Effects of reduced aeration in a biological aerated filter

Aeration is a major part of the operating cost in biological aerated filtration (BAF) systems for wastewater treatment. This study investigated the effect of reducing aeration at the City of Windsor's Lou Romano Water Reclamation Plant to find the lowest possible airflow rate while maintaining a satisfactory ammonia and biological oxygen demand (BOD) in the BAF effluent. Profiles of temperature, dissolved oxygen, pH, BOD, ammonia and nitrate concentration were measured along the height of cell No. 7 at the plant, at different time intervals during filtration, at airflow rates varying from 1300 to 1700 m(3)/h per cell. This study found that the BOD and ammonium removal were satisfactory at the lowest airflow rate.