EPA R2-72-018
NOVEMBER 1972 Environmental Protection Technology Series
PROCEEDINGS THIRD
NATIONAL SYMPOSIUM
ON FOOD PROCESSING WASTES
National Environmental Research Center
CKiice of Research and Monitoring
U.S. Environmental Protection Agency
Corvallis, Oregon 97330
-------
RESEARCH REPORTING SERIES
Research reports of the Office of Research and
Monitoring, Environmental Protection Agency, have
been grouped into five series. These five broad
categories were"established to facilitate further
development and application of environmental
technology. Elimination of traditional grouping
was consciously planned to foster technology
transfer and a maximum interface in related
fields. The five series ares
1. Environmental Health Effects Research
2. Environmental Protection Technology
3. Ecological Research
H. Environmental Monitoring
5. Socioeconomic Environmental Studies
This report has been assigned to the ENVIRONMENTAL
PROTECTION TECHNOLOGY series. This series
describes research performed to develop and
demonstrate instrumentation, equipment and
methodology to repair or prevent environmental
degradation from point and non-point sources of
pollution. This work provides the new or improved
technology required for the control and treatment
of pollution sources to meet environmental quality
standards..
For sale by the Superintendent of Documents, U.S. Government Printing Office, Washington, D.C. 30102 - Price $5.25
-------
EPA-R2-72-018
November 1972
PROCEEDINGS THIRD NATIONAL SYMPOSIUM
ON FOOD PROCESSING WASTES
March 28-30, 1972
New Orleans, Louisiana
National Waste Treatment Research Program
Pacific Northwest Water Laboratory
200 S.W. 35th Street
Corvallis, Oregon 97330
Program Element No. 1B2037
NATIONAL ENVIRONMENTAL RESEARCH CENTER
OFFICE OF RESEARCH & MONITORING
U.S. ENVIRONMENTAL PROTECTION AGENCY
CORVALLIS, OREGON 97330
-------
FOREWORD
This Third National Symposium on Food Processing Wastes was held
concurrently with the American Society of Mechanical Engineer's
Process Industries Division meeting on Waste Water Reuse in Industry.
Early in the planning stages it was learned that both ASME and
EPA were planning meetings in New Orleans at approximately the
same time with the same general theme, and so it was decided
to hold a concurrent meeting in the interest of efficiency.
The National Symposium on food processing waste was again co-
sponsored this year with the National Canners Association. Much
of the success of the meeting and the interest and participation
by industry is attributed to the efforts of NCA in publicizing
and encouraging attendance at the meeting.
The technical papers presented at the sessions covered a wide
range of reseach and demonstration projects on new methods of
waste treatment and showed an increasing emphasis on in-plant
process changes to reduce or eliminate liquid waste flows. Several
projects concerned with treatment to permit recycling of wastes
were presented.
-ill
-------
CONTENTS
REPORT ON FIRST COMMERCIAL EVALUATION OF DRY CAUSTIC PEELING
OF CLINGSTONE PEACHES 1
Herbert E. Stone
REDUCED WASTE GENERATION BY ALTERNATE VEGETABLE BLANCHING
SYSTEMS 25
Dr. Jack W. Rails, Harry J. Maagdenberg, Nabil L. Yacoub,
and Walter A. Mercer
A FIELD STUDY ON THE APPLICATION OF INDIVIDUAL QUICK
BLANCHING 71
Daryl B. Lund
WASTE CONTROL IN THE PROCESSING OF SWEET POTATOES 85
N. V. Colston and C. Smallwood, Jr.
RBC TREATMENT OF SIMULATED POTATO PROCESSING WASTES 99
M. W. Cochrane and K. A. Dostal
TREATMENT OF SOY WHEY BY MEMBRANE PROCESSES .......... 117
R. L. Goldsmith, M. M. Stawairski, E. T. Wilhelm, and
G. Keeler
FULL-SCALE ANAEROBIC TRICKLING FILTER EVALUATION . . 151
Dennis W. Taylor
ICE CREAM WASTEWATER CHARACTERIZATION AND TREATABILITY .... 163
E. F. Dul
THE USE OF CHEMICAL TREATMENT AND AIR FLOTATION FOR THE
CLARIFICATION OF FISH PROCESSING PLANT WASTE WATER
F. G. Claggett
-------
TERTIARY TREATMENT OF COMBINED DOMESTIC AND INDUSTRIAL
WASTES 201
Harold W. Thompson and Kenneth A. Dostal
OCEAN ASSIMILATION OF FOOD RESIDUALS 217
Walter W. Rose, Allen M. Kaysuyama, and Richard W. Sternberg
PROCESS DESIGN FOR TREATMENT OF CORN WET MILLING WASTES .... 277
H. 0. Bensing and D. R. Brown
SEPARATION, DEWATERING AND DISPOSAL OF SUGARBEET TRANSPORT
WATER SOLIDS 293
I. V. Fordyce and A. M. Cooley
WINERY WASTEWATER TREATMENT 311
Edwin Haynes, George Stevens, and Paul Russell, Jr.
TREATMENT OF CHEESE PROCESSING WASTEWATERS IN AERATED
LAGOONS 323
William C. Boyle and Lawrence B. Polkowski
CHARACTERIZATION AND TREATMENT OF BREWERY WASTES 371
Henry G. Schwartz, Jr. and Richard H. Jones
CATTLE PAUNCH CONTENTS AS FISH FEED SUPPLEMENT: FEASIBILITY
STUDIES 401
S. C. Yin and Jack L. Witherow
CHARACTERIZATION OF FRUIT AND VEGETABLE PROCESSING
WASTEWATERS 409
M. R. Soderquist, G. I. Blanton, Jr. and D. W. Taylor
vi
-------
PROGRESS REPORT: SEAFOODS PROCESSING WASTEWATER
CHARACTERIZATION 437
M. R. Soderquist, G. I. Blanton, Jr., J. E. Borden and
K. S. Hilderbrand
SUMMARY: FOOD WASTE RESEARCH—WHERE DO WE GO FROM HERE? ... 481
Dale A. Carlson
REGISTRATION LIST 489
vii
-------
REPORT OK FIRST COMMERCIAL EVALUATION OF
DRY CAUSTIC PEELING OF CLINGSTONE PEACHES (2)
by
Herbert E. Stone
INTRODUCTION
Del Monte Corporation, in cooperation with the Environmental Protection
Agency under Grant Project No. 12060 HFY, investigated the commercial
feasibility of using the dry caustic peeling process to remove chemically
softened peach peel and to retain it in a manner which would allow its
disposal as a solid material. This process uses the principle of
gently wiping the major portion of peel from the peach halves with a
series of uniquely designed soft rubber discs which rotate and tumble
the fruit. New equipment, specifically designed for this purpose,
facilitates the peeling. A series of fresh water sprays — applying a
minimum amount of water — removes any residual peel remaining after the
wiping action.
Clingstone peach is a major crop with an annual production exceeding
30 million cases. Being a seasonal fruit, it cannot be stored for any
length of time. The production period is therefore relatively short, ranging
from only a few weeks, in some areas, to a maximum of three months.
The most common commercial peeling process for cling peaches utilizes
a dilute sodium hydroxide (caustic) solution to soften the peel. This
is followed by large quantities of fresh, potable water applied under
high pressure to dislodge and remove the peel and caustic residues. The
effluent from this operation frequently contains relatively high amounts
of dissolved and undissolved organic materials which do not lend themselves
to mechanical removal. Consequently, these wastes comprise a portion of
the liquid effluent from the plant.
Disposal of this effluent with the resultant organic and hydraulic loads
which may be imposed on municipal or privately owned waste treatment
systems has frequently been a serious concern to communities in plant
locations, as well as to regulatory agencies.
(l)Manager, Environmental Protection, Del Monte Corporation,
San Francisco, California
(2)This investigation was supported by funds from the Environmental
Protection Agency Water Quality Office under Grant No. 12060HFY.
-------
In response to this concern, the food processing industry has completed a
number of research projects whose prime goals have been determining means
for reducing:
l) the generation of oxygen demanding substances (BOD, COD, etc.)
which are a natural component of the food; and,
2) the use of fresh water in plant or processing areas where product
quality and sanitation requirements would not be adversely affected.
One such project was carried out in 1970 under EPA (formerly'Federal Water
Quality Administration) Research and Development Grant No. 12060 FQE
entitled "Dry Caustic Peeling of Tree Fruit for Liquid Waste Reductions".
(Reference #l) Under this project, the National Canners Association
Western Research Laboratory in Berkeley, California, with the assistance
of the Western Utilization Research Laboratory of USDA in Albany, California,
demonstrated the feasibility for removing caustic softened peach peel with
the aid of rapidly rotating, soft rubber discs, retaining the solid peel
separate from the liquid waste stream and removing the small amounts of
residual peel and chemical residue with markedly reduced volumes of fresh
water.
On the basis of these pilot scale results, Del Monte Corporation offered
a proposal to the Environmental Protection Agency to design, construct and
permanently install equipment which would afford a commercial demonstration
of the feasibility for peeling cling peaches, removing and retaining the
peel as a solid waste and significantly reducing the volume of fresh
water normally used during this phase of the preparation of peaches for
canning.
EPA Research and Development Grant No. 12060 HFY was awarded on April 1,
1971 for the purpose of partially supporting the implementation of this
proposal. Del Monte Corporation Plant No. 3, located in San Jose, California,
was selected as the site for this demonstration installation.
Commercial size equipment was designed by Del Monte engineers and constructed
in a company-owned machine shop and on the site by plant personnel. Details
of the design and installation are appended to the final report which will
be available shortly from EPA. (Reference #6)
Installation of the experimental peeler was completed during the early
summer of 1971. A brief test period under production conditions indicated
a need for adjustments and minor modifications of the peeler and a conveyor
belt. Continuous, three-shift operation of the experimental peeler was
initiated on August 10, 1971. The evaluation continued through September 17,
the close of the 1971 cling peach canning season.
The commercial size equipment was patterned after the NCA-USDA model and
was scaled in size to peel 10-12 tons per hour of pitted cling peach halves
equal to approximately 25$ of the total plant production.
-------
A sub-project in the evaluation of the new peeling process for cling peaches
was the biological treatment of water used as a final rinse after peel
removal. Concentrated waste water was segregated from all other waste
flows and piped directly to an existing high rate trickling filter biological
treatment system which had been used in previous studies and is described in
greater detail in other reports. (References (2)(3)) Work under this phase
of Project 12060 HFY was supervised and conducted by personnel from the
National Canners Association Western Laboratories in Berkeley, California.
CONVENTIONAL PEELING
In the conventional peeling method, (Figure No. l) pitted peaches are
turned so that the pit cavity is facing downward (termed "cup down") on a
LaPorte metal (link chain) conveyor belt immediately prior to entering a
partitioned tank. In the first section of the tank, peach skins are sprayed
with a dilute solution of hot sodium hydroxide (caustic). The conveyor
carries the fruit through the second steam heated holding section where
chemical action on the skins is completed. In the last section, the fruit
is carried under a series of high pressure water sprays where peel and
caustic residue are removed and flushed into floor drains for disposal.
In the operation at Del Monte's Plant No. 3> as many as 20 banks of sprays
may be used to complete the peeling. However, only the final six spray
headers apply fresh water with the remainder divided into groups of sprays
using recycled rinse water in a countercurrent manner.
Control of chemical peeling is achieved by adjustments of the sodium
hydroxide concentration, temperature of the solution and speed of the
conveyor to allow for reaction time of the hydroxide solution on the skin.
If necessary, a food grade wetting agent may occasionally be added to the
caustic solution to facilitate removal of tenaciously adhering peels on
some varieties of fruit.
Following the final series of fresh water sprays, the peach halves are again
inverted so that the pit cavity is facing up as the fruit is conveyed past
another visual inspection station where defects or other lower quality
peaches are removed for trimming, diversion to an alternate style of product
or discarded. Defects include pit fragments, peel residues, blemishes,
imperfect halves, green fruit, etc.
DRY CAUSTIC PEELING
Peach halves peeled by the experimental dry caustic method (Figure 2) are
subjected to the identical sodium hydroxide solution concentration,
temperature and holding period as the conventional method described above.
However, prior to rinsing with water, peach halves are diverted from the
LaPorte conveyor onto a cross conveyor rubber belt which provides distribu-
tion over the full width of the dry caustic peeling unit, described in
greater detail below. From the peeling unit, peaches slide down a
short chute into a tank of water from where they are elevated by a link
chain slat conveyor to another conveyor for return to the inspection
belts, described previously.
-------
PITTED
FRUIT
(cup-down)
FRESH
•WATER
METER
-SODIUM
HYDROXIDE
SOLUTION
SODIUM HYDROXIDE
PEELER TANK
CUP-UP SHAKER
INSPECTION BELT
RINSE WATER TO
MUNICIPAL SEWER
SAMPLER-
SAMPLE BOTTLE
(r»frlg«ralod)
Figure 1. Schematic-conventional liquid caustic peeler
-------
r-TROUGHED
1 CONVEYOR
SODIUM
HYDROXIDE
SOLUTION
FRESH
WATER
METER
DRY PEELER
DISC SECTION
(cup- up)
APPLICATION
SECTION
HOLDING
SECTION
PITTED
FRUIT
(cup-down)
FRESH WATER
SPRAYS
FLIGHT
ELEVATOR
i— RINSE TANK
SODIUM HYDROXIDE
PEELER TANK
PEEL SOLIDS
TO WASTE
HOPPER
TO CUP-UP
SHAKER AND
INSPECTION BELT
RINSE WATER
TO BIOLOGICAL
TREATMENT SYSTEM
TIMER
SAMPLE BOTTLE
(rafrigeratad)
Figure 2. Schematic-dry caustic peeler
-------
Once past this inspection station, no attempt is made to keep "dry" and
conventionally peeled peaches separate or to differentiate in any subsequent
grading, preparation, canning or processing operation.
DEMONSTRATION EQUIPMENT
The dry caustic peeling unit consists of a frame — six feet wide by ten
feet long — mounted on adjustable legs. A series of 39 stainless steel
shafts are mounted across the six-foot dimension. Specially designed,
soft rubber discs (food grade rubber) are mounted on each shaft.- A chain
drive from a 7-1/2 H.P. vari-speed U. S. Motor to sprockets at the end of
each shaft provide positive rotation of the discs. The rotating action
cleans the peach halves and transports them across the top of the peeler.
Peeling is achieved by the gentle abrasion of discs rotating at a speed
of approximately 325 rpm. Discs are of two types. The larger U-l/4 inch
diameter size incorporates a flexible flanged edge -which gently removes
the softened peel on peaches traveling in a single layer on the tops of
the discs. The smaller 2-3/^ inch diameter stub discs are mounted on
specific shafts and strategically placed to invert peach halves which may
turn over into a "cup down" position as a result of the tumbling action.
It is, of course, necessary to expose the peel portion of the peach to the
abrasive action of the discs.
Figure No. 3 is an engineering diagram of the two types of discs. More
complete details regarding configuration, dimensions and placement of
discs may be found in the engineering drawings appended to the EPA report
on Project 12060 HEY (Reference 6).
Discs and spacer sections between discs are cast as one piece in the mold.
A projection or "key" in the center hole is also an integral portion of
each disc. The "key" fits into a slot on the shaft, thereby achieving
positive drive of the disc. This contrasts with the previous year's
pilot model which used plastic spacers between the discs and depended upon
friction to drive the discs.
As noted above, movement of the peach halves is achieved by discs rotating
in the same direction as the flow of fruit. Duration of time on the
peeler unit is controlled by adjustment of the height of the discharge
end over the feed end. The discs, in effect, are pushing the peach halves
up a slight incline. A 17-18 inch rise over the ten foot length from
feed to discharge end of the peeler was found optimum for the varieties
of peaches processed by the plant during the 1971 canning season.
Peel and caustic residues fall between the rotating rubber discs into "a
conically shaped tank from where they are pimped through a separate
V diameter pipe into a large hopper in the plant yard. (The waste from
this hopper is combined with solid wastes from other fruit preparation
operations and is hauled by truck to an approved land disposal site.)
-------
44-
R. (typical)
1
\\
• D.
."D.
J
^
^
—
'
I
c
*>
9C
qc
1
^
7
i
i
>a
X
2
^
x^
1
.— 1." KEYWAY
J 1
I.OOO"D,
I,005"D.
1 I
CROSS - SECTION DETAIL
STUB DISC
FLANGE DISC
Materlali Black Rubber - 50 Durometer-Food Grade
Figure 3. Rubber Disc Detail
-------
The chemically softened peel material, as it is removed from the peach
halves, is a viscous slurry or semi-solid which can be pumped easily by
commercially available conventional cement type pumps. In this project,
the primary collection tank was drained by manually starting the pump
2-3 times per hour. Each draining represents approximately 60 cubic feet
of peach peel slurry.
Three (3) manifolds of fresh water sprays, mounted above the link chain
elevator conveyor, remove peel and caustic residues and provide the only
fresh water rinsing necessary on the "dry" peeled fruit. These sprays
also serve as make-up water for the tank into which the fruit slides
following the peeler section. Four (If) spray nozzles, each nozzle
delivering approximately one gallon per minute of fresh water, are mounted
on each manifold and positioned to achieve full coverage of the elevator
conveyor width. An automatic sensing device maintains the proper level of
water in the tank following the peeler. Rinse water from this tank is
piped to the biological treatment system being tested by NCA personnel as
a sub-project of the peeling evaluation.
ANALYTICAL PROGRAM
An extensive analytical program was conducted to evaluate the effectiveness
of the dry caustic peeler for removing the peel and retaining the solid
material as a separate entity. Characteristics of the waste rinse waters
from the "dry" method were compared with those from conventional peeling
methods. Figure No. 4 is a schematic of the sampling points for these
parameters. Table I lists analyses conducted in the Del Monte Research
Center and the NCA Laboratory and the schedule for each. The characteristics
of peel and rinse water are those deemed most significant.
As indicated in the schedule, rinse water characteristics were determined
on both 2U-hour composite samples collected daily and on a series of
hourly grab samples collected on two operating days each week during the
project period. The schedule was adjusted to allow for initiation and
completion of laboratory analyses during the normal work week insofar as
possible.
Automatic sampling devices, installed on rinse water discharge lines
from both peelers, were activated by timers which opened a valve allowing
air to "push" a measured quantity of rinse water from each sampling station
through plastic tubing into individual plastic bottles inside a conventional
household style refrigerator, located adjacent to the dry caustic peeling
unit. An eight-ounce sample, drawn once per hour, was selected as the
quantity and frequency of sub-sample for each composite. The reasonably
uniform volume of water used in this operation and the similarly uniform
flow of peaches did not require more frequent sampling or necessitate'
attempts to catch subtle variations. Approximately 2-1/2 gallons of composite
sample were collected daily from each line. The composite bottle was shaken
thoroughly before transferring approximately one gallon to another clean
plastic bottle for transport to the Del Monte laboratory. The larger
composite sample bottles were then drained, rinsed several times with
fresh water, drained again and returned to the refrigerator for collection
of the next 2l*-hour composite sample.
8
-------
•DRY PEELER DISC
SECTION
RINSE TANK
TRICKLING
FILTER
OVERFLOW -*
TO SEWER
-VALVE
FLOW METER
-PUMP
\
VATER -_
SUMP — -^"^
J
i
1
SPRAY RINSE SECTION
FLOW METER
WASTE WATER
STREAM
CONVENTIONAL LIQUID CAUSTIC
PEELER
IDENTIFICATION OF SAMPLING POINTS:
I, Rinse water from conventional commercial peeler
2, Rinse water from experimental dry caustic peeler
3. Peel slurry from experimental dry caustic peeler
4. Influent to trickling filter
5,6 v 7 Intermediate sampjing ports in trickling
filter (no samples collected)
8. Final effluent from trickling filter
DRY CAUSTIC PEELER
Figure 4. Schematic diagram of sampling points
-------
TABLE I - ANALYTICAL PROGRAM
EPA Project - 12060 HFY
Chemical Analysis Required/Sampling Station
Analyses
BOD5 (Total)
BOD5 (Soluble)
COD (Total)
COD (Soluble)
Total Solids
Suspended Solids
Volatile Suspended
Solids
Kjeldahl Nitrogen
Nitrite - Nitrogen
Nitrate - Nitrogen
Total Phosphate
Ortho Phosphate
Alkalinity (Total)
PH
Dissolved Oxygen
Temp. (°C)
Sampling Sta
la
2hC
2*4C
2te
2*4C
2l£
2kC
2kC
G
G
lb
G
G
G
G
2a
2iK3
2kC
2l4C
2ilC
2^C
2»4C
2te
2l4C
2l4C
2l
-------
All samples analyzed at the Del Monte laboratory were on fresh material
which had been refrigerated for 2h hours or less. Samples were stored in
an insulated container during the approximately one hour automobile drive
from plant site refrigerator to Research Center laboratory bench.
Peel loss on the fruit for both "dry" and conventional peeling methods was
determined by comparing weights for a random selection of 100 peach halves,
before exposure to the sodium hydroxide solution, and another 100 randomly
selected halves after peeling and rinsing. Peach halves from each peeling
method were weighed by trained plant personnel, approximately every half
hour throughout the operating day during the duration of the 'demonstration
project.
For clarification, it should be noted that the plant has two completely
separate, but identical, conventional peach peelers. During this project,
one peeler was used as the "control" for evaluation of conventional rinse
water characteristics, water volume measurements and peel loss determinations.
Discharge of rinse water from this peeler was mixed with other liquid waste
streams from the plant.
A portion of the plant's second peeler was used for this demonstration
project and only those peaches and rinse waters which were associated with
the experimental unit are included in the data and discussion. Approximately
25$ of the plant production (10-12 tons per hour) was peeled by the dry
caustic method.
With the exception noted below, all analytical procedures were in accordance
with those listed in "Methods for Chemical Analysis of Water and Wastes -
1971 Edition" as prepared by the Water Quality Office of EPA. The BOD
procedure as outlined in "Standard Methods for the Examination of Water
and Wastewater" - 13th Edition, was followed.
Interference of natural pectin in the fruit prevented use of the conven-
tional methods for separating soluble and suspended or colloidal fractions
of matter in the wastewater samples. Consequently, pretreatment of the
samples was deemed necessary prior to determining soluble BOD and soluble
COD. A series of experiments developed the following procedure:
Wastewater samples were filtered through diatomaceous earth, followed
by filtration through Whatman No. k2 filter paper and ultimately,
centrifuging at 2,000 rpm for 20 minutes. The resultant supernatant
was reasonably clear and considered suitable for soluble BOD and
soluble COD determinations.
Composite samples for analysis of peel characteristics were made by
combining hourly collections of a uniform quantity of peel slurry into a
single one gallon container. This container was held inside a refrigerator
until transfer to the Del Monte laboratory the following morning, along
with composite and hourly samples of rinse water. (There was, of course,
no comparable solid waste sample from the conventional peeling method, as
in the latter instance, all peel is flushed into the liquid stream from
where it cannot be physically separated.)
11
-------
Tables II, III & IV summarize results of composite analyses. Results on
the series of hourly grab samples may be found in the EPA report on the
project. They confirm the composite sample data. (Reference 6)
The sub-project evaluating potential benefits of biological treatment of
the rinse water from the dry caustic unit used concentrated waste water
segregated from all other liquid streams and piped directly to the treat-
ment system. A full description of the treatment procedure may be found
in the EPA report on this project. Briefly, the system that treated the
rinse water was an existing high rate trickling filter which had been
used in previous studies and is described in greater detail in other
reports (References 2 & 3). A schematic diagram of the system is shown
in Figure 5.
To provide for a natural up-draft of air through the treatment column,
air ports were installed around the base of the tank. Four inch pipe
sections were welded around the tank space at 20 degree intervals, making
a total of 18 air ports.
The polyvinyl chloride plastic used in the trickling filter is known as
Surfpac, a registered trade name of the Dow Chemical Company.
Modules of 19x21x39 inches, each with 27 square feet of surface area per
cubic foot and a volumetric void ratio of 0.9^- were welded in a honeycomb
pattern.
A composite 2U-hour sample of the effluent from the trickling filter was
collected each day. Two hour grab samples of the influent were also taken
each day. Both sets of samples were frozen until analyzed at the NCA
laboratory. Procedures for solids, nitrogen and phosphorus determinations
were those listed in "Methods for Chemical Analysis of Water and Wastes -
1971", prepared by the Water Quality Office of EPA. The BOD procedure,
as outlined in "Standard Methods for the Examination of Water and Waste-
water", 13 Edition, 1971? was followed. The Jeris method was used to
determine COD values. (Reference 5)
Tables VII and VTII summarize analytical data obtained during two
sampling periods.
DISCUSSION
Inspection of the data in Tables II and IU, IV, V, & VI,
supports some of the projections made for this demonstration evaluation
of "dry caustic" peeling of clingstone peaches:
l) Removal of the peel and its segregation as a solid waste reduced
the pounds of waste per ton of fruit that would otherwise be
present in the liquid effluent from the plant.
Table VT summarizes the pH and per cent total solids for 8-hour composite
samples of peel waste collected during the demonstration period.
2) Substantial reductions in water volumes required for this
operation are possible.
12
-------
TABLE II
Analytical Data - 2U-Hour Composite Samples
Dry Caustic Peeling Process - Cling Peach Rinse Water
u>
COD
mg/1
BOD.
BOD/COD
Total
Solids
Suspended
Solids
Volatile
Suspended
Solids
mg/1 I
1A
2A
3A
I*A
5A
6A
7A
8A
9A
10A
HA
12A
13A
ll*A
15A
16A
17A
18A
19A
20A
21A
Average:
1+785
7290
8015
9895
8030
3^35
11,305
5l*10
5350
3725
3200
__
1*300
!*325
1*095
2965
5^90
2670
1*820
5910
6965
5600
2190
3820
5770
6170
3860
2890
8655
__
__
2»*05
2365
__
21*85
2375
2720
—
1*51*5
2150
1*000
—
35^0
3750
0.1*6
0.52
0.72
0.62
0.1*8
0.81*
0.77
__
__
0.65
0.7!*
__
0.58
0.55
0.66
—
0.83
o.8l
0.83
—
0.51
0.66
53**5
7010
8U65
7825
6800
1*205
7160
U320
5180
3930
1*290
__
1*1*70
1*085
3990
3895
-_
__
—
--
—
51*00
1650
2925
3550
3630
1630
2860
21*50
2170
1150
2200
2300
2300
1650
2310
2670
2850
2700
2750
21*30
3^70 95.6
2630 91.2
Total Nitrite Nitrate
N H N
mg/1 mg/1 mg/1
110.7
122.6
156.9
108.6
119.8
86.2
108.6
92.5
118 .1*
110.1*
116,5
106.5
117.0
—
__
< 0.02
—
< 0.02
--
< 0.02
—
< 0.02
"_
__
0.2
< 0.02
--
__
2.8
_«.
0.2
--
< 0.1
--
0.2
1.0
-.
0.8
< 0.1
2170 93.9
25^0 95.1
2590 95.9
2680 9l*.5 113.5 < 0.02 0.7
Total Ortho Alkalinity
P P CaC03
mg/1 mg/1 mg/1
7.9
10.0
15.4 0.8
10.1
5.0 <0.1
2.3
2.2
2.8
12.0
5.2
6.7
1.6
0.3
3.2
3.0
pH
1*70
615
1*50
520
^35
370
595
1*80
605
475
620
540
__
—
•^ *•
4* ™
4.35
4.56
4.55
4.90
5.35
4.94
4.89
5.10
5.85
4.73
4.70
4.88
7.0' 1.6
515
I*.90
-------
TABLE III
Analytical Data - 2k Hour Composite Samples
Conventional Peeling Process - Cling Peach Rinse Water
Sample
Ho.
COD
mg/1
BODc
mg/1
BOP/COD
IB
2B
3B
5B
6B
7B
SB
9B
10B
11B
12B
13B
lUB
15B
16B
17B
18B
19B
20B
21B
Average
1680
1305
—
lM*5
2030
11U5
lUlJ
1180
1335
1295
1650
__
2060
1170
1820
3275
—
1135
905
1100
1U35
1520
860
790
—
930
860
795
1025
—
--
990
1080
__
1255
835
11U5
—
--
830
705
--
1080
9UO
0.51
0.61
—
0.6U
O.U2
0.69
0.72
—
--
O.J6
0.65
--
0.61
0.71
0.63
—
—
0.73
0.78
—
0.75
0.65
2725
2165
—
2600
2525
2000
1910
2275
2225
2160
2680
--
3125
2100
25UO
Ul35
—
—
—
—
—
2510
675
14-50
1250
1020
525
570
1350
250
800
750
200
700
300
710
1000
725
92.2
490 90.7
1260 9^.0
6kO 91.1
620 87.3
790 91.1
Total
' N
ag/1
36. k
25.2
35.7
39.9
35.0
32.2
U7.6
56.0
31.9
29.1
22. U
35.7
Nitrite
N
nw/1
—
< 0.02
< 0.02
< 0.02
< 0.02
< 0.02
< 0.02
< 0.02
Nitrate
N
_.
0.2
0.3
0.3
0.2
0.5
0.1
< 0.1
35.1 < 0.02
0.3
Total Orthp Alkalinity
P P CaCO,
mg/1
6.5
1.9 0-7
3.6 --
O.U 0.2
1.0
2.6 0.6
1.7
5.H 1.8
1.8 <0.i
1.6
0.7 .0.1
1.0 0.5
2.9 0.6
U30
UlO
—
U70
UlO
U05
375
U05
UlO
U60
U90
U80
__
_.
— •
8.91
7.62
5.70
6.85
6.51
7.11
6.92
6.80
8.32
6.UO
6.59
6.21
6.20
6.70
6.00
6.90
-------
TABLE IV
COMPARISON OF WASTE EFFLUENT STRENGTH ANALYTICAL DATA
COD
BODC
Dry Caustic
Conventional
Dry Caustic
Conventional
Suspended Solids
Dry Caustic
Conventional
Total
Dry Caustic
Conventional
Total Nitrogen
Dry Caustic
Conventional
Total Phosphate
Dry Caustic
Conventional
Alkalinity
Dry Caustic
Conventional
Range(ppm)
2670-11,300
910-3275
2150-8650
700-1260
1150-3630
200-1700
1910-UiSP
86.l6-156.91
22.U2- U7.63
2.32-15.39
0.69- 9.25
372-619
37^88
Avg.(ppm)
5600
1520
3750
2^30
780
5^00
2510
110.32
6.98
2.88
U30
Dry Caustic
C on ve nt i onal
lt.35-5.85
5.70-8.90
U.90
6.85
15
-------
FRESH WASTE 8 RECYCLED WASTE
ROTARY
IBUTOR
cr
LOW METER
6" VARIABLE
SPEED PUMP
SAMPLING
PORTS
TREATMENT COLUMN
-AIR PORT
TREATED WASTE
TREATED WASTE
OVERFLOW
BAFFLE-
WET WELL SUMP-
-pH METER
DRY-CAUSTIC RINSE WATER
rFLOW METER
-L_3
FLOW METER
t
L
PHOSPHORIC
ACID
•ANHYDROUS
AMMONIA
Figure 5. High rate trickling filter system
-------
TABLE V
COMPARISON OF WASTE GENERATION*
Water Use
COD
Dry Caustic 90 gal/ton
Conventional 850 gal/ton
Dry Caustic ^.2 Ibs/ton
Conventional 10.8 Ibs/ton
BOD,
Dry Caustic 2.8 Ibs/ton
Conventional 6.7 Ibs/ton
Suspended Solids
Dry Caustic 1.9 Ibs/ton
Conventional 5.6 Ibs/ton
Total Solids
Dry Caustic ^.0 Ibs/ton
Conventional 17.8 Ibs/ton
* Average Strengths,
17
-------
TABLE VI
Analytical Data - 8-Ho-ur Composite Samples
Dry Caustic Peeling Process - Cling Peach Peel Solids
-Sample No. Total Solids (*&) pH
IS
2S 7.1
3S 9.2
4S 7.8
5S 10.1 10.62
6S 10.2 8.73
7S 8.5 10.50
8S 9.6 10.55
9S ~ 9-85
10S 9.0 9.12
IIS 10.5 10.32
12S 10.4 9.00
13S 10.7 9.^5
14S 10.5
15S li.o 9.50
16s 10.9 9.48
17S
IBS 7.4
19S
20S 11.2
21S 11.0
Average: 9.7 9-75
Footnote: * ' Peel solids data for day shift only. Spot checks
during night shift indicated similar results.
18
-------
TABLE VII
SUMMARY OF TRICKLING FILTER MTA
Sampling Period - 8M - 9/9
Parameter
pH
Suspended Solids, ppm
Volatile Suspended Solids, ppm
COD, ppm
BOD, ppm
Nitrogen, Total, ppm
Phosphorus, Total, ppm
Lbs. COD/1000 Ft3/Day
Lbs. BOD/1000 Ft3/Day
Influent
6.2
1990
1920
5580
3^90
3ol
.5.9
363
227
Effluent
.5.8
2^4-0
2360
1*3^0
29^0
^•15
8.0
282
191
TABLE VIII
SUMMARY OF TRICKLING FILTER MTA
Sampling Period - 9/10 - 9/22
Parameter
PH
Suspended Solids, ppm
Volatile Suspended Solids, ppm
COD, ppm
BOD, ppm
Nitrogen, Total, ppm
Phosphorus, Total, ppm
# COD/1000 Ft|/Day
# BOD/1000 Ft^/Day
'Influent
2520
3860
220
15.1
353
251
Effluent
5.3
3100
2960
3750
2760
160
13.9
2Mf
179
19
-------
Fresh water sprays on the demonstration unit applied a seasonal average
of 13 gallons per minute versus approximately 125 gallons per minute for
an equivalent amount of fruit in the conventional peeler. These calculate
to approximately 90 gallons of water per ton of peaches in the dry caustic
peeler and 850 gallons per ton of peaches in the conventional peeler.
3) Slightly lower pH levels for 2U-hour composite samples of rinse
water from the "dry" peeler indicate removal of caustic residue
in the segregated solid peel slurry.
U) Peaches peeled by the "dry" process exhibit slightly greater
than average weight loss than those from the conventional peeling
method (7-8$ vs. 6.6$). However, it is believed the causes for
these differences can be corrected. Specifically, the concen-
tration of sodium hydroxide solution is probably higher than
necessary for the "dry caustic" peeling method and results in
greater softening of the peel and sub-dermal layers than would
be necessary in full commercial development of the method. (The
sodium hydroxide solution concentration could not be decreased,
as 25$ of the plant's non-experimental peach production used this
same spray section and any significant change in concentration
would have resulted in an unsatisfactory peeling under conventional
production methods.)
Another possible factor contributing to the greater peel loss
on the "dry" peeled peaches was the additional handling which
these halves received. The action of the diversion bar, shear-
ing halves off of the LaPorte belt, undoubtedly removed some
flesh from the center portion of the peach. A full-scale
commercial unit with a straight flow of fruit would preferably
not have this diversion and its consequent abrasive action.
5) During the first series of tests in the trickling filter, COD in
the rinse water was reduced 22.2$ and the BOD by 15.8$. During
the second series, in which nitrogen and phosphorus were added,
the COD reduction was 31.0$ and the BOD reduction was 28.5$. In
terms of pounds of COD or BOD removed per 1,000 cubic feet per
day, the filter removed 8l pounds of COD and 36 pounds of BOD when
only nitrogen was added. When nitrogen and phosphorus were added,
the filter removed 109 pounds of COD and ?2 pounds of BOD per
1,000 cubic feet per day.
It would appear that the improved performance by the trickling
filter can be attributed at least in part to the addition of
phosphorus as this was the only major difference during,the two
test runs. The phosphorus content of 5.9 PPm during the first
sampling period is considerably less than the recommended ratio
of 100 parts BOD to 1 part phosphorus. With the addition of
phosphorus, the average concentration of the influent increased
to 15.1 ppm and the data show a corresponding increase in BOD
removal.
20
-------
On the basis of removal, the ratios of BOD removed to phosphorus
are similar. For the first series, the ratio is 100:1.1 and for
the second series, it was 100:1.^. It is speculated that if the
phosphorus content were increased above 15 ppm, an even greater
increase in the BOD removal might be realized.
Tables VII and VIII are a summary of data collected on the
performance of the trickling filter. The summary data is divided
into two parts, the first collected when only nitrogen was
added to the influent and the second part when nitrogen and
phosphorus were added.
Phosphorus contents shown in Tables VII and VIII were determined
on unsettled samples. The results between the influent and
effluent are similar and do not indicate phosphorus uptake by
bacteria as the analysis measures the amounts of total phosphorus
in solution as well as in the bacterial mass.
In general, the pH of the rinse water was less alkaline than
expected. This fact, combined with the high recycle ratio,
lowered the pH below optimum levels for biological treatment
and resulted in removing fewer pounds of BOD than anticipated.
Additional analytical data on daily samples may be found in the
EPA Report on this project. (Reference 6}
CONCLUSIONS
l) EPA Project No. 12060 HFY demonstrated that the gentle abrasion
of rapidly rotating flexible rubber discs can remove major portions
of softened peels on clingstone peaches and yield a canning peach
of satisfactory quality. Additional work appears desirable to
establish the full commercial potential for this method.
2) The project demonstrated that a reduction of almost 90$ °f fresh
water requirements was feasible as a result of the prior removal
of peel and caustic residues by the rotating rubber discs. This
volume can represent 10$ of the total fresh water utilized by
some peach canneries.
3) The removal of peach peel and its segregation as a solid waste
results in a decrease in the pounds per day of organic matter
discharged from the cannery in combination with its liquid effluent.
^) Reduced operating costs may result from use of a "dry caustic"
peeler through lowering the costs of water and the operation
and maintenance of private or municipal waste treatment facilities.
5) The gentle peeling action of the rotating discs appears to be
less abusive to overripe fruit. High pressure rinse water sprays
in conventional peelers can damage soft flesh, thereby reducing
overall commercial acceptability.
21
-------
6) Production limitations on certain aspects of the demonstration
equipment indicate that modifications are desirable before full
commercial potential can be determined.
7) Additional work is needed to fully evaluate the potential for
utilizing a high rate trickling filter in treatment of concentrated
vaste effluents from the peeling of peaches.
22
-------
ACKNOWLEDGEMENTS
Del Monte Corporation acknowledges the pilot plant evaluations of dry
caustic peeling of tree fruits conducted during 1970 by the National
Canners Association Berkeley Laboratory in cooperation with the Western
Utilization Research Laboratory of USDA in Albany, California. These
early efforts and subsequent consultation during the design and develop-
ment phase of commercial equipment contributed substantially to this
demonstration project.
We are further appreciative of the efforts of personnel from the National
Canners Association Berkeley Laboratory for their management of the sub-
project concerned with determining the potential effectivenesss of using
a trickling filter biological system for treating concentrated waste
water from peach preparation.
We are also indebted to Mr. Kenneth A. Dostal and Mr. Harold W. Thompson
in the Pacific Northwest Water Laboratory of the Environmental Protection
Agency for their guidance and numerous helpful suggestions in all phases
of the project.
The following members of the Del Monte Corporation made significant
contributions to the design and development of commercial equipment,
supervision of production, and the obtaining and reporting of results.
Research Department:
Dr. Charles P. Niven, Jr. (Director of Research)
Wayne W. Thornburg
Raymond M. Jadarola Robert B. Devore
Jack G. Allen Jo Ruth Wright
Andrew T. Halt on Paul Reiche, Jr.
Richard J. Maass Demetrios Papakonstantino
Production Management;
William L. Hole Walter C. Bergstrom
Robert E. Crawford Edward E. Garcia
Fred H. Laudenslager Robert M. Jorgensen
Gene R. Zolezzi Richard W. Fish
Engineering Department:
Charles D. Wintermantel
Robert E. McLees
Jack B. Schumate
Favio Franceschi
23
-------
1) Report on EPA Project No. 12060 FQE, "Dry Caustic Peeling of Tree
Fruit to Reduce Liquid Waste Volumes and Strength" by National
Canners Association, Berkeley Laboratory. December 1970.
2) National Canners Association, Berkeley, California, Waste
Reduction in Food Canning Operations, Water Quality Office,
EPA 12060 — 08/70.
3) National Canners Association, Berkeley, California.-
Trickling Filter Treatment of Fruit Processing Waste Waters,
Project Number 12969 EAE, Water Quality Office, EPA, Sept. 1971.
h) Chipperfield, P.N.J. Performance of Plastic Filter Media in
Industrial and Domestic Waste Treatment, JWPCF 32 1860-187^, 1967.
5) Jeris, J. S. A Rapid COD Test, Water and Waste Engineering
^t (5) 89-91, 1967.
6) Report on EPA Project No. 12060 HFY "Dry Caustic Peeling of
Clingstone Peaches on a Commercial Scale" scheduled for
publication in 1972.
24
-------
REDUCED WASTE GENERATION BY
ALTERNATE VEGETABLE BLANCHING SYSTEMS**
by
Dr. Jack W. Rails, * Harry J. Maagdenberg, *
Nabil L. Yacoub, * and Walter A. Mercer*
INTRODUCTION
The heating of vegetables prior to terminal preservation (blanching) is an
essential operation for satisfactory final product quality; ' The blanching
treatment produces several desirable changes in the raw vegetables. Pri-
marily, enzymes are thermally inactivated to stabilize the food components
against rapid chemical changes. Gases, most importantly oxygen, are dis-
placed from the food during the blanching. For several vegetables, the
blanching step results in physical changes in the vegetable which improves
subsequent operations such as washing, peeling, or filling into containers.
The blanching step may provide a useful removal of certain contaminants
on, or in the raw food.
The disadvantages in vegetable blanching using steam or hot-water are loss
of nutrients, lower product yields and the formation of large volumes of
high strength liquid wastes. Surveys^) of canneries have shown that an
average of 40 percent of total BOD in liquid waste from vegetable process-
ing results from hot-water or steam blanching (shown in Figure 1). New
methods of blanching which generate low volumes of liquid wastes would
have obvious advantages for environmental protection during vegetable
processing.
Blanching methods to replace the traditional steam and hot-water systems
and to minimize generation of liquid waste require heat transfer media of
controlled water content. Vegetables are 70-92 percent water and during
heating exert a partial vapor pressure of water in the gas phase of a
closed system. The key to low water volume blanching is heating the vege-
table with little or no loss of compositional water to form a liquid waste.
^Western Research Laboratory, National Canners Association, Berkeley,
California 94710
##This investigation was supported by funds from the Environmental Pro-
tection Agency, Office of Research and Monitoring, under Grant No. 12060
PAV, and the National Canners Association.
25
-------
PERCENT OF TOTAL BOD DUE TO BLANCHING
ASPARAGUS
BEANS, SNAP
BEETS (& PEELING)
CORN
PEAS
PUMPKIN
SPINACH
50
Figure 1. Percent of Total BOD Due to Blanching
The most promising concept for low water volume blanching is the use of
microwave energy. Microwaves' ' have the property of internal heating
from energy released by reorientation of water molecules. The use of
microwave energy has been studied for blanching of a number of vegetables.
Recent studies on microwave blanching of corn-on-cob' ', brussel sprouts'^)
and potatoes* ' have been reported.
A modification of steam blanching to reduce the volume of liquid waste
generated (called IQB) has been reported^) recently by Lazar, Lund and
Dietrich.
A second potential low water volume method of vegetable blanching is the
direct use of hot natural gas combustion products in combination with sup-
plemental water vapor as a heat transfer medium.
A unit, which we have called a "hot-air blancher" for direct heating of
vegetables was one of four blanching methods compared in this project.
EXPERIMENTAL PLAN
To evaluate the potential usefulness of microwave and hot-air blanching of
seven major vegetables commodities, simulators of possible commercial
scale units were operated in conjunction with simulators of commercial
26
-------
hot-water and steam blanching equipment.
The microwave unit used in this study was a Varian Model COS 5A Micro
wave Conveyor shown schematically in Figure Z. The specifications for
the microwave blanching unit are tabulated in Appendix A.
Figure 2. Top and Side View of Microwave Blancher
The hot-air blanching unit was designed by Magnus on Engineers, Inc. , and
fabricated by Heat and Control Inc. Outline drawings of the hot-air blan-
chings are shown in Figures 3 and 4. The specifications for the hot-air
blanching unit are shown in Appendix B.
The steam and hot -water blanching was simulated in a single unit which
was the third stage of the pilot washer provided to the National Canners
Association under U.S. Atomic Energy Commission Contract AT (04-3)-
536. Outline drawings for the steam and hot-water blancher are shown
in Figures 5 and 6. The specifications for the steam and hot-water blan-
cher are listed in Appendix C.
-------
150 GFH NAT OAS
AT 8* WC.
4" VENT
ACCESS OPENINGS
1" STEAM INLET
7VZHP 230/460 3PH 60 Hr
1755 RPM
COMBUSTION AIR BLOWER
230/460V 3PH GOHz 500WATT5
193
Figure 3. Top View of Hot-Air Blancher
V4 HP D C CONVEYOR DRIVE
1ZOV 60 HZ A C15KVA POWER
5UPPU AT OPERATOR'S CONTROL/
POWER UNIT.
7ViHP Z30/460 3PH.60HZ
1755 RPM
1" STEAM INLET
COMBUSTION AIR BLOWER
230/460V 3PH 60Hz
500 WATTS
DRAIN
19 3'/z"
Figure 4. Side View of Hot-Air Blancher
28
-------
2 HEADERS, SIDE BY SIDE, WATER, STEAM
PIVOT POINT FOR \
CONVEYOR CHASSIS
WHITE NEOPRENE
CURTAINS
ADJUSTABLE LEGS
THIS UNIT ONLY
99"
Figure 5. Side View of Water and/or Steam Blancher
DRIVE UNIT SUPPORTED
FROM CONVEYOR CHASSIS.
SEPARATE REMOVABLE
COVERS.
IT'-
3
VENT
r
I—
I
_~
tn
-r
Figure 6. End View of Water and/or Steam Blancher
-------
The unit was operated as a steam blancher by passing steam into a spray
head manifold above the conveyor belt. The unit was operated as a hot-
water blancher by circulating a fixed volume of water held in the blancher
tank through an automatically controlled (steam heated) tubular heat ex-
changer.
Raw vegetables were supplied to the project by member canners and were
transported by refrigerated truck to the Berkeley Laboratory where the
blanching stimulators were installed. A series of short duration experi-
ments were conducted over a range of operating conditions for each blan-
ching unit to determine good operating conditions. The conditions selected
for longer duration experiments were based on weight changes, product
appearance and residual peroxidase levels.
During the longer duration runs, wastewater samples were collected on
a grab and composite basis. The wastewater samples were analyzed for
pH, COD and SS. Samples from each of the blanching units were analyzed
for significant vitamins and minerals, prepared, (i.e. corn cutting, beet
peeling, pumpkin blending and screening) and canned for later quality evalu-
ation.
The quality evaluation of the canned samples had several facets. Sets of
samples of each commodity were presented to a laboratory taste panel con-
sisting of 16 tasters. The panel was repeated four times for each sample
set for a total of approximately sixty judgements. The sets of four diff-
erent samples were presented in paper cups marked L., M, N, and O.
The panelist "was asked to rank the four samples after tasting with 4 de-
noting the worst flavor and 1 the best flavor. Therefore, if four identical
samples were judged, the average score would be 2.50. A scoring sheet
used to record the panelist ranking of the samples is shown in Figure 7.
A second evaluation of the canned samples was made by experienced qual-
ity graders from the U.S. Department of Agriculture Processed Fruit and
Vegetable Inspection Division. The samples were shipped to Stockton, Cali-
fornia from where they were distributed by the USDA to individual inspec-
tors. This quality grading developed a number reflecting primarily the
appearance of the sample.
An analysis was made of headspace gas in cans representing each blanch-
ing variable for each commodity. The method used was essentially that
described(S) using gas chromatography.
30
-------
TASTE PANEL
Please taste and rank samples in order of flavor preference. Take com
pleted scoring sheets and used sample tray to cutting room.
Code Flavor Ranking
1 = Best; 4 = Worst
M
N
Date Tasters' Initials
Figure 7. Scoring Sheet for Taste Panel
31
-------
The fourth quality evaluation was made by visual examination of washed
and dried empty cans from each blanching variable. The cans were scored
4 if badly corroded, 3 if moderately corroded, 2 if slightly corroded and
1 if without visible corrosion.
The fifth quality measurement was made for level of vitamins and minerals'''
significant for each commodity.
32
-------
EXPERIMENTAL RESULTS
Asparagus Blanching
The green asparagus used was obtained from Washington in two spaced
deliveries. The stalks were trimmed by hand to five inch lengths (cut-
ting of the butt ends). The asparagus was blanched in three of the four
units; the hot-air blancher was not completely installed while fresh can-
ning asparagus was available. The results from the short duration ex-
periments are tabulated in Table 1.
The results of longer term experiments in asparagus blanching are tabu-
lated in Table 2.
Table 3 tabulates the wastewater volume and characteristics for green
asparagus blanching in three experimental units.
Green Pea Blanching
The green peas used for the blanching studies were Alaska variety freezer
peas taken from the flume between the third stage prewasher and the hot
water blancher at a commercial freezing plant. The experiments were
conducted with a single sample of washed peas due to mechanical failure
of a rental refrigerated truck on route from Weston, Oregon to Berkeley
with the first load of peas. The peas received in the second delivery
were loaded at a temperature of 70°F into a section of a refrigerated truck
held at 40° F. The peas in the boxes located in the center of the stack did
not lose heat rapidly enough to avoid souring. The bulk of the soured peas
were sorted out on receipt and only the better quality material used in
the blanching experiments. The peas used were of sufficient quality to
provide useful measurement of blanching effects except for organoleptic
evaluation.
The results of the short duration experiments on blanching of green peas
are tabulated in Table 4.
The longer term blanching experiments with green peas are summarized
in Table 5.
The wastewater volume and characteristics for blanching of green peas
in four experimental units is tabulated in Table 6.
33
-------
Table 1.
Run
No.
Raw
ASP-7
ASP-8
ASP-9
ASP -10
ASP -11
ASP-12
ASP -13
ASP-14
ASP -15
ASP-16
ASP -17
ASP-32
Short Duration Blanching Runs for Green Asparagus in Three
Experimental Units
Blanching
Unit
N.A.
5 kw
Microwave
ti
Tt
11
11
4 kw
Microwave
ri
3 kw
Microwave
ii
ti
ii
5 kw
Microwave
Feed Rate
Lb/Hr
N.A.
49
240
300
160
105
100
225
225
66
86
113
257
Residence
Time, Sec
N.A.
673
84
84
160
281
398
130
130
281
206
160
84
Temp,
OF
N.A.
183
183
151
151
151
210
210
210
210
210
210
144
Peroxidase
Activation,
0.192
In-
Slope
Over blanched
0.193
0.210
0.160
0.010
0.285*
0.300*
0.135
0.175
0.175
0.233
Steam Injection
ASP-33
ASP-34
ASP-35
ASP-1
ASP-2
ASP-18
ASP -19
ASP-20
ASP-3
ASP-5
ASP-21
ASP-22
ASP-23
ASP -27
M
ii
ii
Steam
M
II
II
II
Hot Water
ii
it
M
it
ii
168
168
N.R.
323
331
400
267
268
120
172
278
288
343
267
160
104
130
135
100
79
100
134
227
147
90
66
52
90
144
144
144
212
212
200
200
200
180
190
180
180
180
190
0.055
0.165
0.080
Overblanched
0.008
0.005
0.003
0.00
0.007
0.004
0.04
0.04
0.10
0.007
N.A. = Not Applicable
N.R. = Not Recorded
*Higher values due to lower moisture content of sample.
34
-------
Table 2. Longer Term Blanching Runs For Green Asparagus in Three
Experimental Units
Feed Peroxidase
Run Blanching Feed Rate Time, Residence Temp Product Inactivation
No. Unit Lb/Hr Min Time, Sec °F Yield, % Slope
Raw N.A. N.A. N.A. N.A.
ASP-38 5 kw 110 45 145
Microwave
Steam Injection
ASP-36 Steam 180 60 100
ASP-37 Hot Water 120 60 90
N.A. N.A.
144 91
200
180
94
104
0.168
0.06
0.00
0.02
N.A. = Not Applicable
Table 3. Wastewater Volume and Characteristics for Green Asparagus
Blanching With Three Experimental Units
Run
No.
ASP-38
ASP-36
ASP-37
Blanching Wastewater
Unit Volume, Gal
5 kw 1.3
Microwave
Steam Injection
Steam 4. 3
Hot Water 100
S ample
Collected
45 Min
Composite
60 Min
Composite
15 Min
Grab
30 Min
Grab
45 Min
Grab
60 Min
Grab
60 Min
Composite
COD,
mg/1
3510
2490
51
72
105
128
101
SS,
mg/1
44
40
1
0
0
0
1
pH
6.8
6.7
7.7
7.7
8.1
7.4
7.7
35
-------
Table 4. Short Duration Blanching
Experimental Units
Run Blanching Feed Rate
No. Unit Lb/Hr
Raw N.A. N.A.
P-14 5 kw 138
Microwave
Steam Injection
P-16 " 139
P-15 0 kw 167
P-7 Hot-Air 133
P-8 Hot-Air 300
Steam Injection
P-9 " 300
P-10 " 343
P-ll " 369
P-12 " 1200
P-l Steam N.R.
P-2 " 150
P-4 Hot Water 274
P-5 Hot Water 192
N.A. = Not Applicable
Table 5. Longer Term Blanching
Experimental Units
Feed
Run Blanching Feed Rate Time
No. Unit Lb/Hr Min
P-17 5 kw 222 54
Microwave
Steam Injection
P-13 Hot-Air 710 46
P-3 Steam 180 55
P-6 Hot Water 208 58
Raw N.A. N.A. N.A.
Runs For Green Peas in Four
Residence Temp,
Time, Sec °F
N.A. N.A.
160 150
130 150
160 150
720 225
120 220
120 205
120 226
120 237
120 250
62 180
90 180
62 180
90 185
Peroxidase In-
activation, Slope
1.75
0.58
0.51
1.80
0.01
0.03
0.08
0.18
Overblanched
0.14
0.85
0.02
0.93
0.07
Runs For Green Peas in Four
, Residence Temp
Time, Sec °F
160 (15 min) 150
200 (39 min)
120 255
90 180
N.A. N.A.
Peroxidase
Product Inactivation
Yield, % Slope
98 0.60
99 0.14
100 0. 013
99 0.043
N.A. 1.75
N.A. = Not Applicable
36
-------
Table 6
Run
No.
P-17
P-13
P-3
P-6
. Wastewater Volume and Characteristics for Green Peas Blanching
With Four Experimental Units
Blanching Wastewater Sample
Unit Volume, Gal Collected
5 kw 4. 25 54 Min
Microwave Composite
Steam Injection
Hot-Air 0. 005 None
Steam 4. 0 55 Min
Composite
Hot Water 100 15 Min
Grab
30 Min
Grab
45 Min
Grab
58 Min
Grab
58 Min
Composite
cop,
mg/1
54,300
N.M.*
41, 000
1,760
3,900
4,550
6,000
3,920
SS,
mg/1
630
N.M.
3,700
113
176
180
192
170
pH
4.2
N.M.
4.6
4.6
4.6
4.7
4.6
4.4
*N. M. = Not Measured
37
-------
Green Bean Blanching
The green beans used in the short duration blanching runs were picked
up at a cannery in Eugene, Oregon and transported to Berkeley in an
air conditioned station wagon. The beans were pole beans which had
been snipped and size graded. A field run distribution of sizes 1, 2,
and 3 were used. The results of the short duration blanching runs for
green beans are tabulated in Table 7.
The green beans used for the longer duration runs were picked up in Junc-
tion City, Oregon and transported to Berkeley in two air conditioned station
wagons. The beans were cut bush beans of number 3 sieve size. The re-
sults for the longer term blanching experiments with green beans are tabu-
lated in Table 8.
The wastewater volumes and characteristics from longer term blanching
of green beans are tabulated in Table 9.
Corn-on-Cob Blanching
The corn used in the blanching experiments was obtained in Eugene, Ore-
gon on September 8, 1971. The corn was shipped to Berkeley in the husks.
Commercial scale corn husking and cutting equipment was loaned to NCA
by the Green Giant Company from their plant in Belvidere, Illinois.
Corn was husked and a portion cut for blanching as cut kernels. In the
initial run of cut kernels through the hot-air blancher, about one tenth of
the feed weight (95 Ib) stuck on the wire mesh conveyor belt and caramel-
ization of the starchy liquid adhering to the corn kernels took place. It
was not possible to get an accurate product yield (recorded weight was
77 Ib). The conveyor belt was cleaned by using hand brushing of the mov-
ing belt (at maximum speed setting) with steam injection into the unit and
a continuous water spray on the belt at the product discharge end. The
cleaning took 27 min and used 34 gal of fresh water. The cleaning waste-
water composite had a COD of 17, 900 mg/1 and a SS of 3, 210 mg/1.
The lack of practical blanching of cut kernel corn with the hot-air blan-
cher made it necessary (for comparative purposes) to run all four blan-
ching units using corn-on-cob.
The results of short duration blanching runs on corn-on-cob in the four
experimental units are tabulated in Table 10.
The results of longer term blanching of corn-on-cob in the four experi-
mental blanchers are tabulated in Table 11.
38
-------
Table 7
Run
No.
Raw
3 Sieve
BN-6
BN-7
BN-8
BN-9
BN-10
BN-1
BN-2
BN-3
BN-4
BN-5
BN-11
BN-12
BN-13
BN-14
BN-15
BN-16
Short Duration Blanching Runs
Experimental Units
Blanching Feed Rate,
Unit Lb/Hr
N.A. N.A.
Size
5 kw 85
Microwave
Steam Injection 3 Sieve Size
'« 111
3 Sieve Size
M 108
2 Sieve Size
" 129
2 Sieve Size
" 120
1 Sieve Size
Hot-Air 170
Steam Injection 3 Sieve
" 200
3 Sieve Size
" 109
3 Sieve Size
tt 150
3 Sieve Size
" 200
3 Sieve Size
» 203
2 Sieve Size
M 300
1 Sieve Size
Steam 180
3 Sieve Size
•i 172
3 Sieve Size
172
3 Sieve Size
n 124
2 Sieve Size
for Green
Residence
Time, Sec
N.A.
281
206
206
180
130
183
183
303
233
183
136
103
217
217
90
217
Beans in
Temp,
OF
N.A.
146
130
130
112
98
220
250
250
250
250
250
250
180
190
190
190
Four
Peroxidase
activation,
In-
Slope
Optical Density
Greater than 2
0.41
0. 44
0.42
0.53
0.81
>1. 0
0.19
0.03
0.03
0.06
0.12
0.38
0.25
0.10
0.12
0.18
39
-------
Table 7.
Run
No.
BN-17
BN-18
BN-19
BN-20
BN-21
BN-22
BN-23
BN-24
Short Duration Blanching Runs for Green Beans in
Experimental Units (continued)
Blanching Feed Rate,
Unit Lb/Hr
Steam 138
1 Sieve Size
" 129
1 Sieve Size
Hot Water 146
3 Sieve Size
154
3 Sieve Size
• i 142
2 Sieve Size
" 120
2 Sieve Size
112
1 Sieve Size
» 100
Residence Temp,
Time, Sec °F
90 190
217 190
291 190
182 "
182 M
227 "
182 "
227 "
Four
Peroxidase In-
activation, Slope
0.20
0.16
0.04
0.05
0.08
0.09
0.08
0.11
1 Sieve Size
40
-------
Table 8. Longer Term Blanching Runs For Cut Green Beans in Four
Experimental Units
Feed Peroxidase
Run Blanching Feed Rate, Time Residence Temp Product Inactivation
No. Unit Lb/Hr Min Time, Sec °F Yield, % Slope
Raw N.A. *
BN-26 5 kw
Microwave 132
Steam Injection
BN-25 Hot-Air
Steam Injection
BN-27 Steam
BN-28 Hot Water
N.A.
132
n
341
n
193
117
N.A.
50
60
50
60
N.A.
206
333
217
291
N.A.
130
250
190
190
N.A.
92
82
94
98
Optical
Density^ 2
0.53
0.06
0.07
0.06
*N.A. = Not Applicable
Table 9. Wastewater Volume and Characteristics for Cut Green Bean
Blanching With Four Experimental Units
Run
No.
Blanching Wastewater Sample COD SS,
Unit Volume, Gal Collected mg/1 mg/1
BN-26 5 kw
Microwave 2.4
Steam Injection
BN-25 Hot-Air 0.043
Steam Injection
BN-27 Steam 4.25
BN-28 Hot Water
100
50 Min 1, 470
Composite
60 Min 917
Composite
56 Min 5,420
Composite
15 Min 150
Grab
30 Min 200
Grab
45 Min 370
Grab
60 Min 490
Grab
60 Min
Composite
330
pH
46
88
102
1
4
3
10
8
6.5
7.7
6.1
7.5
7.3
7.1
6.9
7.3
41
-------
Table 10. Short Duration Blanching Runs for Corn-on-Cob in Four
Experimental Units
Run
No.
Raw
CN-4
Blanching
Unit
N.A.*
5 kw
Microwave
Feed Rate,
Lb/Hr
N.A.
82
Residence
Time, Sec
N.A.
422
Temp,
°F
N.A.
142
Peroxidase In-
activation, Slope
0.110
Overblanched
Steam Injection
CN-5
CN~6
CN-1
ii
11
Hot-Air
100
194
400
224
133
240
140
140
255
0.008
0.008
0.028
Steam Injection
CN-2
CN-3
CN-7
CN-8
CN-9
CN-11
*N.A. =
ii
it
Steam
M
ii
Hot Water
320
202
201
172
266
187
330
390
561
658
435
373
255
260
195
195
195
190
0.034
0.005
Overblanched
Overblanched
0.020
0.04
Not Applicable
Table 11. Longer Term Blanching Runs For Corn-on-Cob in Four
Experimental Units
Run
No.
Raw
CN-14
CN-10
CN-15
CN-12
Feed Peroxidase
Blanching Feed Rate Time Residence Temp, Product Inactivation
Unit Lb/Hr Min Time, Sees °F Yield, % Slope
N.A. N.A.
5 kw
Microwave 159
Steam Injection
Hot-Air 360
Steam Injection
Steam 220
Hot Water 230
N.A. N.A. N.A. N.A. 0.110
60 224 130 95 0.067
60 330 260 98 0.022
60
47
435
437
195 98
190 96
0.040
0.067
42
-------
The wastewater volumes and characteristics for longer term blanching
of corn-on-cob are tabulated in Table 12.
Red Beet Blanching
A mixture of small and medium sized, washed, red beets were picked up in
Eugene, Oregon on September 15, 1971 and brought to Berkeley. The results
of short duration blanching runs with beets in the four experimental units
are tabulated in Table 13. The results of longer term blanching of beets are
tabulated in Table 14.
The wastewater volumes and characteristics for longer term blanching of
beets are tabulated in Table 15.
Pumpkin Blanching or Wilting
The pumpkins used in the blanching experiments were obtained near Gridley,
California on October 19, 1971 and transported whole to the Berkeley Lab-
oratory. The pumpkin was cut by hand into random sized pieces (1 in.
square up to 3 in. square) and the seeds removed.
The results of short duration blanching runs for pumpkin are tabulated in
Table 16. The results from the longer term blanching experiments with
pumpkin pieces are tabulated in Table 17. The wastewater volumes and
characteristics for blanching of pumpkin pieces are tabulated in Table 18.
Spinach Blanching
The spinach used in blanching experiments were obtained from Walla Walla,
Washington. The spinach received at the cannery on October 27, 1971 was
destoned and washed. The washed spinach was packed in plastic lined
lug boxes; crushed ice was added to keep the product cool during the trans-
port period. The spinach arrived in Berkeley in excellent condition on the
evening of October 29.
The results of short duration runs for microwave and hot-air blanching of
spinach are tabulated in Table 19. No short duration runs were made for
steam and hot-water blanching because bench scale work done earlier on
samples of fresh market spinach had established that complete peroxidase
inactivation could be accomplished with a residence time of one minute at
180°F.
The results for the longer term blanching experiments with whole leaf
spinach are tabulated in Table 20.
43
-------
Table 12. Wastewater Volume and Characteristics for Corn-on-Cob
Blanching With Four Experimental Units
Run
No.
CN-14
CN-10
CN-15
Blanching Wastewater Sample COD, SS,
Unit Volume, Gal Collected mg/1 mg/1 pH
5 kw
Microwave
Steam Injection
Hot-Air
Steam Injection
Steam
CN-12 Hot Water
0.75 60 Min 4,320 73
Composite
0.0024 60 Min 502 1
Composite
3.12 60 Min 9,380 90
Composite
110 47 Min 461 4
Composite
6.3
6.8
6.4
7.7
Table 13. Short Duration Blanching Runs For Red Beets in Four
Experimental Units
Run
No.
Raw
BT-4
Blanching
Unit
N.A.
5 kw
Microwave
Feed Rate,
Lb/Hr
N.A.
85
Residence
Time, Sec
N.A.
224
Temp,
°F
N.A.
130
Peroxidase In-
activation, Slope
1.140
Over blanched
Steam Injection
BT-5
BT-6
BT-1
ti
1!
Hot -Air
239
305
69
93
53
1100
130
130
258
0.145
0.210
Overblanched
Steam Injection
BT-2
BT-3
BT-9
it
it
Steam
Hot Water*
131
170
155
N.A.
625
390
330
480
258
250
198
200
0.073
0.100
0.04
0.04
*Earlier runs with fresh market beets
N.A. i* Not Applicable
44
-------
Table
Run
No.
Raw
BT-10
BT-7
BT-8
BT-11
*N.A,
Table
14. Longer Term Blanching Runs For Red Beets in Four Experimental
Units
Feed
Blanching Feed Rate Time
Unit Lb/Hr Min
N.A.* N.A. N.A.
5 kw 240 30
Microwave
Steam Injection
Hot-Air 157 60
Steam Injection
Steam 142 53
Hot-Water 150 60
= Not Applicable
Residence
Time, Sec
N.A.
93
625
660
510
15. Wastewater Volume and Characteristics
Temp,
OF
N.A.
130
250
195
198
for Red
Product
Yield, %
N.A.
100
94
96
99
Peroxidase
Inactivation,
Slope
1.14
0.105
0.045
0.038
0.075
Beet Blanching
With Four Experimental Units
Run
No.
BT-10
BT-7
BT-8
BT-11
Blanching Wastewater
Unit Volume, Gal
5 kw 0.50
Microwave
Steam Injection
Hot-Air 0.007
Steam Injection
Steam 4.75
Hot-Water 100
Sample
Collected
30 Min
Composite
60 Min
Composite
53 Min
Composite
15 Min
Grab
30 Min
Grab
45 Min
Grab
60 Min
Grab
60 Min
Composite
COD
mg/1
321
1,530
7,240
165
247
295
617
370
ss,
mg/1
47
10
424
5
8
19
20
14
pH
5.3
7.0
5.0
7.0
-
7.0
6.9
6.8
7.0
45
-------
Table 16
Run
No.
Raw
PM-1
PM-2
PM-3
PM-10
PM-11
PM-12
PM-4
PM-5
PM-6
PM-7
PM-8
PM-9
. Short Duration Blanching
Experimental Units
Blanching Feed Rate
Unit Lb/Hr
N.A.* N.A.
5 kw 50
Microwave
Steam Injection
5 kw 50
Microwave
Steam Injection
" 150
Hot-Air 200
Steam Injection
" 140
" 65
Steam 150
" 224
M 256
Hot-Water 400
'• 200
n 200
Runs For Pumpkin Pieces
Residence
Time, Sec
N.A.
680
680
390
330
390
1100
766
560
340
227
510
510
in Four
Temp, Peroxidase In-
oF activation, Slope
N.A.
80
140
140
235-
250
250-
265
250-
265
193
194
196
190
192
209
7.43
0.64
0.13
0.10
1.8
0.10
0.33
0.002
0.047
0.11
7.0
1.7
0.033
#N.A. = Not Applicable
46
-------
Table 17. Longer Term Blanching Runs For Pumpkin Pieces in Four
Experimental Units
Run
No.
Raw
PM-13
Blanching
Unit
N.A.*
5 kw
Feed Rate,
Lb/Hr
N.A.
132
Feed
Time
Min
N.A.
60
Residence
Time, Sec
N.A.
390
Temp,
°F
N.A.
140
Product
Yield, %
N.A.
94
Peroxidase
Inactivation,
Slope
7.43
1.22
Microwave
Steam Injection
PM-14 Hot-Air 127 60 625 250- 86 0.079
Steam Injection 255
PM-15 Steam 140 60 560(32) 196 93 0.0057
650(28)
PM-16 Hot-Water 120 60 510 210 94 0.013
*N.A. = Not Applicable
47
-------
Table 18. Wastewater Volume and Characteristics For Pumpkin Piece
Blanching With Four Experimental Units
Run
No.
PM-13
PM-14
PM-15
PM-16
Blanching Wastewater
Unit Volume, Gal
5 kw 2.5
Microwave
Steam Injection
Hot -Air 0.005
Steam Injection
Steam 4. 5
Hot-Water 110
Sample
Collected
60 Min
Composite
60 Min
Composite
60 Min
Composite
15 Min
Grab
30 Min
Grab
45 Min
Grab
60 Min
Grab
60 Min
COD,
mg/1
6,560
138
10,360
220
450
780
910
640
SS,
mg/1
84
1
48
5
15
15
16
10
PH
6.2
6.0
6.1
7.4
7.2
7.0
7.0
7.2
Composite
48
-------
Table 19. Short Duration-Blanching Runs For Spinach in Four Experimental
Units
Run
No.
Raw
SP-1A
Blanching Feed Rate,
Unit
N.A. *
5 kw
Microwave
Lb/Hr
N.A.
17
Residence Temp
Time, Sec. °F
N.A. N.A.
224 140
Peroxidase In-
activation, Slope
0.72
N.R.**
Steam Injection
SP-1B
SP-2A
ii
Hot -Air
16
N.R.
133 140
330 250
O ve r blanche d
Dried
Steam Injection
SP-2B
N.R.
*N.A. = Not Applicable
**N.R. = Not Recorded
183
250
O ve r blanche d
49
-------
Table 20. Longer Term Blanching Runs For Spinach in Four Experimental
Units
Feed Peroxidase
Run Blanching Feed Rate Time Residence Temp, Product Inactivation
No. Unit Lb/Hr Min Time, Sec °F Yield, % Slope
Raw
SP-1
N.A.
5 kw
N.A.
38
N.A.
60
N.A.
93
N.A.
140
N.A.
68
0.72
0.034
Microwave
Steam Injection
SP-2 Hot-Air 145
Steam Injection
SP-3 Steam 230
SP-4 Hot-Water 140
60
26
30
164
79
66
250
180
180
69
91
104
0.004
0.0008
0.065
N.A. = Not Applicable
Table 21. Wastewater Volume and Characteristics For Spinach Blanching
With Four Experimental Units
Run
No.
Blanching
Unit
Wastewater
Volume, Gal
Sample
Collected
COD,
mg/1
SS,
mg/1
pH
SP-1 5 kw 0.63
Microwave
Steam Injection
SP-2 Hot-Air 0.003
Steam Injection
SP-3 Steam 6.4
SP-4 Hot Water 100
60 Min 280
Composite
60 Min 992
Composite
26 Min 4740
Composite
15 Min
Grab
30 Min
Grab
30 Min
Composite
192
256
216
37
5.6
1
206
22
29
35
6.9
6.1
6.4
6.4
6.6
50
-------
The wastewater volumes and characteristics for longer term blanching of
spinach with the four experimental units are tabulated in Table 21.
Samples for Quality Evaluation
Canned samples were prepared for each of the seven vegetables studied in
this project; a six month storage at 50 - 80OF (ambient temperature of in-
terior storage in Berkeley pilot plant) before examination was part of the
project plan.
Taste Panel Results
Only two of the seven vegetables studied in this project were quality evalu-
ated at the time this report was written. The canned samples of green as-
paragus and green beans were presented to a laboratory taste panel. The
results of the taste panel evaluation are tabulated in Table 22.
Vitamin Analyses
The blanched samples and canned samples were analyzed for levels of sig-
nificant vitamins. The levels of vitamins found in the blanched samples are
tabulated in Table 23. The results for the vitamin content of canned samples
of asparagus and green beans are tabulated in Table 24. These two commod-
ities were the only two analyzed up to the time this report was written.
The results of analysis of blanched samples for their content of calcium,
magnesium, phosphorous and iron where significant are tabulated in Table
25. No analyses for mineral content of canned samples were conducted
since the mineral content of the total can contents would not change except
for slight increases due to traces of the elements of interest in the water
and salt used for canning brine.
The results of headspace gas analysis by gas chromatography for stored
canned samples of green asparagus and green beans are tabulated in Tables
26 and 27.
The results for estimates of internal corrosion of cans used for asparagus and
green beans as tabulated in Table 28 show no significant effect due to the
blanching method used.
51
-------
Table 22. Taste Panel Evaluation of Canned Samples After Storage For
Six Months
Commodity Cumulative Taste Panel Ranking*
Asparagus
Microwave 3.1
Steam 2.2
Hot-Water 2.5
Commercial 2.2
Green Beans
Microwave 2.9
Hot-Air 2. 4
Steam 2.5
Hot-Water 2.1
*Best flavor = 1, Worst Flavor = 4
-------
Table 23. Vitamin Levels in Vegetables Blanched in Four Experimental Units
Commodity
Asparagus
Raw
Microwave
Steam
Hot-Water
S
Green Peas
Raw
Microwave
Hot-Air
Steam
Hot-Water
S
Green Beans
Raw
Microwave
Hot-Air
Steam
Hot-Water
S
Corn-on-Cob
Raw
Microwave
Hot-Air
Steam
Hot-Water
S
A*
**#
***
*#*
***
***
***
***
***
***
#*#
#*#
***
***
***
***
***
***
Vitamin Content, mg/lOOg
Bj B, B£ C Niacin
.,
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
*4
37
35
38
38
35
02
07
10
14
07
06
01
**
*=}
#5}
**
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
22
19
20
20
17
17
16
13
15
01
12
13
12
12
12
01
11
14
12
11
1]
02
*** 19
14
22
18
2.2
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
24
27
^ £t *T" *T* TT *l*
24
05
06 ***
05 ***
04 ***
05 ***
05 ***
05
18 ***
23 ***
16 ***
19 ***
19 ***
04
1.55
1.82
1.46
1.62
0.04
2.
2.
2.
2.
1.
0.
0.
0.
0.
o.
0.
0.
1.
2.
2.
2.
1.
0.
10
04
14
07
73
06
52
65
76
59
51
18
41
23
06
18
91
10
S = Standard Deviation (mg/lOOg)
* Vitamin A in USP units/100 g
** Enzyme used gave poor results, sample used up in other analyses,
*** Analysis not planned due to low level in commodity
**** Vitamin C lost in all samples during storage before analysis.
53
-------
Table 23. Vitamin Levels in Vegetables Blanched in Four Experimental
Units (continued)
Commodity
Red Beets
Raw
Microwave
Hot -Air
Steam
Hot Water
S
Pumpkin
Raw
Microwave
Hot -Air
Steam
Hot Water
S
Spinach
Raw
Microwave
Hot -Air
Steam
Hot-Water
S
A
##*
*#*
*##
*#*
*#*
9630
8420
6760
13, 180
7760
400
384
696
702
605
624
25
*** 0.06 ***
0. 05 ***
0.07 *##
0.05 **#
0.04 ***
0.001
3JC3JCSfc ### ###
3JC5JC5JC 3yC?JC2jC «C2JC3!c
5JC2JC9JC M( nCnC «C!JC^C
*** *** ***
### *** ***
*** 0. 08 ***
*** 0.13 ***
*** 0.14 ***
*** 0.10 ***
*** 0. 07 ***
0.01 *##
C Niacin
6.9 0.24
6. 8 0. 21
7.5 0.26
5.6 0.20
7.9 0.20
0.5 0.02
*** 0. 49
### 0.38
*** 0.59
*## 0. 27
sSfstesk n *%**)
-rn*--r- \J * J Lt
0.04
***
#### ***
***
***
***
###
54
-------
Table 24. Vitamin Content of Canned Vegetables After Storage for Six Months
Vitamin Content, mg/lOOg
Commodity
Asparagus
Microwave
Steam
Hot -Water
S
Green Beans
Microwave
Hot -Air
Steam
Hot-Water
S
ll
0.05
0.05
0.06
0.01
0.03
0.04
0.03
0.03
0.01
12 16
0. 10 ***
0.09 ***
O.ii ***
0.01
0.05 N.C.
0.07
0.06
0.05
0.001
C
3.79
3.62
3.62
0.05
***
***
***
***
Niacin
0.64
0.76
"0.71
0.03
0.35
0.39
0.34
0.34
0.02
S s Standard Deviation (mg/lOOg)
*** Analysis not planned due to low level in commodity
N.C. = Not complete at time of report
55
-------
Table 25. Mineral Content of Vegetables Blanched in Four Experimental Units
Mineral Content,
Commodity
Asparagus
Raw
Microwave
Steam
Hot-Water
S
Green Peas
Raw*
Microwave
Hot -Air
Steam
Hot-Water
S
Green Beans
Raw
Microwave
Hot-Air
Steam
Hot-Water
S
Corn-on -Cob
Raw
Microwave
Hot-Air
Steam
Hot-Water
S
Red Beets
Raw
Microwave
Hot-Air
Steam
Hot-Water
S
Ca
21.5
22.1
22.0
20.2
3.1
14.0
14.2
13.2
14.0
4.4
40
46
52
39
41
7.3
***
***
***
***
***
***
***
+.i,-jLf-j^
-r"i*-i*
***
***
Mg
15.7
15.5
14.4
16.3
1.1
28.5
29.1
28.1
28.3
5.1
27
29
33
26
27
7.9
J> Jl* vU
ff, rftff.
***
***
***
***
*o> »«-.
