WATER POLLUTION CONTROL RESEARCH SERIES • 12130 FJQ 06/71
Pollution Abatement
and By-Product Recovery
in Shellfish and Fisheries Processing
U.S. ENVIRONMENTAL PROTECTION AGENCY
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WATER POLLUTION CONTROL RESEARCE SERIES
The Water Pollution Control Research Series describes the
results and progress in the control and abatement of pollu-
tion of our Nation's waters. They provide a central source
of information on the research, development, and demon-
stration activities of the Environmental Protection Agency
through inhouse research and grants and contracts with
Federal, State, and local agencies, research institutions,
and industrial organizations.
Inquiries pertaining to the Water Pollution Control Research
Reports should be directed to the Head, Publications Branch,
Research Information Division, R&M, Environmental Protection
Agency, Washington, D.C. 20460.
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POLLUTION ABATEMENT AND BY-PRODUCT RECOVERY
IN SHELLFISH AND FISHERIES PROCESSING
by
CRESA, a joint venture of
Food, Chemical and Research Laboratories, Inc.
4900 Ninth Avenue Northwest
Seattle, Washington 98107
and
Engineering-Science of Alaska
326 "I "Street, Suite 31
Anchorage, Alaska 99501
for the
ENVIRONMENTAL PROTECTION AGENCY
Project # 1SL30P JO
(Formerly 11060FJQ)
June 1971
For sale by the Superintendent of Documents, U.S. Government Printing Office, Washington, D.C. 20402 - Price $1
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EPA Review Notice
This report has been reviewed by the Environmental
Protection Agency and approved for publication. Approval
does not signify that the contents necessarily reflect
the views and policies of the Environmental Protection
Agency, nor does mention of trade names or commercial
products constitute endorsement or recommendations for
use.
11
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ABSTRACT
Laboratory and pilot plant studies show that utilizable by-products
can be obtained from shell fish wastes produced at Kodiak, Alaska.
Alkali extraction of the contained protein leaves a matrix of chitin
and calcium carbonate (CaCO ). The chitin-CaCO matrix can be
converted chemically into its components.
Other fishery wastes found at Kodiak; salmon waste and small fish
associated with shrimp can be liquified by alkali treatment, partially
neutralized with acid, and converted into oil, bone meal and 50%
solubles.
The economics and pollution abatement capabilities of a proposed
plant are discussed. The construction and operation of this plant
would reduce the yearly pollution load from the present 22. 1 million
Ibs per year of C. O. D. being dumped into Kodiak Harbor to 6. 6
million Ibs per year of C. O. D.
Preliminary designs are submitted for the implementation of this
process, together with indicated markets and plan of operation.
This report was submitted in fulfillment of Project Number 11060 FJQ,
under the (partial) sponsorship of the Water Quality Office, Environ-
mental Protection Agency.
m
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CONTENTS
Section
III
IV
V
VI
VII
VIII
IX
X
XL
XII
XIII
XIV
XV
XVI
XVII
Conclusions
Recommendations
Introduction
The Present Pollution Problem
Process Description
Pollution Abatement
Laboratory Investigations
Markets
Proposed Facilities
Economic Considerations
Pro Forma Business Structure
Alternate Disposal Methods
In-House Improvements at Processing Plants
Acknowledgments
References
Publications
Appendix
Page
1
3
5
9
19
23
27
51
55
65
71
73
75
77
79
81
83
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FIGURES
No. Page
1 Map: State of Alaska 6
2 Processing Plant Locations at Kodiak Harbor 10
3 Shrimp Production at Kodiak, Alaska 13
4 Composition of Wastes by Percent 28
5 Extraction Rates for Shellfish Wastes 36
6 Oxygen Consumption by Shellfish Waste 40
7 Map: Location and Topography - Near Island 56
8 Dock and Trestle for the Proposed By-Product
Recovery Plant 58
9 Plan: By-Product Recovery Plant Process
Building 59
10 Schematic Flow Diagram - Scrap Fish from
Shrimp Processors, Crab Butchering Waste
and Salmon Fisheries Waste, Processing Unit 61
11 Schematic Flow Diagram - Shrimp Waste
Processing Unit 62
12 Schematic Flow Diagram - Crab Picking Line
Waste Processing Unit 64
VI
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TABLES
No. Page
1 Crab Production in 1970 for the KodiakArea 14
2 1970 Salmon Production at Kodiak 17
3 Pollution Load 23
4 Water Usage by Processors at Kodiak 24
5 Amino Acid Composition of Spray Dried
Shellfish Waste Proteins ' 33
6 C.O.D. Values of Shellfish Waste 39
7 Waste Distribution in Shrimp Processing
A. Raw Peeling 42
8 Waste Distribution in Shrimp Processing
B. Peeling after Steaming 43
9 Cooking Whole Crab 45
10 Live Butchered Crab 46
11 Sales/Year - Income from Disposal Fee 67
12 Yearly Operating Expenses 68
13 Plant Investment - June 1971 Prices 69
VII
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SECTION I
CONCLUSIONS
1. The present pollution load discharged to Kodiak Harbor as wastes
from shellfish and fish processing is about 22.1 million Ibs of C. O. D.
per year. This is roughly equivalent to the domestic wastes from a
city of 250, 000 population.
2. A plan for collection and treatment of solid wastes to produce
marketable by-products has been developed.
Wastes would be collected in barges and transported to a site on Near
Island for by-product recovery. Shellfish wastes would be extracted
with dilute alkali to yield a high quality protein and a chitin-CaCO
residue as products. The protein would be marketable as a pet food
additive or for industrial applications. The chitin-CaCO_, residue
could be exported for conversion to chitin and derived products or
could be used in Alaska as a soil liming and fertilizer material.
Fish wastes would also be alkali extracted to yield a concentrated
protein product similar to fish solubles, oil and bone meal.
3. The proposed plan would accomplish a 70% reduction in the
present pollution load and is shown to be practical and economically
sound.
4. Any rational plan for complete pollution abatement by secondary
treatment of liquid wastes would require prior separation and disposal
of solid wastes.
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SECTION II
RECOMMENDATIONS
1. A pollution control district comprising all of the seafood process-
ing plants should be established.
2. A board of directors should be elected and managements should
be appointed.
3. A decision to construct a by-product recovery plant for solid
wastes, using processes developed in this study, should be made.
4. A plan for financing the enterprise should be developed.
5. Consultants should be retained for design, construction and
operation of the facility and for marketing of its products.
6. A schedule for construction of the facility should be prepared to
comply with Federal and State of Alaska regulations.
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SECTION in
INTRODUCTION
The City of Kodiak, Alaska, located on the northeast shore of Kodiak
Island (Figure 1), has been an important center for fish and shellfish
processing for many years. Starting in 1963, with development of the
Alaska King crab fishery, very rapid expansion of operations in Kodiak
occurred. Also a serious pollution problem developed.
Processing plants, now numbering 15, are spread over 2 miles of
waterfront and are generally located on docks or moored vessels.
Usual practice is to discharge all wastes into harbor waters adjacent
to the plant. In 1967 about 50 million Ibs of King crab waste were
so handled. Since then the King crab fishery has declined to 20% of
its peak but shrimp processing has increased to the extent that over
70 million Ibs of waste were discharged into Kodiak Harbor in 1970.
Food, Chemical and Research Laboratories, Inc. became acquainted
with the Kodiak pollution problem in 1966 as a result of discussions
with principals in the major processing companies for which the
Laboratories performed quality control services on products shipped
via Seattle. Several of these companies had, in the past, considered
recovery of solid wastes from shellfish processing by production of
a dried crude shellfish meal.
Economic analysis of costs and markets for such products led to the
conclusion that production costs in Kodiak and freight to Puget Sound
ports or other possible markets would be prohibitive.
As an alternate, Food, Chemical and Research Laboratories, Inc.
independently explored the possibilities of upgrading shellfish waste
by separating it into its principal components; protein, chitin and
calcium salts. It was found that a protein of high nutritional value
could be extracted from the shell by mild alkali treatment and that
chitin, after conversion to chitosan, was useful as a coagulant and
coagulant-aid in water and waste treatment. Possible return from
the waste was thus increased from about $20 per ton for dry crab
meal F. O. B. Kodiak to perhaps $200 per ton (500 Ibs protein at
$0. 15, 500 Ibs chitin at $0. 25).
One of the King crab producers, Pan Alaska Fisheries, supported
additional work on the proposed process and further studies were
supported by contracts from the U. S. Bureau of Commercial Fisheries,
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PT. BARROW
3
FIGURE 1
MAP
STATE OF ALASKA
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now National Marine Fisheries Service. These studies concluded that
extraction of protein from shellfish waste was economically practical
at Kodiak but that further processing of the residue, chitin and CaCO_
to obtain chitin should be done in areas where low cost hydrochloric
acid (HC1) was available. Alaska markets for the residue as a soil
liming agent and fertilizer appeared practical as an alternate disposal.
In 1969 the severity of the pollution problem at Kodiak and the imminent
need to comply with Federal and State of Alaska laws regarding waste
discharges prompted application to the Water Quality Office, Environ-
mental Frotection Agency for a research, development and demonstra-
tion grant to the City of Kodiak. Objectives stated in the application
were:
a. To design and construct a facility to effect abatement of primary
pollution from shellfish waste in Kodiak Harbor.
b. To demonstrate a shellfish by-product recovery process for
conversion of waste. The process may also be applicable in other
processing localities.
c. To develop in-house measures at shellfish processing plants for
reduction of secondary pollution levels.
The plan of work for the project initially was divided into seven tasks
as follows:
Task 1 - An engineering survey at Kodiak to:
a. Determine character, extent and distribution of pollution loads.
b. Obtain all basic data needed for preliminary design of waste
collection and recovery facility including optimum site location,
collection equipment and procedures, site improvements, probable
costs for fuel, labor, freight, power, water, etc.
c. Review operating practices and facilities at individual processing
plants to determine possibilities for in-house improvements and
changes needed to permit handling of wastes by the recovery facility.
Task 2 - Pilot plant and chemical studies at Seattle to obtain design
parameters for the recovery facility and to characterize wastes and
possible products.
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Task 3 - A market development study to determine acceptability of
products for possible end uses, potential sales volumes and prices.
Task 4 - Preparation of a Pre-construction Summary Report.
Task 5 - Engineering Design of Facilities.
Task 6 - Construction of Facilities.
Task 7 - Operation of system, for 1 year with demonstration of pollution
abatement, economic feasibility and training of personnel for continua-
tion of operation.
On April 6, 1970, Tasks 1, 2 and 4 of the application were funded
through a grant to the City of Kodiak with CRESA, a joint venture
between Food, Chemical and Research Laboratories, Inc. and
Engineering-Science of Alaska, as contractor. Task 3 was disallowed
as not within the allowable scope of EPA support. Tasks 5, 6 and 7
were deferred pending completion of Task 4 and approval.
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SECTION IV
THE PRESENT POLLUTION PROBLEM
Plant Locations
Figure 2 is a map of Kodiak Harbor showing locations of processing
plants. Starting at the southwest end of the harbor, these are:
1. American Freezerships (at Gibson Cove)
2. Alaska Ice and Cold Storage Inc.
3. East Point Seafoods Co.
4. King Crab Inc.
5. B and B Fisheries
6. Kinnear and Wendt Inc.
7. Ursin Seafoods, Inc.
8. Pan Alaska Fisheries, Inc.
9. Roxanne Fisheries, Inc.
10. Northern Processors, Inc.
11. Point Chehalis Packers, Inc.
12. Martins King Crab
13. Alaska Packers Association
14. Columbia-Ward Fisheries
15. Whitney-Fidalgo Seafoods, Inc.
The plant at Gibson Cove is on a converted ferry. The ferry is
moored below a rocky hill that makes land access difficult. The
site is about 1 mile southwest of the next plant in the line. Plants
2 through 10 are along a 1/2 mile stretch of waterfront southwest
of the breakwater for the small boat harbor. There are three plants,
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A K
American Freezer Ships (at Gibson Cove)
Alaska Ice and Cold Storage
East Point Seafoods
King Crab, Inc.
B and B Fisheries
Kinnear and Wendt
Ursin Sea Foods
10. Northern Processors
11. Point Chehalis Packers, Inc.
12. Martins Fresh King Crab
13. Alaska Packers
Pan Alaska Fisheries, Inc. 14. Columbia-Ward Fisheries
Princess Roxanne, Inc. 15. Whitney-Fidalgo Sea Foods
() J} J \
FIGURE 2
PROCESSING PLANT
LOCATIONS
at
BY-PRODUCT RECOVERY
—( ~ PLANT
KODIAK HRBOR
Stall- 1:1().0(H)
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11 through 13, just northeast of the boat harbor and the last two are
about a 1 /2 mile farther to the northeast.
Operations in the processing plants differ widely as to species handled,
size and type of pack. Some operations are more seasonal than others
so that the pollution load varies widely throughout the year as to
character, volume and distribution.
Shrimp Processing
Alaska shrimp are smaller than shrimp caught in most other areas
with counts of 350 to 450 per Ib on a peeled weight basis. Processing
consists of sorting out small scrap fish and debris (caught in the trawls
with the shrimp) and mechanical peeling with or without a quick steam
precook. The precook requirement depends on the type of peeler used.
