spant raw materials should be routed to rendering,

o  Separately treat all overflow of cooking broth for grease and
   solids recovery,

o  Reduce the waste water from thawing operatior ;.

o  Make all employees aware of good water management practices
   and encourage them to apply these practices.
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If  suitable  land  is  available,  land  disposal  is  the  best
technology;  it  is  no discharge.  However, biological treatment
may still be required before disposal of waste  waters  to  soil,
although  the  degree  of  treatment need not be the same as that
required to meet the 1977 limitations (Section IX).  Any  of  the
systems mentioned in Section IX are suitable.


          RATIONALE FOR SELECTION OF THE BEST AVAILABLE
               TECHNOLOGY ECONOMICALLY ACHIEVABLE

The  rationale  used in developing the BODji, suspended solids and
grease effluent limitations presented in Table 26 were based upon
actual performance data of a poultry processing  waste  treatment
system  and  upon  the  average  raw  waste  water flows for each
subcategory.  The particular system whose performance was used to
establish these limitations included flow equalization, dissolved
air  flotation  with   chemical   addition,   activated   sludge,
microstrainers,  and  a chlorination basin.  This system was able
to produce an effluent of 15, 18, and 10 mg/1 of BOD5,  TSS,  and
grease,  respectively.  Other systems, tut without advanced waste
treatment,  were   also   able   to   achieve   some   of   these
concentrations, but never all three for any one system.

The  Kjeldahl  nitrogen,  ammonia nitrogen, total phosphorus, and
nitrite-nitrate effluent limitations are based upon  transfer  of
waste  treatment technology from the red meat industry19 and from
the off-site rendering industry.39  These industries, which  have
similar  raw  waste  characteristics, were able to reach limiting
concentration values for these  waste  parameters  using  similar
waste  treatment  systems.  These limiting concentrations are the
effluent limitation values  shown  in  Table  26.   A  number  of
poultry  processing  plants  were  able to achieve these limiting
concentrations.   However,  the  ammonia  and  Kjeldahl  nitrogen
limiting concentrations appear to be the most difficult to meet.

The  fecal coliform effluent limitations of UOO counts/100 ml was
established because all plants having adequate chlorination  were
within this limit.

Because  of  the  rationale  used  to establish the 1983 effluent
limitation, two major approaches to reducing the  final  effluent
waste  load  can  be  used  by  the industry.  The first and most
economical approach is to reduce the waste water flow rate  to  a
value well below the averages found in this study  (see Section V)
by   the   use  of  in-plant  controls  and  conscientious  waste
management.  The second is to improve the waste treatment systems
to achieve a greater  reduction  in  waste  strength.   The  most
practical  approach  however will undoubtedly be a combination of
the two.
                              174

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                 AGE OF EQUIPMENT AND FACILITIES

The age of plants and  equipment  does  not  affect  the  end-of-
process   pollution  control  effectiveness„    Although  in-plant
control can be managed guit§ effectively in older plants,:some of
the  methods  capable  of  reducing  the  raw  waste   loads   to
realistically  low  levels may be more costly tc install in older
Plants.
                    TOTAL COST OF APPLICATION

Based on information contained in Section VIII  of  this  report,
the  incremental  investment: cost above 1977 costs to the poultry
industry to implement the waste treatment  to  achieve  the  1983
effluent  limitations  is  estimated  to  be $38=6 million.  This
amounts to 6U  percent  of  total  capital  expenditures  of  $60
million  by  the  industry in each of the three years 1970, 1971,
and 1972.

The additional operating  cost  associated  with  achieving  1983
limitations  for chicken^ turkeyF and fowl processors varies from
0.30/bird to 3#/bird and for duck processors  from  2.82/bird  to
8.2£/bird.    Plants   that   further  process  only  will  incur
additional operating costs from 0*29  to  0.730/Kg  FP   (0-13  to
0.352/lb  FP) ,.   The  total  annual  cost  increase  per  unit of
production to achieve 1983 limitations varies between 2=5 and 2.6
times the operating cost  increase,,   The  large  plants  in  the
industry  will  experience  the  lower  cost increase per unit of
production.
      ENGINEERING ASPECTS OF CONTROL TECHNIQUE APPLICATION

The specific level of effluent is achievable.  Several plants are
currently meeting a number of the 1983 effluent limitations.  On«
plant  (which includes a microstrainer  for  advanced  removal  of
suspended  solids) is currently achieving or nearly achieving all
limitations.  Howeverff nitrification has been achieved in  pilot-
and  full-scale  units.,   Denitrification  has been explored with
some success in  laboratory  and  pilot-scales.   Field  sampling
surveys      of      rendering      plants      revealed     that
nitrification/denitrification  was  occurring  in  large   lagoon
systems  if  they  were  npt overloaded,39  Ammonia stripping may
require pH adjustment and later neutralisation;  recent  advances
in  the  operation  of  the process make it feasible for possible
utilization.

Each of the identified technologies,, except ammonia  removal  and
nitrification/denitrification,  is  currently  being practiced in
the  poultry  products  industry„   They  need  to  be  combined/
however, to achieve the limits specified.
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Two  poultry plants in our sample are irrigating with their waste
water.  Technology for land disposal by irrigation is being  used
by  rendering  plants  and  by  meat  processing and meat packing
plants, primarily in the Southwest and California.  It  has  also
been  used  successfully in northern Iowa by rendering plants and
it  is  being  planned  for  a  packing  plant  in  Iowa.   Other
industries,  e.g.,  potato  processing, are using it extensively.
Secondary treatment and large holding ponds may  be  required  in
the  north  for  land disposal during about one-half of the year.
Application of technology  to  reduce  in-plant  water  use  will
facilitate land disposal alternatives.