•K* T*
***
•VVf
*JU^L.«I*
i* *r*ir
***
P
67.0
77.0
70.0
69.5
5.3
104
114
101
96
17.7
36
40
48
36
37
3.4
80.3
91.3
78.5
92.5
iff
6.7
22.7
26.0
26.6
23.4
21.2
2.4
mg/lOOg
Fe
***
***
***
*##
1.03
1.06
1.00
1.03
0.21
1.21
1.28
1.50
1.19
1.15
0.39
*l» il* •A,
*r *n* T
***
* •**
ff, fft
***
,u ,u ,o
*i»ir»-«v
bi,«(, a,
T"!* •"«>
***
***
***
***
56
-------
Table 25. Mineral Content of Vegetables Blanched in Four Experimental
Units (continued)
Mineral Content, mg/lOOg
Commodity Ca Mg P Fe
Pumpkin
Raw 9.2 6.7 11.6 ***
Microwave 8.8 12.9 21.5 #*#
Hot-Air 13.5 10.9 13.9 ***
Steam 10.5 9.6 14.2 ***
Hot-Water 9.2 7.2 10.0 ***
S 1. 3 0. 6 1.0
Spinach
Raw
Microwave
Hot-Air
Steam
Hot Water
S
S = Standard Deviation (mg/lOOg)
*Sample lost
*** Analysis not planned due to low level commodity
62.2
86.0
60.5
65.0
50.5
1.6
63.5
89.5
65.0
65.5
49.0
1.9
20.0
50.2
42.4
42.4
31.0
2.4
3.1
3.4
3.2
3.3
3.1
0.35
57
-------
Table 26. Headspace Gas Analysis of Canned Green Asparagus Stored Six
Months
Blanching Headspace
Unit Volume, ml
Microwave
Steam
Hot-Water
15.4
10.8
8.6
Percent
N
COz
Argon
HZ +02
83.7 7.2 6.5 2.6
93.6 3.9 0.0 2.5
85.8 3.7 2.4 4.0
Original
02
20.0
22.5
20.9
Table 27. Headspace Gas Analysis of Canned Green Beans Stored Six
Months
Blanching
Unit
Microwave
Headspace
Volume, ml
28.8
Percent
N2 C02 H2
93.1 4.9 0.0
Argon
+ Oz
2.0
Original
02
22.4
Hot-Air
Steam
Hot-Water
29.1
28.7
24.4
88.9 5.5 3.7 1.9
92.5 4.8 0.4 2.3
91.4 5.0 1.6 2.0
21.4
22.2
22.0
58
-------
Table 28. Estimation of Extent of Internal Corrosion For Cans Used to
Store Vegetables For Six Months at 65 - 85°F
Commodity Extent of Corrosion, Visual*
Asparagus
Microwave 2
Steam 2
Hot-Water 2
Commercial 3
Green Beans
Microwave 1
Hot-Air 1
Steam 1
Hot-Water 1
* 4 * severe; 3 = moderate; 2 = slight; 1 = no corrosion
DISCUSSION
Asparagus Blanching
The results on asparagus blanching are incomplete at the present time be-
cause the hot-air blancher was not completely installed until after the end of
the asparagus harvesting season.
The peroxidase level in green asparagus is readily reduced to low levels by
steam or hot-water blanching. Rather long residence times with full five
kw power was required to reduce peroxidase levels to about 5 percent of
the original level as shown in Table 1.for microwave blanching.
The longer term run for microwave blanching of asparagus resulted in
only a 74 percent reduction of peroxidase content. This extent of reduction
may be satisfactory for a canned product, but would probably cause off-
flavor in frozen samples.
59
-------
Table 29. Comparison of Long Term Green Asparagus Blanching
Unit
Microwave
Steam
Hot Water
Peroxidase
Reduction, %
74
100
90
Wastewater
Gal/ Ton
24
53
1665
COD
Lb/Ton
.69
1.1
1.3
SS,
Lb/Ton
9 x 10~3
1.6 x 10'2
1.3 x 10~2
The most important comparison which is made from the results obtained in
this project is in the volume and characteristics of wastewater produced.
Table 29 tabulates the volume of wastewater, the COD of the wastewater,
and the SS content of the wastewater all based on ton of raw product blanched.
The volume and strength of the wastewater produced during microwave blan-
ching of green asparagus are much lower than those of steam or hot-water
blanching.
Green Pea Blanching
The experiments with green peas were the first to directly compare all
four blanching methods. The loss of the first shipment of raw peas due
to truck failure limited the number of short duration runs used to estab-
lish good operating conditions. The conditions selected for the longer
term microwave blanching were not sufficient to accomplish more than a
66 percent reduction in peroxidase content. The conditions selected for
the operations of the other blanching units gave greater than 90 percent
reduction of initial peroxidase levels. The results from measurement of
wastewater generated during the four longer term blanching runs were the
first indication of the dramatic reduction in wastewater volume during hot-
air blanching. The production of only a few ml of steam condensate during
the hot-air treatment of vegetables was found for every commodity studied.
On the basis of wastewater volumes only, the hot-air blanching of vegetables
is truly a low water volume method.
60
-------
The very strong liquid waste produced during steam or hot-water blanching
of green peas emphasizes, the potential improvement of shifting to hot-air
blanching as a water pollution abatement practice. The results useful in
comparing the four types of blanching are tabulated in Table 30. The COD,
SS, and pH of the steam condensate was not measured since the volume was
less than that normally used in the determinations.
Table 30. Comparison of Long Term Green Pea Blanching
Unit
Microwave
Hot-Air
Steam
Hot Water
Peroxidase
Reduction, %
66
92
99
98
Wastewater
Gal /Ton
43
1.8 x 10-2
48
1,000
COD
Lb/Ton
19.3
N. M. *
16.6
32.7
SS,
Lb/Ton
.22
N. M.*
1.5
1.4
* N. M. = Not Measured
Green Bean Blanching
The unique part of the short duration blanching experiments with green
beans, as tabulated in Table 7, was the use of uniform sizes of raw beans,
The beans were taken from size graders at the cannery and were the small-
est sizes (1, 2 and 3). The beans were snipped but uncut and would normally
be canned without cutting. The time and temperature required for adequate
blanching is a function of the size of the vegetable price being blanched.
Generally it is desirable to size or maturity grade raw vegetables to obtain
optimum blanching conditions. No rigorous study of the effect of sieve size
on blanching requirement was made in this, project due to lack of time and
raw material. The beans used for the longer term blanching runs were
cut No. 3 sieve size so the conditions used were selected from short dur-
ation experiments which used whole No. 3 sieve size beans.
61
-------
The data comparing major results of the longer term blanching experi-
ments with green beans are tabulated in Table 31.
Table 31. Comparison of Long Term Green Bean Blanching
Unit
Microwave
Hot-Air
Steam
Hot-Water
Peroxidase
Reduction, %
89
99
99
99
Wastewater
Gal/ Ton
48
.25
47
1,710
COD,
Lb/Ton
.59
2 x 10~3
2.1
4.7
SS,
Lb/ Ton
1.8 xlO-2
2xKT4
4x 10-2
.11
Corn-on-Cob Blanching
It was expected to blanch the corn as whole kernel corn after cutting from
the cob since the bulk of corn for canning and freezing is blanched after cut-
ting. Due to the cut kernels sticking to the belt of the hot-air blancher, it
was not possible, within the time limitations, to study whole kernel corn
blanching.
There is a substantial production of both canned and frozen corn-on-cob,
so the study of corn-on-cob blanching would apply to a commercial product.
The results of the comparison of wastewater volume and characteristics
from the four blanching units are tabulated in Table 32. The wastewater
volume from the hot-air blancher is several orders of magnitude smaller
than those from hot-water and steam blanching. The wastewater from
the hot-air blancher is also much lower in COD and SS for each ton of
corn blanched.
62
-------
Table 32. Comparison of Long Term Corn-on-Cob Blanching
Unit
Microwave
Hot -Air
Steam
Hot-Water
Peroxidase
Reduction, %
39
80
64
39
Wastewater,
Gal /Ton
9.4
1.33 x 10-2
28.4
1,233
COD,
Lb/Ton
.34
5.6 x 10-5
2.22
4.70
ss,
Lb/Ton
5.7 x 10~3
-------
Table 33. Comparison of Long
Peroxidase
Unit Reduction, %
Microwave 91
Hot-Air 95
Steam 96
Hot-Water 93
Table 34. Comparison of Long
Term Red Beet
Wastewater,
Gal/ Ton
8.4
8.9 x 10~2
76
1,330
Term Pumpkin
Peroxidase Waste water,
Unit Reduction, % Gal/Ton
Mic r ow a ve 8 4
Hot-Air 99
Steam 99
Hot Water 99
Table 35. Comparison of Long
Peroxidase
Unit Reduction, %
Microwave 95
Hot-Air 99
Steam 99
Hot Water 91
38
7.1x 10-2
64
1,830
Blanching
COD,
Lb/Ton
2.2 x 10'3
1. Ix 10-3
4.6
4.1
Blanching
COD,
Lb/Ton
2.1
8.2 x 10-5
5.5
9.8
SS,
Lb/Ton
3 x 10~3
7.4xlO-6
.27
.16
SS,
Lb/Ton
2. 7 x 10"2
5.9 x 10-7
2. 6 x lO-2
1.5 x 10-1
Term Spinach Blanching
Wastewater
Gal /Ton
33
3.6 x 10-2
56
1430
COD,
Lb/Ton
7.8x lO-2
3 x lO'4
2.2
2.6
SS,
Lb/Ton
Ix ID'2
3 x 10"7
0.1
0.3
64
-------
product quality. Also, if any internal corrosion problem was going to oc-
cur due to inadequate blanching it would be evident after six months of stor-
age.
There was some concern that the vegetables blanched by microwave or hot-
air might contain higher levels of occluded gases than hot-water or steam
blanched material. One of the requirements of adequate blanching is the
removal of gases from the product so that headspace vacuum would be main-
tained during thermal processing and storage and excessive oxygen would
not cause product deterioration or internal corrosion of the can. Limita-
tion of time did not permit a direct measure of the gas content of vegetable
immediately after blanching. Fortunately, analysis of headspace gas in
the canned samples is useful to give an indication of the original content
of oxygen in the blanched product. The estimate of oxygen in the blanched
product at the time of canning can be made by direct measure of the volume
and the nitrogen peak in the gas chromatogram of the headspace gas. This
estimate assumes that the hot brine used to fill the can displaces gases from
the vegetable and that the gases released change the normal gas composition
after the container is sealed. The normal fate of oxygen in headspace gas
is a reaction with the container to form stannic oxide or autoxidation pro-
ducts of can liner enamels and/or product. The oxygen content of a normal
can of vegetables is usally very low after six months of storage. A hypo-
thetical situation will illustrate the potential changes in headspace gas com-
position at various stages of preparation and storage.
Total Percent
Condition Volume » N2 QZ CO2 Argon
Composition of air N.A. 78.08 20.95 0.03 0.93
Open can + vegetable 20 78 21 0. 0 1,0
Occluded gases 5 40 40 20 0
Brine filled can 20 68.5 25.7 5.0 0.75
Closed can 20 68.5 25.7 5.0 0.75
Closed can after
6 month storage 15 91. 25 1. 0 6. 75 1. 0
*Calculated at 760 Hg pressure and 0°C temperature
Without knowing precisely the composition of gases occluded in blanched
vegetables, it will be generally true for a single set of blanched samples
that the higher the residual nitrogen content, the higher the oxygen con-
65
-------
tent of the can at the time of closure. Therefore, the measured value of
residual nitrogen content of canned samples stored six months will be a
crude index of occluded oxygen in the blanched sample. The results shown
in Table 26 indicate that the content of occluded gases in green beans was
not significantly different among the material from each of the four blanchers.
A very important quality factor of the blanched vegetables was the taste panel
evaluation of flavor. As shown by the results in Table 22 the only unit which
shows less prefered flavor are the samples prepared from microwave blanched
asparagus and green beans.
66
-------
LITERATURE CITED
1. Potter, N.N. "Food Science" p. 479. The AVI Publishing Company,
Westport, Connecticut (1968).
2. Rose, W.W., Mercer, W.A., Katsuyama, A., Sternberg, R. W.
Brauner, G. V. , Olson, N. A. and Weckel, K. G. Production and dis-
posal practices for liquid wastes from cannery and freezing fruits and
vegetables. Environmental Protection Agency Water Pollution Control
Research Series 12060 - 03/71 p. 109 (1971).
3. Proctor, B.E. and Goldblith, S. A. Electromagnetic Radiation Fundamen-
tals and Their Application in Food Technology. Advances in Food Re-
search, 3: 120 (1951).
4. Huxsoll, C.C., Dietrich, W.C. Morgan, A.I., Jr. Comparison of
Microwave with Steam or Water Blanching of Corn-on-the-Cob. 1.
Characteristics of Equipment and Heat Penetration. Food Technology
24 (3): 290 (1970).
Dietrich, W. C., Huxsoll, C.C., Wagner, J.R. , and Guadagni, D. G.,
Comparison of Microwave with Steam or Water Blanching of Corn-on-
the-Cob. 2. Peroxidase Inactivation and Flavor Retention. Food Tech-
nology 24 (3): 293 (1970).
5. Dietrich, W.C., Huxsoll, C.C., and Guadagni, D. G., Comparison on
Microwave, Conventional and Combination Blanching of Brussel Sprouts
for Frozen Storage, Food Technology, 24 (5): 613 - 7 (1970).
6. Chen, S.C., Collins, J.L., McCarty, I.E. and Johnson, M.R., Blan-
ching of White Potatoes by Microwave Energy Followed by Boiling Water.
J. Food Sci. 36 (5): 742 (1971).
7. Lazar, M.E., Lund, Daryl B. and Dietrich, W.C., A new concept in
blanching (IQB), Food Technology, 25 (7): 684 (1971).
8. National Canners Association, "Laboratory Manual for Food Canners
and Processors", AVI Publishing Company, Inc. Westport, Conn. (1968).
9. Anon., Official Methods of Analysis of the Association of Official Analy-
tical Chemists. Eleventh Edition. Association of Official Analytical
Chemists, Washington D. C. 20044(1970).
67
-------
Appendix A
MICROWAVE BLANCHING UNIT SPECIFICATIONS
Microwave frequency
Microwave power (2-2. 5 kw
power packs)
Entrance and exit port size
Belt
Belt speed
Cavity material
Finish
Power requirements:
Conveyor only
Air heaters only
Each power pack
2450 + 50 MHz
5 kw
4 in. high x 12 in wide
1/4 in.mesh, coated fibreglass
0-20' per min, reversible
Stainless steel
28 exterior; 4B
220 V: 3-phase; 60 Hz
1 kva
30 kva
5 kva
Adjustable 200-600 cfm
Air supply
Air temperature controllable to 250°F
(depending on rate of air flow)
Water requirements (each power pack) 1. 5 gpm at 20 psig/min
Steam 40 psig
68
-------
Appendix B
SPECIFICATIONS OF HOT AIR BLANCHING UNIT
Length:
Width:
Conveyor:
Conveyor width:
Conveyor drive:
Heater:
Blower:
Air temperature:
Product Capacity:
16. 5 ft
6 ft 6 in.
Stainless steel belt in two levels each with
flights, 3 in. high, and 12 in. apart
12 in.
Variable speed motor with 10 fold speed
range
Natural gas fired burners
Rated at 125, 000 Btu/hr
3800 standard cu ft/min
250°F Maximum
500 Ib/hr
69
-------
Appendix C
SPECIFICATIONS OF STEAM AND HOT-WATER BLANCHER
Length:
Width:
Belt width:
Material of Construction:
Bearings:
Conveyor: chain:
Shaft diameter:
Drapes:
Drive:
Belt speed:
Steam coil test pressure:
8.5 ft
18. 5 in.
15.25 in.
18-8 (304) stainless steel
Bronze brushed with grease fittings
No. 40, extended pitch
1 in.
B-N standard type, 16 GA. mesh 3/16 in.
openings with 2. 5 in high flights at 6 in.
spacing
4.9-49 rpm, U.S. Varidrive RT. angle,
0.5 hp, 3 phase, 60 cycle
4-40 fpm
225 psig
70
-------
A FIELD STUDY ON THE APPLICATION
OF INDIVIDUAL QUICK BLANCHING*
by
JL.JL.
Daryl B. Lund
INTRODUCTION
The preparation of vegetables for preservation by canning, freezing or
dehydration results in large volumes of high strength organic waste
streams. With increased awareness of the impact of these seasonal
streams on the environment and waste treatment facilities, vegetable
processors are looking for technologically-effective and economically-
feasible methods of treating or reducing these streams. For the pur-
pose of reducing total plant effluent and biological oxygen demand
(BOD), attention has focused on the blanching operation. This opera-
tion serves several functions including removal of tissue gases,
inactivation or activation of enzymes ", reduction of microbial load,
cleansing of product and wilting of tissue to facilitate packing.
These objectives are accomplished by heating the vegetables in either
hot water or steam(l). Both hot water and steam blanching produce
liquid wastes high in BOD, and both result in loss of water soluble
nutrients. Based on data reported by Weckel et al^ ' for two Wiscon-
sin canning plants, a 9070 reduction in blancher effluent would reduce
total plant waste flow by 10 to 20% and, more significantly, reduce
total plant BOD by 20 to 50%. The National Canners Association^)
estimated that if a new blanching method were used for the seven vege-
tables processed in the largest tonnage which reduced waste water
strength by 50%, a total of approximately 70 million pounds of BOD and
40 million pounds of suspended solids would be eliminated from treat-
ment plant loadings.
In the abatement of waste water flow and loss of solids from product
in canning and freezing plants, a study was initiated in 1970 to
design a blanching process which would have a waste water flow of only
10% of a commercial hot water blancher. The project was supported by
the University of Wisconsin and the USDA, and was conducted by M. E.
Lazar and D. B. Lund at the Western Marketing and Nutrition Research
Division, USDA. The project resulted in a new concept of heating foods
*This investigation was supported by the College of Agricultural and
Life Sciences, and the Graduate School, University of Wisconsin,
Madison; the Oconomowoc Canning Company, Oconomowoc, Wisconsin; the
Wisconsin State Department of Natural Resources; the Wisconsin
Canners and Freezers Association and the USDA Western Marketing and
Nutrition Research Division, ARS, Albany, California.
**Department of Food Science, College of Agricultural and Life Sciences,
University of Wisconsin, Madison.
71
-------
and the application to blanching was demonstrated^'-*'. The process,
individual quick blanch (IQB) , required further evaluation and,
therefore, the Western Laboratory conducted a study utilizing IQB
prior to freezing while the evaluation of IQB for blanching prior to
canning was conducted in a Wisconsin canning plant. This paper pre-
sents the results of the evaluation of IQB as a precanning process.
METHODS
The IQB unit was furnished by the Western Research Laboratory for use
in a Wisconsin canning plant. The unit (described by Lazar ejt al(4))
consisted of two insulated chests, one heated by direct steam and the
other heated indirectly, and had a capacity of about 300 pounds per
hour. The product, taken from the process line just prior to entering
the conventional pipe blancher, was distributed in a single layer
(approx. 1 lb/ft^) on a mesh belt moving through the steam chamber.
The residence time was such that the mass average temperature of the
product was that desired for blanching. The product was then trans-
ferred to a much slower moving belt traveling through the second
chamber and remained there until blanching was accomplished. The
product was hand packed into 303 x 407 cans to a given fill weight,
brine and hot water were added and the can was sealed. The cans were
inserted into the plant conveying line to go through the continuous
retort process.
Initial investigations by Lazar et al/ showed that the reduction in
waste flow from blanching was enhanced by slightly drying the product
prior to steaming. Therefore, some of the runs were conducted on the
product which was dried by a 5 to 20% weight reduction in an alternat-
ing upflow-downflow hot (160-180°F) air drier.
The effluent from the IQB blancher was collected for the entire run
(usually 100 pounds of product) and was analyzed for constituents by
the Wisconsin Department of Natural Resources Laboratory. Sample
analysis included five-day BOD, total solids, suspended solids, total
and soluble phosphorous, total organic-, ammonia-, and nitrate-
nitrogen, and pHv").
The "conventional" blanching system used in this canning plant was a
pipe blancher. The water usage was monitored by inserting a water
meter in the water make-up line and recording daily water require-
ments. By knowing the daily case pack on that line, the water usage
per case could be determined. It should be noted, however, that the
value for water usage in this report (gal/case) does not represent the
actual effluent flow from the pipe blancher. Besides the make-up line,
there is also the direct addition of steam as the heat source for main-
taining water temperature and heating the product. For an estimation,
approximately 10 pounds of steam would condense for every 100 pounds
of product, and, therefore, the actual effluent flow would be about
0.2 gal/case higher than that reported here for pipe blancher s. Water
samples for analysis from the pipe blancher were obtained from the de-
watering reel overflow and were analyzed in the same manner as those
from the IQB unit.
72
-------
In order to establish the heat-hold times required for the IQB process,
preliminary tests were conducted on each vegetable. It was observed
that for peas the conventional blanching operation resulted in inacti-
vation of peroxidase and, therefore, inactivation of peroxldase was
used as the criterion for establishing the IQB process times. For
corn, green beans and lima beans, the pipe blanching operation was
carried out in water at 170°F. Thus, the IQB process was chosen so
that the final mass average temperature of these products would be
170°F.
To evaluate the effect of the IQB blanching process on the ultimate
quality of the canned product, a taste panel was used to compare the
IQB to conventionally blanched-canned vegetables after one, three and
six months' storage. Difference and preference judgments were used.
In this study the variety of vegetables used were: peas--Alsweet,
corn—Midway, green beans—Slim green, and lima beans—unknown. The
case equivalence of vegetables is: peas--15.75 Ib/case, corn—15.75
Ib/case, green beans—13.05 Ib/case and lima beans--13.50 Ib/case.
RESULTS AND DISCUSSION
Table 1 presents the blanching times used in the current study. It
can be seen that the blanching times for the IQB process are consider-
ably shorter than for the conventional pipe blancher, as would be pre-
dicted based on heat transfer rates from steam as compared to hot
water. However, it should be pointed out that each processor has his
own blanching process and that, therefore, the conventional process
presented here may actually be longer than necessary.
The characterization of waste water flow, yield of canned product and
sensory evaluation for peas are given in Tables 2, 3 and 4, respec-
tively. The column heading, "Drying (%)" refers to the weight reduc-
tion accomplished prior to steaming and holding in the IQB process.
"Pipe" refers to the conventional pipe blancher.
Table 2 characterizes the waste water flow from IQB and pipe blanchers
for peas. Water flow (gal/case) for the pipe blancher is considerably
lower than that reported by Weckel e£ a_l^ '. They reported water
usage of 3.38 gal/case, effluent BOD of 3270 ppm and total solids of
0.72% (w/w) for a pipe blancher. Since there are no established guide-
lines for the water make-up flow in pipe blanchers, it would be ex-
pected that there would be large variations in total water flow with
accompanying variations in BOD and total solids. Recall, however,
that the water usage reported in these tables does not include the
water from condensation of the heating steam. As pointed out in the
Methods section, this would amount to about 0.2 gal/case.
The can loss reported was calculated by assuming the peas were 20%
total solids and, therefore, one pound of pea solids being discharged
from the blancher was equivalent to five pounds of peas. IQB without
a drying step resulted in a 68% decrease in total blancher effluent.
The characteristics of the effluent was not, however, different from
73
-------
Table 1. Times and Temperatures for Pipe and IQB Blanching
Blanching Method
Pipe Blancher
IQB Heat
Hold
Product
Peas
Corn
Time Temp.
(rain) (°F
Green Beans Lima Beans
0.5
0.75
Time Temp. Time Temp. Time Temp.
fain) (°F)
170
0.33 212
0.50
0.33 212
1.33
0.33 212
1.33
Table 2. Characterization of Waste Water Flow from Pea Blanching
Drying
0
6.5
17.2
Pipe
Water Flow
(gal/case)
0.32
0.09
0.06
0.76
T.S.
C%)
2.33
2.92
3.32
2.31
B.O.D.
(ppm)
16700
15600
19600
15100
Can Loss
2.1
1.1
1.0
4.8
Table 3. Yield of IQB and Pipe-Blanched Canned Peas
% Drying
0
6.5
17.2
Pipe
Overall Can Loss
2.1
2.0
13.3
4.8
Overfill
0
5.69
74
-------
the effluent from the pipe blancher; that is, the percent total solids
and BOD were approximately equal in both effluent streams. A possible
explanation might be that the pipe-blancher effluent is in equilibrium
with the pea; that is, the water emerging from pea blanchers would
only build up a certain BOD and total solids, and would, from that
time on, not increase in BOD or total solids.
As expected, as the surface moisture was removed from the peas the
total effluent flow from the IQB unit decreased. The increase in
total solids and BOD for the 17.2% Dry-IQB was probably due to the
fact that as the steam condensed and ran off the peas, surface solids
were washed off. Further addition of water to the surface of the peas
would probably have resulted in only diluting the effluent stream.
The yield of peas from pipe and IQB blanchers is given in Table 3.
The overall can loss was calculated from the actual weight of peas
processed divided by the initial weight of peas. For the 0% Dry-IQB
and the pipe blancher the overall can loss will be equal to the can
loss expressed in Table 2. However, for the other two IQB processes--
6.5 and 17.2% Dry--the overall can loss in this table is greater than
that reported in Table 2. This can be explained by the fact that the
peas, once dried, did not completely rehydrate when exposed to steam
and, therefore, the overall can loss was greater than that calculated
on the basis of solids in the blanch water. For the process that was
used, approximately 10 pounds of steam would condense for every 100
pounds of product and, therefore, theoretically enough condensed steam
would be available to rehydrate the peas up to about 10% drying.
Apparently, with the high rate of condensation and the decreased sur-
face tension due to solids on the surface and high surface temperature
(212°F), the condensed steam ran off the peas instead of being ab-
sorbed. It could be postulated then that the overall can loss figure
could be reduced by allowing the dried-blanched peas to soak, thereby
reabsorbing the water lost during drying. Or, for our particular
case, we should observe a can overfill approximately equal to the
overall can loss minus the can loss based on solids in the effluent.
Column 3 of Table 3 presents drained weight data for the processes
expressed as a percent overfill. The drained weights were determined
after one montHs storage at 85°F. It can be seen that IQB dried-canned
peas did not regain all of the moisture lost during drying even after
the retorting operation and one month's storage. This indicates that
some of the moisture was irreversibly lost during drying. The irre-
versible effect of drying on water reabsorption has been discussed
elsewhere''-'.
The difference and preference sensory evaluation of IQB- compared to
pipe-blanched canned peas is given in Table 4. A plus sign indicates
that the IQB was preferred over the pipe-blanched canned peas and a
minus sign indicates a preference for the pipe-blanched product. The
number refers to the level of significance of the difference. It can
be seen that the IQB process produces an acceptable canned product
except when excessive drying is used. This was to be expected because
it was observed that when peas were dried over 7%, the skins started
to split and this resulted in visible differences between the pipe
75
-------
Table 4.
Drying
a)
0
6.5
17.2
Table 5.
Drying
a)
0
8.9
11.8
18.5
Pipe
Table 6.
Drying
(7.)
0
8.9
11.8
18.5
Pipe
Difference and Preference Between IQB and Pipe-Blanched
Canned Peas
Difference and Preference at:
1 month 3 months 6 months
N.S. +5 1
5 - 0.1 +1
- 0.1 - 0.1 - 0.1
Characterization of Waste Water Flow from Corn Blanching
Water Flow T.S. B.O.D. Can Loss
(gal/case) (7.) (ppm) a)
0.27 2.55 14800 1.33
0.01 3.14 19900 0.34
<0.01 1.48 8000 <0.01
<0.01 5.07 24700 <0.01
1.19 2.51 18000 6.28
Yield of IQB and Pipe-Blanched Canned Corn
Overall Can Loss Overfill
a) a)
1.33
0.34 3.44
2.90 9.55
11.20 3.86
6.28
76
-------
and IQB blanched peas. These split skins produced a cloudy brine in
the IQB product. Based on these results, it does appear that the IQB
process with some drying would result in an acceptable canned product
while reducing blancher effluent by up to 88%.
The data on corn blanching are presented in Tables 5, 6 and 7. Table 5
shows that IQB with no drying reduced blancher effluent by 77% and
drying to 8.9% reduced it by 92% compared to pipe blanchers. Further
drying reduced the blancher effluent more drastically to less than
0.01 gal/case of canned corn. The low percent total solids and BOD
of the effluent from the 11.9% drying-IQB process were not expected
and the only reasonable explanation is that this corn was very mature
and very well washed prior to blanching. Comparing the data on the
pipe blancher to that of Weckel ot^ al&) the water usage reported here
is much lower with higher percent total solids and higher BOD. Weckel
et aj..(2) reported values of 2.10 gal/case, 1.10% T.S. and 8,420 ppm BOD.
The can loss data show that IQB processing results in a 69% decrease in
can loss without drying and at least a 98% decrease with extensive
drying. These data were calculated on the basis that corn averaged
25% total solids.
Table 6 presents the yield data from the blanching process for corn.
As with dried peas, the overall can loss for dried corn was in excess
of that calculated on the basis of solids in the effluent. However,
dried corn did reabsorb more moisture during steaming in the IQB pro-
cess than dried peas did. This is evidenced by the fact that the 8.9%
Dry-IQB processed corn lost only the solids in the effluent and re-
gained in steaming all of the moisture lost in drying. Similarly, the
11.8 and 18.5% Dry-IQB corn showed greater recovery of moisture than
the 17.2% Dry-IQB peas. These results were to be expected based on
the fact that with corn there is a cut surface which can be dried and
rehydrated much more readily than a surface with a skin such as peas.
Besides reabsorbing the moisture during steaming, corn also absorbed
water during retorting and subsequent storage. This is illustrated
by the data in Table 6 as percent overfill. The absorption by the
11.8% Dry-IQB corn again was probably due to having overripe corn while
that given for the 18.5% Dry-IQB corn may indicate that drying to that
extent results in an irreversible skin formation hindering reabsorption
of moisture.
Table 7 shows that the IQB processed corn and pipe-blanched canned corn
were indistinguishable by sensory evaluation except for the 18.5% Dry-
IQB. In that instance, the difference was highly significant with the
pipe-blanched product being preferred. This difference was due to the
darker color of the IQB corn. This darker color was evident as the
corn came out of the dryer. Even though the drying temperature was at
or below 180°F, caramelization did take place during the long residence
time required for this degree of drying.
Tables 8, 9 and 10 present the results of green bean blanching. IQB
without drying and 6.6% Dry-IQB resulted in a decrease in blancher ef-
fluent of 86% and 957., respectively, as shown in Table 8. Unlike peas
and corn, the blancher effluent for IQB and the pipe-blancher for green
77
-------
Table 7.
Drying
(7.)
0
8.9
11.8
18.5
Table 8.
Drying
0
6.6
Pipe
Table 9.
Drying
0
6.6
Pipe
Table 10.
Drying
0
6.6
Difference and Preference Between IQB and Pipe-Blanched
Canned Corn
Difference and Preference at:
1 month 3 months 6
N.S. N.S.
N.S. N.S.
N.S. N.S.
- 1 - 0.1
months
N.S.
N.S.
N.S.
- 0.1
Characterization of Waste Water Flow from Green Bean
Blanching
Water Flow T.S. B.O.D.
(gal/case) (7.) (ppm)
0.26 0.47 3250
0.09 0.70 5260
1.92 0.94 5900
Yield of IQB and Pipe-Blanched Canned Green Beans
Overall Can Loss Overfill
(7.) (7.)
0.86
2.3 1.07
11.4
Can Loss
0.86
0.49
11.4
Difference and Preference Between IQB and Pipe-Blanched
Canned Green Beans
Difference and Preference at:
1 month 3 months
+ 0.1 N.S.
- 0.1 0.1
6 months
1.0
- 0.1
78
-------
beans did differ in their percent total solids and BOD. This can
probably be accounted for by the fact that green beans are cut and
then blanched. With the large air spaces exposed in the cut green
bean, there would be an extended surface area for leaching, and with
water blanching the solids would be leached out. Consequently, the
percent total solids and BOD are lower for the IQB effluent. With the
6.6% Dry-IQB there was a higher BOD than with the pipe-blancher efflu-
ent. This would probably be due to the lower water runoff in the IQB
process resulting in higher BOD. With green beans the potential saving
to the canner in terms of can loss would be even greater than with peas
or corn. There was a 92% reduction in can loss with 0% Dry-IQB blanch-
ing. The green beans were assumed to be 10% total solids for this cal-
culation.
The yield of IQB blanched green beans, given in Table 9, shows that even
with a 6.6%, drying the IQB process is more efficient. Green beans, like
corn, reabsorbs a large percentage of the moisture during steaming that
was removed by drying.
Table 10 shows that although there appears to be a difference between
IQB and pipe-blanched, canned product, there was no preference. With
the 6.6% Dry-IQB, the pipe-blanched green beans were preferred but this
was due to the sloughing defect observed in the Dry-IQB product. Ap-
parently during drying, the skin separated from the green bean and
sloughed during retorting and storage. The 0% Dry-IQB did not exhibit
this sloughing.
Lima bean blanching data are presented in Tables 11, 12 and 13. In
Table 11, a noticeable figure is the 20.6 gal/case for pipe-blancher
water usage. We have no explanation for this other than the possibility
that the water control valve was mistakenly turned wide open. Since
the water usage was evaluated by gathering water meter readings over a
two-week period, there is no doubt about the figure. IQB reduces the
blancher effluent by 99% under these circumstances. It would probably
be a fair estimate that with lima bean blanching, we would expect water
usage in the range of that for the other vegetables tested (0.76-1.92
gal/case).
The high water usage resulted in a blanch water lower in BOD and percent
total solids but also afforded more losses due to leaching. The greater
leaching loss is illustrated by the large percent can loss. With IQB
the can losses were reduced 97% and more than 99.5% for 0% dry and
10.6% Dry-IQB, respectively. Lima beans were assumed to be 32.5% total
solids for the can loss calculations.
The yield of lima beans in the IQB process was significantly better
than that of the pipe-blanching process. Lima beans, like corn and
green beans, reabsorbed during steaming a substantial fraction of the
water removed during drying. This was not entirely expected since lima
beans, like peas, have a skin. The percent overfill for lima beans was,
however, expected to be high since lima beans normally gain weight dur-
ing retorting and storage.
79
-------
Table 11.
Drying
a)
0
10.6
Pipe
Characterization
Blanching
Water Flow
(gal/case)
0.27
< 0.01
20.6
of Waste Water
T.S.
a)
1.02
0.92
0.55
Flow from Lima
B.O.D.
(ppm)
6550
6100
3800
Bean
Can Loss
(%)
0.58
<0.01
21.4
Table 12.
Drying
(7.)
0
10.6
Pipe
Yield of IQB and Pipe-Blanched Canned Lima Beans
Overall Can Loss
(%)
0.58
1.6
21.4
Overfill
a)
-
17.8
-
Table 13. Difference and Preference Between IQB and Pipe-Blanched
Canned Lima Beans
Drying Difference and Preference at:
(%) 1 month 3 months 6 months
0 5.0 - 0.1 N.S.
10.6 0.1 - 0.1 N.S.
80
-------
The results of the difference and preference testing, Table 13, indi-
cate that after six months' storage there was no difference as prefer-
ence between IQB and pipe-blanched canned lima beans. At three months'
storage there was a large difference and a strong preference for the
pipe-blanched canned product. It was noticed that at that time the
IQB-processed lima beans appeared to have a large number of free skins
in the product. Apparently with longer storage times these differences
disappeared.
Table 14 presents information on the characteristics o"f the effluent
flow from IQB and pipe-blanching systems for all four of the vegetables
processed. The BOD/T.S. ratio was variable but the average for all the
runs on a commodity were not significantly different. The averages
range from 0.59/1 to 0.69/1.
The BOD/N/Phos. ratio indicates that of the four vegetables processed,
the pea and lima bean blancher effluent could be treated directly with-
out addition of nitrogen or phosphorous. It has been reported that
for stabilization of a secondary waste treatment facility, a BOD/N/Phos.
ratio of 100/5/1 is adequate. Consequently, with corn and green beans
the blancher water could be best treated by combining it with a high
nitrogen source prior to secondary treatment.
CONCLUSIONS
The results of this investigation indicate that IQB can successfully be
used for blanching vegetables prior to canning. The IQB process results
in reduction of blancher effluent by 68 to 99% while maintaining prod-
uct quality. Specific results include:
1) Peas: Blancher effluent was reduced at least 687o in the IQB process
compared to pipe-blanching. Excessive drying of the peas resulted in
skin breakage with resulting cloudy brine and loss of product quality.
2) Corn: IQB reduced blancher effluent between 77 and 99%. There was
no product quality loss except under high predrying conditions where
the product was darker in color than the control.
3) Green Beans: An 86 to 9570 reduction in blancher effluent was ob-
tained using IQB. Product quality was comparable to pipe-blanched
canned product except when predried. With predrying, sloughing was
evident.
4) Lima Beans: Reductions up to 997a were accomplished in the blanch-
ing operation using IQB. With drying, the loss of skins seemed to
impair product quality.
81
-------
Table 14. Characteristics of Effluent from Blanching
Product
Peas
Corn
Green Beans
Lima Beans
Method
Pipe
IQB 0%C
IQB 6.5%
IQB 17.2%
Pipe
IQB 0%
IQB 8.9%
IQB 11.8%
IQB 18.5%
Pipe
IQB 0%
IQB 6.6%
Pipe
IQB 0%
IQB 10.6%
B.O.D./T.S.
(ppm/ppm)
0.66/1
0.71/1
0.53/1
0.59/1
0.72/1
0.58/1
0.63/1
0.54/1
0.49/1
0.62/1
0.70/1
0.76/1
0.69/1
0.64/1
0.66/1
a. N = Total organic + ammonia + N0_ - N0_ -
b. Phos. = Total phosphorus
c. Percent
drying prior to
steaming in IQB
B.O.D./Na/Phos.b
(ppm/ppm/ppm)
100/5.13/1.26
100/4.31/1.23
100/6.15/1.72
100/3.78/0.99
100/2.08/0.71
100/2.17/0.69
100/1.37/0.66
100/1.61/0.69
100/1.33/0.70
100/3.84/0.94
100/3.49/0.73
100/2.92/0.68
100/5.63/0.84
100/7.11/0.69
100/2.40/0.72
Nitrogen
LITERATURE CITED
1. LEE, F. A. The blanching process. Adv. Food Res. 8:63(1958).
2. WECKEL, K. G., RAMBO, R. S., VELOSO, H., and von ELBE, J. H.
Vegetable :anning process wastes. Res. Rpt. No. 38, College of
Agricultural and Life Sciences, University of Wisconsin, Madison
(1968).
3. NATIONAL CANNERS ASSOCIATION. Research Information Bulletin
No. 170. January (1971).
82
-------
4. LAZAR, M. E., LUND, D. B. and DIETRICH, W. C. IQB: A new concept
in blanching. Food Technol. 25:684 (1971).
5. LUND, D. B., BRUIN, S. L., and LAZAR, M. E. Internal temperature
distribution during individual quick blanching. J. Food Sci.
37:163 (1972).
6. Standard methods for the examination of water and waste water.
13th ed. American Public Health Association, Inc., 1790 Broadway,
New York, New York (1971).
7. VAN ARSDEL, W. B. Food dehydration. I. Principles. The AVI
Publishing Co., Inc., Westport, Conn. (1963).
83
-------
WASTE CONTROL IN THE PROCESSING OF SWEET POTATOES
by
N. V. Colston and C. Smallwood, Jr.*
INTRODUCTION
In North Carolina plans are underway to develop a vegetable pro-
cessing industry to complement existing fresh market outlets.
North Carolina grows about one third of the nation's total sweet
potato crop and ranks second behind Louisiana in processing. This
year three North Carolina plants are actively engaged in processing
sweet potatoes. Last year there were four—one being forced to
discontinue canning operations because of associated water pollution
problems. If the vegetable processing industry is to grow in North
Carolina, or perhaps even to continue to exist, new and/or improved
methods and technology for coping with its local environmental impact
must be developed.
Tabor City Foods, Inc., of Tabor City, North Carolina, processes
approximately 45 percent of the State's pack. Located in an
economically depressed community of 3,000, the plant provides em-
ployment for about 500 people and cash-crop outlet for an unknown
number of farmers. The plant also contributes the majority of
wastes entering the city's outdated sewage treatment facility. The
city is presently in the process of building a new.sewage treatment
facility, which, by necessity, had to be overdesigned to accommodate
the canning plant waste. Realizing the associated problems of sweet
potato canning, Tabor City Foods sought assistance from North Carolina
State University. The industry and the University together developed,
sought, and were granted an Environmental Protection Agency Demon-
stration Grant to help alleviate waste problems, increase plant
efficiency, and develop a waste management technology for the sweet
potato processing industry.
The project's purpose is to make changes in equipment and operations
to demonstrate effective water and wastewater management in sweet
potato processing. The project encompasses waste abatement and water
use throughout the plant from fresh water intake through pretreatment.
The specific objectives are:
*Civil Engineering Department, North Carolina State University,
Raleigh, N. C.
**This investigation was supported by funds from the Environmental
Protection Agency, office of Research and Monitoring, under Grant No.
12060 FRW and Tabor City Foods, Tabor City, N. C.
85
-------
1) Install and/or modify a dry caustic peeling process and
demonstrate its effectiveness for water and waste
reduction.
2) Install and demonstrate wastewaters pretreatment facilities
for the reduction of waste loads.
3) Determine the economic implications of the water and
waste management techniques demonstrated.
4) Formulate guides for water and wastewater management in
sweet potato processing.
The 1971 processing season of September through December was used for
preliminary studies and analytical evaluations required to establish
bench mark quantities and characteristics of water consumption, waste
production, and plant operating procedures. This was necessitated by
the lack of information regarding the present "state of the art" of
sweet potato processing.
CANNING PROCESS
An outline and description of major sweet potato processing operations
are essential for understanding water consumption and waste production
characteristics. The major processing steps are:
Receiving and Unloading
Sweet potatoes arrive at the plant in trucks which are unloaded
either by a front-end loader or a large "vacuum cleaner-like"
apparatus. Some field dirt falls off the potato during the transfer
operations.
Washing
The potatoes are conveyed through a reel washer to remove dirt
attached to the potatoes.
Preheating
The potatoes are preheated in a water bath of approximately 105° F for
a couple of minutes to enchance the action of the lye bath.
Lye Bath
Potatoes are immersed in a boiling 15 percent lye solution for
approximately two minutes to facilitate peel removal and reduce
manual trimming operations. The greater the peel loss, the greater
the waste produced and the less usable product left.
86
-------
Peel Removal
Peels are removed by a rotary washer which removes most of the
softened peel and part of the potato.
Snipping
Large rotary snippers are used to remove roots or strings from sweet
potato ends.
Abrasive Peelers
Sandpaper-like counter rotating rollers are used to smooth the
potato surface.
Brush Washer
Counter rotating bristle rollers impart a final sheen to the surface
of the potato.
Trimming
The freshly peeled potatoes are inspected and manually trimmed.
Product not suitable for canning is rejected.
Sizing
A rotating drum with variable size openings separates potatoes by
sizes.
Slicing
Large potatoes move through a series of cutting machines which first
half and then quarter the potatoes.
Grading
Potatoes on the grading belt are manually checked for size and quality.
Filling
The raw product moves onto a circular hand pack filler with a series
of openings around its outer edge. Potatoes are then raked into cans
passing below as the circular top rotates.
Syruping
Most canned sweet potatoes are packed in a syrup medium of sugar and
water heated to a temperature just below boiling.
87
-------
Closing
A sealing machine places a lid on each can and applies pressure to
seal the can.
Retorts
High pressure steam retorts are used to cook the canned product for
varying periods of time, depending on can size, syrup content, and
the average temperature of the contents when placed in the retorts.
Cooling
On removal from the retorts, cans are passed through a cooling canal.
Labeling^ and Packaging
Labels are pasted on cans and the cans are placed in cases for storage
and eventual shipment.
Before the existing conventional process could be modified, a season's
operating data on the relationship of water usage and waste charac-
terization to plant production had to be established. The existing
laboratory at the plant was geared up to make typical sanitary engi-
neering analytical tests, and the laboratory technician was brought
to North Carolina State University for a week of intensive training.
Necessary equipment, chemicals, and supplies were purchased for the
plant laboratory.
The plant installed nineteen (19) water meters to determine unit
process use rates. Daily readings were taken of tons of input,
operating hours, and daily production. The breakdown of water con-
sumption per ton of sweet potatoes processed and per case of number
2-1/2 cans produced are given in Table 1.
The retorting operations utilizes the largest amount of water (38.8%)
of any single operation. There is no substantial amount of organic
material in this water. The water utilized for steam generation
and syrup production is consumptive in that it is either packed in
cans or evaporates.
Analytical quality measurements were made at Tabor City Foods and
at North Carolina State University. All procedures were in accor-
dance with the 1971 Environmental Protection Agency Methods for
Chemical Analysis of Water and Wastes. In addition, all samples
were passed through a twenty-mesh screen prior to analysis at the
request of the Environmental Protection Agency. A composite sample
consisting of four grab samples were taken at each sampling station
each operating day, or as often as feasible. Chemical oxygen demand,
settleable solids, temperature, and pH observations were made on each
88
-------
TABLE 1
Unit Process Water Use in Conventional
Sweet Potato Processing
Unit Process
First Washer
Preheat er
W/D Washer
Snippers
Abrasive Peeler
Brush Washer
Retort
Cleanup
Cooling
Boiler Water
Belt Wetting
Syr up ing
Gal /Ton
Input
79
15
280
110
140
96
1000
240
31
415
130
36
Gal/Case
#2-1/2 Cans
2.8
0.54
9.9
4.0
4.8
3.4
35.0
8.6
1.0
15.0
4.7
1.3
% of Total
Water Use
3.0
0.5
10.9
4.4
5.3
3.7
38.5
9.5
1.1
16.5
5.2
1.4
TOTALS
2572
91.0
100.0
89
-------
sample collected. Biochemical oxygen demand, suspended solids, dis-
solved solids, nitrogen, and phosphorus measurements were made less
frequently. The range and average concentrations of wastes flows
for the conventional unit processes are presented in Table 2.
Whole sweet potatoes were studied in the lab to determine the pounds
of COD, BOD, carbon, nitrogen, and phosphorus per pound of whole dry
weight. The sweet potatoes examined had an average moisture content
of 76 percent. One pound of sweet potatoes (dried at 103° C) was
found to produce 1.06 pounds COD, 0.49 pound EOD~, 0.38 pound of
carbon, 0.0184 pound of nitrogen, and 0.0016 pound of phosphorus.
If the poundage was based on the wet weight of the potato, these
figures have to be multiplied by 0.24. This means that for every
pound of sweet potato not put in cans and entering a liquid waste
stream, one can expect 0.252 pound COD, 0.118 pound BOD,., 0.091 pound
of total carbon, 0.0044 pound of nitrogen, and 0.000384 pound of
phosphorus.
The total pounds of BOD,., COD, total and suspended solids discharged
per ton of raw product input from conventional unit processes
utilized in sweet potato processing are presented in Table 3. The
data presented represents the waste load after passing samples through
a twenty-mesh screen. It is interesting to note that the major sources
of waste production (synonymous with product loss) are created by peel
removal, abrasive peeling, and snipping operations. All figures shown
in this table end up in the liquid waste stream.
Studies were undertaken to define and/or identify the mass balance
of sweet potatoes through the processing plant. As a result of these
investigations, the following information was generated:
1) Raw product studies revealed that 5 percent (100 Ibs/ton)
of the product when received was field dirt.
2) Solid waste generation studies revealed that 9.5 percent
(190 Ibs/ton) of raw product, unfit for canning for various
reasons, was trucked away for disposal.
3) Product yield studies revealed that 40 percent (800 Ibs/ton)
was placed in cans and became a saleable product.
4) Liquid waste studies revealed that 160 pounds of solids dried
at 103° C were generated per ton of raw product input
(Table 3) after screening. Dividing the 160 pounds by
0.24, the percent total solids in a raw sweet potato, gives
680 pounds of solids per ton of raw product input. Or, 33
percent of the raw product ends up in a liquid waste stream.
90
-------
TABLE 2
Waste Concentrations for Unit Processes Utilized in Conventional Sweet Potato Processing?4
Unit Process
BOD(mg/L)
Average Range
COD(mg/L)
Average Range
Total Nitrogen
as N(mg/L)
Average
TOTAL
EFFLUENT*
8,600 4000-13000
22,000 12000-31000
210
Total Phosphorus
as P(mg/L)
Average
First Washing
Preheater
Peel Removal
Snippers
Abrasive Peeling
Brush Washer
Retort
Cleanup
990
3,700
13,000
5,900
14,000
3,500
76
2,200
460-2400
2400-4500
7800-23000
2600-8600
7900-20000
1300-4700
44-110
530-6200
3,700
9,300
32,000
16,000
22,000
6,400
210
3,800
1300-8900
4700-14000
10000-45000
8100-40000
1600-40000
2000-9600
130-260
2200-10000
12
45
320
140
330
71
0
—
1.1
17.0
40.0
23.0
50.0
9.2
0
—
29.0
20-mesh screening
*Excluding Retort Waters
-------
TABLE 2 (continued)
Unit Process
First Washing
Preheater
Peel Removal
Snippers
Total Solids
(mg/L)
Average Range
2,100
Brush Washer
Retort
Cleanup
300
800-8700
8,400 6500-11000
35,000 12000-48000
13,000 5300-18000
M Abrasive Peeling 23,000 6600-36000
4,300 2800-8700
260-370
Suspended Solids
(mg/L)
Average Ranee
Settleable Solids
(ml/L)
Average Range
1,200
1,600
7,700
3,800
4,400
1,200
0
300-1500
600-2660
2500-10500
600-7100
1100-6700
350-4500
0
28
32
530
280
470
74
0
6-40
5-64
350-750
75-500
60-730
18-160
0
2,700 2200-3200
870
630-1100
TOTAL
EFFLUENT*
26,000 7000-67000
3,800 1400-8000
250
60-570
Mfter 20-mesh screening
*Excluding Retort Waters
-------
TABLE 3
Waste Loads Per Ton of Input for Unit Processes
Utilized in Conventional Sweet Potato Processing*
Unit Process
First Wash
Preheater
Peel Removal
Snippers
Abrasive Peeling
Brush Washer
Retort
Cleanup
Miscellaneous
BOD
Ibs/ton
0.7
0.5
30.0
5.5
16.0
2.8
0.6
4.4
0
COD
Ibs/ton
2.4
1.2
75.0
15.0
25.0
5.1
1.8
7.7
6.8
Total Solids
Ibs/ton
1.4
1.1
83.0
12.0
26.0
3.4
2.5
5.5
25.1
Suspended
Solids
Ibs/ton
0.8
0.2
18.0
3.6
5.1
1.0
0
1.8
0
TOTAL EFFLUENT
60.0
140.0
160.0
30.0
*Rounded off and after 20-mesh screening
93
-------
5) The sum of the percentages accounted for as dirt, solid waste,
yield, and liquid waste is 87.5 percent. The remaining 12.5
percent is believed to represent the quantity of sweet potato
discharged into the liquid waste stream that will not pass
a twenty-mesh screen. All waste samples were passed through
a twenty-mesh screen prior to analysis at the request of the
Environmental Protection Agency. This would indicate that a
total of 45.5 percent (910 Ibs/ton) of the raw product enters
the liquid waste stream prior to screening. Therefore, all
figures presented in Tables 2 and 3 should be adjusted upward
by 1.4 (45.5 * 33) to represent waste generation before
screening.
A summary of water use, lye consumption, and waste generation per ton
and per case of number 2-1/2 cans for conventional sweet potato canning
is presented in Table 4.
PROPOSED CHANGES AND PROCESS MODIFICATIONS
The 1971 processing data gathered from Tabor City Foods is believed
to represent the current "state of the art" of conventional sweet
potato canning technology. Table 4, the characterization summary,
dramatically indicates the severity of the problem facing sweet
potato earners. Each of these problem areas bears directly on a
processor's economic competitiveness and imposes a potential
pollutional load on the local environment. A processor, for example,
who is able to realize a greater yield, not only has more saleable
product for the same expenditure but reduces his cost of waste treat-
ment. A twofold gain!
The purpose of the second year of the EPA demonstration grant is to
design, install, demonstrate, and evaluate four techniques of
increasing yield, lowering canning costs, and reducing the environ-
mental impact of sweet potato canning. Specifically, four means of
assisting the processor and the environment will be demonstrated.
These are dry caustic peeling, lye reconditioning, high pressure water
system, and pretreatment of waste.
Dry Caustic Peeling
Conventional vat type (hot dip) lye peeling became the major technique
of removing the peels of fruits and vegetables during World War II.
The simplicity, economy, and labor saving advantages of lye peeling
allowed the U.S. to meet the demand for processed fruits and vegetables
at a time when there existed acute shortages of labor and materials.
The techniques of lye peeling developed during World War II are still
used today.
94
-------
TABLE 4
Characterization Summary of Conventional Sweet Potato Processing*
Parameter
A. Liquid t
BOD (Ibs)
COD (Ibs)
T. Solids (Ibs)
S. Solids (Ibs)
B. Solid Waste (Ibs)
C. Dirt
D. Water (gallons)
E. Lye (50%) (gallons)
Per Ton
60
140
160
30
200
100
2600
9.2
Per Case
2.1
5.0
5.7
1.0
7.1
3.5
92.0
0.32
*Rounded off
20-mesh screening
95
-------
In 1967-68, Graham, Huxsoll, et al, at the USDA's Western Research and
Development Division, Albany, California, announced the development of
a new method of peeling potatoes. Their dry caustic method was based
on the application of infrared heat to lightly caustic treated potatoes
followed essentially by mechanical peel removal.
A ten ton per hour infrared peeling system, based on the Graham-
Huxsoll model, is scheduled for installation in the Tabor City Foods'
plant this summer. The anticipated changes in operating character-
istics from application of this new technology are: 1) lower peel
loss, 2) lower water consumption, 3) lower lye consumption, 4) in-
creased product yield, and 5) disposal of generated solids as a
solid waste.
Lye Reconditioning
The use of a rotary drum filter for reconditioning lye by removing
solids and spent lye from the lye vat is expected to reduce the lye
consumption by increasing the useful life of the lye.
High Pressure Water System
Through the use of high pressure spray nozzles, equal or superior
removal efficiency can be obtained using less water. The use of
less water also means waste concentrations will be greater, facil-
itating easier pretreatment.
Waste Pretreatment
The installation of a vibrating screen followed by a rotary drum filter
is expected to reduce the waste load to the municipality and reduce
sewer use surcharges. The solids removed by the vibrating screen and
rotary drum filter will be disposed of in a sanitary landfill.
The total anticipated effect of new technology utilized in sweet
potato processing as opposed to conventional technology is presented
in Table 5.
The economic implications of the water and waste reduction techniques
demonstrated will be determined for individual processes and for the
total plant. Budgeting procedures will be used to determine costs,
returns, and changes in net revenue due to the new technology.
Economic implications for devising water and waste reduction policies
will be determined from a comparative analysis of the cost of inplant
water and waste reduction and wastewater treatment costs.
96
-------
TABLE 5
Anticipated Effect of New Technology Utilization in
Sweet Potato Processing as Compared to the
Conventional "State of the Art"
Parameter
Product Yield
Water (gal/ton)
BOD (Ibs/ton)
COD (Ibs/ton)
Suspended Solids (Ibs/ton)
Total Solids (Ibs/ton)
Solid Waste (Ibs/ton)
Lye Consumption (gal/ton)
Conventional
Technology
40%
2600
60
140
30
160
200
9.2
Advanced
Technology
45-50 %
1400-1600
10-15
25-35
1-5
35-45
600-700
4-7
97
-------
Guides for water and wastewater management for the sweet potato pro-
cessing industry will be formulated. The results of this demonstration
grant can be used as management guidelines for applications of infrared
peeling, lye reconditioning, high pressure water systems, and pretreat-
ment in the sweet potato processing industry.
SUMMARY AND CONCLUSIONS
The conclusions that can be drawn from the first year of the demon-
stration grant on water and waste management in sweet potato pro-
cessing are:
1) The saleable product yield utilizing conventional
practices of sweet potato canning is 40 percent.
2) The rate of water consumption is 2,600 gallons per
ton of raw product input, or 91 gallons of water per
case of 2-1/2 cans produced.
3) Conventional sweet potato processing will produce
60 pounds BOD, 140 pounds COD, 160 pounds total solids,
and 30 pounds suspended solids per ton of input after
twenty-mesh screening.
4) If the sweet potato canning processors are to continue
to exist in North Carolina, steps must be taken to
increase product yield, lower peel loss, lower water
consumption, and significantly reduce the local impact
of the waste released from the plants.
98
-------
RBC TREATMENT OF SIMULATED POTATO PROCESSING WASTES
by
M. W. Cochrane and K. A. Dostal*
INTRODUCTION
This paper summarizes the observations made during the operation of
a pilot plant RBC** (Rotating Biological Contactor) for the treatment
of simulated potato processing wastes.
The RBC has not been used in the United States for treatment of potato
processing wastes, and this project was designed to establish at least
the feasibility of this type of treatment.
The objective of this report was to characterize the removal efficiency
of the RBC under various organic and hydraulic loadings and other variable
parameters independently, which dictated a simulated wastewater be used
that was representative of the large variety of potato processing plants.
The study was conducted at the Environmental Protection Agency's,
National Environmental Research Center (NERC), Corvallis, Oregon, by
members of the National Waste Treatment Research Program.
TREATMENT PLANT DESCRIPTION & OPERATION
The RBC consisted of circular discs mounted on a rotating shaft. As the
shaft rotated, the discs rotated, which caused the biological slime
on the discs to become submerged alternately in the wastewater and then
exposed to the air. In this way, the slime organisms obtained substrate,
nutrients, and oxygen which were necessary for aerobic treatment.
Continuous growth of new slime organisms and sloughing off of older
organisms caused a dynamic balance to be reached between organic removal
and sludge production. The sludge produced in the RBC must then be
separated from the liquid and be given further treatment.
The RBC used in this study had the following dimensions and operating
data:
Disc diameter 2 ft
Disc thickness 3/8 inch
Disc spacing 1-1/2 inch center to center
*Respectively, Sanitary Engineer and Chief, Food Waste Research Section,
National Waste Treatment Research Program, National Environmental Research
Center, Corvallis, Environmental Protection Agency, 200 S.W. 35th St.,
Corvallis, OR 97330
**Autotrol Corp., Milwaukee, Wisconsin.
99
-------
Disc material expanded polystyrene
No. of discs per stage 5
No. of stages 6
Specific surface area of discs 15 ft2/ft3
Disc rotation speed 10 rpm Run No. 1 and 2 and 20 rpm Run No. 3
Drive motor (chain drive) 1/10 hp Run No. 1 and 2 - 1/8 hp Run No. 3
Overall dimensions 63"(L)x25"(W)x28"(H)
Specific surface area was the total surface area of the discs divided
by the "shaft-length volume" occupied by the discs. The shaft length
was approximately 4 feet.
A photo of the RBC is shown in Figure 1.
Nutrient addition was considered necessary since analyses of influent
samples at the start of the project showed at times there was less nitrogen
and phosphorus than required to meet the generally accepted 100:5:1
(BOD:N:P) ratios.
Figure 2 is a flow diagram of the treatment plant. Concentrated potato
feed was pumped from cold storage (4°C) and joined with a dilution stream
of tap water before entering a primary clarifier where the surface settling
rate was always less than 300 gpd/ft2. Settled effluent from the primary
clarifier flowed by gravity to stage one of the RBC. A solution of
nitrogen and phosphorus nutrients was also pumped to the influent line.
Influent to the RBC in stage one took place at the water surface level
while flow between stages 1 and 2, 2 and 3, 4 and 5, and 5 and 6 occurred
3/4 inch, above the bottom of the baffles through a 1-1/2 inch diameter
hole. Flow from stage 3 to 4 took place through a 1 inch diameter hose
on the side of the unit 4-1/2 inches from the bottom. Effluent flow
occurred at 3 inches above the bottom through a 1 inch diameter opening.
Disc rotation was counterclockwise when looking from influent to effluent
end. Power for rotation was provided by an electric motor, variable
speed gear box, and chain drive.
Liquid level in the RBC was controlled at about 8 inches depth by the
liquid level control box which also provided a slight flushing action
which prevented clogging of the RBC effluent line and subsequent increase
in biological solids concentration in the RBC mixed liquor.
Hydraulic detention time studies were conducted using sodium chloride as
a tracer and an electrical conductivity meter. Two runs were made under
steady state conditions. The first run was at 0.61 gpd/ft2 hydraulic
rate, and the second was at 0.25 gpd/ft2. Both runs were made using a
clean RBC, i.e., no biological growth or wastewater was on the discs or in
the mixed liquor.
100
-------
ORE 1. RBC PILOT PLANT
itf
-------
-Tap Water
Sludge
Discharge
Nutrient Feed
Pump
Nutrient
Feed
Tank
Sample
Port '*
1*0 Hose
Elec.
Controls
Primary
Clarifier
Sample
Port
Liquid Level
Control
Box
\
Cone.
Feed
Pump
Cone.
Feed
Cold
Storage
Baffle with l0 Opening
at Bottom (Typical)
Solid Baffle
Sample
Cold
Storage
Sample
Port
DISCHARGE TO DRAIN
FIGURE 2. TREATMENT PLANT FLOW
DIAGRAM
102
-------
Microbiological examinations of the disc slime and mixed liquor were kept
general in nature. Daily notes were made of slime morphology. Microscopic
slides were examined periodically for relative quantities of broad groups
of microorganisms in the mixed liquor and disc slime. Photos were taken
of the RBC and microscopic slides at various times to record general
changes in relation to loading rates.
Influent and effluent samples were taken as either grab or composite
with the composite samples collected either automatically by gravity
sampler or on a periodic basis by hand over 18 to 24 hours.
Samples of influent usually were taken every day, Monday through Friday,
and effluent samples were collected on Tuesday, Wednesday, and Friday.
Effluent samples were taken from the sixth stage mixed liquor. Then,
the samples were placed in graduated cylinders and allowed to settle
for 3 hours. Supernatant samples were collected after 1 hour and 3
hours of settling. Sludge was collected only after 3 hours settling.
Table 1 lists the analyses performed.
Table 1. Influent and Effluent Analyses
Influent
pH
T-Alk
COD
COD(S)
BOD
BOD(S)
TOG
SOC
SS
VSS
TKN
NH3-N
Total-P
Effluent
(1 hr settling)
COD
SS
Effluent
(3 hr settling)
pH
T-Alk
COD
COD(S)
BOD
BOD(S)
TOC
SOC
SS
VSS
TKN
NH3-N
Total-P
(S) • soluble (filtrate from 0.45 y. membrane filter)
Mixed liquor samples from the third stage were settled in a graduated
cylinder, and the supernatant after 3 hours settling was analyzed
for turbidity. Settleability tests were run on both third and sixth
stage mixed liquors.
103
-------
Dissolved oxygen was measured in the first and sixth stage mixed
liquors with a YSI probe. Temperature was measured in the primary clarifier,
mixed liquor, and ambient air. Relative humidity and temperature
of the ambient air were recorded automatically on a continuous recorder.
RESULTS
Figure 3 presents the results of the tracer study of hydraulic detention
time. At 0.25 gpd/ft2 and 0.61 gpd/ft2 the theoretical hydraulic detention
time with 1/8 inch slime was calculated to be 17.1 and 6.3 hours, respectively.
From Figure 3 the corresponding values are 13.7 and 4.5 hours. No attempt
was made to correct detention time for the effect of biological solids in
the mixed liquor. The detention time in Figure 3 does not include primary
or secondary settling time.
The RBC was started by filling the mixed liquor tank with effluent
from a trickling filter at the Corvallis, Oregon, municipal wastewater
treatment plant. Batch feed with dilute synthetic potato waste was used
initially while effluent was recycled 100 percent to the influent end.
When slime began to appear on the discs, a steady feed rate was established
and recycle was discontinued.
Table 2 shows the average and range of influent and effluent parameters,
influent loading rates, and removal efficiencies.
TOC and SOC were run in addition to COD and BOD, but the results
were inconsistent for Runs //I and .#2 due to sample preservation
technique. Run #3 produced 80 to 90 percent removal of TOC and SOC.
The organic carbon loading rate (lbs/1000 ft2/day) was about 40
to 45 percent of the COD loading rate in Run #3 on a total and soluble
basis.
VSS removal paralleled SS with 95 to 100 percent of the SS being
volatile in both influent and effluent.
Table 2 shows values obtained for 3 hour settled samples, but
1 hour settled samples produced equivalent data for COD and SS removal.
Mixed liquor data are summarized in Table 3. The percent solids
data refer to 3 hour settled samples. One hour settled samples
produced about 20 to 50 percent greater volumes of wet solids during
Runs $1 and #2, but during Run $3, one hour and three hour samples
yielded about the same volumes of sludge. Sludge flotation during
Run y/3 even caused 1 hour sludge volumes to be less than 3 hour volumes
occasionally.
104
-------
25r
i520
o
I
LU
15
h-
i10
LU
h-
LU
Q 5
<
111
Temp. 20°C
Tracer Na Cl
Detention Time Through RBC only
Curve for clean disc
and clean water.
Estimated curve
iu
for ^ slime thickness.
0.20 0.40 0.60 Q80
HYDRAULIC RATE-GPD/FT2
1.00
FIGURE 3. MEAN HYDRAULIC DETENTION TIME.
105
-------
Table 2. Influent and Effluent Pat*.
Parameter
Station
Run No. 1
Run No. 2
Run No. 3
Parameter
Run No. 1
Run No. 2
Run No. 3
Parameter
Run No. 1
Run No. 2
Run No. 3
Parameter
Run No. 1
Run No. 2
Run No. 3
Parameter
Run No. 1
Run No. 2
Run No. 3
Parameter
Run No. 1
Run No. 2
Run No. 3
Parameter
Average
Inf
732
2337
2193
508
1688
1785
Eff
126
332
313
99
161
198
COD [ Total)
Range
Inf
671-828
1710-3100
1860-2510
BOD (Total)
200-635
1160-2280
1520-2190
Eff
57-218
207-519
174-472
70-115
125-230
115-457
Inf Ibs COD/1000 ft'/day
1.52
4.86
10.6
44
53
143
6.8
6.6
6.5
30.0
70.9
77.5
46
74
40
6.6
6.4
5.6
2.7
23.1
41.6
1.40-1.73
2.60-6.32
9.2 -12.3
T-Alk
12-82
14-129
16-407
pHt
6,8-6.8
6.3-6.9
6.0-6.6
NHi-N
28.9-31.0
63,0-81.0
73,0-82.0
BOD/COO
24-65
37-103
12-80
5.3-7.0
5.9-6.8
5.1-6.1
1.4-5.0
5.4-48.0
—
COO (Soluble)
Average
[nf
469
1675
1620
297
958
1370
Eff
64
142
196
53
60
74
Range
(nf
323-546
946-2610
1420-1840
BOD (Soluble)
391 -560
658-1330
1260-1480
Eff
40-136
58-205
113-303
51-55
25-110
66-82
Inf Ibs BOD/1000 ft'/dty
1.06
3.35
9,0
184
377
536
42.
100.
137
45.3
103.7
121.5
70
95
124
9 25.3
5 58.3
76.0
36.6
99.6
110.0
(Average)
Average
17.
23.
20.
4:1
6:1
5:1
0.42-1.33
2.50-4.20
7.48-10.8
SS
130-290
240-600
380-680
T-KN
35.6-44.9
90.5-107
133.0-140
Total •,?
44.0-47.0
91.0-116
118-125
Inf COD:N
40-100
34-180
90-160
18.7-33.1
44.4-81.0
76.0- -
28.0-46.0
79.8-110
110- --
(Range)
Range
16:1-19.7:1
16.7:1-33.9:1
18.2:1-22.8:1
* Removal (COO(S)
AverageRanae
Run No. 1 0.71 0.80 0.29-0.94 0.71-0.89
Run No. 2 0.74 0.66 0.67-0.82 0.46-0.7S
Run No. 3 0.78 0.63 0.71-0.86 0,58-0,68
Nutrient addition made before Inf Sampling Station
•Data 1n 1119/1 unless otherwise noted. Removals and loadings based on 3-hour settling. Inf 20°C
trtedUn Value
Run No. 1 - Av. 0.25 gpd/ft1 total hydraulic flow
Run No. 2 - Av. 0.25 gpd/ft2 total hydraulic flow
Run No. 3 - Av. 0.61 gpd/ft1 total hydraulic flow
91
95
91
81-95
93-96
88-94
» Removal BOD(S)
92 91-92
96 93-99
95 95-96
I Removal SS
54
73
76
17-86
50-93
67-80
I Removal T-KM
40
42
42
% Removal Total-P
19
Inf COO:!'
16.1:1 16:1-17.6:1
22.9:1 14.9:1-32:1
23.5:1 19.4:1-27.5:1
-------
Table 3. Mixed Liquor Data
RUN NO. 1
Parameter
D.O. (mg/1)
Temp. (°C)
pHt
SS (mg/1)
Solids*
First Stage
Average
4.4
16.5
6.8
Range
15.2-17.6
Sixth Stage
Average
7.0
14.6
523
48
Range
13.3-15.8
420-700
40-55
RUN NO. 2
Parameter
D.O. (mg/1)
Temp. (°C)
pHt
SS (mg/1)
Solids*
1.7
15.8
1.3-2.3
15.2-16.5
5.5
14.3
951
38
5.3-5.6
14.2-14.4
380-1160
7-63
RUN NO. 3
Parameter
D.O. (mg/1)
Temp. (°C)
pHt
SS (mg/1)
Solids*
2.0
16.3
1.0-2.5
15.3-17.5
4.4
14.5
5.7
1237
79
2.6-5.0
12.5-16.5
4.6-5.9
360-1970
66-91
fMedian value
*3-hr settling, % volume of sludge in 1000 ml glass cylinder.
107
-------
Percent solids for third stage mixed liquor averaged about the
same (for 1 hour and 3 hour samples) as the sixth stage samples.
Table 4 shows settled sludge data from 3 hour settled samples.
One hour settled samples were not taken for sludge analysis other than
for percent solids which is the same as the mixed liquor one hour sludge
volumes discussed above referring to Table 3.
The percent solids data in Table 4 should not be used as absolute
values for scale-up work. These values are intended to show only
relative amounts of wet sludge that would require pumping for further
treatment.
No attempt was made to show quantity of sludge synthesized because
of the need for a much more rigorous sampling program, which was beyond
the scope of this study.
Figure 4 presents the COD removal characteristics for the three
runs made during this study. The data shown were generated from three
hour settled samples with the result being Y = 0.93X.
COD applied is total influent COD and COD removed is total influent COD
minus soluble effluent COD.
The linear relationship shown in Figure 4 will undoubtedly discontinue
at some higher loading and the percent removal will begin to fall off. The
location of this breakpoint was not determined due to termination
of the project after three runs.
Figure 5 shows the average effluent concentration of soluble COD
during the organic loading rates covered in the study. The data represents
3 hour settled effluent, however, 1 hour settled effluent results were
essentially the same.
Figure 6 summarizes the suspended solids of settled effluent samples. The
lowest concentration obtained was 40 mg/1 which occurred during the lowest
loading rate. Data from 1 hour samples closely paralleled those from
the 3 hour samples.
An attempt was made to correlate COD removal efficiency and relative
numbers of microorganisms in the disc slime and mixed liquor, but the
results did not appear to be significant.
Figure 7 shows the typical appearance of the slime on stage 3 and 4 discs.
The slime was smoother and somewhat less patchy on stages 1 and 2 and
more patchy on stages 5 and 6. Slime color varied from cream to brown
from stages 1 to 6.
108
-------
Table 4. Settled Sludge Data*
Run No. 1
Run No. 2
Sun No. 3
Parameter
TS (rag/kg)
TVS (mg/kg)
Solids t
H TOG (mg/1)
o
BOD (mg/1)
COD (mg/1)
TKN (mg/1)
T-P (mg/1)
Average
1480
1220
48
168
482
1210
147
60
Range
885-2130
679-1840
40-55
96-239
226-650
682-2120
62-203
36-77
Average
3340
2680
38
872
1370
2790
367
165
Range
2160-6590
1660-5550
7-63
810-1180
1240-1600
1060-6780
174-560
110-220
Average
2890
2280
79
790
1310
2230
267
162
Range
1760-3800
1260-3180
66-91
365-1230
1140-1470
1050-3660
240-294
158-172
*3-hr settling In 1,000 ml glass cylinder
t % Volume of Sludge
-------
Q
\
•JL20
u.
0
o
-r 15
CO
CD
_J
LU
u 5
a:
o
o
o 0
Inf. Temp 20° C
Hydr. Rate 0.25-0.61 gpd/ft.2 /
Disc Rotation 10-20 rpm /
3-hr. Settled Eff. /
a
^
CJ3
/
> Y=0.93X
A
/*
?
-------
020
e**
U.
015
o
10
CO
DO
•^
I
O
UJ
o
So
Inf. Temp. 20°C
Hydr. Rate 0.25 -0.61 gpd /ft?
Disc Rotation IO-2Orpm ,
3-hr. Settled Eff.
50
100 150 200 250
SOLUBLE EFFLUENT COD-MG/L
FIGURE 5. SOLUBLE EFF. COD vs APPLIED COD
111
-------
CO
00
-J
I
Q
UJ
_J
Q.
Q.
Q
O
O
CVI
I-
U_
O
2 15
10
0
Inf. Temp 20° C
Hydr. Rate 0.25-0.61 gpd/fts
Disc Rotation 10-20rpm
3-hr. Settled Eff.
0
50 100 150
EFF. SS-MG/L
200
FIGURE 6. EFF. SS vs APPLIED COD
-------
FIGURE 7. DISC SLIME MORPHOLOGY
I
113
-------
When the slime sloughed off the discs, it became part of the mixed liquor
solids which had the appearance of billowing marabou feathers as presented
in Figure 8. The largest mass shown in the photo is about 3x5 inches.
Clumps twice that size were observed during the study.
Microscopic examination of mixed liquor and disc slime showed all trophic
levels of organisms, including worms and excluding mammals. However, the
structural components of the biomass were mostly filamentous bacteria
and fungi.
There were no appreciable odors from the RBC unit itself, but during
secondary clarification quite offensive odors were evident as a result
of anaerobic conditions.
CONCLUSIONS
Within the range of loadings of the study, the RBC proved to be an efficient
method of treatment for synthetic potato processing wastewater. However,
effluent COD and SS concentrations were higher than those generally
considered acceptable for discharge to receiving waters, and additional
treatment of the effluent may be required.
All the objectives of the project were not met due primarily to logistic
problems. The slime grew "full-scale" size under a "pilot-plant" size
project, which caused stoppages in lines and baffle openings and resulted
in unsteady state conditions. This problem would have become overwhelming
at loading rates beyond those used in the study.
ACKNOWLEDGMENTS
Appreciation goes to the following for their participation in this study:
Robert J. Burm, EPA, Denver, Colorado
R. Stewart Avery, EPA, Pacific Northwest Water
Laboratory, Corvallis, Oregon
Autotrol Corp., Milwaukee, Wisconsin
The R. T. French Co., Shelley, Idaho
114
-------
FIGURE 8. MIXED LIQUOR SLI>E
-------
TREATMENT OF SOY WHEY BY MEMBRANE PROCESSES
by
R.L. Goldsmith*, M. M. Stawiarski**, E.T. Wilhelm**,
and H. G. Keeler***
I. INTRODUCTION
The most rapidly growing and commercially attractive area in
soybean processing involves the production of protein concen-
trates and isolates, products containing from 70 to 95% protein.
Although manufacture of these products utilizes only a small
percentage of the total soybean crop, processing operations
generate a large proportion of the total BOD present in a soy-
bean processing plant effluent.
Purification of soy protein from defatted soy flake involves
a series of operations (Figure 1). Following extraction with
dilute alkali and removal of insoluble solids, proteins are
precipitated as a curd by acidification. Different acids are
used for edible and industrial grade products. The curd is
removed as the desired purified protein product by filtration
or centrifugation, and the resultant liquid phase is discarded
as waste. This soy whey contains a significant quantity of
protein together with carbohydrates (mainly sugars) and some
salts. The proteins and the carbohydrates together give the
soy whey effluent a variable BOD5 depending on the operating
conditions used in the precipitation step, the time in the pro-
cess cycle, and the amount of washing performed.
The soy whey proteins are functionally and nutritionally valuable
because of their excellent solubility and because'they contain
a greater proportion of some essential amino acids (such as
* Abcor, Inc., Cambridge, Massachusetts
** Central Soya/Chemurgy Division, Chicago, Illinois
*** Environmental Protection Agency, Washington, D.C.
117
-------
DILUTE _
ALKALF^"
DEFATTED
SOY
FLAKES
•^NJT
EXTRACTION
SOLIDS
SEPARATION
•w-
ACID
H,
SOLIDS
SEPARATION
,_^_ SOY
"^" WHEY
CO
UNDISSOLVED
SOLIDS
PROTEIN
PRODUCT
FIGURE 1
SOY PROTEIN PROCESS FLOW - SOURCE OF SOY WHEY
-------
methionine) than the precipitated fraction. If these proteins
can be recovered in undenatured form,they will be at least as
Valuable as those in the isolate or concentrate now being
produced. The loss of the soluble whey proteins and carbo-
hydrates not only results in a water pollution problem, but
also represents an economic penalty against the process because
otherwise usable materials are being discarded.
Typical composition of soy whey on both a wet and dry basis
is given in Table I.
TABLE I
SOY WHEY COMPOSITION
I. Wet Basis
Total Solids, % 1.5%
Total soluble solids, % 1.4%
Apparent Protein (Nx6.25),% 0.3%
True Protein, % 0.18%
BOD, mg/1 7,700
COD, mg/1 15,200
pH 4.6
II. Dry Basis
True Protein (Nx6.25), % 12.0
Sugars 45.0
Sucrose, % 24.7
Stachyose, % 16.6
Raffinose, % 3.7
Minerals, % 23.0
Amino Acids, Peptides,
other organics, % 20.0
100.0%
119
-------
The nature of proteins and sugars from both the edible and
industrial protein processes are quite similar and after
purification and recovery they should be valuable as process
byproducts. In addition, treatment of soy whey by membrane
processes, as detailed below, will substantially eliminate the
water pollution problem since BOD contaminates will be removed
from the final effluent.
Figure 2 shows a simplified flow schematic for the two-step
membrane process for soy whey treatment. Operation is almost
identical to that used commercially for the treatment of cheese
wheys (l/2_) . In the present case soy whey, with or without
filtration for fines removal, is introduced into a low pressure
ultrafiltration unit (UF) (step 1). In this operation, whey
is concentrated 20 to 40-fold by volume. The ultrafiltration
membranes retain only the whey proteins. Thus, it is possible
to obtain a protein concentrate with a higher proportion of
proteins in the dissolved solids, since sugars, non-protein
nitrogen, minerals and other solutes pass through the membrane.
Operation is typically in the pressure range of 10 to 100 psi,
and at temperatures of 100 to 130°F. The true protein content
of raw whey can be increased from an initial value of about
0.2% up to levels exceeding 8% in this step. Simultaneously,
the proportion of protein in the whey solids can be increased
from approximately 12% to 80% in a one-step concentration (that
is, without redilution with water and reconcentration).
The permeate (ultrafiltrate) from the UF unit is introduced into
a second membrane step. In a reverse osmosis (RO) operation,
this stream is concentrated from approximately 1.0% solids to
10% solids or more. Typical operating pressures are 500 to
1500 psi; and temperatures, 70 to 100°F. The membrane in the
120
-------
SOY WHEY
PROTEIN CONCENTRATE
STEP 1
UF
10 - 100 PSIG
H20, SUGARS
NON-PROTEIN N,
MINERALS
LOW M,W, SOLUTES
SUGAR CONCENTRATE
STEP 2
RO
> 500 PSIG
LOW BOD WATER
FIGURE 2
MEMBRANE PROCESS FOR SOY WHEY TREATMENT - FLOW SCHEMATIC
-------
RO section is chosen to retain as great a proportion of the
organic solutes as possible, thereby resulting in a low BOD
permeate. The final effluent from the RO section can either
be reused within the plant or discharged. Depending on
pollution control regulations, a membrane with moderate salt
rejection can be used in the RO section to permit partial
desalting of the concentrate. In general, from the point of
view of pollution control, this option will probably not be
exercised.
