EVALUATION OF A NEW BIOLOGICAL TOWER PACKING
Don F. Kincannon, Professor
A. F. Gaudy, Jr., Professor
School of Civil Engineering
Oklahoma State University
Stillwater, Oklahoma 74074
Gary Utter, General Manager
Air-X-Systems Division
Tulsa, Oklahoma 74106
INTRODUCTION
During the early 1900's the most prominent wastewater treatment process was trickling filtration. The popularity of the trickling filter continued until just a few years
ago. As effluent requirements became more stringent it was found that the rock trickling filter wastewater treatment plant had difficulty meeting these effluent standards.
Thus, the activated sludge process has become the most prominent wastewater treatment
process today.
During the past few years energy consumption has become a national concern, and
may have an important impact on wastewater treatment in the future. When the activated sludge process is compared to the trickling filter (biological tower) treatment
process, in regards to energy consumption, it is found that there is a significant difference in the energy consumption between the two processes. If only the biological part
of the plant is compared, it is found that the activated sludge process will use approximately five times the energy that a three stage biological tower plant will utilize. Dollar
wise this may not be too significant when the energy cost is 3^ per kilowatt-hour. However, at  \04 per kilowatt-hour the dollar difference becomes very substantial.
Due to energy considerations and other factors, there is renewed interest in trickling
filters. However, it is apparent that rock trickling filters will not be satisfactory. Therefore, during recent years high rate treatment of domestic sewage and biodegradable
industrial wastewaters has been accomplished on biological towers packed with scientifically designed plastic media, which has become recognized as an effective and efficient
alternative to conventional methods of biological treatment. In the activated sludge
process many operational changes or slight modifications of the process can be incorporated to increase treatment efficiency. A point in case is the use of pure oxygen instead
of air. However, in the trickling filter or biological tower treatment process it becomes
apparent that the only way to improve the treatment efficiency of the tower is to
either add more of the medium or to improve upon the existing media.
Air-X-Systems have been utilizing a particular medium configuration in their cooling
towers for several years now with very successful results. It seemed logical that it might
also be successful as a biological tower packing. Thus, an experimental program was
developed to evaluate its potential.
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