                         PROCESS CHANGES

In-plant  changes  will  be  necessary  or  will  be  found to be
advantageous, for most  plants  to  meet  the  limits  specified.
These  were outlined in the "Identification of the Best Available
Technology Economically Achievable," previously.


                     NONWATER QUALITY IMPACT

None of the additional  technology  required  to  meet  the  1983
limitations  is energy intensive.  The primary energy consumption
occurs in pumping the waste water and the other material  streams
in  the treatment processes.  Electrical energy usage is expected
to increase about 60 million KWH  per  year  above  current  (and
projected 1977) levels.  This amounts to only about 1.0% of total
power consumption for the industry.

The  major  impact  will  occur  when the land disposal option is
chosen.  The potential long-term effect on  the  soil  caused  by
irrigation  of  processing plant wastes is unknown.  On the other
hand, the wastes are among the most amenable to land disposal and
irrigation has been done  successfully  by  one  California  meat
processing  plant  for  over  30 years.  The impact will probably
depend on location, soil conditions, waste strength, climate  and
other factors.
                             176

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                           SECTION XI

                NEW SOURCE PERFORMANCE STANDARDS


                          INTRODUCTION

The effluent limitations that must be achieved by new sources are
termed  performance  limitations.   The  New  Source  Performance
Standards apply to any source for which construction starts after
the promulgation and publication of the proposed  regulations  as
Standards.   The  Standards  are  determined  by  adding  to  the
considerations  underlying  the  identification   of   the   Best
Practicable    Control    Technology   Currently   Available,   a
determination of what higher  levels  of  pollution  control  are
available  through  the  use  of  improved  production processes,
and/or treatment techniques.,  Thus, in  addition  to  considering
th<*  best  in-plant  and  end-of-process  control technology. New
Source Performance Standards are based on an analysis of how  the
level  of  effluent  may  be  reduced  by changing the production
process itself.  Alternative  processes,  operating  methods,  or
other  alternatives  are  considered.  However, the end result of
the analysis is to identify effluent  limitations  which  reflect
levels   of  control  achievable  through  the  use  of  improved
production  processes  and  practices   fas   well   as   control
technology)  rather than prescribing a particular type of process
or technology which kirast be employed*  A further determination is
made whether a limitation permitting no discharge  of  pollutants
is practicable.

Consideration must also be given tos

     o  Operating methods;

     o  Batchff as opposed to continuous? operations;

     o  Use of dry rather than wet processes or expanded reuse of
        water by cascading through the plant;

     o  Recovery of pollutants as byproducts.


          EFFLUENT REDUCTION ATTAINABL5LFQR NEW SOURCES

The  effluent  limitations  for new sources are the same as those
for the Best Practicable Control Technology  Currently  Available
(see  Section IX).  In additionff ammonia effluent limitations are
required*  The ammonia limitation is based on an ammonia nitrogen
concentration of 10 mg/1 and the same wast:e water flc  rates  per
unit  LWK as used in Section IX.  The new source amm *iia effluent
limitations for the five categories ares
                           177

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       Category

       Chickens

       Turkeys

       Fowl

       Ducks

       Further Processing Only
       Ammonia as N
   Effluent Limitation,
Kq/kkq LWK, (lb/1000 Ib LWK)

           0.20

           0.14

           0.15

           0.26

           0.10
The effluent limitations for ammonia are  readily  achievable  in
newly  constructed  plants  as  demonstrated  by  the fact that a
number  of  existing  well-operated  plants  are  meeting   them.
However,  the  limitations  for  the  Best  Available  Technology
Economically Achievable should be kept in mind; it may be a  more
practical  approach  to  design a plant which approaches the 1983
limitations.   Consideration  should  also  be  given   to   land
disposal,  which  would be no discharge.  In some situations this
will be the most attractive and economical option.  Estimates  of
capital  investment  cost,  operating cost, and total annual cost
for waste treatment by new point  sources  are  listed  for  each
subcategory in Table 28.


         IDENTIFICATION OF NEW SOURCE CONTROL TECHNOLOGY

The  technology  is  the  same  as  that  identified  as the Best
Practicable Control Technology Currently Available  (see  Section
IX).   However,  certain steps that will be necessary to meet the
1983  guidelines  should  be  considered  and,  where   possible,
incorporated.  These include:


In-Plant Controls

      o  Control and minimize flow of freshwater at major outlets by
         installing properly sized spray nozzles and by regulating
         pressure on supply lines.  Hand washers may require installa-
         tion of press-to-operate valves.  This also implies that
         screened waste waters are recycled for feather fluming.

      o  Stun birds in the killing operation to reduce carcass
         movement during bleeding.

      o  Confine bleeding and provide for sufficient bleed time.
         Recover all collectable blood and transport to rendering
         in tanks rather than by dumping on top of feathers or offal.

      o  Use minimum OSDA-approved quantities of water in the scalder
         and chillers.
                              178

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Table 28.  Capital Investment, Operating and Total
           Annual Costs for New Point Sources
Plant Type
Chicken
Small
Medium
Large
Turkey
Fowl
Small
Large
Duck
Small
Large
Further Processing
Only
Small
Large
Capital
Investment

$470,000
640,000
950,000
400,000

364,000
529,000

227,000
385,000

225,000
364,000
Operating
Cost per Year

$54,000
67,100
90,400
48,300

45,400
59,700

35,300
46,400

35,100
45,400
Total Annual
Cost per Year

$148,000
195,100
280,400
128,300

118,200
167,500

80,700
123,400

80,100
118,200
                     179

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o  Shut off all unnecessary water flow during work breaks.

o  Consider the reuse of chiller water as makeup water for the
   scalder.  This may require preheating the chiller water with
   the scalder overflow water by using a simple heat exchanger.

