Performance Evaluation of the Existing Three-Lagoon Wastewater Treatment Plant at Pawnee,Illinois.

摘要

This report presents data gathered over a one-year period of monitoring the lagoon system at Pawnee,Illinois,and compares treatment plant performance to design loading rates and the Federal secondary treatment standards. The treatment plant performed very well. Removals of BOD5and fecal coliforms were excellent. During the early part of the year,lagoon effluent passed through a sand filter which was ineffective and contributed suspended solids to the effluent;the filters were later bypassed and suspended solids removal was satisfactory from then on. Fecal coliform removal was satisfactory except for a brief period when chlorine addition was insufficient. In addition to the above parameters,many others were monitored and are presented both in summary form and in complete listings of all data collected during the study. The lagoons performed satisfactorily during the winter months,and anaerobic conditions did not develop despite a thick ice layer.