CASE HISTORY OF NITRIFICATION OF A RENDERING-MEAT
PACKING WASTEWATER
Tom Green, Project Engineer
Gerry Shell, President
Gerry Shell Environmental Engineer s, Inc.
Brentwood, Tennessee 37027
George Witmayer, Wastewater Supervisor
Moyer Packing Company
Souderton, Pennsylvania 18964
Over the past three years Moyer Packing Company (MOPAC) has made a very substantial investment to improve wastewater treatment at its facdities near Souderton, Pennsylvania. Such an investment had been necessitated by MOPAC's desire to expand production at its plants, whde over the same period of time the requirements of its NPDES
permit have become increasingly stringent, particularly with respect to ammonia removal.
Three years ago the separate treatment facdities at A. F. Moyer and Sons beef packing
plant and North Penn Hide Company rendering plant were both severely overloaded, and
thus unable to comply with discharge requirements. To remedy this situation it was decided to expand facilities at NPH to provide combined secondary treatment for the wastewaters from both plants. Existing facdities were to be modified and used for primary treatment at each plant, and a one-mde-long sewer line and a pump station were to be
constructed to convey wastewater from the beef packing plant to the expanded treatment
facdity at the rendering plant.
A single-stage activated sludge system was designed for a future flow rate of 500,000
gallons per day. It was felt that such a system would provide the necessary removals of
organic and ammonia pollutants and, in conjunction with better-operated existing equipment, would allow all parameters of the discharge permit to be satisfied. As a further safeguard for ammonia removal, a breakpoint chlorination system was designed and installed.
Reported here is a brief case history of wastewater treatment at these plants. Data recorded over the last three years are presented to demonstrate that with proper operation
the modified and expanded facdities are indeed capable of providing the required degree
of treatment.
WASTEWATER SOURCES
Wastewaters which flow to the North Penn Hide Company Wastewater Treatment Plant
originate chiefly from two sources-A.F. Moyer and Sons beef packing plant and North Penn
Hide Company rendering plant. The packing plant wastewater, containing large amounts
of blood, comes from wash-up of the slaughtering floor and various meat cleaning devices.
As may be seen in Table I, high concentrations of BOD and suspended solids are
characteristics of this wastewater.
The Elroy, Pennsylvania, plant of North Penn Hide Company is a large rendering
operation, having two continuous rendering systems, batch cookers and a centrifuge for
blood processing. Six raw materials-poultry waste (offal), beef (bones, fat, etc.), beef
and poultry blood, bakery waste, feathers, and kitchen grease-are processed into various
meals used in animal feed manufacturing and into fats and tallow which, among other
things, are used in manufacturing of soaps and cosmetics. Wastewaters from these operations
contribute high concentrations of BOD, suspended solids, ammonia, and od and grease to
the treatment plant (see Table I).
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