o  use pretreated pqultry processing waste waters for condensing
   all cooking vapors in onsite rendering operations.

o  Consider dry offal handling as an alternative to fluming.  A
   number of plants have demonstrated the feasibility of dry offal
   handling in modern higb-prcduction poultry slaughtering
   operations.

o  Consider steam scalding as an alternative to immersion scalding.

o  Control water use in gizzard splitting and washing equipment.

o  Provide for frequent and regular maintenance attention to by-
   product screening and handling systems.  A back-up screen may
   be required to prevent byproduct from entering municipal or
   private waste treatment systems.

o  Dry clean all floors and tables prior to washdown to reduce
   the waste load.  This is particularly important in the bleeding,
   cutting, and further processing areas and all other areas where
   there tend to be material spills.

c  Use high-pressure, low-volume spray nozzles or steam-augmented
   systems for plant washdown,

o  Minimize the amount of chemicals and detergents to prevent
   emulsification cr solubilizing of solids in the waste waters.
   For example, determine the minimum effective amount of chemical
   for use in the scald tank.

o  Control inventories of raw materials used in further processing
   so that none of |:hese materials are ever wasted to the sewer.
   Spent raw materials should be routed to rendering,

o  Treat separately all overflow of cooking broth for grease and
   solids recovery.

o  Reduce the waste water from thawing operations.

o  Make all employees aware of good water management practices
   and encourage them to apply these practices.

o  Treat offal truck drainage before sewering.  One method is
   to steam sparge the collected drainage and then screen.

o  In-plant primary systems—catch basins, skimming tanks, air
   flotation, etc.—should provide for at least a 30-minute
   detention time of the waste water.  Frequent, regular

                        180

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         maintenance attention should be provided.
End-of-Process Treatment

      o  Land disposal by irrigation should be a primary consideration
         wherever possible.

      o  Sand filter or microscreen following biological treatment of
         ef fluent«,

      o  Solid waste drying, composting, and upgrading of protein
         content.
                    PRETREATMENT REQUIREMENTS

No  constituents  of  the effluent discharged from a plant within
the poultry processing  industry  have  been  found  which  would
interfere withff pass through^ or otherwise be incompatible with a
well-designed  and  operated^  publicly-owned activated sludge or
trickling filter waste  water  treatment  plant*   The  effluent,
however^  should  have  passed through byproduct recovery and in-
plant primary treatment in the plant to remove settleable  solids
and   most  of  the  grease«   The  concentration  of  pollutants
acceptable to the municipal treatment plant is dependent  on  the
relative   sizes  of  the  treatment  facility  and  the  poultry
processing plant,  and  must,  be  established  by  the  treatment
facility.   It  is  possible  that  grease remaining in the plant
effluent may cause difficulty in the treatment system;  trickling
filters  appear to be particularly sensitive,  A concentration of
100 mg/1 is often cited as a  limitg  and  this  may  require  an
effective  air flotation system in addition to a catch basin.  If
the waste strength* in terms of BQD5ff must  be  further  reduced,
any of the various components of biological treatment systems can
be  used,  such  as  anaerobic contact*, trickling filter, aerated
lagoonsff etc,e as pretreatment0
                             181

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                           SECTION XII

                         ACKNOWLEDGMENTS

The program was conducted under the overall supervision of Dr. E.
E.  Erickson.  Robert J. Reid was the Project  Engineer;  he  was
assisted  by  Messrs. J. P. Pilney and Robert J. Parnow.  Special
assistance was provided by North Star staff members:   Mrs.  Mary
Weldon,   Messrs.   R.  H.   Forester,  A.  J.  Senechal,  R.  F,
Colingsworth, and Dr,. L. L. Altpeter.

The contributions and advice of Mr. Jbhn A. Macon, Mr. William J.
Camp of Gold Kist Poultry and Mr.  Gary  J.  Bottomley  of  Holly
Farms Poultry are gratefully acknowledged.  Also, James and Paula
Wells of Bell, Galyardt, & Wells made invaluable contributions in
numerous telephone conversations.

Special  thanks are due Mr. Jeffery D* Denit, Effluent Guidelines
Division for his guidance in the direction of the program and for
his invaluable help in carrying out all aspects of  the  research
program.

The  cooperation  of  the  poultry processing industry is greatly
appreciated.   The  National  Broiled  Council,  Poultry  Science
Association,  Poultry  and Egg Institute of America, Southeastern
Poultry and  Egg  Association,  Poultry  Industry  Manufacturer1s
Council,    Arkansas   Poultry   Association,   National   Turkey
Federation,  Pacific  Egg  and  Poultry  Processers  Association,
Mississippi  Poultry Improvement Association, and Alabama Poultry
and Egg Association deserve special m'ention, as do many companies
that provided information and cooperation  in  plant  visits  and
onsite sampling programs.

Various  offices  in the United States Department of Agriculture,
especially the Meat and Poultry  Inspection  Division,  and   many
State  and  local  agencies  were  also  most  helpful  and   much
appreciated.
                               182

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                          SECTION XIII

                           REFERENCES
1.  "The Poultry Processing Industry:  A Study of the impact of Water
    Pollution Control Costs," USDA, Economic Research Service, in
    cooperation with EPA& Marketing Research Report No. 965,
    Washington, June 1972.

2.  "Plants Under Federal Inspection Kise Again in Chaotic Calendar
    1973 But Not Muchff" The National Provisioner, March 2, 1974.

