COD ADSORPTION CAPACITY OF THE ACTIVATED-SLUDGE - ITS DETERMINATION AND APPLICATION IN THE ACTIVATED-SLUDGE PROCESS

Proper control of the activated sludge process is essential in ensurin g production of good effluent. COD adsorption capacity (CAC) of the ac tivated sludge could be used as a control parameter. CAC is determined by mixing the activated sludge with the settled sewage and measuring the instantaneous COD reduction per unit mass of activated sludge. CAC measures substrate removal by physical adsorption and reflects the qu ality of the activated sludge. CAC of a healthy activated sludge incre ases with the flow along the aeration units. CAC could be used for pro cess decision on variation in air supply and feed pattern to the aerat ion units. in a modified process to cope with sludge bulking problem C AC could be used to estimate the air supply to the aeration unit which is merely used for reaerating the returned sludge.