Wastewater Characterization of Fish Processing Plant Effluents

3 REVIEW OF TYPICAL WASTE MANAGEMENT PRACTICES
3.1 General
As the waste management practices observed in the fish processing facilities visited were very
similar (depending on the throughput of the facility), they are described in detail in the
following sub-sections. Detailed information specific to each facility is presented in Section
4. The sub-sections also include a discussion of the principles of the waste management
practices encountered and their advantages and disadvantages. The description of the practices
are divided in offal transport methods, and screening, which is the typical form of treatment
encountered at the facilities reviewed.
3.2 Offal Transport
A flow diagram of a typical waste treatment scenario is shown in Figure 4. Generally, fish
processing facilities make use of water not only for fish cleaning, but also to flush offal and
blood from equipment and floors, and to transport or flume the offal to floor drains and
collections sumps. Automated processing equipment generally have permanently installed water
sprays to keep the equipment clean and to flush offal away. Typically, large chunks of offal
(heads, tails, fins, etc.) fall into chutes which direct the offal to flumes, or are washed into
flumes, which transport the offal to a collection sump. However, a certain amount of offal
generally falls onto the floor where it accumulates and must be removed manually. This is
typically done by hosing the offal into a nearby drain or flume.
Apart from resulting in high water consumption, this method of equipment cleaning and offal
transport causes the mixing of the rinse water with offal and blood, which has two main
disadvantages:
FREMP 03/21/1994
Fish Processing Plant Effluent 17