3.  "Agricultural Statistics, 1972," United States Department ox
    Agriculture, United States Government Printing Office, Washington
    1972.
9.
    "197U Poultry Industry Directory,
    Association,
                                   Southeastern Poultry & Egg
5.  Porges R0 , "Wastes from Poultry Dressing Establishments,"
Sewage and Industrial Wastes,, 220 No
                                             521  (April 1950) .
Porgesff R., and Struzeski, E« J0, Jr«, "Wastes from the Poultry
Processing Industry," The Robert A. Taft Sanitary Engineering
Center, Technical Report W£2-3

"U.S=,  Industri.
Department of <
Washington,
                   1 Outlook, 1974 „ with Projections to 1980," U.S.
                   :ommerce, U0S0 Government Printing Office,
    "1967 Census of Manufacturers,"  (and 1971 Supplement) Bureau
    of the Census^ u, S. Department of Commerce, U0 S.
    Government Printing Office, Washington,,
"In-Process Pollution Abatement:
Facilities to Reduce Pollution,"
Publication, July 1973.
                                  Upgrading Poultry-Processing
                                 EPA Technology Transfer Seminar
10. Personal Communication with G. J, Bottomley, 1974,

11, "Basics of Pollution Controlff" Gurnham & Associates, prepared for
    Environmental Protection Agency Technology Transfer Program, Kansas
    City, Mo*, March 7-8ff 1973ff Chicago* Illinois.

12. "Public Health Service Drinking Water Standards  Revised 1962,"
    U.S. Department of Health, Education and Welfa: ^, U.Sa Public
    Health Service Publication No. 956ff UoS0 Cover ment Printing
    Office,, Washington, 1962,

13.  Steffen, A0J0, "In-Plant Modifications to R duce Pollution and Pre-
     treatment of Meat Packing Wastewaters for Discharge to Municipal
     Systems," prepared for Environmental Protection Agency Technology
     Transfer Program, Kansas City, Mo., March 7-8, 1973.
                               183

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14.  "Pretreatment of Poultry Processing Wastes"  Upgrading Poultry-
     Processing Facilities to Reduce Pollution, EPA Technology
     Transfer Seminar Publication, July 1973.

15.  "Water Quality Improvement by Physical and Chemical Processes,"
     Earnest F. Gloyna and W. Wesley Eckenfelder. Jr., Eds., University
     of Texas Press, Austin, 1970.

16.  Rosen, G.D., "Profit from Effluent," Poultry Industry (April 1971).

17.  Personal communication with J. Hesler, Greyhound Corporation, 1973.

18.  Telephone communication with M. Hartman^ Infilco Division,
     Westinghouse, Richland, Virginia, May 1973,

19,  "Development Document for Effluent Limitations Guidelines
     and New Source Performance Standards for the Red Meat Processing
     Segment of the Meat Product and Rendering Processing Point Source
     Category," U.S. Environmental Protection Agency, Report No, 440/1-
     74/012-a, Washington, February, 1974.

20.  E.G. Beck, A.F. Giannini, and E.R. Ramirez, "Electrocoagulation
     Clarifies Food Wastewater," Food Technology. Vol. 28, No. 2,
     Pages:  18-22, 1974.

21.  "Upgrading Meat Packing Facilities to Reduce Pollution:  Waste
     Treatment Systems," Bell, Galyardt, Wells, prepared for Environ-
     mental Protection Agency Technology Transfer Program, Kansas City,
     Mo., March 7-8, 1973, Omaha.

22.  Private communication from Geo, A. Hormei & Company, Austin,
     Minnesota, 1973.

23.  Chittenden, Jimmie A., and Wells, W. James, Jr., "BOD Removal and
     Stabilization of Anaerobic Lagoon Effluent Using a Rotating Bio-
     logical Contactor," presented at the 1970 Annual Conference, Water
     Pollution Control Federation, Boston.

24.  Gulp, Russell L., and Gulp, Gordon L., "Advanced Wastewater Treat-
     ment," Van Nostrand Reinhold Company, New York, 1971,

25.  Babbitt, Harold E., and Baumann, E. Robert, "Sewerage and Sewage
     Treatment," Eighth Ed., John Wiley & Sons, Inc., London, 1967.

26.  Fair, Gordon Maskew, Geyer, John Charles, and Okun, Daniel
     Alexanders "Water and Wastewater Engineering:  Volume 2.  Water
     Purification and Wastewater Treatment and Disposal," John Wiley
     6 Sons, Inc., New York, 1968.

27.  Personal communication with H.O. Halvorson, 1973.

28.  Fair, Gordon Maskew, Geyer, John Charles, and Okun, Daniel
     Alexander, "Water and Wastewater Engineering:  Volume 1.  Water
     Supply and Wastewater Removal," John Wiley & Sons, Inc., New
     York, 1966.

                               184

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29,   Eckenfelder, W.  Wesley,  Jr., "Industrial Water Pollution Control,"
     McGraw-Hill Book company. New York, 1966.

30,   Eliassen, Rolf and Tchobanoglous, George, "Advanced Treatment
     Processes," Chemical Engineering, (October 14, 1968),

31,   Knowles, Chester L., Jr., "Improved Biological Processes,"
     Chemical Engineering/Deskbook Issue (April 27, 1970).

32.   Personal communication,  H,O. Halvorson, May 1973,

33.   Mccarty, P.L, , "Anaerobic Waste Treatment Fundamentals—Part Two,
     Chemistry and Microbiology," Public Works, 95, 123  (October 1964.

34.   Personal communication with Lowell Hanson, Soil Science,
     Agricultural Extension Service, University of Minnesota, 1973.

35.   Personal communication,  C.E. clapp. United states Department of
     Agriculture, Agricultural Research Service, University of
     Minnesota, Minneapolis,  May 1973.

36.   "Preliminary Report, 1972 Census of Manufacturers Industry Series,"
     A United States Department of commerce Publication, March 1974.

37.   "Financial Facts About the Meat Packing  Industry, 1971," American
     Meat Institute, Chicago, August 1972*

38.   "Survey of Corporate Performance:  First Quarter 1973," Business
     Week, p. 97  (May 12, 1973).