The membrane test data presented below were obtained under a
grant from the Office of Research and Monitoring of the
Environmental Protection Agency to the Chemurgy Division of
Central Soya, Chicago, Illinois, (Grant No. 12060 FUR). The
preliminary data were obtained with tubular membrane units
installed at Abcor, Inc. More recently a pilot plant has been
operated at Central Soya's Chicago plant to confirm laboratory
data, and pilot data are also reported. Pilot operation has
been underway since mid-1971.
122
-------
II. EQUIPMENT AND EXPERIMENTAL PROCEDURES
A. Laboratory Tests
Ultrafiltration and reverse osmosis tests were initially per-
formed at Abcor, Inc., in bench-scale equipment.
The Ultrafiltration unit contained 15 ft2 HFA-180 tubular mem-
branes, and was used to concentrate samples of edible grade
whey shipped frozen from Central Soya's Chicago plant. A flow
schematic is shown in Figure 3. Whey was charged to a 50 gallon
feed tank and heated to 125°F. While processing the whey, its
temperature was maintained at this level by passing hot (or cold)
water through a coil installed in the tank. Water flow was
controlled by a solenoid valve, actuated by a temperature switch
installed in the tank.
Whey was recirculated through the tubular membranes with a 2 hp
centrifugal pump. The system recirculation rate was measured
with a rotameter, and controlled by means of two globe valves.
These valves were also effective for controlling the system
operating pressure; membrane system inlet and outlet pressures
were measured. Fractional water removal per pass through the
membranes was very small (typically less than 0.001), and
"conversion-per-pass" was negligible. Correspondingly, the
system contents were well-mixed.
For batch concentration experiments permeate was withdrawn
continuously while the concentrated feed was removed only at the
end of the test by draining the system. During batch concen-
tration additional feed was charged to the reservoir to allow
processing feed volumes exceeding 50 gallons.
123
-------
TEMPERATURE
HOT H20
FEED TANK
COIL
o
ct
PUMP
ROTAMETER
MEMBRANES
PERMEATE
(TO STORAG
E;
FIGURE 3
LABORATORY TEST SYSTEM FLOW SCHEMATIC
-------
In the same system differential experiments were performed.
In these, permeate was returned continuously to the feed tank.
This allowed tests to proceed with time-invariant feed concen-
tration and composition.
Batch concentration experiments were employed to determine the
dependence of membrane flux and retention on feed concentration,
Tests of this nature were generally carried out at a fixed
temperature, feed circulation rate and pressure. Differential
experiments examined the effects of time, temperature, and
pressure on membrane performance.
The reverse osmosis test system was similar in layout to that
of the ultrafiltration system. Major differences include the
use of a different pump, valves and piping, since operation
was at substantially higher pressures. Experiments were of
two types, "differential" and "batch concentration". Abcor
TM5-14 tubular membrane modules with turbulence promoters
were used. Measured salt rejection prior to tests was 96%
(80°F, 650 psi, 0.5% NaCl feed). All experiments described
below involved processing of permeate collected from batch-
concentration ultrafiltration experiments.
B. Pilot Tests
Following completion of laboratory tests, a nominal 1000 gpd
pilot unit was built and installed at Central Soya's Chicago
facility. Flow schematics are shown in Figures 4 and 5.
Soy whey (125 - 130°F) is piped directly from the protein pro-
duction plant to a 500 gallon feed surge tank. Whey is drawn
from the tank and pumped through a 3-stage ultrafiltration unit,
Each stage is recirculated, allowing the maintenance of high
125
-------
SOY WHEY FROM
PROTEIN PLANT
500 GAL
SURGE
TANK
LOW LEVEL
SHUT OFF
RECIRCULATION
LOOP
PRESSURE
CONTROL
VALVE
LEGEND
T - TEMPERATURE INDICATOR
P - PRESSURE INDICATOR
PS - LOW PRESSURE CUTOFF SWITCH
FLOW
CONTROL
VALVE
RECIRCULATION
LOOP
RECIRCULATION
LOOP
PERMEATE TO
RO SECTION
CONCENTRATE
FIGURE
ULTRAFILTRATION SECTION
-------
NJ
r
PERMEATE FROM
ULTRAFILTRATION
SECTION
100 GALC
SURGE
TANK ,
HIGH LEVEL CONTROL
LOW LEVEL CONTROL
COLD WATER
•N
s
PRV
fr*
HEAT
EXCHANGER
HIGH PRESSURE
PUMP
LEfiEHD.
TS - TEMPERATURE SWITCH
T - TEMPERATURE INDICATOR
PRV - PRESSURE RELIEF VALVE
P - PRESSURE INDICATOR
TEN ABCOR TM 5-14 MODULES
CONCENTRATE
FLOW
MEASUREMENT
FLOW
CONTROL
VALVE
PERMEATE .
(FLOW MEASUREMENT)
PERMEATE
FIGURE 5
REVERSE OSMOSIS SECTION
-------
feed velocity through the tubular membranes, but still enabling
operation to proceed with high fractional water removal, or
high "conversion". The system can be operated on a once-
through basis, with concentrate removed continuously from
stage 3, or in a batch mode by allowing a high "bleed" flow
from stage 3 to be recycled to the feed surge tank.
An Abcor UF-22S pilot plant is used for each stage. Each unit,
containing 22 ft membrane area, is fitted with a calibrated,
variable speed, positive-displacement pump to vary, control and
measure recirculation rate. Other monitors and instruments
measure and control temperature and pressure. The units are
fitted with safety devices (conductivity switch, pressure switch,
temperature switch) to permit unattended operation.
The permeates from the three stages are fed to a 100 gallon
interstage surge tank (Figure 5). Feed to the reverse osmosis
system is cooled from the ultrafiltration operating temperature
to below 100°F. Due to mechanical strength considerations, the
reverse osmosis equipment must be operated at temperatures
below this level. Temperature is controlled by an in-line
temperature switch (TS), which activates cooling water flow
to a heat exchanger. The actual temperature is measured and
transmitted to a meter on the control panel.
A high-pressure, positive displacement pump introduces the feed
into a series of Abcor TM 5-14 modules equipped with turbulence
promoters. Six to ten modules can be tested at one time. Oper-
ation is "once-through", A pressure relief valve on the pump
outlet controls membrane inlet pressure. Inlet and outlet
pressures and the total permeate flow are measured. Downstream
flow is measured,and controlled with a flow control valve.
128
-------
A photograph of the pilot system on site is shown in Figure 6.
Other membrane modules manufactured by Westinghouse, DeDansk
Sukkerfabrikker, and Gulf Environmental Systems are also under
evaluation. Results reported here were obtained with the Abcor
system.
129
-------
FIGURE 6
PHOTOGRAPH OF PILOT PLANT INSTALLATION
-------
III. ULTRAFILTRATION DATA
A. Dependence of Flux on Time
Membrane fouling has been encountered in both laboratory and
pilot tests, as evidenced in flux decay with time. Figure 7
shows data for flux decline over a 24 hour period. These data
are for differential operation; that is, feed whey solids and
protein contents are essentially unchanged.
In properly cleaned systems, initial flux levels are 25 to 35
9\
gfd (gal/f tvday), dropping substantially during the initial
10 hours. With unfiltered whey, laboratory data have exhibited
higher values than the pilot unit. This has been true especially
when the pilot unit was incompletely cleaned before a test.
Whey filtration with a pilot-scale precoat filter resulted
in a substantial reduction in flux decline for the pilot plant;
the flux level observed was more nearly comparable to laboratory
data. Whether or not this will be a preferred process step
depends on several factors:
a. The increase in process costs for a filtration
step compared with cost reduction for the ultra-
filtration step;
b. Loss of recoverable protein in the filtration step; and
c. Relative value of recovered whey protein with and
without suspended and colloidal solids removal.
Fouling and the accompanying flux decline are not completely
understood, but the following factors are known to be important.
1. Suspended and colloidal materials contain a "foulant"
which coats the membrane surface, reducing flux.
131
-------
S 30
X
_l
11.
UJ
<
o:
01
z:
20
10
5 10 15 20
OPERATING TIME, HOURS
EDIBLE GRADE SOY WHEY
1" DIAMETER TUBULAR HFA-180
MEMBRANES
20 GPM FLOW/ 10 PSI
A PRELIMINARY LABORATORY DATA (125top)
O PILOT DATA IN WELL-CLEANED SYSTEM
(INITIALLY 120°F, DROPPING TO 105°F)
D LOW FLUX PILOT DATA (120°F)
• PILOT DATA WITH FILTERED WHEY (115°F)
FIGURE 7: ULTRAFILTRATION FLUX AS A FUNCTION OF TIME
132
-------
Filtration partially removes the foulant and the
flux decline problem is relieved substantially.
Also, fouling appears to be less severe when a
small batch of whey is recirculated within the
unit than when fresh whey is continuously fed to
the unit. This suggests that the whey contains
a material adsorbed by the membrane surface, and
that maximum fouling occurs when the highest amount
of foulant is processed per unit membrane area.
2. Microbiological growth, accompanied by whey acid-
ification, results in a rapid flux decline. Tur-
bidity develops in the whey under these conditions,
as expected, since additional dissolved protein is
precipitated. Addition of preservatives, such as
hydrogen peroxide, inhibits bacterial growth and
acidification, and reduces flux decay.
3. When the membranes are not completely cleaned be-
for a test, fouling is especially severe.
In general,no correlation is exhibited between fouling and
operating temperature, pressure and feed circulation rate.
Reasons for the difference between laboratory data and pilot
plant performance are not clearly understood. Changes in
processing conditions in the protein plant which occurred between
laboratory tests and the initiation of pilot studies are suspect.
These may have changed the nature of the whey. There were no
apparent differences in membrane properties; replacement of some
of the membranes in the pilot unit by ones used in the laboratory
did not result in improved performance.
133
-------
We are currently trying to determine the optimum means of
maintaining high flux levels. High, stable fluxes will reduce
the membrane area requirement for a full-scale plant and
minimize down-time for system cleanup. Both are obviously
desirable from the point of view of process costs.
B. Dependence of Flux on Feed Concentration
Flux data for laboratory and pilot plant tests as a function of
feed concentration are shown in Figure 8. The laboratory test
with raw whey and pilot tests with raw and filtered whey were
performed as batch concentrations. Thus, in all three there
were high fluxes at low concentrations during the initital
part of the test. Operating times for the tests are given in
Tables II, III, and IV.
Although time and temperature play important roles, higher fluxes
were experienced in the laboratory than in the pilot plant. For
all tests, flux declined with feed concentration. Similar flux
behavior has been observed in the ultrafiltration of cheese
wheys (1,2)
C. Retention Data
Figure 9 shows the dependence of retention* of both protein and
total solids on feed concentration. Retentions for both increase
with increasing feed concentration, since at higher concentrations
a greater proportion of the solutes consist of higher molecular
weight materials. Protein retention is always less than 100%
*
Retention is defined as: C- , - C
wfeed
134
-------
H
W
Ul
30
FLUX, GFD 20
10
0,1
O LABORATORY DATA/ UNFILTERED WHEY
(SEE TABLE II)
A PILOT DATA/ FILTERED WHEY (SEE TABLE iv)
D PILOT DATA. UNFILTERED WHEY (SEE TABLE III
1 10
RETAINED FEED SOLIDS (CFEED - CpERMEATE), %
FIGURE 8
100
DEPENDENCE OF FLUX ON FEED CONCENTRATION
-------
TABLE II
LABORATORY TEST WITH UNFILTERED SOY V7HEY
(Operating Conditions: 20 gpm, 40 psig)
Operating
Time
Hours
0.10
0.35
2.33
6.72
9.48
10.23
10.85
11.30
11.70
11.95
Temperature
70
82
122
122
124
125
126
126
126
133
Flux
gfd
31.2
26.5
23.0
21.8
19.1
15.8
11.9
9.0
6.6
6.3
Feed
Solids
1.30
1..38
1.63
1.99
3.25
4.39
6.04
7.86
9.94
12.03
Feed
Protein
0.27
0.30
0.44
0.63
1.55
2.40
3.42
5.08
6.63
7.85
-------
TABLE III
PILOT TEST WITH UNPILTERED SOY WKEY
(Operating Conditions: about 20 gpm, 40 psig)
Operating
Time
Hours
0.5
1.0
1.5
2.5
3.5
4.5
5.5
8.5
13.5
22.5
26.5
0.5
1.0
1.5
2.5
3.5
4.5
5.5
8.5
13.5
22.5
26.5
0.5
1.0
1.5
2.5
3.5
4.5
5.5
8.5
13.5
22.5
26.5
Temperature
OF
119
120
120
119
118
118
115
110
105
90
104
115
121
122
121
120
120
118
114
108
94
110
100
112
116
116
116
116
114
109
104
93
108
Flux
gfd
STAGE 1
25.1
22.9
21.3
19.8
19.2
17.4
16.4
13.0
11.0
9.5
8.7
STAGE 2
20.2
19.1
18.0
16.0
14.9
13.6
12.8
11.0
9.2
7.6
6.5
STAGE 3
20.7
18.5
18.0
16.2
14.7
13.1
12.0
10.0
8.5
6.5
3.8
Feed
Solids
1.22
1-27
2.37
4.96
1.28
1.46
2.73
5.75
1.25
1.72
3.15
6.39
Feed
Protein
0.35
0.37
1.15
3.39
0.35
0.50
1.35
3.92
0.52
0,70
1.65
4.47
137
-------
OO
TABLE IV
PILOT TEST WITH FILTERED SOY WHEY
(Stage 1 only)
(Operating Conditions: approx. 20 gpm, 35 psig)
Operating
Time
Hours
0.1
1.0
4.25
4.75
5.25
6.33
Temperature
op
107
114
114
114
114
114
Flux
gfd
37.5
28.4
14.1
13.0
11.7
7.0
Feed
Solids
%
1.30
1.90
2.13
2.48
5.3
Feed
Protein
%
0.25
0.72
0.90
1.22
3.3
-------
100
90
80
70
| 60
UJ
50
30
20
PROTEIN
TOTAL SOLIDS
0 2 4 6 8 10 12
FEED CONCENTRATION, %
FIGURE 9
LABORATORY ULTRAFILTRATION RETENTION DATA
(EDIBLE GRADE SOY WHEY AS FEED)
139
-------
because the protein assay is sensitive to lower molecular weight
polypeptides and amino acids which pass through the membrane.
Gel permeation chromotography experiments have demonstrated that
"true" protein retention exceeds 98%.
Since protein retention - exceeds total solids retention the
protein composition of the feed solids increases with con-
centration. This is shown by the data of Figure 10, for both
laboratory and pilot data. Protein concentration and
composition is presented as a function of feed solids in the
concentrate. Laboratory and pilot data generally agree, with
the exception that pilot experiments produced products with
somewhat higher protein contents (~80%). Filtration made little
difference, since solids removed by filtration were comprised
of protein and non-protein materials.
Figures 11 and 12 show material balances for representative
laboratory (unfiltered whey) and pilot (filtered whey) tests.
140
-------
10
8
FEED PROTEIN, 6
O LABORATORY DATA
PI LOT DATA* UNFILTERED WHEY
PI LOT DATA, FILTERED WHEY
100%
80%
60%
20%
5 10
FEED SOLIDS, %
15
FEED PROTEIIU
(DRY BASIS)
FIGURE 10
COMPOSITION OF PROTEIN CONCENTRATES
(FILLED SYMBOLS ARE COMPOSITION; EMPTY SYMBOLS ARE CONCENTRATION)
-------
N>
TOTAL
FEED WHEY
100 LBS
TOTAL
SOLIDS
1,36%
PROTEIN
(Nx6,25)
,31%
\
I
TOTAL
PERMEATE
97,2 IBS
TOTAL
SOLIDS
1,05%
PROTEIN
(Nx6,25)
,10%
ULTRAFILTRATION
UNIT
TOTAL
CONCEN-
TRATE
2.8 IBS
TOTAL
SOLIDS
12,0%
PROTEIN
(Nx6,25)
7.80%
FIGURE
LABORATORY CONCENTRATION OF SOY WHEY BY ULTRAFILTRATION - MATERIAL BALANCE
-------
•e-
u>
TOTAL
FEED
WHEY
100 IBS
TOTAL
SOLIDS
1,33%
TOTAL
PERMEATE
95,1 LBS
TOTAL
CONCENTRATE
4,5 LBS
PROTEIN
0,281%
TOTAL
SOLIDS
1,05%
TOTAL
SOLIDS
5,3%
FILTER
PROTEIN
0,102%
PROTEIN
5,3%
FILTRATE
99,4 LBS
TOTAL
SOLIDS
1,27%
PROTEIN
0,247%
SOLIDS
0,06 LBS
PROTEIN
0,034 LI
UF
FIGURE 12
PILOT PLANT CONCENTRATION OF SOY WHEY BY ULTRAFILTRATION - MATERIAL BALANCE
-------
IV. REVERSE OSMOSIS DATA
Typical laboratory data for concentration of soy whey permeate
are presented in Figures 13, 14, and 15. The dependence of
flux on feed concentration is shown in Figure 13, and it is
apparent that concentrates exceeding 10% solids can be pro-
duced at 600 psi. Other experiments at higher pressures have
generated concentrates with solids levels exceeding 20%.
Figure 14 shows solids retention observed with the AS-197
membranes. COD or BOD retention is approximately the same,
as reflected in the material balance data of Figure 15.
These data have been confirmed in the pilot plant. Tabulated
data, covering a six-month period of intermittant operation,
are given in Table V. These test data were selected to
illustrate several points. First, flux is strongly dependent
on the degree of concentration achieved in the once-through
system. Flux dropped from 10 gfd for about 1.5-fold concen-
tration to 2.1 gfd for about 15-fold concentration. The
flux level, and its decline with increasing conversion, are
similar to laboratory data, as seen by reference to Figure 13.
Total solids, BOD and COD retentions were good, as demon-
strated by comparing the feed and permeate compositions of
Table V. Finally, during pilot plant operation there has been
no substantial change in flux or rejection efficiency of the
reverse osmosis system. Other data, not reported here, further
confirm this-conclusion.
144
-------
12
10
8
to
%
X
0
2 3 4 56789 10
FEED SOLIDS, %
FIGURE 13
LABORATORY REVERSE OSMOSIS DATA
DEPENDENCE OF FLUX ON FEED SOLIDS CONCENTRATION
SOY WHEY - UF PERMEATE AS FEED
OPERATING CONDITIONS: 600 PSI AND 25°c
145
-------
&>e
g
00
Q
100
99
98
97
0,3
CO
S 0,2
_i
CD
CO
S
•* 0,1
0
216
FEED SOLIDS, J
8
10
FIGURE
LABORATORY REVERSE OSMOSIS DATA - SOLIDS RETENTION
(SOY WHEY - UF PERMEATE AS FEED)
(OPERATING CONDITIONS SAME AS FIGURE 13)
146
-------
FEED (ULTRAFILTRATION PERMEATE)
TOTAL
FEED
100 LBS
TOTAL
SOLIDS
1,255%
COD
PPM
9900
^x, REVERSE OSMOSIS
^ ^ ^ UNIT
X.
TOTAL
PERMEATE
85,2 LBS
TOTAL
SOLIDS
,04%
COD
PPM
350
>_
•
TOTAL
CONCEN-
TRATE
14,8 IBS
TOTAL
SOLIDS
9,35%
COD
PPM
75,500
FIGURE 15
CONCENTRATION OF SOY WHEY/UF PERMEATE BY REVERSE OSMOSIS - MATERIAL BALANCE
-------
TABLE V
PILOT PLANT REVERSE OSMOSIS DATA
EFFECT OF CONVERSION ON PERFORMANCE
FEED
CONCENTRATE
PERMEATE
*-
00
DATE
7/26/71
2/10/72
8/9/71
11/24/71
FLUX/
GFD
10
5,5
4,4
2,1
OPERATING
PRESSURE/
PS I
600
720
660
710
TOTAL
SOLIDS/
7o
0,86
0,86
0,93
0,99
BOD/
PPM
5250
4150
3850
4300
COD/
PPM
8/236
10/000
9/790
9/600
TOTAL
SOLIDS/
1,31
3,00
8,53
12,74
. BOD/
PPM
8/000
15/200
35/300
62/000
COD/
PPM
12/600
27/200
90/000
140/000
TOTAL
SOLIDS/
%
0,02
0,07
0,04
0,21
BOD/ COH/
PPM PPM
86 192
250 540
165 414
1060 1840
-------
V. CONTINUING WORK
From these data it is apparent that soy whey can be treated in a
two-step membrane process to produce protein and sugar concentrates
as by-products, as well as a final effluent with greatly reduced
oxygen demand. The economic potential of the process is presently
under evaluation. The pilot data serve as design bases for costing
a full-scale installation. Attractiveness of the process depends
on by-product values, which also are presently under investigation.
VI. ACKNOWLEDGEMENTS
The authors acknowledge the financial support provided by the
Office of Research and Monitoring of EPA in Grant No. 12060 FUR.
Mr. Clifford Risley and Dr. David Rickles of the Chicago Office of
EPA have contributed to the direction and planning of this program.
VII. REFERENCES
1. "Membrane Processing of Cottage Cheese Whey for Pollution
Abatement", in Proceedings, Second National Symposium on
Food Processing Wastes; March 23-26, 1971; EPA Report
# 12060 FUR 03/71; pages 413 to 446.
2. "Industrial Ultrafiltration", in Membrane Processes In Industry
and Biomedicine; Plenum Press, 1971, pages 267-300.
149
-------
FULL-SCALE ANAEROBIC TRICKLING FILTER EVALUATION
by
Dennis W. Taylor*
INTRODUCTION
For the past 15 months the Food Waste Research Section of the National
Waste Treatment Research Program, NERC, Corvallis, has monitored
the operation of a unique industrial waste treatment system. This "in-
house" project was initiated through the cooperation of Centennial Mills
wheat starch-gluten plant in Spokane, Washington, and the U. S. Environmental
Protection Agency.
ANAEROBIC WASTE STABILIZATION
An anaerobic filter is basically a rock-filled enclosure where, in the
absence of oxygen, anaerobic organisms utilize organic wastes by convert-
ing them principally to methane, carbon dioxide, and water. The distribu-
tion header for the filter is usually located at the bottom, thereby creating
an upward flow through the submerged bed of rocks. Very little of the
organic matter stabilized is converted to new cells, thus the sludge disposal
problem (inherent in aerobic systems) is minimized.
Anaerobic treatment of biodegradable organics is essentially a two-step
process. In the first step complex organic materials are converted into
simpler organics, primarily fatty acids. Although no waste stabilization
occurs during this first stage, it is an essential step in anaerobic digestion,
The second step is carried out by a group of bacteria called methane formers.
These organisms are more sensitive to environmental insult than acid-forming
bacteria and require a number of favorable conditions to function properly.
Among the more important of these conditions are pH and temperature.
The primary products of the anaerobic degradation of organics are: gases
methane, 70 percent, and carbon dioxide, 20 percent; solids, new cells
<0.2 Ib/lb COD removed.
Perhaps the most significant advantage of anaerobic treatment involves
biomass production. Since the major portion of the waste is converted
to methane gas and carbon dioxide only a small amount of waste biological
sludge is produced. This markedly reduces the sludge stabilization
and disposal problem inherent in an aerobic system. This and other
advantages are listed in Table 1.
*Sanitary Engineer, Food Waste Research Section, National Waste Treatment
Research Program, U. S. Environmental Protection Agency, National Environ-
mental Research Center, 200 S.W. 35th St., Corvallis, Oregon 97330.
151
-------
Table 1. Advantages of Anaerobic Treatment
1. Low production of biological sludge
2. High treatment efficiency
3. Low capital cost
4. No oxygen requirement
5. Methane production (potential source of fuel)
6. Low nutrient requirement
7. Low operating costs
8. Minimal attention required (anaerobic filter)
9. Inherent long solids retention time (anaerobic filter)
The disadvantages of anaerobic treatment of concentrated soluble wastes
are relatively few. Three of the more important disadvantages are possible
production of malodorous gases, comparatively high operating temperatures,
and the system's slow acclimation to environmental changes (e.g., temperature,
loading).
WASTE TREATMENT FACILITY
The waste treatment facility at Centennial Mills was designed by Cornell,
Rowland, Hayes, and Merryfield of Corvallis, Oregon. Total cost of this
system, which incorporated some existing equipment, was in the neighborhood
of $110,000.
Figure 1 depicts the flow pattern of the facility. As can be seen,
in this diagram, the starch plant waste stream is introduced to the
system in the mix tank. At this location chemical addition and steam
injection are used for pH and temperature control, respectively. From
this tank automatic level controls activate pumps which feed the waste
to three anaerobic filters in parallel. The filters are rock-filled,
wood stave tanks 30 feet in diameter and 20 feet in height. The crushed
rock has a size distribution of 2 to 3 inches in the bottom half and
1 to 2 inches in the top half. From the collection header atop the
filters the treated waste can be recycled at rates from 0 to 100 percent
by simple adjustment of sliding flow diverters. That portion which
is not recycled enters a 4000 gallon chlorine contact tank. The chlorine
is introduced for odor control and sewer protection from H2S.
A cross-sectional view of the anaerobic filter tank is shown in Figure
2 while the distribution and collection headers are diagrammed in Figures
3 and 4. For a profile analysis of the wastewater, samples are withdrawn
from the taps shown in Figure 3. The requirement for uniform waste
application (to reduce short-circuiting) is exemplified in Figure 3
where it is shown that within one quarter-section of the distribution
header, forty-three 1/4 inch holes introduce waste to the filter. Figure
4 depicts the positioning of the collection header ports.
152
-------
RAW _
WASTE
CHEMICAL
". t
MIX
TANK
STEAM
LO
H
FLOW
DJVEKTCR
1 I
CHLORINE
COMTACT
TANK
CITV
SEWER
COLLECTION
HCADCR
H£ADC*
WASTE 6AS
BURNER
FIGURE I
ANAEROBIC FILTER. TftBATMENT
SYSTEM
CFNTENNIAi. MILLS
10-71
-------
COLLECTION
SAMPL£
Ul
•r— •«•
WOOD STAVf TANK
IOO.OOO &AL.
ROCK size : TOP i-z"
BOTTOM z
DISTRIBUTION
GAS
f COLLECTION
V
20
30'
D/AMETfR
FIGURE 2
ANAEROBIC FILTER CROSS-SECTION
-------
Ul
Ui
REDWOOD
f"~ ^ *
TAM
FLOC
SECTION A
{/4 ' HOLES
FIGURE 3
DISTRIBUTION HEADER
-------
FIGURE 4
COLLECTION HEADER
-------
No attempt is made to recover the energy available from the methane
gas produced. The gas, estimated at 30,000 cubic feet per day, is burned.
Following completion of construction in January 1971 the anaerobic
filters were filled with water, heated (85°F) and 2500 gallons of screened
anaerobic sludge were then added to each filter.
The startup waste-acclimatization period lasted approximately 45 days
after which time the treatment facility was accepting the entire waste flow.
During this period sodium bicarbonate was added to maintain pH level and
sufficient alkalinity. Nitrogen was also added to the system first in
the form of anhydrous ammonia then as pelletized urea.
Normal^operation consisted of no recirculation during the week and
100 percent recirculation when the starch plant was shut down for weekends
or for repairs. Chemical addition rates were 42 Ibs/hr for sodium bicarbonate
and 30 Ibs/hr for urea.
At one point the starch plant shut down operations for approximately
30 days. The filter pumps were turned off so that no recirculation
occurred during this resting period. To determine the ability of the
anaerobic filter to function efficiently after prolonged resting periods,
the entire waste flow was sent to them upon plant startup. Within three
hours the waste gas burner was in full operation and removal efficiencies
approximated those existing prior to the plant shut down.
Some overflows of the mix tank occurred due to the foamy nature of the
heated and agitated starch plant waste. The filter pumps were automatically
activated by contact probes located within the mix tank. Until these
probes were encased in a stand pipe and washed continually with a fine
water spray problems occurred.
Gas leakage from the wood stave filter tanks was cured by additional
sealing of the tank tops.
Anhydrous ammonia originally used as a nutrient (nitrogen) source had
to be replaced when a hard precipitate built up within the filter pumps.
The scale developed to a degree requiring shutdown for cleaning. After
replacing the liquid ammonia with urea the precipitate vanished.
Removal efficiency dropped markedly during a short period when the filters
were apparently overloaded. Due to the combination of excessive load
and a breakdown of the NaHC03 buffering system the pH of the filter
effluents dropped below 6.0 for six days. The pH level was as low as
4.8 during this period. Reducing the loading and adding excess NaHCOs
caused the pH level to climb back to near neutral. At this time removal
efficiencies were back to normal.
Malodorous conditions were prevalent during the initial phases of operation.
Until the tanks were adequately sealed and the gas burner properly adjusted,
a characteristic H2S odor was present.
157
-------
Table 2 lists the various volumes and loadings associated with this
system. The loading of 237 Ib COD/1000 cu ft/day is higher than the
normal loading rates of either the activated sludge or trickling filter
systems.
Although solids retention time, SRT, (total weight of suspended
solids within system T weight suspended solids leaving system per day)
is an important parameter for design and control of anaerobic systems
there exists no simple mode for its determination for anaerobic filters,
SRT's of up to 100 days or more are commonly reported in the literature
These figures are derived from laboratory scale models.
(1)
Table 2. Anaerobic Filter Volumes & Loadings
Total Filter Volume (3 filters)
Total Voids Volume (estimate)
Total Flow
Hydraulic Detention Time (theoretical)
Filter Temperature
Chemical Oxygen Demand
Biochemical Oxygen Demands
Suspended Solids
Loading /Volume
300,000 gal
120,000 gal
90 gpm
22 hr
90°F
8800 mg/1
6500 mg/1
2650 mg/1
237 Ib COD/ 10 00
40,100 ft3
16,000 ft3
0.13 mgd
0.92 day
32°C
9500 lb/day
7000 lb/day
2800 lb/day
ft3/day
Listed in Table 3 are some of the effluent characteristics of the
anaerobic filters.
Table 3. Anaerobic Filter Effluent Characteristics
Chemical Oxygen Demand 3170 mg/1
Chemical Oxygen Demand (filtered) 47%
Biochemical Oxygen Demands 2930 mg/1
Suspended Solids 1460 mg/1
Volatile Suspended Solids 87%
3400 lb/day
3100 lb/day
Temperature
87°F
Comparing the COD values of the filter influent and effluent
(Tables 2 and 3) an average removal of 64 percent was measured.
Limited investigations of COD removal vs filter height indicated that
although the major portion of waste reduction occurred within the lower
levels of the filter, further reduction was evident in the upper levels.
158
-------
A short-term (30 minute) laboratory sedimentation step, using
filter effluent, revealed that increased efficiency could result by
incorporating this step. An additional 10 percent COD removal was
obtained. The average suspended solids level of the test samples was
1300 mg/1. After the 30 minute settling period the suspended solids
concentration was reduced to 370 mg/1.
CENTENNIAL MILLS STARCH-GLUTEN PLANT
Since much of the starch plant's equipment and process mode is of a
proprietary nature, little can be said relative to the manufacturing
methods. The plant's input is wheat flour and the method of starch
separation is centrifugal. The plant operates three shifts per day
and is shut down for cleaning and maintenance during weekends.
Average values for various waste parameters are listed in Table 4.
These values are consistent with those found in the literature. The
values in the table were derived using 24-hour composite samples except
as noted. The samples were collected in iced containers at 18 minute
intervals. Since the mechanics of plant operation dictate nearly constant
flows to the treatment system, the samples are assumed to be "true"
composites.
159
-------
Table 4. Centennial Mills Starch Plant Effluent
Characteristics
Frequency
of
Flow (gpm)
(mgd)
COD (mg/1)
(///day)
Centrifuged COD (mg/1)
(0/day)
BOD (mg/1)
(///day)
pH*
Temperature* (°F)
(°C)
Total Kjeldahl nitrogen
as N (mg/1)
(#/day)
Ammonia nitrogen as N (mg/1)
(#/day)
Total phosphorus as P (mg/1)
(///day)
Alkalinity* (mg/1)
Volatile acids* t
Suspended solids (mg/1)
(///day)
Volatile suspended solids
(mg/1)
(///day)
Analyses
Daily
2/wk
2/wk
1/wk
Daily
Daily
1 /month
1 /month
1 /month
Daily
Daily
2/wk
2/wk
90
0.13
8800
9500
6200
6600
6500
7000
>7
70
21
370
400
20
21
75
80
680
355
2650
2800
2500
2700
* Grab samples
t All analyses were conducted per EPA (2) except volatile acids, where
the method of DiLallo and Albertson (1) was used.
160
-------
CONCLUSIONS
1. An anaerobic filter can be successfully used to treat high strength
wheat starch-gluten plant waste.
2. No apparent loss of efficiency occurred after a "resting" period
of one month.
3. Potential odor problems can be controlled.
4. Greater than 60 percent organic removal efficiency was obtained
with an average suspended solids concentration of 2600 mg/1 in the
influent.
161
-------
REFERENCES
1. DiLallo, Rosemarie and 0. E. Anderson. Volatile acids by direct
titration. Water Pollution Control Federation Journal, Vol. 33,
No. 4, 356-365. 1961.
2. Environmental Protection Agency. Water Quality Office. Analytical
Quality Control Laboratory. Methods for chemical analysis of
water and wastes. Cincinnati, Ohio. 1971.
3. McCarty, Perry L. Anaerobic treatment of soluble wastes. In: Advances
in Water Quality Improvement, University of Texas Press, Austin,
Texas. 1968.
162
-------
ICE CKEAM WASTEWATER CHARACTERIZATION AND TREATABILITY
by
E. F. DUL*
INTRODUCTION
The purpose of this paper is to present the results of a wastewater
characterization and treatability study performed on an ice cream
processing plant effluent. Particular items of interest are:
an identification of wastewater sources and characteristics
attendant to ice cream processing;
a description of techniques implemented at the plant to reduce
wastes generation;
a description of the techniques used in waste loading projections
and the projections developed for the plant; and,
the results of alternative aerobic biological treatability
studies performed on the wastewater at varying treatment rates
and wastes temperature.
PLANT/PRODUCTION INFORMATION
The plant under investigation is located in the Northeast and operates
eight hours per day, five days per week. Soft ice cream is the chief
production item, with a small quantity of frozen pies also being
produced. Ice cream and frozen pie production operations are shown
in schematic in Figures 1 and 2.
Ice __Cre_am_ processing
The manufacture of ice cream incorporates two basic steps:
preparation of the ice cream base in vanilla and chocolate
flavors; and,
addition of appropriate ingredients (i.e., fruits, nuts,
flavor extracts) to produce a variety of other ice cream
types beyond chocolate and vanilla.
Ice cream base is produced by formulating a blend of cream, water, sugar,
and additives. The resultant mixture is then pasteurized, homogenized,
chilled, and put into interim, refrigerated storage.
Base is withdrawn from storage, as production demands, and is conveyed
*1I. F. Ludwig & Associatcs/Engineering-Scicnce, Inc., Washington, B.C.,
Great Neck, New York
163
-------
Figure 1
SCHEMATIC OF ICE CREAM MANUFACTURE. UNIT OPERATIONS t PROCESSES
DELIVERY
WATER H
LIQUID SUSAR *-
CREAM STORAGE TANKS (4,oOQgal.eaJ r-
CHOCOLATE" FLAVOR
PUMP
MIX STORAGE TANKS
L I
FLAVOR TANKS (SIX)
rh
1
PUMP
AMMONIA
t >
PASTEURIZERS^
CHILLER
PUMP
^.FILLING SPOUT
C w/ FiLLep
PUMP
-------
Fiaure 2
SCHEMATIC Of FROZEN PIE PREPARATION
OTHER INGREDIENTS FLOUR WATER.
.
Ui
DOU&H MACW:NS
FRUIT
HEAT
DOUGH FORMING
Fitted Pies to FROZEN STORAGE
PIE FILLING
FRUIT COOKING
-------
to flavor tanks where the appropriate flavor extract is added. The
blend is then passed through freezers to be converted to a semi-solid
form and then put into three gallon containers for shipment. Fruits,
nuts or a "ribbon" are added to the ice cream, as required, just after
freezing and prior to container filling.
Frozen Pie Preparation
As seen in Figure 2, batch fruit preparation (cooking and cooling),
dough preparation and forming, pie filling and final product freezing
and storage are the unit operations attendant to pie preparation.
WASTEWATER SOURCES
The chief wastewater sources at the plant are as follows:
Process Wastewater;
Domestic Wastewater; and,
Utility Wastewater (i.e., cooling water, boiler blowdown)
The latter two forms of wastewater are segregated from process waste-
water and are disposed of separately in a manner that is satisfactory
to the controlling regulatory agency. Thus, only process wastewater
is Discussed in this paper.
Ice Cream Process Wastevater
Wastewater generation in ice cream processing results from cleanup
operations which can be divided into two general types:
General plant cleanup which occurs at the end of the produc-
tion day. All equipment from the "mix" storage tank dis-
charge pumps to the filling spout is "broken down" and cleaned.
• Sporadic cleanup includes :
Tank Truck Cleanup - Whenever a cream tank truck is emptied,
it must be hosed clean before leaving the plant.
Pasteurizer, Horaogp.nizer, Chiller Flushout - Whenever a run
of mix is completed, this equipment must be flushed out. The
operation is performed by hosing down each pasteurizer vessel
and then pumping the resultant wastewater through the homo-
genizer and chiller and out to waste.
Pasteurizer, Homogenizer, Chiller Rinse-out - This operation
is performed similarly to a flushout except that it is per-
formed only ono. time per day regardless of the volume or
types of mixes prepared. In this operation, water, detergent
and a sanitizcr ore used to prevent a film buildup in the
equipment. No contact with raw ice cream ingredients is made
in this operation.
166
-------
Mix Storage Tank Cleanup - Whenever a mix storage tank is
completely emptied, the tank is hosed down and rinsed with
clean water.
Small Backflush - Whenever a change is to be made in the
type of fruit (or nuts) or ribbon to be added to a given
flavor ice cream, the fruit or ribbon feeder and the piping
from this unit to the filling spout is flushed so that no
intermixing of product types is realized.
•• Complete Backflush - Whenever a significant change in flavor
types is to be made (as for example from vanilla to chocolate),
all the piping and equipment between the flavor tank and the
filling spout must be cleaned. First a small backflush as
described above is performed and then the water hose is fed
into the filling spout to pass water through the piping
back to the flavoT tank discharge valve.
From the foregoing, it should be noted that the number and frequency
of the six sporadic type cleanups in an ice cream plant are a function
of:
• volume of product handled (i.e., this affects the number of
tank truck cleanups and mix storage tank cleanups),
• variations in flavors produced (i.e., this affects the number
and frequency of complete backflushes),
• variations in ingredients added to a given flavor ice cream
(i.e., this affects the number of small backflushes),
the type and volume of base mix (vanilla, chocolate or ice)
produced (i.e., this affects the number of Pasteurizer, Homo-
genizer and Chiller Flushouts).
Pie Plant Process Wastewater
Four types of cleanups are performed in the pie plant; slop sink
cleanup of utensils, cleanup of fruit cooking vats, general floor
cleanup (performed at the end of the day's pie. production and subse-
quent to a dry cleanup of the floor), and pan cleaning performed in
the dishwasher. The most significant of these operations in terms
of wastewater quantity and strength is the general cleanup.
WASTEWATER CHARACTERISTICS
Source^ Wastewater Characteristics
Source wastewater characteristics were determined from analysis of
waste samples collected on a daily basis from each waste source when-
ever the operation occurred. The sampling program spanned 2-1/2 months
so that all flavor type/ingredient effects could be accounted for.
The results of this program in terms of mass emission rates for BOD
and Flow are presented in Table 1. As can be seen in Table 1, the
general plant cleanup yields the highest unit BOD load as well as a
167
-------
TABLE 1
ICE CREAM PROCESSING WASTEWATER CHARACTERISTICS
Average Unit Waster Generation
Unit Operation
General Plant Cleanup
(Major Cleanup)
Tank Truck Wash
Crean Storage Tank
Rinse
Pasteurizer, Homogenizer,
Chiller Flushout
Pasteurizer, Homogenizer
Chiller Rinseout
Mix Storage. Tank Wash
Small Backflush
Complete Backflush
Pie Shop Cleanup
Pan Wash Discharge
Unit BOD Load
(Ibs)
50
1
0
18
0
12
13
25
15
1
Unit Flow
(gals)
1,000
35
0
50
50
50
650
1,300
400
250
Comments
Occurs one time per day at
end of production day.
Occurs on receipt of each
4,000 gal. tanker.
Rinsewater conveyed to
pasteurizer as part of mix.
Occurs at end of base flavor
run. Maximum number of occur-
rences equals 3 per day.
Occurs once per day
May occur up to 5 times per
day.
Occurs up to 6 times per day.
Occurs up to 3 times per day.
Occurs 1 time per day. (Covers
approx. 660 ft of production
area) .
Occurs 1 time per day.
-------
high unit flow. However, more important in terms of their effect on
the overall plant wastewater character, are the unit operations that
can occur more than one time per day. These operations are:
Pasteurizer, Homogenizer, Chiller Flushout;
• Mix Storage Tank Wash;
Small Backflush; and,
Complete Backflush.
The least significant operations in terms of their impact on overall
wastewater character are:
• Tank Truck Wash;
Pasteurizer, Homogenizer, Chiller Rinseout; and,
• Pan Wash Discharge.
Overall Wastewater Character
Table 2 presents the maxima, minima and average characteristics of the
overall process waste stream. The data were acquired over the same
2-1/2 month period utilized to characterize waste source characteristics.
Composite samples were obtained by collecting the total daily waste-
water volume in the existing, aerated equalization tank. The wide
range in data sets shown in Table 2 is caused by the day-to-day varia-
tions in the number of small backflushes, complete backflushes, and
mix storage tank cleanups that are performed.
An alternative method of presenting the total daily BODs load data
Cthat is later (see WASTEWATER CHARACTERISTICS FORECAST, Method II)
shown to be utile in projecting waste loads]] is by use of statistical
analysis. Figure 3 presents the results of such an analysis. As seen
in this Figure, total daily BOD loads, at present, at the plant should
not be expected to exceed 400 Ibs and 340 Ibs more than, respectively,
five and ten percent of the time.
Four recommendations were made for improving the wastestream:
• Convey pasteurizer, homogenizer, chiller flushout wastewater
(see the earlier section entitled CLEANUP OPERATIONS for
description of this operation) to the mix storage tanks rather
than to waste.
• Empty the.mix storage tanks more completely of their contents
before cleanup is initiated.
Closer mix formulation control should be initiated so that a
minimal residual in the flavor tanks remains after production
is completed.
169
-------
TABLE 2
ICE CREAM PROCESSING WASTEWATER CHARACTERISTICS
OVERALL EFFLUENT DATA SUMMARY
Max.
Item Average Maximum Minimum
Total Daily Flow
8pd
BOD (5da.-20°C)
-------
Figure 3
STATISTICAL ANALYSIS OF BOP,. DATA FORTQT/^L PLANT EFFLUENT
S
$
2
(U
O
s
I
e
s
o
&
h
1U
o
or
81
loo
300
300 AQO
B.O.D./PAY
% OFOBSERVATtONS
4- <;iYBN VALUE
versus
GIVEN VALUE (Lbs, 6OD/PAY)
IT pc re entile - 4OO It*. BOP
Ic- 340 Ibv BOD
* - ISO Iks.
OFQ3SERVATIONS * 38
-------
Automatic steam/water mixing valves should be installed on the
hoses which presently do not have them to reduce water wasting
when a hose is dropped and left to run,
PRODUCTION AND UNIT OPERATIONS FREQUENCY VS. WASTEWATER
CHARACTERISTICS FORECAST TECHNIQUE
In order to develop scale-up data for future wastewater flow and strength,
two alternative approaches were employed. The first was to review
wastewater generation in terms of the units of production (i.e., deter-
mine the unit flow and BOD per unit of finished product). The second
approach was to relate wastewater generation to unit operations of
production.
Ice Cream Operations
Present production of ice cream is 32,000 gallons per week or approxi-
mately 2,000 units per day. Ultimate plant production capacity is
expected to be reached in 1975 or 1976 when daily production will be
approximately 6,000 units per day (unit equals one 3 gallon ice cream
container). Note, however, that it is the cleanup operations which
directly affect wastewater volume and strength and these are related
to changes in production items and not directly to the volume of
production. Thus it was decided that investigation of the frequency
of unit production operations was a more precise method of forecasting
wastewater characteristics.
Pie Plant Operations
The only significant wastewater source in pie plant operations was
found to be the floor cleanup performed at the end of the day's produc-
tion. Just as in the case of ice cream preparation, the volume and
strength of waste is independent of the number of pies produced but is
a function of whether or not any pies are made. Although plans exist
to expand the pie plant in the future, no expansion of the processing
area is intened (Note: Expanding the processing floor area would
mean more floor to clean and thus a greater wastewater volume and
strength). The expansion will incorporate new office and freezer
facilities and a more intensive use of the production area.
WASTEWATER CHARACTERISTICS FORECAST
The previous section defined the type of data to be utilized for fore-
casting (i.e., waste generated per unit operation). This section
describes the data analysis methods used in developing the forecast of
wastewater characteristics.
Method I - Unit Process Effects
Using the unit wastes data presented in Table 1 in conjunction with
forecasts regarding the frequency of unit operation occurrence in the
future, estimates of future waste loads were made. These estimates
are shown in Tables 3 and 4. Note that, because of the addition of a
new freezer and attendant piping, the unit BOD and flow factors for
172
-------
TABLE 3
BOD FORECAST
(Based on Unit Operation Waste Data)
Unit
Operation
Unit Waste Load
(Ibs BOD/day)
Future Unit Operation
Frequency*^
Future
Ultimate Waste Load
(Ibs BOD/day)
Tank Truck. Wash
Cream Storage Tank
Pasteurization
Hoinogenization
Chilling Flushout
Mix Stprage Tank Wash
Small Backflush
Complete Backflush
Major Cleanup
Pie Shop Cleanup
1# BOD/receipt
Zero
18ff BOD/flushout
12$ BOD/washout
13* BOD/backflush
25tf BOD/backflush
but 2 parallel
systems exist
Use; 50# BOD/backflush
50# BOD/operation
Use 15#/cleanup
for 660 ft2
1 tanker per day
Zero
Assume 3 flushouts per
day
Assume all 5 tanks washed
per day
Assume 6 per day
Assume 3 per day
1 per day
Future = same as today
Total
1
Zero
54
60
78
150
50
15
408 ibs BOD
per day
*Per analysis with plant manager.
-------
TABLE 4
Unit
Operation
WASTEWATER FLOW FORECAST
(Based on Unit Operation Waste Data)
Unit Flow
(gals.)
Future Unit Operation
Frequency*
Future Ultimate
Wastewater Volume
(gals/day)
Tank Truck Wash
Cream Storage Tank
Pasteurization
Homogenization
Chilling Flushout
Mix Storage Tank Wash
Small Backflush
Complete Backflush
Major Cleanup
Pie Shop Cleanup
35 gals/receipt
Zero
50 gals/flushout
50 gals/washout
650 gals/backflush
1,560 gals/backflush**
1,000 gals/operation
400 gals/cleanup
1 tanker per day
Zero
Assume 3 flushouts per
day
Assume all 5 tanks washed
per day
Assume 6 per day
Assume 3 per day
1 per day
Future «= same as today
(1 operatiqn per day)
*Per analysis with plant manager.
**Increased from 1300 gals by 20% to account for the
extra piping length added by the new freezer.
Total
35
Zero
150
250
3,900
4,700
1,000
400
10,400 gpd
-------
the complete backflush were adjusted upvards. Using this technique,
the projected ultimate BODs and flow were 408 Ibs. per day and 10,400
gallons per day, respectively.
Method II - Analyze Total Plant Effluent
BOD
It was felt that a better account of the effects of "accidents"
in the plant (which would definitely and most importantly affect
wastewater BOD) might be made via a statistical analysis. A
statistical analysis was performed on all the raw sampling and
analysis data. Additionally, the sampling program was modified
so that concentrated wastes generated in the small and complete
backflushes and mix storage tank washouts could be collected
separately over the day in one separate vessel (an abandoned
flavor tank) and sampled separately. Alternately, all other
plant wastewaters (called dilute wastewater) were also sampled
and analyzed separately. The results of the statistical analyses
are shown in Figures 4 and 5. Figure 4 indicates 90 and 95
percentile values of concentrated wastewater BOD per day of 212
Ibs. and 220 Ibs., respectively. Figure 5 indicates 90 and 95
percentile values of dilute wastewater BOD per day of 139 Ibs.
and 147 Ibs. BOD, respectively.
To develop a scaled-up ultimate design BOD load, the following
were noted:
For dilute washwater the conservative 95 percentile value
of BOD of approximately 150 Ibs. per day would be recommended
for use for ultimate design. This is based on the fact that
dilute washwater sources will not significantly change with
time (i.e., pie plant cleanup, general plant cleanup, tank
truck wash).
• For concentrated wastewater, at present, a 95 percentile
BOD of 220 Ibs. per day is noted. To account for an in-
crease in the number of small backflushes per day (from five
performed on 31 March 1971 when the 95 percentile was ex-
ceeded) to an ultimate of six (forecasted by the plant) a
scale-up factor of (6/5 =) 1.2 should be used. To account
for using all the existing and new freezer capacity at the
plant (this affects complete backflushes) rather than only
two small freezers and two barrels of the new large freezer
(Note: This has been the maximum freezer usage to date) a
factor of /6 freezers total \ 1.5 should be used.
Thus, concSnlfiiiS^riErSBli^s^rSSlcted to reach a 95
percentile value of (220 Ibs/day x 1.2 x 1.5 =) 400 Ibs/day.
The projected ultimate 95 percentile of total plant BOD was
thus estimated to be:
175
-------
too-
90
70-
60"
IU
p
I
kJ
IdO
. a. a D / DAY
250
OF
VALUE
versus
6| VEN VALUE .( IW. BOD/DAY)
95
ile » 22O )t», BOD
•iU * 212 Ibs.BOD
i
5*0 pe^CCwH Ic. » 10O Ibfi^ 5OP
OrOBSERVATTONS = 16
-------
Figure 5
ANALYSIS OF BQft. PATA FOR DILUTE WASTE WATERS
10 tO
4c fO <0 70 86
»00 HO
(50 MO
OF OBSERV/ATI0NS
GIVEN VAUL/{f
yevsus
VALUE (
, BOD
. BOD
U- * 95 li». BOD
OF OBSERVATIONS - 17
-------
Dilute Washwater 150 Ibs. per day
Concentrated Uastewater = 400 Ibs. per day
Total 550 Ibs. per day
ALTERNATIVE WASTEWATER TREATMENT AND DISPOSAL TECHNIQUES
Through^-. : the study period as data accumulation and analysis progressed,
alternative wastewater treatment and/or segregation and disposal tech-
niques were reviewed. The chief alternatives that came under review
were:
Alternative I - Treatment of the total daily wastewater on-site
in an extended aeration type aerobic biological treatment plant.
Alternative^II - Treatment of dilute washwaters on-site in an
extended aeration type aerobic biological treatment plant while
concentrated wastewater is treated on-site in an.anaerobic
fermentation treatment plant.
Alternative III - Treatment of dilute washwaters on-site in an
extended aeration type aerobic biological treatment plant while
concentrated wastewater is collected for disposal off-site.
Alternative I was selected as the optimum treatment system for the
following reasons:
Published data (1) indicate that an extended aeration type
aerobic biological treatment plant will produce a high
quality effluent that will meet the demands of the control-
ling regulatory agency.
• Annual costs (amortized capital and annual operation and
maintenance) for Alternative I would be the least and could
be more reliably projected than those for the other alterna-
tives. (Especially as regards Alternative III, off-site
disposal costs are subject to increase with time.)
• Alternative I requires the simplest operation and maintenance
expenditures and labor talent.
• Alternative I has the highest "shock absorbing" capacity of
all the alternative systems studied. The plant will be able
to sustain the effects of in-plant accidents (i.e., accidental
fruit or mix spills) without requiring the plant personnel to
call for outside assistance (i.e., emergency scavenger calls
to pump out an overloaded treatment plant).
LABORATORY TREATABILITY STUDIES
General
In order to define the efficiency of the proposed extended aeration
178
-------
system under various operating conditions, a three component treata-
bility study was developed and implemented.
Phase I of the study was designed to operate at a Food: Microorganism
(F/Ii) ratio averaging at 0.07 (Note: From correlations, BOD = 0.8 COD),
A five liter aerobic reactor was utilized and reactor contents were
maintained at room temperature. In order to simulate field conditions,
the total daily feed volume (i.e., 200 m£) was fed to the reactor in
four equal doses of 50 mJl each over an eight hour period. No feed
was made to the system for the other sixteen hours per day or over
the weekend. The system was operated utilizing actual raw plant
waste (Kote: Concentrated wastes were collected in the field and di-
luted in the laboratory). The resultant hydraulic retention time
was approximately 25 days and nutrient nitrogen was added to the system
to maintain a BOD: N ratio of 20:1.
Phase II of the treatability studies waa designed to simulate long
term shock loading conditions. After operating the Phase I system
for approximately one month, the loading was then increased to a
total of 500 m& per day. All other Phase I conditions were maintained
The average F/il ratio during this period was 0.31 and the hydraulic
retention tiiae was reduced to 10 day,s.
Phase III of the treatability studies was designed to determine the
effects of low temperature on the Phase I system. Phase III was
implemented by reverting from the Phase II to Phase I loading condi-
tions, equilibrating and then putting the reactor into a refrigerator
maintained at 2 -4 C. The results of all the foregoing are presented
in the following sections.
Phase I Results
Phase I operating results are presented in Table 5. Over the period
of 6 May through 9 June, an average mixed liquor volatile suspended
solids (MLVSS) of 2,290 mg/£ was maintained in the reactor. With an
influent COD averaging at approximately 5,050 mg/£ (i.e., BOD aver-
aging at 4,050 mg/A) over this same period, the food-to-microorganism
(F/M) ratio in the system was:
JF = //BOD = 4050 mg/& x 0.2& =
M #MLVSS 2290 mg/£ x 5 A
COD removals throughout this period ranged from a lovr of 93.0 percent
to a high of 97.7 percent with an average of 95.8 percent. Good
settling of the resultant sludge was reported once the system reached
equilibrium (starting 21 1-Iay) yielding an average Sludge Volume Index
(SVI) of approximately 160.
Another important result of the study can be seen by inspecting COD
removal efficiency data over weekend periods. The data in Table 5
indicate that insignificant changes in the system efficiency resulted
over the weekend periods in spite of the fact that no waste was fed
to the system over the weekend in an attempt to simulate actual field
conditions.
-------
TABLE 5
ICE CREAI1 PROCESSING WASTEWATER
EXTENDED AERATION TREATABILITY STUDY RESULTS (F/M - 0.07}
68° F)
DATE
5-6
5-7
5-8
5-9
5-10
5-11
5-12
5-13
5-14
5-15
5-16
5-17
5-18
5-19
5-20
5-21
5-22
5-23
5-24
5-25
5-26
5-27
5-28
5-29
5-30
5-31
6-1
6-2
6-3
6-4
6-5
6-6
6-7
6-8
6-9
AVG.
pH
6.1
6.0
-
-
5.35
5.6
5.25
5.2
5.2
-
-
5.1
5.0
4.9
4.8
4.7
-
-
4.6
4.6
4.3
4.6
4.5
-
-
4.5
4.9
4.6
4.55
4.75
-
-
4.2
4.3
4.3
SETTLE-
ABILITY
mi/a
980
980
-
-
980
980
985
980
980
-
-
970
970
920
920
380
-
-
520
760
400
350
320
-
-
300
300
290
250
230
-
-
240
230
220
342
TSS
mg/Jl
4880
4380
-
-
4267
4300
4400
4200
3700
-
-
3200
3150
3050
2860
2750
-
- '
2580
2430
2530
2420
2150
-
-
1900
2070
2150
1980
1718
-
-
2010
1970
1750
2762
VSS
mg/i
4100
3700
-
-
3633
3640
3600
3550
3200
-
-
2600
2900
2550
2400
2220
-
-
2100
2020
2030
I860
1780
-
-
1700
1650
1820
1720
1180
-
-
1490
1625
1420
2290
INFLUE13T
COD
ras/fc
. -
-
-
-
5390
5200
4960
4930
4900
-
5096
5350
5400
4940
5300
5280
-
-
5352
5450
4840
5340
5300
-
-
5150
5060
4940
5080
5340
-
-
3240
4500
4980
5054
EFFLUEUT
COD
mg/S,
-
-
-
-
167
144
310
188
330
-
333
310
312
384
368
220
-
•-.
192
190
120
176
160
-
-
120
140
192
176
140
-
_
140
150
150
212
Z
COD
REMOVAL
-
-
-
-
96.9
97.2
93.7
96.2
93.2
-
93.4
94.2
94.2
92.2
93.0
95.8
-
-.
96.4
96.5
97.5
96.7
97.0
-
-
97.7
97.2
96.1
96.5
97.4
—
_
95.7
96.6
97.0
95.8
180
-------
Phase jl Results
The results of the Phase II (i.e., shock loading condition) operations
are presented in Table 6. Except for the first day of operation
wherein the COD removal efficiency dropped to 88.0 percent from 97.0
percent on the previous day, no adverse effects on system operation
were noted. For the two-week period following the first increase in
loading, the system COD removal efficiency ranged from a low of 91.4
percent to a high of 95.6 percent, with an average of 94.0 percent.
System operating parameters were as follows:
Average MLVSS 1038 mg/Jl
Average Influent COD = 4072 mg/A
Average Influent BOD = 3250 mg/Jl
Average ^ = 3250 mg/Jl x 0.51 _
Average - 0.31
The sludge settleability was found to be very good with an average SVI
of 63. Again, no adverse effects were noted as a result of "starving"
the system over the weekend.
Phase III Results
The results of the Phase III (i.e., chilled conditions) treatability
program are presented in Table 7. Inspection of the data in Table 7
indicates that the COD removal efficiency ranged from a low of 88.9
percent to a high of 95.6 percent and averaged at 93.0 percent. Sludge
settleability was again found to be very good with a resultant SVI of
72. Weekend "starving" of the system produced no adverse effects. The
system was maintained at an average F/ll ratio of approximately 0.14.
The chilling study results were compared with the work of Clark, et
alv2). Clark concluded that, "...several investigations have col-
lected data for aerated lagoon operation performance within the
temperature range of 0 C to 10 C...the curves Cin Figure 6j demon-
strate that there is a high probability for obtaining BOD removal
efficiencies greater than 80 percent at detentions less than 15 days
with lagoons operating at temperatures less than 5 C." The results
of the Phase III program compare favorably with the data/conclusions
reported by Clark.
CONCLUSIONS
The most significant conclusions that can be drawn from the foregoing
are as follows :
• Ice cream wastcwater characteristics are chiefly a function of
the type and number of cleanup operations performed.
• Opportunities do exist for wastewater volume and strength reduc-
tion in an ice cream processing plant. However, the potential
181
-------
TABLE 6
ICE CREAM PROCESSING WASTEWATER
HIGH RATE TREATABILITY STUDY RESULTS (F/M = 0.31; 68 F)
DATE
6-10
6-11
6-12
6-13
6-! 4
6-15
6-!6.
6-17
6-18
6-19
6-20
6-21
6-22
6-23
6-24
AVG.
SETTLE-
pH ABILITY
4.6 155
5.1 150
-
-
5.2 80
70
6.0 70
80
6.1 70
_
-
64
5.0 70
5.0 70
5.75 65
86
TSS
1925
1680
-
-
1220
1550
1400
1200
1130
-
-
1430
1000
MOO
1350
1362
VSS
1075
1500
-
-
1020
1075
1200
1025
900
-
-
M80
600
900
950
1038
INFLUENT
COD
mg/Z
5920
4960
-
-
4720
4080
4000
3360
3240
-
-
3600
3160
3320
4120
4072
EFFLUENT
COD
mg/A
712
220
-
-
214
196
180
160
236
-
-
192
148
170
352
244
COD
REMOVAL
88.0
95.6
-
-
95.5
95.2
95.5
95.2
92.7
-
-
94.7
95.3
94.9
91.4
94.0
182
-------
TABLE 7
ICE CREAII PROCESSING WASTEWATER
"WIKTER" OPERATING RESULTS FOR EXTENDED AERATION (F/l-I =0.14; 2°C - 4°C)
DATE
7-7
7-8
7-9
7-10
7-11
7-12
7-13
7-14
7-15
7-16
7-17
7-18
7-19
7-20
7-21
7-22
7-23
7-24
7-25
7-26
7-27
AVG.
TeiP(°C) pH
4 7.5
4
3
.
-
2
3
2
4
4
-
-
2 6.1
4 6.1
3 5.8
4 5.6
4 5.4
-
-
2
3 5.6
-
SETTLE-
ABILITY
50
60
-
-
-
60 -
-
-
90
80
-
-
85
70
80
70
90
-
-
-
100
76
TSS
_
1010
1215
-
-
1020
1030
1115
1230
1280
-
-
1285
900
910
766
900
-
_
930
1 133
1051
VSS
mg/A
—
713
1000
-
-
-
715
800
1030
1040
-
-
865
780
806
613
860
-
-
900
1013
856
INFLUENT
COD
mg/A
2740
3100
2760
-
-
2880
3340
3260
3230
2680
-
-
2960
5580
5680
5120
4768
-
-
5472
5810
3958
EFFLUENT
COD
mg/A
212
320
308
-
-
216
210
204
180
180
-
-
150
428
248
332
384
-
-
338
296
277
% COD
REMOVAL
92.3
89.7
88.9
-
-
92.5
93.7
93.7
94.4
93.3
-
-
94.9
92.3
95.6
93.5
91.9
-
-
93.8
94.9
93.0
183
-------
Mgure b
AERATED
AGOONS
PE R FOR M A MCE £ FFICJ EM C i ES
00
100^
90 J-
80..
(O
>
C
CJ
o:
a 70..
o
*
CO
60..
50
•4-
X Gellman ( 3} Kraft Wastes
2°C
• Gellmen ( 3} Kraft Wastes
10°C
O Sawyer (12) Textile Wastes
13°C
4. Townsend (14) Donestic and
Seasonal Winery Wastes
O McKinney ( 7) Domestic Wastes
0-5:C
. Reid (10) Domestic Wastes
o-rc
5 TO 15
Detention Time (Days)
20
-------
for accidental raw/finished product spills should not be under-
estimated.
Overall wastewater characteristics in an ice cream plant are
highly variable because of day-to-day changeovers in types
and quantities of ice cream produced.
COD removal efficiencies of 94-96 percent can be achieved in
aerobic biological treatment units handling ice cream waste-
waters at F/M ratios in the range of 0.07 to 0.31.
No significant change in system operating efficiency resulted
when a pilot extended aeration plant (operating an ice cream
wastewater) was operated at room (20 C) and subsequently under
cold (2 -4 C) temperatures.
185
-------
LIST OF REFERENCES
1. "EFFICIENCY OF VARIOUS METHODS OF TREATMENT, MILK PLANT WASTES,
HEW YORK", Research Report No. 2, New York State Water Pollution
Control Board, N.Y.S. Dept. of Health, October 1959.
2. CLARK, S.E., COUTTS, H. J., JACKSON R., Alaska Sewage Lagoons
presented at the "2nd International Symposium For Waste Treatment
Lagoons", sponsored by Missouri Basin Engineering Health Council
& Federal Water Quality Administration, June 23-25, 1970, Kansas
City, Missouri.
186
-------
THE USE OF CHEMICAL TREATMENT AND AIR FLOTATION FOR
THE CLARIFICATION OF FISH PROCESSING PLANT WASTE WATER
F. G. Claggett
INTRODUCTION
The water used by fish processing plants may be a source of pollution if
released into confined waters because of the large volumes and the high
levels of organics involved. The effects on the benthic environment of
discharges from plants located on seacoasts and river estuaries has been
shown to be relatively harmless (9.10).
An analysis of the effluent from almost any fish processing operation
shows that the water contains discrete particles of fish ranging from
screen to colloidal in size, free fish oil, soluble proteins, sugar
phosphates, mineral salts, and various emulsions of these. The extent
of each component will vary depending mostly on the species being pro-
cessed, but also on the condition of the fish, type of processing
operation, the amount of water used, and the type of treatment prior to
release. Many reports are available on the characterization of the
water from various processed species, and several projects are currently
underway (1,11,12), A typical analysis of water from a salmon can-
ning operation is shown in Table I.
At the request of the Fisheries Association of British Columbia, in
196? the Vancouver Laboratory of the Fisheries Research Board of Canada
undertook a survey of the existing pollution problems in the B.C.
fishing industry in order to recommend to the companies a course of
action to meet the upcoming regulations (2) .
Table I. An Analysis of Wastewater from a Salmon Cannery
Insoluble Solids 1200 mg/1.
Soluble (non-salt) Solids 1500 mg/1.
Protein (as N x 6.25) 1800 mg/1.
Biochemical Oxygen Demand 2500 mg/1.
Chemical Oxygen Demand 4000 mg/1.
Turbidity 2500 JCU
pH 6.3
Color Plnk
^Fisheries Research Board of Canada, Vancouver Laboratory, Vancouver, B.C.
187
-------
SURVEY RESULTS
Biological treatment at the plant site would in most cases be impossible
due to the intermittent nature of operation of this industry. Extremely
large lagoons would be required to handle the slug loads encountered
during start-up of operations, and would have to be aerated, since
anaerobic operation would lead to the production of obnoxious odors due
to the high level of sulphur-containing compounds present. Moreover,
for a salmon cannery to reduce the BOD level of its effluent from 2500
to 50 would require a system capable of operating in excess of 98 per-
cent efficiency.
In many cases it is possible to use municipal sewerage systems, since
the organics present are readily degradable. The high flows and
organic loading might easily overload or upset small systems. A sur-
charge can be expected to be applied by the municipality, due to the
high levels of suspended solids, free oil and BOD. One report (ll)1
gives a formula used by many municipalities which predicts that a
200,000 case per year cannery can expect to pay about $75.00 per day
surcharge, or roughtly $0.02 per case. This will probably be the
cheapest treatment available.
Since the wastewater contains mostly protein and fish oil, by-product
recovery was suggested as a logical first step in the operation. The
survey showed that the screening used in the industry was most rudi-
mentary, seldom exceeding the use of 1/4 inch mesh trommel screens.
Attempts to use finer screens either of the trommel or vibrating types
had failed in the past due to the "blinding" action of the raw protein
or fish oil. The first objective then, was to determine if types of
screens were commercially available that could achieve better solids
reduction.
Sedimentation could only be expected to be partially successful since
the solids and oil have a specific gravity close to one. The use of
chemical treatment for precipitation and flocculation, however, and air
flotation for solids and oil removal suggested itself because of the
nature of the pollutants. Since most fish processing plants have or
are near to equipment for converting waste solids to fish meal (a
poultry feed ingredient) and fish oil, the skimmings could be processed
for recovery there.
The second objective suggested by the survey report was to investigate
this treatment on a bench and pilot-plant scale, and to follow this up
with a demonstration plant if warranted.
FLOTATION THEORY
The theory of flotation may be examined in depth by reference to the
works of Gaudin (8) and Vrablik (13). Briefly, all types of flotation
cells are similar in principle, although they may differ physically.
They operate by the release of air as tiny bubbles from an air water
solution through the use of a pressure drop, and the use of this air
to obtain a rapid flotation of the solids. The main differences in
the type of cells are in the amount of water pressurized (i.e., total
versus partial flow pressurization), in the manner in which the air is
188
-------
injected into solution, and in the configuration of the flotation cell.
A typical arrangement of equipment for total flow pressurization is
shown in Figure 1. Water from the collection tank is pressurized by a
centrifugal pump and control valve to roughly 3 atmospheres. Air is
injected into the pump suction (as shown) or into the retention tank
through a sparger, at roughly two percent of the volumetric flow rate.
The retention tank allows sufficient time for most of the air to enter
solution. As the water pressure drops in passing through the control
valve, the air comes out of solution as pin-point bubbles and collects
on any interface present. As the air-water-solids mixture enters the
flotation cell, the air will cause the solids and oil to rise rapidly
to the surface where they may be removed by skimming. Clarified water
is removed from the bottom of the cell. A recycle line is ordinarily
connected between the flotation cell and the collection tank to auto-
matically adjust for liquid flow variations and to allow second-pass
treatment.
CHEMICAL TREATMENT
Certain chemicals have been used extensively with flotation cells to
assist in the separating action by precipitation and flocculation.
Many combinations were tested by us, including activated alumina, silica
gel, ferric chloride, and numerous polyelectrolytes.
Considerable time was spent in investigation of a by-product of the
pulp and paper industry. This derivative of lignosulphonic acid has
the ability to quantitatively react with proteins under acid conditions,
allowing substantially complete removal. Unfortunately, several inherent
properties prevented its use with the flotation cell. Primarily, the
compound must be added on a direct ratio with the quantity of protein
present, a value which is not readily determined. In addition, the
resulting floe is very fragile, and hence not easily removed.
Early tests with aluminum sulphate (alum) showed some promise, but the
floe was very small, and slow forming. A literature search revealed
that a certain level of alkalinity was required in the water before
this chemical could act efficiently''. Since the water used by plants
in the Vancouver area is quite soft, jar tests indicated that about
75 mg/1. of sodium hydroxide was required for proper floccing action.
This raised the pH of the water to 9.2. Sufficient alum (or mixture
of alum and acid) is then added to lower the pH to between 5.0 and
5.5. A curdy floe is formed which floats readily in the presence of
air bubbles. The source of alkalinity appeared to be immaterial, as
the system worked with sodium hydroxide, ammonia, lime or soda ash.
Eckenfelder (?) explains the action as follows: the alkalinity converts
the charge on the surface of colloids, proteins, flesh particles and
oil droplets to negative. As alum is added, the cations are attracted
by'the opposing charges, thus coating the material. Microflocs are
thus formed, which retain a positive charge in the acid range because
of the absorption of hydrogen ions. Flocculation agglomerates the
particles with a hydrous oxide floe. In this phase surface adsorption
is also active. Colloids not readily adsorbed are removed by enmeshment
in the floe.
189
-------
WASTE WATER FLOW
FIGURE 1
AIR FLOTATION
-------
Since the solubility of proteins is decreased as one lowers the pH
toward the isoelectric range, (4-0 to 4.7) a lower pH will favour the
removal of soluble protein. The optimum pH for floe formation, however,
is about 5.2. Anionic polyelectrolytes have been found useful in ex-
tending the range over which the floe may be formed, and in increasing
the rate of floe formation.
PILOT PLANT STUDIES
The pilot plant programme was funded for two years by a grant made to
the Fisheries Association of B.C. by the Industrial Development Service,
Department of the Environment. The design of the programme for the
first year was made primarily to familiarize ourselves with air flot-
ation and to investigate the problems of operations of this type. A
comprehensive description of this test is given in the Vancouver Labor-
atory Circular 38 (3)- The equipment layout was similar to that in
Figure 1. The unit chosen was a 50 GPM Pacific Flotator, supplied by a
division of the Carborundum Corporation.
The equipment was installed at the Paramount Cannery of Nelson Brothers
Fisheries, Steveston, B.C. Piping was arranged to take approximately
one-tenth of the total waste flow at a point following screening by
a 1/4 inch trommel.
A number of problems were encountered in the first year which had to be
overcome for the next year's test. The slow floe formation was the
chief one, which, as explained earlier, was overcome by the addition of
alkalinity. The coarse screening supplied allowed large solids
particles to settle in the collection tank and flotation cell, and to
plug the aspirator for air injection. This pointed up the need for
better screening. Attempting to control the chemical addition by pH
measurement looked promising, despite the tendency of the reference
electrode to plug with fish oil or fine solids.
By reviewing the results of the first year's work, we were able to make
considerable changes in the layout of equipment for the second year.
The flotation pilot plant obtained for the second season was a 50 GPM
"Favair" unit supplied by Permutit of Canada. This allowed us to
contrast the operation of a rectangular cell with a circular one, and
to view the operation where air is injected by compressor rather than
by aspirator. In our opinion, there was little to choose between the
two units. The plant layout for the second year is shown in Figure
2, and a full description of the test is given in FRB Laboratory
Circular 42. (4).
Two types of screens were tested for fine solids removal. The North
Sewerage Screen (supplied by Green Bay Foundries, Green Bay, Wisconsin)
is a submerged rotary screen panelled in this case with a 34 mesh
stainless steel screen. See Figure 3. The unit tested was a 4-foot
model, rated at 100 GPM.
The other screen tested was of the tangential type, a 1-foot cross-
section model DSM screen (supplied by Dorr-Oliver Company). Screen
meshes of 20 and 40 were tested. The operating principles are shown
in Figure 4.
191
-------
VO
N>
INFLUENT
TROMMEL
t
TANGENTIAL
SCREEN
1 ROTARY
jSCREEN
COMPRESSED.
AIR
«•
SLUDGE
C j « Cj
r-****
L_J
EFFLUENT
, — _^ — — . . — i — —
FLOTATION CELL
"^"•~
V
CHEMICAL
ADDITION
\
i i
RETENTION TANK
CHEMICAL
ADDITION
SURGE TANK
PIGURE 2 PILOT PLANT LAYOUT
-------
CANNERY WASTE WATER
WATER SPRAY
ROTARY SCREEN
FIGURE 3 NORTH SEWAGE SCREEN
-------
WASTE WATER
w^
OVERSIZE
TANGENTIAL
SCREEN
FIGURE
DSM TANGENTIAL SCREEN
194
-------
Both the tangential and rotary screens worked well on salmon-canning
wastewater. Operating results are shown in Table II. Some gradual loss
in capacity occurred with time with both screens, but this was readily
corrected by the use of water sprays.
Table II. Solids Removal from Salmon Canning,Wastewater by Screening
DSM Screen
40 Mesh
Feed
Undersize
Oversize
Total Solids
(G/L)
4.5
2.5
164.0
North Screen
3k Mesh
Feed
Undersize
Oversize
Total Solids
(G/L)
4.2
2.4
105.1
Table III. Solids Removal from Herring Pump Water by Screening
Stream
Feed
Undersize
Oversize
Tangential Screen
Total Solids (G/L)
6.91
4.58
143.06
North Screen
Total Solids (G/L)
7.36
3.56
111.04
Several herring vessels were unloaded during the season and the pump-out
water passed through the screens and flotation cell. The screens worked
without too much difficulty although the DSM screen exhibited problems
with the scales. The suppliers suggested that a rapping device might
correct this situation. The rotary screen operated with reduced
capacity, but showed no tendency for the capacity to drop beyond about
75 GPM because of the washing of the submerged surface.
The caustic-alum treatment provided clarification with little floe
carry-over, even at rates exceeding the nominal capacity of the unit.
The dosage rates averaged 375 mg/1 of alum and 75 mg/1 of sodium
hydroxide. A suamary of the results can be seen in Table IV.
The overflow sludge averaged 4.5 percent of the total flow, with an
analysis averaging 4.0 mg/1 insoluble solids and 0.4 mg/1 soluble
solids. The data obtained on the solids recovered from the sludge by
heating, centrifuging and drying a» given in Table V. A sample of this
recovered solids was submitted to the University of British Columbia
195
-------
Table IV. Flotation with Caustic-Alum
Stream
Influent
Effluent
Insoluble
Solids
(mg/1)
^X _3_
640 250
180 70
Soluble
Solids
(mg/1)
X^ 3^
2045 675
1305 505
Protein
(mg/1)
JC 8
1440 395
435 240
BOD
(mg/1)
X 3
1775 915
475 315
% Removal 70 12 38 17 65 18 73 23
1. x is the mean, s is the standard deviation.
2. The data are the result of 8 test runs.
Poultry Science Department for evaluation as a supplement in chick
starting rations. The meal was included at 2.5* 5.0 and 15.8 percent
of the ration, and substituted isonitrogenously for herring meal plus
glucose in the control diet. Because of the possible adverse effect of
alum, diets containing this ingredient at levels of 0.5 and 1.0 percent
were included in the experiment.
The resulting data show that, in a diet in which herring meal is the
source of supplementary protein, up to 5 percent of the sample could be
included without adverse effects. When the sample was tested as a total
replacement, there was a marked reduction in both growth rate and food
utilization. The inclusion of alum in the diet at up to the 1 percent
level had no significant effect.
Limited tests of the flotation cell herring pump water indicated
that results similar to those obtained from treatment of salmon canning
wastewater can be expected.
Table V. Analysis of Solids Recovered from the Sludge
Protein (N x 6.25) 50.5#
Ash 10.9£
Moisture 7.7£
Fat 16.558
Aluminium 0.5#
Note: The data totals only 85.6£, the balance being
water of hydration held by the alum.
196
-------
DEMONSTRATION UNIT
At the conclusion of our pilot plant studies a further grant was made
to the Fisheries Association of B.C. to install a demonstration waste-
water treatment unit. This was installed in the spring of 1971 at the
imperial plant of B.C. Packers Ltd., Steveston, B.C. We designed it
to handle the total water flow from their cannery, a total of some 650
GPM. The design details are given in FRB Technical Report 197 (5).
Basically, the unit consists of coarse screening, then fine screening
through 6-foot DSM tangential screens of .7 nun. The oversize solids
are settled in a small tank prior to mixing with the fish plant wastes.
The screened liquid is pumped to a 60,000 gallon buffer tank, from
where it is withdrawn by gravity flow to a model 1250 Pacific Flotator
(supplied by Carborundum Corporation). The wet well for the pumps also
acts as a caustic treatment tank for pH adjustment to 9.2. The use of
the solid reference electrodes (Lazaran) in our pH indicating system
has effectively eliminated problems encountered previously. After
pressurization and air addition, alum is added to the water under pH
indication to adjust the pH to 5.2. Provisions have been made to add a
polyelectrolyte for test purposes. Sludge is skimmed from the tank top
and pumped to the reduction plant for protein and oil recovery. The
clarified liquid requires pH adjustment to 6.0 prior to release.
A summary of the results obtained during the first season's operation
is given in the FRB Technical Report 286 (6). These are given briefly
in Tables VI and VII. Since the sludge recovery procedure is being
re-evaluated at present, analysis of the operating costs can only
include costs to the point of sludge separation. This is estimated at
$0.26 per thousand gallons, including the cost of a full-time operator.
The data can be extended to show that the value of the recovered solids
is about $1.12 per thousand gallons. On this basis, the value of the
recovered solids should offset the sum of the unit operating and sludge
recovery costs.
Table VI. Operating Data on DSM Screens
Influent insoluble solids - 1650 ± 290 mg/1
Effluent insoluble solids = 960 ± 185 mg/1
Oversize solids content - 13£
Solid recovery « 200 Ib/hr
197
-------
Table VII. Operating Data on Flotation Cell
Stream
Influent
Effluent
Insoluble
Solids
(ms/1)
959 t 360
61 t 28
Soluble
Solids
(mg/1)
1590 t 245
1075 t 155
Protein
(ms/1)
1545 t 440
567 t 135
COD
(msA)
5635 t 2498
815 t 125
Oil
(mg/1)
360
20
Turbid-
ity
JCU
2500
200
Removal (%} 92 t 5 28 t 16 6l t 17 84 t 6
Sludge volume flow is 2 to 3% of cell flow rate,
Sludge average dry solids is 7.2 - 2.6%.
