66    FEASIBILITY OF PACKED-BED ANAEROBIC
TREATMENT OF POULTRY PROCESSING
WASTEWATER
Stephen R. Harper, Research Engineer
G. Edd Valentine, Research Scientist
Charles C. Ross, Research Engineer
Georgia Tech Research Institute
Environmental, Health & Safety Division
Engineering Technology Branch
Atlanta, Georgia 30332
INTRODUCTION
Almost 15% of the chicken consumed in the United States is produced in the State of Georgia
(Table I). Nearly 700 million birds are processed in Georgia yearly, resulting in approximately 20
MGD of wastewater which requires treatment. Most of Georgia's poultry processors depend on
dissolved air flotation (DAF) for primary or pretreatment of their wastewaters, followed by either
discharge to a publicly-owned treatment works (POTW) or additional on-site biological treatment
such as activated sludge or aerated lagoon as required for direct discharge or land treatment.
DAF treatment is typically successful in meeting pretreatment objectives (i.e., to below POTW
surcharge levels). However, the process is operationally intensive with large daily chemical requirements, and large quantities of sludge are produced as a byproduct. DAF sludges (skimmings) from
many plants are currently transported to rendering facilities where they are processed with other
inedible poultry parts (offal) into animal feed products. Processing DAF sludges is a problem for the
rendering plants, since the sludge has a much higher water content than offal, resulting in additional
expenses for transporting and processing. Moreover, the sludge goes rancid if stored more than one
day, yielding an inferior rendered product. To help alleviate these costs and concerns, a number of
poultry processors are investigating and installing expensive sludge dewatering facilities.
High rate anaerobic treatment systems have been demonstrated to be successful in treating a variety
of food-type wastes and were considered a logical alternative for handling poultry processing wastewater.2 The objective of this study was to determine whether the anaerobic process could be used to
successfully meet or exceed POTW surcharge limits, without producing trouble-some quantities of
sludge. Moreover, initial estimates indicated that daily operating costs could be much lower for
anaerobic treatment than for DAF treatment. Despite the relatively dilute organic waste stream which
Table I.    Comparison of Poultry Production in the United States and Georgia!
Georgia Poultry Production (1985) In Millions
Total Bird Production 694
Pounds of Processed Chicken 2938
Revenue Produced (Dollars) 813
Wastewater Produced (Gallons) 4858
or 19 MGD3
United States Poultry Production (1985)
Total Bird Production 4478
Pounds of Processed Chicken 18851
Revenue Produced (Dollars) 5680
Wastewater Produced (Gallons) 31346
or 120 MGD»
aBased on 250 operating days/year.
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