39.   "Development Document for Proposed Effluent Limitations
     Guidelines and Standards of Performance  for the Renderer
     Segment of the Meat Produpts Point Source Category
     U.S. Environmental protection Agency, Washington,
     August 1974.

40.   "Development Document for Proposed Effluent Limitations
     Guidelines and standards of Performance  for the Processor
     Segment of the Meat Products Point Source Category
     Environmental Protection Agency, Washington, August 1974.

41.   "Rules and Regulations, Part 412—Feedlots Point Source Category,"
     Federal Register, 39, (32), Thursday, February 14,  1974.

42.   "Water Quality Criteria - 1972," National Academy
     of Sciences and National Academy of Engineering for the
     Environmental Protection Agency, Washington, D. G.  1972
     (U. S. Govt. Printing Office Stock No. 5501-00520).

43.   Loehr, Raymond C. Agricultural Waste Managemer' .M
     Academic Press, New York, 1974.

44,   Anthonisen, A.C., R. C. Loehr, et. al.,  "Inhibition of
     Nitrification by Unionized Ammonia and Unionized Nitrous
                              185

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     Acidr" presented at 47th Annual Conference, Water Pollution
     Control Federation, October, 19"|4.

45.  Development and Demonstration of Nutrient Removal from
	Animal Hastes EPA-R2-73-095 U. 3. Environmental Protection
     Agency, January, 1973.

46.  Prakasam, T.B.S. et alr "Approaches for the Control of
     Nitrogen With an Oxidation Ditch," Proceedings 1974
     Agricultural Waste Management conference, Cornell University,
     Ithaca, New York, pp  421-435.   j

47.  "Control of Nitrogen  in Wastewater Effluents," U. S.
     Environmental Protection Agency, ORD  (NERC) Cincinnati,
     Ohio, March 1974.

48.  "ABF Nitrification System, 1974 Pilot Plant Study," Interim
     Report, Neptune Microfloc, Inc. September, 1974.

49.  Reeves, T.G,, "Nitrogen Removal" a literature review,"
     JWPCF volume 44, No.  10 pp 1895-1908, October, 1972.

50.  Gonzales, J. G. and R. L. Gulp, !'New Developments in
     Ammonia Stripping," Public Works p. 78, May, 1973.

51.  O'Farrell, T. P. et.  al., "Nitrogen removal by ammonia
     stripping," JWPCF vol. 44, no. 8 pp 1527-1535, August,  1972.

52.  "Nitrogen Removal from Wastewaters," Federal Water Quality
     Administration, AWT Laboratory Cincinnati, Ohio May,  1970.
                                      \
53.  "Evaluation of Anaerobic Denitrification Processes" Journal
     SED, American Society of Civil Engineers pp 108-111,
     February, 1971.

54.  McLaren, J. R, and G. J, Farquhar, "Factors Affecting Ammonia
     Removal by Clinoptilolite" Jour. EED, American Society  of
     Civil Engineers, pp 429-446 Augus^:, 1973.

55.  Johnson, W. K., "Process Kinetics for Denitrification," Jour,
     SED, ASCE pp 623^634  August, 1972.

56.  "How to Get Low Ammonia Effluent," Water and Sewage Works
     p 92, August 1974.

57.  Duddles, Glenn A., et.al., "Plastic Medium Trickling  Filters
     for Biological Nitrogen Control," JWPCF vol. 46 No. 5
     pp 937-946, May 1974.

58.  Lue-Hing, Cecil, et.al. "Nitrification of a High Ammonia
     Content Sludge Supernatent by use of  Rotating Discs,"
     presented at 29th Annual Purdue Industrial Waste Conference,
     May 1974.

59.  Haug, R. T. and Perry L. McCarty, "Nitrification with the


                              186

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     Submerged Filter" presented at Annual Water Pollution Control
     Federation Conference San Francisco, Ca., October, 1971.

60,  Sutton, Paul M., et.al., "Biological Nitrogen Removal - The
     Efficacy of the Nitrification Step," presented at Annual
     Conference WPCF, Denver, Colorado, October 1974.

61.  Lawrence, Alonzo W and C. G. Brown/ "Biokinetic Approach to
     Optimal Design and Control of Nitrifying Activated Sludge
     Systems "presented at Annual Meeting New York Water Pollution
     Control Association, New York, January 1973.

62.  Baumann, R. E. and J. L, Cleasby, "Design of Filters for
     Advanced waste Treatment" Engineering Research Institute,
     Iowa State University,* Ames, Iowa, October, 1973.

63,  Rice, G. A. and J. L. Cleasby, "Reported Efficiencies for
     Direct Filtration of Plant Effluents/1 Iowa State University,
     Ames, Iowa, March 1974.

64.  Baumann, R. E., "Design of Filters for Advanced Wastewater
     Treatment," Engineering Research Institute, Iowa State
     University Ames, Iowa, June 1973.

65.  "Water and Pollution Control Technology Report" Neptune
     Micro FLOC, Inc., Volume 4, Number 1, September 1970.

66.  Weddle, C, L., et.al., "Studies of Municipal Wastewater
     Renovation for Industrial Water" presented before Annual
     Conference of the Water Pollution Control Federation,
     October, 1971.

67.  "Comprehensive Monthly Report," Dallas Water Utilities
     Department, Water Reclamation Research Center, July 1973.

68.  University Area Joint Authority, operating report of
     October 6, 1971, State College, Pa.

69.  Metropolitan Sewer District, operating report of October,
     1971, Louisville, Kentucky.

70.  "Upgrading Existing Wastewater Treatment Plants11 U. S.
     Environmental Protection Agency Technology Transfer
     Process Design Manual, October 1974.