Chemical consumption
Sodium hydroxide = 85 mg/1
Alum = 235 mgA
THE FUTURE
We are planning to operate the unit for another year to obtain firm
operating costs, at which time a full report will be made available to
all interested parties. We are also planning to extend our investiga-
tions to the biological treatment of the clarified water, and the
possible use of reverse osmosis. We will endeavour, wherever possible,
to extend cooperation to those interested in using this system for any
type of food processing wastewater treatment.
198
-------
LITERATURE CITED
1. BRODERSEN, K. Personal communication. Paper in preparation.
University of Ottawa: (1971).
2. CLAGGETT, F.G. Clarification of waste water other than stick-
water from British Columbia fishing plants. Fish. Res. Bd.
Canada, Tech. Rpt 14, 7 p. (1967).
3. CLAGGETT, F.G., and Wong, J. Salmon canning waste water
clarification, Part I. Fish. Res. Bd. Canada, Vancouver
Laboratory* Circular No. 38, 9 p. (1968).
4. CLAGGETT, F.G., and Wong, J. Salmon canning waste water
clarification, Part II. Fish. Res. Bd. Canada, Vancouver
Laboratory, Circular No. 42, 25 p. (1970).
5. CLAGGETT, F.G. A proposed demonstration plant for treating fish
processing plant wastewater. Fish. Res. Bd. Canada, Tech. Rpt
197, 10 p. (1970).
6. CLAGGETT, F.G. Demonstration wastewater treatment unit. Interim
report 1971 salmon season. Fish. Res. Bd. Canada, Tech. Rpt 286,
6 p. (1972).
7. ECKENFELDER, W.W., JR. Industrial water pollution control.
McGraw-Hill Book Company, New York: pp. 90-92. (1966).
8. GAUDIN, A.M. Flotation. McGraw-Hill Book Company, New York.
(1957).
9. LAWLER, P. Personal communication. Stanley and Associates,
Consulting Engineers, Vancouver, B.C. (1971)•
10. NAKATANI, R., BEYER, D.L. and HAUDE, C.P. The effects of salmon
cannery waste on water quality and marine organisms at Petersburg,
Alaska. A report submitted to the National Canners Association.
Fish. Res. Inst., U. of Wash., Seattle, Washington, 46 p. (1971).
11. SODERQUIST, M.R., WILLIAMSON, K.J., BLANTON, G.I., PHILLIPS, D.C.,
LAW, O.K., and CRAWFORD, D.L. Current practice in seafoods
processing waste treatment. Environmental Protection Agency,
Water Quality Office, Washington, D.C., Project 12060 ECF.
119 p. (1970).
12. VILLAMERE, J. Personal communication. Environmental Protection
Service, Vancouver, B.C. (1971).
13. VRABLIK, E.R. Fundamental principles of dissolved-air flotation
of industrial wastes. l2th Industrial wastes Conference Proceed-
ings, Purdue University, pp. 745-778. (1957).
199
-------
TERTIARY TREATMENT OF COMBINED
DOMESTIC AND INDUSTRIAL WASTES
by
Harold W. Thompson* and Kenneth A. Dostal*
INTRODUCTION
This paper is a status report on the Environmental Protection Agency's (EPA)
Research and Demonstration Grant No. 11060 DLF. This grant was awarded
to the City of Tualatin, Oregon in 1968; and provided funds for the
construction and evaluation of a full-scale tertiary system treating
combined domestic and industrial liquid wastes.
The data presented herein are based on an initial evaluation of the
raw data collected by the grantee between August 1970 and November 1971.
A final report covering all aspects of the grant will be prepared by
the grantee's technical consultant. The final report should be available
for public dissemination during the fall of 1972.
GRANT'S OBJECTIVES
The general objective of the grant was to develop operating and design
criteria for a chemical-physical tertiary waste treatment system.
Operation of this system was to demonstrate phosphorus removal from the
effluent of an extended aeration waste treatment system.
Specific objectives of the grant were to:
1. Demonstrate the biochemical oxygen demand (BOD), suspended solids (SS),
and phosphorus (P) removal capabilities at a full scale automated
chemical-physical tertiary treatment system treating a combined domestic
and industrial waste.
2. Demonstrate the applicability of this tertiary treatment system as an
effluent upgrading process for existing activated sludge plants and
modifications thereof.
3. Demonstrate the use of tube-type clarifiers for use with extended aeration
systems as a substitute for conventional clarifiers.
4. Determine the operational and disposal problems associated with the
chemical and biological sludges.
*Sanitary Engineer and Chief, Food Waste Research Section, respectively,
National Waste Treatment Research Program, National Environmental Research
Center, U.S. Environmental Protection Agency, 200 S.W. 35th Street,
Corvallis, Oregon 97330.
201
-------
5. Develop design and operating criteria on this treatment system.
6. Determine the economics of the chemical-physical tertiary system.
PLANT DESIGN
Prior to 1968, Tualatin did not have a municipal sewage collection or treatment
facility. It was established by the City of Tualatin that the treatment
facility be designed to treat the liquid wastes from: the City of Tualatin,
two major planned residental subdivisions, a future trailer park, a pet
food processing plant, and several existing light industrial establishments.
The plant constructed to treat the waste from the above sources consists of
an extended aeration biological unit followed by a package chemical-physical
tertiary system. Figure 1 is a schematic diagram of Tualatin's waste treatment
system (WTS).
Alum was added to the extended aeration effluent (see Figure 1) in the
form of ^2(804)3-14 HoO to enhance removal of SS and P. An anionic
polyelectrolyte (Cyanamide 836A) was evaluated as both a coagulant and
filter aid.
The unit operations and processes contained within Tualatin's WTS along with
specific design features are listed below. Design loadings and/or volumes
of the unit operations are tabulated in Table 1.
1. Comminution
2. Extended aeration with:
a. Floating mechanical aerators
b. Aeration basin lined with polyvinyl chloride sheet
c. Aeration basin designed to be utilized as a flow equalization basin
d. Discharge from basin controlled by a pneumatically actuated
discharge pump
3. Tube-type clarifier located within the aeration basin
4. Constant head flow splitter box designed to allow any selected constant
flow rate to be fed to the tertiary system
5. Flocculator
6. Tube-type solids separator
7. Mixed media gravity filter
8. Combination backwash storage and chlorine contact tank
202
-------
INFLUENT WASTE
STREAM
A
EXTENDED
AERATION
TUBE
CLARIFIER
f*
CHEMICAL FEED (ALUM)-
NOTE: TUBE CLARIFIER PHYSICALLY
LOCATED WITHIN AERATION
BASIN
FINAL
EFFLUENT <*-
COMBINED
CHLORINATION
AND BACKWASH
TANK
PUMP
-POLYMER FEED
(ANIONIC)
FLOCCULATORn
TUBE
SETTLER
MIXED
MEDIA
FILTER
—POLYMER FEED
(ANIONIC)
FIGURE 1- FLOW DIAGRAM, TUALATIN'S M&I WASTE TREATMENT PLANT
203
-------
Table 1. Design Data on Tualatin's M&I Waste Treatment Plant
Average Design Flow
BOD Loading
Aeration Basin
Floating Aerators (2)
Basin Capacity (Max-Min)
Tube Clarifier
Overflow Rate
Angle of Tubes (from horizontal)
Flocculator
Volume
Detention Time 0235 gpm
Tube Type Solid Separator
Overflow Rate @235 gpm
Angle of tubes (from horizontal)
280,000 gpd
700 Ibs/day
15 Hp (ea.)
280,000-210,000 gals.
2 2
2 gpm/ft or 2880 gpd/ft
60°
3500 gals.
15 min.
1.7 gpm/ft'
7.5'
Chemical Sludge Decant Tank Cap.
Backwash Storage Tank Cap.
Alum Storage Tank Cap.
Polyelectrolyte Mixing Tank
Polyelectrolyte Feed Tank
Chemical Sludge Dewatering Ponds (2)
Excess Activated Sludge Dewatering Ponds (2)
Mixed-Media Filter (Gravity Filter)
Depth of Filter
Composition of Filter
Hydraulic Loading @235 gpm
10,000 gals.
10,000 gals.
4,000 gals.
750 gals.
750 gals.
300,000 gals, (ea.)
56,000 gals, (ea.)
30 In.
17" Coal, 9" Silica, & *" Garnet
4.8 gpm/ft2
204
-------
9. Chemical sludge decant tank with:
a. Supernatant from decant tank pumped either to the aeration basin
or to chemical sludge storage lagoons
b. Decanted sludge pumped to sludge storage lagoons
10. Chemical sludge and excess activated sludge dewatering ponds with
overflow from the ponds being returned to the aeration basin
11. Chemical storage tank
12. Polymer mixing and storage tanks
PLANT OPERATING PROBLEMS
Upon initiating Tualatin's waste treatment system the normal shakedown
of operating, equipment and design problems began. The major problems,
along with their solutions, that occurred during the evaluation phase
of the grant are discussed in the following paragraphs.
The first major problem occurred when gas collected under the PVC liner
and caused the liner to float in the aeration basin. The liner was reinstalled
according to design; however, after a few days of operation the liner again
appeared at the surface of the lagoon. Prior to installing the liner
for the third time a gas collection system, vented to the atmosphere, was
installed under the PVC and to this date no further liner problems have
been experienced.
After a month of continuous operation the SS removal efficiency of the
tube-type clarifier decreased rapidly. Effluent SS concentrations of 100-
300 mg/1 were not uncommon. SS concentration of this magnitude had an adverse
effect on the length of filter runs. Upon inspection of the tube clarifier
it was apparent that the solids within the unit were being buoyed to the
surface by gas bubbles. At one point the entire tube pack floated to the
surface. Based on these observations it was concluded that the solids were
being concentrated within the tubes for extended periods of time. This
condition accompanied by a highly nitrified mixed liquor resulted in
denitrification which resulted in solids being transported to the surface
by bubbles of nitrogen gas. The equipment supplier developed an intermittent
air sparging system for breaking up the solids within the tubes and thus
allowing the solids to slough from the tubes. This sparging system has
markedly improved the solids removal efficiency of this clarifier. It is
now standard daily operating procedure to shut off the secondary effluent
pump for approximately 40 minutes each morning. During this 40 minute
period the air sparger is turned on for 20 minutes which breaks up the
solids contained within the tube clarifier. The air sparger is then
turned off and during the remaining 20 minutes the solids are allowed to
settle from the tubes.
205
-------
The flocculator was sized to provide a theoretical detention time of 15
minutes at a design flow rate of 235 gpm. Upon operation of the unit
poor floe formation was noted. A study was conducted in an attempt to
determine the cause. This study indicated that the actual detention time
was approximately eight minutes. In addition, it was noted that air bubbles
were being entrapped in the feed stream to the flocculator at the flow splitter
box which is located immediately upstream of the flocculator. The following
two modifications were made in an attempt to increase the actual detention
time and thus improve floe formation. First a plywood diffuser plate was
placed in the middle of the flocculator. Holes were drilled in the plate
and the plate was installed perpendicular to the vertical axis of the
flocculator. The surface area of the diffuser plate approached that of
the flocculator. Entrained air was eliminated from the flocculator by
insuring that the discharge pipe from the flow splitter box to the
flocculator was always submerged. This was accomplished by placing an
orifice plate over this discharge port. These two modifications increased
the actual detention time to approximately 12 minutes. These modifications
did assist in floe formation.
Following flocculation the waste stream flows by gravity to the tube-type
solids separator. While operating this tertiary equipment it appeared that
the chemical floe was being destroyed by the entrance conditions into the
solids separator. The original entrance conditions consisted of a straight
discharge from a pipe into a vertical headwall which was located about one
foot from the discharge end of the pipe. To modify this flow condition the
influent stream into the solids separator was redirected downward and parallel
to the headwall by placing a ninety degree elbow on the discharge end of the
influent pipe. This change in entrance configuration has assisted in
maintaining floe structure.
It was further noted that there appeared to be an incomplete utilization
of the solids storage capacity of the tertiary tube-type solids separator.
The portion of the tubes located near the inlet to the solid separator would
become full of solids earlier than those tubes located farther away. As a
result, discharge of solids from some tubes occurred before an appreciable
portion of the tube separator's solids storage capacity had been utilized.
This inefficient use of the solids storage capacity had an adverse effect
on the length of filter runs. No modification or testing of the Tualatin
solids separator was undertaken. However, the equipment supplier did perform
dye studies on similar equipment and results confirmed the inefficient use
of the solids storage capacity. Modification by placing baffles underneath
the tubes provided for more efficient use of the separator.
SAMPLING AND ANALYTICAL PROGRAM
Sampling stations, chemical and physical analysis, and the testing schedule
utilized during the evalution phase of the grant are shown in Table 2.
206
-------
NJ
O
Table 2. Sampling and Testing Schedule
Dry Weather Period (Months of August 1970 - November 1970 Inclusive)
(Months of May 1971 - October 1971 Inclusive)
Nitrogen Phosphorous Cl£ Demand
Plant
influent
Secondary
effluent
Tertiary
effluent
Aeration
basin
contents
Total Dis. Set. S
12* — 20
12 — 20
12 12 20
2 .. ..
SS
12
12
12
8
DO Alk.
- 4
- 4
8 4
8 -
pH °C Total NO^
20 20 12
12 — 12 12
20 20 12 12
20 20 --
(Ortho & Total)
12
12
12
—
(Break Pt) MPN
-
8
8 4
-
Sludge pond
supernatant
2 — 2
-------
Table 2. Sampling and Testing Schedule (Cont'd)
o
00
Plant
influent
S5S2S
Tertiary
effluent
Aeration
basin
contents
Wet Weather Period
BOD5
Total Dis. Set. S SS
12 — 20 12
12 — 20 12
12 12 20 12
2 — — 8
(Months of December 1970 -
DO Alk. pH °C
4 20 20
4 12 —
8 4 20 20
8 - 20 20
Nitrogen
April 1971 Inclusive)
Phosphorous Cl2 Demand
Total N03 (Ortho & Total) (Break Pt) MPN
4
4 4
4 4
-
4 -
4 - -
4 -
_
SVI
-
-
-
8
Sludge pond
supernatant
2 —
* Numbers refer to number of tests scheduled per month.
-------
All chemical analyses, with the exception of dissolved oxygen, were
determined on composite samples. Measured physical water quality parameters
were evaluated on grab samples. Chemical and physical analyses were
analyzed according to "Standard Methods for the Examination of Water and
Wastewater," 12th Edition.
Composite samples were collected manually during an eight hour operating
shift (8 a.m. - 5 p.m.) and were refrigerated upon collection. These
samples consisted of hourly grab samples composited in proportion to the
rate of flow.
Other tests and observations conducted during the evaluation phase of the
grant were: daily hydraulic effluent volume, hours per day of tertiary
operation, velocity profile within the aeration basin, and solids deposition
on the bottom of the aeration basin.
PLANT LOADINGS
Tualatin's waste treatment plant was designed for a hydraulic loading of
280,000 gals/day whereas the flow to the plant averaged 97,000 gals/day
during the 14 month monitoring period. A geometric frequency distribution
of the hydraulic loading observed during this period is illustrated by
Figure 2.
Daily BOD5 loadings ranged from 24 to 1500 Ibs with an average of 480 Ibs.
The design BOD loading, as shown in Table 1, was 700 Ibs/day. This
design value was exceeded on 20 percent of the samples collected during the
monitoring period.
A pet food processing plant was the largest industrial waste source discharged
to Tualatin's waste treatment facility. Incremental additions from the
processing plant can be estimated from the data in Table 3 and they amounted
to approximately 25," 50, and 75 percent of the flow, SS, and BOD^ respectively,
applied to the treatment plant during normal operation.
Table 3. Influence of Pet Food Processing Plant on STP Loadings
SS
(mg/1) (rng/1)
Proc. Plant Closed
(2 wks vac.) .075 340 180
Proc. Plant Operating
(2 wks prior & after vac.) -100 690 750
209
-------
I
3OO
d
01
O
8
LL
U
100
6O
30
10
10
93,000 MEDIAN
"XOOOARTTH. AVERAGE
50
t_
90
99
FREQUENCY DISTRIBUTION1o;o<
FIGURE 2 - GEOMETRIC FREQUENCY DISTRIBUTION OF DAILY INFLUENT FLOW
-------
PLANT PERFORMANCE
In operating the tertiary chemical-physical system many combinations of
flow rate, alum dosages and polyelectrolyte concentrations were evaluated
for their effect on SS and P removal. The various levels investigated are
shown in Table 4.
Table 4. Tertiary Operating Variables
Flow Rate, GPM 75 110 140 190
Alum Dose, mg/1 0 100 125 155
180 210 240
Polyelectrolyte, mg/1
Pre-settler 0 0.5 1.0 1.5
2.0
Pre-filter 0 0.03 0.06 0.1
Frequency distributions of SS (Figure 3) and BOD5 (Figure 4) concentrations
indicate the removal capabilities of the treatment facility. It should
be understood that the tertiary effluent frequency distributions include
all levels of operating variables (flow rate, etc.).
In Figure 3 the secondary effluent frequency distribution has an appreciable
change of slope at approximately the 90 mg/1 SS level. This break was caused
by the higher solids concentration levels discharged from the tube-type
clarifier prior to the installation of the air sparger system (as discussed
earlier).
Lower 8005 and SS removal efficiencies were observed through the secondary
biological system than would normally be expected. This was primarily caused
by the high solids concentrations discharged from the tube-type clarifier.
Overall treatment plant BOD5 and SS removals, influent to tertiary effluent,
averaged 98 and 99 percent, respectively, with an average final effluent
BOD5 concentration of approximately 8 mg/1 and SS level of 6 mg/1.
Figure 5 illustrates the effect that alum dose had on the removal of SS
and ortho-P through the tertiary chemical-physical system at a specific
flow rate. As is shown in this figure, ortho-P levels of less than 0.1 mg/1
were obtained at alum dosages of 240 mg/1. Effluent SS were reduced to 3
mg/1 with an alum dose of about 125 mg/1.
211
-------
1000r
.100
o
Q
8
UJ
QL
10
PLANT INFLUENT
4 70, MED IAN
530. ARITH. AVG
-- 86, (BASED ON MEDIAN)
79. (BASED ON ARITH.
AVG.)
SECONDARY EFLUENT
65, MEDIAN
110, ARITH. AVG.
°7oRs.T-98, (BASED ON MEDIAN)
-95, (BASED ON AVG.)
, (BASED ON MEDIAN)
99, (BASED ON AVG.)
10
TERTIARY EFFLUENT
NOTE:<7«RT c MEANS
°70l?EDUCTIpfJ INFLUENT
THROUGH SECONDARY
EFFLUENT
1.5, MEDIAN
5.5 ARITH. AVG.
98
I
FREQUENCY DISTRIBUTION, °A><
FIGURE 3- GEOMETRIC FREQUENCY DISTRIBUTION OF SUSPENDED SOLIDS
212
-------
1000
600
300
100
PLANT INFLUENT
.460, MEDIAN
530, ARITH. AVG.
%Rl-S-89, (BASED ON MEDIAN)
87, (BASED ON AVERAGE)
SECONDARY EFFLUENT
52, MEDIAN
, ARITH. AVG.
7oRS.T"88,(BASED ON MEDIAN)
88, (BASED ON AVERAGE)
6.1, MEDIAN
7.8, ARITH. AVG.
99, (BASED ON MEDIAN)
98, (BASED ON AVG.)
TERTIARY EFFLUENT
NOTE: %Ri-s MEANS ,„
% REDUCTION INFLUENT
THROUGH SECONDARY
EFFLUENT
50 90
FREQUENCY DISTRIBUTION, %<
FIGURE 4- GEOMETRIC FREQUENCY DISTRIBUTION OF BOD5
213
-------
TERTIARY FLOW RATE - 190 GPM
ORTHO-P04 as P
SUSPENDED SOUDS
LEGEND:
• SUSPENDED SOUDS
• ORTHO-P04AS P
80 16O 240
ALUM DOSE mg/l
FIGURE 5, EFFECT OF ALUM DOSE ON EFFLUENT SS AND P IfVELS
214
-------
Table 5 compares the final effluent with and without alum addition. The
data presented covers all ranges of flow rates through the tertiary system
along with all alum concentration investigated. Alum resulted in a 75,
40, 75, and 75 percent reduction in SS, total BOD5 and total and ortho-P
concentration, respectively, through the chemical-physical system.
Table 5. Tertiary Effluent
Suspended Solids
BOD^, Total
BOD5, Soluble
Total PO^ as P
Ortho PO^ as P
Without
Alum
(mg/1)
14.7
11.6
5.5
5.7
5.3
With
Alum
(mg/1)
3.5
7.0
4.7
1.5
1.3
SUMMARY
The objective to demonstrate the BOD, SS, and P removal capabilities of a
full scale automated chemical-physical tertiary treatment system treating
combined domestic and industrial waste was met. In fact, it was shown that
under correct operating conditions a high quality effluent could be obtained
from Tualatin's WTS.
The tertiary unit was definitely shown to be an excellent method of upgrading
effluent from activated sludge plants and modifications thereof. Extremely
high percent removal was obtained through the tertiary process even with
poor secondary effluent quality. The poor quality secondary effluent appeared
to be the result of the poor liquid-solids separation obtained in the tube-
type clarifier.
Data pertaining to the grant's other objectives have not been evaluated, as
yet. However, upon complete evaluation of all the data collected during
the monitoring phase of this grant many of the remaining objectives should
be fulfilled. Further data evaluation will be undertaken by the grantee's
technical consultant and as stated earlier, the final report on the grant
should be available for public dissemination during the fall of 1972.
215
-------
OCEAN ASSIMILATION OF FOOD RESIDUALS
by
Walter W. Rose*, Allen M. Katsuyama*, and
Richard W. Sternberg**
INTRODUCTION
In the East Bay there are six food processing plants which rely on a
common ha,uling company to pick up, transport and dispose of solid
residuals generated during the processing of fruits and vegetables.
Up to ten years ago, these waste residuals were being handled in a
sanitary landfill operation. This practice was adequate as long as
suitable area and sufficient dry waste in the form of domestic refuse
could be mixed with the food residuals.
Two problems hastened the need for the .development of an alternate
disposal method. First, production by the canneries increased with
a resultant increase in solid residuals, thereby causing an imbalance
between dry and wet waste at the disposal site. Second, the landfill
operation gradually moved to an area of high water table, resulting in
seepage of bay water into newly filled cells.
Beginning in I960, cannery waste primarily from the processing of
fruits was centrally collected, loaded on a barge and transported more
than 20 miles beyond the Golden Gate for discharge in ocean waters.
A total of four monitoring trips were made in I960 and 1961 to deter-
mine the effects of this discharge on the quality of the receiving waters.
The results of these trips indicated only a momentary depression of
certain water quality parameters.
As a result of increasing awareness of ecological problems, general
concern has been recently expressed about the use of marine waters
as a depository for waste materials. On November 4 and December 1,
1970, reports and presentations were made before the San Francisco
^Western Research Laboratory, National Canners Association, Berkeley,
California 94710
* '^Washington Research Laboratory, National Canners Association,
Washington D. C.
217
-------
Bay Region Water Quality Control Board by the State Department of
Fish and Game. These reports indicated that the San Francisco Bay
Area crab harvest had declined drastically during the past 10 years.
Since the crab larvae exist in planktonic forms for about 110 days,
during January to June of each year, the State Fish and Game biologist
recommended that all industrial waste discharges into the marine
environment be prohibited. However, it was stated that food residuals
were being discharged only between July and October of each year.
On December 22, 1970, the San Francisco Bay Regional Water Quality
Control Board adopted Resolution No. 70-100 which would prohibit the
disposal of cannery residuals into the ocean after November 1, 1971,
unless it could be demonstrated to the satisfaction of the Board that
such wastes would have no adverse effects on water quality. The dis-
charger was required to file by February 15, 1971, an outline for a
study into the effects of food processing solid residuals upon water
quality and upon protected beneficial uses.
Development of 1971 Study Program
On February 25, 1971, the San Francisco Bay Regional Water Quality
Control Board accepted the study outline which was prepared by the
National Canners Association on behalf of the Oakland Scavenger Com-
pany. A progress report was required by August 15, 1971, and a final
report submitted on October 15, 1971.
An outline of the proposed 1971 study is given below and is divided into
five sections.
I. Definition and Characterization of Waste
A. Description of Waste
B. Characteristics of Waste
1. pH
2. suspended solids
3. volatile solids
4. settleable solids
a. rate of settling
5. percent solids
6. total oxygen demand
7. chemical oxygen demand
8. biochemical oxygen demand
a. 15 minute immediate oxygen demand
b. short term oxygen up-take (6 hours)
218
-------
c. 5-day BOD
d. 20-day BOD
e. ultimate BOD
9. proximate analysis
a. protein
b. carbohydrate
c. crude fibre
d. fat
10. agricultural chemical residues
a. chlorinated hydrocarbons
b. organophosphates
11. 48 hour fish bioassay
12. heavy metals (cadmium, chromium, copper, lead,
mercury and zinc)
II. Ocean Monitoring and Sampling
A. Dispersion Pattern of Waste Field
1. depth (surface, 10 ft, 20 ft, and bottom)
2. width
3. length
4. aerial photograph
B. Receiving Water
1. pH
2. temperature
3. dissolved oxygen demand
4. total oxygen demand or approved tracer substitute
III. Statement Regarding The Status of By-Product Utilization and
Alternate Disposal Methods
IV. Statement Regarding The Pre-Treatment of Solid Residuals With
Regard To:
A. pH control
B. Biological Treatment
C. Solids Removal
V. Shoreline Inspection if needed
A committee comprised of canners, representatives from State regu-
latory agencies, the National Canners Association and the Oakland Sca-
venger Company was formed to implement and revise, if necessary, the
proposed 1971 study. Some changes were made in the program and will
be mentioned in the text.
219
-------
CHARACTERIZATION OF SOLID RESIDUALS
Peaches and pears are the two major fruits processed by the East Bay
Canneries. On a seasonal basis it is estimated that waste generated
from these two commodities constitute about 90% of the total amount of
those food residuals which are placed in the ocean waters.
The solid residuals produced from pear processing are composed mainly
of peel, core, stem and blossom end cuts. Approximately 80% of the
total quantity of pear residuals comes from these operations. The re-
maining solids consist of chip particles, fruit sorted out as being over
ripe or containing defective material unacceptable for canning.
Peach residuals consist mainly of over and under ripe fruit, culls or
undersized fruit and normal peaches diverted away from production as
a result of a California marketing order. These sources contribute approx-
imately 90% of the total peach waste. The remaining quantity is made up
of small particles and fruit removed from sorting belts as being unaccept-
able for canning.
Analysis of Solid Residuals
A summary of the data collected for the analysis of the solid residuals
is contained in Table 1. Data are presented for the minimum and maxi-
mum values found in the analysis of four separate samples. The analysis
was performed on fresh samples before the addition of dilution water at
the reservoir site. Results are expressed on a wet weight basis.
The data collected for the characterization of solid residuals was per-
formed on samples taken on July 30, August 6, August 12, and August
27, 1971. In late June fresh market peaches and pears were purchased
and used to develop procedures and analytical techniques. The fresh
market fruits were also used in running the first bioassay.
Figure 1 is a plot of the BOD of one solid residual sample with respect
to time. The five-day BOD is 69% of the 20-day BOD which indicates
the presence of easily oxidizable organic matter. The ratio between
the 5-day and 20-day BOD also indicates the absence of any substances
of a toxic nature to bacteria.
220
-------
Table 1. Physical and Chemical Characteristics of Food Processing
Solid Residuals
Parameter
PH
Suspended solids, ppm
Volatile suspended solids, ppm
Settleable solids, ml/L
Total
solids, ppm
Minimum
3.6
29,000
15,200
56
176,800
Maximum
3.7
35, 400
18,600
61
181,800
Chemical oxygen demand, ppm
Total
Jeris method
Standard method
oxygen demand, ppm
settled
mixed
185,000
192,000
143,200
199,100
197,500
207,900
152,000
213,200
Biochemical oxygen demand, ppm
15 -minute
6 -hour
5 -day
20 -day
ultimate BOD
1-day
3 -day
5 -day
7 -day
9 -day
11-day
13 -day
15 -day
17 -day
19 -day
21-day
,310
3, 900
82, 000
118,800
32,100
73,600
82, 200
85, 800
94,300
96, 100
96,700
111, 300
119, 900
121, 000
126,200
400
4, 400
88,000
128,000
36,700
77,000
88,000
91,300
99,800
101,000
104, 600
117,800
124, 200
125, 600
133, 000
Proximate analysis
protein, %
carbohydrate, %
crude fibre, %
fat, %
0.61
7.60
3.57
0.16
0.814
8.50
3.97
2. 30
221
-------
Table 1. (cont'd) Physical and Chemical Characteristics of Food
Processing Solid Residuals
Parameter Minimum Maximum
Agricultural chemical residues, ppm
chlorinated hydrocarbons 0.010 0.02
organophosphates 0.015 0.03
Heavy metals, ppm
cadmium 0.04 0.08
chromium less than 0.02 0.02
copper 0.01 0.04
lead 0.08 0.10
mercury 0.006 0.009
zinc 0.06 0.13
222
-------
BOD OF PEACH-PEAR SOLID RESIDUAL
132,975
125.646
,185
117,840
^x
E
o
CO
99,756
91,254
88,020
40-
20
0
20
5 10 15
DAYS
Figure 1. BOD of Peach-Pear Solid Residual
223
-------
The immediate oxygen demand, as measured by the 15-minute BOD value
has a maximum value of 400 ppm. As will be shown later, there is a di-
lution ratio of one part residual to 542 parts of ocean water which means
that the maximum oxygen demand placed on the receiving water is 0. 74
ppm. Also, when dilution of the residuals with bay water and sea water
is considered, the actual oxygen demand is less than 0. 74 ppm.
The analytical values for pesticide residues are very low and less than
that being permitted in the final product by the Food and Drug Administration.
DDT or its analogues were not detected in any of the samples analyzed.
A check with the field departments of the canners verified the fact that
growers did not use DDT during the growth of the products. Furthermore,
a check of the pesticides used by the growers indicated a definite shift to
the use of nonpersistent pesticides.
The pesticide analysis was performed with a Tracer Model 211 gas chroma-
tograph using an electron capture detector. The total concentration of
chlorinated pesticides was estimated by summation of the recorded peaks,
using aldrin as the reference compound. The organophosphates were
determined in a similar manner, using diazinon as the reference compound.
Of the known pesticides applied to the raw products during the growing
season, Kelthane was present in the greatest concentration of chlorinated
hydrocarbons. It is estimated that the maximum concentration of this
material was 0.008 ppm. For the organophosphates, diazinon and para-
thion appeared in equal concentrations of approximately 0. 0075 ppm. Non-
persistent carbamates such as sevin, ziram and maneb were extensively
used by the growers.
It was beyond the scope of this project to attempt to identify each of the peaks
recorded by the gas chromatography analysis. Those pesticides known
to have been applied to the raw product and known to be persistent were
looked for on the chromatograms. Some chromatographic peaks, in the
chlorinated hydrocarbons and organophosphate analysis, were questionable
and were most probably of a nontoxic nature. Therefore, it is reasonable
to believe that the values reported in Table 1 are on the high side and that
the actual levels are less than those reported.
224
-------
COLLECTION OF SOLID RESIDUALS
The solid residuals generated at the food processing plants are separated
from liquid waste by means of screens. The most commonly used screens
are of the flat, vibrating type containing 20 openings to the inch, commonly
referred to as 20 mesh screens. The separated solids are held in hoppers
until removed by a truck. In most instances, the solids are removed from
the hopper within one hour.
Solids from the canneries are hauled to a common site prior to the loading
of the barge. Figure 2 is a photograph of the solids being unloaded into
the first part of a two sectional reservoir.
Figure 3 is a view of the grinder in the foreground. In the background is
a drag conveyor which takes the waste after dumping and feeds it to the
grinder.
Figure 4 is an overall view of the reservoir site containing ground fruit
•waste solids. On standing, even for short periods of time, the ground
material separates into two phases. The insoluble materials accumulate
on the surface with free liquid below. Before the barge is loaded, city
water is pumped into the reservoir; recirculation pumps are turned on
to mix the liquid and solid phases.
Figure 5 is an overall view of the pipe from the reservoir connected to
the piping system on the barge. The barge is divided into four separate
compartments and each compartment contains a pump. A fifth pump on
the barge takes in sea water to further dilute the solids once the discharge
has begun.
The barge has an overall length of 165 feet, width of 40 feet and draft of
9 feet. When fully loaded it contains a net weight of 1040 tons. The barge
is line towed by means of a tug boat which moves at a minimum of 2-1/2
knots. During disposal of the residuals the minimum speed is normally
3 knots.
Dilution of Solids
After an estimated barge load of ground waste has accumulated in the
reservoir, city water is added primarily to improve the pumping charac-
teristics of the waste. The water volume is metered; a quantity of water
equal to 20 to 25 percent of the reservoir contents of ground waste is added,
thereby diluting the waste by a comparable factor.
225
-------
IJ
t J
'
I .
Figure 2. Unloading of Solids at Central Collection Site
-------
'-">^"•"" ^ •
. -_. «
--- .-« .-.*- > VjT
Figure 3. Grinding of Solid Residuals
Figure A. Overall View of Collection Site
227
-------
10
10
••Jt
Figure 5. Loading of Barge
-------
Once the barge is in the disposal area and ready for discharge, a pump
is started to take in and distribute sea water to the four waste compart-
ments. Thus, when the four compartment pumps are discharging, the
waste is diluted by an additional factor of 25 percent. At times during
the draw down of the barge, only two pumps are operated, in which case
there is a 50 percent dilution during discharge.
As previously indicated, the analysis reported in Table 1 is for waste as
delivered to the reservoir site. By considering the dilutions mentioned
above, the actual concentrations of substances, at the point of discharge,
are generally one half those reported in Table 1.
229
-------
MONITORING PROGRAM
A total of three monitoring trips were made during 1971. During the first
two trips water samples and data were collected before discharge and
during discharge at four distances behind the barge and at various depths.
On the third trip the monitoring vessel was initially positioned approxi-
mately 500 feet behind the barge. While the barge continued its normal
course, the monitoring vessel remained in this stationary location and
samples were collected from various depths with respect to time. Also
on this third trip, samples of floatables were collected with respect to
time.
A map of the disposal area and the various boundary lines are depicted
in Figure 6. Because food residuals are classified as garbage, it is
necessary for the barge to go beyond the 20-mile limit. The discharge
area, in addition to being beyond the 20-mile boundary, is also outside
the 3-mile State jurisdiction as applied to the Farallon Islands.
Prior to the first monitoring trip, a Rhodamine dye was added at the
reservoir site as the food residuals were being ground by the hammer -
mill. Sufficient dye was added to give a concentration of 10 ppm in the
barge when fully loaded. However, at the disposal area it was only possible
to detect a minimal dye concentration of approximately 2 parts per billion
(ppb) at the closest monitoring position (100 feet) behind the barge. This
is evidence that there is a high dilution and a rapid dispersion once the
material enters the ocean. The above value indicates a 5, 000-fold dilu-
tion of the material at a point 100 feet behind the barge.
On the third monitoring trip a concentrated dye was used to mark the
sampling field. When the sampling vessel was in position, a signal was
given and the dye was released from the stern of the barge. In addition
to using the dye as a means of marking the field, a floating buoy was
thrown overboard to be used as a guide by the monitoring vessel. How-
ever, the buoy was useful for only approximately 30 minutes, after which
time winds had caused it to drift out of the waste field.
The Marine Ecological Institute provided the vessel for use in the moni-
toring phase of the 1971 study. Personnel from the Institute were most
helpful in reviewing the objectives of the monitoring program and in
serving as part of the monitoring team. Planning sessions were held
aboard the monitoring vessel during each trip to the disposal area (Figure 7).
At this time additional work assignments, as well as an overall review
of the objectives of the trip, were made. An average of three hours
elapsed from the time of departure until arrival at the disposal site.
230
-------
! -.'
V
Gulf Limit
20 mi. Ln.
1" s 60 SI. Mi.
—~_ ^
DiichcTrJe —
'Area
PACIFIC OCEAN
Figure 6 Map of Disposal Area
-------
Figure 7. Planning Session on Monitoring Vessel
232
-------
Figure 8 shows the reading of the current meter after being in the water
for 10 minutes. The readings for velocity and direction of the ocean waters
found during the monitoring trips are summarized below:
2. 008 knots at 60°
1. 090 knots at 40°
1. 020 knots at 10°
Figure 9 is a photograph taken of the barge in the disposal area just prior
to the beginning of the discharge of solid residuals. The monitoring vessel
was manuevered into the correct position behind the barge as discharge
was commenced.
Figure 10 is a view directly behind the barge. On either side can be seen
the discharge pipes submerged below the water surface. Each pipe extends
5 feet below the surface when the barge is empty. With a fully loaded
draft of 9 feet, the pipes are 14 feet below the water surface.
Submerged discharge of the food residuals was first provided in 1971; the
previous mode of disposal had been surface discharge. The data and ob-
servations collected during 1971 supported the contention that this change
significantly improved the disposal operation by providing a greater dilu-
tion of the waste within the receiving waters and resulting in less floating
material and less water discoloration.
A TDC instrument (Figure 11) was used to collect temperature, depth, and
conductivity data. With well-established correlation factors, conductivity
readings were readily converted to salinity.
Water samples were collected with Van Dorn bottles. By affixing three
bottles to appropriate points on a weighted cable (Figure 12), simultaneous
samples were collected from three different depths. Waters from these
samplers were transferred into BOD bottles (Figure 13) for dissolved
oxygen determinations and to reagent bottles for pH measurements
(Figure 14) and other analyses. With the exception of total organic car-
bon, all analyses were conducted aboard the research vessel shortly
after each sample had been collected.
The data collected from the first two monitoring trips are summarized in
Tables 2 and 3. During these trips water samples were collected at vari-
ous distances behind the barge and from several depths at each distance.
Although water samples were drawn from a 200-foot depth, the TDC in-
stument was limited by its cable length to 80 feet.
233
-------
Figure 8. Reading of Current Meter
234
-------
I
Id
Ln
Figure 9. Barge on Location in Discharge Area
-------
IJ
OJ
>
Figure 10. Aft View of Barge
-------
Figure 11. Taking TDC Reading
237
-------
Figure 12. Attaching Samples to Cable
238
-------
Figure 13. Filling of BOD Bottle After
Sample Collection
239
-------
Figure 14. pH Determination On-Board
Monitoring Vessel
240
-------
Table 2. Ocean Monitoring Data: August 6, 1971
Distance
ft
100
500
1000
2000
100
500
1000
2000
100
500
1000
2000
100
500
1000
2000
100
500
1000
2000
Temperature, °C
Depth -- inside fie Id
Depth -- outside field
10' 20' 40' 80' 200' 1'
10' 20i 40' 80' 200'
13.2 12.3 10.8 --- - ---
13.5 12.8 12.0 11.9 9.8 13.2 12.8 12.4 11.9
13.1 12.3 11.0 10.9 10.8 13.0 12.8 12.5 11.8
13.4 13.0 12.8 11.0 10.0 13.3 12.5 12.0 10.4 10.8
Conductivity, mmhos/cm
22.8 25.0 25.9
25.0 30.3 27.9 23.1 29.1 30.0 31.6 30.9 30.9
33.2 30.9 31.2 26.1 26.4 31.6 31.6 31.6 30.0 ---
28.5 25.0 21.8 28.5 29.1 32.3 30.9 30.3 29.1 28.8
Salinity, ppt
18.4 21.0 21.4 _--
20,1 25.3 23.6 18.4 26.2 24.9 26.0 26.0 26.4
27.8 26.1 27.4 22.5 22.8 26.2 26.2 26.5 25.8
23.4 20.5 17.6 24.8 26.0 26.7 26.0 26.0 25.7 25.1
pH Units
7.95 7.9 7.8
7.6 7.9 8.1 8.0 8.1 8.0
7.7 7.9 7.8 7.9 7.6
7.8 8.0 8,0 8,0 7.9 7.8 8.1 8.1 8.1
Dissolved Oxygen, ppm (Winkier)
9.3 9.1 6.1
9.0 10.3 9.7 9.6 9.6 9.5
9.0 8.4 4.3 ---
9.1 9.0 9.3 9.6 7.1 5.0 9.1 9.6 9.6
241
-------
Table 2. (cont'd) Ocean Monitoring Data: August 6, 1971
Turbidity, % Transmission
Depth -- inside field Depth -- outside field
Distance
ft* 1' 10' 20' 40' 80' 200' 1' 10' 20' 40' 80' 200'
100 98 98 99
500 93 97 97 99 98 98
1000 95 97 95 97 98
2000 98 97 98 98 98 100 98 99. 99 -
#Refers to distance between barge and monitoring vessel at time of data
collection
242
-------
Table 3. Ocean Monitoring Data: August 12, 1971
Temperature, C
Depth -- inside field
Distance
ft*
100
500
1000
2000
100
500
1000
2000
100
500
1000
2000
100
500
1000
2000
100
500
1000
2000
1' 10' 20' 40' 80' 200'
10.7 11.7 11.6 11.2 11.2 ---
11.5 11.5 11.3 11.0 10.3 ---
11.5 11.5 11.5 11.2 10.4 ---
11.8 11.5 11.4 11.0 10.3 ---
Conductivity, mmhos/cm
28.5 28.2 28.2 30.9 29.7 ---
31.6 30.9 32.3 30.9 30.0 ---
29.1 28.2 27.9 30.9 30.3 ---
29.4 30.0 30.9 30.9 30.3 ---
Salinity, ppt
25.0 24.0 24.0 26.9 26.4 ---
27.3 27.0 28.3 27.2 26.9 ---
25.2 24.2 24.2 27.2 26.9 ---
25.0 26.0 26.0 27.1 27.0 ---
pH Units
7.50 7.80 7.95 7.50 7.50---
7.75 7.90 7.90 7.60 7.80---
7.50 7.60 7.80 7.85 8.00 7.
7.85 7.85 7.90 7.50 7.40 7.
Dissolved Oxygen, ppm (Winkler)
9.2 9.0 9.1 8.8 8.0 ---
9.1 8.6 8.6 9.7 8.0 ---
8.9 8.8 8.8 8.7 8.7 2.
8.8 9.0 9.0 9.0 9.7 8.
_
-
-
-
-
-
_
-
-
-
-
65
50
-
1
4
Depth -- outside field
_T|
11.7
11.4
11.5
11.8
10'
11.6
11.4
11.5
11.8
20'
11.5
11.3
11.3
11.8
40'
11.2
11.0
11.4
11.3
80'
10.5
10.5
11.3
11.0
200'
33.6 33.. 6 34.4 29.1 31.2
33.6 34.4 34.4 31.6 31.6
29.7 28.5 29.7 33.4 33.6
32.8 34.4 33.6 32.8 33.2
29.2 29.2 30.2 25.4 27.8
29.5 30.0 30.0 27.8 28.2
25.7 24.6 25.8 29.2 29.3
28.5 29.7 29.0 29.0 29.4
7.50 7.70 7.65 7.75 7.90
7.55 7.85 8.05 7.90 7.50 7.40
7.60 7.80 7.80 7.65 7.85 7.55
7.40 7.65 7.65 8.00 8.05 7.80
9.1 9.0
9.3 9.3
8.9 8.9
8.8 8.8
9.0
9.7
8.8
8.7
8.8
9.1
9.4
9.4
8.7
8.5 3.7
9. 3 4.0
9.6 4.9
* Refers to distance between barge and monitoring vessel at time of data
collection
243
-------
The parameters listed in Tables 2 and 3 are all interrelated and, as such,
should reveal differences between samples collected inside and outside
the waste field whenever the discharge of food processing residuals sig-
nificantly affected the receiving water. Of these parameters, temper-
ature would expectedly be the least indicative since the differential be-
tween the ocean waters and the food residuals would be small. Turbidity
would probably be the next least likely indicator since the method lacks
sufficient sensitivity. However, changes in conductivity or salinity, pH
and dissolved oxygen would most readily be observed if there is an effect
of the discharge on the receiving water.
The data for the two monitoring trips of August 6 and 12, 1971, did not
show a consistent pattern for changes of conductivity or salinity, pH,
and dissolved oxygen. When differences between samples collected in-
side and outside the field were noted, these differences were small.
Also, when these differences were noted, the persistence was of a short
duration.
On the first monitoring trip, several samples from different distances
and depths were not collected. The failure to collect a higher percent-
age of samples can be attributed to lack of experience and occasional
failure of the water sample collection system. On the second trip, very
few of the designated samples were omitted, primarily as a result of ex-
perience gained from the first trip.
The advisory committee reviewed the data collected from the first two
monitoring trips. After a thorough discussion, it was concluded that a
third trip would be necessary and that the approach in evaluating the dis-
charge of food processing residuals should be modified.
The primary objective of the third trip was to evaluate the temporal
changes in the quality of the receiving waters at a prescribed stationary
location. The first two trips were designed to ascertain the degree of
any immediate effects on the receiving waters, whereas the third trip
was made to determine whether any prolonged changes were created as
a result of the discharge. The purpose and procedure of the third moni-
toring trip are described below.
Third Ocean Monitoring Trip, August 27, 1971
Purpose: 1. Determine the quality of sea water prior to the dis-
charge of food processing solid residuals.
2. During the discharge of food processing solid resi-
duals, determine the immediate effects of the dis-
charge on the quality of ocean water while sampling
244
-------
at a stationary site with respect to the discharge.
3. Determine the concentration of floating food processing
solid residuals with respect to time from a stationary
location.
Procedure: I. Before Discharge
A. Make four water column profiles at 10 foot
increments to a depth of 90 feet and determine
temperature, salinity and conductivity.
B. Make two water column profiles at 1, 10, 20, 40,
80 and 200 foot depths and one profile at 10 foot
increments to a depth of 200 feet and determine
pH, dissolved oxygen and total organic carbon.
II. During Discharge
A. Mark the waste field by discharging a concentrated
solution of dye (Rhodamine B) while the barge is
discharging solid waste residuals.
B. Move monitoring vessel into the waste field
and at a distance approximately 500 feet be-
hind the barge. Stop engines and begin sampling
program. Manuever vessel as required to
remain within wastefield.
C. At 12 minute intervals and for a period of one
hour, collect samples and data at 1, 10, 20, 40
and 80 foot depths. Determine temperature, .
salinity, conductivity, pH, dissolved oxygen,
Rhodamine dye, and total organic carbon. At
the end of one hour make a water column pro-
file study at 10 foot increments to a depth of
200 feet and determine pH, dissolved oxygen,
Rhodamine dye and total organic carbon.
III. Surface Grab Samples
A. At time intervals of 1. 5, 3, 5, 10, 15, 45 and
60 minutes collect four one gallon grab samples
245
-------
from the water surface. Composite the grab
samples and remove a one liter sample for
analysis. Blend the one liter sample and
analyze for total organic carbon and Rhodamine
dye.
Tables 4 through 10 represent data collected from the third monitoring
trip. Following the tables, two graphs illustrate some of the more per-
tinent data collected from the monitoring trip.
Tables 4, 5, and 6 represent data collected at the disposal area prior to
discharge. Tables 7, 8, and 9 are data collected after discharge. Table
10 is data for the surface skimmings and indicates the quantity of floatables
present at the stationary location.
246
-------
Table 4. Summary - - Ocean Monitoring Trip August 27, 1971--Before
Discharge
Parameter Series
Temp
°C
Salinity
Percent
Conductivity
mmho / cm
1
2
3
4
1
2
3
4
1
2
3
4
1
16.3
16.3
16.5
16.5
3.10
3.06
2.90
2.92
39.8
39.8
38.9
38.2
10
16.3
16.3
16.5
16.5
3.10
3.06
2.90
2.92
39.8
39.8
38.9
38.2
20
16.0
16.0
16.2
16.2
3.12
3. 00
2.90
2.94
39.8
38.2
38.9
38.2
Depth
30
15.2
15.5
15.3
15.1
3.08
2.98
2.94
2.95
38.2
37.3
37.3
37.3
of Sample in Feet
40
13.8
14.3
14.0
13.9
3.10
2.97
3.01
2.95
36.6
36.6
36.6
35.9
50
13.0
13.5
13.2
13.5
2.98
3.04
2.96
2.92
35.8
35.8
35.0
34.4
60
12.3
13.0
13.0
13.0
2.98
3.00
2.94
2.94
35.0
35.0
35.0
34. 4
70
11.5
12.3
12.0
12.1
2.96
2.96
2.94
2.88
33.6
34. 4
34. 4
33.6
80
11.2
11.4
11.2
11.3
2.89
2.88
2.96
2.84
32.8
32.8
33.6
32.8
90
11.2
11.2
11.2
11.2
2.84
2.86
2.96
2.86
32.3
32.3
33.6
32.3
Table 5. Summary -- Ocean Monntoring Trip August 27, 1971 -- Before
Discharge
Parameter
pH
D.O.
ppm
Total
Organic
Carbon
ppm
Series
1
2
3
1
2
3
1
2
3
1
7.7
8.0
8.0
8.10
8.10
7.80
27
22
22
Depth of Sample in
10
7.8
8.0
8.1
7.95
7.50
8.20
25
28
26
20
7.9
8.1
8.1
7.60
7.30
8.21
24
28
25
40
7.9
8.0
7.9
8. 40
8.25
8.30
26
24
31
80
8.0
8.0
7.9
8. 60
8.50.
8.55
27
26
27
Feet
200
8.0
8.0
7.9
7.80
7.45
7.20
25
24
26
247
-------
Table 6. Summary -- Ocean Monitoring Trip August 27, 1971 -- Before
Discharge
Parameter Water Column Profile Study -- Depth in Feet
10* 20 30 40 50 60 70 80 90 100
_1 110 120 130 140 150 160 170 180 190 200
pH 7.7 7.8 7.9 8.0 7.9 8.0 8.0 7.9 8.0 8.0 8.0
8.0 8.0 7.9 7.9 7.9 8.0 7.9 8.0 7.9 8.0
D.O. 8.10 7.95 7.60 7.65 8.40 8.30 8.50 8.60 8.60 8.10 8.00
ppm 7.50 7.75 8.40 8.00 8.40 7.60 7.75 7.10 7.40 7.80
Total 27 25 24 25 26 25 26 28 27 27 33
Organic 35 27 31 26 40 27 28 25 24 25
Carbon
ppm
* The top value for each parameter refers to depth as indicated on the first
horizontal line. The second value refers to depth as indicated by the
second horizontal line.
248
-------
Table 7. Summary -- Ocean Monitoring Trip August 27, 1971
During Discharge
Parameter Mins.
Temp.
°C
Salinity
Percent
0
Depth in Feet
10
20
40
80
0
12
24
36
48
60
17.0
16.5
16.5
16.7
16.8
16.9
17.0
16. 5
16.5
16.7
16.6
16.8
16.7
16.5
16.5
16.3
16.6
16.5
15.1
15.0
14.5
14.5
14.9
14.9
12.5
12.3
12.5
12.0
12.3
12.9
2.74 2.76 2.86 2.94 2.92
12
24
36
48
60
3.02
2.96
3.02
3.00
3.02
3.02
2.96
3.00
3.01
3.02
3.02
2.96
2.90
2.96
3.00
2.96
2.92
2.94
2.95
2.95
2.86
2.94
2.98
2.84
2.92
Conductivity
mmho/cm
60
38.9 37.3 34.4
38.2 36.6 33.6
38.2 35.8 34.4
37.3 36.2 34.4
38.2 36.6 33.6
39.4 39.4 38.9 36.6 33.6
0
12
24
36
48
38.2
38.2
38.2
38.9
38.9
38.9
38.2
38.2
38.2
38.9
The barge was towed at a speed of three knots, which is equivalent to
5, 456 meters per hour, or 91 meters per minute, or 300 feet per minute.
The first samples were collected approximately 1.5 minutes after dis-
charge began, which represents a distance of 450 feet behind the barge.
Therefore, the stationary sampling location in relation to the moving
barge for the different time intervals is as follows:
0 mins = 450 feet
24 mins = 7, 200 feet
48 mins = 14, 400 feet;
12 mins = 3, 600feet
36 mins = 10,800 feet
60 mins - 18, 000 feet
249
-------
Table 8. Summary -- Ocean Monitoring Trip August 27, 1971
During Discharge
Parameter
pH
D. O.
ppm
Rhodamine
ppb
Total
Organic
Carbon
ppm
Mins.
0
12
24
36
48
60
0
12
24
36
48
60
0
12
24
36
48
60
0
12
24
36
48
60
Depth in Feet
1
7.
7.
7.
7.
7.
8.
7.
7.
6.
7.
8.
8.
3.
2.
12.
2.
0
0
60
45
37
29
33
32
4
7
6
9
9
1
55
73
60
70
00
00
3
0
3
0
10
7.
7.
7.
7.
8.
8.
7.
7.
7.
8.
8.
7.
3.
7
9
9
9
0
1
60
90
05
00
35
95
3
1.0
1.0
0
0
0
66
27
26
25
20
27
20
7.8
8.0
8.0
8.1
8.1
8.1
8.10
8.00
8.10
8.30
8.00
8.00
1
0
1
0
0
0
29
27
28
25
25
24
40
8.
8.
0
1
8.0
8.
8.
8.
7.
9.
8.
8.
7.
8.
1
0
1
0
0
0
26
26
27
20
25
25
1
1
1
80
20
00
20
60
30
80
7.9
8.1
8.1
8.1
8.1
8.1
8.40
8.90
8.50
8.40
8.80
0
0
0
0
0
0
27
27
33
26
25
29
200
8.
8.
0
0
8.0
8.
8.
8.
8.
8.
8.
8.
8.
8.
0
0
0
0
0
0
26
25
25
26
24
27
1
0
1
10
90
25
75
50
20
250
-------
Table 9. Summary -- Ocean Monitoring Trip -- August 27, 1971
Water Column Profile 60 Minutes After Discharge
Depth in
Parameter
PH
D.O.
ppm
Rhodamine
ppb
Total
Organic
Carbon
ppm
10*
1 110
8.0 8.0
8.1
8.4 8.9
8.6
0 0
0
24 26
28
20
120
8.1
7.9
9.0
8.5
0
0
26
29
30
130
8.1
7.9
_ « —
8.6
0
0
25
28
40
140
8.1
7.9
8.5
8.6
0
0
30
27
Feet
50
150
8.1
8.0
8.1
8.5
0
0
25
29
60
160
8.1
8.0
8.6
8.8
0
0
27
26
70
170
8.1
8.0
8.0
8.5
0
0
24
26
80
180
8.1
8.0
8.6
8.7
0
0
25
28
90
190
8.1
8.0
8.4
8.8
0
0
28
22
100
200
8.1
8.0
9.0
8.3
0
0
24
27
* The top value for each parameter refers to depth as indicated on the
first horizontal line. The second value refers to depth as indicated by
the second horizontal line.
Table 10. Summary -- Ocean Monitoring Trip -- August 27, 1971
Surface Grab Samples
Time in Minutes
Parameter 1.5 3.0 5.0 10.0 15.0 30.0 45,0 60.0
Total
Organic 56 58 144 42 37 70 45 37
Carbon ppm
Rhodamine 578221 00
ppb
251
-------
Figures 15 and 16 graphically illustrate some of the data collected from
the third monitoring trip. The data for pH and total organic carbon are
very similar in illustrating the momentary change as a result of the dis-
change and the rapid recovery in the quality of the receiving water.
The most noticable pH effect was observed in the initial samples. How-
ever, between 20 and 40 feet and greater depths, there was no detectable
effect. After 24 minutes the pH change relative to the natural pH was
limited to only a depth of less than 10 feet. Beginning with the 36 minute
sample, there were no further detectable pH differences between the
water before and after discharge.
Regarding total oxygen demand, the same comments as those noted for
pH apply. The data collected from the third trip give every indication
that the discharge of food processing residuals will change certain water
quality characteristics a slight degree, but that there is a rapid return
to the natural characteristics and that there are no prolonged effects.
Two arrangements were made to have aerial photographs taken as the
barge was discharging. On both occasions overcast weather prevented
the photographing of the operation. The primary objective of the photo-
graphic mission was to provide an indication of the extent of the surface
waste field. We believe the data collected from the three monitoring
trips can be used in determining the extent of the waste field.
252
-------
8. 1 60 Min
8.0
7.9
7.8
7.7
7.6
7.5
7.4
48 Min.
36 Min.
12 Min.
24 Min.
0 Min.
Range in pH of
receiving water
before discharge
1 10 20 40 80 200
DEPTH IN FEET
Figure 15 Correlation ot Depth and Time with pH
253
-------
70_
u
O
OMIN.
Range in TOC of
receiving water
before discharge
10 20 40 80 200
DEPTH IN FEET
Figure 16 Correlation of Depth and Time with Total Organic Carbon
254
-------
FISH BIOASSAY
A memorandum from the State Department of Fish and Game to the
Regional Water Quality Control Board, San Francisco Bay Region,
dated April 26, 1971, outlined the bioassay procedure and the method
to be used in establishing the ratio of solids to water.
The advisory committee was again called upon to work out the details
of the test procedure which is presented below.
Materials and Supplies
1. Test aquaria - 55 gallon steel drums with polyethelyne liners and
PVC piping.
2. Test species - shiner perch.
3. Sea water from Steinhart aquarium
Test Conditions
1. Salinity - approximately that of the receiving water.
2. Temperature - a constant 15°C.
3. Aeration - none except that caused by turbulence in the test tank.
4. Concentration of the sediment - for amount of sediment used,
drained but not saturated wet volume.
5. Test concentrations - control plus volume ratios of solids at 1, 3,
and 10 times those ratios predicted in the disposal area according
to the following rationale:
a. Calculate the cubic meters of solids to be released
into the disposal area during a single disposal operation.
b. Calculate the surface area in square meters to receive
solids during a single operation and multiply this value
by the depth of the area in meters or by 3, whichever
value is less.
255
-------
c. The ratio of No. 1 to No. 2 (volume of solids to
volume of area receiving solids) may represent
the basic test concentration for bioassay. For
other concentrations multiply the volume of solids
by 3 and 10.
Bioassay Procedure
1. Calculate volumes of water and solids to give desired test con-
centrations at a total volume of 150 liters.
2. Mix solids and water in test container to 150 liters.
3. Turn on recirculation pump.
4. Introduce a minimum of 10 test fish to each test container. Only
one species may be used for a series of bioassays. Test specimens
should be of equal size and should not exceed a total weight of 150
grams.
5. After one hour of operation withdraw water sample for determination
of:
a. Dissolved oxygen
b. pH
c. Turbidity
d. Temperature
e. Suspended solids
6. Repeat of No. 5 each 12 hours.
7. Record number of deaths at 12-hour or less intervals.
8. Bioassay shall run for a minimum of 48 hours.
9. Report number of deaths and results of chemical analyses for
12-hour intervals.
10. Make a tabular comparison of results for control and three
concentrations of sediment.
256
-------
The data used in calculating the basic concentration or ratio of residual
to water are as follows:
1. Barge Dimensions
a. Length = 165' (50.3m) d. Load (Net) = 1040 tons
b. Width = 40' (12. 2m) e. Volume of waste = 1658m3
c. Draft = 9' ( 2.7 m)
2. Receiving Water Volume
a. Width = 60' (18.3 m)
b. Depth = 10' ( 3.1 m)
c. Length =
Barge speed = 3 knots 3 knots x 1852 m/hr x 3 hrs
Discharge duration = 3 hrs = 16, 700 m
d. Volume:
18 m x 3 mx 16,700 m = 9. 02 x 105 m3
3. Basic Test Concentrations
a. Volume ratio:
1.66 x 103 . _ . ._ 3 1
———5= 1.84x10-^ or —
9.02x 10° 542
b. Weight to volume ratio:
2, 080, OOP Ibs _ 2. 3 Ibs
902,000 m-3 ~ m3
4. Test Concentration (basic)
a. By volume: @ 40 gallons sea water
40
waste volume =
O ^Tu
= .074 gallon
280 ml
b. By weight to volume:
40 gallons = .152 m3 (.00379 m3/gal)
weight of water = 2. 3 lbs/m3 x . 152 m3
= 0.35 Ibs/40 gallons
257
-------
5. Specified Test Conditions
a. Basic concentration (Ix) - 0.35 lbs/40 gallons
b. Three times basic (3x) = 1.05 lbs/40 gallons
c. Ten times basic (lOx) t= 3. 50 lbs/40 gallons
Figure 17 is a schematic drawing of the test aquaria. The test tank is
a 55 gallon, 18 gauge, steel drum. Four mil polyethylene bags, 38" x 65",
were used as liners. Two liners were used in each drum. All the
piping, as well as pump parts that come in contact with water, were
constructed from polyvinyl chloride (PVC). To protect the pump intake,
a fiberglass tray was constructed and placed at the bottom of the drum.
Small holes (1/4") were drilled into the tray to allow free passage of
water through the pump. For the first bioassay, a plastic scouring pad
was placed over the pump intake at the bottom of the barrel. (The plastic
tray, described above, was not used in this first experiment. ) The
purpose of the tray or pad was to prevent the fish from being sucked
up into the recirculation system.
The conditions, variables and results of the first bioassay are given
in Table 11.
The test run was terminated after 28 hours with all fish in the control
surviving and all other fish dead. Two problems in this experiment
were encountered. First, the filter or scouring pad over the pump
inlet became clogged and reduced the recirculation flow. Second, sub-
surface discharge did not provide sufficient oxygenation to meet the
demand exerted by the solid residuals.
To overcome the problem of clogging of the pump intake, it was necess-
ary to use another method. It was decided for the next bioassay to use
the fiberglass tray as previously described. Figure 18 is a photograph looking
down into a test tank. The fiberglass tray with perforated holes can
be seen at the bottom.
In the second bioassay, efforts were made to satisfy the oxygen demand
by having the discharge end of the recirculation system spray the water
up into the air and splash along the inside of the barrel. Figure 19 is
a photograph showing the recirculation system discharging above surface
on the left, and the submerged discharge as used in the first bioassay
on the right.
258
-------
SAMPlf
OUTLET
V. r
PUMP
f\
*.'
NG"
'ION
-
1
FIBERGLASS PLATE
1
40 GALLON
WATER LEVEL
*_ 55 GALLON DRUM
POLYETHYLENE
.LINER
Figure 17 Schematic of Test Aquaria
259
-------
Table 11. Fish Bioassay No. 1 July 21-22, 1971
Conditions
1.
2.
3.
4.
5.
6.
7.
Test fish - shiner perch, 10 per barrel, average weight,
15 grams.
Water - sea water from Steinhart Aquarium, 40 gallons
each barrel.
Test container - 55 gallon steel drum with two polyethylene
bag liners.
Temperature - 15°C.
Waste - ground peach-pear.
Plastic scouring pads over pump inlet.
All barrels had recirculation pump discharge below surface
of water.
Variables
1. Barrel No. 1
2. Barrel No. 2
3. Barrel No. 3
4. Barrel No. 4
5. Barrel No. 5
control
0. 75 Ibs of solids
2. 25 Ibs of solids
2. 25 Ibs of solids
5. 75 Ibs of solids
Results
Barrel No.
1
2
3
4
5
1
2
3
4
5
1
2
3
4
5
Hours
1
1
1
1
1
6
6
6
6
6
28
28
28
28
28
Dissolved
Oxygen, ppm
7.0
6.5
5.4
6.1
3.9
6.4
3.9
4.1
3.5
3.1
7.3
0.0
0.0
0.0
1.1
Suspended
Solids, ppm
10
30
149
191
356
pH
5
23
192
59
53
7.5
7.0
6.5
6.6
6.1
7.5
6.9
6.5
6.6
6.1
7.4
6.2
5.6
5.7
6.1
260
-------
Figure 18. View Looking Down into Test Tank
Figure 19. Above and Below Surface Discharge of
Recirculation System
261
-------
The conditions, variables, and results are tabulated in Table 12.
The test ran for the prescribed 48 hours, then was terminated. After
24 hours, all of the fish in barrel No. 1 were dead, and one dead fish
in barrel No. 2 was noticed. At the end of the 48 hours, a fish count
was again made in barrel No. 2 with all remaining fish alive.
The pH in barrel No. 2 was adjusted after the 30-hour sample had been
collected. The pH had dropped to a value of 4. 6 and would have continued
to drop as the carbohydrates in the solids fermented. To eliminate
possible side effects caused by the pH during the test period, sodium
hydroxide was added to bring up the pH.
In this experiment, the previous one, aid those that followed, it was
impossible to see the fish in the tanks after solids had been added. The
visibility was limited to only a few inches of depth. Several efforts were
made to devise a means for counting the fish during the test period.
One method which was partially successful was to use a submersible
high-powered flashlight. The final fish count was accomplished at the
end of the test period by draining the water from the drums and counting
the survivors.
Following the results of the second bioassay in which it was demonstrated
that the oxygen demand could be satisfied by using above-surface dis-
charge, a third bioassay was set up using three concentrations or ratios
of waste to water, a control, and a comparison again between surface,
and subsurface discharge of the recirculation system.. The conditions,
variables, and results are given in Table 13.
The results again confirmed the previous test findings in that the use
of a submerged discharge was not adequate to meet the oxygen demand
of the system. This deficiency was overcome by discharging above the
surface. It was not necessary to neutralize with hydroxide during the
test period, although after 48 hours, the pH in barrel No. 5 had dropped
to a value of 4. 5.
Following these three bioassays, a meeting was held to discuss the
findings. Concern was expressed that re-aeration through discharge
above the surface would result in the loss of volatile compounds from
the test container. Although it was pointed out that food processing
residuals contain only a very small percentage of volatile compounds
and that none of these were toxic, it was agrceded that a bioassay
262
-------
Table 12. Fish Bioassay No. 2 July 26-28, 1971
A. Conditions
1. Test fish - shiner perch, 10 per barrel, average weight,
15 grams.
2. Water - sea water from Steinhart Aquarium, 40 gallons
each barrel.
3. Test Container - 55 gallon steel drum with two polyethylene
bag liners.
4. Temperature - constant 15°C.
5. Waste - 5.6 pounds of ground peach-pear.
6. Filter - pump inlet enclosed inside plastic tray.
B. Variables
1. Barrel No. 1 - submerged 3 inches below water surface.
2. Barrel No. 2 - discharge above surface.
C. Results
Dissolved
Barrel No. Hours Oxygen, ppm pH
7.8 7.5
7.8 7.5
7.2 6.6
7.4 6.8
6.4 6.4
7.1 6.6
5.0 6.2
6.0 6.7
2.4 5.1
4.6 5.2
4. 0 4. 6
5.7 4.7
4. 9 4. 4
6.2 8.8
6.5 4.4
6.5 6.5
263
1
2
1
2
1
2
1
2
1
2
1
2
1
2
1
2
0
0
1
1
6
6
12
12
24
24
30
30
36
36
48
48
-------
Table 13. Fish Bioassay No. 3 September 5-7, 1971
A. Conditions
1.
2.
3.
4.
5.
6.
B. Variables
Test fish - shiner perch, 10 per barrel, average weight
15 grams.
Water - sea water from Steinhart Aquarium, 40 gallons
each barrel.
Test container - 55 gallon steel drum with two polyethylene
liners.
Temperature - constant 15°C.
Waste - ground peach-pear solids.
Filter - pump inlet enclosed inside plastic tray.
Location of the recirculation pump discharge and amounts of waste
in each barrel.
Barrel No.
2
3
4
5
6
Lbs of Waste
0.634
1.. 90
6.34
6.34
6.34
Control
1.90
Pump Discharge Location
Submerged recirculation
outlet
Above surface
ti
Submerged recirculation
outlet
Above surface
C. Results
Barrel
No.
1
2
3
4
5
6
7
Hrs
0
0
0
0
0
0
0
Oxygen,
ppm
8.1
8.05
7.9
7.9
8.0
8.3
8.2
Solids,
pH PPm Turbidity Remarks
...
•
•
264
-------
Table 13. Fish. Bioassay No. 3 (continued)
C. Results (continued)
Barrel
No.
1
2
3
4
5
6
7
1
2
3
4
5
6
7
1
2
3
4
5
6
7
1
2
3
4
5
6
7
Hrs
1
1
1
1
1
1
1
14.5
14.5
14.5
14.5
14.5
14.5
14.5
24
24
24
24
24
24
24
48
48
48
48
48
48
48
Oxygen,
ppm
7.9
7. 1
6.35
6.9
7.0
7.95
8. 0
0.5
0.2
0.4
5.3
5.9
5.7
7.6
0
0
0
2.3
2.7
4.5
7.4
0.2
0.3
0.0
3.0
4.6
4.0
7.5
pH_
7.5
7. 1
6.25
6.9
6.8
7.75
7.4
6.7
6.5
6.0
6.8
7.0
7.5
7.4
6.1
4.8
5.0
6.4
6.4
7.3
6.9
6.1
4.5
4.3
6.0
4.5
7.0
7. 1
Solids,
ppm
88
136
310
136
332
16
98
64
208
312
260
460
12
144
44
136
228
232
316
9
86
Turbidity Remarks
65
112
280 2 fish dead
240
250
< 25
90
60
140
310
260
300
< 25
130
130
180
270
350
360
< 25
120
57 10 fish dea.
150 10 fish dea.
300 10 fish dea.
350 5 living, 7
300 7 living, 3
< 25 11 living
90 12 living
dead
dead*
* One of the 3 counted as dead had died just after the conclusion
of the test.
265
-------
would be run with submerged discharge and some other method of
re-aeration.
It was suggested that oxygen be bubbled into the water as a means
of satisfying the oxygen demand. Figure 20 is a view of the constant
temperature room. To the right is an oxygen cylinder and at the top
of the picture is a manifold with tubing leading down to each of the
barrels.
A test, using three concentrations of residuals, was again conducted.
Oxygen was bubbled into the tanks at a rate prescribed by Standard
Methods. This method did not maintain sufficient dissolved oxygen
in the water, and the test was terminated after 24 hours.
It was then decided to use fritted glass diffusers to break up the oxygen
bubbles into very fine bubbles. By this time, shiner perch were no
longer available as the test species. Permission was granted to use
stickleback in the bioassay.
Table 14 lists the conditions, variables and results for the bioassay
using oxygen and fritted glass diffusers.
After the 60-hour samples had been collected, the water from barrel
No. 4 was transferred to another barrel to facilitate a fish count. It
was possible to see the surviving fish in the other tanks. At the end
of 96 hours, the water was drained from each of the barrels to con-
firm the number of survivors. All test tanks had 100% survival.
As shown by the results, there was no pH problem nor dissolved
oxygen problem. The use of fritted glass diffusers greatly enhanced
the dissolution of gaseous oxygen into the water. During most of the
test, super saturation values of D.O. were recorded. The oxygen
flow to the tanks was periodically adjusted manually by reducing or
increasing the gas flow. The control tank did not show high D. O.
levels since oxygen was simply bubbled directly into the water rather
than being passed through a diffuser.
In the earlier bioassays, more than the actual ratio of solids to water
was used. Because of a calculation error, approximately twice the
amount of solids was used than the final calculation called for. In
other words, some bioassays were performed with ratios 2, 6, and
20, rather than 1, 3, and 10. Even under these more severe conditions,
fish survival was possible. Figure 21 photographically illustrates the
appearance of the three calculated ratios of waste solids to water.
266
-------
Figure 20. Constant Temperature Bioassay Room
267
-------
Table 14. Fish Bioassay No. 4 October 11-15, 1971
Conditions
1.
2.
3.
4.
5.
6.
Variables
Test fish - stickleback, 10 per barrel.
Water - sea water from Steinhart Aquarium, 40 gallons
each barrel.
Test container - 55 gallon steel drum with two poly-
ethylene liners.
Temperature - constant 15°C.
Waste - ground peach-pear solids.
Filter - pump inlet enclosed inside plastic tray.
Cheesecloth wrapped around outside of plastic tray.
1. Barrel No. 1
2. Barrel No. 2
3. Barrel No. 3
4. Barrel No. 4
control
0. 35 Ibs waste
1. 05 Ibs waste
3. 50 Ibs waste
Results
Period: 0 hrs
Sample pH
D.O.*
control
Ix
3x
lOx
7.6
7.8
7.8
7.8
7.7
7.6
7.7
7.5
Period: 12 hrs
Sample
control
Ix
3x
lOx
pH
7.4
7.3
7.0
6.9
D. O. S.S. * * Turbidity
11.1
34.5
27.0
34.3
* D. O. = Dissolved oxygen, ppm
**S.S. = Suspended solids, ppm
*** Turbidity = JC units
268
*»"• *»•• 'r*
26
29
35
65
< 25
< 25
25
71
-------
Table 14. Fish Bioassay No. 4 (continued)
C. Results (continued)
Period: 24 hrs
Sample
control
Ix
3x
lOx
Period: 36 hrs
Sample
control
Ix
3x
lOx
Period: 48 hrs
Sample
control
Ix
3x
lOx
Period: 60 hrs
Sample
control
Ix
3x
lOx
pH
7.4
7.2
6.9
6.5
ElL.
7.4
7.2
7.0
6.4
PH
7.6
7.5
7.5
6.6
pH_
7.2
7.2
7.1
6.6
D.O.
9.0
24.0
18.8
28.4
D.O.
8.5
24.7
20.0
17.5
D.O.
8.6
27.0
25.0
11.0
D.O.
11.4
9.9
33.5
32. 1
S.S.
15
24
35
50
S.S.
12
28
32
54
S.S.
^^^^^••M
' 5
47
31
52
S.S.
0
30
36
55
Turbidity
< 25
< 25
< 25
59
Turbidity
< 25
< 25
< 25
53
Turbidity
< 25
< 25
< 25
46
Turbidity
< 25
< 25
< 25
40
269
-------
Table 14. Fish Bioassay No. 4 (continued)
C. Results (continued)
Period: 72 hrs
Sample pH D. O. S. S
Turbidity
control
Ix
3x
lOx
7.2
7.1
6.9
6.2
8.0
27.6
19.4
13.8
44
62
55
64
< 25
< 25
< 25
37
Period: 84 hrs
Sample pH
Period: 96 hrs
Sample pH
D.O.
D.O.
S.S.
S.S.
Turbidity
control
Ix
3x
lOx
7.5
7.4
7.4
6.9
11.3
27.5
19.9
21.1
51
40
60
78
< 25
< 25
< 25
< 25
Turbidity
control
Ix
3x
lOx
7.1
7. 1
7.1
6.8
10. 1
23.2
16.4
18.2
49
41
60
76
< 25
< 25
< 25
< 25
It is believed that all data in this report, the characterization of the solids,
the monitoring trips, and the bioassay provide the necessary information
to state that food processing solid residuals are non-toxic and can be
discharged into the marine environment without detrimental effects to the
quality of the receiving water or the marine life. .
270
-------
3X
IQX
RATIO OF SOLIDS TO WATER
Figure 21. View of Three Ratios of Solids
:er
-------
ALTERNATE METHODS OF DISPOSAL
According to a recently completed survey (in publication) the food pro-
cessing industry annually generates over 9 million tons of food residuals
during the canning, freezing and dehydrating of fruits, vegetables and
seafoods. Of the total quantity of food residuals, approximately 75% is
utilized for by-products, primarily as animal feed; about 20% of these
materials are disposed of as solid waste; largely through land disposal
methods; some 3% is disposed of in a liquid medium, most frequently
with processing wastewaters. The method which is utilized for disposal
of residuals from any processing plant is dictated by numerous factors,
as discussed below.
About 5. 6 of the 7.1 million tons of residuals which are used as feed are
from only three products: citrus, corn, and white potatoes. These are
all large crops, producing large percentages of residuals, and generally
processed in regions where there are livestock to consumer the residuals.
Citrus and potatoes are processed the year around and corn residuals are
converted to ensilage which can be stored; these by-products are, there-
fore, available as dependable sources of feed materials. Thus, the two
limiting factors which determine the practicality of utilizing food residuals
for animal feed are proximity to livestock-raising areas and dependability
of supply.
Of the approximately 1.7 million tons of residuals which are handled as
solid waste, equal quantities are disposed of by landfill and spreading
techniques. Minor quantities of dry residuals are incinerated. However,
land disposal methods require adequate areas of land which are suitably
isolated from residental areas. Fill methods, whether as sanitary land-
fills or by cut-and-fill techniques, must be employed with careful consid-
eration of potential groundwater, as well as surface water, contamination.
In both cases, land used for disposal purposes generally has limited utility
for extended periods after cessation of disposal operations. Although
spreading, with subsequent discing, of agricultural residues and food
processing residuals is a common practice in rural areas, the space
requirements for this method of disposal are generally excessive.
By far the largest portion of the 0. 3 million tons of food processing
residuals which are disposed of directly into receiving waters is from
seafood processing operations. Fish and shellfish residuals are fre-
quently returned to the marine environment where these materials re-
enter the natural food-chain. Additionally, food residual solids are in
272
-------
some inland situations discharged.into lagoons, industrial treatment
systems, municipal sewage treatment plants and, in minor quantities
and very few instances, directly into receiving streams. However, the
frequency with which solids are discharged with processing wastewaters
is rapidly diminishing, due primarily to the increased difficulty of
treating such industrial wastewater to the degrees necessary to comply
with increasingly stringent discharge requirements.
To bring this discussion to a regional basis and closer to the case in point,
attention can be limited to two major fruit commodities -- peaches and
pears. In California a total of 245, 000 tons of peach residuals (84% of
the national total) are annually generated. Of the combined total, 330,000
tons, about 107, 000 tons are disposed of by fill methods, about 77, 000
tons by spreading techniques, some 23,000 tons in water -- namely,
ocean discharge, and 69, 000 tons as animal feed. The remainder is
utilized for various by-products, such as charcoal manufacture and
alcohol production. However, a recently implemented program of spread
and discing will shift a significant quantity from the fill-disposal residual
total to the spreading method.
Regarding alternate methods of disposal available to the food processors
located in the East-Bay, the choices appear all to few. By-product con-
version is, of course, the most desirable avenue. However, serious
limitations are imposed by current state-of-the-arts and economic factors.
Charcoal manufacture is limited to utilization of peach pits; all recoverable
pits are now so being utilized. Alcohol production is limited by the
seasonality of the fruit operations and the handling capabilities of local
wineries. Animal feed is rendered impractical by the seasonality and
the distance to livestock-raising areas.
Although sanitary landfill sites are used extensively for the disposal of
domestic refuse and most industrial wastes, the number of such sites
in the East Bay are limited; many are rapidly being filled to capacity.
For the most part, these sites are located directly adjacent to San
Francisco Bay and are therefore subject to salt water infiltration and
subsequent dangers of water pollution. The high moisture content of
fruit residuals enhances the potential occurence of leachate, thereby
further limiting the use of available landfill sites.
Spread and discing disposal operations appear to be the most promising
alternative method. However, large acreage must be available to properly
conduct such Derations in a manner which will prevent or minimize the
occurrence of environmental problems. Urban expansion in the East
Bay has been proceeding at an accelerated rate during the past several
years. This urbanization process has made unavailable the required
273
-------
acreage with sufficient isolation to permit land disposal operations
within relatively close proximity to the food processing plant. There-
fore, although a spread and discing operation is a feasible alternative,
the implementation of such an operation can be realized only through
a considerable capital outlay and increased transporation costs due
to significantly longer hauling distances. Furthermore, there can be
no assurances that urban encroachment will not quickly render such
an operation impossible.
