Wastewater Characterization of Fish Processing Plant Effluents

wash water, mixed with guts and blood, drains out at the bottom of the gutting machines.
The fish are inspected after the gutting process and are further manually cleaned if necessary.
During this cleaning step, workers scrape and cut off remaining entrails and fins. Typically,
each manual cleaning station is equipped with a small, constantly running, water hose to rinse
off any offal and/or blood.
2.4 Salmon Canning
The salmon butchered, as described in Section 2.3, is fed into cutting machines which cut the
fish into sections of appropriate size for the cans to be used in the canning machines. Canning
machines then press the salmon sections into cans which are subsequently inspected by workers
who rearrange the material in the cans for aesthetic reasons and add additional material to
under-weight cans if necessary (patching). Lids are then lightly clinched onto the cans, and the
cans are sealed in seamers which operate under vacuum.
Following the sealing, the cans are washed and placed in busses (slatted metal buggies with
movable bottoms) and pressure cooked in large retorts. After the cooking process the cans are
cooled with water which must be chlorinated to a concentration of at least 2 mg/L for a minimum
of 20 minutes to ensure disinfection.
2.5 Salmon Roe Processing
The roe collected during the fish dressing (butchering for freezing or canning) is further
processed by washing and curing in a concentrated brine solution for 20 minutes. Washing and
curing takes place in agitated, circular tubs. The brine is replaced after each five batches of
roe processed.
FREMP 03/21/1994
Fish Processing Plant Effluent 13