After peeling and washing the shrimp are packed for freezing or
canning.
Since 1969 shrimp processing has been by far the major operation at
Kodiak and its relative importance is still increasing in 1971. There
are now six shrimp processors, all in the group southwest of the boat
harbor with major producers at the southwest end of the line. While
both canning and freezing operations are conducted, from a pollution
standpoint there is little difference in the character or amount of
waste generated as a fraction of the live weight. All plants use
mechanical peelers which typically recover about 18% of the live
weight as salable product leaving 82% as waste. Water usage averages
about 7. 5 gals, per Ib of live weight processed but varies from 5 to 10
gals, depending on peeler design and operation and the production rate.
To evaluate the pollution load from shrimp processing, laboratory
studies were conducted (see SECTION VII) on the distribution of
suspended and dissolved solids and Chemical Oxygen Demand (C. O. D.)
of waste fractions generated in different processing operations. This
was done simulating procedures with both old and new style peelers.
The former peel raw shrimp after a preliminary aging period and the
latter use a rapid steam cook without aging before peeling. It was
found that with old style peelers only 60% of the total waste solids
and 57. 2% of the total waste C.O. D. is recoverable in the shell portion
with most of the remainder as solubles in the peeler water. With new
style peelers 70% of the waste solids and C. O. D. is recoverable in
the shell portion. Apparently the precook reduces soluble losses.
11
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The total C. O. D. in shrimp waste was found to be 0. 21 Ibs per Ib of
live weight for both types of peelers. Five day Biochemical Oxygen
Demand (B. O. D. ) for the solid portion of shrimp waste approached
an ultimate value under laboratory conditions and amounted to 48%
of the C. O. D. How rapidly the waste may be consumed under Kodiak
Harbor conditions has not been established.
Figure 3 presents 1970 production data for shrimp at Kodiak. The
four plants operating in 1970 show roughly the same seasonal variation
in pack with a minimum in May, the molting season, and a maximum
in July. The monthly average for 1970 was 5.21 million Ibs live weight.
For June, July, August and September the monthly average was 7. 20
million Ibs live weight. The total for 1970 was 62. 6 million Ibs live
weight. In 1971 two new processors, one with production about equal
to the largest operator for 1970, and another smaller operator entered
the field, and a 50% increase in production was planned by one other
plant. The projected increase for 1971 is 75% of 1970 production.
From above data the 1971 pollution load from shrimp processing at
Kodiak can be calculated at 16. 6 million Ibs of C.O.D. or 8 million
Ibs of B. O. D. per year. Removal of solid wastes would reduce this
load by 70%. The remaining 30% solubles are contained in 750 million
gals, of process water per year.
Crab Processing
Since the peak of King crab production in 1967, which amounted to
about 50 million Ibs live weight at Kodiak, this fishery declined to
about 9.7 million Ibs in 1970. There has been an increase, however,
in the production of smaller species, Tanner and Dungeness crab,
with a total for all species of 20.47 million Ibs in 1970 (Table 1).
King crab fishing is now restricted to the period from August through
January. Dungeness crab are not fished during the period January
through April and Tanner crab production is at a very low level from
June through December. In 1970 total crab production showed a high
of 3. 58 million Ibs per month in September with a low in May of 0. 74
million Ibs and June of 0. 73 million Ibs.
In 1970 there were nine plants processing crab at Kodiak and these
were scattered along the full length of the waterfront. Crab process-
ing differs from shrimp in that the amount of waste generated depends
on the type of product. Some of the crab is picked from the shell and
marketed as canned or frozen crab meat. Some crab is marketed
as whole leg sections in shell and some as frozen whole crab. Data
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H
O
LU
I
2
to
O
SHRIMP PRODUCTION
at
KODIAK, ALASKA
TOTAL FOR
FOUR PLANTS
Jan Feb Mer Apr May Jun Jul Aug Sep Oct Ncv Dec
YEAR of RECORD
FIGURE 3
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TABLE 1
CRAB PRODUCTION IN 1970 FOR THE KODIAK AREA
Millions of Lbs - Live Weight
(Source - Alaska Department of Fish and Game)
Kodiak Area Citv of Kodiak (80%)
Month
Jan.
Feb.
Mar.
April
May
June
July
Aug.
Sept.
Oct.
Nov.
Dec.
Total
King
1.29
-
-
-
-
-
-
1.69
3.69
2.47
1.73
1.22
11.81
Tanner
0.71
1.21
2.73
1.74
0.76
0.18
0.14
-
0.01
0.01
0.12
0.14
7.75
Dungeness
-
-
-
-
0.16
0.73
1.91
1.51
0.78
0.49
0.13
0.02
5.73
King
1.03
-
-
-
-
-
-
1.35
2.95
1.98
1.38
0.98
9.67
Tanner
0.57
0.97
2.19
1.39
0.61
0.14
0.11
-
0.01
0.01
0.10
o.n
6.20
Dungeness Total
-
-
-
-
0.13
0.59
1.53
1.21
0.62
0.39
0.10
0.02
4.58
1.60
0.97
2.19
1.39
0.74
0.73
1.64
2.56
3.58
2.38
1.58
1.11
20.47
14
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from individual plants indicate that in 1970 about 69% of the total crab
marketed was as frozen or canned meat, 25% as leg sections and 6%
as frozen whole crab. Solid wastes generated by the three different
products are 63%, 47% and 1% of live weight respectively.
To determine the total pollution load from crab processing and the
amounts of wastes generated in the principal operations of butchering,
cooking and picking a series of experiments similar to those on shrimp
processing was conducted (See SECTION .VII). Live Dungeness crab
from Westport, Washington were used for these studies. It is believed
that very nearly the same results would be obtained with other species.
To simulate different plant practices, some crab were cooked whole
before butchering and picking and others were butchered first, cooking
only deviscerated bodies and leg sections.
Very nearly the same results were obtained by the two procedures.
The total yield of meat was 31% in the first case and 33% in the second
compared with an average of about 25% in practice. The total C. O. D.
of wastes was 0.16 and 0.14 Ibs G. O.D. per Ib of live weight for the
two treatments. Soluble losses in cooking and picking water were in
both cases 12% of the total C. O. D. of the waste. Of this only about
6. 7% was cooking losses. This is notably much less than found for
shrimp. Backs and viscera account for about 49% to 50% of the total
waste C. O. D. and the remainder, 39% is in the shell from the picking
lines. Some studies in 1968 on cooking King and Tanner crab showed
a similar distribution of solids and presumably of C. O. D. (1).
The total pollution burden, due to crab processing in 1970, may be
calculated as follows:
Product C. O. D. (Ibs)
Whole crab (20. 4 x 106) (0. 06)(0. 15)(0. 067 ) - 12,400
Leg section (20. 4 x 1Q6) (0. 25)(0. 15)(0. 56) = 430,000
Picked meat (20.4 x 106) (0. 69)(0.15)(1.00) = 2.110. OOP
Total 2,550,000
Of this, over 85% could be eliminated by recovery of backs, viscera
and picking line shell.
Salmon Processing
In 1970 there was a very large pack of salmon at Kodiak. It amounted
15
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to about 200, 000 48 Ib cases of canned salmon and about 2. 6 million
Ibs of frozen salmon (Table 2). The live weight of fish processed per
case is about 83 Ibs leaving 35 Ibs of waste per case. Total waste
from canned salmon was thus about 7 million Ibs. Since salmon are
frozen eviscerated with heads, wastes generated from this source
would be about 750,000 Ibs in 1970. Total salmon waste was thus
about 7. 75 million Ibs.
As indicated in Table 2 the season extended from June 1 3 to September
13 with 90% of the production during July and August. There was a
pronounced peak from July 12 to August 9 with production averaging
5, 000 cases per day and 46, 500 Ibs per day of frozen salmon for this
4 week period. This would amount to about 185, 000 Ibs of salmon
waste per day.
Salmon are processed at points extending the full length of the water-
front. From the City of Kodiak records water usage is about 1. 75
gals, per Ib of salmon processed. During the peak season water used
for salmon processing would thus be about 830,000 gals, per day. The
C. O. D. of screened salmon waste can be estimated as follows:
Representative analysis: solids, 20%; protein, 40% of solids; fats,
30% of solids.
C.O.D. of protein (0. 20)(0. 40) 1. 35 = 0.1041b
C.O.D. of fat (0.20)(0.30) 2.95 = 0. 177 Ib
Total C. O. D. per Ib of drained weight= 0. 281 Ib
For the 1970 season this would be 2. 2 million Ibs of C. O. D. with
50, 000 Ibs per day during the peak period.
The volume of water associated with salmon packing and the extended
distribution of processing plants along the waterfront indicate that
complete elimination of the pollution load by collection and processing
of both liquid and solid wastes would be impractical at this time.
Studies conducted at a salmon cannery operation at La Conner, Wash-
ington during the 19?0 season indicate (2) that screening (40 mesh
screen) of wastes at the processing plants with collection of solids
would remove 80% to 85% of the C. O. D. load.
Scrap Fish and Other Fishery Wastes
The principal scrap fish source is small fish caught in the shrimp
trawls. These are sorted out prior to peeling and generally amount
16
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TABLE 2
1970 SALMON PRODUCTION AT KODIAK
Cases Packed
Frozen Salmon
Week Ending
6-13
6-21
6-28
7-5
7-12
7-19
7-26
8-2
8-9
8-16
8-25
8-30
9-6
9-13
Total
48 Ibs each
1, 781
1,232
17, 508
789
14, 774
37, 838
34,835
40, 006
26, 714
10.612
13, 131
5,314
514
-
205, 048
Ibs
-
95,280
74,664
27,270
77,402
257,356
392, 827
371,214
275,276
19,829
61, 164
562,417
-
399,709
2,614,408
17
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to 3% of the shrimp weight. For the year 1971 this would be 3 million
Ibs. Other sources, such as herring and halibut trimmings, are of
minor significance. Crab butchering waste would probably be collected
with scrap fish, but it has already been considered in the previous
discussion.
Assuming a C. O. D. load for scrap fish equal to that of salmon waste,
the total would be 800,000 Ibs of C. O. D. per year.
The Total Pollution Load
In summarizing data for individual sources, indications are that the
total pollution burden discharged into Kodiak Harbor as shellfish and
fishery wastes in 1971 will be as follows:
Lbs. C. O. D. /year
Shrimp waste 16, 600, 000
Crab waste 2,500,000
Salmon waste 2, 200, 000
Scrap fish 800.000
Total Pollution Load 22, 100, 000
These figures assume that total shrimp production for the year will
be 75% greater than in 1970, and that crab and salmon processing
would be about the same as in 1970. The increase in shrimp is based
on the number of new peelers and may not materialize in actual
production.
18
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SECTION V
PROCESS DESCRIPTION
The Collection System
The dispersion of processing plants, the diverse character of wastes,
the seasonal variation of waste generation and the volume of wastes to
be handled during peak periods all point to a barging system as the
most practical solution to the waste collection problem. Other possi-
bilities such as truck hauling, fluming or pneumatic pipe lines for
transport to a processing site have been considered but appear to
involve either much greater initial investment or much greater operat-
ing cost. It is believed that the load could be handled by a fleet of 12
small barges with 1 work boat for towing to the by-product recovery
site. Solid decked barges with bins would be used. Where possible,
barges would be spotted at processing plants to collect wastes as
generated. Insofar as possible wastes would be segregated into three
classes:
1. Shrimp peeler waste.
2. Crab picking line waste.
3. Fishery waste (includes crab butchering waste).
Barges could be compartmented where simultaneous collection of more
than one class of waste was needed. Scrap fish from shrimp trawls
and crab butchering waste would be collected on a total recovery basis.
Salmon wastes would require screening at the processing plants before
collection.
It appears likely that the entire barging operation could be contracted
to one of the towing companies. Existing small barges could probably
be used so that deck bins would be the only investment.
Site Location
Criteria for site location used in the study have been as follows:
1. Availability of land.
2. Adequate size to accommodate recovery plant, fuel and product
storage and dock facilities with possible expansion to include secondary
liquid waste treatment.
3. Location compatable with collection system to minimize transporta-
tion costs.
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4. Availability of utilities.
There appeared to be no site along the Kodiak waterfront which would
meet all of these criteria. The site which has been selected is at the
southern tip of Near Island directly opposite the breakwater at the small
boat harbor. This site is owned by the City of Kodiak and is presently
unimproved. The available area is ample for the by-product recovery
plant and any foreseeable expansion. The topography is reasonably flat
with an average elevation of 20 - 45 ft above low tide level. Site im-
provement costs should therefore be reasonable.
There is water on Near Island which by impounding should be adequate
for the by-product recovery plant. If supplementation becomes neces-
sary barge transport is feasible. A diesel generator installation is
planned for electric power. Waste heat from the generator would
supply a substantial part of heat needed for the protein extraction
process.
By-Product Recovery Process
Crab and shrimp shell would be unloaded from barges by pneumatic
pipe line. It would be coarsely ground with a hammer mill and passed
to continuous alkali extraction units in which the shell proteins would
be solubilized and extracted by dilute NaOH passing through the units
countercurrent to the shell. Final sections of the units would be used
to wash the extracted shell and the NaOH would be added at several
points to maintain sufficient alkalinity for complete protein extraction.
Average extraction temperature vtould be 140°F and residence times
would be about 2 hours for crab waste and 1 hour for shrimp waste.