274
-------
ACKNOWLEDGEMENT
Advisory Committee
Mr. Robert E. Hillman
Mr. Nick Pateman
Mr. Herbert E. Stone
Mr. Jack Liebig
Mr. Lou Schmitz
Mr. Lawrence K. Taber
Dr. Teng-chung Wu
Mr. Richard Wood
Mr. John Ladd
Mr. Allen M. Katsuyama
Mr. Richard W. Sternberg
Mr. Walter A. Mercer
Mr. Walter W. Rose
Hunt-Wesson Foods
Hunt-Wesson Foods
Del Monte Corporation
Stokely-Van Camp
Oakland Scavenger Co.
Canners League of California
California Regional Water Quality
Control Board - S. F. Bay Region
California Regional Water Quality
Control Board - S. F. Bay Region
California Dept. of Fish and Game
National Canners Association
National Canners Association
National Canners Association
National Canners Association
Listed above are the names and affiliations of committee members and
others who provided valuable assistance and guidance throughout this
study. Without their help the task of carrying out the program would
have been most difficult.
275
-------
PROCESS DESIGN FOR TREATMENT
OF CORN WET MILLING WASTES
by
H. 0. Sensing* and D. R. Brown**
INTRODUCTION
Starch has been manufactured from corn commercially for more than
100 years. In the early days of the industry, only starch was
recovered; all the other components of the kernel were discarded.
Toward the end of the 19th century the corn millers began to
realize that the non-starch fraction of corn had value as an
animal feed.'l) Later, a process for separating germ and recovering
the corn oil was developed. Improved methods for steeping the
corn permitted evaporation of the steepwater, and recovery of
the solubles as part of the animal feed. By the beginning of
the 20th century, practically all of the corn kernel was being
recovered, including a large fraction of the solubles.
There remained, however, one large source of liquid waste. Water
used for washing solubles from the starch was sewered. These
solubles, amounting to about 2% of the corn, must be removed to
obtain the best quality starch and syrup products.
CLOSING THE LOOP
For many years this wash water stream was considered too dilute
to recover. However, a study was started in 1920 at the Argo
plant of Corn Products Refining Company (now CPC International,
Inc.), in cooperation with the Chicago Sanitary District, which
resulted in a process in which the wash waters were used for
steeping the corn.'2, 3) The resulting "bottled up" wet milling
process (Figure 1) is now standard throughout the industry.
Corn is steeped by soaking in process waters. The resulting
water is evaporated to concentrate the solubles, and can be used
as an additive to the animal feed products, or sold separately
as a liquid cattle feed or a nutrient for antibiotic fermentations.
*CPC International, Inc., Industrial Division, Pekin, Illinois.
**CPC International, Inc., Industrial Division, Moffett Technical
Center, Argo, Illinois
277
-------
Corn
Steeping
Milling
Germ Separation
i 1
Fresh Water
V
Starch
Drying
Milling
Fiber
Washing
Starch-Gluten
Separati on
Modified
Starch
Evaporation
Steepwater
Oil
Extraction
Corn Oil
Corn Gluten Feed
High Protein
Gluten Meal
Corn Sugar
and Syrups
Figure 1. Corn Wet Milling Process
278
-------
After steeping, the corn is mildly milled, to break open the kernel,
and release the germ with as little damage as possible. The germ
is separated from the other components of the kernel with hydroclones,
and then dried and processed to extract the corn oil. The oil free
germ is added to the animal feed.
After separating the germ, the remainder of the starch and gluten
is released from the hulls. The free starch and gluten are separated
from the hulls by countercurrent washing and screening. The hulls
are dried, and combined with the concentrated steepwater and the oil free
germ from previous steps to make corn gluten feed.
The mixture of starch and protein that were separated from the hulls
are processed through centrifuges and a series of small diameter
hydroclones. This results in separation of the starch and protein,
as well as removal of solubles from the starch.
The protein fraction, referred to as corn gluten, is concentrated,
filtered, and dried. The product is principally used as a high
protein additive to feeds for broilers.
Fresh water is added to the hydroclone station, at the rate of about 12 to
15 gallons per bushel of corn processed. A significant portion of
this water consists of condensates recovered during evaporation of
finished products.
The finished starch product, still in slurry form, may be dried
directly as an unmodified starch, or treated by various chemicals
to make modified starch. Part of the starch stream is hydrolyzed
with acid, enzymes, or a combination of acid and enzymes to produce
corn syrup or dextrose.
WASTE SOURCES
The process shown in Figure 1 is usually referred to as the wet
starch process. The only waterborne waste from the wet starch
process is the condensate resulting from the evaporation of
steepwater. The condensate contains volatiles which are formed
during the steeping process, and are vaporized during evaporation.
The sources of other liquid wastes vary within the wet milling
industry, depending on the products made and the processes used.
Typically, in addition to the volatiles, the waste stream might
contain filtrates from the preparation of modified starches,
with dissolved chemicals used for modification, and some
soluble carbohydrate formed during the process. Another source
of waste is the impurities removed during the refining of corn
syrups and dextrose.
279
-------
These volatiles and carbohydrates exert an oxygen demand when
discharged to a stream or to a municipal treatment plant. This
has been recognized for many years, and various treatment methods
have been developed by members of the wet milling industry.(4» 5, 6)
WASTE CONTROL
CPC International operates four wet milling plants in the United
States. Two of these pay for treatment of their wastes in municipal
treatment plants. In the past, the other two discharged waste
directly to waterways. As awareness of the environmental effects
of direct discharge increased, it became evident that this practice
could not continue.
A consulting engineering company was retained to make a waste survey
at one of our plants, in order to determine the requirements to
meet existing effluent standards. The consultants prepared a
preliminary biological treatment design, based on their experience
with industrial wastes, and the results of the survey.
CPC International management was concerned about the risk involved
in installing a treatment process with no experimental data to
support the design. It was felt that maximum treatment efficiency
would result if specific treatment data were obtained for the
waste stream.
The waste summary also indicated that manufacturing process improve-
ments might significantly reduce the waste load to be treated.
Therefore, it was decided to study the treatability of the waste
stream, and at the same time to conduct a vigorous waste load
reduction program. The waste load reduction was an important
and integral part of the over-all pollution abatement program.
BOD of the waste stream was reduced to about one-half of its
original value by isolating sanitary wastes and sending them to
the municipal treatment plant; by installation of new process
control instruments 1n critical areas; by operator and supervisor
training regarding process losses, supported by an extensive waste
stream monitoring system; and by abandoning an intermittently
operated process which generated a significant waste load.
TREATABILITY STUDIES
It was expected that the carbohydrates and volatiles in the waste
stream would be readily biodegradable. Therefore, the experimental
program was limited to study of the biological treatment process.
The biological process utilizes a mixed bacterial culture in
contact with the waste stream, to convert soluble organics to
insoluble bacterial cells.
280
-------
Numerous variations of the biological process have been developed.
Our consultant recommended that the experimental program be
limited to evaluation of aerobic processes.
The experimental work was conducted under the guidance first of
A. W. Busch (then at Rice University), and later W. B. Davis
(formerly at Texas ASM University).
It was decided to study two variations of the aerobic biological
process. One was an aerated lagoon and settling process, which
is simply a lagoon where oxygen is supplied to the mixture of
waste and culture, followed by a quiescent pond where the biomass
is allowed to settle. No biomass is recycled to the aeration
tank. This method of treatment has been used by one wet milling
company, and was described by Mclntosh and McGeorge.(6) This
process requires very little operator attention, but has the
disadvantage that there are no operating controls to compensate
for variations in waste characteristics or concentration. A
large land area is also required.
The other system studied was the completely mixed activated sludge
process. This consists of an aeration tank, usually followed
by a gravity clarifier. Biomass concentration in the aeration
tank can be controlled by recycling clarifier underflow. The
advantage of this method of treatment is that operating conditions
can be controlled by adjusting the biomass recycle rate.
EXPERIMENTAL RESULTS - AERATED LAGOON
The aerated lagoon process was studied on a pilot plant scale.
The aeration tank volume was 35,000 gallons, equipped with a
5-hp surface aerator. The settling pond was about the same size.
It was found that a satisfactory effluent could be obtained at
retention times as low as 4 days. Satisfactory biomass separation
was obtained in the settling pond, although occasionally in warm
weather clumps of sludge floated to the surface.
Projections of the size of the full scale treatment process showed
that sufficient land was not available at the plant site. Since
no land was available adjacent to the plant site, an expensive
pumping and piping system would have been required. As a result,
it was decided that the activated sludge process would be the
most economical for this location.
281
-------
EXPERIMENTAL RESULTS - ACTIVATED SLUDGE
Activated sludge treatment was evaluated on a laboratory scale
using techniques described by A. W. Busch.C?) The equipment is
diagrammed in Figure 2. The laboratory reactor studies were
designed to develop a culture acclimated to the waste under
continuous flow conditions. After several weeks of continuous
operation at the selected conditions, the capacity of the culture
for removal of soluble COD from tfye.waste was determined by a
batch test as described by Bused.v/J
The batch test consists of aerating a mixture of waste and
acclimated culture. Samples are taken frequently during the
test, and analyzed for soluble COD and suspended solids. The
results are plotted as shown in Figure 3. The slope of the COD
depletion curve, and corresponding values of suspended solids,
are used to prepare a unit rate of removal curve. An example
of a unit rate of removal curve is shown in Figure 4. This
curve shows the rate of COD removal that can be obtained for
any effluent COD. By selecting an MLSS concentration, the
aeration tank volume for the desired effluent COD can be calculated.
A series of these curves was obtained during the experimental
program, and the most conservative values were used for the final
design.
Biomass growth rate was estimated by material balance calculations
from operation of the continuous laboratory reactors. The growth
rate was correlated with food to mass ratio (F/M) as shown in
Figure 5.
Oxygen uptake rates were also determined from the continuous
reactors. The air supply was shut off, the oxygen depletion
measured, and correlated with F/M. These results are shown in
Figure 6.
The batch test results, together with the biomass growth rate
and oxygen uptake curves, were used to design the aeration tank
for the treatment plant.
TREATMENT FACILITIES
The flow diagram of the treatment plant that was designed from
the laboratory data is shown in Figure 7. Some of the waste
streams are discharged batchwise, so an equalization tank is
used to blend out variations in flow, concentration, and pH.
The equalization tank also provides some surge capacity for
accumulation of the waste in case of equipment failure, and as
a source of supply to maintain the culture during weekends, when
little waste is discharged from the manufacturing area.
282
-------
To
Aspirator
2 Liter
Percolator
6 Liter
Percolator
Timer
Effluent
Storage
Air Diffusers
Air
Rotameter
Solenoid
Valve
Pump
Substrate
Reservoir
Waste
Mixed
Liquor
Figure 2. Schematic Drawing of Laboratory
Activated Sludge Reactor
.283
-------
1200
1000
800
MLSS
ID
-------
CO
CO
5
a
o
CJ
<8
>
O
(U
or
a
o
o
at
S 3
o
CO
<*-
o
0)
4-»
(O
a:
J.
J.
JL
100 200 300 400
Residual Biodegradable COD, mg/1
500
Figure 4. Typical Unit Rate
of Removal Curve
285
-------
a
^>H
to
CO
c
o
-------
60
CO
o
X
l/l
o
-M
2
01
-Q
^"
CM
O
o
fO
N
0)
cn
40 *
20
Continuous Reactor Data
1 2
lb Soluble COD Supplied/lb MLSS/Day
Figure 6. Oxygen Utilization
287
-------
N>
00
00
Process
Waste
1
Equalization
Gravi ty
Clarifier
Cooling
Aeration
Aeration
Dissolved Air Flotation
Excess Biomass
Treated
Effluent
Figure 7. Treatment Plant Flow Diagram
-------
Flow from the equalization tank goes to two aeration tanks in
parallel. The raw waste temperature can get as high as 140°F,
so some or all of the aeration tank supply can be directed over
a cooling tower, to maintain the design temperature of 75°F in
the aeration tanks. Fixed mount surface aerators are used to
provide the oxygen.
Effluent from the aeration tanks is pumped to a circular gravity
clarifier. Recycle and excess biomass are pumped from the bottom
of the clarifier.
Overflow from the clarifier goes to a dissolved air flotation
cell, before discharge to the stream.
The treatment plant flow sheet is quite conventional. The difference
between this and many other installations is that the process was
designed for a specific waste, using relatively new laboratory methods
for obtaining the design data for a completely mixed activated sludge
process. In recognition of this, the U.S. Environmental Protection
agency awarded CPC International a construction and demonstration
grant. Certain eligible demonstration costs were funded to a maximum
of 7Q%, together with a fixed amount for construction, based on 10%
of the estimated constructi9n cost. The maximum award was equivalent to
about 27% of the total eligible estimated construction and demonstration
costs. In plant sewer changes, development work and biomass disposal
facilities were not part of eligible costs.
TREATMENT PLANT OPERATING RESULTS
The treatment plant has been in full operation for about 6 months.
The results have shown that the rate of soluble COD removal closely
matches that predicted by the laboratory tests. Oxygen uptake also
was closely predicted. Positive dissolved oxygen concentrations
are maintained up to the maximum design loading of the treatment
plant. Excess biomass production is also within the range predicted.
A major difference betv/cen laboratory and full scale performance
has been in the physical characteristics of the biomass. During
operation of the laboratory reactors, growth of filamentous organisms
was a frequent problem. It was because of this that the flotation
cell was included in the treatment. It had been found during the
laboratory studies that the filamentous growth could be separated
by dissolved air flotation.
In the full scale plant, filamentous growth has not occurred.
However, a continuing problem has been a dispersed growth, which
results in excessive suspended solids in the effluent. While
most of the biomass forms a floe with fairly good settling
characteristics, a fraction of the growth remains suspended as
individual bacteria. The particles are too small to be removed
in the dissolved air flotation cell without the use of a chemical
flocculating agent.
289
-------
The high suspended solids level in the treated effluent not only
results in failure to meet the suspended solids criteria, but also
causes a high BOD due to the oxygen demand of suspended bacteria.
There has been a continuing program to determine the cause of the
dispersed growth. Variables that have been or are being studied
include stability of waste load and pH, effect of F/M ratio, factors
affecting the growth of protozoa, which have generally been lacking
in this system, and the effect of ammonia nitrogen concentration.
The results of this work will be included in the project report
that will be prepared upon completion of the demonstration grant
program.
SUMMARY
During many years of development of the corn wet milling process,
product losses to liquid effluent streams were greatly reduced
by recycling process waters, and recovering solubles as a by-
product.
As the need for additional improvement in effluent quality became
known, product losses were further reduced by process modifications.
Laboratory treatability studies were used to determine the require-
ments for treatment of the remaining waste by the completely mixed
activated sludge process. Good agreement was obtained between
laboratory and full scale operation with respect to rate of soluble
COD removal, oxygen requirements, and biomass growth rate. Physical
characteristics of the biomass differed between the laboratory and
full scale processes. Filamentous growth was a major problem in
the laboratory, while dispersed individual bacteria has been a
continuing problem in the full scale plant. This has resulted in
failure to meet the design effluent suspended solids and BOD
concentrations. A program to determine the cause of this problem
is still in progress.
290
-------
REFERENCES
(1) Jeffries, F. L., Corn Grinding as I have Seen It. Corn Products
Company.
(2) Mohlman, F. W. and A. J. Beck, Industrial and Engineering
Chemistry 21:205 (1929).
(3) Pulfrey, A. L., R. W. Kerr and H. R. Reintjes, Industrial
Engineering Chemistry 32:1483-1487 (1940).
(4) Van Patten, E. M. and Mclntosh, G. H., Industrial and Engineering
Chemistry 44:483-487 (1952).
(5) Hatfield, W. D., Industrial Wastes, Chapter 6, Corn Starch
Processes (W. Rudolfs, Editor), Rheinhold Publishing Company,
1953.
(6) Mclntosh, G. H. and G. G. McGeorge, Food Processing 25_, No. 1,
pp 82-86, January, 1964.
(7) Busch, A. W., Chemical Engineering 72_, 71-76, 83-86 (1965).
291
-------
SEPARATION, DEWATERING AND DISPOSAL OF
SUGARBEET TRANSPORT WATER SOLIDS***
by
I. V. Fordyce* and A. M. Cooley**
INTRODUCTION
Beet sugar factories are large users of water and the treatment
of this water before disposal as waste water is a problem which
affects the entire economics of sugar processing. It is necessary
then to develop methods which will permit satisfactory reuse of
the water with minimum amounts accumulated for treatment and
disposal to receiving streams.
The process stream accounting for the largest amount of both
water and solids is beet washing and transport water. This
stream is reported by Fischer and Hungerford (1) to contain the
dirt tare averaging 5 to 6% of the beet weight. The fluid ranged
from 1,2OO to 4,OOO gallons per ton of beets sliced with an
average of 2,34O for 58 factories included in their survey.
The transport water in most factories is recycled after separation
of much of the suspended solids. The water in the system at
Crookston, Minnesota was approximately 700,000 gallons and the
total circulated per day about 8 million gallons.
In the present study the wash stream was screened over .054 inch
,slotted vibrating screens and the settleable Solids separated in
a 115 ft. diameter by 8 ft. SWD clarifier. The overflow returned
directly to the beet flume and the underflow was pumped to mud
ponds for further settling and accumulation of solids. The pH
was adjusted to a high level in the flume water by the use of
slacked lime as a flocculating aid, and to minimize bacterial
growth.
* Research Chemist, American Crystal Sugar Company, East Grand
Forks, Minnesota
** Professor of Chemical Engineering, University of North Dakota,
Grand Forks, North Dakota
*** This investigation was supported in part by funds from the
Environmental Protection Agency, Water Quality Office, under
Grant No. 12060 ESC, and American Crystal Sugar C0mpany,
Denver, Colorado, and conducted at their Crookston, Minnesota
plant
293
-------
The underflow mud, in fluid condition, deposited in a settling
pond becomes septic as the organic matter is decomposed and
stabilized under the anaerobic conditions which exist, and odors
develop.
OBJECTIVES
The objectives of this study were:
A: Optimum clarifier operation when wash and flume water
were recycled,
B: Filtration characteristics of the underflow stream from
the clarifier.
C: Odor control in the filtered cake from the underflow
stream.
METHODS AND MATERIALS
Phase I of this project consisted in determining sizing and
operational parameters using an Enviroclear 3 ft. dia. pilot
model clarifier for additional thickening of the underflow from
the main clarifier and filtering the slurry in pilot model
filters. Three types of pilot model filters were tested: (a)-
continuous 3 ft. dia. x 1 ft, face Eimcobelt vacuum filter;
(b)- 3 ft. dia, x 1 ft. face Eimco precoat rotary vacuum filter
and (c)- an Industrial Filter and Pump Mfg. Co, pressure leaf
filter Model 112 BMD, Series R-8O. Filtration characteristics
were studied with a bench scale 1/1O sq. ft. test leaf vacuum
filter prior to pilot unit studies.
The data from Phase I were to be directed toward sizing and choice
of equipment for filtration of the complete underflow from the
clarifier and satisfactory disposal of the filter cake in Phase II.
The conventional mud settling ponds would not be needed if the
clarifier underflow were filtered and very little waste water
would have to be impounded with its odor problems and problems
of stabilization to an acceptable B.O.D. for discharge into a
receiving stream,
EXPERIMENTAL
Clarification
The treatment of flume water for clarification is complicated by
the fact that the volume rate of recycling varies with the addition
of condenser water to this stream. In addition the suspended
solids content depends upon soil conditions during harvesting of
the beets and while the beet tare, as stated earlier, averages
5 to 6 percent of the weight of the beet, it may range from less
than 3% to more than 10%. The pH of the flume water is controlled
by the use of lime but under certain conditions when the organic
content of the flume water builds up bacterial action may dominate
294
-------
and the flume water becomes acid with a slime forming growth.
Under these conditions paraformaldehyde or other bactericide may
be necessary for recovery of alkaline conditions with lime.
Temperature in the fluming system is usually a compromise between
that which does not permit rapid bacterial growth and that which
will allow handling and thawing of frozen beets.
The treatment of water to the clarifier in this study consisted
in control of pH with lime, and the addition of the waste lime
from the juice purification processing step. Some uncontrolled
variables complicated clarifier action and could not be predicted.
These consisted in accumulation of rather large amounts of beet
fragments when frozen beets were handled and possible defloccu-
lation of solids due to the inadvertant addition of phosphate
during boiler blow down.
The operation of the main clarifier in terms of quality of the
flow to the clarifier and the quantity of the overflow and under-
flow for a period of 36 days is given in Table 1.
The biochemical oxygen demand with some variations due to process-
ing of frozen beets reached a level and remained rather constant.
This has been the experience of others as reported by Blankenbach
and Willison (2).
The solids content of the underflow in most cases was too low for
satisfactory cake formation in a vacuum type filter and further
thickening was necessary.
The low solids content was not the result of lack of capacity of
the main clarifier but was a result of operation. Additional
water entered the system as condenser water and a like volume
had to be discharged from the cycle. This was discharged as
underflow from the thickener. Clarified overflow could have been
discharged and this would have resulted in a greater solids content
in the underflow. The location of valves at some distance from
the clarifier made it difficult to remove excess process water
except as underflow stream.
A comparison of settling rates of several polyelectrolytes was
made by jar studies at different polymer concentrations by
measurement of concentrated solids volume a* different time
intervals as shown in Table 2. The polyelectrolyte was added
to 500 ml. portions of transport water, stirred, and poured
into a 50O ml. graduated cylinder, and the volume of settled
solids was read at timed intervals. The clarity of the super-
natant was about equal for the different polyelectrolytes. Those
with the poorer settling rates had poorer clarity.
295
-------
Table 1.
Solids Concentrations in Main Clarifier
Feed to Clarifier
o>
4*
a
Q
Nov.
Nov.
Nov.
Nov.
Nov,
Nov.
Nov.
Nov.
Nov.
Nov.
Dec.
Dec.
Dec.
Dec.
Dec.
Dec.
Dec.
Dec.
Dec.
Dec.
Dec.
Dec.
Dec.
Dec.
Dec.
Dec.
Dec.
Dec.
Jan.
Jan.
Jan.
Jan.
Jan.
Jan.
Jan.
Jan.
15
16
17
18
22
23
24
25
29
30
1
2
6
7
8
9
13
14
15
16
20
21
22
23
27
28
29
30
3
4
5
6
1O
11
12
13
X
71
6.5
6.5
7.6
7.3
5.7
5.3
6.1
6.3
6.4
6.8
6.5
8.0
11.9
12.0
11.4
11.6
11.8
11.8
11.4
11.4
11.4
11.6
11.8
11.3
11.1
11.5
11.8
11.4
11.2
11.2
11.6
11.1
11.4
9.5
11.8
11.2
O
r-l
%
r-l\
0) O r-l
w cn e
27
33
2
11
30
60
38
17
30
75
15
33
15
16
17
15
10
30
20
17
20
21
16
10
12
10
4
5
17
8
10
12
3
10
15
•0
Q)
•o
C M
0) -O
O.-H
W r-l 6
SOP.
cn a
640
12O8
676
1416
1552
556
268
316
632
524
654
592
436
504
846
1124
474
688
168
668
512
508
488
696
1288
808
988
876
1368
1008
816
1132
1156
1360
1240
816
Q>
i-l
,0
fl)
h W
QJ -O
•P -rl
r-l r-l H
•H O O.
fc. y> a
131O6
12548
12584
12570
24340
3500
1728
3654
4540
964
4421
1976
3116
2989
1691
1684
2104
342O
1904
2263
2144
2852
1328
804
Q e
o a
02 a
9600
9600
1O500
11400
90OO
122OO
6500
8300
6900
5250
6200
9150
8100
9150
6310
690O
8550
Clarifier Clarifier
Overflow Underflow
•o
0)
-o
c to
a
416
544
228
540
596
480
3OO
168
244
2OO
184
342
240
366
556
332
472
496
616
404
522
408
576
460
552
584
472
652
688
832
668
616
584
436
Q 3
o a
CQ a
129OO
8500
750O
810O
9200
10900
7250
6900
6650
5850
5700
825O
6000
8850
7500
6600
87OO
•»->
c en
QJ -D
O -H
H r-l
Q) O
CU CO
8.2
10.5
9.0
8.5
11.4
15.8
11.0
10.9
14.0
8.0
5.5
6.0
7.0
3.8
6.8
6.7
4.0
6.O
5.1
7.5
4.2
6.O
8.O
5.5
4.8
3.2
5.8
4.6
5.2
4.5
296
-------
Table 2. Settling Rates of Polyelectrolytes
Settled Solids in ml./5OO ml.
Poly. Cone. .5 ppm (1) 1 ppm (2) 2 ppm (3)
Settling Time (Min.) 2 _5 10 2 _5 10 2 5 10
Nalco 674 70 50 45 55 45 40 110 7O 62
Nalco 7460 65 47 42 40 35 35 110 70 62
Nalco ID 16-71 150 47 42 4O 35 27 100 65 57
Betz 142O 62 45 4O 30 30 3O 75 55 5O
Zuclar 110 450 62 5O 60 45 42 9O 65 55
Nalco 6O7 490 70 60 325 70 55 475 12O 87
(1) 1.5% Solids at 8.7 pH
(2) 2.8% Solids at 9.9 pH
(3) 1.4% Solids at 9.9 pH
A comparison of solids concentration in the underflow and clarity
of the overflow in the Enviroclear pilot thickener was made for
three polyelectrolytes at two concentrations with results as shown
in Table 3. The feed to the Enviroclear for this comparison was
screened transport water with main clarifier underflow makeup to
provide a uniform feed rate of 15 gal. per minute to the Enviro-
clear thickener at a pH of 11.4 without additional slacked lime
addition. The retention time in the Enviroclear was 10 minutes.
Table 3. Polyelectrolyte Comparison
Poly.
Betz 1420
Nalco 41AO6
Betz 1260
ppm
3
5
3
5
5
Underflow
Percent
Solids
18.2
29.0
16.6
20.2
15.8
Overflow
Sus. Solids
ppm
248
136
182
188
186
Lab. Test Leaf Filtration Studies
Laboratory filtration tests were done using a 1/1O square foot
filter leaf connected through a receiving flask to vacuum. The
vacuum could be adjusted to a maximum of about 20 inches of
mercury. The feed slurry, contained in a pail equipped with a
stirrer, was heated to the desired temperature and the leaf
inserted for two minutes of cake build up.
297
-------
The laboratory bench scale tests were done early in the season
before any bacterial growth appeared. The tests reflect character-
istics of a suspended solids content uncomplicated by bacterial
slimes. The pH could be controlled with reasonable amounts of
lime and flocculation could be achieved at the controlled pH with
reasonable amounts of polyelectrolytes. The physical character-
istics of the underflow from the clarifier determined that the
solids content was very critical in filter cake formation and that
rapid settling of part of the inorganic solids left a liquid sus-
pension which would not form a satisfactory cake*
A sample of slurry from the underflow of the large clarifier was
wet screened and the minus 20O mesh material was sized by ASTM
hydrometer method 422 (3).
The fractions above 2OO mesh were collected, dried and weighed.
The material above 48 mesh was mostly beet fragments and while
this was only about 3.2% of the total weight of solids, its bulk
was very high in proportion to the high density inorganic solids.
Screen analysis of the plus 2OO mesh fraction is shown in Table 4.
Table 4. Screen Analysis of Underflow Mud from Clarifier Collected
January 25, 1972
Tyler Mesh Percent
+20
-20 +35
-35 +48
-48 +65
-65 +1OO
-100 +150
-150 +200
-200
1.9
.4
.9
.6
1.5
1.3
2.6
90.8
Table 5 shows the size distribution of the minus 200 mesh mud.
Table 5. Size Distribution of -2OO Mesh Fraction by Hydrometer
ASTM Test Method 422
Size Microns Percent
Less than 1 2O
1-2.5 3.5
2.5-3 1
3-5 5.5
5-10 15
10-2O 16
20-30 10
30-74 29
298
-------
The hydrometer test was done after deflocculating the mud with
hexamet aphosphat e.
A sample with no deflocculant settled to a relatively clear top
liquid within 30 minutes but after addition of the deflocculant
there was no clear top fluid after 24 hours. The particle size
analysis shows the ultimate particle size but not the flocculated
aggregate in the feed to the filter.
In order to build up the solids content of the slurry feed to the
filter, dry lime cake from refuse disposal piles was reconstituted
and was used as a means of slowing the settling rate of the sand
fractions and as a filter aid. The effect of solids rate is
shown in Fig. 1. The solids added were of such fine particle
size that they aided filtration mainly by keeping the coarser
sand fractions in suspension and thus formed a more permeable
and firm cake. Pilot runs later with the belt filter gave good
filtration rates without the use of reconstituted lime mud if
the solids were concentrated properly in the thickener.
40
36
D 32
428
H
u.
.24
a
V)
.20
t/5
a
i
D
H
0
IT,
12
11.0 pH
90° C
15 in. Vac
10 15 20 25 30 35 40
PERCENT DRY SOLIDS
Fig. 1. Filtration Rate vs % Solids in Fjlter Feed
299
-------
The addition of slacked lime to control pH had a very great
effect on the rates of filtration. In this series of experiments
the alkaline underflow from the clarifier was brought down to
a pH of 5.5 by the addition of acetic acid and then adjusted to
increasing pH values by addition of calcium hydroxide. The amount
of calcium hydroxide necessary for pH adjustment was insufficient
to affect the solids content of the slurry appreciably. Increased
addition of lime as indicated by higher pH values increased the
filtration rate very markedly as shown in Fig. 2.
A reserve of calcium hydroxide as indicated by high pH was
necessary for good filtration. Slurries with pH near normal
were difficult to filter.
36
g32
"^28
H
U.
.24
a
^.20
V)
cc
1
in
0
W 8
^ 4
0
1
22.8% Solids
89° C
12 in. Vac.
••—
^
x^
X
i
X
/
r7
/*
5 6 7 8 9 10 11 12
pH
Fig. 2. Filtration Rate vs pH of Filter Feed
The effect of temperature on the rate of filtration at two pH
values are shown in Fig. 3 for a solids content feed of 25.85
and 34.5%. Increase in temperature resulted in an increased
rate of filtration and again the higher rate of filtration was
at the higher pH value.
300
-------
<
c.'
tn
36
32
28
24
20
5 16
i
en
12
8
a
D 4
0
• -
* -
i
34.5% Soli
25.8% Soli
X
1
4
rl
r-
^
X
X
0°
4°
ft
r
X
/
/
o
tr
ds
ds
X
/
/
X
84°
Ago°
/
• 4O°
8 9
PH
10 11 12
Fig. 3. Filtration Rate vs pH and Temp.
0
30 40 50 60 7O 80 90
TEMP. °C
Fig. 4. Effect of Heat and Polyelectrolyte on Filtration Rate
301
-------
Fig. 4 shows the effect of temperature and polyelectrolyte on
the rate of filtration at two pH values at a solids content of
2895 and 19,2% for the feed to the filter. The higher temperature
and pH values again improved the filtration rate. The pH adjust-
ment was made with calcium hydroxide and the increased filtration
rate may have been due to the effects of lime rather than pH as
such. The addition of 1 ppm anionic polyelectrolyte further
increased the filtration rate.
Table 6.
Data for Fig.
Filter Feed.
1. Filtration Rate vs Percent Solids in
(Increase in Solids Content from Dry
Waste Lime Solids)
pH
11.0
ll.O
11.0
11.0
11.0
11.0
ll.O
11.0
Feed
% Solids
15.0
17.3
19.5
21.5
23.5
23.5
23.5
23.5
Temp .
Deg. C
92
90
90
94
90
76
61
45
Vacuum
In. Hg.
15
15
15.5
16
16
15.5
15.5
15
Dry Cake
Lbs./Sq. Ft./Hr.
2.1
6.7
10.4
13.8
18.4
18.8
16.3
-------
Table 8. Data for Fig. 3. Filtration Rate vs pH and Temperature
ELL
6.6
6.6
10.9
7.2
7.2
11.0
11.0
Feed
% Solids
34.5
34.5
34.5
25.8
25.8
25.8
25.8
Temp.
Deg. C
24
80
84
34
90
90
40
Vacuum
In. Hg.
15
12
13
13
14.5
14
15
Dry Cake
Lbs./Sq. Ft./Hr.
9.8
18.2
30.9
3.2
5.2
23.8
13.7
Table 9. Data for Fig. 4. Effect of Heat and Polyelectrolyte
on Filtration Rate
pH.
10.5
10.5
10.5
9.5
9.5
9.5
Feed
% Solids
28.0
28.0
28.0
19.2
19.2
19.2
Temp.
Deg. C
35
90
90
32
90
90
Polyelect-
rolyte
ppro
0
0
1
0
0
1
Vacuum
In. Hg.
16
15
16
14.5
14.5
12.5
Dry Cake
Lbs./Sq. Ft./Hr.
9.5
14.4
2O. 7
1.6
7.7
9.9
Pilot Filtration
An Eimcobelt filter 3 feet in diameter by 1 foot wide was leased
and a series of 89 runs were made covering 18 days of plant
operation.
The feed to the filter came directly from the underflow of the
115 foot main clarifier with the provision also that this under-
flow could be thickened further in a pilot model Enviroclear
thickener. A heating tank was installed between the thickener
and the filter and chemical treatment or addition of filter aids
could be done in this heating tank, which was equipped with an
agitator.
To begin the study of the effects of certain variables on the
rate of filtration a number of conditions set definite limits
on many of the variables.
303
-------
In the recycling of transport water organic matter builds up to
levels favorable for bacterial growth. In order to keep bacterial
growth under control slacked lime was added to maintain high pH.
When the pH did lower unavoidably because of bacterial growth the
slime formation adversely affected the filtration rate. Other
variables interacted at times so that it was difficult to separate
cause from effect.
Easily filtered material also dried quickly in the dewatering
segment of the filter and cracked to such an extent that high
vacuum could not be maintained. The vacuum for best cake pickup
sometimes was at the lowest vacuum. The vacuum pump was a wet
type pump and the supply of water to the location housing the
filter was through a single pipeline. The supply could be either
hot or cold. It was found that hot water was desirable for
cleaning the filter belt after discharge of the cake but if
this water were used through the vacuum pump the vacuum was
several inches less than when cold water was used.
It would appear from the data presented and comparing leaf data
with rates of filtration on the belt filter that the leaf filter
was much more effective in terms of pounds of dry solids per
hour square foot. The data for the belt filter was calculated
on the basis of total drum area rather than area submerged and
consequently is about 1/3 less than it would be if calculated
on the basis of area forming cake. The rates of filtration in
the two types of equipment were roughly equivalent when calculated
on effective filter area*
Pilot filtration runs using the Eimcobelt filter were made on:
A^: Main clarifier underflow with pH adjustment followed by
additional thickening in the Enviroclear pilot thickener
and temperature adjustment of the final underflow.
B: Main clarifier underflow with pH adjustment followed by
additional thickening in the Enviroclear pilot thickener
and additional solids added as reconstituted waste lime.
C: Main clarifier underflow with pH adjustment followed by
additional thickening in the Enviroclear pilot thickener
and additional solids added as lignite fly ash.
D: Main clarifier underflow and additional thickening with
the addition of all of the lime cake from juice purifi-
cation to the main clarifier.
The addition of lime at the rate of O.31 Ibs. per 1O gallons of
underflow from the main clarifier to raise pH and additional
thickening in the Enviroclear pilot thickener before filtration
resulted in satisfactory cake pickup and cake separation from
the belt when filtered on the Eimcobelt filter. During the few
instances of poor cake pickup it was noticed that temperatures
304
-------
were down and also pH values had decreased. This latter effect
was due to a lack of sufficient lime and as in the filtration
with the leaf filter lime was observed to be beneficial in
filtering with the belt filter. Data for this series is shown
in Table 10.
Table 10. Filtration Rates for Vacuum Filtration
Feed
Temp. Percent Dry Cake
Run pH °C Solids Vac. Lbs./Sq. Ft./Hr.
Additions
5
6
7
8
9
10
11
12
13
14
18
19
20
21
22
23
24
25
26
27
28
29
30
12
12
12
12
10.9
10.9
10.9
10.9
10.9
10.9
12.1
12.1
12.1
12.1
12.1
11.8
11.3
11.3
9.9
9.9
9.9
11.8
11.6
82
60
62
78
90
80
70
57
65
60
85
7O
95
93
85
66
95
70
75
95
95
77
90
13.3
13.3
13.3
13.3
16.2
16.2
16.2
16.2
16.2
16.2
8.1
11.2
15.1
18.5
17.6
20.9
11
10
9
9
11
10
16
10
10
8
10
14
15
16
14
16
17
17
17
18
15
15
4.4
4.5
3.6
3.1
6.5
8.5
6.4
5.8
4.4
4.6
5.7
6.O
5.4
5.1
5.
3.6
7.2
3.5
2.8
3.7
5.3
7.1
11.4
None
it
ft
it
11
it
M
It
tt
tt
tt
tt
It
tl
tl
tt
tt
l»
tt
tt
tt
tt
It
The underflow from the main clarifier was run to the Enviroclear
thickener and then treated with additional lime solids from dry
waste lime cake reconstituted in the underflow to increase the
solids content. The pH was controlled by the addition of calcium
hydroxide. The cake pickup was variable but, except for the
beginning of a day's filtration, was very good. The additional
solids increased cake pickup. See Table 11.
305
-------
Table 11. Filtration Rates with Waste Lime Addition
Run
Feed
Temp. Percent Dry Cake
sH °C Solids Vac. Lbs./Sq. Ft./
Additions
31 10.9
32 10.1
33 11.2
34 11.2
35 12. O
36 12.0
37 12.1
38 12.1
38A 12.1
85
90
87
80
75
78
95
95
95
19.9
22.2
28.0
29.0
17.0
17.0
11.0
11.0
11.0
17
17
18
10
15
14?
14
9
39
39A
40
41
42
43
44
45
46
47
48
49
50
51
52
10.5
12.2
12.3
12.1
12.3
11.6
12.0
12.3
12.3
95
90
8O
85
95
80
90
90
9O
95
90
95
95
95
94
11.O
20.6
17.8
13.6
19.4
24.6
29.9
28
25.6
15
16
14
11
12
12
16
17
17
16
17%
17
16%
16%
15
4.1
3.9
6.3
5.1
11.6
6.4
3.5
7.4
6.7
2.3
4.1
11.2
10.8
9.2
10.5
3.4
4.3
8.8
5.1
4.7
7.8
10.1
9.1
9.6
W.L./40 Gal.
3O#
20#
10#
2O#
2O#
ti
it
it
tt
it
tt
tt
tt
it
it
tt
it
it
it
tt
tt
it
tt
it
tt
tt
it
ii
tt
it
it
ti
tt
it
tt
it
tt
tt
it
it
it
it
it
ti
it
tt
it
tt
tt
tt
tt
tt
it
it
tt
tt
tt
tt
tt
tt
it
W. L. = Dry Waste Lime Cake
The addition of fly ash after additional thickening of the main
clarifier underflow and adjustment of pH with lime was effective
as a filter aid although it was not significantly different than
equal amounts of reconstituted waste lime filter cake. See
Table 12.
The addition of all of the lime filter cake resulting from juice
purification to the clarifier and the adjustment of the pH with
calcium hydroxide and additional thickening in the Enviroclear
resulted in a filter feed which filtered at a higher rate than
any other combination. The solid cake was friable and non-
sticky and the pickup was much better than that when waste lime
or fly ash were used as filter aids. Decreasing the temperature
decreased cake pickup of run No. 72. When both the temperature
and pH were lowered the cake pickup was very poor. See Table 13.
306
-------
Table 12. Filtration Rates with Fly Ash Addition
Run
Feed
Temp. Percent Dry Cake
°C Solids Vac. Lbs./Sq. Ft.Air.
Additions
53
54
55
56
57
58
59
60
61
62
63
12.4
12.0
12.4
12.4
12.5
12.3
11.9
11.7
11.8
95
95
95
95
95
95
95
95
95
95
95
24.8
24.0
24.4
22.5
21.6
22.4
17.6
29.0
26.0
16
16
10
11
16
17
16
16%
14%
17%
16%
6
10
12
11
9
4
4
3
.0
.0
.6
.7
.1
.6
.3
.2
10# Fly
100
10#
5#
2.S#
None
None
10#
10#
10#
10#
tt
it
tt
»
it
tt
it
it
Ash/40
it
it
it
it
it
it
if
it
ti
it
ti
ti
ti
it
tt
it
Gal.
it
it
it
it
tt
it
it
it
Table 13. Filtration Rates with Waste Lime Filter Cake Feed to
Main Clarifier
Feed
Temp. Percent Dry Cake
Run pH °C Solids Vac. Lbs./Sq. Ft.Air.
Additions
68
69
70
70A
71
72
73
74
75
12,
12,
12,
12,
11,
7,
11,
11,
11,
.1
.0
.1
.1
,3
.0
.4
,5
»6
95
90
64
40
30
60
80
95
87
23,
19,
11,
11,
8,
.6
.8
.6
.6
,0
14
11
8%
10%
8
16
11
9
8
9
•
•
•
.
.
3
1
8
7
3
None Collected
26,
21,
15,
.O
.4
.8
14
14
16%
10
12
9
•
.
.
8
6
55
Lime Cake to Main
Clarifier
it
ti-
tt
11
it
it
11
it
Disposal 6f Filter Cake
Filter cake solids from the pilot filtration studies had moisture
content ranging from 39.0 to 50.0%. Three methods of disposal of
the filter cake solids are being studied. 1- Sanitary land fill
at three foot depth with one foot of earth cover; 2- Windrow
distribution on land by dump truck at approximately two foot depth
of pile; 3- Spreading on land by dump truck at approximately six
inch depth of solids. Decomposition studies will be continued
307
-------
after the spring thaw for decomposition rates and odor production.
Preliminary studies in 1971 and unpublished reports indicate that
odors from the above methods of solids disposal will be negligible,
SUMMARY
Vacuum filtration of thickened underflow from clarification of
beet wash and transport water was accomplished at reasonably high
rates by use of an Eimcobelt filter. The solids content of the
slurry was important and best results were obtained when solids
content in the feed were above 10%, and preferably over 2095,
Addition of calcium hydroxide to pH values of around 11 improved
filtration rates and at pH values near 7 there was very little
pickup of cake.
When bacterial growth takes place the slurry is very difficult to
filter. The recovery of an alkaline pH is difficult to achieve
with the use of lime alone but can be accomplished by the use of
paraformaldehyde in the transport water at a 0.0296 dosage. Lime
alone can be used in reasonable amounts for control of pH and
bacterial control after formaldehyde has been used as a bacteri-
cide.
Both lime cake and fly ash are effective filter aids.
Addition of lime filter cake from juice purification to the
clarifier gave an underflow which had the best filtration
characteristics of the combinations tried.
308
-------
LITERATURE CITED
(1) FISCHER, JAMES H. and HUNGERFORD, E. H. State of the Art
of Sugarbeet Processing Waste Treatment. Second National
Food Wastes Symposium Proceedings. National Sumposium on
Food Processing Wastes, P. 597, Denver, Colorado (1971).
(2) BLANKENBACH, W. W. and WILLISON, W. A. "Beet Sugar
Technology", 2nd Edition, McGinnis, P. 649 (1971).
(3) Standard Methods of Particle Size Analysis of Soils, ASTM
D422-63. "1971 Annual Book of ASTM Standards".
309
-------
WINERY WASTEWATER TREATMENT***
by
Edwin Haynes*, George Stevens*, and Paul Russell, Jr.**
INTRODUCTION
In 1969 experience with treatment of winery wastewaters in
this Country was limited to one winery utilizing aerated
lagoons. In California, where the soils and climate are suit-
able, irrigation and ponding of the wastewaters is used for
disposal. In the midwest and eastern areas of the United
States, where this technique is not feasible due to climato-
logical hinderances, other techniques must be employed.
j1
In 1969 Widmer's Wine Cellars, Inc. were faced with the
problem of providing a very high degree of treatment (96 to
99 percent BOD5 removal) of their wastewater. Research into
literature references failed to reveal any reliable experience
to draw upon. Data on treatment of similar industrial waste-
waters provided the only basis for planning and design of a
suitable Water Pollution Control Plant.
The preliminary proposal for this project included a long-
term activated sludge system followed by tertiary sand filter.
This system was designed to remove 981 of the BOD5 from the
winery wastewaters. This proposal was accepted by the Widmer's
Wine Cellars, Inc. and, with the assistance of a Demonstration
Grant from the Environmental Protection Agency, Widmer's
undertook construction of the proposed Water Pollution Control
Facilities. These facilities were placed in operation in
late 1970.
*Widmer's Wine Cellars, Inc, Naples, New York
**Harnish § Lookup, Associates, Newark, New York
***This project was supported by funds from the Environmental
Protection Agency, Project No. 12060 EUZ
311
-------
Widmer's Wine Cellars, Inc. is located in the Finger Lakes
Area of New York State. This area is characterized by steep
hills separated by five lakes, all located in a general north-
south axis as shown in Figure 1. The climate of this area
favors the growth of the characteristic hardy New York State
grapes, including principally Concord, Catawba, Niagara,
Delaware, Elvira, and Ives. It is said that the frequently
severe winters combine with the temperate summer weather to
give the New York State wines a very select characteristic
flavor.
GENERAL WASTE CHARACTERISTICS
During the fall months, beginning in the middle of September,
for a period of four to six weeks, the grapes are harvested
and brought to the winery from the vineyards in the valleys
and hillsides of the Finger Lakes Area. At the winery the
grapes are pressed into juice and stored for later fermenta-
tion. During the 1971 pressing season the winery wastewater
characteristics were as shown in Table 1 and Figures 2, 3,
and 4.
Table 1. 1971 Pressing Season Wastewater Characteristics
BOD5 Concentration* 1010 mg/1
BOD5 Discharge 1345 Ib/day
Suspended Solids 150 mg/1
Daily Flow 0.16 mgd
pH 7.4-7.9
Discharge* 10.6 pounds per ton
of grapes pressed
Daily Flow* 1420 gallons per ton
of grapes pressed
*90th Percentile Data
In the processing season, when grape juice is fermented into
wine and packaged for shipment, the wastewaters have somewhat
different characteristics and at Widmer's have been found to
be generally as shown in Table 2,
312
-------
/
•-J •-•
Horbof
/• S^M.Db
' • .Mum
r0He«iti,
! Xwolcc«e
Wtwl
_ .
Rochester
Sracuse
^^^^^^ [ K.OO o.r-o
MONROE . 0H,nrief)o4.E « (BP0|myrao Alron,
—tri Nework
o^"*" Moncheiler .
. Oc
roirmount
Pert Syron* njt«« ' "' ^ *
(Auburn
Trvman.burg *^, ol"1' ™« «d.ewo
^c^ o>->jra'nC
Hommond,pof» , ««*-B c»"- 4CHUYLEH
Xmu '. Wolkini GltnA
c' _ ,.
Atonlour Falltj, g0itsa
WIDMERS WINE CELLARS, INC.,
NAPLES , NEW YORK
FIGURE 1
NEW YORK STATE FINGER LAKES AREA
313
-------
100
90
•0
I
TO
3O
4O
$
20
200 400 SOO 800 WOO I2OO I4OO
BOD COMC.
Figure 2
BOD, CONCENTRATION
PRESSING SEASON WASTEWATER
Widmer's Wine Cellars, Inc.
314
-------
100
90
70
•O
3
5
90
10
400 (00 MO 000 000
•AJTHIHTEH - FLOW («AL/TO«)
WOO
MOO
Figure 3
WASTEWATER FLOW
PRESSING SEASON WASTEWATERS
Widmer's Wine Cellars, Inc.
315
-------
100 r
90
80
u
=5
y
o
sfi
w
>
fc
—
20 40 W M
POUNDS PtH TO*
00
110
120
Figure 4
BODr DISCHARGE
PRESSING SEASON WASTEWATER
Widmer's Wine Cellars, Inc
316 •
-------
Table 2, Processing Season Wastewater Characteristics
BOD5 Concentration*
BOD5 Discharge*
Daily Flow*
pH
*90th Percentile Data
1370 mg/1
0.57 pounds per case of wine
80,000 gallons per day
6.5 - 8.0
TREATMENT PLANT REQUIREMENTS
In New York State treatment requirements for any water pollu-
tion control plant are determined by the ability of the pro-
psoed receiving stream to assimilate the effluent discharge
to it without contravening standards established for that
stream. The streams in New York State have been classified
according to their "best usage".
The receiving stream at the Widmer Project is a tributary
to Naples Creek, which is well known in New York State as
one of the best fresh water trout streams in the area. Annu-
ally, in the spring, lake trout leave Canandaigua Lake and
migrate upstream to spawn. Oxygen levels in the stream must
be maintained at 4.0 mg/1 to support the trout fish life. The
tributary to the trout stream is a small intermittent stream
with no flow during the critical warm summer months. Conse-
quently, the effluent discharge to the tributary constitutes
the entire stream flow during these critical periods. The
operating permit conditions established by the New York State
Department of Environmental Conservation for the Widmer's
Water Pollution Control Plant are as shown in Table 3.
Table 3. Effluent Limitations Water Pollution Control Plant
Widmer's Wine Cellars, Inc.
Concentration 60 mg/1
Suspended Solids
Concentration 5 mg/1
317
-------
WATER POLLUTION CONTROL PROJECT
At Widmer's the Water Pollution Control Project included
construction of an Interceptor Sewer and a Water Pollution
Control Plant. The Interceptor Sewer was constructed parallel
to the drainage ditch to intercept all the existing wastewater
discharges. The Interceptor Sewer conveys the winery waste-
waters to the Water Pollution Control Plant located near the
processing plant. All domestic wastes at Widmer's are dis-
posed of utilizing septic tank and leach field facilities.
The Water Pollution Control Plant includes an entrance
structure, aeration units, final clarifiers, tertiary sand
filter, and an aerobic digester, as shown schematically on
Figure 5.
Entrance Structure
The entrance structure includes a parshall flume with a flow
meter recorder, a sludge transfer pump, and wastewater condi-
tioning facilities. The parshall flume and flow meter recorder
allow the operator to determine the pattern of wastewater
flow as well as the total flow into the plant. The sludge
transfer pump is a plunger type of pump used to transfer di-
gested sludge from the digester to a tank truck for disposal
in the vineyards.
The wastewater conditioning facilities include three chemical
feed pumps. pH control is accomplished using a pH probe which
monitors the pH of the wastewater leaving the entrance struc-
ture. The probe signals a controller which combines it with
the flow meter signal and automatically adjusts the feed rate
of the caustic soda. Caustic soda is metered into the waste-
water flow as required to maintain a pH of the raw wastewater
above 7.0. Nutrients required for the biological treatment
system are provided by the addition of ammonia water and
phosphoric acid. Chemical feed pumps are used to pump these
chemicals into the wastewater stream at a rate directly pro-
portional to the influent wastewater flow. A flow signal is
received from the recording flow meter and used to control
the proportion of the nutrient materials fed by the pump. By
manually adjusting the proportioner control, the flow signal
can be amplified or reduced to control the nutrient feed rate.
Aeration Units
There are four aeration units which can be operated in parallel
or in series at this plant. Aeration units 1 and 2 are 64 feet
in diameter with a 10 foot liquid depth, each providing a
volume of 120,000 gallons. Aeration units 3 and 4 are 76 feet
in diameter and 10 feet deep, each providing a total volume
of 192,000 gallons. All aeration units are constructed as
earthen lagoons and equipped with two-speed 10 hp mechanical
surface aerators. The detention time in the aeration units
can be varied from approximately two to eight days (at 0.12
mgd wastewater flow).
318
-------
Figure 5
WASTEWATER PROCESS FLOW SCHEMATIC
WATER POLLUTION CONTROL PLANT
Widmer's Wine Cellars, Inc.
319
-------
Clariflers
Clarification is accomplished using two 16 foot diameter units
with a 7 foot liquid depth. These units provide 2.81 hours
detention of the design average flow during pressing season
(0.12 mgd). Each clarifier is equipped with rapid sludge
removal equipment in an effort to minimize the detention time
of the sludge in the clarifier.
Tertiary Filter
The tertiary filter includes two sand beds, each with an area
of 67.5 square feet. Figure 6 shows a schematic diagram of
the tertiary sand filter. The sand filter beds are very
similar to rapid sand filters used in water treatment plants.
The filters are located in the Filter Building along with
sludge recycle pumps that are used to return the settled sludge
to the entrance structure where it combines with the influent
wastewater flow.
Aerobic Digester
The aerobic digester is 60 foot in diameter with a 10 foot
liquid depth constructed as an earthen pond. One two-speed
10 hp mechanical surface aerator is installed to provide the
required oxygen for the digestion process.
Laboratory
New Laboratory equipment has been purchased and a laboratory
constructed adjacent to the existing wine laboratory.
CONSTRUCTION COST
The cost for construction of the Water Pollution Control
Facilities is shown in Table 4.
Table 4. Construction Cost Water Pollution Control Facilities
Widmer's Wine Cellars, Inc.
Interceptor Sewer $ 33,400.00
Plant Equipment 94,247.00
General Plant Construction 280,139.66
Electrical Construction 38,115.22
Total Construction Cost $ 445,899.88
320
-------
TERTIARY SAND FILTER
Figure 6
TERTIARY SAND FILTER
Widmer's Wine Cellars, Inc
321
-------
PLANT PERFORMANCE
After placing the Plant in operation and stabilizing the
biological process, the data developed indicated performance
generally as anticipated. Table 5 shows 90th percentile data
on plant performance.
Table 5. Plant Performance Water Pollution'Control Plant
Widmer's Wine Cellars, Inc.
PRESSING SEASON
COD
BOD5
Suspended Solids
Influent
1320 mg/1
1010 mg/1
Effluent
100 mg/1
40 mg/1
25 mg/1
Removal
92.5%
96 %
PROCESSING SEASON
COD
BOD5
Suspended Solids
Influent
1730 mg/1
1370 mg/1
Effluent
60 mg/1
33 mg/1
28 mg/1
Removal
96%
98%
322
-------
Treatment of Cheese Processing Wastewaters
in Aerated Lagoons
William C. Boyle and Lawrence B. Polkowski
Polkowski, Boyle, and Associates
Madison, Wisconsin
INTRODUCTION
The evaluations and findings reported herein were supported by EPA
Project No. 12060 EKQ for post-construction studies over a 12-month
period to demonstrate and evaluate the use of aerated lagoons for the
treatment of cheese wastes. The authors of this report were not
engaged to design or size the system employed, select equipment utilized
nor were they consulted regarding the process flowsheet applicable to
this wastewater treatment scheme. The authors were retained to conduct
the post construction study, direct frequency of sampling, recommend
analyses to be performed, and evaluate and present findings of the
performance of the aerated lagoon systems for the wastes received at
the treatment site.
The principal objectives of this study were to demonstrate the performance
of a staged aerated lagoon treatment plant utilizing the Helixor*
type of submerged aeration system treating cheese processing wastes
over a 12 month period of operation. Part of the evaluation was
directed to the performance of the aeration equipment employed wherein
mixing effectiveness in terms of liquid velocities produced,
uniformity of dissolved oxygen levels and sludge accumulations could
be ascertained under the conditions of operation and geometric
configuration of the lagoons employed. In addition the oxygen transfer
efficiency of the aeration system employed was evaluated under field
conditions. A major part of this study was to determine the BOD
removal rate functions for each stage of aerated lagoon treatment
noting the influence of BOD loadings, temperature and seasonal
variations in loading and performance obtained for this type of
biological treatment. The theoretical and applied concepts of biological
treatment related to low-solids aerated lagoon systems were employed
to evaluate the treatment system. Lastly, the performance of this
type of treatment was evaluated in terms of costs associated with the
wastewater characterists and the pounds of cheese produced.
*subsurface aeration unit manufactured by Polcon Corporation,
Montreal, Canada
323
-------
EXPERIMENTAL SYSTEM
The wastewater treatment system consists of two equal volume aerated
lagoons with a staged flowsheet wherein the effluent from Lagoon No.l
is passed to Lagoon No. 2 before final discharge of the treated
effluent. The lagoons have earth embankments with side slopes of
3 horizontal to 1 vertical, a water depth of 12 feet at the lowest
central portion of the lagoon, and a length-width measurement of
155 feet by 123 feet at the water line for a volume of 955,000 gallons
each (Figure 1). The first lagoon is provided with thirteen 6 foot
long 18 inch diameter Helixors arranged in a pattern of 2 rows of
4 units equally spaced along the intersection of the flat bottom
and side slopes of the long dimension of the lagoon. Five additional
units were added to this lagoon between the 2 rows of four units
such that 4 of the five units were equally spaced in 2 rows between
the 1st and 2nd and 2nd and 3rd aeration units. The fifth additional
aerator was equally spaced between the third and fourth unit
of the initial eight unit arrangement (Figure 1). The second
lagoon is provided with three aeration units arranged in a triangular
pattern close to the inlet end of the lagoon in the lowest central
section of the lagoon. A separate blower building with two 240 cfm
Gardner Denver rotary blowers (one standby), Model 3CDL5, provided
the air supply to both lagoons. Usual operating conditions required
only one compressor to be operative and it was assumed that the
air flow was distributed between the two aerated ponds with 80%
of the air flow supplied to Lagoon No. 1 and the remainder to Lagoon
No. 2. The air flow regulation and distribution was effected by
the number and size of air orifices providing air directly to each
Helixor. The air header piping and valving was arranged to permit
the control of air to a pair of aeration units in most instances;
however, several aeration headers supplied air to a single unit.
The valving in the aeration headers were used only for fully open
or closed conditions wherein the inlet orifices controlled the
distribution of air flow.
The wastewater is conveyed to the treatment lagoons through about
3000 ft of 8 inch transite pipe, passes through a 4 inch inverted
siphon to a Snyder-Teague sampling station and thence is discharged
through a 4" cast iron pipe to a point of entry to Lagoon No. 1 at
approximately mid-depth. The effluent from Lagoon No. 1 passes
through a submerged 4 inch cast iron pipe to the secondary lagoon.
The water surface elevation in both lagoons is controlled by the
placement of 4 inch cast iron riser pipe with the inlet to this
pipe, or overflow from the lagoons, at a fixed elevation to maintain
the 12 foot water depth. The effluent from the secondary lagoon
passes through another Snyder-Teague sampling station.
324
-------
KENT CHEESE WASTEWATER LAGOONS
inverted
N5
INTERMITTENT STREAM
I55'x 123* x I21 depth
CI
• •
• •
Helixors
PRIMARY
4"CI
15 5'x 123'x 12'depth
Helixors
•
Sampling
Station 2
SECONDARY
| J Blower house
FIGURE i
-------
OPERATION
The treatment system handled the wastewater from a cheese making
industry specializing principally in products of Ricotta, Parmesan,
Romano, and Mozzarella cheese. The sources of wastewater were
primarily from rinses and washes associated with the storage of milk,
transmission lines, vats and pasteurizer with a limited amount of
wastes of domestic origin. The by-product whey was collected and
transported to another site for recovery and only whey wastes
associated with washing and rinsing were discharged to this treatment
system. The sources of wastewater treated by the aerated lagoon
system are shown in Figure 2. The quantity or quality of rinsewater
from each operation was not determined in this study, but rather
the collective properties of the total discharge to the lagoon
system were determined.
The sampling stations provided flow measurements and flow composited
samples for the raw waste water and treated effluents. Serious operating
difficulties resulted in the raw waste sampling station due to the
accumulation of cheese solids upstream from the flow measuring control
section. The accumulation of solids resulted in inaccurate flow
measurements. The control section was modified somewhat but proved
to present difficulties throughout the period of the study. In order
to obtain reliable measurements of flow, it was necessary to meter
water use at the cheese processing plant and to determine boiler
feedwater requirements and the extent of infiltration of the conveying
sewerage system for reliable flow information. All reported data
requiring flow input were corrected for the inaccuracy of this sampling
station. A sampling station was not provided between the primary and
secondary lagoons; thus, grab samples of the primary lagoon contents
were taken near the effluent discharge pipe. Because of the long
detention times experienced in each lagoon, 45-75 days, and the ability
to maintain a dispersed or mixed condition throughout the primary lagoon,
this procedure was deemed acceptable.
Certain measurements were made daily for operation of the treatment
works such as D.O., pH, alkalinity, settleable solids, temperature,
and flow quantity whereas more detailed analyses for evaluating the
performance of the treatment system were obtained for raw wastewater
influent, primary lagoon contents near effluent structure, and secondary
lagoon effluent on an eight day sampling frequency. This permitted
each day of the weekly operation to be sampled every 56 days throughout
the one year study commencing on January 14, 1971. A sampling schedule
is outlined in Table I. All the analyses indicated in Table I were
performed by Corning Laboratories, Inc., Cedar Falls, Iowa. The
lagoon system had been in operation approximately eight months prior
to initiating the sampling program; thus, the data presented does not
represent start-up conditions, but there are indications that the
performance did not reach steady state in all respects particularly
regarding seasonal variations.
326
-------
FIGURE 2
SOURCES OF CHEESE PLANT WASTE
Transport 81 Delivery
3 tanks, 2 0/R tankers
2"S.S. CIP Lines
Storage tanks
2-6,000 gal, I-10,000 gal
2MS.S. CIP Lines —
Pasteurizer-Clarifier pump
2"S.S. CIP Lines
Vats
5-12,000 gal, 3-6,000 gal R-W-R
R-W-R
R-W-R
R-W-R
R-W-R
R-W-R
•R-W-R
CHEESE
Ricotta, Romano
R-W-R—Parmesan,Mozzarella
R-W-R-Hoops - Press
R-W-R-Whey Collect Tanks
R-W-R-Cheese Drain Tables
R-W-R—Packaging Tables
R-W-R—Plant Floor
R-W-R—Cooler Floor
WHEY
2"S.S.CIPLines-RW-R
Separator H W
2"S.S.CIPLines-RW-R
Storage Tanks—HW
2"S5.ClPLines-R-W-R
0/R Tankers
Domestic Wastes
* R-W-R - Rinse, wash, rinse
HW- Hand wash
327
-------
TABLE I
SAMPLING SCHEDULE
Sampling Sampling Points
Frequency Parameter or Determination Raw Primary Secondary
8 days BOD 5 day 20°C Total x x x
8 days BOD 5 day 20*C Soluble* x x x
8 days Total Suspended Solids x x x
8 days Total Volatile Suspended Solids x x x
8 days Total Coliforms x x
8 days Fecal Coliforms x x
30 days Total Phosphorus x x
30 days Total Kjeldahl Nitrogen x x
30 days Nitrate Nitrogen x x
All Analyses performed according to Standard Methods
*Analysis performed on sample filtrates
Additional operating and performance evaluations were performed
during the experimental period including the following items,
1. D.O. measurements with respect to horizontal and vertical
control in the primary lagoon,
2. measurements of velocity in the horizontal plane at various
locations and depths within the primary lagoon,
3. measurement of oxygen uptake of the treatment lagoon contents,
4. determination of the oxygen transfer coefficients of a and 6
to enable the evaluation of the aeration system employed.
Various other operating conditions and observations were recorded on
a routine basis to assist in the overall evaluation of the performance
of this treatment system.
Special measurement techniques employed for the purpose of evaluating
the aeration system employed a grid established in the primary lagoon
above the water surface to provide a measuring base for horizontal
control. At the time oxygen transfer was evaluated, it was necessary
to have a measurcable D.O. in the lagoon and evidence that the D.O.
was maintained at a uniform or steady state condition. The oxygen
uptake or demand of the lagoon contents were determined by taking a
number of representative samples of the mixture under aeration and
placing them in bottles capable of excluding further oxygen transfer
from the atmosphere and wherein the decrease in D.O. concentration
was measured with respect to time with a Yellow Springs Instrument
D.O. probe. In order to evaluate the influence of photosynthetic
328
-------
plankton on the oxygen transfer in the lagoon, oxygen uptake measure-
ments were made both on rates observed under light and dark conditions.
There was no discernible difference in the rates observed which
indicated that oxygen transfer or supply from this source was
negligible during the test periods. The efficiency was determined
on the basis of line to water for the complete aeration system wherein
power input was metered in each instance for amperage and voltage
drawn. The results were presented in terms of pounds oxygen transferred
per kw-hr. Thus, the reported efficiency included oxygen transferred
from the atmosphere as well as oxygen transferred by virtue of the
aeration system employed.
The measurements were corrected to standard conditions of zero dissolved
oxygen and 20eC with corrections for a and 8. A representative
sample of the lagoon contents were tested in Madison laboratories in a
diffused air system to compare transfer rates for the waste mixture
and tap water for two replicate samples. The ot values were corrected
for the oxygen uptake rates in the mixture at this time. The value a
was obtained as an average of the ratio of the transfer rates in the
wastewater and tap. The value 3 was determined on the basis of the
highest D.O. obtained in waste for a given temperature, checked
by the Winkler D.O. method, against the D.O. at saturation for tap
water at the same temperature.
The velocity profiles in the aerated lagoon were made with the use of
a Gurley Current Meter which was fixed in the horizontal plane by
attachment to a vertical rod. The current meter was rotated in the
horizontal plane at a predetermined depth and the maximum velocity
and direction were noted to obtain a vectoral representation of the
water movement in the lagoon. The velocity was observed in four
directions parallel to the sides of the lagoon in the central portion
of the aerated lagoon where a single maximum velocity component was
not observed due to the highly undirected flow patterns evident within
the area bounded by the aeration devices. An attempt was made to
measure the vertical velocity component immediately above the discharge
of the aeration device but the variation in fluid density as a result
of high levels of air entrainment caused on the measurements to be
somewhat erratic. Measurements were made one foot below the surface,
mid-depth and one foot from the bottom.
329
-------
RESULTS AND DISCUSSION
Aerator Performance
The performance of the Polcon Corporation subsurface aerators (Helixors)
was evaluated over the one year period in the primary lagoon only.
As indicated earlier, the lagoon was sampled at a number of points on
a grid (Figure 3) at selected depths to determine the oxygen uptake
rates, dissolved oxygen concentration, and temperature. Tests were
repeated five times over the grant period in order to evaluate perform-
ance under different waste loading and environmental conditions.
Oxygen Uptake Rates - The average oxygen uptake rates recorded in the
primary lagoon over the one year study period are presented in Table II.
The values reported represent the average uptake measured at a number
of selected points within the lagoon. Normally, the uptake rates
measured on any given day were within 10 percent of each other. The
uptake rates reported were not converted to specific uptake rates
(mg Oj/gVSS/day) since the volatile solids fraction measured in this
lagoon was not well correlated with the active biomass during the
study period. Large amounts of suspended volatile matter associated
with the wastewater contributed significantly to the total volatile
fraction measured* The influence of algal cells on the oxygen uptake
rates in the primary lagoon were negligible as measured by both dark
and light bottle uptake rates.
Examination of the uptake rates presented in Table II suggest that the
primary lagoon was relatively active as compared with other aerated
lagoon systems. The analysis obtained in May, 1971, occurred during
the anaerobic period and indicates that the lagoon was extremely
active. As discussed later, this high rate of oxygen consumption was
believed to be due to the rapid solubilization of organic matter and
synthesized cells which had settled in the lagoon and had subsequently
been stored over the cold winter months.
Oxygen Transfer Capacity - The values of the oxygen transfer capacity
of the lagoon contents, as measured by the ratio of the oxygen transfer
coefficients in the waste to that in tap water, are reported in Table III
as Alpha. These values represent the average values obtained from
several points within the lagoon. Alpha appeared to fluctuate
seasonally being highest during the summer months. There was not
sufficient data to establish any reliable correlations between alpha
and lagoon BOD solids or temperature, but it is reasonable to assume
that changes in the metabolic activity within the lagoon would result
in changes in the oxygen transfer relationships.
330
-------
PRIMARY LAGOON GRID
EPA-KENT CHEESE CO.
KL.C
1
£
"«
<;
i
"u
i
•
~t
1
1
^
i
•>
>
i
1 /
— —
\
^
_ —
1
LAG
2
3
•— . — ^_
4
DON NO. 1
5
6
.
— — —
7
8
9
— -. —
__
10
il
12
•
,
13
14
15
3
-*- OUTLET
FIGURE 3
I-station numbers
-------
TABLE II
OXYGEN UPTAKE
PRIMARY LAGOON
DATE
11-20-70
5-23-71
7-21-71
8-21-71
10-7-71
TEMP.
°C
6.3
17.0
24.0
23.5
16.5
D.O.
UPTAKE RATE
mg/l/hr Ib/day
2.9
0.0
4.5
4.7
2.2
2.1
5.6
1.2
0.8
1.2
427
1165
250
167
250
332
-------
TABLE III
OXYGEN TRANSFER DATA
PRIMARY LAGOON
DATE
11-19-70
5-23-71
7-21-71
8-21-71
10-7-71
TEMP.
°C
6.3
17.0
24.0
23.5
16.5
D.O.
mg/1
2.9
0.0
4.5
4.7
2.2
a
0.75
0.88
0.90
0.94
0.70
B
0.96
0.96
0.98
0.98
0.98
STD. 1
Ib/kw-hr.
5.55
3.55
1.14
3.00
CRANSFl
lb/h]
4.14
2.65
0.85
2.25
Average (excluding 0.81 0.97 4.03 3.01
8-21-71)
1 - 20°C, D.O. = 0.0, Tap water
333
-------
The solubility of oxygen was only slightly affected by the wastewater
characteristics within the primary lagoon. Normally values of beta
in long detention-type processes such as the one studied here approach
1.0.
Aeration Efficiency - The aeration efficiency of the Polcon Corporation
Helixors are presented in Table III for the five test days. The
aeration efficiencies were computed by employing the measured oxygen
uptake rates, dissolved oxygen concentration, alpha, beta, and
temperature. The value of the aeration efficiency was corrected
to standard conditions of 20°C, tap water (alpha and beta equal 1.0),
and a dissolved oxygen concentration of 0.0 mg/1. A sample calculation
appears in the Appendix.
The overall aeration of efficiencies in the primary lagoon were estimated
by assuming that approximately 80% of the air provided by the blower was
directed to the primary lagoon, since 13 of the 16 helixors were
located in the primary lagoon. During the August 21, 1971, test, both
blowers were in operation resulting in a doubling of the power input
to the aerators. Yet the actual measureable oxygen transfer rate was
not appreciably higher than for other test periods. It has been well
documented in the literature that aeration efficiency decreases with
increased air flow rates and this analysis tends to verify that fact.
In addition, however, it was determined that, during the operation of
both compressors, the line pressures increased very significantly
requiring the bleeding of air from one of the headers. This was
practiced by the use of a "blow-off" or "by-pass" Helixor in the secondary
lagoon. Thus, the poor transfer rates for August were not included
in the overall average for aeration efficiency.
The measured transfer efficiencies of the Helixor units were within
the values normally expected for this type of unit but tended to be
on the low side of expected performance. Whether this was due to
undersizing of the air headers, the geometry of the Helixor-basin
configuration, or was, in fact, the actual field expectation for
these units has not been determined but it suggests that caution must
be exercised in sizing aerators for lagoon systems.
Oxygen Dispersion - An important function of aeration devices in
biological processes is the dispersion of oxygen throughout the basin
contents. Normally, rule of thumb criteria recommend that at least
334
-------
4 to 10 horsepower per million gallons (hp/MG) be supplied to insure
adequate oxygen dispersion. For the primary lagoon, 8.5 hp/MG were
provided during the single blower operation. The results of dissolved
oxygen analyses in the primary lagoon for the five field surveys are
presented in Table IV. Examination of this data indicates that oxygen
was well dispersed throughout the primary lagoon.
Mixing and Solids Suspension - The D.O. parameter would be indicative
of the dispersion which can be affected of substances in the dissolved
state such as soluble B.O.D. However, the distribution of particulate
matter such as biological floe would be a function of the velocity
distribution and the velocities necessary to keep the particulate
matter in suspension. Normally, in aeration tanks in wastewater
treatment, velocities along the bottoms of these units would range
from 1.0 to 2.0 fps depending upon the geometry of the aeration system
employed. Velocity measurements within the lagoon can serve only to
show flow regimes developed within the lagoon with the given aeration
equipment for the placement arrangements employed and the geometry of
the lagoon. Effectiveness of the system in terms of keeping particulate
solids in suspension can be evaluated in a qualitative way by determin-
ing the location and extent of solids deposition on bottom surfaces
of the lagoon.
The maximum velocities observed in primary lagoon at the various depths
are reported in Table V for one blower, 192 cfm, and two blowers, 384 cfm.
These airflow rates correspond to 2.3 cfm per lineal foot and 4.6 cfm
per lineal foot respectively along the longest bottom dimension of
the lagoon.
Because of the upward vertical velocity components in the immediate
vicinity of the inlet and outlet of the Helixors and the necessary
compensating downward movement of water between adjacent aeration
units, no definitive flow pattern is discernible. However, in zones
peripheral to the aeration section, where the bottom of the lagoon is
sloped to intersect the water surface, horizontal velocities were
measured near the water surface indicating a general circulation
pattern towards the periphery of the aerated lagoon with velocities
ranging from less than 0.1 to 0.8 fps. Likewise, to compensate for
the outward movement of water toward the periphery of the lagoon
near the surface, water movement must be in the opposite direction near
the bottom of the lagoon, the measurements and magnitude of which was
less discernible. Thus, a circulatory pattern of flow developed, in
the outer prism shaped sections similar to that which is depicted in
Figure 4.
335
-------
CO
ON
Date
TABLE IV
DISSOLVED OXYGEN CONCENTRATION
PRIMARY LAGOON
Station Number
567
10
11
12
13
15
11/19/70
5/14/71
7/21/71
8/26/71
10/7/71
2.7*
2.7
-
0.1
0.1
-
4.4
4.3
-
4.1
3.9
-
2.2
2.0
2.1
2.9
2.8
2.8
0.1
0.1
0.1
4.4
4.2
4.2
4.3
4.6
3.0
2.2
2.1
2.0
2.9
2.9
2.7
0
0
0
4.4
4.3
-
4.7
-
-
2.7
2.7
-
2.7
2.7
2.7
0
0
0
4.3
4.3
3.0
4.3
4.3
4.4
2.3
2.4
2.3
3.1
3.0
3,0
0.3
0.2
0.2
4.3
4.3
4.3
4.4
4.4
4.5
2.3
2.3
2.3
2.9
2.9
2.9
0.1
0.1
0
4.4
4.. 3
4.2
4.7
4.7
4.7
2.4
2.4
2.4
3.0
2.9
2.9
0
0
0
4.6
4.7
4.7
_
-
-
2.3
2.3
2.3
2.8
2.8
2.8
0.3
0.2
0.1
4.7
4.7
4.5
4.7
4.6
4.6
2.4
2.2
2.2
2.8
2.8
2.7
0.1
0.1
0
4.2
4.2
4.2
—
-
-
2.3
2.3
2.3
2.8
2.8
2.8
0.1
0.1
-
4.8
4.7
4.7
_
-
—
2.3
2.3
2.3
2.8
2.7
2.7
0.3
0.3
0.3
4.4
4.4
4.3
4.4
4.4
4.5
2.1
2.1
2.1
2.7
2.7
2.7
0
0
0
4.3
4.2
-
_
-.
—
2.3
2.3
2.3
2.8
2.7
2.6
0
0
0
4.9
4.8
—
4.4
4.4
—
2.4
2.3
2.3
2.7
2.7
2.7
0.1
0.1
0.1
4.7
4.7
—
4.5
4.5
4.5
3.0
2.6
2.5
2.6
2.5
—
0.1
0
0
4.4
4.4
—
4.5
-
—
-
-
-
*D.O. values in mg/1 at 1 ft, 3 ft, and 5 ft.
-------
TABLE V
VELOCITY DISTRIBUTIONS IN PRIMARY LAGOON
November 7, 1971
One Compressor
Two Compressors
Station
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
Surface
0.1
0.1-0.2
0.0-0.1
0.4
0.2-0.5
0.1
0.2
0.5-0.8
0.1
0.0
0.3
0.1
0.2
0.2
0.0
Mid Depth
0.0
0.0
0.0-0.1
0.1
0.2-0.3
0.0
0.0
0.2
0.0
0.2
0.2
0.0
0.0
0.1
0.0
Bottom
0.0
0.0
0.0
0.0
0.1
0.0
0.0
0.2
0.1
0.0
0.1
0.1
0.0
0.0
0.0
Surface
0.0-0.2
0.1-0.2
0.2-0.3
0.6-0.8
0.2-0.6
0.0-0.2
0.4-0.5
0.8
0.2
0.4-0.5
0.3
0.1
0.2
0.2
0.1
Mid Depth
0.0-0.2
0.0-0.1
0.2-0.3
0.3-0.4
0.2-0.3
0.0-0.2
0.0-0.2
0.2
0.1
0.0-0.1
0.2
0.1
0.0
0.0
0.0
Surface
0.0
0.1-0.2
0.0-0.1
0.1=0.2
0.0-0.2
0.0-0.1
0.0-0.1
0.2
0.1
0.0
0.1-0.2
0.0
0.0
0.1
0.0
All values of velocity in ft/sec.
337
-------
INLET
AERATED LAGOON NO. 1
• ^^
•
• O Q Q •
o o o o .
0 ° OUTLET
Q o 0 0 o Q 0-
0 0
o o o o
• Q Q Q •
WATER MOVEMENT PROFILE
^^J y y y V V >( ^^
\
K—
/
V
\
l\
\\
>«
V 0 AERATOR
/SOLIDS ACCUMULATION
/^ HEAVY -UP TO 2"
(^MODERATE 1-2"
(^) LIGHT < l"
ONO MEASUREABLE
ACCUMULATION
FIGURE 4
-------
Perhaps a more meaningful observation that was made to ascertain the
ability of the aeration system to keep solids in suspension was to
estimate the accumulation of solids on the lagoon bottom. Utilizing
a D.O. probe, an estimate of the sludge accumulation was made by
lowering the probe to an elevation where the D.O. decreased to zero
and noted, and to a point where the weighted unit would come to
rest, a point which was presumed to be at the bottom of the lagoon.
The results were plotted qualitatively by the graphical representations
for deposit as shown in Figure 7. It is noted that the greatest
accumulation reported on the date of test occurred in the non-aerated
zones of the lagoon corresponding to the tapered prism sections
representing sloped sections of the lagoon nearest the intersection
of the two adjacent sloped bottom sections. The least discernible
deposits of solids occurred in the central aeration zone which may be
due either to the higher levels of fluid turbulence to keep the solids
in suspension or due to the greater diffusion of oxygen in the
lighter accumulations of sludge at these points. For longer periods
of treatment plant operation, it is likely that greater accumulations
will occur. However, at the time the determinations were made, it
appeared that the accumulation of solids would not present a serious
problem for this system.
Lagoon Performance
The performance of the staged lagoon system was interpreted in terms
of several measured parameters: BODij (total and soluble), suspended
solids, nitrogen, phosphorus, coliforms (total and fectl). The
results reported herein are subdivided in accordance with these
parameters. The loading to the lagoon system is summarized for the
one year study in Figure 8. It is apparent from this figure that flow
and organic load to the lagoon is quite variable over the one year
period. Hourly flows over a 24 hour period are presented in Figure 9
for two days, January 24 and 25, 1972. Analysis of this data indicates
that the ratio of maximum to average flow for the day was 1.9. The
average flow rate over the 12 month study was 17,000 gallons per day
including Sundays.
