Preaeration treatment of volatile wastewater components

摘要

A process is described for aerobically treating wastewater containing volatile compounds to degrade the volatile compounds without liberating them to the atmosphere. Influent wastewater and return sludge from an aerobic biophysical wastewater treatment system are contacted in a preaeration zone where a minimum dissolved oxygen concentration of about 1 mg/l is maintained. In this preaeration zone a significant portion of the volatile compounds are biologically degraded. The minimum oxygen concentration in the preaeration zone is attained by prior aeration of the return sludge or by adding a small amount of oxygen to the preaeration zone. The mixture of influent wastewater and biophysical solids depleted of volatile compounds then flows to an aeration zone for further removal of pollutants.