Laboratory and pilot plant studies indicate that these conditions repre-
sent an optimum balance between efficient protein extraction and
minimum protein degradation. Other factors such as equipment
design, alkali concentration and liquor-to-solids ratio will be of
influence in actual plant operation.
The sodium proteinate extract liquor would be clarified and treated
with dilute HC1 to a pH of about 4. 0 precipitating the protein. The
slurry of precipitated protein would pass to a centrifuge for dewatering
and washing; the washed cake would be dried and bagged.
The extracted shell would be dewatered with a screw press and shipped
in bulk to either a Puget Sound port for conversion to chitin and
calcium chloride or to Alaska ports for use as a soil fertilizer and
liming agent. Burning to yield heat and lime is also possible.
20
-------
Centrifugate liquor from protein recovery containing 2% to 3% of the
C. O. D. of collected wastes would be discharged to harbor waters or
ultimately be subjected to secondary treatment.
Fishery wastes would also be pneumatically unloaded and wet ground
to a gurry. This would be processed with dilute NaOH in a concurrent
unit to dissolve the protein. The treated waste would be screened to
remove bone and centrifuged to remove oil. These products would be
further processed to meet market requirements. The clarified
protein liquor would be neutralized and evaporated to about 50% solids.
The product would be similar to the "fish solubles" now produced from
fish meal operations.
21
-------
SECTION VI
POLLUTION ABATEMENT
The collection system and waste processing plan described previously
would completely eliminate discharge of solid fish and shellfish wastes
into Kodiak Harbor. The effect on the pollution load would be as shown
in Table 3.
TABLE 3
POLLUTION LOAD
Lbs per Year
C. O. D. Removed Residual
Waste Total C. O. D. In Solids C. O. D.
Shrimp Waste 16,600,000 11,100,000 5,500,000
Crab Waste 2,500,000 2,000,000 500,000
Salmon Waste 2,200,000 1,870,000 330,000
Scrap Fish 800.000 800, OOP -0;
Totals 22,100,000 15,770,000 6,330,000
Without secondary treatment of effluents from the protein recovery
process, about 2% of the C.O. D. in solid shrimp and crab waste
would be discharged as nonprecipitated protein. This would amount
to 260, 000 Ibs of C.O. D. per year. Overall pollution abatement
would thus be 15, 770,000 - 260, OOP = 70% of the present pollution
22, 100,000
load. This is essentially all that could possibly be accomplished by
elimination of solid waste discharge.
If elimination of the residual 30% of the C. O. D. becomes obligatory,
by new Federal and State of Alaska laws, collection and secondary
treatment of liquid wastes would be required. Table 4 shows the
volume of the water used by processors which would be roughly
equivalent to liquid wastes. This would involve an industrial sewer
the full length of Kodiak waterfront. Possibly a separate system
could be constructed at Gibson Cove.
Also the sewer and treatment plant could be combined with a sanitary
sewer system for the City of Kodiak. These possibilities are beyond
the scope of the present study. It can be said, however, that the
Z3
-------
TABLE 4
WATER USAGE BY PROCESSORS AT KODIAK
Millions of Gals./Mo
1969 1970 Total
Mar Apr May June July Aug Sept Oct Nov Dec Jan Feb Mar Apr May 15 Mo
East
Point 13.4 10.6 9.0 18.1 18.1 20.7 17.8 12.8 19.0 11.4 19.4 23.2 24.4 28.1 14.1 256.2
Shrimp Canning Only
King
Crab
Inc 3.1 11.2 11.8 11.7 12.0 3.1 1.8 6.9 3.8 0 0 0 0 0 0 70.4
Crab Salmon Canning Herring
B&B Fish-
eries 10.2 10.5 10.1 3.3 6.0 8.8 9.3 8.9 5.9 4.9 9.3 6.2 7.9 9.8 3.0 114.1
All species Herring
Reefer
King 0.5 9.2 10.5 5.3 0 1.5 2.9 1.9 1.6 2.4 10.3 10.8 11.4 11.9 2.7 82.9
Mostly Shrimp
Ursln Sea
Foods 2.3 1.2 0.2 0.2 0.3 1.9 1.8 2.0 0.5 2.5 2.4 0.8 2.1 1.0 0 19.2
Crab
Princess
Rox-
anna 2.8 4.2 3.3 2.1 3.9 3.0 3.8 3.2 0.5 3.5 5.6 5.8 11.8 3.3 1.1 57.9
Crab
Klnnear &
Wendt 8.0 5.6 3.6 7.5 11.0 10.2 7.8 4.0 7.0 4.6 10.0 8.4 9.3 10.3 4.0 111.3
Shrimp freezing and canning
Northern
Processors 0 0 0 0.6 2.1 2.8 2.7 1.4 0.2 0.6 0.6 0 0 0 0.2 11.2
All species except Shrimp
Martins
King
Crab 1.5 1.6 1.2 0.7 0.7 1.0 1.1 1.1 0.2 1.7 1.8 0.7 1.9 2.4 0.4 18.0
Crab
Pt. Che-
halls 0.7 1.1 1.8 0.6 3.3 3.8 3.1 1.5 0.6 1.0 1.2 1.2 1.7 1.6 0.3 23.5
Oungeness Crab Mostly
Alaska
Packers 000000 5.7 6.4 1.2 000 0.1 0 0 13.4
Salmon
Columbia
Ward 0.1 0 0.1 0.6 1.7 3.2 1.1 2.1 0.5 0.5 1.1 0.1 0.2 0.1 0.2 11.6
Canned King Crab Only
Whitney
Fldalgo 2.3 4.2 2.6 0.1 1.5 4.3 3.2 1.7 0.1 O _0 _0 1.0 6.4 4.9 32.3
Crab and Salmon
Total 44.9 53.2 53.6 47.0 60.3 73.2 63.4 48.8 44.2 36.9 61.7 57.2 71.8 74.9 30.9 822.0
24
-------
problem would be insolvable, or at least exceedingly difficult, without
prior elimination of solid wastes.
25
-------
SECTION VII
LABORATORY INVESTIGATIONS
Information presented in this section covers typical experimentation
which has been conducted in the laboratories at Seattle, Washington.
Much of the data is taken from progress reports submitted during the
course of the study. Some data from prior reports is included to
illustrate investigative procedures.
Laboratory investigations included protein recovery from King crab
butchering waste and King crab picking line waste. Losses in wash
water from the screening of crab wastes were measured. Similar
investigations were conducted on Dungeness crab picking line waste.
The recoverability of protein from NaOH-protein rich solution by
isoelectric precipitation with HC1 was investigated.
Factors influencing protein quality and rate of protein extraction from
crab and shrimp waste have been investigated. C. O. D., B. O. D.
and soluble waste losses have been determined for shellfish waste.
Salmon offal was investigated for protein extraction and solids losses
on screening.
Figure 4, a ternary diagram showing approximate shellfish waste
compositions, is a useful representation for calculation of changes
in extraction operations and comparison of product yields. The point
shown for Red crab represents the whole animal. It is not pertinent
to the Kodiak situation but illustrates possible application of the protein
extraction process in other localities. Red crab is a small pelagic
crustaceous species occurring in large swarms in temperate and sub-
tropical ocean waters. Harvesting for human food has been proposed (3).
King Crab Butchering Wastes
About 200 Ibs of King crab butchering waste were collected by one of
the processing plants in Kodiak, frozen and sent to Seattle. Analyses
and processing experiments on this material have been conducted.
The material as received (frozen in 30 gal. plastic pails) was very
inhomogeneous, consisting of carapaces, gills, blood and viscera,
all in unground condition. To obtain an approximate analysis, about
27
-------
Chitin
FIGURE 4
COMPOSITION OF WASTES
BY PERCENT
to
00
CaCOg
& Other
V\. A
DUNGENESS
Protein
-------
1/2 Ib of material was selected, using ratios previously determined
from butchering whole crab, to represent the entire waste. This was
ground with a measured volume of water in a Waring blender and
analyzed with results as follows:
Solids: (corrected for added water)
26. 6 26. 1 Average 26. 3%
Ash: (dry basis)
32.4 32.0 Average 32. 2%
Nitrogen: (dry basis)
8.00 7.96 8.06 Average 8.0%
Fat: (dry basis)
8.17 8.36 Average 8.3%
The probable composition of the waste on a dry basis can be calculated
from above data to be:
Ash 32% Fat 8%
Protein 48% Chitin 11%
This assumes 6. 9% nitrogen in chitin and 15. 0% nitrogen in protein.
Previous studies (4) on crab picking line wastes (all species) have
indicated that these materials can be wet-ground to 1/8 to 1 /4 mesh
and collected on a 40 mesh screen with very little loss (less than 1%)
of suspended solid materials.
Two Ibs of King crab butchering waste were wet-ground in a Hobart
garbage grinder and collected on a 40 mesh screen. Material passing
through the screen and solids collected on the screen were separately
analyzed with results as follows:
Total Solids:
Retained on 40 mesh 136.0 grams
Through 40 mesh 100. 5 grams
Percent through 42. 6 %
Fat:
Retained on 40 mesh 1. 7 grams
Through 40 mesh 8. 8 grams
Percent through 83. 7 %
29
-------
Protein:
Retained on 40 mesh
Through 40 mesh
Percent through
60. 0 grams
62. 7 grams
51. 1 %
B. O. D. of Effluent (estimated from analysis) = 13, 000 ppm
It is apparent from the analyses that crab butchering wastes could
not be handled in the above manner if a high degree of pollution abate-
ment is to be achieved. Accordingly, an experiment was conducted
on the whole waste to determine its behaviour in the alkaline extraction
process.
Selected frozen waste, 250 grams [protein = 250(0. 263)(0.48) = 31 grams]
was mixed with 400 grams of water and ground a few seconds in a
Waring blender. A solution of 10% NaOH (79 grams) was then added
and the slurry was stirred mechanically at 60° C for 1 hour. The solid
matter was then collected on a Buchner funnel. Water and NaOH were
again added to the solid residue and it was reextracted at 60° C for
1 hour as before. Solids were again collected and washed. Extract
fractions from the treatment were analyzed with results as follows:
1 st extract (565 ml)
Total nitrogen
Fat
2nd extract (485 ml)
Total nitrogen
Fat
5.49 mg/ml
3.75 mg/ml
0.75 mg/ml
0.02 mg/ml
The solid residue was not analyzed. Protein extracted in the first
treatment amounted to:
5.49/1000x565/0.15 = 20. 7 grams
and in the second:
0.75 /1000 x 485/0. 15 =
2. 44 grams
About 90% of the total extracted protein was obtained in the first
treatment. The second treatment probably could have been omitted
and the residual protein removed by simple washing. Total protein
recovery was only 75% of that calculated from the waste analysis.
This probably represents nonprotein nitrogen in viscera. Similar
30
-------
results have been obtained on salmon waste.
Fat removed in the first treatment was 2. 12 grams and in the second
0.0097 grams. The first treatment was practically quantitative.
The amount of alkali consumed in the extraction treatment was
determined by potentiometric titration of a sample of the first extract.
Fourteen ml of 1.0389N HC1 were required to the isoelectric point
(pH = 4.0) for a 50 ml sample. From this a NaOH consumption of
1 3. 6 Ibs per 100 Ibs of protein in the waste may be calculated.
Protein recovery by isoelectric precipitation from butchering waste
extracts shows lower recovery than from picking line waste extracts.
Fat appears to be thoroughly emulsified in the alkaline extract, but
may be separable by centrifugation at some intermediate pH between
that of the extract (about 13.0} and that at which protein precipitation
begins (about 5. 5).
Dungeness Crab Protein
During August, 1970, an extended study of the alkali extraction process
as applied to Dungeness crab picking line waste was conducted. Nine
extraction runs were conducted using three mixer charges with 45 Ibs
of crab waste per mixer in each run. Each batch was subjected to
two extraction treatments using 6. 75 Ibs of 10% NaOH solution, 0. 75
Ibs of sodium bisulfite and 50 Ibs added water per extraction! The
first extraction was at 60° C for 1. 5 hours. Following this the extract
was drained from the shell, a new charge of 6. 75 Ibs 10% NaOH and
50 Ibs water was added and extraction conducted for 1 hour at 60° C.
The second extract was drained to the sewer in these studies since
trial experiments showed that its protein content did not warrant
recovery in pilot plant operation.
Following the second extraction the shell was washed with water four
times in the mixers, drained and refrozen for possible chitin isolation
at a later date. The first extract liquor was neutralized to pH 4. 0 with
dilute HC1 to precipitate protein. This was allowed to settle overnight
under refrigeration. The supernate, amounting to about 3/4 of the
total volume, was decanted and the precipitate was twice washed with
water by reslurrying, settling and decantation. The washed precipitate
was collected on a Buchner funnel and frozen in bricks 8x10x2 inches
for storage. About 150 Ibs of frozen cake were obtained from the nine
runs with an average solids content of about 20%. Ash on a representa-
tive sample amounted to 1. 02%. This material was used for spray
31
-------
drier performance studies, feeding experiments, and evaluation in
pet food formulations.