71.  Beckman, W. J., et al, "Combined Carbon Oxidation -
     Nitrification," Journal WPCF, p 1916-1931 volume 44,
     October 1972.

72.  Drews, R.J. L.C. and A.M. Greef, "Nitrogen Elimination
     by Rapid Alternation of Aerobic/Anoxic Conditions in
     orbal Activated Sludge Plants," Water Research
     Volume 7, Pergaman Press, 1973.

73.  Lynam, B.T. and V.W. Bacon, "Filtration and Microstraining


                             187

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     of Secondary Effluent," from Water Quality Improvement
	by Physical and Chemical Processes University of Texas
     Press, 1970.

74.  Gulp, Gordon L., "Physical Chemical Techniques
     for Nitrogen Removal" prepared for EPA Technology
     Transfer Seminar, March, 1974.

75.  "Ammonia Removal from Agricultural Runoff and
     Secondary Effluent by Selected Ion Exchange,"
     U. S. Department of the Interior, I^PCA,
     Cincinnati, Ohio, March, 1969.

76.  "Wastewater Filtration Design Considerations," U, S.
     Environmental Protection Agency, Technology Transfer,
     Washington, D. C., July 1974.

77.  "Upgrading Existing Lagoons," U. S. Environmental
     Protection Agency, NERC, Cincinnati, Ohio, October,
     1973.

78.  Reynolds, J. H., et. al., "Single and Multi-stage
     Intermittent Sand Filtration to upgrade Lagoon
     Effluents" Utah State University, Logan, Utah,
     November, 1974.

79,  Middlebrooks, E. J., et. al., "Evaluation of Techniques
     for Alage Removal from Wastewater Stabilization Ponds,"
     Utah Water Research Laboratory, Utah State University,
     Logan, Utah January, 1974.

80.  Clark, S. E., et. al,, "Alaska sewage Lagoons," Federal
     Water Quality Administration, Alaska Water Laboratory,
     College, Alaska, 1970.

81.  "Lagoon Performance and the State of Lagoon Technology"
     U. S. Environmental Protection Agency, Office of Research
     and Monitoring, June, 1973.

82.  "Supplementary Aeration of Lagoons in Rigorous Climate
     Areas," U. S. Environmental  Protection Agency,
     October, 1971,

83.  "Biological Waste Treatment  in the Far North," Federal
     Water Quality Administration, Alaska Water Laboratory,
     June 1970.
                              188

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                           SECTION XIV

                            GLOSSARY
"Act":
1972.
The Federal Water Pollution  Control  Act  Amendments  of
Activated  Sludge  Process:   Aerated basin in which waste waters
are mixed with recycled biplogically active sludge for periods of
about 6 hours.

Aerated:  The introduction and intimate contacting of air  and  a
liquid  by  mechanical  means  such  as  stirring,  spraying,  or
bubbling.
Aerobic:  Living or occurring only in the presence
or molecular oxygen.
                                            of  dissolved
Algae:   Major  group  of  lower plants, single and multi-celled,
usually aquatic and capable of synthesizing  their  foodstuff  by
photosynthe sis.

Ammonia  Stripping:   Ammonia  removal  from a liquid, usually by
intimate contacting with an ammonia-free gas such as air.

Anaerobic:  Living or active only in the absence of free oxygen.

Bacteria:  Primitive plants, generally  free  of  pigment,  which
reproduce  by  dividing in one, two, or three plants.  They occur
as single  cells,  chains,  filaments,  well-oriented  groups  or
amorphous masses.

Biodegradable:  The condition of a substance which indicates that
the  energy content of the substance can be lowered by tlie action
of biological agents  (bacteria) through chemical  reactions  that
simplify the molecular structure of the substance.

Biological  Oxidation:  The process whereby, through the activity
of living organisms in an aerobic environment, organic matter  is
converted to more biologically stable matter.

Biological  Stabilization:   Reduction in the net energy level of
organic  matter  as  a  result  of  the  metabolic  activity   of
organisms, so that further biodegradation is very slow.

Biological  Treatment:  Organic waste treatment in which bacteria
and/or  biochemical  action  are  intensified  under   controlled
conditions.

Blinding:   The  plugging  of the openings in the screen qr metal
fabric that is part of a prqcess screening device.
Slowdown:  A discharge of water from a system to prevent a
up of dissolved solids, e.g., in a boiler.
                                                    build
                               189

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BODji:   A  measure of the oxygen consumption by aerobic organisms
over a five day test period at 20°C.  It is an  indirect  measure
of  the concentration of biologically degradable material present
in organic wastes contained in a water stream.

Broiler:  A young chicken typically eight to nine weeks old  with
an average market live weight of 1,7* fcg (3.8 Ib) ,
By-Products:   The  feathers, offalf and blood that are recovered
and used as rendering raw materials.

Category and Subcategory:  Divisions  of  a  particular  industry
which  possess  different  traits  £hat  affect  raw  waste water
quality,

Chemical  Precipitation:   A  waste  treatment  process   whereby
substances  dissolved  in  the  waste  water  stream are rendered
insoluble and form a solid phase  that  settles  out  or  can  be
removed by flotation techniques.

Chicken:   Often  a  catch-all  classification  of both young and
mature fowl including domestic fowl, broilers, fryers,  roasters,
and  stewing  hens; in this report, a specific subcategory of the
industry excluding mature chickens or fowl,

Chilling:  In the poultry processing industry, chilling refers to
the processing  of  rapid  cooling  of  carcasses  in  ice  water
following the evisceration process.

CIP System:  "Clean-in-place" equipment and plant cleaning system
using  a  spray-oh detergent that remains in place wherever it is
sprayed until it is rinsed off.