The apparent cyclic variation in BOD and solids loading to the lagoons
(Figure 8) are due to the sampling schedule employed. Therefore, a
trend line was difficult to describe. Average BOD loading over the
12 month study was 270 Ib/day and suspended solids loading was 85 Ib/day.
An average of 13,000 Ib cheese were produced per day (excluding Sunday)
requiring approximately 1.5 gallons of water per Ib of cheese and
resulting in 24 Ibs of BOD and 7.6 Ib of suspended solids per 1000 Ib
of cheese produced.
Biochemical Oxygen Demand - The performance of the lagoon system in
removing biodegradable organic matter was measured by the five day
339
-------
CHEESE PROCESS WASTEWATER LAGOONS
EPA-KENT CHEESE CO.
JAN 1971 - 1972
Lb 20
CHEESE
PRODUCED )0
xlO"3
50
40
FLOW
gpd 30
V
x ICj*
20
10
500
BOD
Lb/doy 30°
too
TSS "°
Lb/doy ,00
n
.. •• . *'...,"'*...
„ ' .:• . •• • ....*"•.*'•. "**.•••, v '••.•*.• •"..• .-•. .".*••*."'•' **•/,•**.•%'*.'••*. "'"/."•'"'.•
INFLUENT CHARACTERISTICS
* *
™ *
*
• * • .
.
» * •
- .- . • . •..''•*".
• • •*• **...• •« • •"•
• **»• •**. .**s*>" .**** *
•'•-.^<. . *.' '. • ."^r^^^^l^^ .'.;- -..%•'•..
• ^T*t^ _! 1 O • V « .«• «• • _~V* ' i ' —?'««'** •' • iJ^ . * *
+ ' ' *' s ' • •*'..*.'.'•
M ** « *
00 0°
• o GO o _ ^ °
o o o ° o o
00 000 ftO °« °0
o ° o » a°<> ° "o^ o°
o ° o o
0 0
0 O
o
o
; °0o °o0° °° °°00 °° o oo°°o 0°0o0° OQO QO° o
I O i i i i i i i i lOlOl
FIGURE 5
-------
CHEESE PROCESS WASTEWATER FLOWS
EPA-KENT CHEESE CO.
JAN 1972
INFLUENT HOURLY FLOW
VARIATION
1/24/72
tnox hr _ , ftfi
. - l.oo
9 12 3
TIME OF DAY
FIGURE 6
341
MID
-------
BOD 20°C determination. Both total and filtered analyses were
performed in order to reflect the influence of the pond system on
actual biochemical stabilization as compared with physical separation
of particulate organic matter. No long-term ultimate BOD analyses
were performed nor were COD or Total Carbon Analyses; thus, the
interpretation of the data in terms of mass balances of oxygen demanding
materials through the system was limited.
Although the BOD load to the lagoons varied widely over the one year
period of study, the most apparent influence on lagoon performance
was temperature. In Figure 7, BOD load and temperature are plotted
along with the primary lagoon dissolved oxygen (D.O.) concentrations.
It is immediately apparent that D.O. rapidly disappeared in the spring
along with rising temperatures. In fact, D.O. disappeared on April 10
and did not reappear until July 19. During the remainder of July, six
of thirteen days the lagoon was devoid of oxygen. Also 11 of 31 days
in August, 15 of 30 days in September, 19 of 31 days in October,
6 of 30 days in November, and 2 of 31 days in December D.O. values
were less than 1.0 mg/1.
It might be assumed that this increased demand for oxygen during the
spring was due to the increased biological activities brought about
by the warmer temperatures. However, examination of the BOD load just
preceding this period would indicate that the demands measured during
this period could not be accounted for by the applied load.
For example, if one assumes that the ultimate oxygen demand is 1.47 times
the 5 day value (deoxygenation constant, k^ - O.I/day), the oxygen
demand for an annual average of 5 day BOD load of 270 Ib/day would be
397 Ib/day. The oxygen demand measured in May, during the oxygen
deficient period, was 1165 Ibs/day, 768 Ibs in excess of that predicted
above. Furthermore, if one computes the oxygen supplied during this
period based on a standard transfer rate of 4.0 Ibs Q£ per Kw hr.,
approximately 600 Ibs. of oxygen are transferred per day by this
system at 20°C and zero D.O.
Therefore, it is reasonable to assume that significant amounts of
biodegradable organics are being solubilized from the benthal deposits.
During the cold months, anaerobic decomposition of the settled organic
matter slows down resulting in accumulations of this material. As
the temperature increases, biological activity also increases and
solubilization of the benthal deposits begin to appreciably contribute
to the organic load of the lagoon. This solubilization increases to
a maximum value and then remains constant over the summer months. It
may be assumed that this cyclic effect will continue, stabilizing the
settled organic solids during the warmer periods and continue to
produce both gas and soluble organic compounds.
342
-------
CHEESE PROCESS WASTEWATER LAGOONS
EPA - KENT CHEESE CO.
JAN 1971 - 1972
BOO
LOAD
1 K«
LDS.
day
TEMR
°C
D.O.
mg/l
OUVJ
500
v W
400
300
200
100
20
10
8
6
4
n
LAGOON PERFORMANCE
, . • •
y^\ '
OL ^T \^ M -. mi l^__^^ -^
;^*^^ ^^^x \ f , ~~~~--^ * ^*~~~~^^——^^-*^ * ^v
\r - . ' . v-^ .
.
*
* •
o
00° ° ° OOoO°°000
0 000 0
o o o
° 0
o rt o o o Q
rtOO ^%O O/N
°r,«000o° °00
- ' .... ' ' .
•
.* •• V- •"'•' •
* * * • •
. . * *- • • *
...".. H .*. .. -• .....
• • »*» •
* * • •* • *••••***
* *
» • • •* ••• • fl • •
* •••••••
1 1 1 ' 1 1 I 'J. * I ' — '••"f"'.. '..A _ I 'J *
JAN FEB MAR APR MAY JUNE JULY AUG SEPT OCT NOV DEC JAN
FIGURE 7
-------
The high oxygen demands occurring during the spring in waste stabilization
lagoons has been attributed to benthal digestion by a number of
investigators. Marais and Capri (1970) have attempted to estimate
the benthal demand in aerated lagoons. In a dynamic simulation of
data collected for domestic wastewater lagoons, they showed that the
rate of benthal decomposition was highly temperature dependent with
an estimated value of the temperature coefficient theta of 1.35. They
found that approximately 40 percent of the settled organic matter was
resolubilized for the domestic waste.
The one year period of this study was insufficient to adequately quantify
the benthal contribution to the lagoon organic load. The study period
was too brief to evaluate the effectiveness of the anaerobic digestion
in reducing accumulated sludge deposits. Steady state (or rather a
quasi-steady state) may occur only after a number of years. Yet based
on this and other studies, it is reasonable to report that oxygen
demands during the spring may exceed three to five times the applied
BOD5 load.
Dissolved oxygen concentrations in the secondary lagoon were normally
greater than 2.0 mg/1 even during the April-July period of anaerobiosis
in the primary lagoon. Only during two weeks in late June did dissolved
oxygen levels drop below 2.0 mg/1 and there was never a time when a
value of zero D.O. was recorded. Dissolved oxygen concentrations
were highest during the winter months, decreasing as oxygen uptakes
increased in the spring and summer months.
The results of BOD analyses in the two lagoons appear by quarter in
Table VI. The removal of BOD was strongly correlated with lagoon
temperatures reaching a maximum late in the summer and early fall.
Average BOD removal through both lagoons was 97.2 percent with the
poorest performance occurring in the winter quarter with a value of
95.1 percent. During the 4 1/2 month period, July 1 through November 15,
the effluent BOD did not exceed 30 mg/1 and was 20 mg/1 70 percent of
the time. Examination of the probability plots for total and soluble
BOD in the primary and secondary lagoon effluents (Figures 8 and 9)
indicates that the distributions of effluent BOD are skewed being
bounded at the lower end by the presence of organic matter relatively
resistant to biological degradation. Considerable scatter of effluent
BOD is demonstrated above the 50 percentile suggesting that, even with
very long detention times, the reliability of the system to turn out
high quality effluent at all times is very improbable.
It is of interest to note that the soluble fraction of the effluent
BOD represents on an average 50 percent of the total, with the highest
values occurring during the spring and summer quarters.
344
-------
TABLE VI
BOD ANALYSES
Kent Cheese Co. - EPA
Quarter
1971
Jan-Mar .
Apr-June
July-Sept.
Oct-Dec.
Aug.
In
Total
1975
1S80
1530
2100
1890
fluent
Soluble
1160
1030
870
1420
1140
P
Total
263
204
122
274
220
rimary Effluent
Soluble
56
45
37
42
45
% Rem*
Total
86.7
89.2
92.0
87.0
88.4
Total
98
61
21
31
52
Secondary
Soluble
48
32
13
14
27
Effluent
% Overall Rm.
Total-^
95.1
96.8
98.5
98.5
97.2
All values of BOD in mg/1
*BOD Removal based on total BOD
-------
CHEESE PROCESS WASTEWATER LAGOONS
EPA- KENT CHEESE CO.
JAN 1971-1972
PRIMARY POND EFFLUENT
ON
E
I
O
O
03
600
500
400
300
200
100
»«*»»*
0.1 0.5 12 5 10 20 30 40 50 60 70 80 90 95 98
FIGURE 8
-------
160
CHEESE PROCESS WASTEWATER LAGOONS
EPA-KENT CHEESE CO.
JAN 1971 - I97Z
140
120
IOO
E*
I 80
Q
60
40-
2O
FINAL EFFLUENT
J I
I
I I I I
XX***
I
O.I
0.5 I
10
20 30 40 50 60 70 80
90 95
FIGURE
-------
Figures10 and 11 illustrate the variations of BOD loading and lagoon
detention time throughout the one year period. The data presented
are compiled from running averages of approximately seven week
intervals, representing the minimum detention time in the lagoons.
Percent removals were estimated by examining effluent data approximately
one detention time delayed from influent data. Thus, percent removals
plotted represent the mean removal during the previous detention period
based on running averages.
Loadings to the primary lagoon varied from 0.93 to 1.97 Ib BOD/1000
cu ft/d, and from 0.08 to 0.29 Ib BOD/1000 cu ft/d in the secondary
lagoon. It was not possible to detect seasonal variations of primary
lagoon loading owing to the frequency of periods employed. Detention
time, however, did reflect a significant seasonal variation being
lowest during the summer months. Examination of Figures 10 and 11
suggest the advantages of staged lagoon operation. The secondary lagoon
definitely attenuated final effluent BOD concentrations throughout the
year even though primary lagoon effluents fluctuated widely. Again,
percent removals were apparently more dependent upon lagoon temperature
than either lagoon loading or detention time.
BOD Removal Rates - In order to quantify the observed BOD removal data
with lagoon detention time, a kinetic model was derived employing a
mass balance analysis. Because temperature directly affects the reaction
rate coefficient and because the detention periods in the lagoons
were long, no attempt was made to ascertain the precise order of the
reaction. Furthermore, oxygen dispersion data suggested that the
primary lagoon was well mixed, at least with respect to soluble BOD.
Finally, since volatile suspended solids were not correlated with
active biomass, no effort was made to employ a term for active biomass
in the kinetic expression. Based on these rather broad boundary
conditions, a relatively simple model was developed. Assuming a completely
mixed configuration, removal of BOD as a first order function in BOD,
and a steady state condition, the following expression is derived:
QLQ - QLe - kVLe - 0 (1)
and k - LQ - Lg ^ (2)
V
where k is the first order removal rate of BOD, I/days, t is detention
time, V/Q days, and Lo and Le are the BOD5 concentrations, mg/1, in
the influent and effluent, respectively. A temperature correction
348
-------
CHEESE PROCESS WASTEWATER LAGOONS
EPA - KENT CHEESE CO.
JAN 1971 - 1972
1 W
90
% R
BOD 80
70
2.0
w 1-8
£ Lb. BOD
I000cu.ft. 1.6
1.4
1.2
1.0
80
T
days 70
6O
PRIMARY LAGOON _ o o ^
o _ ® o _
O _ O On
°0 ° Oo
o
o
0 0
o
00 0 ° 0 ° 0
0 0 0 ° ° °
o Oo °° o o
0 oo
0 0 o ° °
0 0
0 0
00°°°
OOo 0
o o
O o °
1 1 1 1 I ° ° 1° 0 10 0 0 0, 0 , , , ,
JAN FEB MAR APR MAY JUNE JUDT AUG SEPT OCT NOV DEC JAN
FIGURE 10
-------
CHEESE PROCESS WASTEWATER LAGOONS
EPA - KENT CHEESE CQ
JAN 1971 - 1972
%R
BOD
L5.BOD
I000cu.fi
T
days
IV/W
90
SO
70
60
.30
.25
.15
.10
.05
80
70
60
50
SECONDARY LAGOON 0 ° A o 0 nn °n ^
o °°
ooooo ° °
°o oo o
o
00
0
0 °
o oo o
000oo00o° °0 °
0 0 0 0
o °°
o
^o ° oo
o° °
o _
! o 0°°00oOo0 o°
0 o0 o °
000°°°
JAN FEB MAR APR MAY JUNE JUCY AU6 SEPT OCT NOV DEC JAN
FIGURE
-------
for k may be obtained from the expression
T — T
k_ - k,_ 91! L2 (3)
L L
where k,., and k™ are the reaction rate coefficients at temperatures
Ll 12
T^ and !„ respectively, T is temperature in °C and 9 is the temperature
coefficient.
Values of k were calculated from the data based on running averages and
are presented in Figures 12 and 13. It is apparent that the values of
k are dependent upon lagoon temperatures. The increases in k during the
early spring may also be due to the resolubilization of degradable organic
matter from the benthal deposits. It is difficult to assess, however,
the reason for the very high increases in k noted in late July and
early August. Careful examination of the data indicates that the lowest
effluent BOD concentrations were recorded at this period, yet seven
weeks earlier (when influent BOD values were used to calculate values
of k) influent BOD values were high. Thus, slight shifts in the
selection of influent and effluent data for calculation of k values
greatly affected the average value of k during that period.
The soluble BOD removal rates were considerably higher than total
removal rates suggesting that a significant portion of the insoluble BOD
is more resistant to rapid decomposition. It is also apparent that
the secondary lagoon reaction rates are usually lower than those
in the primary lagoon. In general, the removal rates for soluble
BOD in the secondary lagoon were almost one order of magnitude lower
than for the primary lagoon whereas the total BOD removal rates in
the secondary process approached those in the primary lagoon during
certain periods of the year.
The influence of temperature on the rate of BOD removal is presented
in Figures 14 and 15. There are strong correlations between temperature
and total BOD removal rates in the primary lagoon as depicted in these
figures. A least squares fit of the data for total BOD indicates that
theta has a value of 1.085 for the primary lagoon and 1.026 for the
secondary lagoon. These values are within the range normally reported
for aerated lagoon systems. The rate of removal of BOD appears less
sensitive to temperature in the secondary lagoon because of differences
in the availability of organic matter going to that lagoon. Less
readily available organic matter discharged during the summer months may
conceivably result in lower rates of stabilization than during the
winter period. Also, this is evident for soluble BOD (Figure 15) where
it was not possible to evaluate a temperature coefficient for the
secondary lagoon.
351
-------
CHEESE PROCESS WASTEWATER LAGOONS
EPA - KENT CHEESE CO.
JAN 1971 - 1972
TOTAL
BOD .40
REMOVAL
RATE 30
per day
S SOLUBLE
BOD 1.00
REMOVAL
RATE
per day
TEMP.
°C
BOD REMOVAL RATES
and
LAGOON TEMPERATURES
PRIMARY LAGOON
running average
D.O. S0.0 mg/l
primary lagoon
JAN FEB
MAR APR MAY JUNE JULY AUG SEPT OCT NOV DEC JAN
FIGURE i2
-------
co
en
co
200
TOTAL 160
BOD
REMOVAL 120
RATE
x IO"3 80
40
SOLUBLE
BOO 60
REMOVAL
RATE 40
x JO'3
20
TEMR
°C
20
10
CHEESE PROCESS WASTEWATER LAGOONS
EPA - KENT CHEESE CO.
JAN 1971 - 1972
BOD REMOVAL RATES
and
LAGOON TEMPERATURES
SECONDARY LAGOON
running average
P.O. = 0.0 mg/l
primary lagoon
-oo
JAN FEB MAR APR MAY JUNE JULY AUG SEPT OCT NOV DEC JAN
FIGURE 13
-------
0.1
g
o .05
2E
UJ
-------
I.Or
0.5
CHEESE PROCESS WASTEWATER LAGOONS
EPA - KENT CHEESE CO.
JAN 1971-1972
O.I
LU
x - primary lagoon
<3>- no 0.0.
• - secondary lagoon
.05
UJ
a:
o
o
CD
UJ
_i
00
D
O
(O
.01
winter
summer
SOLUBLE BOD REMOVAL RATE
vs
TEMPERATURE
summer
.005
winter
.003
_L
8 (2
TEMPERATURE
FIGURE
355
16
20
24
-------
Suspended Solids - The performance of the lagoon system with respect
to suspended solids is considerably more difficult to quantify than
BOD. Influent suspended solids were high (Table VII) and contained
a large fraction of organic matter. Data was not available on the
settling properties of the influent solids and it was apparent that
suspended solids removals in the primary lagoon were very sporadic.
During the oxygen deficient period, primary effluent solids often
exceeded the influent solids level.
Again the advantage of staged lagoon operation was evident as final
effluent suspended solids were considerably more attenuated. The
probability plots (Figures 16 and 17), indicate that the effluent
suspended solids are not distributed normally, being rather widely
scattered at the high end of the distribution. The lowest values of
final effluent suspended solids occurred during the period July 1
through September 19. In this period, suspended solids concentrations
were less than 50 mg/1, 60 percent of the time. The average suspended
solids concentration in the final effluent was 108 mg/1 of which
91% was volatile matter (Table VII). It is interesting to note
that the solids discharged were predominately volatile, especially
during the July through December period. Furthermore, lowest
effluent solids occurred during the period when greatest algal growth
was evident.
The effluent discharge structure, as noted previously, was a vertical
standpipe with no baffling. Although no data was available, it is
reasonable to assume that baffles may significantly reduce suspended
solids discharges.
Solids Contributions to Effluent BOD - The data presented above
suggests that suspended solids play a significant role in the bio-
degradable organic matter discharged from the lagoons. A simple
mathematical expression for this contribution is:
Le(total) - Le(soluble) + C Se, (4)
where Se is the concentration of volatile suspended solids in mg/1, and
Le is the total or soluble 8005 in mg/1 and C is the fraction of the
volatile solids contributing to the 8005 (total).
Although not well correlated, there was an indication that approximately
62 percent of the VSS contribute to the total BOD in the primary lagoon.
This value is high and indicates that the primary lagoon solids are
not well stabilized. The contribution of VSS to the final effluent
BOD is also quite variable, the average value of C being 0.2. This
value is quite reasonable for lagoons of this type and algal contributions
to total BOD in this range are well documented.
Nutrient Levels - The nutrients, nitrogen and phosphorus were
determined monthly on composited samples collected from the raw
356
-------
TABLE VII
SUSPENDED SOLIDS ANALYSES
Kent Cheese Co. - EPA
tf
Quarter
Jan-Mar .
Apr-June
July-Sept.
Oct-Dec.
Avg.
Influent
Total
658
600
547
595
602
Volatile
614
569
520
565
567
Primary Effluent
Total
403
477
239
445
395
Volatile
335
390
197
377
328
% Remov.
(Total)
38.6
20.5
56.3
25.2
34.4
Total
155
119
43
111
108
Secondary Effluent
Volatile
143
103
43
110
98
% Overall Remova
(Total)
73.4
80.1
92.1
81.3
82.0
All values of suspended solids in mg/1
*S.S. removal based on T.S.S.
-------
900
CHEESE PROCESS WASTE WATER LAGOONS
EPA - KENT CHEESE CO.
JAN 1971-1972
800
700
PRIMARY EFFLUENT
600
I
u>
-------
400
CHEESE PROCESS WASTEWATER LAGOONS
EPA-KENT CHEESE CO.
JAN 1971 -1972
300
I
200
o
o
-------
wastewater stream and the secondary lagoon. The results of these
analyses appear in Table VIII. Examination of Table VIII indicates
that total phosphorus levels are high owing to the use of phosphate
base cleaners. A substantial amount of phosphorus was removed in the
pond system. It should be emphasized, however, that removal is the
result of sedimentation of the phosphorus and that eventually substantial
amounts of phosphorus will be resolubulized and be discharged in the
final effluent. Thus, during the one year period, it is doubtful that
a steady state with respect to phosphorus transformations has been
achieved and, likely, effluent levels may rise significantly over
those presently reported.
No data was available on the ammonia nitrogen levels in the system, but
it is apparent that total Kjeldahl nitrogen is very low with respect
to carbon. The BOD to Nitrogen ratio for the raw wastewater averaged
100:0.53, well below that normally required for adequate biological
growth (100:5). The substantial removals of total Kjeldahl nitrogen
through the pond system is indicative of both cell synthesis and
sedimentation. It is expected that nitrogen recycle would play an
important role in the biological system in these lagoons. Nitrate
nitrogen in the final effluent was normally low, but warmer temperatures
did result in significant nitrification between May and September.
An examination of lagoon temperature during these months (Figure 12)
indicate that when temperatures exceeded 20°C the rates of nitrification
did increase.
Coliform and Fecal Coliform - The sanitary wastewaters from the cheese
processing plant were discharged to the process sewers, thereby
requiring the installation of chlorination equipment for disinfection
of the final effluent. Both total and fecal coliforms were determined
from 'flow composited samples of the raw wastewater and final effluent
preceding disinfection. During this study, no chlorination of the
effluent was practiced.
Examination of Figure 18 indicates that better than 99.9 percent of
the total coliforms was achieved in the lagoons. Similarly, fecal
coliform counts which ranged from less than 10 to as high as 107 per
100 ml were reduced by greater than 99.9 percent throughout the study
period. Temperature did not appear to significantly influence coliform
disappearance in the lagoons during the survey period. In fact, although
there was considerable variation in effluent coliform numbers, there
was no apparent trend in disappearance rates.
Other Measurements - Values of pH and alkalinity were measured routinely
throughout the one year study. Raw wastewater pH values were highest
during January through May, averaging approximately 6.6, and then
decreased and leveled off to 6.2 for the remainder of the study.
Similarly alkalinities of the raw wastewater averaged 350 mg/1 during
the January through April period and then continuously decreased to
approximately 220 mg/1 in September. It is possible that process changes
or raw water quality accounted for these changes.
360
-------
OJ
TABLE VIII
NITROGEN AND PHOSPHORUS
EPA - Kent Cheese Co.
Date
1971
1-22
2-23
3-19
4-12
5-14
6-15
7-9
8-10
9-11
10-13
11-14
12-16
tog.
Day
Influent
Total
Phosphorus
F
Tu
F
M
F
Tu
F
Tu
Sa
W
Su
Th
BOD:
mg/1
37.0
35.0
41.3
7.4
32.5
76.9
15.5
33.0
68.4
55.7
04.6
42.6
45.0
N:P -
Ib/d
8.5
4.1
4.9
0.7
5.4
13.2
3.1
5.8
14.0
8.2
14.4
5.7
7.3
1900: 10
100: 0
Total Nitrate
Kjeldahl Phos. Nitrogen
mg/1
7.5
9.2
10.8
10.2
5.3
16.0
12.2
3.6
12.1
2.0
26.2
7.7
10.2
.2: 45
.53: 2
Ib/d
1.7
1.1
1.3
1.0
0.9
2.7
2.4
0.6
2.5
0.3
3.9
1.0
1.6
.0
.46
mg/1
0.1
1.0
0.1
0.4
0.4
4.4
0.1
0.1
0.1
0.1
0.1
2.7
—
Total
Phosphorus
tag/1
35.0
27.5
26.4
28.0
26.8
10.7
14.8
11.6
8.4
14.8
23.1
31.6
21.6
Ib/d
8.0
3.3
3.1
2.8
4.5
1.8
2.9
2.0
1.7
2.2
3.5
4.3
3.3
Effluent
Total Kjel-
dahl Phosph.
mg/1
4.0
5.9
5.5
6.0
10.6
4.2
1.5
1.0
1.1
0.2
1.8
4.2
3.8
Ib/d
0.9
0.7
0.7
0.6
1.8
0.7
0.3
0.2
0.2
0.0
0.3
0.6
0.6
Nitrate
Nitrogen
mg/1
0,3
0.5
0.2
0.4
1.9
24.4
3.4
4.0
1.4
0.4
0.4
0.2
— '
-------
CHEESE PROCESS WASTEWATER LAGOONS
EPA - KENT CHEESE CO.
JAN 1971 - 1972
8
10
107
E
O
O
$ " io6
a:
ui
a.
g 10*
u.
8
102
LAGOON PERFORMANCE • •
INFLUENT
<- less than value
T
SECONDARY EFFLUENT
i i i I
I 1
J I
JAN FEB MAR APR MAY JUN JUL AUG SEPT OCT NOV DEC JAN
FIGURE 18
-------
The lagoons exhibited higher pH values (7.4 to 7.5), being the highest
during the first one half of the year (January through June), and
then sharply decreased to a value of 7.2 for the remainder of the study.
Alkalinities ranged from about 380 mg/1 to as high as 510 mg/1 during
the year. No correlation was noted between pH and measured alkalinity
and there was no particular trend in alkalinity values during the year.
It is assumed that changes in algal activities and microorganism
respiration influenced these variations, but no data was available on
algal activities to document these variations.
Settleable solids were monitored daily on the raw wastewater and on the
primary and secondary lagoon effluents. Settleable solids in the raw
wastewater ranged between 0.1 and 5 ml/liter during the one year study,
normally being less than 1.0. Secondary lagoon effluents never
demonstrated significant amounts of settleable solids, but the primary
lagoon effluent was high in settleable solids from mid-May through
mid-July. Values as high as 120 ml/liter were recorded during this
period when dissolved oxygen concentrations were zero. Floating mats
of solids and rising sludge were noted throughout this period. Once
dissolved oxygen was maintained in this lagoon, the settleable
solids decreased to an immeasureable amount.
Cost - The annual costs associated with the Kent Cheese Co. wastewater
treatment facilities are based on operating and maintenance costs
consisting of electric power requirement, repairs, operator costs,
and administration. Annual capital costs are based on an interest
rate of 7 1/2 percent for mechanical and equipment amortized over a
five year period and costs associated with lagoon construction over a
30 year period. The annual costs do not include those costs associated
with the post construction studies which are not representative of
normal operating expenses. A summary of the costs related to annual
operation of these treatment facilities are presented below:
Construction Costs
*in nni in Annual Costs
Contract $29,097.10
Engineering
Pre Construction Report 500.00
Plans 3,387.14
Construction Superv. 916.00
sub total $33,900.24
(i - 7.5% 30 yr) $2,870.00
Mechanical Equipment 14,807.18
(i = 7.5% 5 yr) 3,661.00
sub total $6,531.00
Operating and Maintenance Costs
Electric Power $2,477.71
Repairs 2,969.00
Operator 1,254.33
Administration 144.60
sub total $6,845.64
Total Annual Costs $13,376.64
363
-------
These cost estimates were prepared for a period of operation soon after
construction was completed and the operating costs reflected in the
category of repairs may be higher than may be expected on an average
basis. In addition, the costs for analytical services in conjunction
with the post construction studies were not included in the cost
estimate but some additional operating costs will be necessary for
routine chemical analysis necessary for reporting to regulatory
agencies. Thus, it is expected that these two factors may tend to
compensate each other and the estimate provided is indicative of
costs associated with this treatment method.
The annual cost prorated to pound of BOD applied or 1000 gallons of
wastewater treated are $0.14 per pound of BOD and $2.15 per thousand
gallons respectively. Based on cheese produced, the annual cost is
approximately 0.33c per pound.
364
-------
CONCLUSIONS
The conclusions summarized below are the result of the analysis of
data collected over a one year period from the two-stage aerated
lagoons treating cheese processing wastewaters for the Kent Cheese
Company.
Each of the two lagoons are of equal volume and provided detention
times of from 50 to 82 days each during the first year of study. The
average flow to the lagoons was 17,000 gal/day providing a BODe
loading of 270 Ibs/day. Organic loading to the primary lagoon varied
from 1.0 to 2.6 lbs/1000 cu ft/day.
1. Aerator Performance
a. The oxygen transfer efficiency of the Polcon Corporation
Helixors in the primary lagoon was 4.0 Ibs oxygen/kw-hr
or 3.0 Ibs oxygen/hp-hr, for standard conditions (20*C
tap water, zero dissolved oxygen) at an air flow rate of
14.8 scfm per unit.
b. Doubling the air flow rate per unit substantially reduced
the oxygen transfer efficiency.
c. The dispersion of oxygen in the primary lagoon at a power
input of 8.5 hp/MG was nearly uniform.
d. At the power input of 8.5 hp/MG, there was a tendency for
suspended solids to accumulate in the peripheral regions
where horizontal velocity components were normally less than
0.1 fps. The one year study was not long enough to evaluate
fully the rate of solids accumulation within the lagoon.
e. The relative oxygen transfer coefficient in the primary
lagoon was approximately 81 percent of that expected in
tap water. The oxygen saturation value in the primary lagoon
content was approximately 98 percent of that in pure water.
2. Lagoon Performance
a. An average of 97.2 percent removal of BOD~ was achieved in
the two stage aerated lagoon system with the poorest
performance (95.1 percent) occurring during the winter
season. The average final effluent BOD_ concentration was
52 mg/1 of which 27 mg/1 was soluble. Probability distribu-
tions for treatment performance were prepared for the one
year study.
365
-------
b. A simplified model of lagoon performance was derived based
on complete mixing in the lagoon and first order removal
of BOD5.
c. Temperature had a significant effect on lagoon performance.
Values of the temperature coefficients for BOD removal rates
were graphically determined for both primary and secondary
lagoons.
d. Suspended solids removals in the primary lagoon were sporadic.
The overall average removal of suspended solids in the lagoon
system was 82 percent with an average concentration of
108 mg/1 in the final effluent. Over 90 percent of the
suspended solids were volatile.
e. Approximately 20 percent of the volatile suspended solids
in the final effluent contributed to the total BOD,.. A
similar relationship for the primary effluent suspended
solids indicated that 62 percent of the.volatile suspended
solids contributed to the BOD..
f. High oxygen uptake rates occurring in the early spring
resulted in zero D.O. concentrations in the primary lagoon.
These high uptake rates are likely due to the solubilization
of solids deposited during the winter months. The cycling
of sludge accumulation during the cold periods and active
biological stabilization of the benthal deposits during the
warmer months will result in dynamic fluctuations in oxygen
requirements and sludge deposits. Aerator sizing to account
for these fluctuations must be provided. In this study
oxygen demands in excess of four times the BOD. were measured
during the early spring.
g. The staging of the watewater treatment lagoons provided
considerable attenuation of the fluctuating BOD and solids
concentrations in the primary lagoon effluent.
h. Total and fecal colifonn reductions exceeded 99.9 percent
in the two stage lagoon system.
i. Nitrogen concentrations in the raw wastewater were low
with respect to carbon. The BOD to Nitrogen ratio was
100:0.53 indicating a substantial deficiency in nitrogen.
Phosphorus concentrations were high resulting in a BOD:P
ratio of 100:4.5.
j. Total phosphorus removals of 52 percent observed during the
366
-------
one year study may be misleading insofar as a steady
state with respect to phosphorus transformations has
probably not been established. Total organic nitrogen
removal of 47 percent were observed. Nitrate concentrations
in the final effluent were highest during the warm summer
months but were less than 0.4 mg/1 during the rest of the
year.
3. Costs
The unit cost for wastewater treatment during the first year of
operation was $2.15 per 1000 gal., $0.14 per Ib BOD applied, and
$0.0033 per Ib of cheese produced.
367
-------
RECOMMENDATIONS
Based on the operation of the two stage cheese processing wastewater
lagoons at Kent, Illinois, the following recommendations have been
proposed:
1. Efforts should be made to further reduce the settleable solids
input to the lagoons. These solids cause clogging problems at
the inverted siphon, interfere with flow measurement and sampling
at the primary lagoon and result in increased BOD loading to the
primary lagoon. Insofar as solubilization of settleable solids
during the warm months has resulted in severe depressions in
dissolved oxygen concentrations in the primary lagoon, every
measure taken to reduce influent settleable solids will help to
alleviate that problem. It is suggested that a settling tank or
Imhoff tank be provided ahead of the primary lagoon for this
purpose.
2. The high air pressures observed during dual compressor operation
suggests that the air headers and inlet orifices are undersized
for the increased air flow rates. Since oxygen uptake rates
during the spring and early summer exceed current oxygen transfer
rates, it is recommended that investigations be made to determine
the necessity for enlarging existing air piping or providing
additional Helixors in the primary lagoon.
3. The increased oxygen uptake rates in facultative aerated lagoons
during the spring have been reported by a number of investigators.
Further investigation should be conducted to provide a quantitative
estimate of this increased demand. Such a study would require
data collection over a number of years at the existing aerated
lagoon site.
4. Nitrogen deficiencies in the raw wastewater will normally result
in poorer performance of the biological system. It is recommended
that additional nitrogen be added as ammonia or urea to more
closely approximate the BOD to Nitrogen ratio of 100 to 5.
Comparisons in Iggoon performance should be noted during this
period (at least one full year) so as to evaluate the value of
this supplimentation.
5. The secondary lagoon effluent structure consists of only an
upturned 4 inch cast iron pipe elbow. It is recommended that this
effluent structure be modified so as to provide some baffling to
eliminate gross solids and scum entrainment.
368
-------
ACKNOWLEDGEMENTS
This study was supported by the Environmental Protection Agency,
Project No. 12060 EKQ and the Kent Cheese Co., Kent, Illinois.
The authors wish to acknowledge the technical assistance and
support of Mr. Fran Daul, Kent Cheese Co., and Mr. Max Cochrane,
E.P.A., Northwest Regional Water Laboratory, and the field and
laboratory support of Mr. Lome Grannns, Mr. Jack Quigley, and
Mr. Tom Jensen from the University of Wisconsin.
LITERATURE CITED
Marias and Capri, M.J., "A Simplified Kinetic Theory for Aerated
Lagoons", Second International Symposium for Waste
Treatment Lagoons, Kansas City, Missouri, pg 299, June 1970.
369
-------
APPENDIX A
Calculation of Oxygen Transfer Rate
November 19, 1970
Lagoon No. 1 (Primary Lagoon)
Average Oxygen Uptake Rate - 2.05 mg/l/hr =17.8 Ib/hr
Temp. - 6.3°C
Dissolved Oxygen =2.9 mg/1
1 compressor - 30 amps at 220 v » 6.6 kw
Air Distribution to Primary Lagoon - 80Z
Field Transfer:
M _ 17.8 Ib/hr
6.6 kwx 0.8
_ ,_
3'32
Standard Transfer:
N - N Cs _ T-20
( C - C) 9
S
C at 20'_ - 9.2(Jjb + Q+ )
S C (29.4 ~42~)
09 .U.7 + 12/2.3 . 18.3
9-2 ( 29T4 •*" ~42~
C - 9.2 (0.68 + 0.5)
20°
-10.8 mg/1
C - 14.8 mg/1 0 12' depth
S6.3°C
a- 0.75, 3 = 0.96, 0 = 1.02
N - 3.32 [ __ 10.8 ____ ]
[0.75(0.96 x 14.8 - 2.9) 1.02 ]
N - 5.55 Ib/kw-hr
S
N » 4.14 Ib/hp-hr
S
*where depth = 12* and estimated transfer efficiency is 10%
370
-------
CHARACTERIZATION AND TREATMENT OF BREWERY WASTES
*"*
Henry G. Schwartz, Jr.* and Richard H. Jones
INTRODUCTION
The "brewing industry in this country has grown steadily in recent years,
with total production in 1971 amounting to 135 million "barrels (Mbbl)
(l). A marked change in the character of the industry has accompanied
this growth. Where the industry once consisted of many small local
breweries, it is now increasingly dominated by a relatively small number
of regional and national brewers. Most of the small breweries have
either been absorbed by the larger firms or have ceased operating entire-
ly in the face of strong competition.
As the nature of the industry has changed, so have the individual brew-
eries. The smaller facilities are inefficient and the cost of moderni-
zation is prohibitive. These breweries are being abandoned and new plants
with much greater capacities are being constructed. Twenty years ago
there were only a few breweries with capacities over 1.0 Mbbl/year while
today virtually every new brewery has a capacity in the range of 1.5 to
4.0 Mbbl/year.
This trend to larger breweries creates fewer, but much more substantial
waste sources. These high-volume, high-strength wastes give rise to
difficult pollution abatement problems, particularly in view of increas-
ingly stringent effluent standards.
The purpose of this paper is two-fold, first to review brewery waste
treatment practices throughout the country and, secondly, to present the
results of pilot plant studies at one specific location. In so doing,
it is hoped that future brewery waste treatment designs will benefit from
past experiences.
WASTE CHARACTERISTICS
Brewery effluent can generally be characterized as high-strength organic
wastes with moderately high suspended solids concentrations. The wastes
are generated from a number of plant operations as indicated in the
accompanying flow diagram, Figure 1.
*Head, Environmental Engineering, Sverdrup & Parcel and Associates,
Inc., St. Louis, Missouri
**Vice President, Environmental Engineering, Inc., Gainesville,
Florida
371
-------
MTU ILL until Eguincirr
KQOIKS UOTTIC UO/M KID.
MIT 1 MM
BlJfCJil.
»»JTC ICtl. HOSE MTH,
CUMIIG »IVTIOM. ETC.
FIGUEE 1 BASIC BREWERY
FLOW DIAGRAM
372
-------
Beer has a BOD of about 100,000 to 150,000 mg/1 and, thus, one 12-oz
"bottle of beer has just a little less BOD than the daily per capita
domestic waste load. Wash-water from the various "brewing vessels, gen-
eral plant washdown, and waste beer from breakage and spillage in the
packaging lines, therefore, contribute large waste loads.
Perhaps the largest single waste source is press liquor from grain dry-
ing. Spent grain from the lauter tun is normally sold as feed. Rather
than sell the wet grain slurry, some brewers elect to partially dry the
spent grain using large mechanical presses. The liquor from these
presses has a very high BOD content and may constitute 25 percent or
more of the total plant BOD load.
The effluent characteristics from ten breweries are given in Table 1.
The data presented in this table were collected during plant visits,
supplemented by limited information in the literature (2) (3) (4), and
demonstrate the high BOD and suspended solids levels in brewery wastes.
Those breweries with relatively low BOD levels generally do not press
the spent grains, although the concentration depends also on water usage.
Water consumption in the industry ranges from 5 to 15 bbl/bbl of beer.
Individual waste parameters fluctuate considerably over the brewing day
because of the batch type of operation. Wide variations in pH result
from the use of sulfuric acid, sodium hydroxide, and other cleaning com-
pounds. Measurements taken at Brewery A, Figure 2, show changes of
10 pH units within a 30-minute period. A pH of about 4.0 was observed
for a three-hour period while the 24-hour composite had a pH of about
6.0.
Other data gathered at Brewery A, see Table 2, indicated a COD:BOD ratio
of about 2:1, but this factor was somewhat variable. Soluble BOD con-
stituted about 75 percent of the total BOD. Dissolved solids concentra-
tions averaged 1520 mg/1 with peak values up to 2190 mg/1.
PRESENT WASTE TREATMENT PRACTICES
The current state-of-the-art in brewery waste treatment is much less
advanced than might be anticipated. Most breweries discharge their
wastes into large municipal sewerage systems in which the specific
effects of the greatly diluted brewery wastes are difficult to ascer-
tain. At least nine treatment plants throughout the country are pres-
ently known to receive a substantial proportion of brewery wastes in
their total flow. For purposes of this discussion, a substantial pro-
portion is defined as ten percent or more by volume. Four of the nine
plants currently receive only brewery wastes.
During the course of these studies, each of the nine plants was visited
at least once. A brief description of the nine treatment facilities is
presented in Table 3. All of them have experienced varying degrees of
difficulties in treating the brewery discharges.
373
-------
TABLE 1
BREWERY EFFLUENT CHARACTERISTICS
Brewery
A
B
C
D
E
F
G
H
I
J
Total
Flow
mgd
2.7
3.4
1.2
0.35
0.85
3.2
1.5
1.0
5.6**
1.6
Average
BOD
mg/1
1000-1400
900
850
2000-2300
2800-2900
1500-2200
6000-8000
2100-4300*
1000**
980
Peak
BOD
mg/1
2700
-
4800
-
5000
5000
11,000
19,000*
-
_
Average
Suspended
Solids
mff/1
500-700
500
-
800-1400
700-1600
200-400
2600-2700
-
450**
365
m
3-12
3-14
2-12
-
-
-
-
-
2-12
_
*COD
**Design values
374
-------
12-r
10-
8 -
6 -
2 -
H 1 1 h
5 6 78
NOON I
10 II 12
12-
10--
8 .-
6 •
2 -I-
I
r\
H 1 1 h
H h
—«—i—i—\—i
15 16 17 18 19 20 21 22 23 NOON
T I M E - H R S .
FIGURE 2 pH FLUCTUATIONS OF RW BREWERY WASTE
12 13
375
-------
TABLE 2
WASTE CHARACTERISTICS - BREWERY A
Characteristic Operating Data*
Flow - average 2.65 mgd
BOD - average 1000-1400 mg/1
range 400-2700 mg/1
Suspended solids - average 500-700 mg/1
range 140-1340 mg/1
Temperature - average 94°F
range 88-102°F
pH - average 5.5-6.2
range 3-12
**Dissolved solids - average 1520 mg/1
range 770-2190 mg/1
**COD - average 2290
range 560-3800
**COD:BOD ratio 2.0:1
^Soluble BODrTotal BOD ratio 0.75:1
*Based on six-month operating record except as otherwise noted
**Results of eight-day sampling program during plant evaluation
study
376
-------
TABLE 3
WASTE TREATMENT PLANTS HANDLING BREWERY WASTES
Treatment
Plant
(Brewery)
••o
Waste
Treatment
Sequence
Clarifier
roughing filter,
activated sludge
(contact stabilization),
clarifier,
chlorination
Grit chamber,
clarifier,
activated sludge
(Kraus process),
clarifier,
chlorination
Settling basin,
activated sludge
(Kraus process),
settling basin
Grit chamber,
settling basin,
activated sludge
(Kraus process),
settling basin,
chlorination
Sludge
Disposal
Sequence
Aerobic digestion
sludge lagoon
Storage,
flotation,
vacuum filtration,
land disposal
Anaerobic digestion,
drying beds,
land disposal
flotation,
anaerobic digestion
sludge lagoon
Total
Flow,
mgd
2.65
4.6
0.70
Brewery
Flow,
mgd
2.65
3.4
1.2
0.35
Approximate Treatment
Efficiencies, percent
Suspended
BOD Solids
80-85
30-70
90
85-90
94
90
92
-------
TABLE 3 cant
WASTE TREATMENT PLANTS HANDLING BREWERY WASTES
Treatment
Plant
(Brewery)
E
00
Waste
Treatment
Sequence
Pretreatment
(brewery wastes)
equalization basin,
clarifier,
roughing filter,
clarifier,
trickling filters,
clarifier,
lagoons
Equalization basins,
clarifier,
roughing filter,
activated sludge
(conventional),
clarifiers,
chlorination
Clarifiers,
trickling filters,
activated sludge,
settling basins
Sludge
Disposal
Sequence
Thickener
anaerobic digestion
drying beds,
land disposal
Total
Flow,
roed
8.5
Flotation,
thickeners,
vacuum filters,
land disposal
Anaerobic digestion
drying beds,
kiln drying,
sale as fertilizer
3.2
20
Brewery
Flow,
roed
0.85
Approximate Treatment
Efficiencies,, percent
Suspended
BOD Solids
60-70
35-60
3.2
1.5
-------
TABLE 3 cant
WASTE TREATMENT FT.&NTS HANDLING BREWERY WASTES
to
Treatment
Plant
f Brewery)
H
Waste
Treatment
Sequence
Grit chamber,
clarifiers,
roughing filters,
activated sludge
(contact stabilization),
clarifiers,
lagoon
Clarifiers,
activated sludge
(complete mix),
clarifiers,
chlorination
Sludge
Disposal
Sequence
Aerobic digestion,
sludge lagoons,
spray irrigation
Thickeners,
spray irrigation
Total
Flow,
med
1.0
9.6*
Brewery
Flow,
mad
1.0
5.6*
Approximate Treatment
3Lf ficienciea f percent
Suspended
JBOD Solids _
95
95
90+
^Design values
-------
Activated Sludge Systems
Eight of the nine treatment plants use some form of the activated sludge
process. The Kraus process or a modification thereof is used at three
older installations, B, C, and D. Interestingly, these three systems
•were all originally designed and/or operated as conventional activated
sludge systems and were later converted to the Kraus process. In each
case, sludge "bulking "became a major problem when the conventional sys-
tem was used. The Kraus process has "been the only successful means of
controlling "bulking at these plants. Chlorination of the return sludge
for control of filamentous organisms was tried at one location without
success. As used at Plants B, C, and D, the Kraus process has generally
proved to be an effective method for treating brewery wastes. It should
be noted, however, that these three systems also receive municipal wastes.
The only complete-mix activated sludge system, Plant I, has been in ser-
vice only a few months and operating data are unavailable. Presently,
the treatment plant receives only brewery wastes although municipal wastes
will soon be added. Because of the low flows, the detention time in the
force main is about six hours and the waste is septic when it arrives at
the treatment facility. The resulting odors are very prevalent near the
primary clarifiers.
The complete-mix system at Plant I was designed for a food:microorganisms
ratio of less than 0.4 Ib of BOD removed/lbs mixed liquor suspended solids.
A chlorination system for the return sludge has been provided to control
sludge bulking should it occur. To date, no such problems have arisen;
however, the true test will not occur until the system approaches design
loadings.
On three occasions, acid conditions in the influent waste stream, i.e.,
pH values below 4.0, have killed the activated sludge system. Such dis-
charges are now being neutralized at the brewery. The thickener appar-
ently has very little effect on the waste activated sludge. BOD levels
in the effluent are reported to be below 25 mg/1, but the secondary
clarifier overflow has a noticeable suspended solids content.
A conventional plug-flow activated sludge system is used at Plant F,
which has been in operation for about two years. In spite of equaliza-
tion basins, nutrient addition, and a roughing filter ahead of the acti-
vated sludge system, severe sludge bulking has occurred as it has at
many brewery waste treatment plants. Anaerobic conditions, causing
rising sludge, clearly exist in the primary clarifiers, and the combined
primary and waste activated sludges cannot be thickened in the conven-
tional gravity unit. Fortunately, the flexibility and large capacity of
the treatment system will enable some of these problems to be solved by
operational changes.
Plants A and H employ contact stabilization following roughing filters.
The contact stabilization process is particularly suitable for wastes
with high proportions of suspended and colloidal BOD, but its applica-
tion to the highly soluble BOD waste from breweries warrants examination.
380
-------
The overall treatment efficiencies at Plant A have "been below expecta-
tions, with BOD removals of about 80 percent and suspended solids reduc-
tions in the 30 to 70 percent range. Studies at the plant show an
effective loading rate of 0.78 Ib BOD/lb MLSS based on contact and re-
aeration tank volumes. Sludge bulking is a periodic problem at this
very high loading rate, as evidenced by poor suspended solids removals.
Modifications are presently being made to this treatment system in
accordance with the results of pilot plant studies to be discussed in
a subsequent section.
Plant H is very similar to Plant A in the basic process sequence, but
the results at Plant H are markedly superior. This facility has been
in operation about l-^ years, with treatment efficiencies well above
90 percent. The excellent performance can be attributed to several fac-
tors, not the least of which is the in-house control exercised by the
brewery. Press liquor is pumped to a holding tank and fed to the treat-
ment plant at a constant rate seven days a week. Similar controls are
practiced for spent caustic solutions.
A second factor contributing to the performance is a ten-acre polishing
lagoon with a 15-day minimum detention time. The lagoon follows the
main treatment operation and serves as added insurance against plant up-
sets. In fact, it was observed that the effluent from the secondary
clarifiers contained appreciable suspended solids which were later re-
moved in the lagoon.
The final major factor influencing the plant performance is the fact
that the present loading on the plant appears to be well below design
levels. The design was based on a BODtMLSS ratio of 0.38.
Trickling Filter Systems
Conventional trickling filters for complete secondary treatment have been
used in the past at Plants D, E, and G. The trickling filter at Plant D
was abandoned in favor of the present Kraus system after several years
of difficulty. Plant E currently uses two large filters in series to
handle the combined domestic and pretreated brewery wastes. The overall
treatment efficiencies are 60 to 70 percent for BOD and 35 to 60 percent
for suspended solids. Plant G recently upgraded its trickling filter
system by adding activated sludge in series to the treatment sequence
and by covering the filters with styrofoam domes to contain odors. Un-
doubtedly, the extensive modifications to Plant G have significantly
improved treatment performance, but data on the new system are not
available. The performance of trickling filter installations handling
brewery wastes has been mediocre at best. Treatment efficiencies have
been well below current acceptable levels and offensive odors have
compounded the problems.
Plastic media trickling filters are used as roughing units at four loca-
tions, Plants A, E, F, and H. The purpose of these roughing filters,
designed to remove 45 to 60 percent of the BOD, is to reduce the high-
strength of the influent brewery wastes to more manageable levels.
381
-------
Generally, the roughing filters seem to have met the design crittsj. j.«.,
but not without some problems. With the exception of Plant H, the fil-
ters all generate objectionable odors, at times discernible for several
miles. The septic nature of the waste as it leaves the primary clari-
fier and the anaerobic conditions in the roughing filter result in
significant odor generation. Measurements at two of these plants show-
ed zero dissolved oxygen in the wastes throughout the roughing filters.
Little or no odor can be detected from the roughing filters at Plant H,
possibly a reflection of lower loading rates at present.
Sludge Disposal
The disposal of primary and secondary sludges from brewery waste treat-
ment operation is a severe problem, as it is at many treatment plants.
The high BOD and suspended solids content of brewery wastes, however,
results in a much higher solids production per unit volume of waste than
many other wastes. A variety of sludge disposal methods have been used
for brewery wastes with mixed results.
Gravity thickening has been used with little success on both combined
and waste activated sludges. Three plants presently use dissolved air
flotation for thickening waste activated sludge with similar results,
specifically a discharge solids content of about three to four percent.
Plants C, D, E, and G, use anaerobic digestion as their main sludge dis-
posal method. The digestion systems perform quite satisfactorily in
terms of volatile solids reductions, but little solids separation is
achieved in the second stage digesters. Three of the four plants use
sludge drying beds, while the digester liquor from Plant D is discharg-
ed to a sludge lagoon which creates odor problems, particularly in the
spring. Notably, the percentage of brewery wastes and, hence, brewery
sludge is much higher at Plant D than at the other plants using anaer-
obic digestion.
Aerobic digestion is used at Plants A and H, but is soon to be replaced
with incineration at the former. Insufficient digestion capacity at
Plant A resulted in only partial digestion and stabilization. Both
plants initially discharged the digested solids to sludge lagoons, but
severe odor problems eventually forced an end to this practice. The
application of lime, masking agents, and other chemical controls failed
to eliminate or even markedly improve the situation.
Plant H is now experimenting with spray irrigation for disposing of the
digested sludge. Spray irrigation is also used at Plant I, but without
digestion.
Plants B and F use vacuum filters and dispose of the filter cake in
landfills. A thermal sludge-conditioning unit was installed about two
years ago at Plant B to reduce or eliminate the high operating cost of
chemical conditioning. At the same time, the heat-treatment decant
liquor was substituted for digester liquor in the Kraus process. The
high strength, resolubilized BOD in the decant liquor apparently over-
loaded the activated sludge system and caused a precipitous drop in the
382
-------
overall plant efficiency. Moreover, the heat treatment process generat-
ed very objectionable odors. , Within six months, the carbon steel heat
exchanger failed as a result of corrosion and the system was abandoned.
Interestingly, while the system was in service it yielded a filter cake
with about 40 percent solids with no chemical conditioners. This result
is to be compared with a 15 percent solids content in chemically condi-
tioned filter cake using 15 to 20 percent lime and 7 to 9 percent ferric
chloride at the same plant.
PILOT PLANT STUDIES
Since system start-up in 1969, Plant A has experienced a series of oper-
ational difficulties, some of which have been discussed previously. A
flow diagram of the treatment system, previously described in Table 3,
is shown in Figure 3. The treatment plant receives only brewery wastes
at present, although domestic wastes will be added in the near future
at about a 1:1 ratio.
One of the major concerns at Plant A has been the inability of the system
to consistently achieve satisfactory treatment levels. Extensive field
studies of the existing system indicated that the contact stabilization
process was poorly suited to the high soluble-BOD nature of the brewery
wastes, especially at the very high loading rates experienced, i.e.,
0.78 Ib BOD/lb MLSS.
As a result of these problems, a series of pilot plant studies were
undertaken to evaluate the treatability of the waste using the complete-
mix activated sludge process. Studies were conducted with raw brewery
wastes, trickling filter effluent, and a mixture of domestic and brew-
ery wastes. In addition, a brief experiment was run on aerobic sludge
digestion. Results from the pilot plant studies are presented in the
following sections.
Experimental Facilities
The field studies conducted at the Plant A site were in two pilot units.
Pilot Plant No. 1 consisted of a 650 gal, 18.0 ft2 surface area primary
clarifier; a 1,970 gal aeration tank; and a 512 gal, 16.0 ft2 surface
area secondary clarifier. Pilot Plant No. 2 consisted of a 140 gal,
6.0 ft2 surface area primary clarifier; a 419 gal aeration tank; and a
140 gal, 6.0 ft2 surface area secondary clarifier. Air for the aera-
tion tanks and sludge return lines was provided by individual compres-
sors for each unit.
Samples were composited by automatic sampling devices where feasible
and most chemical analyses were conducted on site in a mobile labora-
tory. All tests were conducted in accordance with Standard_Methpds for
the Examination of Water and WastewaterT 12th Ed., with the exception
of dissolved oxygen, which was measured by a dissolved oxygen probe
calibrated against the standard Winkler titration.
383
-------
recycle
Primary
Clarifier
Division Box &
PH Adjustment
off-gas
Ozonator
Effluent
To
SIudge
Disposal
Secondary
Clarifier
FIGURE 3 WASTE TREATMENT FLOW DIAGRAM FOR BREWERY A
384
-------
Treatment of Raw Brewery Waste
Pilot Plant No. 1 was used for the experiments on the treatment of raw
brewery waste. The unit was placed into operation by filling the aera-
tion tank with settled brewery waste and seeding with 600 gallons of
return activated sludge from Plant A. The activated sludge system was
acclimated stepwise over a 17-day period to an hydraulic feed rate of
1500 gal/day, which gave an average loading rate of 0.21 Ib BOD/lb MLSS.
Ammonium nitrate was added to supplement the low level of nitrogen,
about 1-6 mg/1 as N, in the influent waste.
After the system was stabilized, 24-hour composite samples were analyzed
over an eight-day period. Subsequently, the average loading rate was
increased to 0.56 Ib BOD/lb MLSS and samples were collected and analyzed
for an additional 12-day period. The data gathered during these experi-
ments are summarized in Table 4 for runs Al and A2 and are presented
graphically in Figures 4 and 5.
The results of these pilot plant studies indicate that raw brewery waste
can be easily biodegraded by the complete-mix'activated sludge process.
At the lower loading rate of 0.21 Ib BOD/lb MLSS, the soluble BOD in the
effluent was always less than 20 mg/1 and averaged 8.0 mg/1. At the
higher rate of 0.56 Ib BOD/lb MLSS, the effluent soluble BOD averaged
14 mg/1.
The soluble BOD removal rate, K2, was calculated based on the equa-
tions ( 5) :
Lo - Le „ 0 .
Le = K2 Sa t
K2 =
where; K2 - removal rate constant
Lo = influent soluble BOD
Le = effluent soluble BOD
Sa = mixed liquor suspended solids
t = time under aeration, detention time
6 = 1.056 (20° to 30°C)
© = 1.135 (4° to 20°C)
Average values calculated for the several runs are given in Table 5.
In view of past experience with sludge bulking, one of the major items
of interest in these studies was the sludge volume index (SVI). The
SVI averaged 230 for the lower organic loading rate and 346 at the high-
er rate. A sludge with an SVI of 230 can be settled in a conservatively
designed secondary clarifier, but it is difficult to achieve adequate
liquid-solid separation consistently with an SVI of 346.
385
-------
CO
00
TABLE 4
SUMMARY OF PILOT PLANT RESULTS
Constituent Averages
Pilot
Plant
Run
Al
A2
A3
M
A5
Feed
Type
Brewery waste-
Primary effluent
Brewery waste-
Primary effluent
Brewery waste-
T. F. effluent
Brewery waste-
T. F. effluent
Brewery waste-
T. F. effluent plus
settled domestic
sewage 1:1
BOD Loading
Ib BOD/lb MLSS
Total Soluble
0.21 0.14
0.56 0.39
0.18 0.13
0.54 0.34
0.32
Sampling
Point*
Influent
Effluent
Influent
Effluent
Influent
Effluent
Influent
Effluent
Influent
Effluent
Total
Suspended
Solids
raff/1
262
25
415
136
192
22
346
190
209
37
BOD
Total
raff/1
1,151
10
1,260
38
403
18
451
83
432
35
Soluble
raff/1
812
8
974
14
294
6
304
33
10
COD
Total
me/1
2,350
77
2,062
189
797
75
889
267
734
113
* Influent to activated sludge tank and effluent from secondary clarifier.
-------
1,900
1
8
TIME-DAYS
FIGURE 4 BOD REDUCTION IN PILOT PLANT TREATING SETTLED
BREWERY WASTE. AVERAGE LOADING RATE - 0.21 Ib
BOD/lb MLSS/day
387
-------
LU
CO
TIME-DAYS
FIGURE 5 BOD REDUCTION IN PILOT PLANT TREATING SETTLED
BREWERY WASTE. AVERAGE LOADING RATE - 0.56 Ib
BOD/lb MLSS/day
388
-------
00
TABLE 5
SOLUBLE BOD REMOVAL RATE CONSTANTS
Pilot
Plant Lo, Le, Sa, t, Lo/Sat, Ka, T, Ka,
Run mg/1 mg/1 rog/1 days lb BOD/lb MLSS 1/gm-hr ^C 1/gm-hr
Al
A2
A3
A4
812
974
294
304
8
14
6
33
3870
2770
4030
2510
1
0
0
0
.51
.95
.60
.36
0
0
0
0
.14
.39
.13
.34
0.
2.
1.
0.
92
07
44
58
18
20
19
22
0.96
2.25
1.70
0.59
-------
Treatment of Trickling Filter Effluent
The experiments on treatment of trickling filter effluent were conducted
in Pilot Plant No. 2, which was operated concurrently with Pilot Plant
No. 1. The system was placed in operation by filling the aeration tank
with filter effluent and 100 gallons of return activated sludge seed.
The trickling filter effluent was fed directly into the aeration tank
at a rate that was increased to 700 gpd by the end of the acclimation
period. This rate gave an average loading of 0.18 Ib BOD/lb MLSS.
Composite samples were collected and analyzed over an eight-day period.
The average loading rate was then increased to 0.54 lh BOD/lb MLSS.
After the system stabilized at the higher loading rate, composite sam-
les were collected for 13 additional days.
Results of the test runs A3 and M are also given in Table 4 and shown
in Figures 6 and 7. At the lower loading rate, the treatment effi-
ciency was excellent with an average effluent total BOD of 18 mg/1. The
soluble BOD was always below 15 mg/1 and averaged 6.0 mg/1. When the
loading was increased to 0.54 rb BOD/lb MLSS, the effluent quality
decreased markedly with an average soluble BOD of 33 mg/1 and a total
BOD of 83 mg/1. Removal rate constants for the soluble BOD were cal-
culated and are shown in Table 5.
The SVI at the 0.18 Ib BOD/lb MLSS loading rate fairly consistently
averaged 215. At the higher loading rate, however, the SVI varied
widely from 92 to 317. Once again, the data indicated increased dif-
ficulty in settling at the higher loading rates.
Treatment of Combined Wastes
Pilot Plant No. 2 was used for the experiments with a 1:1 mixture of
trickling filter effluent and settled domestic sewage. Following the
studies on trickling filter effluent, settled sewage was added to the
influent waste stream. The feed rate of each waste was set at 650 gpd
to produce a detention time of 7.7 hours and a loading rate of 0.32 Ib
BOD/lb MLSS. Composite samples of the two influent streams and the
secondary effluent were collected for nine days and the data summarized
as run A5 in Table 4 and shown in Figure 8.
During this test run, a styrofoam dome was placed over the roughing fil-
ter to control odors, and the effluent BOD increased significantly. The
average filter effluent BOD during the pilot plant test was 723 mg/1
with BOD concentrations greater than 1,000 mg/1 on two separate days.
The average total BOD in the pilot plant effluent was 35 mg/1, giving
a total BOD removal efficiency of approximately 92 percent. The sol-
uble BOD in the effluent remained below 10 mg/1, with the exception
of the last two days of operation when the filter effluent BOD in-
creased to over 1,000 mg/1. The results of this study indicated that a
mixture of settled sewage and brewery waste can be effectively treated
by the complete-mix process.
Of special note, the SVI during this experiment averaged 183, which is
considerably below the values recorded for brewery wastes alone. This
390
-------
Ol
FIGURE 6 BOD REDUCTION IN PILOT PLANT TREATING
TRICKLING FILTER EFFLUENT. LOADING
RATE - 0.18 lb/BOD/11) MLSS/day
391
-------
i,000
900 •
800
ui
€f>
10 II 12 13
TIME-DAYS
FIGURE 7 BOD REDUCTION IN PILOT PLANT TREATING
TRICKLING FILTER EFFLUENT. LOADING
RATE - 0.54 !b BOD/lb MLSS/day
392
-------
1000
CO
TIME-DAYS
FIGURE 8 BOD REDUCTION IN PILOT PLANT TREATING 1:1
RATIO SETTLED SEWAGE AND FILTER EFFLUENT
LOADING RATE - 0.32 Ib BOD/lb MLSS/day
393
-------
result Indicates improved settleaMlity for the combined wastes, perhaps
a significant factor in achieving good plant performance.
AeroMe Digestion of Sludge
The first test conducted on aerobic sludge digestion was in Pilot Plant
No. 1 on a semicontinuous feed basis. Initially, 30 gallons of primary
sludge and 150 gallons of waste activated sludge from Plant A were added
to the aeration basin. Every second day thereafter, 180 gallons of feed
were added to the tank with a corresponding removal of effluent. This
procedure resulted in a suspended solids concentration of approximately
1.0 percent with a 22-day hydraulic retention period. In an effort to
concentrate the sludge by raising the average influent BOD and suspend-
ed solids, the feed rate was changed to 70 gallons of primary sludge
and 120 gallons of waste activated sludge.
The volatile solids loading on the aerobic digester averaged 0,075 lb/
ft3/day over the testing period. Reductions achieved by the aerobic
digester were 36 percent in volatile solids and 40 percent in BOD. A
summary of the pilot plant performance during this test is presented
in Table 6. The data show performance comparable with published values
on aerobic digesters and indicate that this sludge may be successfully
treated aerobically.
A brief test was conducted on the digester effluent for possible odor
problems by drying six inches of digested sludge on a makeshift sandy
earth bed. The sludge dewatered very rapidly and left a dry residue
with no noticeable odor.
Researchers have recently attempted to correlate the degree of sludge
digestion with changes in sludge parameters such as pH, alkalinity, and
nitrate content. A batch study was initiated in Pilot Plant No. 2 with
70 gallons of primary sludge and 120 gallons of waste activated sludge.
Analyses were conducted on this sample during aeration to determine the
parameters against which the degree of sludge digestion could be mea-
sured. The data obtained from the experiment are presented in Figure 9.
It may be seen that for this single sludge sample, essentially all of
the BOD and volatile solids removal was completed by the sixteenth day
of operation. Correspondingly, the pH had dropped to 5.0 by the eigh-
teenth day of operation, and the total alkalinity was reduced from over
300 mg/1 to less than 50 mg/1 by the sixteenth day. Comparing these
results with alkalinity and pH data from the continuous feed test re-
veals that with a pH of 5.0 to 6.0 and alkalinities around 40 mg/1,
the continuous feed process accomplished essentially complete digestion
within a retention period of 21 days.
The indicated changes are explained by the fact that aerating a car-
bonate-bicarbonate water removes carbon dioxide and gradually lowers
the alkalinity. While the sludge is still actively digesting, carbon
dioxide is being returned to the water. A sharp drop in alkalinity,
therefore, does not occur until digestion is substantially slowed.
Furthermore, with the drop in buffering capacity of the liquid and the
conversion of organic and ammonium nitrogen to the nitrate form, acid-
ity increases and the pH drops to some new low level.
394
-------
vO
Ui
TABLE 6
AEROBIC SLUDGE DIGESTER PERFORMANCE
CONTINUOUS FEED**
Constituent Averages
Feed
Effluent
% Reduction
COD-mg/1
Total
20,193
10,240
49.0
BOD-mg/1
Total
5,678
3,207
43.5
Total
14,409
9,754
32.4
Solids- me/1
Suspended
13,262
7,869
40.6
I
Volatile jaH Alkalinity
12,434
7,894 6.1 32
36.7
Average DO
Uptake
me/l/hr
-
38
•~
*Feed added and effluent withdrawn every two days.
-------
n
1 1 1 1 1 1 1 —
- — r— 1 — i
PH
o c
— I 1 1
400
ALKALINITY as CaCo3
8 10 12 14
TIME-DAYS
FIGURE 9 BATCH DIGESTION OF BREWERY WASTE SLUDGE
396
-------
DISCUSSION
Based on the results of these pilot plant studies, design criteria for
a complete-mix activated sludge system to handle brewery wastes have
been established as follows:
1. Primary clarification, surface loading rate: 750 gpd/ft2
2. Aeration basin, loading rate; 0.25-0.30 Ib BOD/lb MLSS
(based on 2,500 mg/1 MLSS)
3. Secondary settling, surface loading rate: 400-500 gpd/ft2
Recommendations have been made and are being implemented to modify
Plant A in accordance with the pilot plant studies. The existing
aerobic digesters will be converted to activated sludge basins with
new sludge incineration facilities for sludge disposal. Because of
piping restraints, the initial plant modifications will create an acti-
vated sludge system more closely resembling step-feed. Total conver-
sion to a complete-mix pattern may be undertaken at a later date.
A relatively low organic loading rate appears essential if sludge bulk-
ing is to be controlled. The addition of domestic wastes appears to
improve sludge settleability significantly.
The use of a pure oxygen system may offer special advantages in con-
trolling sludge bulking. With a high strength brewery waste, it is
often difficult, if not impossible, to maintain satisfactory dissolved
oxygen levels throughout the aeration basin using conventional aeration
equipment. At low dissolved oxygen levels, 0.1-0.2 mg/1, Sphaerotilus-
type organisms compete very strongly and may give rise to sludge bulk-
ing. The use of pure oxygen in place of aeration is suggested as a
possible remedy for this situation.
CONCLUSIONS
The treatment of brewery wastes has proved difficult at numerous instal-
lations throughout the country. Two major difficulties, high organic
loadings and sludge bulking, are repeatedly encountered.
Activated sludge systems seem to offer the best approach for handling the
high soluble BOD wastes. Several Kraus modifications of the activated
sludge process are functioning reasonably well on brewery wastes without
appreciable bulking. Pilot plant studies reported herein indicate that
complete-mix activated sludge can perform equally well without bulking
if the loading rate is kept relatively low, i.e., about 0.3 Ib BOD/lb
MISS.
Plastic-media trickling filters have been used as roughing units at
several locations. Although the filters accomplish 45 to 60 percent BOD
removals, most of these units have given rise to objectionable odors
detectable outside 'the treatment plant property. Unless the odors can
be eliminated, roughing filters appear to have limited application for
brewery wastes.
397
-------
Finally, in-plant control of some of the major waste streams can vastly
improve the waste treatment plant operations. In particular, the collec-
tion and equalized discharge of press liquor and caustic and acid clean-
ing solutions will greatly reduce the treatment problems inherent with
"brewery wastes.
398
-------
LITERATURE CITED
1. Internal Revenue Service, Department of the Treasury. "Fiscal
year, 1970, alcohol and tobacco summary statistics." Publica-
tion 67 (3-71).
2. O'ROURKE, J. T., and TOMLINSON, H. D. "Extreme variations in
brewery waste characteristics and their effect on treatment."
Proceedings of the 17th Purdue Industrial Waste Conference,
Purdue University, May, 1962.
3. McWHORTER, T. R., and ZIELINSKI, R. J. "Waste treatment for the
Pabst Brewery at Perry, Georgia." Presented at the 26th Purdue
Industrial Waste Conference, May, 1971.
4. LEWIS, H. V. "Treatment of brewery waste at Adolph Coors Co.,
Golden, Colorado," unpublished paper.
5. ECKENFELDER, W. W. "Application of kinetics of activated sludge
to process design," Advances in Biological Waste Treatment,
Pergammon Press, 277 (1963).
399
-------
CATTLE PAUNCH CONTENTS AS FISH FEED
SUPPLEMENT: FEASIBILITY STUDIES
by
S. C. Yin and Jack L. Witherow*
SUMMARY
The seriousness of cattle paunch contents from abattoirs as a water pol-
lutant was pointed out. As a remedy, it was suggested that the material
be dried and used as a feed supplement in the rapidly growing commercial
channel catfish farming industry. Air drying and BOD of fresh paunch
were studied, as well as the frequency of occurrence of Salmonellae in
the material. An EPA grant project (12060 HVQ) at Oklahoma State Univer-
sity will study the feasibility of using dried paunch as a feed supple-
ment in both pond and cage cultures of channel catfish; the effects of
the two methods of culture and the possible deleterious effect of incor-
porating dried paunch in fish feed on water quality will also be
determined.
INTRODUCTION
Among abattoir wastes, the rumen or paunch contents of cattle rank high
as water pollutants. This material from the rumen, also known as paunch
or paunch manure, is simply the partially digested food which the animal
has ingested and stored in the first compartment of the stomach. Tech-
nically, therefore, this material cannot be considered as fecal material,
and the common name—paunch manure—is a misnomer, although from the
standpoint of appearance and odor, manure is indeed an appropriate name
for the substance.
High solids and high BOD are the characteristics which make paunch a
serious water pollutant. The paunch is handled wet or dry. In wet han-
dling, the contents are washed with large volumes of water. The larger
solid particles are usually screened out and disposed of in some manner
as solid wastes. However, studies done at the Robert S. Kerr Water Re-
search Center and elsewhere have shown that about 80 percent of the
BOD of paunch is water soluble. Thus, in this method of handling, about
80 percent of the BOD of paunch is found in the liquor that passes through
the screen, adding a tremendous load to the wastewater. In dry handling,
the contents are dumped dry and hauled off for disposal on land. Ideally,
the material is spread thinly on cultivated land and then immediately
covered with a layer of soil or tilled in with the soil, where the material
will slowly decompose, acting as a fertilizer and soil conditioner. In
this way, not only is water pollution eliminated, but fly breeding and
odor nuisance are also precluded. Unfortunately, this is rarely done. A
common practice is to openly dump the material into the nearest gully—
a practice which eliminates paunch from the wastewaters of the plant
*Environmental Protection Agency, Robert S. Kerr Water Research Center,
P. 0. Box 1198, Ada, Oklahoma 74820.
401
-------
and superficially appears to have taken care of this potential pollutant;
for, not only are these open dumps breeding sanctuaries for flies, but
any rainfall runoff will carry a substantial portion of the material into
the nearest water course.
Obviously, a solution to the problem is to seek ways, other than land dis-
posal, of beneficially utilizing the material. Since fresh paunch is a
malodorous slurry, it must first be dried for easier handling and to re-
move the objectionable odor. Baumann (1.2) described the use of a mechi-
cal heat dryer for drying paunch. Additionally, chemical analyses were
made on the dried product for various components. Table 1 shows the
results of these analyses.
Table 1. Analyses of Dehydrated Paunch*
Percent
Moisture
Protein
Fat
Carbohydrate**
Crude Fiber
Ash
Calcium
P^Oc
2 5
Mean
6.8
12.7
3.1
40.8
26.2
7.2
0.59
1.47
Std. Dev.
1.9
1.5
0.6
5.3
3.2
0.7
0.09
0.25
No. of Detm's.
96
88
86
44
88
88
60
60
(2).
*Taken from Baumann
**Calculated by subtracting total percentage of moisture, protein, fat,
crude fiber, and ash from 100 for each sample.
It is quite apparent that this waste material retains most of the nutri-
tional value contained in cattle feed. Aside from the unfounded objection
by some froa the aesthetic viewpoint, that it would be logical to refeed
the material to beef cattle requires no perspicaciousness. Indeed,
refeeding of paunch and even chicken manure and cattle manure to cattle
has been done successfully. One experiment in which dried paunch was
used at various substitution rates to replace ground shelled corn or
dehydrated alfalfa in rations for finishing cattle was described by
Goodrich and MeiskeO). TO increase usage and gain wider outlet for
402
-------
dehydrated paunch, it would be advantageous to seek additional species, of
animals for the recycling of the material. The channel catfish may be a
most suitable vehicle for the recycling of paunch because of the following
reasons:
1) Fish in general are more efficient in the conversion of feed into
edible flesh.
2) Catfish are known to be omnivorous.
3) Commercial catfish farming has been and continues to be a rapidly
growing industry in the U. S.
4) It has been documented that channel catfish will grow just as
rapidly when fed with a ration consisting of a 50-50 mixture of
41 percent protein-cotton seed cake and feedlot manure as when
fed with a ration consisting of 41 percent protein-cotton seed
cake and milo.(^)
Nutritional studies have shown that feed with a protein content of 28-32
percent will produce the fastest growing channel catfish (5,6). Dried
paunch, with a protein content of approximately 13 percent, will not
suffice as a complete feed in channel catfish production, but could well
be used as a feed supplement to replace some of the normally used con-
stituents such as soybean meal, alfalfa meal, and cottonseed meal. It
has been projected that commercial catfish production will reach 112.5
million pounds annually by 1975. Assuming a substitution rate of 25
percent dried paunch in commercial catfish feed, it is estimated that
45 percent of all the paunch produced by the meat industry in the country
could by utilized through this outlet by 1975.
The following preliminary feasibility studies were made to provide in-
formation as to whether the above-mentioned idea of using dried paunch
as a feed supplement in catfish culture merits further investigation.
AIR DRYING STUDIES
Although the project at Beefland International, Inc.(2) has demonstrated
that it is practical to dry paunch mechanically with a heated dehydrator,
the capital cost for the equipment can be prohibitive for the small meat-
packer. Consequently, it was decided to investigate the feasibility of
air drying the paunch. After placing the fresh paunch a 4-inch deep
layer in a plastic pan and exposing the pan to sun and air, it was found
that the surface dried rapidly, forming a crust, while underneath the
crust the moisture remained for days and the material soon became moldy.
By turning the material daily, the drying process was greatly accelerated
and mold development was prevented. If turned daily, a 4-inch deep layer
of paunch can be air dried within a week.
Subsequent experimentation was conducted on a larger scale by air drying
paunch in a specially built concrete bed on the grounds of a local meat-
packing plant. The overall measurements of the bed were 18 feet long by
9 feet wide, with an 8-inch high by 4-inch thick curb around the sides.
The bed was divided equally into three separate compartments. A
403
-------
corrugated iron roof with a 4-foot overhang on all sides was erected over
the bed to keep out rain water. Fresh paunch from the plant was spread
on the bed to a depth of approximately four inches. The plan was to mix
and turn over the material manually with a garden rake each day. The
owner of the plant agreed to assign one of his employees to perform this
task. However, this work amounted to an additional unpleasant chore to
this employee and the assignment was not religiously carried out. The
project's objective was to demonstrate that paunch can be air dried within
a reasonable period in all seasons of the year under various kinds of
weather conditions, but because of the above-mentioned flaw in this part
of the work the results obtained were inconclusive. Moreover, the 4-foot
overhang in the roof proved to be inadequate in keeping out rain water,
and this prolonged the drying period in several instances. Nevertheless,
four batches of paunch have been dried successfully; their moisture con-
tent after reaching equilibrium with the atmosphere ranged from 16 to 20
percent. The dried material was bagged in burlap feed sacks and stored
in an open shed. The first batch has been stored in this manner for nine
months with no evident signs of spoilage.
BIOCHEMICAL OXYGEN DEMAND STUDIES
Analysis of fresh paunch in the laboratory showed that after four weeks
the material has a BOD of approximately 100,000 milligrams per 1,000
grams. Obviously, if dried paunch still exerts as much oxygen demand as
the fresh material, its incorporation into catfish feed could be a matter
of concern, since any of the uneaten feed would become a serious water
pollutant. Accordingly, BOD tests were done on samples of air dried
paunch. The results are shown in Figure 1. After 76 days, Sample 1
showed an oxygen uptake of 183,000 milligrams per 1,000 grams, with no
indication of nitrification occurring until the 89th day. The oxygen
uptake of Sample 2 was monitored for up to 131 days, with no sign of
nitrification. The oxygen uptake after 131 days was 366,000 milligrams
per 1,000 grains. The oxygen uptake for Sample 3 after 71 days was
258,000 milligrams per 1,000 grams. Again, there was no evidence of
nitrification at the end of this period.
Clearly, the dried material has such an extended ultimate oxygen demand
that a 5-day BOD of this organic material does not give a true picture
of the extent of the problem created when the material is released and
allowed to remain in a body of water. If an appreciable amount of the
feed containing paunch remains uneaten, a serious water pollution pro-
blem could result, with consequent detriment to the fish due to oxygen
depletion. In considering the use of paunch as a fish feed supplement,
this important point definitely should not be overlooked.
SALMONELLA STUDIES
Decker and Steele(^) considered salmonellosis as one of the most important
zoonoses transmitted by animal wastes. Hence, an attempt was made to
determine the frequency of occurrence of Salmonellae in paunch freshly
removed from the rumen of cattle slaughtered at a meat-packing plant.
The fluorescent antibody (FA) technique as described by Fantasia (8) was
compared with the conventional culture procedure.
404
-------
zoopoo -
180000 -
10 20
30
40 50
DAYS
60 70 80 90
FIGURE I-BOD OF DRIED PAUNCH
405
-------
In the culture procedure, 25 grams of the freshly collected paunch was
placed in 225 milliliters of Lactose Broth (Difco) for pre-enrichment.
After incubation at 37°C for 18 to 24 hours, 1 milliliter of the pre-
enrichment culture was inoculated into a tube containing 10 milliliters
of Selenite-Cystine Broth (Difco), followed by incubation at 37°C for
24 hours. This selective enrichment culture was then streaked on plates
of SS Agar (Difco), Brilliant Green Agar (Difco), and Bismuth Sulfite
Agar (Difco). After 24 hours' incubation at 37°C, the plates were
examined for typical and suspected colonies of Salmonella. A strain of
Salmonella typhimurium originally obtained from NCDC was used as a
control.