Recoverability of Protein by Isoeiectric Precipitation
Results from earlier experiments in July, 1969, and prior indicated
that the solubility of alkali extracted protein at its isoelectric point
would be about 5 grams per liter (0. 5%). To attain 95% protein re-
covery would thus require a protein concentration in the extract of
10%. This placed emphasis on the need for countercurrent treatment
in order to build up the protein concentration in the extract to the
desired level.
Subsequent studies have shown that protein solubility at the isoelectric
point (actually, the pH of minimum solubility) is to some degree
affected by the severity of the alkali treatment and to a very large
degree is a linear function of the salt concentration. Since there is
a minimum alkali combining capacity of about 10% for the extracted
protein equivalent to about 14. 6% of the protein as salt on neutraliza-
tion, it is not possible to increase the protein concentration without
increasing the salt concentration proportionally. One could, of
course, consider desalting procedures such as dialysis, reverse
osmosis or ion exchange, but these would not be economic in the
process. In addition, the added time of treatment to achieve high
protein concentrations in the effluent would result in more degradation
and more isoelectric protein solubility.
Preceding conclusions point to an extraction process in which alkali
concentration, total alkali used and time of contact are all minimized.
In recent experiments these objectives have been approached and
results have been encouraging. In one experiment an isoelectric
protein solubility of 0. 25% was attained at a salt concentration of
1. 3%. This would amount to a protein recovery of 97. 2% from an
8,9% protein solution, assuming minimum alkali consumption.
The use of sodium hexametaphosphate to complex and precipitate
additional protein from the supernate as suggested by Mr. John
Spinelli (5) of the Seattle National Marine Fisheries Service also
shows considerable promise. In one experiment protein solubility
was reduced to 0. 07% representing a recovery of 96. 5% from a 2. 37%
protein solution.
Factors Influencing Protein Quality
In Table 5 data are presented on amino acid composition of spray dried
32
-------
TABLE 5
AMINO ACID COMPOSITION
OF SPRAY DRIED SHELLFISH WASTE PROTEINS
Sample
Dungeness crab protein
As received
Basis %
100% protein
Basis %
Shrill
As received
Basis %
E protein
100% protein
Basis %
Casein (M
100% protein
Basis
Lysine*
Histidine*
Arginine*
Aspartic Acid
Threonine*
Serine
Glutamic Acid
Proline
Glycine
Alanine
Cystine
Valine*
Methionine*
Isoleucine*
Leucine*
Tyrosine
Phenylalanine*
Tryptophan*
Total
*essential
5.4
2.21
5.5
10.3
3.57
2.7
12.3
4.33
4.2
4.6
0.24
5.5
1.97
4.7
6.6
4.0
4.07
1.0
6.35
2.60
6.47
12.1
4.20
3.18
14.5
5.10
4.94
5.41
0.28
6.47
2.32
5.53
7.78
4.70
4.80
1.18
97.9
6.24
2.22
6.04
6.46
2.93
3.51
13.3
3.40
5.63
5.35
not deter-
mined
4.21
1.95
3.87
6.10
2.70
3.78
0.55
8.34
2.97
8.06
8.63
3.91
4.69
17.8
4.54
7.52
7.14
-
5.62
2.60
5.17
8.14
3.61
5.05
0.73
104.52
6.02
2.31
2.41
4.45
3.81
5.88
21.90
15.71
1.16
1.47
not deter-
mined
7.91
2.75
3.91
11.07
2.72
5.46
1.00
99.94
33
-------
crab and shrimp waste proteins in comparison with casein (6). It was
found that the compositions of the two shellfish waste proteins were
quite similar although determined by two different laboratories using
different procedures. They both compare favorably with casein in
total essential amino acid content. The percentages of arginine and
isoleucine are significantly higher for the shellfish proteins while
casein shows higher values for valine and leucine.
Feeding tests have been conducted on rats using both the shrimp and
crab waste proteins. Both show marked deficiency in sulfur-containing
amino acids which can be corrected by supplementation with either
cystine or methionine. Otherwise the shellfish waste proteins were
found to be equal to casein in nutritional value and there were no toxic
effects noted.
A sulfur balance on crab waste and on the extracted protein indicated
that most of the sulfur in the waste is still present in the spray dried
protein. It should be noted, however, that a very slight odor of hydro-
gen sulfide has been detected during neutralization of alkaline extracts.
Based on assays for cystine and methionine, only about half of the sulfur
found in the protein can be accounted for. It thus appears that sulfur-
containing amino acids were present before extraction at about twice
the level found by assay on the isolated protein.
Review of the literature (7)(8)(9){10) on effects of alkaline treatment
on methionine and cystine in proteins suggests that methionine should
be relatively stable in the treatment but that cystine can be largely
and irreversibly converted to lanthionine which presumably has no
nutritional value as a sulfur source. The exact mechanism for the
reaction is not clear but the overall effect is the rupture of disulfide
bonds with elimination of 1 atom of sulfur and recombination of residues
in a thio ether linkage.
Cystine: HOOC-CHNH -CH-S-S-CH CHNH -COOH
£* £t £t L*
Lanthionine: HOOC-CHNH -CH-S-CH CHNH -COOH + S
& £ Lt Ci
The form of the eliminated sulfur was not clearly established.
Normally, there is an equilibrium between cystine and cysteine
residues in proteins determined by the presence of oxidizing or
reducing conditions in the system. The formation of cysteine with
free sulfhydryl groups may be an intermediate step in lanthionine
reaction. If it is not, or if the sulfhydryl group can be blocked from
combining as thio ethers, the presence of a reducing agent should
34
-------
be beneficial in preventing lanthionine formation. Sulfite ion, either
by shifting the equilibrium toward cysteine or by blocking recombina-
tion through formation of s-sulfo cysteine groups might serve this
purpose.
Experiments by Food, Chemical and Research Laboratories, Inc.
indicate that the presence of sodium sulfite during extraction does
exert beneficial influences. There were noted in increased extraction
rate (rupture of disulfide crosslinks?) and in improved color and odor
of the extracted proteins. Analytical results suggest that reduction in
extent of cystine destruction may also have been achieved.
Cystine determinations (6) showed 1.05% in Dungeness crab protein
extracted in the presence of sodium sulfite and 0. 23% in Dungeness
crab protein extracted in the absence of sodium sulfite. It would
appear that cystine destruction was reduced in the sulfite experiment.
Factors Determining Rate of Protein Extraction
Rate studies have been conducted on extraction of Dungeness crab and
shrimp wastes using two different procedures. In one, the rate at
which protein concentration approaches an equilibrium value is
measured in a batch treatment at constant alkali concentration and
temperature. The procedure has been found most useful to characterize
the behavior of different wastes and to determine effects of pretreatment,
alkali concentration and temperature. Calculation of rate constants
assumes that the rate of change of protein concentration at the inter-
face between shell particles and ambient liquid is proportional to a
driving force equal to the difference between protein concentration in
shell interstices (P ) and that at the interface (P.).
S X
d P. /dt = K(P - P.)
i si
Further assumptions are that P. is equal to the protein concentration
in the ambient liquid and P is equal to the total unextracted protein
dissolved in a constant interstitial volume equal to the water content
of the moist shellfish waste. Values for P can thus be calculated
o
from those for P. and numerical integration can be employed to obtain
the rate constant. This is equal to the slope of the line:
log, rt(P - P.)/P , . . ..versus time. Typical data plots are shown
"10 s i s(original) 'r
in Figure 5 for shrimp and Dungeness crab waste using different
extraction conditions.
It was found that both shrimp and crab wastes show an initial period
of very rapid extraction amounting to 30% to 50% of the total protein
35
-------
0
-•
-
c
«c
O
-
1.75
1.50
1.25
0.75
EXTRACTION RATES for SHE LFISH WASTES
Dungeness 1% NaCH, 60 C
Dungeness 0.25% NaOH + Na,SO_
553C
Dungeness 1.2% NaOH, 80C
O Shrimp 1% NaOH, 60°C
75 100
TIME IN MINUTES
125
150
FIGURE 5
-------
followed by a rather sharp break and a slow extraction period which
fits the diffusion mechanism outlined above. This is undoubtedly an
oversimplification of the true mechanism, but serves to give a
numerical index of the waste behaviour. It is noted that rate constants
obtained for shrimp waste are considerably higher than for Dungeness
crab shell particles of the same size, probably reflecting the density
of the shell. It is also noted that temperature effects are higher than
would be expected for strict diffusion dependence of the rate constants.
Note: Curves for Dungeness crab in 1. 0% and 1. 2% NaOH in Figure 5
are at nearly equal alkali concentrations but with 20° centrigrade
difference in temperature. This suggests chemical activation such
as rupture of bonds between chitin and protein as being involved in
the process. Based upon pilot plant extraction runs alkali concentration
does not appear to be an important variable. Sufficient alkali to
satisfy the base binding capacity of the protein is necessary. This
appears to be about 10 grams of NaOH per 100 grams of protein. Also
a pH level of 12. 5 or higher appears necessary for the extraction since
sodium carbonate solutions with concentrations up to 5% are relatively
ineffective. Addition of sodium sulfite to the alkaline extraction liquor
may have a specific effect in increasing the extraction rate as well
as other beneficial effects.
The other procedure for study of extraction rates has been the deter-
mination of protein levels in elution from percolation experiments
in a fixed bed diffuser type reactor.
Results from this type of experiment are more difficult to interpret
because more variables have to be considered such as flow rate and
alkalinity. Alkalinity is not constant during the extraction because
unextracted protein absorbs alkali during early stages of the experi-
ment. A mathematical analyses of the elution process has been de-
veloped (ll)(12) which allows prediction of elution rates from rate
constants determined by the "approach to equilibrium" procedure.
The treatment would be generally applicable to any fixed bed extraction
process which is diffusion controlled and may prove to be of value
should such types of processing become indicated.
C. P.P. and B. O. D. of Shellfish Wastes
In previous reporting, C. O. D. values for wastes were estimated for
chemical compositions assuming theoretical values for combustion of fat,
carbohydrates and protein. It is of interest to compare these with
values determined by the usual dichromate oxidation procedure (13).
37
-------
C. O.D. values were obtained on samples of shrimp waste, crab waste,
chitin isolated from shrimp waste by alkali and acid extraction and
protein isolated from crab waste by alkali extraction and isoelectric
precipitation. Data are presented in Table 6.
Values found are somewhat higher than those used in earlier reports.
They would indicate an even higher present pollution load to the harbor
but do not significantly affect estimates of abatement by the by-product
recovery process.
While C. O. D. values give a measure of the oxygen consumed in
complete oxidation of organic matter it is of interest to determine
the actual extent and rate of organic breakdown by micro-organisms.
Normally, B.O.D. values are determined by 5 day incubation of very
small waste samples in water with added mineral nutrients seeded
with micro-organisms normally present in receiving waters. The loss
in dissolved oxygen is determined for the 5 day period and is taken
as a measure of the oxygen consuming capacity of the waste sample.
With solid shellfish wastes there is no a priori reason to assume that
wastes would be entirely consumed in 5 days. The organic matter
(chitin and protein) is distributed throughout a more or less dense
shell matrix which may be only slowly attacked by micro-organisms.
Further, the digestion of chitin requires special enzyme systems
(chitinases) that may not be present in predominating micro-organisms.
To investigate some of these factors,studies of the rate of oxygen
consumption by shrimp and crab shell have been conducted. To permit
use of larger samples and minimize variation due to their heterogeneous
character, experiments were conducted using 5 liter volumes of seeded
dilution water and about 200 mg solid waste. Dissolved oxygen in the
closed system was determined at several elapsed times up to 120 hours.
A Yellow Springs Instrument Company Model 54 Oxygen Meter was
used.
Results are presented in Figure 6. For comparison, weights of waste
used are shown on a dry basis. With 52 mg of shrimp waste the rate
of oxygen consumption is very low at 120 hours.
The dissolved oxygen consumed was (8. 5 - 3. 9) (5) equal 23. 0 mg for
(52) (0. 68) = 35. 2 mg of chitin plus protein. This would be a 5 day
B. O. D. of 23/35. 2 = 0. 653 mg 0 per mg of organic matter or 48%
L*
38
-------
TABLE 6
C.O.D. VALUES OF SHELLFISH WASTE
Weight
Sample mg
Shrimp Waste
»» i»
?» 11
Crab Waste
» )>
>5 1>
Shrimp Chitin
»» >5
>» >»
Crab Protein
« »>
?» 59
101
110
101
109
101
112
19.5
27.0
20.5
10.2
10.2
10.2
Solids
%
25.9
25.9
25.9
67.5
67.5
67.5
93.1
93.1
93.1
100.0
100.0
100.0
CaCO3
dry basis
%
32.0
32.0
32.0
50.0
50.0
50.0
< 1.0
< 1.0
< 1.0
< 1.0
< 1.0
< 1.0
Chitin+Protein
dry basis C.O.D.
% mg 02/mg Organic Matter
68.0
68.0
68.0
Average
50.0
50.0
50.0
Average
100.0
100.0
100.0
Average
100.0
100.0
100.0
Average
1.27
1.42
1.44
1.37
1.03
1.12
1.05
1.06
1.22
1.24
1.27
1.24
1.40
1.40
1.37
1.38
39
-------
-
c:
a
I
2
UJ
FIGURE 6
OXYGEN CONSUMPTION BY SHELLFISH WASTE
48 60 72
TIME IN HOURS
108 120
-------
of the C. O. D. ratio in Table 6.
