Unit Process Performance Modeling and
Economics for Cannery Waste Treatmenl
DENNY S. PARKER, Assistant Engineer
JOHN R. MONSER, Associate Engineer
Water Resources Engineers, Inc.
Walnut Creek, California
ROBERT G. SPICHER, Associate Professor
Civil Engineering Department
San Jose State College
San Jose, California
INTRODUCTION
The canning industry is more frequently undertaking waste treatment operations at the cannery site rather than alternative disposal of its wastes. This trend
is caused by both economic and political considerations and the particular circumstances of each cannery. For instance, canneries presently disposing of
wastes into municipal systems may be faced with increasing municipal assessments or stricter effluent standards. More stringent legislation has necessitated
treatment where treatment was not previously required. Whatever the cause necessitating in-plant treatment, the individual cannery will undoubtedly seek the
least costly answer to its particular waste problem. With this goal in mind, the
purpose of this presentation is to indicate the general format for the technical and
economic analysis of the processes available to the cannery for the handling of
its wastes. To further this aim, several unit processes will be analyzed with reference to one particular cannery waste. Due to the specific nature of this data,
the performance and cost date developed will be rather limited in application and
the reader should keep this in mind in attempting to adapt them to a particular
situation. The application of this data into a general model for the determination of the "best" solution from among the various alternative processes has been
presented (1).
The optimal design of a cannery waste treatment system requires knowledge
of system costs and responses to changes in operation and waste characteristics,
devaluating these system responses and costs, a primary requisite is knowledge of
individual unit process cost and responses to these changes. Figures 1 and 2 summarize the 16 processes considered during the cannery waste research project
(2, 3) for solid and liquid waste handling by putting them into perspective with
regard to the degree of treatment provided. Of these processes, only six will be
reported herein due to time and space limitations.
While technological considerations would eliminate certain system configurations and modify others, a number of alternatives would remain which would
all be technologically possible. The questions then arise, what is the "best"
configuration for in-plant treatment, and what measure of treatment should be
provided in the plant?
The degree of treatment accomplished at the cannery may be partial or
complete, as determined by economic or legal considerations. In some cases the
cannery may find it cheaper to treat part of its wastes prior to discharge to the
municipal system to reduce the "sewer service charge, " or to treat part or all of
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