A total of twelve paunch samples has been tested, with negative results.
Because no Salmonella was isolated by the culture procedure, the FA
method was abandoned, since any positive results obtained in this
relatively new and experimental method would have had to be confirmed
by the conventional culture procedure.
CATFISH STUDIES
An important factor in the determination of whether dried paunch is
suitable as a feed supplement for channel catfish is the palatability
of the material to the fish. Twelve channel catfish averaging about
half a pound each were placed in laboratory tanks. After the fish were
conditioned to the environment and to feeding on commercial floating cat-
fish pellets, chunks of air-dried paunch were thrown into the tanks. The
chunks floated on contact with the water, and it was observed that the
fish readily consumed the material. It was concluded that dried paunch
is acceptable to channel catfish as a food.
A full-scale experiment has been initiated at Oklahoma State University
under an EPA grant. The project is designated Project No. 12060 HVQ and
is under the direction of Dr. Robert C. Summerfelt and Dr. Austin K.
Andrews, both at OSU. Open pond and cage cultures of channel catfish
will be used to evaluate feeds containing several substitution levels of
dried paunch. The feeds are specially formulated so that they will be
isonitrogenous and isocaloric. This project represents a cooperative
effort between OSU and EPA's Robert S. Kerr Water Research Center,
since the latter will be mainly responsbile for the water quality studies
of the ponds to determine the effects of the two different methods of
catfish culture on water quality, and to evaluate the possible detrimental
effects of paunch in fish feed on water quality.
DISCUSSION
These brief, preliminary studies have shown that it is feasible to use
dried paunch as a feed supplement in catfish culture. Although, due to
circumstances beyond control, inconclusive data with regard to actual
time requirements were obtained on air drying, it was demonstrated that
paunch can be air dried successfully, and the dehydrated product can be
stored for months without spoilage. A mechanical device of some sort,
perhaps a flail mower, to turn the paunch over regularly, would hasten
the drying process, prevent the development of molds, and make it
economically attractive for the small meat-packer. It appears unfeasible
406
-------
to keep flies from ovipositing on the paunch, but perhaps accelerating
the drying process by daily turning will prevent the development of fly
larvae and the subsequent pupae from emerging, thus, keeping the paunch
drying bed from being a fly breeding ground(9).
Conceivably, dried paunch incorporated into fish feed could become a
serious water pollutant if the feed remains in the water for a long
period, due to the high ultimate BOD of the material. However, in fish
culture the amount of feed given each day is based on a certain percen-
tage (usually 2-3 percent) of the body weight of the fish for the most
efficient growth. Presumably, all the feed given at each feeding is
consumed by the fish within a short period. This is especially prob-
able in pond culture, in which case the water polluting potential of
dried paunch is of lessened concern. In suspended cage culture, the
situation is somewhat different. Here, even though the feed used is of
the floating type, the pellets will eventually sink after being placed
in water, and once the pellets drift out of the confines of the cage the
fish will not be able to retrieve them. When that happens, the dried
paunch in the feed will definitely pollute the water, depleting the
dissolved oxygen to the detriment of the fish. Studies done in the
grant project will provide an answer as to whether this will be a
problem.
No Salmonellae were isolated from the fresh paunch, which was somewhat
unexpected. The absence of Salmonellae is likely due to the low pH
of paunch, some samples of which have been found to have a pH as low
as 5.6. Moreover, during the pre-enrichment culture in lactose broth,
further fermentation occurs, the organic acids produced bringing the pH
of the mixture after 24 hours' incubation to approximately 4.9 Because
of the low pH, the material may be safe from contamination by pathogenic
bacteria; however, this must be verified. It is still possible that
successful isolation of Salmonellae can be accomplished when a more
sensitive isolation method such as that described by Kenner, Dotson and
Smith(10) is used. Further studies in this area are indicated.
The palatability of dried paunch to channel catfish will not surprise
any catfish fisherman, who uses such baits as stink baits and chicken
entrails to lure these fish. The catfish studies to be conducted at
Oklahoma State University are expected to produce reliable and con-
clusive information on whether dried paunch is suitable as a feed supple-
ment in channel catfish culture. If favorable results are obtained, it
should bring about a demand for dried paunch in the rapidly expanding
catfish farming industry, thereby converting this material from a
troublesome waste which is a potentially serious water pollutant into a
useful by-product which will help another industry to provide a tasty
and nutritious food for mankind.
407
-------
LITERATURE CITED
1. BAUMANN, D. J. 1971. Dehydration of Cattle Rumen and Whole Blood.
Proc. Second Nat. Symp. on Food Processing Wastes, Denver, Colorado,
March 23-26, 1971, pp. 313-322.
2. BAUMANN, D. J. 1971. Elimination of Water Pollution by Packinghouse
Animal Paunch and Blood. EPA, Water Pollution Control Research
Series, No. 12060FDS-11/71.
3. GOODRICH, R. D. and J. C. Meiske. 1969. The Value of Dried Rumen
Contents as a Ration Ingredient for Finishing Steers. University
of Minnesota, Department of Animal Science, 1969 Research Report B-124.
4. DURHAM, R. M., G. W. THOMAS, R. C. ALBIN, L. G. HOWE, S. E. CURL, and
T. W. BOX. 1966. Copraphagy and Use of Animal Waste in Livestock
Feeds, pp. 112-114. In Proc. Nat. Symp. on Animal Waste Management,
May 5-7, 1966, ASAE Pub. No. SP-0366.
5. LOVELL, R. T. 1969. Nutrition in Commerical Catfish Culture.
Presented at the 99th Meeting of the American Fisheries Society,
New Orleans, Louisiana, Sept. 10-13, 1969.
6. GRIZZELL, R. A., JR., 0. W. DILLION, JR., and E. G. SULLIVAN. 1969.
Catfish Farming. A New Farm Crop. U.S. Dept. of Agriculture,
Farmers' Bulletion No. 2244.
7. DECKER, W. M., and J. H. STEELE. 1966. Health Aspects and Vector
Control Associated with Animal Wastes, pp. 18-20. In Proc. Nat.
Symp. on Animal Waste Management, May 5-7, 1966. ASAE Pub. No.
SP-0366.
8. FANTASIA, L. D. 1969. Accelerated Immunofluorescence Procedure
for the Detection of Salmonella in Foods and Animal By-Products.
Appl. Microbiol. 18:708-713.
9. EASTWOOD, R. E., J. M. KADA, R. B. SCHOENBURG, and H. W. BRYDON.
1967. Investigations on Fly Control by Composting Poultry Manures.
J. Econ. Entomol. 60:88-98.
10. KENNER, B. A., G. K. DOTSON, and J. E. SMITH. 1971. Simultaneous
Quantitation of Salmonella species and Pseudomona aeruginosa.
Internal Report, Environmental Protection Agency, National Environmental
Research Center, Cincinnati, Ohio.
408
-------
CHARACTERIZATION OF FRUIT AWD VEGETABLE
PROCESSING WASTEWATERS*
M. R. Soderquist**, G. I. Blanton, Jr.** and D. W. Taylor***
INTRODUCTION
For the past two years, the Department of Food Science and Technology at
Oregon State University has been monitoring the wastewaters from Willamette
Valley fruit and vegetable processing plants. The data generated in the
study are being used to augment existing knowledge of the volumes and
characteristics of food processing effluents.
The need for such a study became evident when a state-wide processor survey
and concurrent literature review indicated that although considerable
information on fruit and vegetable processing waste streams was available,
most of the data were either so general as to be of limited use or had
been gathered in such a manner that reliance on them would be ill-advised.
For example, many of the studies were conducted 20 to 30 years ago using
"grab" samples gathered over short periods of time ranging from a few hours
to a few days. Data gathered in this manner are of dubious validity,
especially when one is dealing with food processing, where effluent strengths
and flows often fluctuate wildly.
To indicate the reliance on historical rather than contemporary data,
Table 1 was prepared. This table lists, for each of three commodities,
the wastewater characteristics cited by four respected text and reference
books dating from 1953 to 1971.
*This investigation was supported, in part, by funds from the Office of
Water Resources Research, U.S. Department of the Interior, under the
Water Resources Research Act of 196U, PL 88-379> and by the Oregon
Agricultural Experiment Station, the Oregon State University Graduate
School General Research Fund, and the Oregon State University
Computer Center.
**Department of Food Science and Technology, Oregon State University,
Corvallis, Oregon.
***National Environmental Research Center, Environmental Protection Agency,
Corvallis, Oregon.
Oregon Agricultural Experiment Station Technical Paper No. __338_8
409
-------
Table 1. Literature Values for End-of-pipe Wastewater Characteristics
Reference
Volume
(gal/case)
BOD
Whole kernel corn:
Rudolfs (1) 25-70
Gurnham (2) 25-70
Lund (3) 25-70
Nemerow (U) 25-70
Red beets:
Rudolfs (1) 27-65
Gurnham (2) 27-70
Lund (3) 27-70
Nemerow (U) 27-65
Green and wax beans:
Rudolfs (1) 26-1*1*
Gurnham (2) 26-1*1*
Lund (3) 26-1*1*
Hemerow (M 26-1*1*
n23-6025
1120-6300
1120-6300
1123-6025
1580-5^80
1580-7600
1580-7600
1580-51*80
160-600
160-600
160-600
160-600
Suspended Solids
(ntt/1)
300-1*000
300-1*000
300-UOOO
300-UOOO
71*0-2188
71*0-2220
71*0-2220
720-2188
60-85
60-150
60-150
60-85
While some minor variations in values are evident, the similarities are
unmistakable. All but one of these references cited the same source
of information, N. H. Sanborn (1*), who was associated with the National
Canners Association at the time he did that work. The remaining
reference was Gurnham (2), in which the chapter on "Canned Foods" was
authored by W. A. Mercer, also of the National Canners Association.
The fact that the values of Table 1 have remained essentially
unchanged for nearly twenty years might be explained in at least two
ways: l) the numbers have remained valid and are applicable to today's
processing plants; or 2) they have become out-dated, but nonetheless,
have been transferred from publication to publication, apparently
without adequate verification.
Sanborn was the author of the chapter on food processing in the early
(1953) book edited by Rudolfs (l). The sources of Sanborn's values
were not individually identified, but if it is assumed that they were
included in his bibliography, where the publication dates varied from
1913 to 19U8, perhaps it would be fair to say that the average
wastewater characteristic in Sanborn's chapter was generated around 19l*0.
Specifics regarding methods and frequency of sampling and analysis were
often unavailable to Sanborn; indeed he stated (l):
-------
"Details concerning the collection of samples are frequently
lacking. It is believed that most, if not all, of the data
were obtained after screening."
Data origins are difficult to pinpoint, but if the findings of this
exercise are typical, many of the currently-used food processing
waste-water characterization figures (because of their antiquity and
questionable circumstances under which they were generated) may
not warrant the confidence of those who rely on them. Thus, the need
for contemporary wastewater quantity and quality analyses was recognized
by the authors. This need was underscored in a recent publication on
"Research Needs in Sanitary Engineering" (5) by the Sanitary Engineering
Research Committee of the American Society of Civil Engineers:
"Industrial wastes are typically less well identified [than
sanitary sewage]... All of these waste streams must be more
completely characterized to insure optimum environmental
control by focusing attention on the most significant
problem areas."
THE FIRST SEASON
In 1970 the authors began the task of supplementing and verifying (or
refuting) existing data by developing wastewater quantity and quality
profiles for each of Oregon's major commodity-process combinations.
Analyses were conducted as prescribed by Standard Methods (9) except
phosphorus determinations, where the methods of Jankovic, e£ al. (10) were
followed. All samples were screened (20 mesh) prior to analysis. Since
a newly-constructed (and untested) mobile laboratory (6) was to be employed,
a processing plant in close proximity to the O.S.U. campus was chosen.
This would minimize the inconvenience of altering, repairing and "debugging"
the new laboratory. Hindsight reveals that this criterion should have been
assigned a lower priority than some others, most notably plant layout. It
soon became apparent that the plant's physical configuration presented
difficult problems to the wastewater sampling technician. In many cases the
collection of discrete samples from single commodity unit-operations was
impossible; in those instances, samples containing wastewaters from the
simultaneous processing of more than one commodity were taken.
Since this paper is limited to the presentation of data from the
processing of single commodities, not many of the results of the first
season's efforts are included. Consequently, because of the small
numbers of datum points involved, statistical analyses of these results
have not been attempted.
Corn
The plant processed several commodities, including sweet corn, beets,
green beans, purple plums and red sour cherries, but only corn and
beets were processed discretely.
The corn was husked, trimmed, washed, cut from the cob, de-silked, and
washed again. Then it was canned (whole-kernel) and retorted. A total
of nine days' "corn-only" processing yielded the data of Table 2.
'411
-------
Table 2. Total Plant Effluent Characteristics During Corn Processing
Parameter Mean Range
Flow (gpm) 207.5 121.9-317.8
(gpT) 1307 813-2002
(gal/case) 1*0.8 25.^-62.6
COD (lb/1Qn) 3^.38 32.99-35.89
In this table, flow was expressed in terms of gallons per standard
case (2U number 303 equivalent cans) by using the yield value found in
the latest "Yearbook" issue of Canner-Packer magazine (7). The range
of water usage expressed in that manner compares well with its
counterparts in Table 1, indicating that the published water usage
figures for whole-kernel corn processing were applicable to this
processing plant in 1970.
When considering wastewater constituents expressed in terms of
concentration (e.g., mg/1 or ppm) one should avoid direct comparisons
among plants or even among different processing periods within the
same plant. The reasons for this are many; one of the most obvious
IB the influence of production on waste load. In most processing
operations water usage is not proportional to product throughput.
The flow through each unit is either constant or increases from a
significant (non-zero) base level as some (often non-linear) function
of production. Therefore it is preferable to express wastewater
constituents in terms of production, as is COD in Table 2.
Comparison of the COD values of Table 2 with the BOD values of Table 1
is difficult because Table 1 lists concentrations. One can convert
the BOD values of Table 1 to equivalent COD's using the BOD:COD ratio,
0.75, found to be applicable in this study to combined (end-of-pipe)
corn waste. Subsequent conversion to a production basis, however,
becomes more difficult to defend. It is common knowledge that in a
waste stream, pollutant concentration more nearly approximates an
inverse function of water usage than a direct one. Both functions,
however, are poor estimates of reality. In Table 3 the data of Table 1
have been manipulated variously to illustrate the problems discussed
above. In the first two lines are expressed the two ranges of BOD listed
in Table 1, that of Rudolfs (l) and Nemerow (M being designated (a)
and that of Gurnham (2) and Lund (3), (b). In the next pair of lines
BOD has been converted to COD using the BOD/COD ratio (0.75). The
next two lines list COD's based on production under the (admittedly
unrealistic) assumption labeled "Case I": that the lowest concentrations
occurred at periods of minimum flow and the highest concentrations at
peak flow. Although this assumption is unreasonable, it sometimes
412
-------
Table 3. Literature Corn Waste Organic Values Expressed by Alternative
Methods
Parameter fiange Median
BOD (mg/1) (a) 1123-6025 357^
(b) 1120-6300 3710
COD (mg/1) (a) 1U98-803** 1*765
(b) 1U93-8UOO 1*9^7
Case I*: COD (ib/T) (a) 9.98-150.02 80.00
(b) 9.96-156.87 83.te
Case II**: COD (lb/T) (a) 27.97-53.58 U0.78
(b) 27.89-56.02 Ul.96
'Minimum concentration occurs at minimum flow and maximum at maximum
flow
**Minimum concentration occurs at maximum flow and maximum at minimum
flow
appears in the literature. Case II, then, lists the "opposite"
assumption (which, although more nearly correct, is also inaccurate):
that low concentrations coincide with peak flows and peak concentrations,
with low flows.
Based on Case II, then, the COD values of Table 2 do fall well within
the ranges derived from the values reported in the literature (Table 3).
Beets
Red beet processing at this plant involved washing, peeling, blanching,
slicing (or dicing), canning and retorting. The initial wash water
was heavily laden with suspended solids; four to five percent of the
incoming raw product weight was attributable to soil, most of which
was removed in the initial washing.
As with corn, nine days' "beets only" processing led to the flow data
of Table U. Using a yield of 70 standard cases per raw product ton (7)',
the flows expressed on a case basis were calculated. Comparing these
flows with their counterparts in Table 1 reveals the mean from the
current work to fall completely below the ranges quoted in the earlier
literature. In fact, the upper, end of the current range barely falls
within the lower range of the earlier literature values.
During beet processing only two 2U-hour flow proportioned "beets only"
samples were analyzed for chemical oxygen demand. The results of those
analyses also are listed in Table ^. As with corn, to facilitate
comparing these current values with those of the older literature,
413
-------
Table 5 was prepared similarly to Table 3.
Table U. Total Plant Effluent Characteristics During Beet Processing
Parameter Mean Range
Flow (gpm) 292.8 2149.8-353.5
(gpT) 1655 lUlO-1998
(gal/case) 2U.8 21.1-29.9
COD (lb/Ton) 7**.8 68.0-81.7
Table 5. Literature Beet Waste Values Expressed by Alternate Methods
Parawter Range Median
BOD (mg/1) (a) 1580-5^80 3530
(b) 1580-7600 U590
COD* (mg/1) (a) l8l6-6299 ^058
(b) 1816-8736 5276
Case !•«: COD (lb/T) (a) 28.61-238.91* 133.78
(b) 28.61-356.88 192.75
Case II«»: COD (lb/T) (a) 68.89-99.25 8U.07
(b) 75.00-137.65 106.33
•BOD/COD =0.87
«*See footnotes for Table 3.
Based on Case II, the COD values of Table U fall on the lower part
of the range of values expressed in the older literature.
Tables 6 and 7 offer a comprehensive breakdown of the wastewaters
from the two isolable unit operations within the beet canning process:
raw product washing and blanching-peeling. Eight flow-proportioned
composite samples were analyzed in each case. In this plant the washing
process contributed 17 percent of the flow, containing only 2 percent
of the COD. Therefore it would little behoove the processor to
attempt reduction of his overall organic loading by modifying the
washing operation. The blanching-peeling process, however, was another
matter, where 39 percent of the total plant outflow contained85 percent
of the COD. This operation, then, would be a logical starting point
for effective overall organics reduction.
414
-------
Table 6. Beet Wash Effluent Characteristics
Parameter
Flov (gpm)
(gpT)
(gal/case)
COD (Ib/Ton)
Total phosphorus (ib/Ton)
Total inorganic phosphorus (ib/Ton)
Orthophosphate (ib P/Ton)
Ammonia (ib N/T)
Organic nitrogen (ib/T)
*constant flow
Mean
50.0*
281.2
U.O
1.7
0.033
0.020
O.OOU
0.002
0.010
2l6.1i-U21.U
3.1-6.0
0.1-7.9
0.012-O.OU9
0.007-0.033
0.002-0.008
. 0-0.003
0-0.028
Table 7. Beet Blanching and Peeling Effluent Characteristics
Parameter
Flow (gpm)
(gpT)
(gal/case)
COD (Ib/Ton)
Total phosphorus (ib/Ton)
Orthophosphate (ib P/Ton)
Ammonia (ib N/Ton)
Organic nitrogen (ib/Ton)
*constant flow
Mean
rU.6*
659.1»
9-U
63.5
0.156
0.139
0.091
O.lUU
0.075
U95.9-1339.7
7-1-19.1
U5.6-10U.7
0.118-0.203
0.116-0.151*
0.069-0.120
0.023-0.259
0.0114-0.151
Relatively little phosphorus and nitrogen were contributed to the plant
effluent by these unit operations. Washing produced 0.033 Ib P/ton raw
product and 0.012 Ib Kjeldahl N/toni whereas blanching and peeling contributed
0.156 Ib P/ton and 0.219 Ib K-N/ton. With a BOD/COD relationship of
0.87, the BOD:N:P ratio for washing becomes approximately U5:O.U:1. Likewise,
the ratio for blanching-peeling becomes
For satisfactory biological treatment, a minimal ratio is said to be
around 150:5:1 (8). This indicates that, if necessary, the wash water could
be treated biologically with only nitrogen addition, whereas the blancher-
peeler waste stream would require singificant nitrogen and phosphorus
415
-------
addition prior to treatment.
With both corn and beets the COD measured per ton of product was lower in
the present study than in the literature. This can be attributed in
large part to the reduced water usage (per ton of product) in today's
canneries when compared with those of twenty years ago. Water use
reduction generally reduces product-water contact time and thereby
reduces leaching.
THE SECOND SEASON
During the 1971 processing season the mobile laboratory was located at a
large processing plant where the processing lines for the various
commodities were distinct and well separated. This facilitated the
collection of representative samples from each major unit operation
without risk of interference from other commodities.
The processes monitored included the canning of Lambert and Royal
Anne cherries, green beans and Bartlett pears. In most cases, sufficient
numbers of samples were collected to permit statistical analyses of the
analytical results. These analyses resulted in means, ranges and
standard deviations for sixteen different parameters, each of which
was expressed (where appropriate) both as a concentration and on a
raw product tonnage basis.
Green Beans
As shown on Figure 1, the green bean canning process involved an initial
washing followed by grading, snipping of ends (in Chisholm Ryder*
snippers), cutting, blanching (in rotary water blanchers), canning and
retorting. A subsequent paper will review the complete results of the
green bean characterization; emphasis here is placed on the end-of-
pipe effluent plus the major contributors to the total pollution load:
the washing and grading and the blanching processes.
Table 8 presents the characteristics of the total process effluent.
Standard deviations are not listed on this table because it represents a
summation of the means, maxima and minima from the sub-processes.
It is interesting that the per case flows fell completely below the range
quoted in the earlier literature (Table l) supporting the theory that
present-day canneries are more conservative in their water consumption
practices than in the 19^0's.
When the BOD values of Table 1 are expressed in terms of raw product
tonnage (assuming a Case II function) .they become: 7.31* to 16.25 Ib/T.
The BOD values of Table 8 fall below that range, leading to the same
conclusion mentioned earlier with respect to corn and beets.
-*Note Disclaimer at end of paper.
416
-------
RAW
PRODUCT
WASHING
I
[ GRADING
SNIPPING
CUTTING
I
BLANCHING
1
CANNING
COOKING
FINISHED
PRODUCT
Figure 1. Snap.Bean Processing
417
-------
Table 8. Total Plant Effluent Characteristics During Green Bean
Processing (19 samples).
Parameter
Flow (gpm)
(gpT)
(gal/case)*
COD (ib/T)
BOD/COD
BOD** (ib/T)
Total Solids (lb/T)
Suspended Solids (lb/T)
Settleable Solids (ml/I)
Total Nitrogen*** (lb/T)
NO" (ib-N/T)
NO' (Ib-N/T)
NH. (Ib-N/T)
Organic N (lb/T)
Total Phosphorus (lb/T)
Ortho-POT (ib-P/T)
Inorganic P (lb/T)
Total. Soluble P (lb/T)
PH
Dissolved Oxygen (mg/l)
Temperature (°C)
Mean
0.0065
0.210
0.0^*30
0.0218
0.0297
0.0356
6.1
7.9
28.0
685-92U
2163-2916
17.30-23.33
1*.93-10.36
2.61-5.U9
7.13-13.82
1.57-U.55
0.1-5.0
0.161*9-0.2966
0.0033-0.0110
0.0026-0.0136
0.159-0.272
0.0288-0.0562
0.0136-0.0299
0.0215-O.OU33
0.0203-0.0 UU3
5.1-7.1
6.5-8.U
25.8-31.3
•Calculated on a yield basis of 125 cases/ton (7).
•"Calculated from COD by using BOD/COD ratio.
•••Calculated by summing components.
From Table 8 the BOD:N:P ratio of 8U:5:1 can be calculated. Remembering
the (nutrient) minimum ratio to be 150:5:1, the bean processing waste
appears not to be nutrient deficient from the standpoint of biological
waste treatment. It should be noted, however, that only 6.2 percent of
the nitrogen was in the more assimilable inorganic form (2.9 percent
ammonia), whereas 83 percent of the phosphorus was in the more-readily-
utilized soluble form.
The volatile (combustible* content of the total solids in the combined
effluent was 73 percent. In terms of total solids and suspended solids,
the unit operation having the greatest impact on the overall waste
load was the washing-grading process, as shown in Table 9. For
example, 77 percent of the total bean process suspended solids load was
contributed in this step. The low volatile solids content (38 percent)
and a visual inspection of the solids substantiated the conclusion
418
-------
that this was primarily soil, which had "been transported with the beans
from the field. The washing-grading sub-process also contributed large
volumes of vastevater (20.9 percent of the total) to the system., being
second only to clean-up (32.6 percent of the total) and retorting
(29.0 percent).
Table 9- Green Bean Washing and Grading Process Effluent Characteristics
Parameter
Flow (gpm)
(gpT)
(gal/case)*
COD (ib/T)
BOD** (Ib/T)
Total Solids (ib/T)
Settleable Solids (ml/l)
Suspended Solids (lb/T)
Total Nitrogen*** (lb/T)
NO 3 (ib-H/T)
Mean
16U
519
U.15
1.27
0.67
3.09
l».5
2.07
0.0561*
O.OOlU
Std.
Range Deviation
1148-191 23.3
U67-S03 73.5
3.7^.82
0.7^-1. 89 0.58
0.39-1-00
2.23-U.68 1.38
3.0-7-0 1.3
1.25-3-57 1.31
O.OU58-0.0650 —
0.0008-0.0020 0.0008
% of
Total
__
20.9
18.6
—
32.0
77.0
25,2
19.2
UOg (ib-N/T) 0.0000
NK3 (lb-N/T) 0.0000
Organic N (lb/T) 0.0550
Total Phosphorus (lb/T) 0.0120
Ortho-Pij (ib-P/T) 0.0038
Inorganic P (lb/T) 0.0076
Total Soluble P (lb/T) 0.0079
pH 7.1
Dissolved Oxygen (mg/l) 9.7
Temperature (°C) 17.7
0.01*50-0.0630 0.0090
0.0090-0.0160 0.0050
a 0.0005
0.0030
O.OOU5
0.6U
1.37
0.00514-0.0097
O.OOU7-0.0111
6.8-7.5
8.U-10.U
1U.8-20.3
0.0
26.2
27.9
17.1+
25.6
22.2
Calculated on a yield basis of 125 cases/ton (7).
** Calculated from COD using BOD/COD = 0.53.
*** Calculated by summing components.
As was expected, the greatest contributor to the plant wastewater system in
terms of COD, nitrogen and phosphorus was the blanching operation, which
is characterized in Table 10. The rotary water blanchers generated kk percent
of the total process COD (hence, BOD) in this instance. The total solids
level was comparable to the previous unit operation, but volatile solids
increased from 73 to 79 percent. The blanchers were the major sources
of nitrogen and phosphorus, producing, for exajnple, 63 percent of the
ammonia and U3 percent of the orthophosphate found in the combined wastewater
stream. The 30D:N:P ratio.for this sub-process was 109:6:1. 93 percent
419
-------
of the total nitrogen was in the organic form vhereas 89 percent of the
total phosphorus was in the soluble form.
Table 10. Green Bean Water Blanching Effluent Characteristics* ( 7 samples)
Parameter
Flow (firpm)
-------
Cherries
Two different varieties of sweet cherry, Royal Anne and Lambert, were
processed at this plant. A comparison of Figures 2 and 3 reveals that
the processing methods were similar with one exception: stemmers
(Atlas Pacific) were used with the Royal Annes, whereas none were needed
for the Lambert cherries which were received stemless. The similarity of
processing methods permitted investigation of varietal and ripeness
influences on wastewater composition. The results were impressive;
markedly different wastewater streams resulted.
/
Royal AnneJ?herries: As shown on Table 11, the canning of Royal
Anne cherries required 1510 gallons of water per ton of raw product.
This 1510 gallons contained organics which would exert about 28 Ibs
COD; they also contained about 27 Ibs total solids (of which about
80 percent was volatile). The solids were largely soluble or colloidal,
indicating that further screening (beyond the 20 mesh screening that
all samples received prior to analysis) would be useless.
Compared to snap beans, then, Royal Anne cherries contributed (on a
production basis) more than four times the COD (hence, BOD) and nearly
three times the solids, while requiring only about 60 percent of the
process water volume per ton of raw product.
When considering the unit operations within the Royal Anne canning
line, one notes that in nearly every category the major contributors
to the wastewater loads were the Dunkley pitters. When Table 12 is
compared with Table 11, these units appear to have contributed more
than 90 percent of every contaminant except phosphorus. However,
although the pitters were certainly the greatest source of all
wastewater constituents, it should be noted that only 1? percent of
the total Royal Anne cherry throughput was pitted. This means that
the total plant effluent, representing the results of production
throughout the season, cannot be directly compared with the pitter
effluent. Nevertheless, it seems a valid conclusion that the pitter
effluent (volatile solids = 96 percent) might best be handled by
segregation and separate treatment and/or by-product recovery.
The only unit operation not common to both the Royal Anne and the
Lambert cherry processing lines was stemming. The Royal Annes were
handled in Atlas Pacific stemmers. These units were the second-
highest water users in the process line (the first being the continuous
cookers). This water usage was about 570 gallons per ton of fruit
processed. Investigation of Table 13 indicates the contribution of
all contaminants from the stemmers, however, to have been minor. The
volatile solids level was 7^ percent.
Lambert Cherries; Varietal differences and/or degree of ripeness
(hence juice volume) were detectable between the Lambert and Royal Anne
cherries in that these differences were reflected strongly in the wastewater
characteristics. Table lU presents the data from the Lambert process.
Although the water usage was only two-thirds that of the Royal Annes' ,
the COD contribution was up 30 percent and the total solids, 35 percent
421
-------
ro
RAW
PRODUCT
1
BLOWER
1
STEMMING
1
GRADING
CANNING
1
COOKING
RAW
PRODUCT
BLOWER
GRADING
PITTING
PITTING
CANNING
COOKING
FINISHED
PRODUCT
Figure 2. Royal Anne Cherry Processing
Figure 3. Lambert Cherry Processing
-------
Table 11. Toted Plant Effluent Characteristics During Royal Anne
Cherry Processing (7 samples).
Parameter
Flow (gpm)
(gpT)
(gal/case)*
COD (lb/T)
BOD** (lb/T)
Total Solids (lb/T)
Suspended Solids (lb/T)
Settleable Solids (ml/1)
Total Nitrogen*** (lb/T)
NO" (ib-N/T)
N0~ (Ib-N/T)
NH (Ib-N/T)
Organic N (lb/T)
Total Phosphorus (lb/T)
Ortho-P0£ (ib-P/T)
Inorganic P (lb/T)
Total Soluble P (lb/T)
pH
Dissolved Oxygen**** (mg/l)
Temperature (°C) (excluding cookers)
(including cookers)
Mean
251.6
1510
13.85
27. T3
15.53
27.17
0.87
1.5
0.1631
0.0081
0.0000
O.OU93
0.1057
0.0388
0.0152
0.0153
0.0225
6.2
8.U
25.3
32.8
Range
166.6-319.2
1000-1955
9. 17-17. 91*
19.95-3U.65
11. 17-19. to
20.87-33.99
0.15-1.59
O.U-3.5
0.0912-0.2818
0.0031-0.0159
0.0032-0.1391*
0.081i9-0.1265
0.0l80-0.0660
0.0080-0.0279
0.0077-0.0276
0.0133-0.0325
5.6-6.9
7.7-8.8
22.0-26.0
29.0-3U.8
•Calculated on a yield basis of 109 cases/ton (7); 17$ of throughput
vas pitted.
**Calculated from COD by using BOD/COD ratio of 0.56.
***Calculated by summing components.
****Excluding cooker flow, where D.O. was 0 mg/l.
423
-------
Table 12. Royal Anne Cherry (Dunkley) Fitter Effluent Characteristics
Parameter
Flow (gpm)
(gpT)
(gal/case)**
COD (lb/T)
BOD*»» (lb/T)
Total Solids (lb/T)
Suspended Solids (lb/T)
Settleable Solids (ml/l)
Total Nitrogen**** (lb/T)
NO" (Ib-N/T)
NO" (Ib-N/T)
NH (Ib-N/T)
Organic N (lb/T)
Total Phosphorus (lb/T)
Ortho-POj (ib-P/T)
Inorganic P (lb/T)
Total Soluble P (lb/T)
pH
Dissolved Oxygen (mg/l)
Temperature (°C)
Mean
29.8
1983 *
18.19
26.32
I1*. 71*
25.1*9
0.83
10.1
0.1608
0.0078
0.0000
0.01*90
0.101*0
0.0510
0.0110
0.0110
0.0170
1*.3
10.0
15.8
Range
22.5-37.0
750-3700
6.88-3.91*
19.17-32.59
10.7lt-l8.25
19.82-31.59
0.12-1.53
5.2-15.0
0. 0900-0. 278U
0.0030-0.015U
0.0030-0.1390
0. 081*0-0. 12UO
0.0120-0.0560
0.0050-0.0220
0.0050-0.0220
0.0090-0.0250
U.2-l*.3
10.0-10.2
15.5-16.0
Std. Deviation
73.0
1533
6.75
5.90
0.70
6.9
0.0067
0.0780
0.0280
0.0220
0.0090
0.0090
0.0110
0.1
0.3
*0nly 1.1% of the total cherry pack vas pitted; therefore
Total" column omitted.
•"Calculated on a yield basis of 109 cases/ton (7).
•""Calculated from COD by using BOD/COD ratio of 0.56.
***"Calculated by summing components.
n% of
424
-------
Table 13. Royal Anne Cherry (Atlas-Pacific) Stemmer Effluent
Characteristics
Parameter
Flow (gpm)
(gpT)
(gal/case)*
COD (Ib/Ton)
BOD** (Ib/Ton)
Total Solids (lb/Ton)
Suspended Solids (lb/Ton)
Settleable Solids (ml/l)
Total Nitrogen*** (lb/T)
NO" (Ib-N/T)
NO" (Ib-N/T)
NH- (Ib-N/T)
Organic N (lb/T)
Total Phosphorus (lb/T)
Ortho-PO* (ib-P/T)
Inorganic P (lb/T)
Total Soluble P (lb/T)
pH
Dissolved Oxygen (mg/l)
Temperature (°C)
Mean
9^.71
568.
5.21
0.67
0.38
0.91
0.027
0.06
0.0000
0
0
0
0
0.0065
0.0032
0.0032
0.001*3
6.1
10.0
16.1
Std.
Range Deviation
77.0-112.0
U62-672
lt.2U-6.17
0.38-0.90
0.21-0.50
0.62-1.17
0.020-0.036
0-0.1
___
0.0052-0.0077
0.002U-O.OOU2
0. 0020-0. 00l4l
0. 0035-0. 005U
5.2-6.8
9.0-10.2
15.0-17.8
11.1*
69.
0.19
«_»
0.25
0.01
0.02
___
0.0018
0.0009
0.0011
0.0010
0.6
0.5
1.0
% of
Total
37.6
2.1*
3.3
3.1
— —
0.0
0
0
0
0
16.8
21.1
20.9
19.1
___
— _
—
"Calculated on a yield basis of 109 cases/ton (7); 1-1% of throughput
was pitted.
••Calculated from COD by using BOD/COD ratio of 0,56.
•••Calculated by summing components.
(67 percent of the total solids were combustible organics). In comparison
to snap bean processing, Lambert processing contributed more than five
times the COD and nearly four times the total solids, on a production
basis.
Like the Royal Anne, the Lambert cherry contributed the greatest portion
of each pollutant at the Dunkley pitters, as shown on Table 15.
Interestingly enough, the volatile solids percentage of the Lambert
pitter effluent was identical to that of the combined effluent: 67
percent. By contrast, the Royal Anne pitter effluent volatile solids
level was 96 percent or about 1.2 times that of the Royal Anne combined
effluent. Since pitter effluent is mainly diluted cherry juice, it
can be concluded from the above that the Royal Anne juice contained
425
-------
fewer inorganics and higher levels of combustible organics (such as
sugars) than the Lamberts. The difference, then, between the Royal Anne
Table lU. Total Plant Effluent Characteristics During Lambert Cherry
Processing (15 samples).
Parameter
Flow (gpm)
(gpT)
(gal/case)*
COD (lb/T)
BOD** (lb/T)
Total Solids (lb/T)
Suspended Solids (lb/T)
Settleable Solids (ml/l)
Total Nitrogen*** (lb/T)
NO^ (Ib-N/T)
NO" (Ib-N/T)
NH3 (Ib-N/T)
Organic N (lb/T)
Total Phosphorus (lb/T)
Ortho-P0| (lb-P/T)
Inorganic P (lb/T)
Total Soluble P (lb/T)
pH
Dissolved Oxygen (mg/l)
Temperature (°C)
Mean
182.6
913.
8.38
36.71
21.65
37.18
1.08
5.1
0.1U81
0.0153
0.0000
0.0099
0.1229
0.0705
0.0575
0.0628
0.0617
5.6
8.U
25.6
Range
101.7-253.9
509-1270
U. 67-11. 65
29.90-U6.6U
17.6U-27.52
2U.82-U6.21
0.61-1.79
0.2-12.0
O.OU7U-0.2317
0.0071-0.0308
—
O.OOU2-0.0169
0. 0361-0. 18UO
0.0573-0.0836
O.OU92-0.0673
0.0572-0.0708
O.OU52-0.0759
5.0-6.0
7.2-8.8
22.0-28.5
•Calculated on a yield basis of 109 cases/ton (7); 175? of throughput
was pitted.
**Calculated from COD by using BOD/COD ratio of 0.59.
***Calculated by summing components.
effluent COD (28 Ib/ton) and the Lambert effluent COD (37 Ib/ton) might
be attributed to differences in sugar content of the cherry juices, and
to differences in cherry juice volumes lost in the respective processes.
Bartlett Pears
The final commodity monitored during the second season was the Bartlett
pear. This study offered the opportunity to compare the pollutional
effects of two different types of mechanical peeling systems: the
older Ewald peelers and the more modern (Atlas Pacific) contour peelers.
426
-------
Table 15. Lambert Cherry (Dunkley) Fitter Effluent Characteristics (15 samples".
Parameter
Flow (gpm)
(gpT)
(gal/case)**
COD (ib/T)
BOD*** (Ib/T)
Total Solids (ib/T)
Suspended Solids (ib/T)
Settleable Solids (ml/l)
Total Nitrogen**** (lb/T)
N0~ (Ib-N/T)
W0~ (Ib-N/T)
1JH (Ib-N/T)
Organic N (lb/T)
Total Phosphorus (lb/T)
Ortho-POj (ib-P/T)
Inorganic P (lb/T)
Total Soluble P (lb/T)
pH
Dissolved Oxygen (mg/1)
Temperature (°C)
Mean
Ul.5
1081. *
9.91
36.26
21.39
36.72
1.07
8.1
0.1U09
0.0150
0.0000
0.0099
0.1160
0.0690
0.0570
0.0620
0.0610
it. 6
9.9
16.0
Range
30.0-50.5
717-1900
6. 57-17. U3
29.78-U5.U6
17.57-26.82
2U.60-U5.02
0.61-1.75
O.U-25.0
O.OU72-0.2029
0.0070-0.0300
O.OOU2-0.0169
0.0360-0.1560
0.0570-0.0770
O.OU90-0.0660
0.0570-0.0690
O.OU50-0.07UO
U.3-U.9
8. 7-10. U
lU.0-18.5
Std.
Deviation
6.1
3Ul.
5.76
5.75
0.36
8.2
—
0.0070
O.OOU5
0.0320
0.0070
0.0060
0.0030
0.0080
0.6
1.0
*0nly 17* of the total cherry pack vas pitted; therefore the
Total" column vas not applicable to these data.
**Calculated on a yield basis of 109 cases/ton (7).
***Calculated from COD using BOD/COD ratio of 0.59.
****Calculated by summing components.
% of
While the former peel the fruit by slicing over a pre-set contour, the
latter follow the specific contour of each pear, abrading the fruit and
thereby increasing the yield of saleable product by as much as 10 percent.
It was interesting to discover that, in this case, the newer design
was decidedly inferior to the older in waste management terms.
Figure U depicts the pear canning process. After initial grading, the
pears were peeled and then fluined in a sodium chloride brine (which
retarded the browning reaction on the peeled surfaces) to a fresh water
rinsing tank for removal of excess brine solution. After rinsing, the
pears were conveyed to trimming tables where blemishes were removed.
Severely disfigured pears were directed after trimr.ing from the main
process line to the "chopping" area, there to be processed for incorporation
427
-------
FINISHED
PRODUCT
Figure U. Bartlett Pear Canning
428
-------
into other types of products. After trimming, the fruit was canned and
cooked in FMC continuous cookers.
The total pear process effluent exhibited the characteristics listed in
Table 16. The process required about 2850 gallons of water per ton and
the vastewater contained nearly 57 Ibs total solids per ton (91 percent
volatile), about 95 percent of which was colloidal or soluble; 55 Ibs
COD were exerted per ton of raw product.
The pear wastes were, therefore, the strongest (in terms of chemical
oxygen demand) encountered in the second season, being about 1.5 times
stronger than those of Lambert cherries, 2.0 times stronger than Royal
Annes and 8 times stronger than green bean wastes. In both seasons'
Table 16.
Total Plant Effluent Characteristics During Bartlett Pear
Processing (2U samples).
Parameter
Flow (gpm)
(gpT)
(gal/case)*
COD (lb/T)
BOD** (lb/T)
Total Solids (lb/T)
Suspended Solids (lb/T)
Settleable Solids (ml/l)
Total Nitrogen*** (lb/T)
NOg (lb-N/T)
NO;; (lb-N/T)
NH3 (lb-N/T)
Organic 11 (lb/T)
Total Phosphorus (lb/T)
Ortho-PO^ (ib-P/T)
Inorganic P (lb/T)
Total Soluble P (lb/T)
pH
Dissolved Oxygen (mg/l)
Temperature ( °C )
Mean
299.
2853.
35-05
5U.58
29. U7
56.87
2.82
U3.7
0.2615
0.05UO
0.0000
0.0039
0,2036
O.OU73
0.0297
0.0367
0.0378
U.U
9.7
17. U
Range
230-399
16UU-32U9
20.20-39-91
U2.3U-67.25
22.86-36.32
UO. 83-67. 53
1.89-3.87
3U. 0-65.0
0. 0883-0. 311U
0.0328-0.0727
0.0000-0.0069
0.1555-0.2318
0. 0306-0. 06U2
0.0210-0.0396
0. 0265-0. OU73
0. 0263-0. OU70
It. 1-5. 3
8.5-10.3
lit. 5-19. 5
Std.
Deviation
8.88
—
8.86
0.51
8.7
—
0.0120
0.0026
0.0277
0.0091
O.OOU9
0.0059
0.0057
0.5
1.0
Calculated on a yield basis of 8l.U cases/ton (7).
**Calculated from COD using BOD/COD ratio of 0.5U.
***Calculated by summing components.
429
-------
activities, the only stronger vastes were those emanating from the
beet canning process of the first season (75 lb COD/ton).
Tables 17 and 18 compare the effluents from the two types of peelers.
It can be seen that the newer-type contour peelers generated more than
twice the COD and total solids loads of the Ewald peelers. It is
unfortunate (from a pollution control standpoint) that the Evrald peelers
(being no longer available on the market) are being phased out of the
industry.
Table 17. Bartlett Pear Mechanical (Ewald) Peeler Effluent
Characteristics (18.eamples).
Parameter
Flow (gpm)»
(gpT)
(gal/case)**
COD (ib/T)
BOD*** (Ib/T)
Total Solids**** (Ib/T)
Suspended Solids (lb/T)
Settleable Solids (ml/l)
Total Nitrogen***** (lb/T)
NO" (Ib-N/T)
NO" (Ib-N/T)
NH (Ib-N/T)
Organic H (lb/T)
Total Phosphorus (lb/T)
Ortho-POj (ib-P/T)
Inorganic P (lb/T)
Total Soluble P (lb/T)
PH
Dissolved Oxygen (mg/l)
Temperature (°C)
Mean
36. Uo
1193.
1U.66
13.71
7.^0
13.25
0.36
3.U
0.01*00
0.0110
0.0000
0.0000
0.0290
0.0110
0.0063
0.0079
0.0081
U.6
10.2
1U.9
Std.
Range Deviation
26.50-^7.70
969-15 6U
11.90-19.21
7.9^-19.08
U. 29-10. 30
6.58-18.15
0.13
0.0-8.0
0.0250-0.0590
0.0070-0.0160
— _
0. 0180-0. OU30
0. 0060-0. 01U9
0.0036-0.0089
0.0050-0.0102
0.0056-0.0120
h. 1-5.1
9-7-10.5
13.5-16.0
6.59
218.
3.85
3.76
0.18-0.65
2.9
0.0030
—
— _
0.0080
0.0030
0.0018
0.0018
0.0022
0.7
1.0
*Four peelers operating.
•'Calculated on a yield basis of 81. U cases/ton (7).
•••Calculated from COD using BOD/COD ratio of 0.5^.
••••Volatile solids = 92 percent.
•••••Calculated by summing components.
430
-------
Table 18. Bartlett Pear Mechanical (Contour) Peeler Effluent
Characteristics (23 samples).
Parameter
Flow (gpm)*
(gpT)
(gal/case)**
COD (ib/T)
BOD*** (Ib/T)
Total Solids **** (ib/T)
Suspended Solids (lb/T)
Settleable Solids (ml/l)
Total Nitrogen***** (lb/T)
NO" (ib-N/T)
N0~ (Ib-N/T)
NH (Ib-N/T)
Organic N (lb/T)
Total Phosphorus (lb/T)
Ortho-PC^ (ib-P/T)
Inorganic P (lb/T)
Total Soluble P (lb/T)
pH
Dissolved Oxygen (mg/l)
Temperature (°C)
Mean
79.21
507.
6.23
31.57
17.05
29.61
2.01
61.1*
0.11*50
0.0290
0.0000
0.0000
0.1160
0.0190
0.0130
0.015
0.017
l*.2
9.9
15. U
Range
58.80-102.80
386-668
1*. 7^-8. 21
2U. 37-1*2. U5
13.16-22.92
23.23-37.73
1.57-2.86
1*0.0-100.0
0.1170-0.1970
0.0200-O.OU30
0.0970-0.151*0
0.0150-0.0230
0.0060-0.0190
0.0120-0.0180
0.0120-0.0200
3.9-U.5
8.9-10.5
13.5-17.5
Std.
Deviation
10. 8U
82.7
^^^
U.60
~H
3.91
0.39
18.1*
0.0060
0.0180
0.0030
0.0026
0.0020
0.0020
f- . ?
0.6
0.9
*Water usage averaged about U.5 gpm/peeler.
**Calculated on a yield basis of 81.1* cases/ton (7).
***Calculated from COD using BOD/COD ratio of 0.5U.
****Volatile solids = 96 percent.
*****Calculated by summing components.
CONCLUSIONS
The foregoing, summarized on Figures 5 through 7» where means and ranges
are depicted, has been only a summary of the findings of the first tvo
seasons' work. Subsequent papers detailing each commodity will be
published.
Among the general trends indicated by the above data are: 1) that some
characteristics presently being reported in text and reference books may
be obsolete and not representative of conditions in (an unknown number
of) today's canneries; 2) that fruit processing wastewater characteristics
vary distinctly with commodity and even, probably » with variety and
that, therefore (as has often been done) the values for one commodity
cannot justifiably be extrapolated from those for another; 3) that the
431
-------
3300
3000
2700
2400
2100
1800
£ 1500
a.
ci
** 1200
o
u. 900
600
300
—
—
:l
o
S
s
s
- s
—
1
at
E
Ul
o
^_
oc
i
^1
1
^
^
s
s
s
frn i-t.
1
|
^
'
^
S
'XXXXXXX,
s
s
N
^
k
i i i i i
Z CO (/> 0) (It
oc y K z 5
O ^ LJ
-------
o
o
CD
80
70
60
50
40
30
20
10
I
I
I
CO
UJ
cc
cc
UJ
0
h-
E
UJ
CD
z to
K. ^
o E
o cc
UJ
X
o
UJ
z
z
^
CO
UJ
UJ
CD
CO
z
UJ
CO
OL
z
CO
CO
cc
UJ
a.
1
H
Ul
.J
H
oc
CD
Figure 6. Biochemical Oxygen Demand Summary
433
-------
4.5
4.0
35
^
^ 3.0
(O
o
o 25
CO
o
Ul
o 2.0
UJ
a.
(A
3 1-5
I.O
05
R
-
- 5
^
ivj
i
CO
Ul
K
O
K
lit
GO
3E
i
^
i
^
^
bJ
CO
UJ
tc
cc
Ul
X
0
UJ
i
J
^
^
vxxxxxxxx
^
^
^
5
s
N
^
^
^
^
1
^
X
5
^
\
\
N
s
I \.
f 1 1
CO 10
z ec
UJ UJ
m a.
OL J-
< ^
CO rf
cr
OQ
Figure 7. Suspended Solids Summary
434
-------
greatest portion of the pollutant load generated in cherry processing
occurs at a single source, the pitters, and that, perhaps, this vaste
stream should be incorporated into a "by-product recovery system; and
h) that new designs for processing equipment should "be evaluated in
terms of vaste generation, as veil as the more production-oriented
parameters.
The availability of reliable, contemporary vastevater characterization
data (such as the foregoing) should facilitate the efficient,
enlightened approaches to solving environmental problems nov being
demanded of industry and government by an aroused public.
ACKNOWLEDGMENTS
The following staff members of the O.S.U. Department of Food Science and
Technology vere instrumental in the preparation of this paper through
laboratory analysis, data interpretation, or manuscript reviev and their
participation is gratefully acknowledged: J. E. Borden, W. D. Davidson,
R. F. Cain, C. Phillips, C. Neshyba, R. Cain, S. Pierce, L. Grande,
E. Brineman, M. Fitzsimmons, G. Higgins, W. Sayed, K. Leistikow, J. Lyche,
B. Montgomery, N. Thomas and P. Butz. Furthermore, this study could
not have been undertaken vithout the villing cooperation of the personnel
of the participating plants, vhich the auttiors sincerely appreciated.
DISCLAIMER
Mention of trade names or commercial products does not constitute
endorsement or recommendation for use.
435
-------
REFERENCES
1. RUDOLFS, W. (ed.). Industrial Wastes. L.E.C. Publishers, Valley
Stream, New York. U97 p. (1953).
2. GURNHAM, C. F. (ed.) Industrial Wastevater Control. Academic
Press, New York. Vf6 p. (1965).
3. LUND, H. F. (ed.) Industrial Pollution Control Handbook. McGraw-
Hill, New York. 8Vf p. (1971).
k. NEMEROW, N. L. Liquid Waste of Industry: Theories, Practices, and
Treatment. Addison-Wesley Publishing Co., Reading, Massachusetts.
58U p. (1971).
5. SANITARY ENGINEERING RESEARCH COMMITTEE OF THE SANITARY ENGINEERING
DIVISION, A.S.C.E. Research Needs in Sanitary Engineering. Journal
of the Sanitary Engineering Division, Proceedings of the American
Society of Civil Engineers SAZ: 299 (1972).
6. SODERQUIST, M.R. and TAYLOR, D.W. A Mobile Laboratory for Food
Processing Wastewater Analyses. ASAE Paper No. 71-^18. American
Society of Agricultural Engineers, St. Joseph, Michigan. 23 p.
(1971).
7. .^ . 1971-1972 Yearbook. Canner Packer 1^0:9. 102 p.
(197D.
8. SAWYER, C. N. Biological Treatment of Sewage and Industrial
Wastes. Vol. 1. (J. McCabe and W. W. Eckenfelder, Jr., eds.).
Reinhold Publishing Co., New York. (1956).
9. TARAS, M. J., GREENSBERG, A. E., HOAK, R. D. AND RAND, M. C.
(eds.). Standard Methods for the Examination of Water and Waste-
water, 12th Edition. American Public Health Association, New
York. (1965).
10. JANKOVIC, S. G.t MITCHELL, D. T. AND BUZZELL, J. C., JR.
Measurement of Phosphorus in Wastewater. Water and Sewage Works
(1967).
A 36
-------
PROGRESS REPORT: SEAFOODS PROCESSING
WASTEWATER CHARACTERIZATION*
M. R. Soderquist**, G. I. Blanton, Jr.**, J. E. Border;** and
K. S. Hilderbrand**
INTRODUCTION
The Department of Food Science and Technology at Oregon State
University is currently involved in a research project in vhich the
effluents from seafoods processing plants are "being monitored, sampled
and analyzed. This work has evolved from two other Departmental
projects: l) a study of the current"state-of-the-art" of seafoods
processing waste management ,( 1 ) and 2) a waste characterization study
of the Oregon fruit and vegetable processing industry. (2) The study
is being funded mainly "by the Environmental Protection Agency and the
National Canners Association.
In November, 1971, the Department's mobile laboratory (3) Vas located
at the Oregon State University Seafoods Laboratory in Astoria, Oregon.
From that base the wastes produced by roughly a dozen different seafoods
plants were being monitored as they processed six seasonal commodities:
Dungeness crab, bottom fish, shrimp, clams, tuna and salmon. In
addition, the wastes generated in the production of by-products were
being characterized.
Using methods outlined in a previous paper, flow, temperature,
dissolved oxygen and pH were monitored on-site and flow proportioned
composite samples were subsequently analyzed for total-, dissolved-,
volatile-, settleable- and suspended-solids, chemical oxygen demand
(COD), five-day- (BOD) and ultimate-biochemical oxygen demand (BOD^^)
oil and grease, nitrite, nitrate, organic nitrogen, ammonia, ortho-
phosphate, total inorganic phosphorus, soluble phosphorus, total
phosphorus, fecal coliform, total coliform and fecal streptococcus.
At this writing three months' Dungeness crab wastewater data have been
gathered. This paper presents the results of that work.
*This investigation was supported by funds from the Environmental
Protection Agency under Grant No. 801007, the National Canners
Association, the Oregon Agricultural Experiment Station, a Public
Health Service Biomedical Sciences Support Grant to Oregon State
University, and the Oregon State University Computer Center. Oregon
Agricultural Experiment Station Technical Paper No. 3407
**Department of Food Science and Technology, Oregon State University,
Corvallis, Oregon.
437
-------
THE DUNGENESS CRAB PROCESS
Many factors influence the character and volumes of waste-waters
discharged from a seafood (or any food) processing plant.^^ These
include:
1) variability in raw product supply;
2) condition of raw product (e.g., maturity of animal and storage
time in vessel);
3) species being processed (seafoods yields vary from 15 to 100
percent);
!*) harvesting method;
5) degree of pre-processing, if any (Gulf of Mexico shrimp
are often beheaded at sea, as is much of the Alaskan halibut
catch);
6) manufacturing process;
T) form of finished product (canned prime fillet vs. fish paste,
for instance);
8) location of plant (New England vs. Southern California;
congested metropolitan area vs. remote, isolated site);
9) plant age;
10) maximum production capacity and specific operating level;
11) operating schedule (intermittent vs. continuous);
12) water supply availability and cost; and
13) waste treatment and/or disposal methods required and their
costs.
Except for item (3) above, each of these variables is applicable to the
Dungeness crab processing industry.
The Dungeness crab process is depicted schematically in Figure 1.
Variations in this general scheme for specific plants will be pointed
out as each plant's effluent is discussed. Three plants were
monitored. The following process descriptions refer to those plants.
After delivery from the vessel the crabs, unless they were to be
marketed whole, were first butchered. The backs were detached, the
viscera removed and the legs separated from the bodies. Some plants
flumed the solids from this process to a central screen, but most
employed dry capture techniques. In the latter instance the only flows
from the butchering area were clean-up waters.
The next unit operation was bleeding-rinsing. The crab pieces were
either conveyed via belt below a water spray or were packed in large
steel baskets and submerged in circulating rinsewater. In either case
a continuous wastewater flow resulted.
The crab parts (and whole crab) were then cooked in boiling water.
Whole crab were boiled in a 50,000-60,000 mg/1 (as C1-) sodium chloride
solution containing 650-800 mg/1 citric acid for 20 to 30 minutes.
438
-------
BLEEDING OR
RINSING
COOKING
FINISHED
PRODUCT
Figure 1. The Dungeness crab process
Whereas the salt vas used for seasoning, the citric acid facilitated
shell cleaning ("by loosening adhering material) in a subsequent step.
Crab sections, on the other hand, were simply water boiled for twelve
minutes or so. The wastewater flows from this step, of course, were
intermittant, occuring whenever a cooker was "dumped."
As was "bleeding-rinsing, the next step, cooling, was accomplished in
two ways. The simpler method employed was to spray the hot crabs with
water, resulting in a continuous wastewater flow. The more
sophisticated plants employed immersion of the crab-filled baskets in
tanks into which cooling water was constantly flowing. After twenty
minutes the baskets were removed and allowed to drain. The resulting
wastewaters consisted of a continuous flow (the cooling tank overflow)
and discrete flows (cooling tank "dumps" plus crab basket drainage).
439
-------
In all plants surveyed, "picking" of the meat from the shell was a
manual operation. "Picking stock" included "bodies and legs. Yields
varied from 17 to 27 percent. This variation was mainly a function of
the maturity of the animals; yields increased as the season progressed.
No water was used in this unit operation except during wash-down.
The cleaned meat was conveyed to brine tanks where loose shell was
separated from the meat by flotation. The 100,000 to 200,000 mg/1
(as Cl~) sodium chloride solutions were discharged intermittantly.
Most of the salt solution remaining on the meat was removed in the
next unit operation, the (immersion) rinse tanks. The discharges
from these tanks were continuous and contained 1500-2000 mg Cl~/l.
After rinsing the meat was drained and packed. Whether packing in
cardboard and plastic for the fresh market or canning the meat, this
operation contributed little to the wastewater systems except clean-up
flows.
In those instances where meat was canned, the final step was retorting;
in those where fresh packing was practiced, the last step was
refrigeration. Both processes used water, but neither appreciably
contaminated it, so these flows were ignored.
WASTEWATER CHARACTERISTICS
Although three Dungeness crab processing plants were monitored regularly
during the three-month period, heavy emphasis was placed on that plant
considered most typical. From seven to fourteen full-shift flow-
proportioned samples were collected from each operation. Sampling
frequency was determined by regularity and uniformity of discharge;
the more erratic units were sampled more frequently. The other two
plants were sampled less frequently; data gathered from these plants
demonstrated variability in wastewater strengths and flows from plant
to plant.
Influence of plant size on wastewater values could not be reliably
demonstrated in this study because the three plants had similar
production capacities: from six to eight tons per shift. Further
studies, however, may offer the opportunity to investigate the size
vs. efficiency of utilization relationship.
Tables 1 through 11 refer to the plant most frequently monitored,
designated Plant No. 1. The reader will note the absence of
bacteriological data. This is because that phase of the study, being
independently funded (by the National Canners Association), was begun
several months after the initiation of the "parent" EPA-funded project.
These data were not in final form at this writing.
440
-------
Table 1 reveals the nature of the combined wastewater stream, both with
and without the contribution of the whole crab processing line. A
typical plant would handle both picking stock and whole crab, but the
bulk of the process would be devoted to picking stock. The dual
presentation should allow a plant engineer or a wastewater treatment
plant designer to consider the influence of either system alone. On
this table standard deviations are not listed because the values listed
represent summations of means, maxima and minima from the sub-processes.
It may be of interest to compare Dungeness crab processing wastewater
strengths with those of other food processing operations. The O.S.U.
fruit and vegetable study(2) concluded that green bean processing
generates about 7 lb COD/ton of raw product. Other values presented
included Royal Anne cherries, 28 Ib/T; sweet corn, 3^ Ib/T; Lambert
cherries, 37 Ib/T; Bartlett pears, 55 Ib/T; and red beets, 75 Ib/T.
By comparison, then, the Dungeness crab plant no. 1, at 22 Ib COD/T,
falls below most fruits and vegetables characterized to date. The
values for plants numbers 2 and 3 will be found in the Appendix. Plant
no. 2 (Table 12) produced nearly identical COD loadings, whereas Plant
no. 3 (Table 22) generated half again as much. The latter plant,
however, was operating a temporary processing line while its main
facilities were being remodeled. This may have led to the higher
wastewater loadings, reflecting lower yields caused by less-than-optimum
processing conditions.
Water consumption figures, on the other hand, present a different
picture. The range for fruits and vegetables in the above-mentioned
study(2) was 900-2900 gal/T. Water use in Dungeness crab plant no. 1
was about 3600 gal/T. Reference to the Appendix indicates that water
consumption in plant no. 2 (Table 12) was about 5100 gal/T (excluding
shell flume) and in plant no. 3 (Table 22), about 5011 gal/T (excluding
butchering flume). The authors doubt that Dungeness crab processing
inherently requires more than twice the water used in the average
fruit and vegetable processing plant. It therefore seems likely that
a water conservation program would effect significant cost savings
(in terms of lowered water bills only—since few, if any, crab plants
now pay flow-based sewerage fees) in the average crab plant.
Perhaps the most striking difference between fruit and vegetable
processing wastes and Dungeness crab wastewaters is the nutrient
(nitrogen and phosphorus) content. The crab wastewater level of both
nutrients was an order of magnitude greater than those values of the
previous study(2). Organic nitrogen levels, especially, were high.
Concentrations of 1500. mg organic %/l were not uncommon.
For satisfactory biological waste treatment, a minimal BOD:W:P ratio
is said to be about 150:5:1 (5). From Table 1, the BOD:N:P ratio of
43:4.4:1 can be calculated. This indicates that sufficient nitrogen
441
-------
Table 1. Combined Wastewater Characteristics Plant No. 1
Picking Stock Only
Parameter
Flow (gpm)*
(gpT)
COD (ib/T)
BOD** (Ib/T)
Total Solids (lb/T)
Settleable Solids (ml/l)
Suspended Solids (lb/T)
Volatile Solids (%)
Total Nitrogen*** (lb/T)
N0§ (Ib-N/T)
NOg- (lb-N/T)
NHo (lb-N/T)
Organic N (lb/T)
Total Phosphorus (lb/T)
Ortho-POr (ib-P/T)
Inorganic P (lb/T)
Total Soluble P (lb/T)
pH
Dissolved Oxygen (mg/l)
Temperature (<>C)
Mean
Picking Stock & Whole Crabs
Mean
30.57
3561*. 85
22.23
13.16
171.86
92. U
5.33
34.2
3.010
0.0073
0.00036
0.1889
2.8lH
0.3053
0.11*32
0.1958
0.2502
7.3
11.06
9.*
—
___
ll*. 65-31. 11
8.6U-18.35
98.70-2U8.o6
39. 55-1^9. 7
2.59-8.^92
24.2-43.6
2.0U9-U.231
0.001*5-0.0122
0.00027-0.00111
0.1213-0.2818
1.923-^.128
0.1279-0.5512
0.0557-0.2893
0.0821-0.3306
0. 0979-0. U650
7.1-8.5
10.56-12.02
6.91-13.1*6
32.93
38U0.1
33.90
20.00
200.56
93.7
6.62
35.5
U.2972
0.0076
0.0001*2
0.3562
3.933
0.372
0.161*5
0.2307
0.301*2
7.3
11.06
9.U
—__
— —
23.05-1*5.72
13.600-26.975
221.7-890.06
39.65-152.2
^>7-q.96
24.8-47.0
3.0611-6.11*60
0.001*59-0.01265
0.0003-0.001222
0.2572-0.1*781
2.799-5.651*
0.1653-0.65!*
0.0625-0.3238
0.0978-0.3866
0.1272-0.51*1*5
7.1-8.5
10.56-12.02
6.91-13.1*6
*£ water volumes discharged/^ operating times on days when system was monitored.
**Calculated from COD using BOD/COD = 0.59.
***Calculated by summing components.
-------
Table 2. Butchering Area Clean-up Wastewater Characteristics Plant No. 1
Parameter
Flow (gpm)*
(gpT)
COD (lb/T)
BOD** (lb/T)
Total Solids (lb/T)
Settleable Solids (ml/1)
Suspended Solids (lb/T)
Volatile Solids (%)
Total Nitrogen*** (lb/T)
N03 (Ib-N/T)
NO £ (Ib-N/T)
NH3 (Ib-N/T)
Organic N (lb/T)
Total Phosphorus (lb/T)
Ortho-PO^ (ib-P/T)
Inorganic P (lb/T)
Total Soluble P (lb/T)
PH
Dissolved Oxygen (mg/l)
Temperature ( °C )
Mean
29.81
336.3
2.67
1.575
3.77
3.6
0.59
1*8.1*7
0.2731
0.0008
o.ooooU
0.0153
0.257
0.0210
0.0088
0.0137
0.01U8
7.5
11.87
8.2
Range
185.1-1*98.7
1.22-1*. 78
0.720-2.82
1.05-8.22
1.7-7.5
0.153-1.07
1*1*. 0-52. 85
0.0993-0.5163
0.0005-0.0011
0.00002-0.00070
0.0058-0.0275
0.093-0.1*87
0.0092-0.0395
0.0029-0.0183
0.0058-0.021*9
0.0058-0.0283
7.U-7.6
___
— -
Standard
Deviation
mmmmmm
128.9
1.50
_ —
3.05
2.0
0.30
3.1*5
0.0002
o.ooooi*
0.0091
0.171
0.013
0.0068
0.0086
o.oioi*
— __
0.35
2.2
(7 samples)
% of Plant
Total
__.
9.^3
12.01
11.97
2.19
11.06
—
9.07
10.96
11.11
8.10
9.13
6.88
6.15
7.00
5.92
— _
___
— _
*£ vater volumes discharged/ I operating times on days when area was sampled.
**Calculated from COD using BOD/COD = 0.59.
***Calculated by summing components.
-------
Table 3.
Parameter
Flow ( gpm ) *
(KPT)
COD (Ib/T)
BOD** (ib/T)
Total Solids (Ib/T)
Settleable Solids (ral/l)
Suspended Solids (ib/T)
Volatile Solids (%)
Total Nitrogen*** (Ib/T)
NO, (ib-N/T)
N0§ (Ib-N/T)
NH3 (Ib-N/T)
Organic N (Ib/T)
Total Phosphorus (lb/T)
Ortho-POr (Ib-P/T)
Inorganic P (lb/T)
Total Soluble P (lb/T)
PH
Dissolved Oxygen (mg/l)
Temperature (°C)
Bleeding Tank
Mean
T.96
1*35.6
2.21
1.30
3.U5
0.5
0.29
1*9.3^
0.21*077
0.00053
o.ooooi*
0.0112
0.229
O.OJ51
0.001*5
0.0060
0.011
7.3
11.5
6.9
Overflov Characteristics Plant
Range
__.
299.2-610.9
2,ol*-2.37
1.20-1.1*0
2.87-3.77
0.1-0.8
0.12-0.50
1*1*. 75-57. 15
0.21992-0.27131*
0.00038-0.0008U
___
0.0085-0.0155
0.211-0.255
0.0101-0.0228
0.0039-0.0051
0.0055-0.0069
0.0086-0.011*
6.8-7.7
...
MMkW
Standard
Deviation
11*7.07
O.ll*
___
0.1*0
o.i*
0.17
5.25
_ — —
0.00027
_ _ _
0.0038
0.023
0.0068
0.0005
0.0008
0.0028
0.33
1.1*
No. 1 (5 samples)
% of Bleeding
Tank Total
80.65
76.1*7
76.1*7
80.61
_«.*»
76.32
___
73.71
66.25
66.67
75.68
73.63
81.75
71.1*3
71.1*3
72.85
_— -.
___
«__
% of Plant
Total
12.5
9.91*
9.88
2.01
___
0.05
___
32.1*1*
7.26
11.11
5.93
8.1U
1*.95
3.1U
3.06
U.52
—_—
___
— — — •
*E water volumes discharged/E operating times on days when unit was sampled.
**Calculated from COD using BOD/COD = 0.59.
***Calculated by summing components.
-------
Table 1*. Bleeding Tank Discrete Discharge Characteristics Plant No. 1 (5 samples)
Parameter
Flow (gpm)*
(gpT)
COD (ib/T)
BOD** (Ib/T)
Total Solids (lb/T)
Settleable Solids (ml/l)
Suspended Solids (lb/T)
Volatile Solids (%}
Total Nitrogen*** (lb/T)
NO' (ib-N/T)
NO* (lb-N/T)
NIC (lb-N/T)
Organic N (lb/T)
Total Phosphorus (lb/T)
Ortho-P0= (ib-P/T)
Inorganic P (lb/T)
Total Soluble P (lb/T)
PH
Dissolved Oxygen (mg/l)
Temperature ( °C )
Mean
1.69
105.5
0.68
0.1*0
0.83
0.7
0.09
Vf.79
0.08589
0.00027
0.00002
0.0036
0.082
0.0036
0.0018
0.002U
o.ooUi
7.1
11. U5
7.2
Range
58.9-371.5
0.37-1.10
0.22-0.65
0.28-1.68
0.3-1.3
0.038-0.112
U6.0-50.8
0.06002-0.1261*0
0.00021-0.00032
0.00002-0.00003
0.0018-0.0051
0.058-0.121
0.0015-0.0071
0.0003-0.0028
0.0005-0.0037
0.0015-0.0066
7.0-7.3
— __
™~™
Standard
Deviation
0.38
0.75
0.5
0.035
2.28
_ —
0.00006
0.00001
0.0016
0.029
0.0031
0.0013
0.0017
0.0036
___
0.35
1.5
% of Bleeding
Tank Total
19.35
32.53
23.53
19.39
23.68
__-_
26.29
33.75
33.33
2U.32
26.37
19.25
28.57
28.57
27.15
_ —
— _
M««
% of Plant
Total
2.96
3.06
3.01*
0.148
5.UU
___
1H.07
3.69
5.56
1.91
2.91
1.18
1.26
1.23
1.6U
—
___
^ ^^
*l water volumes discharged/Z operating times on days when unit was sampled.
**Calculated from COD using BOD/COD - 0.59.
***Calculated by summing components.
-------
Table 5« Section
Parameter
Flow (gpm)*
(gpT)
COD (ib/T)
BOD** (lb/T)
Total Solids (ib/T)
Settleable Solids (ml/l)
Suspended Solids (lb/T)
Volatile Solids (%}
Total Nitrogen*** (lb/T)
NOo (Ib-N/T)
WO; (Ib-N/T)
NIC (lb-N/T)
Organic N (lb/T)
Total Phosphorus (lb/T)
Ortho-PO? (ib-P/T)
Inorganic P (lb/T)
Total Soluble P (lb/T)
pH .
Dissolved Oxygen (mg/l)
Temperature (°C)
Cooker Wastevater
Mean
1.1*0
87.92
5.1*0
3.78
9.31
1.7
1.1U
55.1+9
0.7721*1
0.00010
0.00001
0.0813
0.691
0.01*1*8
0.0097
0.021*2
0.030U
8.5
— -—
Characteristics Plant
Range
—
50.37-385.05
U. 01-6. 55
2.81-U.59
7.06-13.57
0.5-U.O
0.606-1.928
U6. 0-60. 35
0.63256-0.95586
0.00005-0.00025
0. 000011-0. OOOOlU
0.05^5-O.llUO
0. 578-0. 8U2
0.0202-0.0603
0. 0035-0. Ol^U
0.0183-0.0336
0. 0185-0. Ql* 11
8.»*-8.6
— — —
No. 1 (11
Standard
Deviation
...
—
1.02
2.23
1.1
0.1*58
5.69
0.00007
0.000002
0.0223
0.103
0.0159
0.00^3
0.0063
0.0089
_ —
— — —
samples )
% of Plant
Total
...
2.U6
2l*.29
28.72
5.1*1
___
21.38
25.65
1.37
2.78
1*3. OU
21*. 56
11*. 67
6.77
12.36
12.15
—
—
.»_•
*Z water volumes discharged/£ operating times on days when unit was sampled,
**Calculated from COD using BOD/COD = 0.70.
***Calculated by summing components.
-------
Table 6. Whole Crab
Parameter
Flow ( gpm ) *
(gpT)
COD (lb/T)
BOD** ((lb/T)
Total Solids (lb/T)
Settleable Solids (ml/1)
Suspended Solids (lb/T)
Volatile Solids (%}
Total Nitrogen*** (lb/T)
NO; (Ib-N/T)
N0| (Ib-N/T)
NH3 (Ib-N/T)
Organic N (lb/T)
Total Phosphorus (lb/T)
Ortho-PofJ (Ib-P/T)
Inorganic P (lb/T)
Total Soluble P (lb/T)
PH
Dissolved Oxygen (mg/1)
Temperature (°C)
Cooker Wastewater
Mean
0.7^7
275.2
11.67
6.1*2
287
1.3
1.29
13.29
1.28666
0.00030
0.00006
0.1673
1.119
0.0671
0.0213
0.031*9
0.051*0
7.5
—
...
Characteristics Plant No. 1
Range
...
129.2-877.3
8.1*0-11*. 61
1*. 62-8.01*
123-61*2
0.1-2.5
0.890-1-570
5.65-33.9
1.01202-1.72286
0.00009-0.0001*5
0.000032-0.00011
0.1359-0.1963
0.876-1.526
0.037l*-0.1028
0.0068-0.031*5
0.0157-0.0560
0.0293-0.0795
6.1-8.2
...
(8 samples)
Standard
Deviation
«»«
2.09
...
176
.8
0.261
9.37
—
0.00015
o.ooooi*
0.0235
0.225
0.0221*
0.0105
0.0138
0.0179
*£ water volumes discharged/2 operating times on days when unit was sampled.
**Calculated from COD using BOD/COD = 0.55.
***Calculated by summing components.
-------
00
Table 7.
Parameter
Flow (gpm)*
(6PT)
COD (ib/T)
BOD** (ib'/T)
Total Solids (ib/T)
Settleable Solids (ml/l)
Suspended Solids (ib/T)
Volatile Solids (%)
Total Nitrogen*** (lb/T)
NO^ (ib-N/T)
NO| (Ib-N/T)
' NH (Ib-N/T)
Organic N (lb/T)
Total Phosphorus (lb/T)
Ortho-POf (Ib-P/T)
Inorganic P (lb/T)
Total Soluble P (lb/T)
PH
Dissolved Oxygen (rag/1 )
Temperature (°c)
Cooling Tank
Mean
21.87
1067. U5
1.U2
0.71
3.18
0.2
0.20
32.H
0.15^5
0.0026
0.0001
0.0178
0.131*
0.0216
0.0101
0.0111
0.0163
7.2
10.56
13.5
Overflow Characteristics Plant
Range
1022.2-1215.6
1.20-1.63
0.60-0.815
2.614-3.71
0.05-0.6
0.116-0.309
20. 3-^6.9
0.1188-0.1863
0.0021-0.0030
___
0.0167-0.0193
0. 100-0. 16U
0.0195-0.0230
0.0082-0.0113
0.0085-0. 01 31*
0.0115-0.0213
7.1-7.6
«B«M^
Standard
Deviation
123. Ul
0.21
—
0.75
0.2
0.093
11.3
0.0005
___
0.0013
0.032
0.0019
0.0016
0.0025
O.OOU9
0.1808
1.9
No. 1 (1* samples)
% of Cooling
Tank Total
90.31
95.30
95.30
79.10
58.82
___
95.37
92.86
93.1*6
93.20
95.71
9^.32
96.19
95.69
96>5
—
—
...
% of Plant
Total
—
29.91*
6.39
5.^0
1.85
_ —
3.75
—
5.13
35.62
27.78
9.1*2
U.76
7.08
7.05
5.67
6.51
—
—
*Z water volumes discharged/I operating times on days when unit was sampled.
^Calculated from COD using BOD/COD - 0.50.
***Calculated by summing components.
-------
vo
Table 8. Cooling Tank Discrete Discharge Characteristics Plant No. 1 (5 samples)
Parameter
Flow (gpm)*
(gpT)
COD (lb/T)
BOD** (lb/T)
Total Solids (lb/T)
Settleable Solids (ml/l)
Suspended Solids (lb/T)
Volatile Solids (%}
Total Nitrogen*** (lb/T)
NO^ (lb-N/T)
NO- (lb-N/T)
NIL. (lb-N/T)
Organic N (lb/T)
Total Phosphorus (lb/T)
Ortho-PO* (Ib-P/T)
Inorganic P (lb/T)
Total Soluble P (lb/T)
PH
Dissolved Oxygen (mg/l)
Temperature (°C)
Mean
1.1*
rU.5
0.07
0.03
0.81*
o.U
0.1^
27.05
0.0075
0.00020
0.000007
0.0013
0.006
0,0013
o.oooU
0.0005
0.0006
7.1
11.25
12.5
Range
66.1-52U.3
0.03-0.12
0.015-0.06
0.25-1.36
___
0.007-0.023
12.85-52.5
.0032-0.0129
0.00010-00030
0.000006-0.000008
0.0011-0.0016
0.002-0.011
0. 0005-0. 002U
0.0001-0.0006
0.000^-0.0007
O.OOOU-0.0009
6.9-7.5
— „
— — •-*
Standard
Deviation
_—_
O.OU
— _
0.56
0.2
0.007
22.09
___
0.00010
0.000001
0.0002
o.ooi*
0.0010
0.0003
0.0002
0.0003
— -
1.20
2.3
% of Cooling
Tank Total
9.69
U.70
1*.70
20.90
___
Ul.18
___
I*. 63
I.Ik
6.5U
6.80
U.29
5.68
3.81
U.31
3.55
___
_ —
••— ^
% of Plant
Total
3.21
0.31
0.27
O.U8
___
2.62
___
0.25
o Yli
i nji
0.69
0.21
0.1+3
0.28
0.26
0.2U
___
___
— — —
*Z water volumes discharged/Z operating times on days when unit was sampled.
**Calculated from COD using BOD/COD = 0.50.
***Calculated by summing components.
-------
Ul
O
Table 9. Picking
Parameter
Flow (gpm)*
(gpT)
COD (Ib/T)
BOD** (ib/T)
Total Solids (lb/T)
Settleable Solids (ml/l)
Suspended Solids (Ib/T)
Volatile Solids (%)
Total Nitrogen*** (lb/T)
NOT (ib-N/T)
NOf (Ib-N/T)
HE, (Ib-N/T)
Organic K (lb/T)
Total Phosphorus (lb/T)
Ortho-POjj (ib-P/T)
Inorganic P (lb/T)
Total Soluble P (lb/T)
PH
Dissolved Oxygen (mg/l)
Temperature (° C )
Area Clean-up
Mean
27.^8
285.02
0.79
o.uu
1.72
6.3
0.37
52.09
0.0917
0.003
0.00001
0.006U
0.085
O.OlUl
0.0078
0. 009U
0.010U
8.3
11. lU
8.7
Flow Characteristics
Range
...
51.8-923.0
0.21-l.UU
0.12-0.81
0.29-U.19
3.8-13.0
0.165-0.681
13.6^-67.55
0.01U7-0.1982
0.00011-0.00062
0.000008-0.00001
0.0016-0.0136
0.013-0.181*
0.0039-0.0300
0. 0021-0. OlltU
0. 0023-0. 017^
0. 0022-0. 020U
7.3-8.7
—
___
Plant Ho. 1 (8
Standard
Deviation
_„
277.9^
0.55
__ _
1.U9
3.3
0.17
17.51
___
0.0002U
0.000001
0.00i*9
0.073
0.0115
0.005U
0.0070
0.0083
___
0.56
1.1*
samples)
% of Plant
Total
—
7.99
3.55
5.31*
1.00
___
6.9U
___
3.05
U.ll
2.76
3.39
3.02
U.62
5.U5
U.80
U.16
_-_
—
— —
*£ water volumes discharged/! operating times on days when area was sampled.