With 101 mg of crab waste some oxygen was still being consumed at
120 hours. The 5 day B.O. D. would be (8.70-2.35)(5) equal 31. 8 mg
for 50. 5 mg of chitin plus protein or 0. 63 mg 0 per mg of organic
matter. The ratio of B. O. D. to C. O. D. wouldlje 0. 59.
Soluble Waste Losses in Shrimp and Crab
Fresh raw shrimp obtained from Kinnear and Wendt in Kodiak on
March 9, 1971, were frozen and sent to the Seattle Laboratory by
air for immediate processing.
In one experiment following practice with old style (Laitram Model A)
peelers, 4. 0 Ibs of thawed raw shrimp were peeled by hand using
4.25 Ibs of water for waste preparation. The recovered meat was
boiled 2 minutes in water, cooled in water and collected on a 40 mesh
screen. Cooking and cooling waters were combined. The solid waste
was washed by slurrying twice in water and draining on a 40 mesh
screen. The shell wash water and original peeling water were com-
bined. Weights, total solids, suspended solids, C. O. D. , B. O. D.
and nitrogen were determined on significant fractions and material
balances were computed. Data are shown in Table 7.
The yield of picked meat was 24. 1% of live weight which is higher than
usually obtained with mechanical peelers (18%). B. O. D. andC.O.D.
values on peeling and wash water and cooking and cooling waters were
very high, reflecting the use of only 0. 5 gals, of total processing
water per Ib of raw shrimp as opposed to about 7. 5 gals, per Ib of
shrimp as an average of operating practice at Kodiak. This suggests
that considerable reduction in water consumption might be affected
by more efficient peeler design.
The percent of the waste solids recoverable in washed shell was only
60% (57. 2% of the C. O. D. ). A surprisingly high loss of waste solids
(28. 7%) and of C. O.D. (33. 1%) occurred in peeling and washing water.
This should be compared with results obtained on shrimp which were
steamed 2 minutes before peeling.
The shrimp were steamed 2 minutes before hand peeling. Shell and
process waters were handled as in the previous experiment. Data
are presented in Table 8.
The yield of meat was 25. 8% of the live weight, again showing im-
provement over mechanical peeling. C.O.D. and B. O.D. values
41
-------
TABLE 7
WASTE DISTRIBUTION IN SHRIMP PROCESSING
A. Raw Peeling
Analysis
Sample
Raw shrimp
Washed shells
Cooked meat
Cooking and
cooling water
Peeling and
washing water
Sample
Raw shrimp
Washed shell
Cooked meat
Cooking and
cooling water
Peeling and
washing water
Weight
grams
1,815
1,292
439
1,046
6,248
grams
467
236
87
44.5
113
Total
Solids
25.7
18.3
19.8
4.26
1.81
Solids
total
100
50.5
18.6
9.5
24.2
Suspended
Solids
0.43
0.49
Distribution
waste
60.0
11.3
28.7
C.O.D.
ppm
304,000
173,000
267,000
36,300
23,900
grams
552
224
117
38
130
5 Day
B.O.D. N
ppm ppm
18,000 5,850
9,800 2,180
C.O.D.
waste
57
10
33
42
-------
TABLE 8
WASTE DISTRIBUTION IN SHRIMP PROCESSING
B. Peeling after Steaming
Analysis
Sample
Raw shrimp
Washed shells
Cooked meat
Cooking and
cooling water
Peeling and
washing water
Sample
Raw shrimp
Washed shells
Cooked meat
Cooking and
cooling water
Peeling and
washing water
Weight
grams
1,818
1,325
470
2,563
5,865
grams
467
267
101
Total Suspended
Solids Solids
25.7
20.1
21.4
1.58 0.37
1.24 0.63
Distribution
Solids
total waste
100
57.2 70.2
21.6
C.O.D.
304,000
173,000
267,000
19,200
17,500
grams
505
254
136
5 Day
B.O.D. N
ppm ppm
9,600 2,500
7,800 1,680
C.O.D.
waste
70
40.5 8.7
72.8 15.6
10.7
19.1
34
84
10
23
43
-------
for process waters were considerably lower than for raw peelings.
Total soluble losses were 30% of the initial solids as compared
with 40% for raw peeling. It appears that the initial steaming
coagulates and prevents loss of some solubles. In this experiment
70% of the initial solids or C. O. D. was recovered in the washed
shell.
Three whole live Dungeness crab were brought to the laboratory from
Westport, Washington. They were cooked 15 minutes in 2 liters of
water using 50 grams of salt. The cooked crab were drained hot,
then cooled in a refrigerator and weighed. After cooling, the crab
were butchered and weights of different portions were determined.
These were then analyzed for solids, C. O. D. and other factors.
Data are presented in Table 9.
The yield of picked meat amounted to 31. 2% of live weight which
is higher than normal plant practice. Total solids recovered, in all
fractions, after correction for added salt, amounted to 27. 2% of live
weight indicating full recovery. Solids in waste fractions amount to
74. 6% of the total with only 2. 4% in picking wash water. The remainder
would be recoverable either as butchering waste to be processed with
scrap fish or as shell.
C. O. D. values as Ibs per 100 Ibs live weight for backs and picking
line shell have been calculated from previous experimental data
reported in Table 6. Values for other waste fractions are calculated
from present data. The total C. O. D. load in all waste fractions
amounts to 1 5. 8 Ibs of C. O. D. per 100 Ibs of live weight. Of this,
5. 9 Ibs or 37.4% would be recovered as picking line shell and 7.9 Ibs
or 49. 8% as backs and viscera. The remainder 2. 0 Ibs or 12. 8%
would be lost in cooking and wash water.
Preceding data indicate that pollution abatement from crab processing
by recovery of shell and viscera is considerably more effective than
collection of solids in shrimp processing. Parallel experiments
on King and Tanner crab have not been conducted but there is no
reason to expect that significantly different values would be obtained.
In another experiment, 3 Dungeness crab were butchered live and
only legs and bodies were cooked. Data for this experiment are
presented in Table 10. They are in substantial agreement with the
whole cooked crab experiment. Solids recovered were 27. 5% of live
weight. Total C. O. D. of waste was 15. 35 Ibs C.O. D. per 100 Ibs
of live weight of which 13. 54 Ibs or 88% is recoverable in backs,
viscera and picking line shell.
44
-------
TABLE 9
COOKING WHOLE CRAB
Live
Weight
Samole grams
Whole crab
No. 1 1,090
No. 2 1,045
No. 3 965
Total 3,100
Legs and
Bodies
Backs
Viscera
Picking Line
Shell
Leg Meat
Body Meat
Cooking Water
Viscera + Wash
Water
Picking Water
Total
Cooked
Weight
grams
982
973
900
2,855
1,743
190
530
615
563
404
2,150ml
2,280ml
4,000 ml
Total
Solids C.O.D.
% ppm
(27.2%
of live
weight)
60.2
55.8
22.6
21.4
2.2 13,600
6.3 80,400
0.5 8,400
Solids C.O.D.
%of Ib/lOOlbs
grams total Live Weight
114.3 13.6 ( 1.96)
353.0 41.8 ( 5.90)
127.0 15.1
86.5 10.3
47.3 5.6 0.94
(mostly
salt)
143.7 17.1 5.90
20.0 2.4 1.08
891.8 105.9 15.78
45
-------
TABLE 10
LIVE BUTCHERED CRAB
Sample
Whole crab
No. 1
No. 2
No. 3
Total
Backs
Viscera +
Water
Cooking
Water
Picking
Waste
Wash Water
Leg Meat
Body Meat
Total
Live Cooked Total
Weight Weight Solids C.O.D.
grams grams % ppm
815
923 1,413
(legs & bodies)
980
2,718 27. 5 of
live weight
183 57.8
2,280 5.3 67,200
2,520ml 1.1 7,600
540ml 55.8
4,000 ml 0.3 7,600
465 23.3
322 21.6
Solids C.O.D.
%of Ib/lOOlbs
grams total Live Weight
106 14.2 ( 2.07)
121 16.2 5.60
28 3.7 0.70
302 40.3 ( 5.87)
12 1.6 1.11
109 14.6
70 9.4
748 100.0 14.35
46
-------
Salmon Offal
Samples of salmon offal as discharged into Kodiak Harbor by Columbia
Ward Fisheries and B & B Fisheries were sent to the laboratories in
frozen condition. This material was used for processing studies.
A sample of thawed waste was ground in a home-size garbage disposal
unit without added water. The gurry obtained was analyzed for solids,
fat,protein and ash. Results were as follows:
Solids 20. 6% (as received)
Fat 30. 3% (dry basis)
Protein 40.0% (dry basis)
Ash 21.0% (dry basis)
A mixture was prepared from 1, 109 grams gurry, 200 ml 10% NaOH
and 691 ml water. This was heated for 1 hour at 60° C with a mechan-
ical stirrer. The solid residue was then collected on a filter, washed
with 100 ml of water and dried. Yield 38. 8 grams. It consisted of
fine bone fragments with a small amount of clam and mussel shells.
The extract solution (1, 800 ml) contained 8. 57 mg nitrogen per ml
or 1 5. 4 grams total. This is equivalent to 96. 5 grams of protein
(N x 6. 25) or 100% of that calculated for the starting material.
A 50 ml sample of the extract solution was titrated conductimetrically
with standard HC1. It showed an alkali consumption of 18 grams of
NaOH per 100 grams of protein. Also, about 37% of the added alkali
was unconsumed. Accordingly a second extraction was conducted in
the same manner with 0. 75% NaOH instead of 1% as used before.
Titration of the resulting extract showed a slightly lower alkali
consumption per unit of protein with 21. 5% of the added alkali un-
consumed. Protein in the extract liquor was 107. 8 grams or 98%
of the initial protein.
Extract liquors were adjusted to pH 4. 0 with dilute HC1 yielding a
good protein precipitation which filtered readily with a clear filtrate.
Additional grab samples of salmon waste collected during the run at
Kodiak were sent to Seattle frozen in 3 gal. plastic pails. They varied
widely in solids content from nearly 0% to about 21%. A sample
containing a maximum of solids was ground in a garbage disposal unit
and analyzed for solids yielding 20. 7%. The dried material was
analyzed with results as follows:
47
-------
Fat 30. 3%
Protein 42. 8%
Ash 21.0%
Calcium 3. 4%
Phosphate 10.5%
The ground wet material was slurried with 700 ml of 1% NaOH and
digested for 1 hour at 60° C using mechanical stirring. It was then
filtered yielding 1, 800 ml of extract and 38. 8 grams of residue (dry
weight). The extract contained 53. 5 mg protein and 27. 2 mg of fat
per ml. A material balance for the extraction shows 98% recovery
of protein and 70% recovery of fat with 81% of the ash in the dried
residue.
The extract was adjusted to pH 4. 0 with HC1, to cause isoelectric
precipitation of protein, and filtered. Analyses of the filtrate showed
the following:
Total volume 2, 085 ml
B.O. D. 11,750 ppm
C.O. D. 11,920 ppm
Protein 21. 4 mg/ml
Phosphate 800 ppm
Protein recovery by isoelectric precipitation was found to be only
53. 5%.
This is much lower than recoveries which have been obtained from
alkali extracts of crab and shrimp waste which consistently show
85% to 90% recovery. Attempts to improve recovery by precipitation
of a polyphosphate complex or by lime addition were only slightly
effective (visual appraisal). It was concluded that autolysis of the
waste by action of visceral enzymes was probably responsible. It is
also possible that a substantial part of the nitrogen in the filtrate was
nonorganic nitrogen. This is supported by B. O. D. and C. O. D. values
which are only about 1/2 of values calculated from the assumed protein
content.
For comparison with data on Kodiak salmon waste, a sample of waste
from a La Conner, Washington operation was subjected to similar
treatment.
48
-------
Analyses of a ground slurry prepared as with Kodiak waste was as
follows:
Solids 21. 8 % (as received)
Fat 20. 4 % (dry basis)
Protein 61.2 % (dry basis)
Thirty two Ibs of this waste was extracted with 1% NaOH for 1 hour at
60° C and passed through a 40 mesh screen. Thirty four Ibs of extract
and washings and 162 grams (dried) of residue were obtained. The
residue contained 5. 0% nitrogen (31. 3% protein) and 62. 9% ash. It
amounted to only 5. 1% of the original solids.
The extract contained 16. 3% solids, 110. 6 mg protein per ml and
33. 5 mg fat per ml. Total recoveries of 88% of original protein
and 80% of original fat are indicated. These results probably reflect
sampling error since the ground slurry was not homogenous and there
should be no losses in the digestion treatment.
Precipitation tests were conducted on small aliquots of the extract
with results even less satisfactory than on Kodiak salmon waste.
Experiments on fat removal using a continuous Westplalia separator
were more successful. After adjusting to pH 6. 0 and passage through
the separator the fat content of the extract was reduced from 3. 35%
to 0.48%. Small scale laboratory centrifuge tests indicated that
better separation might have been achieved at pH 8. 0.
To summarize results obtained on salmon waste to date, it is con-
cluded that alkali digestion followed by isoelectric protein precipitation
or precipitation of protein as a phosphate complex or a calcium
proteinate will not achieve a reasonable level of pollutant removal
from effluents. The alkali digestion does appear to be of value in
homogenizing the waste so that solid residues (bond, etc. ) can be
removed on 40 mesh screens and so that fat removal can be accom-
plished by centrifugal treatment. This refining can be conducted at
relatively high total solids content (16%) which is not far below that
of the dewatered waste (20% to 21%).
