The magnitude and effects of biological activity in expanded carbon beds used for direct clarification/adsorption treatment of wastewater were investigated. Major aspects of the project involved comparisons of the relative effectiveness of aerobic and anaerobic conditions in the expanded-bed systems, and a comparison of the relative treatment effectiveness of expanded carbon beds of high and low sorptive activity under aerobic operating conditions. The use of short polishing columns to remove traces or organics escaping from on-line adsorbers was also evaluated.

Flushing of a lake means reducing the pollution by clean inflow with an equivalent outflow of polluted water, a process by which clean water both displaces and mixes with the polluted water. Parameters influencing the effectiveness of the cleansing stream, most important and manageable under laboratory conditions, were investigated. Parameters studied were: inlet velocity, inlet width, depth, and basin shape. Testing was conducted on two depths, two inlet widths, three inlet velocities, and four elliptical basins. Primary purpose of the project was to evaluate the various parameters to determine their influences on flushing efficiency, and develop prediction equations based on geometric and flow characteristics of the systems tested. Analysis were completed to develop a test program, analyze the system for comparison with experimental results, and develop prediction equations which incorporate analytical and experimental results of the study.