PERFORMANCE CHARACTERISTICS OF A
ROTATING BIOLOGICAL CONTACTOR (RBC)
TREATING A CHEESE PROCESSING WASTEWATER
William J. Mikula, Design Engineer
O'Brien & Gere Engineers, Inc.
Poughkeepsie, New York 12601
James H. Reynolds, Associate Professor and Head
Division of Environmental Engineering
E. Joe Middlebrooks, Dean
College of Engineering
Dennis George, Assistant Research Professor
Division of Environmental Engineering
Utah State University
Logan, Utah 84321
INTRODUCTION
General
Wastewater treatment in the dairy food industry is accomplished utilizing various biological treatment methods. Most dairy food plants discharge their wastewaters to municipal sewerage systems, but a small percentage of the industry uses onsite wastewater treatment systems [1]. These onsite wastewater treatment facilities generally yield high carbonaceous substrate removals, but variations in influent characteristics frequently hamper
treatment process performance.
Rotating Biological Contactors (RBC) have become established as competitive, cost-
effective systems for the treatment of biodegradable wastewaters. These units are being
used to treat many different types of wastewaters in a multitude of treatment process
configurations. Applications of the RBC process in the dairy food industry have included
treatment of a synthetic dairy waste [2-4], pilot-scale [5] and full-scale treatment [6] of
dairy food wastewater, and combined municipal-dairy wastewater treatment [7]. But,
although RBCs are being used in many industrial and domestic wastewater treatment
schemes, there is incomplete information on their performance capabilities.
Objectives
The intent of this study was to further investigate the performance characteristics of
an RBC system treating a cheese processing plant wastewater.
The following specific objectives were achieved in this study:
1. Investigation of the treatability of a particular dairy food wastewater using an RBC
wastewater treatment system.
2. Evaluation of overall and stage performance of an RBC system in treating a highly
variable strength waste under field conditions.
3. Evaluation of overall and stage substrate removal in an RBC system under different
hydraulic loading conditions.
Development of a model to simulate substrate removal within each stage, and calibration
of the model using actual system removal data was also accomplished, and is reported elsewhere [8].
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