Evaporation of the refined extract to about 50% solids using triple
effect evaporators would yield a product similar to the "concentrated
fish solubles" already an article of commerce. There would be no
liquid effluent from the process. The product would be biologically
49
-------
stable and could be shipped in drums or tanks to market areas.
To estimate the effectiveness of solids removal by screening, recourse
is again taken from a La Conner, Washington operation with which we
are familiar. This cannery operated during July, August, and Septem-
ber, 1970, primarily on silver salmon. Due to the larger size of these
fish only about 68 Ibs are processed per 48 Ib case as compared with
83 Ibs of Kodiak operation on Bristol Bay red salmon. Heads and
roe are separated from the waste during butchering and are separately
handled for oil and caviar production. Spent heads are hauled to a
dump. Remaining solids are collected with a 20 mesh flat type screen
and are sold without further treatment for pet food manufacture.
Effluent from the screen is discharged into the Swinomish Slough, a
tidal estuary, discharging into Padilla Bay or Skagit Bay depending
on the tidal flow.
A summary of the season's operations shows the following:
% of fish (live weight)
Fish packed 71.0
Eggs packed 3. 0
Oil produced 0. 5
Solid wastes to dump 5. 7
Waste sold as pet food 14. 1
Waste lost to sewer 5. 7
While the waste lost to the sewer was 5. 7% of fish processed it was
5. 7/29 = 19. 6% of the total waste, i. e. of the fish not packed in the
can.
50
-------
SECTION VIII
MARKETS
As the isolation of recoverable by-products from shellfish wastes is
a new process the salability of these materials in the quantities
anticipated must be considered thoroughly.
The proposed plant will be capable of producing at least 7 million Ibs
of shellfish protein plus other fisheries products. The shellfish
portion will have a protein content of at least 90%, and ash content
of less than 5% with the remainder being moisture.
Feeding tests have shown this protein to be of high quality, and ex-
ceedingly palatable to pets.
According to one major pet food manufacturer, who conducted exten-
sive feeding tests on cats, it is a preferred protein. This manufacturer
has indicated a desire to purchase at least 5 million Ibs of the shell-
fish protein at from $0. 12 to $0. 20 per Ib F. O. B. Kodiak.
As a protein competitive with fish meal, which is the largest volume
high grade protein sold, the following comparisons can be made:
There were 458,000 tons of fish meal (14) available for sale in the
United States during 1970, at an average price of $196. 50 per ton
for anchovy (65% protein). This is $300.00 per ton ($0. 15 per Ib)
on a 100% protein basis. While 90% protein material calculates to
be $270. 00 per ton or $0.135 per Ib on an equivalent basis, the palat-
ability, low oil and ash content will make the selling price at least
$0. 15 per Ib, with a price floor equivalent to fish meal protein.
Production of 3, 500 tons per year of protein will represent 0. 8% of
the total fish meal available for sale in the United States.
Because of the carotenoid pigment astaxanthin, which gives shrimp
and crab their red color, there is great interest in the use of ex-
tracted shellfish protein for hatchery trout feed. This pigment when
fed to hatchery trout causes their flesh to turn salmon color, a
desirable effect. Presently limited quantities of dried shrimp meal
are being sold to trout hatcheries for this purpose.
A concentrated supply of protein plus astaxanthin will command a
premium price over other protein sources.
51
-------
A large market exists for food quality shrimp protein. Present selling
price for this material is $0. 90 per Ib on a bond-dry basis. The pro-
posed plant is not being designed to manufacture products for human
consumption, however, it is felt that by proper handling certain portions
of the waste load can be converted to food grade products provided
clearance from the Food and Drug Administration can be obtained.
The use of shellfish protein has not been fully investigated as an
industrial chemical.
There are approximately 50 million Ibs of soya isolate (90% protein)
consumed each year in the United States at a selling price of from
$0. 22 to $0. 24 per Ib (15). The paper coating field requires 70% of
this market while the paint, adhesive, ink and miscellaneous industries
consume the rest.
Limited tests with a regional ink manufacturer have shown that they
can replace soya isolate with deoderized shellfish protein. Should
this be the case in the paper coating field the potential profit of this
plant could rise by 30% to 35%. Further development work must be
done to establish these markets.
The markets for salmon oil are well established with fish oil presently
selling for $0. 1015 per Ib. Over 200 million Ibs of fish oil were pro-
duced in the United States in 1970 (14). Production of 300, 000 Ibs at
Kodiak is an insignificant increase.
The market for fish solubles is also well established. There were
90, 700 tons (14) produced in the United States during the first 10
months of 1970. These solubles sold at an average price of $51. 90
per ton F. O. B. East Coast plants.
The production of 2,000 tons represent 2.7% of the United States produc-
tion. Using $30.00 per ton as an estimated selling price F. O. B.
Kodiak and an indicated freight cost to Puget Sound ports of $20. 00
per ton, the F. O. B. Puget Sound price becomes $50.00 per ton.
Other than a small production of tuna solubles produced at Astoria,
Oregon, there are no other local sources of solubles available to
Northwest consumers. Northwest consumers import from California,
Gulf or East Coast suppliers. The freight to the Northwest from these
points would place the product in a preferred price position.
The garden specialty market can readily absorb the 200 tons of fish
bone meal which will result from the production of the solubles.
52
-------
The only other product requiring a market is the 6, 600 tons (bone-dry
basis) of chitin-CaCO_ complex. Because of the distance between
Kodiak and the Continental United States the cost of transportation
appears to be a problem. To help resolve this problem this material
is to be pressed to 50% solids with a bulk density of 60 Ibs per cu
ft. Using $10. 00 per ton bone-dry basis F. O. B. Kodiak the complex
can be shipped to the Pacific Coast ports at a delivered price of $50. 00
per ton of solids. This delivered price could make conversion of the
complex to chitin and its derivatives economically possible.
There are several companies looking at the possibility of building a
plant in the Puget Sound area to convert the complex to chitin de-
rivatives. It is likely that such a plant will be built once a source
of raw materials is guaranteed. The Alaska market for the complex
exists as a liming agent - soil amendment. Test runs at the Palmer,
Alaska, experiment station (16) show that this material is useful on
the acid soils of Alaska.
A price of $10. 00 per bone-dry tone F. O. B. Kodiak might induce the
Alaska agriculturists to use the nitrogen-phosphorous-calcium
containing complex on their gardens and farms.
Ready markets for the production of this plant exist at attractive
economic returns. Chitin derivatives have huge potential world
markets and if made competitive with other soluble polymeric
materials can sell in the range of $0.65 to $1.65 per Ib. Competitive
products are carboxymethylcellulose, polyvinylpyrrolidine, poly-
acrylamides and others. The markets could be proved if isolation
of chitin at Kodiak were possible. Work on this project should be
initiated.
53
-------
SECTION IX
PROPOSED FACILITIES
The proposed facilities consist of: waste collection at the shrimp,
crab and salmon processors; transportation of the waste material
to the by-product recovery plant; and the by-product recovery plant.
Kodiak has limited sites available for the by-product recovery plant.
The sites proposed by Kodiak were inspected. Two sites located in
close proximity to the processing plants were too small. A third
site located 4 miles from the processors would not permit easy
disposal of liquid products produced in the by-product recovery.
The site selected and recommended is located on Near Island directly
opposite the shrimp, crab and salmon processors (Figure 7). The
by-product recovery plant is to be located on Kodiak city-owned land.
The selected site must be no less than 2. 5 acres. The site must
lend itself to the construction of secondary treatment facilities.
The site must be readily accessible for transportation of the waste
and recovered products.
Trucking of waste is estimated to be more costly than barging. The
use of barges as holding tanks for shrimp waste reduces the invest-
ment required for storage of shrimp waste prior to transporting
to the by-product recovery plant.
The barging of the waste from the processors to the by-product
recovery plant will be handled by long term contract. The barge
contractor will supply a minimum of 12 small flat barges and the
required power equipment. The by-product recovery plant will
supply containers permanently mounted on the barge. The processors
will supply the required holding tanks and collection systems within
their own plant. The barge contractor will handle the personnel
transportation to the Near Island site.
A barge with free draining containers will be located at each shrimp
processor. The shrimp processor will pump his wet shrimp waste
directly into the barge. The barge will be removed and replaced once
or twice a day as production requires. No holding tanks for shrimp
waste will be required at the shrimp processing plant.
Crab picking line waste will be dewatered by the crab processor and
held in holding tanks adjacent to the barge transfer area. No
55
-------
Ul
a-
DEPTH 20' AT END
PROPOSED
8" OUTFALL
PROPOSED
BY-PRODUCT
RECOVERY PLANT
PROPOSED
TRESTLE & DOCK
MAP
LOCATION & TOPOGRAPHY
FIGURE 7
-------
significant deterioration of wastes in 12-24 hours is anticipated.
The holding tank will be emptied by gravity into the barge. Barge
pickup will be once or twice a day as production requires.
Scrap fish from shrimp processing and crab butchering waste will be
held in holding tanks adjacent to the barge transfer area. Scrap fish,
crab butchering waste and salmon fisheries waste may be combined
and held in the same holding tank. Pickup will be once or twice a
day as required.
A pier and crane will be built at the Near Island site (Figure 8). This
pier will accommodate 5 small barges. The pier will be equipped
with a 5 ton crane. The pier will accommodate a 3 ton capacity fork
lift.
The barges will be unloaded by a pneumatic unloading system. The
pneumatic unloading system will transfer the waste from the barges
into holding tanks at the by-product recovery plant. A similar system
will be used to transfer finished bulk product directly from the by-
product recovery plant into cargo vans on barges at the pier.
A 500 KW diesel generator and 600 HP packaged boiler will be located
at the recovery plant. These units will use No. 2 diesel as fuel. A
plant and instrument air system is included.
The by-product recovery plant will be located in a steel and masonry
building 120 ft wide by 180 ft long. The building will be on 2 levels
to take advantage of the natural contour of the land. The building will
have a concrete slab floor. Within the building are the sanitary
facilities, lunchroom, office, laboratory and boiler room (Figure9).
Fresh water for the plant will be obtained from the roof of the building
and from a holding pond constructed approximately 300 ft from the
building. The water will be treated as required. The liquid effluent
from the recovery plant contains less than 5, 000 Ibs per day of B. O. D.,
based on best estimate. The dissolved material is essentially protein.
Secondary treatment of the plant effluent is not considered at this time.
An outfall to -20 ft should be installed into the more swiftly moving
waters of the narrows.
The processing facilities would consist of: a process line for scrap
fish, crab butchering waste and salmon fisheries waste; a process
line for the shrimp waste; and a process line for the crab picking
line waste.
57
-------
vl
- X
*ff Dolphin
hicca,
}n
•0
fe L
30-O" i
Fender P//G
D
\
Brace
NOT FOR CONSTRUCTION
NOT TO SCALE
/-
f
12
-^
^_bai^^@L_lO^O^_8O '-_O^
PLAN
jtA
TT~ [I
SECTION
u
FIGURE 8
DOCK & TRESTLE
FOR THE PROPOSED BY-PRODUCT RECOVERY PLANT
58
-------
vO
•n
m
O
3D
O
m
T>
m
2>
P=PUMP
C = CONVEYOR
S = SURGE TANK
CE = CENTRIFUGE
- NEUTRALIZING
TANK
BY-PRODUCT RECOVERY PLANT
PROCESS BUILDING
LABORA
TORY
FtOOH ELEV. 40.00
VACUUM
8
CRAB
SHELL
PRODUCT
SHRIMP
SHELL
PRODUCT
r /"\ /—\
5 (NaOrt mcij
;., V_>n v—^/
RAMP UP
NOT FOR CONSTRUCTION
FIGURE 9
-------
The combined scrap fish, crab butchering waste and salmon fisheries
waste will be fed to the process unit from a 12 ft square x 14 ft high
tapered bottom tank (Figure 10). A variable rate screw conveyor will
feed a grinder. The waste after grinding is conveyed to a 5 ft diameter
x 20 ft long cooker where 50% NaOH is added to solubilize the protein.
The quantity of NaOH added is equivalent to 1% by weight of solids.
The cooker is maintained at 60°C.
The cooker product is pumped to a mixer equipped tank where 31%
HC1 is added to reduce the pH to 8. 5. The pH adjusted waste is centri-
fuged first to remove the oil and then to remove bone. The oil is
collected in drums for shipment. The bone is dried to 6% moisture
and bagged for shipment.
The liquid from the bone centrifuge is reduced in moisture content to
50% in a triple effect evaporator. The 50% moisture material is loaded
into drums for shipment. A solids content of 50% has been arbitrarily
chosen to equal that of commercial fish solubles. The solids content
could be varied to meet trade preferences.
The dewatered shrimp waste will be fed to the process unit from two
1 2 ft square x 14 ft high tapered bottom tanks (Figure 11). A variable
rate screw conveyor at each holding tank will feed a grinder. From
the grinders the waste is conveyed to parallel reactors. Each reactor
line has two reactors 5 ft diameter x 20 ft long.
In the reactors the waste is treated countercurrently with 50% NaOH.