Clarification:  Process of removing undissolved materials from  a
liquid,  specifically,  removal  of  solids either by settling or
filtration.

Clarifier:  A. settling basin  for  separating  settleable  solids
from waste waters.

cm:  Centimeter.

Coagulant:   A  material,  which  when  added to liquid wastes or
water, creates a reaction which forms  insoluble  floe  particles
that  absorb and precipitate colloidal and suspended solids.  The
floe particles can be removed by sedimentation.  Among  the  most
common  chemical  coagulants  used in sewage treatment are ferric
sulfate and alum.

Coanda Phenomenon:  Tendency of a flowing fluid to  adhere  to  a
curved surface.

COD-Chemical   Oxygen   Demand:    An  indirect  measure  of  the
biochemical load imposed on the oxygen  resource  of  a  body  of


                               190

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water  when  organic  wastes  are  introduced  into the water.   A
chemical test is used to determine COD of waste water.

Comminuted Products:  Processed meat products prepared with  meat
and  fat  pieces  that have been reduced to minute particle size;
e.g., luncheon meats.

Condoiisables:  Rendering vapors capable of being condensed.

Condensate;  The liquid produced by condensing rendering  cooking
vapors.

Contamination:   A  general term signifying the introduction into
water of microorganisms, chemical, organic or  inorganic  wastes,
or sewage, which renders the water unfit for its intended use.

Curing:    A  process,  method,  or  treatment  involving  aging,
seasoning,  washing,  drying,  injecting,  heating,  smoking,  or
otherwise  treating  a  product,  especially  meat,  to preserve,
perfect, or ready it for use.

Defeathering:  Process of removing feathers from birds.

Denitrification:    The   process   involving   the   facultative
conversion  by  anaerobic  bacteria of nitrates into nitrogen and
nitrogen oxides.

Digestion:   Though  "aerobic"  digestion  is  used,   the   term
digestion  commonly  refers to the anaerobic breakdown of organic
matter in water solution  or  suspension  into  simpler  or  more
biologically  stable  compounds  or  both.  Organic matter may be
decomposed to soluble organic acids or alcohols, and subsequently
converted to such gases as methane and carbon dioxide.   Complete
destruction  of organic solid inaterials by bacterial action alone
is never accomplished.

Dissolved Air Flotation:  A process involving the compression  of
air  and  liquid,  mixing  to super-saturation, and releasing the
pressure to generate large numbers of minute air bubbles.  As the
bubbles rise to the surface of the water, they  carry  with  them
small  particles  that they contact.  The process is particularly
effective for grease removal.

Dissolved Oxygen:  The oxygen  dissolved  in  sewage,  water,  or
other  liquid,  usually  expressed  as milligrams per liter or as
percent of saturation.

Duck:  A type of domestic water fowl with a typical  market  live
weight of 1.8 to 3.2 kg  (4 to 7 Ib).

Edible:  Products that can be used for human consvnption.
Effluent:
unit.
Liquid which flows from a containing space or process
                            191

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Microstrainer/Microscreen:   A  mechanical filter consisting of a
cylindrical surface of metal filter fabric with openings of 20-60
micrometers in size.

mm:   Millimeter = 0.001 meter.

Municipal Treatment:  A city- or community-owned waste  treatment
plant for municipal and possibly industrial waste treatment,

New  Source:   Any building, structure, facility, or installation
from which there is or may be a discharge of pollutants and whose
construction is commenced after the publication of  the  proposed
regulations,

titrate.  Nitrite:   Chemical  compounds  that  include  the N
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Polishing:  Final treatment stage before discharge of effluent to
a water course.  Carried out in  a  shallow,  aerobic  laqoon  or
pond,  mainly  to  remove  tine suspended solids that settle very
slowly.  Some aerobic microbiological activity also occurs.

Pollutant:  A substance which taints, fouls, or otherwise renders
impure or unclean the recipient system.

Pollution:  The presence of pollutants in a system sufficient  to
degrade the quality of the system,

Polyelectrolyte  Chemicals:   High  molecular  weight  substances
which dissociate into ions when  in  solution;  the  ions  either
being  bound  to  the  molecular  structure  or  free  to diffuse
throughout the solvent, depending on the sign of the ionic charge
and the type of electrolyte.  They are often used as flocculating
agents  in  waste  water  treatment,  particularly   along   with
dissolved air flotation.

Ponding:  A waste treatment technique involving the actual holdup
of all waste waters in a confined space,

ppm:   Parts  per  million,  a  measure  of concentration usually
expressed currently as mg/1,

Pretreatment:  Waste water treatment located on  the  plant  site
and upstream from the discharge to a municipal treatment system.

Primary   (In-Plant)  Waste Treatment:  In-plant materials (grease
and solids) recovery and waste water treatment involving physical
separation and recovery devices such as  catch  basins,  screens,
and dissolved air flotation.

Raw  Waste:   The  waste water effluent from the in-plant primary
waste  treatment system.

Recycle:  The return of a quantity of effluent  from  a  specific
unit   or  process  to the feed stream of that same unit including
the return of treated plant waste water for several plant uses.

Rendering:  Separation of fats and water from  poultry  offal  by
heat   or  physical energy.  "Rendering" operations in the poultry
processing industry  also  include   such  operations  as  feather
hydrolysis and blood processing for  animal  feeds.

Return  on  Assets   (ROA):   A  measure  of potential or realized
profit as a percent of the total assets  (or fixed assets) used to
generate the profit.

Return on investment  (ROI):  A measure of potential  or  realized
profit as a percentage of the investment required co generate the
profit.
                              195

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Reuse:   Referring  to  waste reuse.  The subsequent UP? of water
following an earlier use without restoring  it.  to  the  original
quality.

