Preliminary  Process
Design and Treatability Studies of Fish
Processing Wastes
F. E. MATUSKY, Partner
J. P. LAWLER, Partner
T. P. QUIRK, Partner
Quirk, Lawler, and Matusky
New York, New York
E. J. GENETELLI, Assistant Professor
Rutgers University
New Brunswick, N. J.
PROCESS DESIGN
Introduction
This paper summarizes a rational approach to process design for a joint plant
for the treatment of wastes from domestic sewage and fish and chip processing.
The major problem was to determine the effect of the proposed processing operations on the joint treatment system. The approach used combined a study of an
existing fish plant and treatability of a synthetic waste.
Determination of Waste Characteristics
Average fish waste characteristics were estimated from the work of Paessler
and Davis (1), and waste samples were collected from a nearby existing fish processing plant. Plant production methods were observed at this plant and compared
to the proposed fish processing layout.
Table I shows a comparison of the existing and proposed operations. The
principal wet operation at the existing plant resulted from water transport of fish
in flumes along a manual filleting line. Fish waste or gurry was also transported
to a fish meal plant via flumes. The proposed plant will also process fish fillets;
however, fish and gurry will be handled by belt and drag conveyors resulting in
considerably less waste water. In part, this advantage is offset by the employment
of a fish washing machine at the conveyor system. It is anticipated that suspended
and dissolved solids pick-up in the wash water would be similar to that of the existing plant flume water. Wastes resulting from equipment and floor washdown
would also be similar. The fish handling differences between the two plants will
be reflected in different waste-water volumes having similar physical and chemical characteristics.
Waste samples were collected from the fillet production line flume, floor
drains, fish-scaling machine, points on the screw-conveyor drain system and at
the discharge of the deodorizer spray and evaporator condensate lines. A sample
of the fish meal plant centrifuge underflow or stickwater was also collected for
analysis. BOD, COD, suspended solids, oxygen transfer coefficient and pH determinations were made.
The results from at least two replicate samples for each test were adjusted
and weighed in accordance with Menhaden processing waste experience. The adjusted waste concentration values were then employed to determine the proposed
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