NaOH is added at a rate equivalent to 1 Ib of NaOH for each 10 Ibs of
protein. The contact time in the reactor is about 1 hour. The reactors
are heated with steam and the exhaust from the diesel generator. A
water wash section is provided within the second stage reactor.
The solids product from both reactor lines is combined and conveyed
to a heated screw press where the deproteinized shrimp waste is
pressed into a cake with a moisture content of 50%. The pressed
cake is pneumatically conveyed either into storage or directly into
vans on barges at the pier. Stabilization by removal of protein should
permit storage and shipment of the material without significant
deterioration.
The NaOH-protein rich solution from both reactor lines is combined
with the NaOH-protein solution derived from crab shell and treated
in a mixer equipped tank with 31% HC1. The pH is reduced to 4. 0 to
precipitate protein. The slurry is filtered. The solids are water
60
-------
o
WASTE, from Barge
unloading System
Variable rate
Screw
CONVEYOR
50% Solids
50%
£.
P ^-—' Into 55 Gal. Drums
Steam Storage
Evaporator
31% HCI
from Storage
BONE MEAL
to Storage
Bagger
p Into 55 Gal. Drums
LEGEND
P = PUMP
C = CONVEYOR
S = SURGE TANK
R = REACTOR ( COOKER )
G = GRINDER
SCHEMATIC FLOW DIAGRAM
SCRAP FISH FROM SHRIMP PROCESSORS, CRAB BUTCHERING WASTE
& SALMON FISHERIES WASTE, PROCESSING UNIT
NOT FOR CONSTRUCTION
FIGURE 10
-------
EXHAUST
ro
Screen
•0-
Rootes
Blower
50% NaOH
Storage
G>
Storage
To CRAB SHELL
Processing
p
1 STAGE II
' i
P
50% HO
Deprotelnized
SHRIMP WASTE
Holding
TANK 1
Variable Rate
Screw Conveyor
Holding
TANK 2
Liquid to
Steam Heated Collector System
Roller Dryer
Neutralization
Tank
From CRAB SHELL
Processing
FILTRATE to
Collection System
To Wash Water PROTEIN
31% HCI
Storage
Collection System
DEWATERED
SHRIMP WASTE
in Barge
To VAN or
Storage
Variable Rate
Screw Conveyor
Bagger
to Storage
LEGEND
P = PUMP
C = CONVEYOR
S - SURGE TANK
R = REACTOR ( COOKER )
G - GRINDER
To FISHERIES WASTE
Processing
SCHEMATIC FLOW DIAGRAM
SHRIMP WASTE PROCESSING UNIT
NOT FOR CONSTRUCTION
FIGURE 11
-------
washed and conveyed to a steam-heated roller dryer where the protein
is reduced to 6% moisture. Dry protein is bagged for shipment. The
filtrate liquid from the screw press is collected and disposed of through
the outfall.
The dewatered crab picking line waste will be fed to the process unit
from a 12 ft square x 14 ft high tapered bottom tank (Figure 12). A
variable rate screw conveyor will feed a grinder. From the grinder
the waste is conveyed to the reactor section.
The reactor section consists of two 5 ft diameter x 20 ft long reactors
in series. In the reactors the waste is treated countercurrently with
an NaOH solution. NaOH is added at a rate equivalent to 1 Ib NaOH
to 10 Ibs protein. The contact time in the reactors is about 2 hours.
The reaction takes place at 60° C. The reactors are heated by steam
and diesel generator exhaust. A water-wash section is provided in
the second stage reactor.
The solids product from the reactors is conveyed to a heated screw
press where deproteinized shrimp is pressed into a cake with a mois-
ture content of 50%. The pressed cake is pneumatically conveyed
either into storage or directly into vans on barges at the pier.
The NaOH protein-rich solution derived from the crab shell is combin-
ed with NaOH protein-rich solution derived from the shrimp waste.
The combined steam processing is described in the preceding paragraphs.
63
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WASTE from Barge
unloading System
U50% NaOH /
Storage I
O
P
STAGE 1 STAGE II
~
0
p
Variable Rate
Screw Conveyor
Storage
Screw PRESS
50% H20
Deproteinlzed
CRAB SHELL
to Storage
LIQUID to
Collection System
G>
pH 12.5
NaOH Protein-rich Solution
to Neutralization Tank
LEGEND
P = PUMP
C = CONVEYOR
S = SURGE TANK
R = REACTOR ( COOKER )
G = GRINDER
SCHEMATIC FLOW DIAGRAM
CRAB PICKING LINE WASTE PROCESSING UNIT
NOT FOR CONSTRUCTION
FIGURE 12
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SECTION X
ECONOMIC CONSIDERATIONS
Based on the 1970 production figures, 13. 6 x 10 Ibs of shellfish solids
could be collected in, Kodiak. From this waste load, 8. 8 x 10 Ibs are
Q
shrimp and 3.9 x 10 are crab solids.
However, the number of peelers put into operation when this report
was written has increased by 75%. It is assumed in this study that
they will operate at the same rate per peeler the others did in 1970.
Therefore, there will be at least 15. 4 x 10 Ibs of collectable shrimp
solids available for processing.
Using an average of 38% recoverable protein/from shrimp and 30%
recoverable protein from the crab, 5. 8 x 10 Ibs of shrimp protein
and 1.2x10 Ibs of crab protein per year can be recovered by using
this process. The indicated market price for this protein is $0.15
per Ib F. O. B. Kodiak on a 100% solids basis making the market price
for this product $1, 050, 000.
6
The salmon waste of 1. 3 x 10 Ibs would produce 300, 000 Ibs of oil
worth $24, 000; 200 tons of bone meal worth $40. 00 per ton, or $8, 000;
and 900 tons of 50% solids salmon solubles worth $30. 00 per ton or
$27,000.
Crab butchering waste and scrap fish associated with the shrimp
trawls of 0. 87 x 10 solids would produce an additional 1, 600 tons
of solubles worth $48,000.
The residual chitin-CaCO_ complex of 6, 600 tons (dry) has a minimum
value of $66, 000 F. O. B. Kodiak for its lime value, and will be worth
more when markets open up for c hi tin as an industrial chemical.
The total worth of these products is $1, 223, 000 per year.
As it is anticipated that this facility is to be set up along the lines
similar to a local improvement district and will enjoy government
financing, it therefore is necessary to require the users to pay a
fee for waste disposal.
Many different formulae have been proposed for such fees throughout
the world. Some are based on B.O. D. , C.O. D., or total solids
while others are based on water handled.
65
-------
At Kodiak a reasonable fee should be equivalent to the annual cash
reserve required for 7-year depreciation of the plant. The 7-year
period was chosen in consideration of the erratic history and un-
certainties of the industry and commonly accepted engineering
practice for installations of this type. This amounts to $225, 000
per year and can be based on the number of pounds of collectable
solids handled by the plant at $0. Oil /lb dry basis.
This is estimated to be 20. 6x10 Ibs, and is summarized on Table 11.
The costs of operating the plant (are as follows and) are based on the
barge handling of waste to the Near Island site which will be donated
by the City of Kodiak. The direct manufacturing expenses as shown
on Table 12 amount to $692, 000 per year, and are based on a plant
investment of $1, 592, 000. Table 13.
The indirect expenses amount to $531, 000. They are figured on
20-year, 7% bonds, with interest paid at 8% on a $500, 000 line of
credit, a cash reserve for depreciation of $225, 000 per year and
consultant and management fees of $99, 000.
The estimated profit based on these figures will be $219, 700, which
is $5, 300 less than the disposal fee of $225, 000. This means that
this $219, 700 per year could be returned to the processors paying
the dumping fee in its entirety, as adequate provision has been made
by means of the cash reserve for depreciation to completely rebuild
the entire plant in 7 years or enlarge it as the industry grows.
An alternative use for this money would be to use part of the dumping
fee and part of the cash reserve for depreciation to build an industrial
sewer system to treat the processing waters not handled by this plant.
All costs estimated for this report are based on June 1971 prices.
66
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TABLE 11
.SALES/YEAR
Shrimp Protein
Crab Protein
Salmon Oil
Fish Bone
Fish Solubles
Chitin-CaCCL
5.8 x 106
1.2 x 106
3.0 x 105
200
2,500
6,600
Ibs
Ibs
Ibs
tons
tons
tons
INCOME FROM
@ $ •
@
@
@ 40.
@ 30.
@ 10.
DISPOSAL
15 =
15 =
08 =
00 =
00 =
00 =
FEE
$ 870, 000
180,000
24,000
8,000
75,000
66, 000
$ 1,223,000
Collectible Shrimp Solids
15.4xl06lbs @$ 0.011= $ 169,400
Collectible Crab Solids
3.9 x 106 Ibs @ 0.011 =
Collectible Salmon Solids
1.3 x 106 Ibs @ 0.011 =
Total Income $1,448,000
Total Costs 1,228,300
Profit Before Taxes $ 219,700
42,900
14,300
$ 226,600
(Use $ 225,000)
67
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TABLE 12
YEARLY OPERATING EXPENSES
Barge
Labor
Maintenance
Electricity
Heat
Chemicals
G & A
DIRECT
$ 132,000
179,800
50, 000
30, 600
58, 000
152,000
89,900
$ 692,300
Retire bonds 20
years $
Bond Interest
7%
Sales Costs
Management
Consultants
Op Capital,
interest @ 8%
Cash, reserve for
depreciation
INDIRECT
80,000
56,000
31,000
75,000
24,000
40,000
225,000
Total
$
$1,
531,000
223, 300
Plant Cost
$1,592,000
Operating Credit Line
$ 500,000
68
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TABLE 13
PLANT INVESTMENT - JUNE 1971 PRICES
(Based On 9-Month Engineering Design and Construction Schedule)
Major Process Equipment (all prices delivered Near Island)
NO. ITEM
2 Baggers
2 Centrifuges
20 Conveyors (installed)
2 Driers
1 Evaporator
1 FUter
4 Grinders
2 Mixers
19 Pumps
7 Reactors (blenders and cooker)
2 Screw Presses
17 Tanks and Vessels (erected)
SUBTOTAL
Other Major Equipment (all prices delivered Near Island)
600 HP Steam Generator with Boiler Feed water System and Treatment
500 KW Diesel Generator and Motor Control Center
Instrument and Plant Air Compressor and Tank
Water Treating Unit
Pneumatic Unloading, Dried Shell Transfer and Loading Astern
Installed Complete (less wiring)
Dock Crane
Sump Pump for Liquid Waste Collection System
Dust Collection System
Heat Recovery from Diesel Generator
Small Tools (includes 3 ton fork lift and welding equipment)
SUBTOTAL
Major Construction Items (Estimated)
Building
Pier and Approach Ramp
12 Containers for Barges (installed)
Fresh Water Pond and Transmission Line
Liquid Waste Outfall
SUBTOTAL
Instrumentation (for those items not included with equipment - installed)
Millright (equipment setting)
Electrical (labor and materials)
Piping (labor and materials)
Soils
Civil (included with individual items)
Painting, Plumbing, Carpentry (included with individual items)
TOTAL
Contingency (15%)
Engineering and Construction Management
Process Consultants
DOLLARS
5,800
56,000
31,000
46,000
28,000
17,000
7,200
1,200
18,400
108,000
80,000
34,200
29,200
64,500
3,500
2,200
84,200
2,500
3,500
10,700
8,000
30,000
152,000
82,000
54,000
14,400
14.100
DOLLARS
432,800
238,300
GRAND TOTAL
316,000
22,000
59,600
38,800
68,000
22,000
1,198,000
180,000
168,000
46,000
1,592,000
69
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SECTION XI
PRO FORMA BUSINESS STRUCTURE
The establishment of a pro forma business structure is necessary
to implement this study.
It is proposed that an industrial sewage disposal district similar to
local improvement districts normally used to build sewer lines and
pave streets should be formed using the offices of the City Attorney,
City of Kodiak, Alaska.
This district would be composed of the processors, each of whom
would have 1 vote, plus the City Manager of Kodiak who would have
a vote. They would form a board of directors who would contract with
a management firm to arrange the financing, erect the plant and hire
the plant personnel and operate the business.
The City of Kodiak would donate the land necessary for the require-
ments of the plant. With this land the sewage disposal district can
borrow the funds required to finance the plant by morgaging the land
and the plant.
This money could be obtained through the Small Business Administra-
tion, Economic Development Administration, or the Agency of the
State of Alaska empowered to make such loans.
The management firm would make recommendations to the board of
directors regarding the establishment of dumping fees and other
matters concerning the group which would be voted upon by their
board.
This district would be formed immediately so that continuity of effort
is maintained and the time necessary to build a plant capable of
reducing the pollution load to satisfy Federal and State of Alaska laws
is minimized.
71
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SECTION XE
ALTERNATE DISPOSAL METHODS
Handling of the entire industrial waste load by dumping at sea has
been mentioned as an alternate possibility.
An economic analysis shows that it would require ocean-going barges
and tugs. The 12 barges required plus 1 ocean-going tub have been
quoted by experienced towboat operators at $1, 500 per day. With 2
tugs it would be $2, 000 per day.
Based on a 350-day season, the nonrecoverable costs would be
$525, 000 per year and $700,000 per year respectively.
Another possibility, the hauling of the waste to a sanitary landfill,
has been explored.