Riprap:   A  foundation or sustaining wall, usually of stones and
brush, so placed on an embankment or a lagoon to prevent erosion.

RM:  Referring to the raw material used in the rendering process.

Rot a t i ng  B io logic a 1  C on tac tor:   A.   wa ste   treatment   device
involving  closely  spaced  light-weight  disks which are rotated             ( ..
through the waste water allowing aerobic microflora to accumulate
on each disk and thereby  achieving  a  reduction  in  the  waste
content.
                                                                             1
Sand  Filter:   A filter device incorporating a bed of sand that,
depending on design, can be used in biological or advanced  waste
treatment.

Secondary  Treatment:   The waste treatment following primary in^
plant treatment.  Typically involving biological waste  reduction
systems.

Sedimentation  Tank:   A  tank or basin in which a liquid  (water,
sewage, liquid manure) containing settleable suspended solids  ijp
retained  for  a  sufficient time so part of the suspended solids
settle out by gravity.  The time  jjlnterval  that  the  liquid  is
retained  in  the  tank  is called "detention period."  In sewag|e
treatment,  the  detention  period  is  short  enough  to   avoid
putrefaction.

Settling Tank:  Synonymous with "Sedimentation Tank."                         ':

Sewage:   Water  after  it has been fouled by various uses.  From
the standpoint of source it may be a combination of the liquid or
water-carried wastes from  residences,  business  buildings,  and
institutions,   together   with   those   from   industrial   and
agricultural establishments, and with such  groundwater,  surfape
water, and storm water as may be present.

Shock  Load:  A quantity of waste water or pollutant that greatly
exceeds the normal discharged inl^o a  treatment  system,  usually             ^
occurring over a limited period of time.

Skimmings:  Fats and floatable solids recovered from waste waters
by catch basins, skimming tanks, and air flotation devices.                   ^

Sludge:   The accumulated settled solids deposited from sewage or
other wastes, raw or treated, in tanks or basins, and  containing
more or less water to form a semiliquid mass.

Slurry:  A solids-water mixture, with sufficient water content to
impact fluid handling characteristics to the mixture.
                             196

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          Small  Game:   Includes  rabbits,  pheasants, partridge, pigeons,
          squabs and guineas, and is often referred to as other poultry  by
          the industry.

          Stoichoimetric  Amount:   The amount of a substanqe involved in a
          specific chemical reaction, either as a reactant or as a reaction
          product.

          Surface waters:  The waters of the United  States  including  the
          territorial seas.

          Suspended  Solids  (TSS)-.  Solids that either float on the surface
          of, or are  in  suspension,  in  water;  and  whiqh  are  largely
          removable   by   laboratory   filtering   as  in  the  analytical
          determinant of TSS content of waste water.

          Tertiary waste Treatment:  Waste treatment system^ used to  treat
          biological    treatment  effluent;  and  typically  use  physical-
          chemical technologies to effect waste reduction.  Synonymous with
          "Advanced Waste Treatment."

          Total Dissolved Solids  (TDS) :  The solids content of waste  water
          that is soluble and is measured as total solids content minus the
          suspended solids,

          Turkey:   A type of poultry with an average market live weight of
          about 8.2 kg  (19 Ib).  Market live weight varies,  however,  from
          about  3.6  kg   (8 Ib) for fryer-roaster  (young) turkeys to about
          9,0 kg  (20 Ib) for mature turkeys.
          Viscera:   All   internal   organs   of
          evisceration.
poultry   removed   during
           Zero   Discharge:    The   discharge   of   no pollutants  in  the  waste
           water  stream  of  a plant that  is  discharging  into a.  receiving body
           of water.
Htf
                                         197

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VO
00
                                              TABLE

                                          METRIC TABLE

                                         CONVERSION TABLE

             MULTIPLY  (ENGLISH UNITS)                    by                TO OBTAIN (METRIC UNITS)

                  ENGLISH UNIT      ABBREVIATION    CONVERSION   ABBREVIATION   METRIC UNIT
 acre                    ac
 acre - feet             ac ft
 British Thermal
   Unit                  BTU
 British Thermal
   Unit/pound            BTU/lb
 cubic feet/minute       cfm
 cubic feet/second       cfs
 cubic feet              cu ft
 cubic feet              cu ft
 cubic inches            cu in
-degree.Fahrenheit       °F
 feet                    ft
 gallon                  gal
 galIon/minute           gpm
 horsepower              hp
 inches                  in
 inches of mercury       in Hg
 pounds                  Ib
 million gallons/day     mgd
 mile                    mi
 pound/square
   Inch (gauge)           psig
 square feet             sq ft
 square inches           sq in
 ton (short)             ton
 yard                    yd
                                                      0.405
                                                   1233.5

                                                      0.252
ha
cu m

kg cal
0.555
0.028
1.7
0.028
28.32
16.39
0.555(°F-32)*
0730*8
3,785
0.0631
0.7457
2.54
0.03342
0.454
3,785
1.609
kg cal/kg
cu m/min
cu m/min
cu m
1
cu cm
°C
m
1
I/sec
kw
cm
atm
kg
cu m/day
km
                                               (0.06805 psig +1)*  atm
                                                      0.0929       sq m
                                                      6.452        sq cm
                                                      0.907        kkg
                                                      0.9144       m
 hectares
 cubic meters

 kilogram - calories

 kilogram calories/kilogram
 cubic meters/minute
 cubic meters/minute
 cubic meters
 liters
 cubic centimeters
 degree Centigrade
"meters
 liters
 liters/second
 killowatts
 centimeters
 atmospheres
 kilograms
 cubic meters/day
 kilometer

 atmosyherss (absolute)
 square maters
 square ceniimetars
 metric ton (1000 kilograms)
 meter
               Actual  conversion,  not a multiplier
                                                                                    1      *

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