**Calculated from COD using BOD/COD « 0.56.
***Calculated by summing components.
-------
V/i
Table 10.
Parameter
Flow (gpm)*
(gpT)
COD (ib/T)
BOD** (Ib/T)
Total Solids (Ib/T)
Settleable Solids (ml/l)
Suspended Solids (ib/T)
Volatile Solids (%)
Total Nitrogen*** (lb/T)
NOS (ib-N/T)
NOg (lb-N/T)
NH3 (lb-N/T)
Organic N (lb/T)
Total Phosphorus (lb/T)
Ortho-PO^ (ib-P/T)
Inorganic P (lb/T)
Total Soluble P (lb/T)
pH
Dissolved Oxygen (mg/l)
Temperature (°C)
Brine Tank Discharge
Mean
0.75
TO. 6
6.00
3.18
129.91
76.7
1.99
15-11
0.9705
0.00005
0.00002
0.0335
0.937
0.1217
0.0573
0.0813
0.103U
7.1*
11.19
9.7
Characteristics Plant
Range
22.9-107.6
3.57-8.11
1.89-1*. 30
70.93-l8U.12
35-120
1. 015-3. 03**
1*. 8-31. 35
0. 6321-1. 1*011
0.00000-0.00009
0.00000-0.00003
0.0221-0.01*50
0.610-1.356
0.0290-0.21*03
0.008U-0.ll*00
0.0155-0.11*08
0.0181-0.2061*
7,0-8,1
_-_
—
No. 1 (lU
Standard
samples )
% of Plant
Deviation Total
_—
1.1*2
___
33.88
25.2
0.66
9.12
___
0.00003
0.00001
0.0073
0.222
0.0676
0.01*08
0.0636
0.06l6
0.69
1.8
1.98
26.99
2U.16
75.59
—
37.31*
—
32.2U
0.68
5.56
17.73
33.30
39.86
1*0.01
1*1.52
1*1.33
—
—
••— —
*E water volumes discharged/Z operating times on days when unit was sampled.
**Calculated from COD using BOD/COD = 0.53.
***Calculated by summing components.
-------
N5
Table 11.
Parameter
Flow (gpm)*
(gpT)
COD (Ib/T)
BOD** (Ib/T)
Total Solids (ib/T)
Settleable Solids (ml/1)
Suspended Solids (ib/T)
Volatile Solids (%)
Total Nitrogen*** (lb/T)
N0§ (Ib-N/T)
NOjj (Ib-N/T)
NH3 (Ib-N/T)
Organic N (lb/T)
Total Phosphorus (lb/T)
Ortho-POf (ib-P/T)
Inorganic P (lb/T)
Total Soluble P (lb/T)
pH
Dissolved Oxygen (mg/l)
Temperature (°C)
Rinse Tank Overflow
Mean
10.96
1061.9
2.99
2.15
18.85
1.0
0.52
13.76
O.UlUo
0.0021*
0.00011
'0.0185
0.393
0.0621
0.01*28
0.01*72
0.0589
7.2
12.02
7.6
Characteristics Plant
Range
_
708.8-27U2.U
2.00-5.01
l.UU-3.61
13.33-27.1*1*
0.5-2.0
0.359-0.732
9.65-17.00
0.2682-0.751*1*
0.0010-0.0057
0.00007-0.00018
0.0092-0.01*06
0.258-0.708
0.031*0-0.1258
0.0263-0.082!*
0.0253-0.0892
0.0313-0.1258
6.9-7.9
_„
— —— «
No. 1 (10
Standard
Deviation
325.5
0.90
.— M
5.05
0.513
0.12
2.61*
«••»••
0.0012
0.00006
0.0102
0.111
0.021*2
0.011*8
0.0180
0.0236
___
0.23
1.3
samples )
% of Plant
Total
29.79
13.^5
16.3U
10.96
_—-.
9.76
13.75
32.88
30.56
9.79
13.97
20.31*
29.89
2l*.ll
23. 51*
___
___
— —
*£ water volumes sampled/E operating times on days when unit was sampled.
**Calculated from COD using BOD/COD = 0.72.
***Calculated by summing components.
-------
and phosphorus were available for effective biological treatment.
The discussion of water consumption, above, deliberately excluded two
solid waste fluming systems, the shell flume of plant no. 2 and the
butchering flume of plant no. 3. This was done because the authors
believe such large water users to be vestiges of earlier days and not
representative of the majority of today's modern plants nor, certainly,
those of the future.
Except for those plants which flume their butchering waste (a practice
not recommended), the only wastewater flow from the butchering area
is wash-down water. As shown on Table 2, only about ten percent or
less of the total for each parameter was generated in this area.
Two tables appear for the bleeding area. This is because two waste
streams originated there in plant no. 1. The first was the overflow
from the rinse tank (Table 3); the second, the once-per-shift purging
of the tank ("dump"—Table U). Although 13 percent of the total plant
COD was generated there (overflow plus dump), the process was not a
major waste source.
The cookers were the second-most-important waste source. Table 5
presents data from the section cooker and Table 6, the data from the
whole cooker. The whole cooker used more water per ton of crab and
generated much more COD on a tonnage basis. These values (Table 6)
are misleading, however, because the whole cooker throughput was much
lower than that of the section cooker. Since cooking water COD
concentration was a. function of crab throughput and since dumping
schedules were fairly constant, it is not surprising that the whole
cooker COD level (on a production basis) appears to be so much higher
than its section cooker counterpart.
Ignoring, temporarily, the contributions from the whole cooker for
reasons discussed above, one notes (Table 5) that the section cooker was
the major source of ammonia and the "number two" source of COD,
suspended solids and total nitrogen in plant no. 1. Inspection of
Tables 15 and 25 in the Appendix indicates general agreement with this
finding. All samples, incidently, were pre-screened at 20 mesh prior
to analysis.
The tremendous whole cooker total solids level indicated on Table 6
was due mainly to the NaCl added to the unit, as was discussed in
"The Dungeness Crab Process" section. The fact that only 1.3 Ib/T
of 287 Ib/T total solids were retainable on glass fiber filters supports
this contention.
The cooling tank (Tables 7 and 8) was a major water user (30$) "but
contributed little to the total COD, solids or nutrient loads.
453
-------
Likevise the picking area clean-up waters (Table 9) were not major
offenders.
The major offender in the Dungeness crab plant, in terms of water
pollution potential, was the brining step. The brine tank discharge
of plant no. 1 (Table 10) was the major contributor of COD, total
solids (mainly salt), suspended solids (after 20-mesh screening),
total nitrogen and total phosphorus. With the initial samples the
high salt level (particularly chloride) in the brine created
interferences with some of the tests, but these were soon overcome
and the program successfully conducted. Mercuric sulfate was used
to counteract chloride interference in the COD analysis.
The influence of the brine tank was reflected in the brine rinsewater
characteristics (Table 11). Total phosphorus was especially high,
being second only to the brine, itself.
CONCLUSIONS
The results of this study (plant no. 1 only) are summarized on Figures
2 through 6.
Based on the data from the three plants monitored, it appears that
the process-by-process breakdown of wastewater flows and constituents
is fairly consistent from plant-to-plant, at least within the
production range studied (0-10 tons/shift).
Some plants flume solid wastes. This is not necessary. Almost
invariably they screen the flume water prior to discharge. Replacement
of flumes with dry capture systems would significantly reduce the
total plant waste load and is strongly recommended.
In the processing of Dungeness crab the major waste contributors are
the cooking and brining operations. At some time in the future
segregation and separate treatment of these streams may be advisable.
Furthermore, alternatives to brining may be available(6). Elimination
of the brining step would greatly reduce the pollutional impact of the
industry.
ACKNOWLEDGMENTS
The following staff members of the O.S.U. Department of Food Science
and Technology were instrumental in the preparation of this paper
through sample collection, laboratory analysis, data interpretation,
or manuscript review and their participation is gratefully acknowledged:
W. D. Davidson, R. 0. Sinnhuber, J. S. Lee, C. Phillips, C. Neshyba,
R. Cain, S. Pierce, L. Grande, W. Parks, E. Brineman, M. Fitzsimmons
and P. Butz. Furthermore, this study could not have been undertaken
without the willing cooperation of the personnel of the participating
plants, which the authors sincerely appreciate.
454
-------
70OO
6000
5000
4000
3OOO
20OO
1000
LEGEND
0± I STD. DEVIATION
D±2 STD. DEVIATIONS
0 RANGE
Ul
I
a:
o
at
a
OB
o
E
CD
Q
UJ
UJ
O
o
o
o
o
o
o
o
o
o.
z
to
ffl
o
o
Figure 2. Wastewater Volume Summary
455
-------
45
40
35
30
25
Q
O
O
20
15
10
LEGEND
0± I STD. DEVIATION
D±2 STD. DEVIATIONS
III RANGE
ui
Of
O
en
UJ
UJ
a:
o
o
UJ r— i
^
Jk
w rSi
K P
0 £J
B B
(il
UI
h-
Ul
1
I
O
i
|Bj Q j=j ,_,
UJ
o
CO
Q
UJ
UJ
_J
m
o
o
o
o
e>
O
o
o
o
S
o
a.
a:
m
to
z
(C
o
UI
5
o
o
Figure 3. Chemical Oxygen Demand Summary
456
-------
p
>*
£
07
O
0
0)
_1
<
1-
240
220
200
180
160
140
120
100
80
60
40
20
LEGEND
|§± 1 STD. DEVIATION
D±2 STD. DEVIATIONS
0] RANGE
tii
uj u
1- OC UJ
U O (_
1 5 *
u
u
or
u
w
(O
H ±
ffl
e>
z
or
UJ
o
z
o
UJ
OQ
O
o
o
o
z
_l
o
o
o
o to o Q
z z z w
5 z w ?
S2 o: z eg
o. CQ or 2
**- o
o
m
Figure h. Total Solids Summary
457
-------
0.5
0.4
0.3
co
CO
2
a.
0.2
0.1
LEGEND
I2±l STD.
D±2 STD.
DEVIATION
DEVIATIONS
Q RANGE
Ul
^~
Ul
oc
o
(A
u
^
u
CE
U
CO
o
~
^
o
E
111
V
U.
h-
U
o
@Q
V
^
O O
Z Z
t-
y|
„
O
o 2 -i
Ul O O
3 p o
u
v^
i
s
i
s
Q.
c
jj
S
^
^
^
|
^
S
3
0
E
m
F
^
\
s
v>
z
a:
•
'
o
Ul
i
u
Figure 5. Total Phosphorus Summary
458
-------
5.5
5.0
4.5
4,0
P
^
J3
z 35
UJ
0
IT
t 3.0
z
_l
wJ
H
o 2.5
2.0
1.5
1.0
0.5
LEGEND
_
£|± 1 STD. DEVIATION
D±2 STD. DEVIATIONS
(3 RANGE
UI
UJ
-------
APPENDIX
460
-------
Table 12. Combined Wastewater Characteristics
Plant No. 2
Without Shell Flume
With Shell Flume
P_arameter
Flow (gpm)*
(gpT)
COD
BOD**
Total Solids (lb/T)
Settleable Solids (ral/1)
Suspended Solids (lb/T)
Volatile Solids (%)
Total Nitrogen*** (lb/T)
NO^ (lb-N/T)
N0§ (lb-N/T)
NH3 (lb-N/T)
Organic H (lb/T)
Total Phosphorus (lb/T)
Ortho-P0§ (Ib-P/T)
Inorganic P (lb/T)
Total Soluble P (lb/T)
Dissolved Oxygen (ing/l)
Temperature
Mean
5100.39
22.08
13.916
286. U5
92.07
5-11
59.9
3.04619
0.00962
0.000077
0.1507
2.8858
0.3774
0.18U5
0.2474
0.2948
7.3
10.2
5-72
Rang*
—__
6.9-8
11.23-1!
4.27-8
Mean
9126.36
27.16
17-316
295-95
92.37
6.17
65.6
3-58956
0.01802
0.000077
0.1796'
3.5535
0.4996
0.3187
0.3903
7-3
Range
*Total volume/total time during periods when operation was sampled.
**Calculated from COD using BOD/COD = 0.6l.
***Calculated by summing components.
-------
Table 13. Butchering:
Parameter
Flow (gpm)*
(gpT)
COD (lb/T)
BOD** (lb/T)
Total Solids (lb/T)
Settleable Solids (ml/1)
Suspended Solids (lb/T)
Volatile Solids (%)
Total Nitrogen*** (lb/T)
N03 (lb-N/T)
N02 (lb-N/T)
NH3 (lb-N/T)
Organic N (lb/T)
Total Phosporus (lb/T)
Ortho-P0| (ib-P/T)
Inorganic P (lb/T)
Total Soluble P (lb/T)
pH
Dissolved Oxygen (mg/l)
Temperature ( °C )
Cooking Area Washwater
Mean
37-0 (0.583 hr)
225.09
0.79
0.1*66
1.11
2.5
0.31
66.1*
0.07820
0.0005
0.0000
0.0000
0.0777
0.011*1
0.0083
0.0091*
0.0113
7.6
12.2
U.5
Characteristics Plant No. 2 (l sample)
% of Plant
Total
l*.Ul
3.58
3.35
0.39
—
6.10
11.09
2.57
5-20
0.00
0.00
2.69
3.71*
1*.50
3.80
3.83
—
— —
*Total volume/total time during periods when operation was sampled.
**Calculated from COD using BOC/COD = 0.59-
***Calculated by summing components.
-------
Table lU. Preliminary Rinsing
Parameter
Flow (gpm)*
( spr£ ) j
COD (lb/T)
BOD** (lb/T)
Total Solids (lb/T)
Settleable Solids (ml/l)
Suspended Solids (lb/T)
Volatile Solids (%}
Total Nitrogen*** (lb/T)
NO^ (Ib-N/T)
N03 (lb-H/T)
NH_ (lb-W/T)
Organic N (ib-N/T)
Total Phosporus (lb/T)
Ortho-POF (ib-P/T)
Inorganic P (lb/T)
Total Soluble P (ib/'i1)
PH
Dissolved Oxygen (mg/l)
Temperature (°C)
and Bleeding Wastewater
%
Mean
20.2
[1*75.1*8
2.89
1-71
5-99
0.2
0.58
U2.65
0.26090
0.0025
0.0000
0.0000
0.258U
0.0295
0,0030
0.0071*
0.0209
7.3
11.73
It. 27
Characteristics Plant No. 2 (1 sample)
of Plant
Total
«•••«_
28.93
13.09
12.29
2.09
11-35
8.56
26.00
0.00
0.00
8.95
7-82
1.63
2.99
7.09
____
*Total volume/total time during periods when operation was sampled.
"•Calculated from COD using BOD/COD = 0.59-
***Calculated by summing components.
-------
Table 15. Section Cooker Overflow Characteristics
Parameter
Flow (gpm)*
(gpT)
COD (lb/T)
BOD** (lb/T)
Total Solids (lb/T)
Settleable Solids (ml/1)
Suspended Solids (lb/T)
Volatile Solids (%}
Total Nitrogen*** (lb/T)
NO" (lb-N/T)
NOx (lb-N/T)
NH3 (lb-N/T)
Organic N (lb/T)
Total Phosghorus (lb/T)
Ortho-P05 (Ib-P/T)
Inorganic P (lb/T)
Total Soluble P (lb/11)
PH
Dissolved Oxygen (mg/l)
Temperature (°C)
Mean
1.10
92.8
7.28
5.10
11.09
2.8
1.27
59.13
1.01+912
0.000076
0.000052
0.0982
0.9508
0.07*40
0.0233
O.OU31
O.OM6
8.7
— — -*
Range
^«*^
6.38-8.19
U. 147-5. 73
10.68-11.50
2.1-3.5
1.214-1.31
1.01186-1.08628
0.000067-0.000085
___
0. 0921-0. 10143
0.9197-0.9819
0.06ol4-0.0875
0.0082-0.03814
0.0335-0.0527
0.0369-0.0552
8.6-8.7
— —
Plant No. 2 (2 samples)
Standard
Deviation
a_ n
1.29
0.57
0.99
0.52
1.2U
0.000013
0.0086
o.oitUo
0.0192
0.02114
0.0136
0.0110
~»^«~
% of Plant
Total
^^•«
1.82
32.97
36.65
3.87
—
214.85
3l4.l4l4
0.79
67.53
65.16
2.56
19.61
12.63
17-^2
15-13
•»<•»••
*Total volume/total time during periods when operation was sampled,
**Calculated from COD using BOD/COD = 0.70.
***Calculated by summing components.
-------
Ln
Table 16. Cooling Tank
Parameter
Flow (gpm)*
(gpT)
COD (lb/T)
BOD** (lb/T)
Total Solids (Ib/Tj
Settleable Solids (ml/l)
Suspended Solids (lb/T)
Volatile Solids (%)
Total Nitrogen*** (lb/T)
NOo (lb-N/T)
NOg (lb-N/T)
NH3 (lb-N/T)
Organic N (lb/T)
Total Phosphorus (lb/T)
Ortho-POjj (Ib-P/T)
Inorganic P (lb/T)
Total Soluble P (lb/T)
PH
Dissolved Oxygen (mg/l)
Temperature ( °C )
Overflow Characteristics
Mean
18.5
1351.30
1.06
0.53
1.81
0.3
0.2U
69.55
0.116U
0.0028
0.0000
0.0000
0.1138
0.0282
0.0153
0.0192
0.0192
7.0
— ._.
Plant No. 2 (1 sample)
% of Plant
Total
rm .. t t
26.1*9
U.8
3.8l
0.63
— _
U.70
—
3.82
29.11
o.oo
0.00
3.9^
7-^7
8.29
7-76
6.51
"•— '
*Total volume/total time during periods when operation was sampled.
**Calculated from COD using BOD/COD = 0.50.
***Calculated by summing components.
-------
Table 17. Picking Area Washwater Characteristics Plant No. 2 (k samples)
Parameter
Flow (gpm)*
(gpT)
COD (lb/T)
BOD** (lb/T)
Total Solids (lb/T)
Settleable Solids (ml/1)
Suspended Solids (lb/T)
Volatile Solids (%)
Total Nitrogen*** (lb/T)
N03 (Ib-N/T)
NOg (Ib-N/T)
NH3 (Ib-N/T)
Organic N (lb/T)
Total Phosphorus (lb/T)
Ortho-P0| (Ib-P/T)
Inorganic P (lb/T)
Total Soluble P (lb/T)
PH
Dissolved Oxygen (mg/1)
Temperature (°C)
Mean
30.3U fo.U
256.23
1.19
0.67
3.97
2.3
0.38
31.71*
0.1571
0.0005
0.000
0.0038
0.1528
0.0221
0.011*9
0.0169
0.019^
8.0
12.37
8.3
Range
2 hr) 21*. 7-1*2. 8
—
0.97-1.57
0. 5U-0.88
2.62-5.1*2
1.1-3.5
0.29-0.1*7
18.65-37.15
0.1282-0.221*8
0.0003-0.0007
— _
0.0026-0.0081*
0.1253-0.2157
0.0193-0.0257
O.OlUl-0.015U
0.015l*-0.0178
0.0l8**-0.0210
7.7-8.1
12.1-12.5
7-0-12.2
Standard
Deviation
8.39
62.70
0.28
1.29
1.0
0.07
8.76
0.0002
0.0035
0.01*22
0.0033
0.0006
0.0013
0 . 001 1*
0.23
2.60
% of Plant
Total
5-02
5-39
U.81
1.39
_ —
7.1*4
—
5.16
5-20
0.00
2.52
5.29
5.86
8.08
6.83
6.58
—
—
— —
*Total volume/total time during periods when operation was sampled.
**Calculated from COD using BOD/COD = 0.56.
***Calculated by summing components.
-------
Table 18. Crab Shell
Parameter
Flow (gpm)*
(gpT)
COD (lb/T)
BOD** (lb/T)
Total Solids (lb/T)
Settleable Solids '(ml/1)
Suspended Solids (lb/T)
Volatile Solids (%)
Total Nitrogen*** (lb/T)
N03 (lb-N/T)
NOg (lb-N/T)
HH3 (lb-N/T)
Organic N (lb/T)
Total Phosphorus (lb/T)
Ortho-POjj (Ib-P/T)
Inorganic P (lb/T)
Total Soluble P (lb/T)
pH
Dissolved Oxygen (mg/l)
Temperature (°C)
Flume Water
Mean
31.40
4025-95
5.08
3.40
9-50
0.3
1.06
56.82
0.7052
0.0084
0.0000
0.0291
0.6677
0.1222
0.0629
0.0763
0.0955
7.3
12.02
6.86
Characteristics Plant
R_ange_
23.4-37.1
3.57-6.37
2.39-4.27
4.60-12.00
0.2-0.4
0.78-1.39
53 ..8-61. 85
0.31570-0.9936
0.0038-0.0131
0.0000-0.0415
0.3119-0.9390
0.0742-0.1595
0.0418-0.0889
0.0501-0.1111
0.0501-0.1185
7.2-7.9
11.3-12.6
4.9-9-5
No. 2 (4 samples)
Standard
Deviation
6.27
1850.62
1.15
—
4.23
0.12
0.27
4.39
0.0039
_--
0.0197
0.2607
0.0392
0.0233
0.0272
0.0309
__ ._
0.45
1.93
% of Plant
Total ****
44.13
18.70
19.64
3.21
___.
17-18
___
19.65
46.63
0.00
16.30
18.79
24.46
25-42
23.94
24.47
—
—
___
*Total volume/total time during periods when operation was sampled.
**Calculated from COD using BOS/COD = 0.67-
***Calculated by summing components.
****These percentages include the shell flume with the other unit processes to comprise the total
plant discharge.
-------
Table 19. Brine Tank Discrete Discharge Characteristics Plant No. 2 (k samples)
Parameter
Flow (gpm)*
(gpT)
COD (ib/T)
BOD** (ib/T)
Total Solids (lb/T)
Settleable Solids (ml/l)
Suspended Solids (lb/T)
Volatile Solids (%)
Total Nitrogen*** (lb/T)
NOo (ib-N/T)
NO| (lb-N/T)
£ NH3 (lb-N/T)
00 Organic N (lb/T)
Total Phosphorus (lb/T)
Ortho-P0| (ib-P/T)
Inorganic P (lb/T)
Total Soluble P (lb/T)
PH
Dissolved Oxygen (mg/l)
Temperature ( °C )
Mean
0.88
96.9
5-0
2.65
193.91*
83.3
1.75
18.7
0.80916
o.ooooU
0.000025
0.0260
0.7831
0.1092
0.01*56
0.061*2
0.0850
7.5
11.32
7.89
Range
...
— _
1*. 22-5. 69
2.2l*-3.02
155.66-2U3.1*7
70-95
1.20-2.21
l*.81*-33.6
0.63612-0.95662
0.00000-0.00009
0.00002-0.00003
0.0185-0.0356
0.6176-0*9209
0. 0818-0. 1631*
0. 037 1*-0. 0567
0.05Q1+-0.1016
0.0818-0.0921
7-3-7.7
...
5.0-11.8
Standard
Deviation
...
...
0.69
U3.00
12.6
0.1*2
16.0
0.00003
0.000007
0.0083
0.1535
0.0372
0.0082
0.0250
O.OOU8
0.28
2.71*
% of Plant
Total
1.90
22.61*
19.01*
67.70
...
31*. 25
_..
26.56
0.1*15
32.1*7
17.25
27. ll*
28.93
2l*.72
25-95
28.83
— .
.•——
*Total volume/total time during periods when operation was sampled,
**Calculated from COD using BOD/COD = 0.53.
***Calculated by summing components.
-------
Table 20. Primary Brine Rinsewater Characteristics
Parameter
Flow (gpm)*
(gpT)
COD (lb/T)
BOD** (lb/T)
Total Solids (lb/T)
Settleable Solids (ml/l)
Suspended Solids (lb/T)
Volatile Solids (%}
Total Nitrogen*** (lb/T)
NO- (lb-N/T)
N0£ (lb-N/T)
NH3 (lb-N/T)
Organic M (lb/T)
Total Phosphorus (lb/T)
Ortho-PO^ (Ib-P/T)
Inorganic P (lb/T)
Total Soluble P (lb/T)
pH
Dissolved Oxygen (mg/l)
Temperature ( °C )
Mean
6.U8
806.26
1.82
1.31
1*9.38
0.37
0.38
3.33
0.231*80
0.0016
0.0000
0.0115
0.2217
O.OU29
0.031*3
0.0371+
0.01*20
6.9
12.03
6.60
Range
5.1-9.1
_—
1.19-2.12
0.86-1.53
30.93-77-30
0.3-0.5
0.30-0.52
2.8-3.9
0.161*10-0.26930
0.0008-0.0023
0.0029-0.011*7
0.160U-0.2523
0.0339-0.0585
0.0222-0.01*72
0.021*7-0.01*99
0.0333-0.01*79
6.8-7.1
—
-*— —
Plant No. 2
Standard
Deviation
1.76
297.98
0.1*3
— _
19-98
0-12
0.10
0.1*8
0.0006
0.0075
0.01*17
0.0135
0.0128
0.0132
0.0077
0.29
2.16
(1* samples)
% of
Total
50.63
50.31
1*7.03
1*6.95
72.05
65-52
1*0.83
50.00
0.00
50.66
1*0.37
1*2.77
1*6.29
1*5-50
1*5.1*9
•- *~
% of Plant
Total
15.81
8.2U
9.1*1
17- 2U
— „
7.1*1*
_ —
7.71
16.63
0.00
7.63
7.68
11.37
18.59
15.12
lfc.25
«M —
*Total volume/total time during periods when operation was sampled.
**Calculated from COD using BOD/COD = 0.72.
***Calculated by summing components.
-------
Table 21. Secondary
Parameter
Flow (gpm)*
(gpT)
COD (lb/T)
BOD** (lb/T)
Total Solids (lb/T)
Settleable Solids (ml/I)
Suspended Solids (lb/T)
Volatile Solids (%)
Total Nitrogen*** (lb/T)
NOo (Ib-N/T)
NOg (lb-U/T)
Nil- (Ib-N/T)
Organic W (lb/T)
Total Phosphorus (lb/T)
Ortho-P0| (Ib-P/T)
Inorganic P (lb/T)
Total Soluble P (lb/T)
pH
Dissolved Oxygen (nig /I)
Temperature (°C)
Brine Rinsewater
Mean
6.32
796.33
2.05
1.U8
19.16
0.3
0.20
12.83
0.3U03 0.
0.0016 0
0.0000
0.0112 0
0.3275 o
0.0571* 0
0.0398 0
0.01+U8 0
0.052U 0
7.1
12.00
6.69
Characteristics
Range
5.33-7-53
1.80-2.23
1.30-1.61
15.28-25.76
O.l'-O.l*
0.17-0.21
10.9-13.5
26910-0.140570
.0007-0.0026
.0065-0.0153
.2619-0.3878
.01497-0.0757
.0335-0.0550
.0390-0.0616
.0460-0.0678
7.1-7.2
5.0-10.0
Plant Ho. 2
Standard
Deviation
0.90
3^8-. 11
0.18
— -
14.7!*
0.153
0.02
l.ll*
___.
0.0008
_ —
0.0036
0.0516
0.0123
0.0103
0.0112
o.oiou
0.33
2.02
(U samples)
% of
Total
^9-37
1+9.69
52.97
53.05
27.95
3!*. 1*8
—
59.17
50.00
0.00
^9.3^
59.63
57.23
53.71
55.50
55-51
—
- —
— — —
% of Plant
Total
15-63
9.28
10.61+
6.69
—
2.11*
__—
11.17
16.63
o.oo
7.^3
11.35
15-21
21.57
18.11
17.77
—
— -
— —
*Total volume/total time during periods when operation was sampled.
**Calculated from COD using BOD/COD = 0.72.
***Calculated by summing components.
-------
Table 22. Combined Wastewater Characteristics
Plant Wo. 3
Parameter
Without Butchering
Flume
Mean
With Butchering
Flume
Mean
Flow (gpm)*
(gpT)
COD (ib/T)
BOD** (Ib/T)
Total Solids (ib/T)
Settleable Solids (ral/l)
Suspended Solids (Ib/T)
Volatile Solids (%}
Total Nitrogen*** (lb/T)
NOo (lb-N/T)
NOg (lb-N/T)
NH3 (lb-N/T)
Organic » (lb/T)
Total Phosphorus (lb/T)
Ortho-P0| (ib-P/T)
Inorganic P (lb/T)
Total Soluble P (lb/T)
PH
Dissolved Oxygen (ing/l)
Temperature ( °C )
5010.8
33.02
21.3
132,60
703.6
5.T6
17.9
If. 2375
0.0076
0.00062
0.21*37
3.9856
0.1*285
0.1758
0.2781
0.3600
7-7
~~ — ~- •
U216. 9-5989. 6
25.8^-39-02
17.0-20.06
89.^9-181.26
609-6-8U1.7
3.9^-8.13
.15.8-21.0
3.16752-5.11102
0.0056^-0.00939
0. 00038-0. 0066U
0. 1573-0. 31^6
3.000li-^.7&08
0.3222-0.57^6
0.120U-0.25^5
0.213U-0. 3^26
o. 2586-0. 1*876
7-2-8.3
-•""•""
...
621*1*. 3
38.96
25.32
11*0.76
7H.7
6.23
23.5
k. 7911*0
0.0086
0.00072
0.2638
1*.5132
0.1*625
0.1876
0.3007
0.3871*
7.6
" — ' "™
___
51+50.1*3-7223.13
30.1*0-1*7-16
25.00-30.1*5
95.8^-190.02
609.8-81*2.0
l*.2l*-8.88
21.1-26.6
3.505b2-b.9H62
0.006ll*-0. 01069
0.00038-0.00661*
0.1650-0.3506
3.3303-5.51*37
0.31*62-0.6273
0.1236-0.2719
0.233l*-0.3678
0.2758-0.5280
•-— •- •
*Total volume/total time during periods when operation was sampled.
**Calculated from COD using BOD/COD = 0.69.
***Calculated by summing components.
-------
Table 23. Cooling and Preliminary
Parameter
Flow (gpm)*
(gp'i1)
COD (lb/T)
BOD** (lb/T)
Total Solids (lb/T)
Settleable Solids (ml/1)
Suspended Solids (lb/T)
Volatile Solids (%)
Total Nitrogen*** (lb/T)
NOo (ib^-K/T)
NO- (Ib-N/T)
NIC (ib-H/T)
Organic N (lb/T)
Total Phosphorus (lb/T)
Ortho-POjj (ib-P/T)
Inorganic P (lb/T)
Total Soluble P (lb/T)
PH
Dissolved Oxygen (mg/l)
Temperature ( °C )
Mean
58.0
3163.0
10.99
8.13
2l*.51
0.3
l.OU
— —
1.1570
0.0051
o.oooi*
0.0519
1.0996
0.0775
0.021*5
0.01*57
0.06U3
7.6
11.80
8.02
Rinsewater Characteristics
Range
50.3-71-0
2659.9-3811.0
10.1*0-11.65
7.70-8.62
ll*. 80-1*3. 70
0.1-0.5
0.68-1.55
_ __
1.1079-1.1986
0.0038-0.0063
0.0003-0.0005
0.0356-0.0705
1.0682-1.1213
0.0755-0.0795
0.0171-0.0305
o.oi*oi*-o. 051*0
0.0516-0.0776
7-5-7.9
11.33-12.10
5-1*3-10.00
Plant No.
Standard
Deviation
589.1
0.63
__._
16.62
0.2
0.1*6
— _.—
—
0.0018
0.0001
0.0176
0.0278
0.0020
0.0068
0.0073
0.0130
0.1*1
2.35
3 (3 samples)
% of Plant
Total
63.12
33.28
38.10
18.1*8
— __
18.06
.__
27.30
67-11
61*. 52
21.30
27.59
18.09
13.91*
16.1*3
17.86
—
___
—
*Total volume/total time during periods when operation was sampled.
* Calculated from COD using BOD/COD = 0.7 It.
***Calculated by summing components.
-------
-J
CO
Table 2U. Butchering
Parameter
Flow (gpra)*
(gpT)
COD (ib/T)
BOD**(lb/T)
Total Solids (ib/T)
Settleable Solids (ml/1)
Suspended Solids (lb/T)
Volatile Solids (%)
Total Nitrogen*** (lb/T)
NOo (ib-N/T)
NOg- (lb-N/T)
NH_ (lb-N/T)
Organic N (lb/T)
Total Phosphorus (lb/T)
Ortho-POF (ib-P/T)
Inorganic P (lb/T)
Total Soluble P (lb/T)
pH
Dissolved Oxygen (mg/l)
Temperature (°C)
Flume Wastewater
Mean
21.65
1233-53
5.9U
3.98
8.16
0.2
0.1*7
55-6
0.5^88
0.0010
0.0001
0.0201
0.5276
Q.03hO
0.0118
0.0226
0.027**
7-3
12.30
6.01
Characteristics
Range
__„
1*. 56-8. 11*
3.06-5.^5
6.35-10.76
0.2-0.3
0.30-0.70
52.5-55.9
0.33810-0.8006
0.0005-0.0015
0.0000-0.0002
0.0077-0.0360
0.3299-0.7629
0.02UO-0.0527
0. 0032-0. Ollh
0.0200-0.0252
o. 0172-0. okoh
7.3-7-1*
12. 03-12. 1*3
3.97-7-90
Plant No. 3 (3
Standard
Deviation
3-19
1*91. 8U
1.93
—
2.31
0.05
0.23
2.96
0.0007
0.0001
0.011*5
0.2189
0 . 0162
0.0072
0.0037
0.0119
0.23
1.97
samples )
% of Plant
Total
19-75
15-25
15-72
5.80
7.51*
—
11.1*5
11.63
13.89
7-62
11.69
7.35
6.29
7.52
7-07
—
*Total volume/total time during periods when operation was sampled.
**Calculated from COD using BOD/COD = 0.67-
***Calculated by summing components.
-------
Table 25. Cooking Water Characteristics Plant Wo. 3
Parameter
Flov (gpm)*
(gpT)
COD (Ib/T)
BOD** (Ib/T)
Total Solids (Ib/T)
Settleable Solids (ml/1)
Suspended Solids (Ib/T)
Volatile Solids (%)
Total Nitrogen*** (Ib/T)
WOo (ib-N/T)
NOg (lb-N/T)
NH3 (lb-N/T)
Organic N (Ib/T)
Total Phosphorus (Ib/T)
Ortho-POr (ib-P/T)
Inorganic P (Ib/T)
Total Soluble P (Ib/T)
pH
Dissolved Oxygen (mg/1)
Temperature ( °C )
Mean
• H
lib. 7
6.75
U.52
12.1*5
12.5
0.85
58.6
1 . 0817
0.00012
0 . 0001
0.1061*
0.9751
0.0762
0.0172
0.01*35
0.0598
8.5
.._«
Range
•••_.
__-
i*.2U-9.15
2. 84-6.13
7-39-15.^9
U.5-2U.O
O.U3-1.07
56.5-61.1
0.56672-l.U5lt8
o.ooooU-o. 00019
0.00008-0.00012
0.051*1-0.1362
0.5125-1.3183
0.0385-0.1107
0.0018-0.01*38
0.0237-0.0572
0.0218-0.1107
8.2-8.8
(3 samples)
Standard
Deviation
^^ ^
— _
2.1*6
1*.1*1
10.2
0.36
2.32
0.00011
0.00003
0.01*55
0.1*159
0.0362
0.0231
0.0176
o. 01+58
— — —
% of Plant
Total
^^•^
2.37
2Q.kh
21.18
9-3^
lU.76
—
25-53
1.58
16.13
1*3.66
2^.47
17-78
9-78
15.61*
16.61
—
—
___
*Total volume/total time during periods when operation was sampled.
**Calculated from COD using BOD/COD = 0.67-
***Calculated by summing components.
-------
Table 26. Rinse Tank
Parameter
Flow (gpm)*
(gpT)
COD (lb/T)
BOD** (lb/T)
Total Solids (lb/T)
Settleable Solids (ml/l)
Suspended Solids (lb/T)
Volatile Solids (%}
Total Nitrogen*** (lb/T)
N03 (lb-N/T)
NOp (lb-N/T)
NH*3 (lb-N/T)
Organic N (lb/T)
Total Phosphorus (lb/T)
Ortho-POr (ib-P/T)
Inorganic P (lb/T)
Total Soluble P (lb/T)
pH
Dissolved Oxygen (mg/l)
Temperature ( °C )
Overflow Characteristics Plant
Mean
15-2
867.3
U. 50
2.93
29.87
0.9
0.56
20.1*
0.7dQl*5
0.0011
0.00005
0.0305
0.71*88
o.iiUi
0.0790
0.0872
0.1082
7.8
12.27
6.9
Range
ll*.5-15-7
809.0-922.9
3. 76-1*. 96
2.1*l*-3.22
2U. 15-35- 89
0.5-1.2
0.32-0.79
ly.o-21.3
0.721*1*0-0.871*28
0.0008-0.0013
0.00000-0.00008
0.0287-0.0325
0.691*9-0.81*01*
0.1116-0.1181
0.061*6-0.0881
0.0731-0.0978
0.1001-0.1157
7.5-8.1
11.93-12.68
k. 95-8. 7
No. 3 (3 samples)
Standard
Deviation
57-0
0.65
___
5.87
o.i*
0.2U
1.17
0.0003
o.ooooi*
0.0019
0.0797
0.0035
0.0126
0.0127
0.0078
— _
0.38
1.9
% of Plant
Total
17-31
13.63
4-3.73
22.53
9.72
18.1*2
Ik. hi
8.06
12.51
18.79
26.63
hk.yk
31.36
30.05
— — —
*Total volume/total time during periods when operation was sampled,
**Calculated from COD using BOD/COD = 0.65.
***Calculated by summing components.
-------
Table 27. Brine Tank
Parameter
Flow (gpm)*
(gpT)
COD (lb/T)
BOD** (lb/T)
Total Solids (lb/T)
Settleable Solids (ml/I)
Suspended Solids (lb/T)
Volatile Solids (%}
Total Nitrogen*** (lb/T)
NO" (Ib-N/T)
NOp (Ib-N/T)
NHo (Ib-N/T)
Organic K (lb/T)
Total Phosphorus (lb/T)
Ortho-P0| (ib-P/T)
Inorganic P (lb/T)
Total Soluble P (lb/T)
pH
Dissolved Oxygen (mg/l)
Temperature (°C)
Discrete Discharge
Mean
0.53
33.3
5-1*0
2.86
5^.63
680.0
1.86
13.98
0.75061 o
0.0000
0.00001 0
0.021*1*
0.7262
0.081*9
0.0179
0.0503
0.0625
7.1*
9.1*
13.2
Charac t eri st ic s
Ran^e
.._
3.10-6.29
1.61+-3.33
35 . 6U-67 . 1*8
600.0-800.0
1.28-2.76
8.7-28.0
.1*5730-0.9511*2
0.0000-0.0000
.00000-0.00002
0.01143-0.0321*
0.1*1*30-0.9190
0.01*03-0.1759
0.0068-0.01*35
0.0369-0.06&5
0.0322-0.1067
7.1-7-8
9.0-10.1
11.0-15.7
Plant Ho. 3
Standard
Deviation
.__
1-31
_ —
13.02
90.8
0.58
8.02
0.00001
0.0067
0.1807
0.0555
0.0151
0.0137
0.031*1*
0.1*2
1.71
(5 samples)
% of Plant
Total
0.66
16.35
13.1*0
1*1.20
___
32.29
17.71
0.00
1.61
10.01
18.22
19.81
10.18
18.09
17.36
«•« ~v
*Total volume/total time during periods when operation was sampled.
**Calculated from COD using BOD/COD =0.53.
***Calculated by summing components.
-------
Table 28. Butcnering
Parameter
Flow (gpm)*
(gpT)
COD (lb/T)
BOD** (lb/T)
Total Solids (lb/T)
Settleable Solius (ral/l)
Suspended Solids (lb/T)
Volatile Solids (%}
Total Nitrogen*** (lb/T)
iJO^ (ib-U/T)
NOg ( Ib-N/'J )
ifuo (lb-ii/T)
Organic A (lb/T)
Total Phosphorus (lb/T)
Ortho-P0| (lb-P/T)
Inorganic P (lb/T)
Total Soluble P (lb/T)
pii
Dissolved Oxygen (rag/1 )
Temperature (°c)
Area Washwater
Mean
73.7
530.6
2.9!*
1.66
2.88
2.1
0.60
53.7
0.19093
0.0009
0.00003
0.0158
0.17^2
0.0298
0.0133
0.0208
0.0298
7.6
11. V
7.0
Characteristics
Range
59.1*-88.0
1*75.2-586.1
___
___
1.92-3.35
1.0-3-0
0.57-0.62
58.6-58.9
0.11660-0,261425
0.0008-0.0010
0.00000-0.00005
0.0137-0.0178
0.1021-0.21*63
7.6-7-7
11.7-12.2
5-0-9.0
Plant No. 3
Standard
Deviation
20.2
78.1*
1.36
- 1.1*
o.oU
0.21
0.00014
0.000035
0.0029
0.1020
!.
0.35
2.83
(2 samples)
% of Plant
Total
10.59
8.90
7-87
2.17
—
10.1*2
l*-51
11 . yi*
!*• . 81*
6! 1*8
l*.37
6.95
7-57
7.^8
8.26
•X-fp,
volume/total time during periods when operation was samplea.
1 H.t.fiH fvnm f!Pl,l iianv-itr 'KCVi/fTll) = n KT
--
**Calculated from (JOD using BOD/COD = 0-57.
***Calculateti by summing components.
-------
Table 29. Picking Area Washwater
Parameter
Flow (gpm)*
to)
COD (lb/T)
BOD** (lb/T)
Total Solids (lb/T)
Settleable Solids (ml/l)
Suspended Solids (lb/T)
Volatile Solids (J6)
Total Nitrogen*** (lb/T)
tfOo (Ib-N/T)
NO;; (ib-K/T)
NIC (Ib-N/T)
Organic N (lb/T)
Total Phosphorus (lb/T)
Ortho-POr (ibrP/T)
Inorganic P (lb/T)
Total Soluble P (lb/T)
pri
Dissolved Oxygen (mg/l)
Temperature (°C)
Mean
1+8.6
298.0
2.1+1+
1.22
8.26
7.9
0.85
27-16
0.27683
0.0001+
0.00003
0.011+7
0.2617
0.01+60
0.0239
0.0306
0.035^
8.1+
12.1
6.8
Characteristics
Range
26.2-86.5
120.8-517-6
1.1+0-1+.03
0.70-2.02
5.59-1U.85
3.5-13.0
0.1+1-1.39
15.0-1+1.0
0.19080-0.36137
0.0002-0.0006
0.00000-0.00007
0.0109-0.0252
0.1797-0.3355
0.0265-0.0606
0.0168-0.0353
0.0185-0.01+1+3
0.0231-0.01+71
8. 1-8.. 6
11.8-12.1+
6.0-7-5
Plant No. 3
Standard
Deviation
__.
199-1
1.13
1+.1+2
k.2
0.1+3
13.01+
—
0.0002
o.ooooi*
0.0070
0.061+8
0.011+2
0.0801
0.0108
0.0105
0.29
0.75
(1+ samples)
% of Plant
Total
5-95
7.39
5-72
6.23
— __
11+.76
—
6.53
5-26
k.tik
6.03
6-57
10.71+
13.59
11.00
9.63
—
—
—
*Total volume/total time during periods when operation was sampled.
**Calculated from COD using BOD/COD = 0-59
***Calculated by summing components.
-------
REFERENCES
1. SODERQUIST, M. R. , WILLIAMSON, K. J., BLANTON, G. I., JR.,
PHILLIPS, D. C., LAW, D. K. and CRAWFORD, D. L. Current Practice
in Seafoods Processing Waste Treatment. Federal Water Quality
Administration, Washington, D.C. 119 p. (1970).
2. SODERQUIST, M. R. , BLANTON, G. I., JR. and D. W. TAYLOR.
Characterization of Fruit and Vegetable Processing Wastewaters.
Proceedings of the Third National Food Wastes Symposium.
Environmental Protection Agency, Corvallis, Oregon, (in press).
3. SODERQUIST, M. R. and TAYLOR, D. W. Lab on Wheels. Agricultural
Engineering 53(7):13. (1972).
k. DOSTAL, K. A. personal communication. (1971).
5. SAWYER, C. N. Biological Treatment of Sewage and Industrial
Wastes. Vol. 1. (J. McCabe and W. W. Eckenfelder, Jr., eds.).
Reinhold Publishing Co., New York. (1956).
6. LEARSON, R. J., REIERSTAD, G., and AMPOLA, V. G. The Application
of Continuous Centrifugation to Seafood Processing. Food
Technology 26(7):22. (1972).
479
-------
SUMMARY: FOOD WASTE RESEARCH—WHERE DO WE GO FROM HERE?
by
Dale A. Carlson*
During the past three days of a very fine conference, we have listened to
reviews of nearly twenty types of food processing waste characteristics,
looked at a number of process modifications, and heard of a dozen treatment
methods applied to the food processing industry. At this point, the question
becomes one of relating all the information obtained to some integrated body
of knowledge that can be applied to our daily waste treatment problems in
the year ahead. As well, the information needs to be used to provide for our
national needs, to enhance industrial productivity, and, at the same time,
preserve our natural life systems as we know them. And, finally, in assess-
ment, we need to establish the goals for the 1973 Symposium.
Some of the papers presented were critical of present processing and treatment
methods, some reviewed stream qualities and handling methods for wastes, some
noted that earlier processing methods, with modification, could be more efficient
than those in use today. Other speakers discussed various process changes and
covered possible future regulations at the Federal level.
Typical examples of the papers include Stone's discussion of a process change
to provide dry caustic peeling for peaches which reduced the pounds per day
of organic matter discharged from the process and thereby reduced the pollution
load. But also, the process was less abusive to the fruit, lowered operating
costs, and reduced fresh water requirements by 90 .percent.
Lund noted that the individual quick blanch reduced effluents from 68 to 99
percent depending on the crop processed. Several authors looked at treatment
processes such as membrane filtration for soy whey treatment. Boyle and
Polkowski evaluated the effectiveness of aerated lagoons for cheese whey
wastes. They found adequate treatment but noted that the waste stream was
nitrogen deficient.
Soderquist, in reporting on an ongoing study, noted that in recent years the
handling of wastes in the West Coast seafood industry has been upgraded while
Claggett reported on the improvement in fish wastes solids removal with
caustic-alum treatment combined with air flotation. He noted that the demon-
stration unit operated better than the pilot unit and that the value of
recovered solids should offset the sum of unit operation and sludge recovery
costs.
*Professor and Chairman, Department of Civil Engineering, University of
Washington, Seattle, Washington 98105.
481
-------
Taylor and Dostal examined the treatability of wheat starch processing
wastes using the anaerobic trickling filter and encouraged further studies
to develop the characteristics of the anaerobic filter as a rugged resilient
treatment unit with removal efficiencies not affected by down times of as
long as 30 days.
Cywin and LaGraff presented previews of HR 11896 mentioning possible levels
for treatment and collection. Also discussed were enforcement activities
including citizen participation and user charges. Continued Federal-State
cooperation was encouraged.
And finally, papers on Friday included discussions of dried cattle rumen
as a useful channel catfish feed and the use of the biodisc in initial
controlled studies on the treatability of potato wastes. With nutrient
addition, Cochrane and Dostal obtained COD removals of 91-95 percent for
potato granules.
Russell discussed secondary treatment and polishing of winery wastes
including the icing problems of aerated lagoons in cold climates while
Schwartz presented a review of biological treatment of brewery wastes and
commented on the treatability problems associated with high BOD loads that
are readily degradable.
The gist of the papers was that the total overall mass balance is being
accepted as a realistic approach to industrial process evaluation. The
diagram shown in Figure 1 notes that for every industrial process the total
of the pounds of raw material (a) plus water (b) plus air (c) entering the
process must equal the total of pounds of product (x), plus by-products (y)
and waste products (z) leaving the system. This simple mass balance says
then that
Ib of "a" + Ib of "b" + Ib of "c" = Ib of "x" + lb of "y" + lb of "z"
Of course, the energy balance can likewise be drawn for the process so that
in Figure 2 the industrial process raw materials, products, waste products,
and energy steps must necessarily develop for all the operations incorporated
in actually providing the product. The center column of Figure 2 lists some
of the aspects of processing that must be considered.
The Figures 1 and 2 apply as well to all of man's construction activities,
and are involved with national economics as well as the entire world system
of commerce and interacting living communities. The intricacies and complex-
ities involved with evaluating the totality of these balances necessitate
not only cooperation and good will between industry, government, and
universities but also world-wide cooperation in environmental quality control,
process innovation, and market development. Perhaps only when proper evalua-
tion of the balances is achieved and the total implications of change in the
processes are understood, can we properly make the proper selection of
alternatives for use of our natural resources.
482
-------
TOTAL
MASS
"M"
TOTAL
MASS
"M"
RAW MATERIALS
ENERGY
AIR
MANUFACTURING
PROCESS
MANPOWER
MACHINERY
SPACE
HOUSING
TRANSPORTATION
PACKAGING
ANALYSES
EVALUATION
CONTROL
PRODUCTS
Bf PRODUCTS
WASTE PRODUCTS
FIGURE 2
TYPICAL MANUFACTURING PROCESS
483
-------
This does not mean, however, that we can wait with improvements until the
entire interlocking system is evaluated. It does mean that we need to be
aware of the enormity of and the perturbation qualities of the balances and
seek to logically evaluate the systems. What will be required are innovative
approaches to remove current roadblocks to further process enhancement. In
environmental control, studies must be continued on alternative approaches
to alleviate environmental degradation. While tertiary and quaternary treat-
ment steps must be a part of the tools available for quality control, process
modification, recycling, and reuse should be considered as prime mechanisms
for diminishing product losses, conserving materials, and reducing production
costs.
Nevertheless, it must be recognized that no single mechanism is apt often
to be the total panacea, and secondly it is obvious that, as a corollary to
the mass balance, it is not possible to use raw materials to construct
anything new in this world without at the same time destroying some other
part of the existing environment. Thirdly, the treatment processes added
to a system to reduce environmental pollution are in themselves processes
which require energy, money, and materials and thereby in their own right
can create environmental pollution problems. Finally, it is quite often
possible that the alleviation of a solid wastes problem will be detrimental
to the water or air environment and vice versa.
Thus, in Figure 3, an idealized theoretical diagram indicates that the
energy and cost requirements can go up as greater and greater removal of
a pollutant is required. In Figure 4, the concomitant pollutions added
to the environment in, say, obtaining manufacturing, processing and trans-
porting chemicals, in providing the energy for chemical addition and then
removing and disposing of the sludge produced may at some point exceed the
amount removed. Other mechanisms could be brought into play for reducing
the waste load which do not have this great an environmental effect. A
number of alternatives exist at this point including combining waste streams
for symbiotic removal opportunities, process modification and renovation,
recycling, and increased quality control.
Beyond the material systems listed above are the needs for industries
to encompass human relations in their attempts to make their processes
compatible with the environment and with man's desires. Not only is it
necessary that the public become aware of industry's efforts to provide
desirable products without undue environmental diruption, but also industry
must provide information and incentives for public endorsement of alternatives
providing feasible solutions to pollution control and public endorsement,
as well, of the additional costs involved in providing those quality products
with corresponding environmental quality control.
The future will require that innovation and incentive are integral mechanisms
in maintaining national and industrial well being in the face of world
economic and marketing difficulties. As unacceptable employment levels,
inflationary spirals with concomitant lack of adequate increases in productivity,
.deteriorating trade balances, and gradual erosion of the position of the
United States in international technological competition combine with
484
-------
Figure 3
EFFECT OF POLLUTION CONTROL
ON ENERGY CONSUMPTION
100
Figure shows idealized smoothed curves for
descriptive purposes only. Curve shapes and
crossover points will vary significantly in
individual situations.
POLLUTANT
CONCENTRATION
00
ENERGY USED
IN TREATMENT
NATURAL
PURIFICATION
PRIMARY
SECONDARY
TERTIARY
QUATERNARY
-------
Figure 4
100
75
POLLUTANT
CONCENTRATION
50
25
\
\
\
EFFECT OF POLLUTION CONTROL
ON ENVIRONMENTAL POLLUTANTS
Note: Figure shows idealized smoothed curves for
descriptive purposes only. Curve shapes and
crossover points will vary significantly in
individual situations.
\
\
\
\
\
\
\
•\
\
\
\
POLLUTANTS
ADDED BACK TO
THE ENVIRONMENT
NATURAL ' PRIMARY
PURIFICATION ™""A1"
SECONDARY
TERTIARY
QUATERNARY
-------
the unresolved problems of our society and the resolution of authority
to force ever greater stresses on American leadership, it becomes daily
more necessary for all of us, regardless of American heterogeneity problems,
to strive toward solving our environmental quandaries as a team.
When economic progress is measured by ever expanding gross national product,
there is a necessity for a continuous search for raw materials, empirical
development of new materials and devices, maximizing of available labor
and the availability of investment capital. To these activities must now
be added: (1) the recognition of the limits to our natural resources and
the limits to receptor capacities for wastes; (2) the need for disciplined
use of our intellectual powers in understanding nature both for using its
benefits and preserving its integrity; (3) recognition of the abilities of
other nations to produce as well as or better than the United States, and
thereby recognition of the need to learn from others, to observe and
appreciate their culture as well as their techniques and thereby develop
products to fit their culture, i.e. there is a developing need to amalgamate
to a greater extent with world wants.
In order that we maintain both cultural and industrial viability in the
future, it must now be evident that increasing GNP is not a sufficient
goal in itself, but rather that industry, government, lay population, and
universities coordinate their efforts to innovate, invent, and employ
technology and philosophies which can provide the goals for men to strive
for as responsible citizens of the country and the earth. This means that
significant income fractions need to be relegated to both technological and
sociological research to provide incentives for mankind, to identify blockages
in our present system, and to enhance our current sociological and industrial
systems. Finally, the need to accept philosophies that recognize quality in
both product and work habits are of prime importance in maintaining a quality
environment together with industrial and community well being.
As stated by Boydston, the Symposium goals are to provide an early forum
for presenting the latest research in the food processing industry. In
seeking greater international coverage of work on recycle, reuse, higher
forms of treatment, and process improvement, the Symposium will be even
more valuable in the years to come, and we look forward with interest to
next year's papers. We trust that all of you will be promoting the development
of another excellent set of presentations.
487
-------
REGISTRATION LIST
DONALD A. ADAMS
McFarland-Johnson-Gibbons
333 Front Street
Binghamton, NY 13905
ROGER L. ADAMS
Northwest Paper Company
Cioquet, MN 55720
WILLIAM H. ADLER
States Illam
New Orleans, LA 70116
0. E. ALBERTSON
Envirotech Systems, Inc.
P. 0. Box 8158
San Francisco, CA 94128
C. HENRY ALLEN
Gerber Products Co.
460 Buffalo Road
Rochester, NY 14602
THOMAS S. ALLEN
Ethyl Corporation
2296 Hollydale Avenue
Baton Rouge, LA 70808
WILLIAM L. AMT
The Carborundum Company
P. 0. Box 1269
Knoxville, TN 37720
GERRY B. ANDEEN
Michigan Technical University
Houghton, MI 49931
TED. R. ARNOLD
Westinghouse Electric Corp.
P. 0. Box 9175
Philadelphia, PA 19113
THEODORE AUCOIN, JR.
Kaiser Aluminum & Chem. Corp.
P. 0. Box 1600
Chalmette, LA 70043
DANIEL W. BAKER
National Marine Fisheries Service
Emerson Avenue
Gloucester, MA 01930
GREGORY J. BARBIER
L. S. U. N. 0.
4622 Orleans
New Orleans, LA 70119
ROY W. BARNS
Triangle E By Products Co.
Harrisonburg, VA 22801
RONALD L. BARROW
E.P.A. - Southeast Water Laboratory
College Station Road
Athens, GA 30601
MARTHA I. BEACH
N.-Con Systems Co., Inc.
410 Boston Post Road
Larchmont, NY 10538
C. W. BEATTY
Stone & Webster Canada Limited
60 Adelaide Street
Toronto, Ontario, Canada
MALCOLM C. BEAVERSTOCK
UNIROYAL
Geismar, LA 70734
EDWARD R. BECK
General Mills, Inc.
9000 Plymouth Avenue, North
Minneapolis, MN 55427
ERNEST W. BECK, JR.
Spreckels Sugar Company
338 Green Oaks Drive
Atherton, CA 94025
H. 0. SENSING
CPC International
4240 N. Northbrook
Peoria, IL 61614
489
-------
J. H. BENTON
Ethyl Corporation
451 Florida
Baton Rouge, LA 70801
FERDINAND BESIK
Ontario Research Foundation
Sheridan Park
Mississauga, Ontario, Canada
ALLEN W. BETZ
Betz Engineering Sales Co.
7979 Earhart Boulevard
New Orleans, LA 70125
EDWARD T. L. BORIE
Walk, Haydel & Associates, Inc.
762 Baronne Street
New Orleans, LA 70113
CRAIG A. BRANDON
Clemson University
Clemson, SC 29631
DAN E. BROOKS
National Canners Association
1600 So. Jackson Street
Seattle, WA 98144
WILLARD R. BROSZ
Green Giant
LeSueur, MN 56058
DONALD R. BROWN
CPC International, Inc.
P. 0. Box 345
Argo, IL 60501
WILLIAM F. BUCHOLZ
PCE, Inc.
3525 So. Causeway Blvd.
Suite 633
Metairie, LA 70002
CLAYTON D. CALLIHAN
Louisiana State University
Chemical Engineering Dept.
Baton Rouge, LA 70803
ROY E. CARAWAN
129' Schaub Hall
North Carolina State Univ.
Raleigh, NC 27607
CLARENCE J. CARLSON
U. S. National Marine Fisheries Serv.
Emerson Avenue
Gloucester, MA 01930
DALE A. CARLSON
201 More Hall
University of Washington
Seattle, WA 98195
DAVID J. CARVILLE
Barnard & Burk, Inc.
P. 0. Box 15648
Baton Rouge, LA 70815
EDWIN A. CATALANO
USDA-ARS
1100 Robert E. Lee Blvd.
New Orleans, LA 70119
ROBERT E. CEROSKY
General Foods Corporation
250 North Street
White Plains, NY 10625
BROOKS D. CHURCH
North Star Research
3100 - 38th Avenue South
Minneapolis, MN 55406
FRED G. CLAGGETT
Fisheries Research Board
6640 N.W. Marine Drive
Vancouver, 8, B.C. Canada
CLIFF H. COLE
Universal Foods Corp.
325 North 27th Street
Milwaukee, WI 53208
JEFF COLLINS
National Marine Fisheries Service
P. 0. Box 1064
Kodiak, AK 99615
NEWTON V. COLSTON
North Carolina State University
Box 5993
Raleigh, NC 27607
RAY S. CORKERN
1900 Robert E. Lee Boulevard
New Orleans, LA 70119
490
-------
EDWIN COX, III
Edwin Cox Associates
P. 0. Box 8025
Richmond, VA 23223
HOMER E. CROTTY
DuBois Chemical Research
3630 E. Kemper Road
Sharonville, OH 45240
R. E. DAUPHINEE
Crane-Env. Systems Division
6300 West Park - Suite 315
Houston, TX 77027
JAMES J. DAVIES
Roy F. Weston, Inc.
7380 Exchange Place
Baton Rouge, LA 70806
CHARLES H. DAVIS
Chas. T. Main, Inc.
1301 E. Morehead
Charlotte, NC 28212
ROGER A. DECAMP
National Canners Association
1600 S. Jackson Street
Seattle, WA 98144
DOMENIC DEFELICE
Beech-Nut, Inc., R&D Div.
460 Park Avenue
New York, NY 10022
JOHN S. DEMURLEY
Envirotech, Inc.
1620 U. S. Route 22
Union, NJ 07083
HARRY E. DERTON
Centrifugal & Mech. Ind.
146 President Street
St. Louis, MO .63118
B. E. DIETZ
1302 South Elm
Champaign, IL 61820
JESS C. DIETZ
Clark, Dietz & Associates
211 North Race Street
Urbana, IL 61801
EARL S. DOBBS
W. S. Nelson & Co., Inc.
1200 St. Charles Avenue
New Orleans, LA 70130
DONALD L. DOWNING
N.Y. State Agriculture Exp.
Cornell University
Geneva, NY 14456
EMIL F. DUL
Engineering Science, Inc.
185 Great Neck Road
Great Neck, NY 11021
ROBERT H. EINARSEN
Triangle E By Products Co.
P. 0. Box 471
Harrisonburg, VA 22801
CRAIG S. EKERMEYER
Brown-Miller Company
P. 0. Box 158
Wiggins, MS 39577
R. D. ELLENDER
Gulf South Research Inst.
P. 0. Box 26500
New Orleans, LA 70126
WILLIAM ELLERS
Dorr Oliver
100 South York
Elmhurst, IL 60126
JIM ELSKEN
Dorr Oliver
Havemeyer Lane
Stamford, CT 06900
PETER M. EMERSON
Economic Research Service
500 - 12th Street, SW
Washington, DC 22150
WILLIAM F. ESCUDERO
Contadina Foods, Inc.
2906 Santa Fe Street
Riverbank, CA 95367
PAUL T. EUBANKS
Arthur G. McKee & Co.
10 So. Riverside Place
Chicago, IL 60606
Sta.
491
-------
PATRICK FALLON
British Embassy
3100 Massachusetts Dr.
Washington, DC 20008
LINWOOD E. FARMER
Tulane University
5220 Camp Street
New Orleans, LA 70115
JOHN W. FARQUHAR
American Frozen Food Institute
919 - 18th Street, N.W.
Washington, DC 20006
W. FLUEHRS
General Foods Corporation
1551 East Willow Street
Kankakee, IL 60901
IRA V. FORDYCE
American Crystal Sugar Co.
Box 357
E. Grand Forks, MN 56721
ROBERT W. FOSTER
E. I. duPont deNemours Co.
Box 1378
Louisville, KY 40201
REGINALD A. GALLOP
Head, Food Science Dept.
University of Manitoba
Winnipeg, Manitoba, Canada R3M OH9
JEAN R. GEISMAN
Ohio State University
2001 Fyffe Ct.
Columbus, OH 43210
LOU C. GILDE
Campbell Soup Company
4119 King Avenue
Pennsauken, NJ 08109
DAVID R. V. GOLDING
Dole Company
Box 3380
Honolulu, HI 96801
JOHN, H. GREEN
WSDC, NOAA, NMFS, FTP LAB
Regents Drive,
College Park, MD 20740
FRANCIS A. GRILLOT
F. C. Schaffer & Associates
185 Bellewood Drive
Baton Rouge, LA 70815
FRANK R. GROVES, JR.
Louisiana State University
1055 West Lakeview Drive
Baton Rouge, LA 70810
R. JAMES GUILBEAUX
Bruce Foods, Inc.
P. 0. Box 1030
New Iberia, LA 70560
C. FRED'GURNHAM
Gurnham & Associates, Inc.
223 West Jackson
Chicago, IL 60606
LEO F. HANEY
Calgon Corporation
P. 0. Box 1346
Pittsburgh, PA 15230
DOUGLAS P. HARRISON
Louisiana State University
Department of Chemical Eng.
Baton Rouge, LA 70803
VERA C. HASLING
USDA - ARS - SMN
1100 Robert E. Lee Boulevard
New Orleans, LA 70119
HARRISON L. HATCH
Carnation Company
5045 Wilshire Boulevard
Los Angeles, CA 90036
RALPH C. HAUZEE
ICI - America
Vol. Army Ammunition Plant
Chattanooga, TN 37401
LEIGH C. HAYES
Amstar Corporation
7417 No. Peters Street
Arabi, LA 70032
ROBERT L. KILLER
Env. Protection Agency
1600 Patterson
Dallas, TX 75201
492
-------
H. H. HINDS
Champlin Petroleum Co.
Fort Worth, TX 76107
FRED C. HOBSON
J. N. Pease Associates
P. 0. Box 12725
Charlotte, NC 28205
JAMES C. IELASE
Archer Daniels Midland
P. 0. Box 1470
Decatur, IL 62525
GILBERT S. JACKSON
Env. Protection Agency
Washington, DC 20460
KARL T. JOHNSON
Env. Protection Agency
Office of Refuse Act Programs
Washington, DC 20460
RICHARD H. JONES
Env. Engineering, Inc.
2324 S.W. 34th Street
Gainesville, FL 32601
ROBERT H. JOOST
Env. Pollution Control
Box 11
Oconomowoc, WI 53066
ALLEN M. KATSUYAMA
National Canners Association
1950 Sixth Street
Berkeley, CA 94710
HAROLD G. KEELER
Env. Protection Agency
Office of Research and Monitoring
Washington, DC 20460
PHILIP J. KELLER
DuPont - Experimental Station
Wilmington, DE 19898
GARY W. KEMPF
Ayres, Lewis, Norris, & May, Inc.
3983 Research Park Drive
Ann Arbor, MI 48104
ROBERT P. KINGSBURY
Ethyl Corporation
451 Florida
Baton Rouge, LA 70815
E. L. KNOEDLER
St. Powell Assoc.
501 St. Paul Street
Baltimore, MD 21202
E. G. KOMINEK
Eimco/Envirotech
Salt Lake City, UT 84110
GEORGE R. KOONCE
Minnesota Pollution Control Agency
717 Delaware Street, S.E.
Minneapolis, MN 55414
WILLIAM J. LACY
Environmental Protection Agency
Xerox Building
Washington, DC 20460
RONALD M. LEACH
Michigan Dept. of Agriculture
Lewis Cross Building
Lansing, MI 48913
PAUL F. LEAVITT
Gerber Products Co.
Fremont, MI 49412
SERGE LESSARD
Quebec Water Board
585 East Charest Blvd.
Quebec, P.Q., Canada
ARTHUR W. LILES
ESSO
Murray Hill, NJ 07974
EDMOND P. LOMASNEY
Environmental Protection Agency
1421 Peachtree St., N.E.
Atlanta, GA 30309
WALTER F. LUEHRS
General Foods Corp.
1551 E. Willow Street
Kankakee, IL 60901
493
-------
DARYL R. LUND
University of Wisconsin
Dept. of Food Science
5 Babcock Hall
Madison, WI 53706
ROGER J. LUTZ
Gerber Products Co.
445 State Street
Fremont, MI 49412
JOHN MACCAGNAN
Beech-Nut, Inc.
460 Park Avenue
New York, NY 10022
STAFFORD J. MACHAS
Quaker Oats Company
Merchandise Mart Place
Chicago, IL 60654
H. MARTIN MAHIN, JR.
ACS Publications
1155 16th Street, NW
Washington, DC 20036
JOSEPH MARKIND
Westinghouse
852 Browning Place
Morristown, NJ 07960
DAVID R. MARSHALL
Shilstone Test Laboratories
814 Conti Street
New Orleans, LA 70112
JAMES C. MARTIN
U. S. Army Corps of Engineers
Fort of Pyrtania
New Orleans, LA 70133
TIM A. MATZKE
Environmental Protection Agency
1600 Patterson
Dallas, TX 75201
A. FRANK MAULDIN
Domingue, Szabo & Assoc.
117 Calco Boulevard
Lafayette, LA 70501
WILLIAM H. McCOMBS
McCombs, Knutson Assoc.
12805 Olson Highway
Minneapolis, MN 55441
JOHN w. MCNEIL
Autotrol Corporation
5855 N. Glen Pk. Road
Milwaukee, WI 53092
ANTHONY V. METZNER
Carborundum
Box 1269
Knoxville, TN 37901
SAMUEL P. MEYERS
Dept. of Food Science
Louisiana State University
Baton Rouge, LA 70803
GAUVIN MICHEL
Quebeck Water Board
585 East Charest Boulevard
Queb ec, P.Q., Canada
JOHN A. MIKES
Lundy Electronics
71 Grace Avenue
Great Neck, NY 11021
VERLIS E. MILLER
National Fruit Prod. Co., Inc.
P. 0. Box 609
Winchester, VA 22601
PAUL MINOR
Environmental Protection Agency
Washington, DC 20460
THOMAS E. MOLE
Quaker Oats, Inc.
Merchandise Mart PI.
Chicago, IL 60654
ARTHUR E. MOLIN
Environmental Protection Agency
100 California Street
San Francisco, CA 94111
494
-------
WILLIAM A. MONGE
Libby, McNeill & Libby
5555 West 115th Street
Worth, IL 60482
A. J. MONTA
Welch Foods, Inc.
#2 South Partage Street
Westfield, NY 14787
PATRICK MOONEY
Louisiana State University
40 Killdeer Street
New Orleans, LA 70124
P. H. MULCAHY
Envirotech Corporation
P. 0. Box 300
Salt Lake City, UT 84110
LEE A. MULKEY
Environmental Protection Agency
Southeast Water Laboratory
College Station Road
Athens, GA 30601
JAMES H. GATES
J. R. Simplet Co.
Box 1059
Caldwell, ID 83605
L. DONALD OCHS
E. I. DuPont
Experimental Station
Wilmington, DE 19898
WILLIAM A. PARSONS
Arthur G. McKee
6200 Oak Tree Boulevard
Cleveland, OH 44131
JAMES R. PATRICK, Jr.
Environmental Protection Agency
1421 Peachtree Street, NE
Atlanta, GA 30309
WAYNE L. PAULSON
University of Iowa
4110 Engineering Building
Iowa City, IA 52240
J. DONALD PAULUS
Whitman Requardt & Assoc.
#2 West Preston Street
Baltimore, MD 21201
EDGAR H. PAVIA
Pavia-Byrne Engineering Corp.
431 Gravier Street
New Orleans, LA 70130
GRANVILLE PERKINS
Artichoke Industires, Inc.
11599 Walsh Street
Castroville, CA 95012
PALMER L. PETERSON
National Marine Fisheries Service
2725 Montlake Boulevard, East
Seattle, WA 98102
JIM T. PETROSKY
Vulcan Materials Co.
P. 0. Box 545
Wichita, KS 67201
RALPH W. PIKE
Louisiana State University
6053 Hibiscus Drive
Baton Rouge, LA 70803
SHELDON B. POLLACK
Amstar Corporation
266 Kent Avenue
Brooklyn, NY 11211
LAWRENCE M. POTTER
VPI & SU
Blacksburg, VA 24061
DAVID M. POXTON
Michigan Dept. of Commerce
Lansing, MI 48901
CARLOS QUIROGA
Pavia-Byrne Eng. Corp.
431 Gravier Street
New Orleans, LA 70130
JACK W. RALLS
National Canners Association
1950 Sixth Street
Berkeley, CA 94710
DUANE H. RASMUSSEN
Jacobs Engineering Company
837 South Fair Oaks Avenue
Pasadena, CA 91105
495
-------
A. P. REDOVNIKOVICH
U. S. Army Corps of Engineers
805 Oaklawn Drive
Metairie, LA 70005
AUSTIN RHOADS
American Frozen Foods Institute
919 - 18th Street, NW
Washington, DC 20006
JOE G. RICHARD, JR.
Ethyl Corporation
451 Florida Street
Baton Rouge, LA 70801
ALLYN RICHARDSON
Environmental Protection Agency
2303 J. F. Kennedy Building
Boston, MA 02203
H. S. RITTER
PPG Industries, Chemical Div.
Columbia Center
Barberton, OH 44203
CHRIS D. ROBERTS
Contadina Foods, Inc.
P. 0. Box 29
Woodland, CA 95695
CHARLES S. ROGERS
Environmental Protection Agency
Solid Waste Research Division
5555 Ridge Avenue
Cincinnati, OH 45213
WALTER W. ROSE
National Canners Association
1950 Sixth Street
Berkeley, CA 94710
LARS ROSENGREN
Swedish Embassy
Washington, DC 20037
JAMES D. ROUSSEL
Amstar Corporation
7417 North Peters Street
Arabi, LA 70032
EUGENE E. ROZACKY
Environmental Protection Agency
Permits Section
1600 Patterson Street
Dallas, TX 75201
PAUL H. RUSSELL, JR.
Harnish & Lookup Associates
615 Mason Street
Newark, NY 14513
JAMES A. SANTROCH
Environmental Protection Agency
100 California Street
San Francisco, CA 94111
THOMAS N. SARGENT
Environmental Protection Agency
Southeast Water Laboratory
College Station Road
Athens, GA 30601
KENNETH H. SAULS
Amstar Corporation
1253 Avenue of Americas
New York, NY 10020
LOUIS SAVARESE
Beech-Nut, Inc.
Canajoharie, NY 13317
W. J. SAVOY
Cities Service Oil Co.
2100 Orchid
Lake Charles, LA 70601
JOHN E. SCHENK
Environmental Control Technology
3983 Research Park Drive
Ann Arbor, MI 48104
CURTIS J. SCHMIDT
SCS Engineers
4014 Long Beach Boulevard
Long Beach, CA 90807
RONALD C. SCHMIDT
Ionics, Inc.
P. 0. Box 99
Bridgeville, PA 15017
CHARLES E. SCHOLLMEIER
A. E. Staley Mfg. Co.
Route 7, Majors Lane
Decatur, IL 62521
G. H. SCHWARTZ, Jr.
Sverdrup & Parcel
800 North 12th Street
St. Louis, MO 63101
496
-------
J. M. SHACKELFORD
Environmental Protection Agency
Washington, DC 20460
A. L. SHEWFELT
Georgia Experimental Station
Experiment, GA 30212
KIM SHIKAZE
Dept. of Environment
Ottawa, Canada KIV-8N2
HOWARD H. SHOCKEY
National Fruit Products Company
P. 0. Box 609
Winchester, VA 22601
CHARLES D. SIEBENTHAL
Metcalf & Eddy
1029 Corporation Way
Palo Alto, CA 94303
ADEN R. SIRLES
Komine, Sanderson Engineering Corp.
11 West Oxmoor Road
Birmingham, AL 35209
CHARLES SMALLWOOD, JR.
North Carolina State University
Mann Hall
Raleigh, NC 27607
GERALD T. SMITH
Environmental Protection Agency
2390 Palmour Drive, NE #11
Atlanta, GA 30305
A. L. STAFFORD
Virginia Dept. of Agriculture
1444 East Main Street
Richmond, VA 23219
LEONARD J. STAR
Fredonia Products Co.
Fredonia, NY 14063
MATTHEW M. STAWIARSKI
Central Soya Co., Inc.
1825 North Laramie
Chicago, IL 60639
RICHARD W. STERNBERG
National Canners Association
1133 - 20th Street, NW
Washington, DC 20036
HERBERT E. STONE
Del Monte Corporation
215 Fremont Street
San Francisco, CA 94022
LEALE STREEBIN
University of Oklahoma
School of Civil Engineering
202 H. Boyd
Norman, OK 73069
E. J. STRUZESKI
Environmental Protection Agency
Denver Federal Center
Denver, CO 80225
ROBERT W. SUCKER
Anheuser Busch, Inc.
610 Pestalizzi
St. Louis, MO 63118
A. J. SZABO
Domingue, Szabo & Assoc.
P. 0. Box 52115
Lafayette, LA 70501
RUSSELL H. THACKERY
Calgpn Corporation
Box 1346 Calgon Center
Pittsburgh, PA 15230
DONALD J. THIMSEN
General Mills, Inc.
9000 Plymouth Avenue, N.
Minneapolis, MN 55427
RONALD A. TSUGITA
Montgomery Consulting Engineers
3717 Mt. Diablo Blvd.
Lafayette, CA 94549
AMULYA D. TYAGI
Pavia-Byrne Engineering Corp.
431 Gravier Street
New Orleans, LA 70130
497
-------
DAVID R. VAUGHN
Dorr-Oliver, Inc.
77 Havemeyer Lane
Stamford, CT 06904
JOHN VILLAMERE
Environment Canada
1090 West Fender Street
Vancouver, 5, B.C., Canada
WILBERT L. WALKER
Ocean Protein, Inc.
1001 Pinhook
Lafayette, LA 70501
W. 0. WECKEL
Spreckels Sugar Division
of Amstar Corporation
2 Pine Street
San Francisco, CA 94106
CLARK L. WEDDLE
Bechtel, Inc.
350 Mission Street
San Francisco, CA 94105
PETER R. WENCK
Gerber Products Company
P. 0. Box 456
Newaygo, MI 49337
LLOYD E. WESTON
Webster, Foster & Weston
316 Cambridge Street
Grand Fork, ND 58201
RICHARD A. WIDSETH
Webster Foster & Weston
216 South Main Street
Crookston, MN 56716
FREDERICK WILLIAMS
Ontario Research Foundation
Sheridan Park
Mississauga, Ontario, Canada
JACK L. WITHEROW
Environmental Protection Agency
P. 0. Box 1198
Ada1, OK 74820
BOBBY J. WOOD
National Marine Fisheries Service
P. 0. Drawer 1207
Pascagoula, MS 39567
S. C. YIN
Environmental Protection Agency
Robert S. Kerr Water Res. Ctr.
P. 0. Box 1198
Ada, OK 74820
6U.S. GOVERNMENT PRINTING OFFICE: 1972-514-149/90
498
-------
SELECTED WATER
RESOURCES ABSTRACTS
INPUT TRANSACTION FORM
J. Report No.
2.
Proceedings Third National Symposium on
Food Processing Wastes
7. *««*«%c1f1c Northwest Water Laboratory, EPA
and National Canners Association
9. Orgamzatlon Nati0nal Waste Treatment Research Program
Pacific Northwest Water Laboratory, EPA
Corvallis, Oregon
12. Sponsoring Organization
IS. Supplementary Notes
£RA an{|
Environmental Protection Agency report
number EPA-R2-72-018, November 1972 .
3. Accession No.
w
5. Report Date
6.
8. Performing Organization
Report No.
10. Project No.
12060—08/72
11. Contract/Grant No.
13. Type of Report and
Period Covered
March 28-30, 1972
ic. Abstract There were 23 papers presented on process modification, by-product
recovery, process water reduction, and wastewater treatment for many different
types of food processing.
Approximately 300 members of industry, consulting firms, universities,
and state and federal agencies participated in the 3-day meeting in New Orleans, La.,
where such items as dry caustic peeling, vegetable blanching, reverse osmosis,
ultrafiltration, biological treatment, tertiary treatment, wastewater characterization,
ocean assimilation, and federal research and effluent guidelines were discussed.
17a. Descriptors
*Waste Water Treatment, *Water Pollution Control, industrial Wastes,
Canneries
/ 7b. Identifiers
Industrial Waste Treatment, Food Waste Treatment, Process Water Reduction,
By-Product Recovery, Wastewater Characterization, Combined Treatment of
Domestic and Industrial Wastes
17c. COWRR Field & Group
18. Availability
19. Security Class.
(Report)
20. Security Class.
(Page)
21. No. of
Pages
A bstractor
Send To:
WATER RESOURCES SCIENTIFIC INFORMATION CENTER
US. DEPARTMENT OF THE INTERIOR
WASHINGTON. D. C. 20210
WRSIC 102 (REV JUNE 1971)
------- |