There are 50, 000 tons per year of wet waste to dispose of.
Trucking costs are $0, 20 per ton mile. The present landfill is
approximately 6 miles from the waterfront. The trucking costs
to haul this waste would be $60, 000 per year, The present 120-acre
landfillj according to the Kodiak Island Borough Comprehensive Plan (1),
states that, "Drainage courses passing through the fill will cause
erosion and drainage problems and increase the likelihood that Monashka
Bay will be contaminated. "
The 50,000 tons of wet proteinaceous waste is approximately 15 times
the present waste load and according to recent studies, will cost $3. 50
per ton or $170, 000 per year to comply with present solid waste manage-
ment standards.
The cost to the processors in providing the necessary dewater de-
vices and holding hoppers is estimated to be at least $25, 000 per
plant or $375, 000.
The total annual direct cost of sanitary landfill disposal would be
approximately $230, 000. This figure does not include any costs by
the processors for dewatering and holding hopper nor does it include
any hauling costs for cover material or treatment of fill leachate.
The third possibility, the welding of a sewer line connecting the
processors' plants to a primary treatment plant, is not a part of this
73
-------
contract. However, in discussions with sanitary engineers, a capital
outlay of at least $3, 000, 000 will be required to treat the 5 million
gals, per day of effluent. This does not include the costs of disposing
of the 50, 000 tons of wet solids captured by the treatment plant.
Considering the above alternate disposal methods it would appear that
the by-product recovery method is clearly the most desirable.
74
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SECTION XIII
IN-HOUSE IMPROVEMENTS AT PROCESSING PLANTS
Since the inception of this project, periodic visits by assigned
engineering personnel have been made to all seafood processors
operating in the City of Kodiak to discuss improvements to their
plants that would make waste collection less costly and more
efficient.
The more efficient plants use flumed water as the carrying agent for
their wastes to a submerged outfall. Others have multiple waste
discharges from various points without a common collection system.
The proposed plan for solid waste collection would necessitate
elimination of multiple outfalls with all wastes being collected for
dewatering and transfer to the barging system. This would facilitate
ultimate connection to an industrial sewer system for the remaining
liquid wastes.
Another area where in-house improvements were suggested is in
economy of water usage. The City of Kodiak does not have an
inexhaustible water supply and shortages have been periodically
encountered. Some plants do not adjust flow of fluming and washing
water with variation of the throughput of materials. During periods
of slack operation water consumption per unit of material processed
can be excessive. Automatic controls on water lines keyed to
instantaneous production rates should be installed where feasible.
Automatic shutoff valves on hoses used for wash down were also
discussed. In some plants flume sizes are not properly scaled to
production rates and arrangements to minimize water needs have
not been given proper consideration. With possible increased
water rates or liquid waste dumping charges on a volume basis,
these factors would be of even greater importance.
75
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SECTION XIV
ACKNOWLEDGMENTS
The assistance of the following persons in furtherance of this project
is gratefully acknowledged:
The Honorable Peter Resoff, Mayor of the City of Kodiak, Alaska.
Mr. Holland Jones, City Manager for the City of Kodiak, Alaska.
Dr. Murray Hayes, Associate ^Regional Director of the National
Marine Fisheries Service of Kodiak.
Dr. Winston M. Laughlin, Research Soil Scientist for the Alaska
Agricultural Experiment Station at Palmer.
Mr. John Spinelli, Research Chemist for the National Marine
Fisheries Service in Seattle, Washington.
Dr. Sidney M. Cantor, Consultant F. A. O. United Nations,
Haverford, Pennsylvania.
Mr. Kenneth A. Dostal, EPA Project Officer, Pacific Northwest
Water Laboratory, Corvallis, Oregon.
Also many of the managers and personnel of processing plants in
Kodiak have made valuable contributions.
77
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SECTION XV
REFERENCES
1. Tryck, Nyman & Hayes, Kodiak Island Borough Comprehensive
Plan 1968 - 1999, Part 2: Kodiak Urban Area Transportation
and Utilities Plan, Anchorage, Alaska (1969)
2. Perkins, C. E. , Private communication.
3. National Marine Fisheries Service, Private communication.
4. National Marine Fisheries Service Contract No. 14-17-0007-960
Progress Report No. 4, October 10, 1968
5. Spinelli, John, Private communication.
6. Block, R. J. , Amino Acid Composition of Proteins and Foods,
Springfield, Illinois (1945)
7. Horn, M. J., Jones, D. B. and Ring el, S. J. , J. Biol Chem,
138:141 (1941)
8. Cuthbertson, W. R. and Philips, H., Biochem. J. , 39:7(1945)
9. Lindleg, H. and Philips, H. , Biochem. J. , 39:17(1945)
10. Blackburn, S. and Lee, G. R. , Biochemica et Biophysica Acta,
19:505 (1956)
11. Schuman, T. E. W. . J. Franklin Institute. 208:405(1929)
12. Furnas, C. C., Trans American Society of Chemical Engineers.
24:192
13. American Public Health Association, Standard Methods for the
Examination of Water and Waste Water, 12th Edition, pp 510-514
New York, New York (1965)
14. U. S. Department of Commerce, Industrial Fishery Products,
Situation and Outlooks (Feb. 1971)
15. Sidney M. Cantor Associates, Inc., Private communication.
16. Laughlin, Winston, Private communication.
79
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SECTION XVI
PUBLICATIONS
1. Johnson, Edwin Lee, and Penis ton, Quintan P., "Pollution
Abatement and By-Product Recovery in the Shellfish Industry, "
Proceedings of the 2nd Symposium on Food Processing Wastes,
Denver, Colorado (March 23-26, 1971)
2. Johnson, Edwin Lee, and Peniston, Quintin P. , "Pollution
Abatement and By-Product Recovery in the Shellfish Industry, "
Proceedings of the 26th Annual Purdue Industrial Waste Conference,
West Lafayette, Indiana (May 4-6, 1971)
81
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SECTION XVII
APPENDIX
Analytical Methods and Investigative Procedures
C. O.D, - "Standard. Methods for the Examination of Water and
Waste water, " 12th edition (1965), page 510, American Public Health
Association, Inc., 1790 Broadway, New York, New York 10019.
B. O. D. - 5 Day - "Standard Methods" loc. cit, , page 415.
Solids - Shellfish Waste - 16 hours drying in air oven at 105° C.
Solids - Fish Wastes, Extracts, etc. - 16 hours, vacuum oven, 60° G.
Fat - Ether extraction on dried sample in Soxhlet apparatus.
Ash - Burn at low temperature in platinum. Complete ignition at
600° C in muffle furnace to constant weight.
Sulfated Ash - Ash as above to complete combustion of carbon, cool,
moisten with sulfuric acid and reheat in muffle to 600° C.
Calcium - Ash as above, dissolve ash in dilute HC1, add ammonium
oxalate solution and slight excess of ammonia. Digest on hot plate
until excess ammonia is dispelled. Cool, filter on asbestos pad in
Gooch crucible. Wash, transfer to beaker, add dilute sulfuric acid,
heat and titrate with standard potassium permanganate solution.
Total nitrogen - Kjeldahl procedure - Sodium sulfate-copper sulfate
catalyst. Biuret Protein Analysis, adaptation of Technicon Auto-
analyzer procedure N-14b for total protein to permit manual colori-
metric tests. Used for protein extraction rate studies. Standardized
for each run against specific protein involved using Kjeldahl procedure.
Chitin in Shellfish Waste - Grind 1 gram dry samples to about 1/8 inch
mesh. Digest in about 100 ml 2% NaOH at 100°C 1 hour. Filter on
medium tared sintered glass crucible. Transfer to beaker and repeat
NaOH extraction. Refilter on same crucible. Retransfer to beaker
and treat 12 hours at room temperature with 100 ml 5% HC1. Refilter
on sintered glass. Wash with hot distilled water until no test for
chloride. Dry at 110°C 16 hours and weigh. Check for ash and nitro-
gen content. Should be less than 1. 0% and 6. 9% respectively.
83
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Protein in Shellfish Waste - Determine total nitrogen. Determine
chitin as above. Subtract chitin nitrogen from total nitrogen and apply
factor. (15% nitrogen in shellfish protein)
Cystine in Shellfish Protein - Protein is hydrolyzed by heating in 6N
HC1 under reflux for 24 hours. Cystine is determined in the hydrolyzate
by Vessel's modification of the Flemming reaction (2).
Protein Extraction Rate Studies - A sample of shellfish waste of desired
particle size and known protein content is suspended in distilled water
contained in a round bottom flask fitted with a reflux condenser, a
mechanical stir re r, a thermometer and a sampling port. The flask
is heated by an electric mantle controlled by a variable transformer.
When the aqueous sample suspension has attained the desired reaction
temperature, a preheated NaOH solution in amount calculated to bring
the sample suspension to the desired alkali concentration is quickly
added and timing is started. Small samples (3 to 5 ml) of the suspen-
sion are withdrawn at noted times. These are immediately filtered
and analyzed for protein by the biuret colorimetric procedure (loc. cit. ).
One or more of the samples are also analyzed by the Kjeldahl procedure
for standardization. Extraction rate constants are calculated as
described in Section VII, page 35 and 37.
Calculation of Waste Composition - Analytical values for solids, fat,
Kjeldahl nitrogen, and sulfated ash or calcium are converted to a
dry basis calculating calcium or sulfated ash to CaCO . The following
equations are then used to obtain percent chitin and percent protein.
% Chitin + % Protein = 100 - %Fat - % CaCO
(0. 069)% Chitin + (0. 150)(% Protein) = % Kjeldahl nitrogen
A nitrogen content of 1 5% for shellfish waste protein is in better
agreement with actual analyses than the usual 16% (Protein = 6. 25 x N).
Calculated chitin values can be compared with actual yields by isolation.
Pilot Plant Extraction Studies - Wastes are held frozen in a nearby
cold storage warehouse. Sufficient waste for a pilot plant run (30 to
90 Ibs) is brought to the laboratory and ground with water using a
restaurant size Hobart garbage grinder. The ground waste is drained
on a 40-mesh stainless screen and transferred to one or more of
four small portable cement mixers.
The mixers are externally heated with gas burners. They are equipped
with screens for draining and thermometers. They can be operated
84
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singly for batch processing or as a four stage countercurrent system.
The charge to the mixers is made up with calculated amounts of water
and 10% NaOH solution to give a desired liquor to solids ratio (usually
6 to 1) and a desired alkali concentration (usually 0. 5 to 1. 0%). The
mixers are rotated and held at the desired temperature (50° C to 80° C)
for the desired reaction time (0. 5 to 2. 0 hours). On completion of the
extraction stage, mixers are tilted to drain through screens clamped
to the face. Samples of the sodium proteinate liquor are analyzed for
protein content (Kjeldahl nitrogen) and for unconsumed NaOH (conducti-
metric titration). The liquor may be processed for protein recovery
by isoelectric precipitation or be advanced to another extraction stage.
Extracted solids are transferred to a Bock laundry reclaimer centrifuge
for further dewatering and washing. Samples are analyzed for solids
and residual protein. Solids may be advanced without washing to another
extraction stage or may be treated for chitin recovery.
85
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Accession !Viim6rr
Sn&jerf Fivlcf A,
05D
SELECTED WATER RESOURCES ABSTRACTS
INPUT TRANSACTION FORM
Organization
Food, Chemical & Research Laboratories, Inc., Seattle, Washington and
Engineering-Science of Alaska, Anchorage, Alaska
Title
Pollution Abatement and By-Product Recovery in Shellfish and Fisheries Processing
10
Authors)
Johnson, Edwin Lee
Peniston, Quintin P.
Braun, F. W. , P. E.
Project Designation
EPA Project #12130 FJQ (Formerly 11060FJQ)
Note
22
Cita f i on
23 I Descriptors (Starred First)
Industrial Wastes*, Waste Treatment*, Water Quality Control*, Pollution
Abatement*, By-Product recovery*
Identifiers (Starred First)
Alaska Fisheries and Shellfish Processing Waste Treatment & By-Product
Recovery* Protein recovery by alkali extraction Economics of Treatment*
27 Abstract , , , . ,
1 Laboratory and pilot plant studies show that utilizable by-products can be obtained
from shellfish wastes produced at Kodiak, Alaska. Alkali extraction of the
contained protein leaves a matrix of chitin and calcium carbonate. The chitin-calcium
carbonate matrix can be converted chemically into its components.
Other fisheries1 wastes found at Kodiak: salmon waste and small fish associated
with shrimp can be liquified by alkali treatment, partially neutralized with acid,
and converted into oil, bone meal and 50% solubles.
The economics and pollution abatement capabilities of the proposed plant are dis-
cussed. The construction and operation of this plant would reduce the yearly
pollution load from the present 22. 1 million Ibs per year of C.O.D. being dumped
into Kodiak Harbor to 6. 6 million Ibs per year of C.O.D.
Preliminary designs are submitted for the implementation of this process,
together with indicated markets and plan of operation.
Abstractor
______Edwin Lee Johnson
Institution
Food. Chemical & Research Laboratories, Inc.
»VRil02 IREV JULY 19691
WR Si c
SEND TO WATER RESOURCES SCIENTIFIC INFORMATION CENTCR
US DEPARTMENT OF THE INTERIOR
WASHINGTON. O. C.
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