Windsor Combined Sewer Overflow Treatability Study with Chemical Coagulation

Long column settling and jar tests were undertaken as part of a treatability study of combined sewage at the Lou Romano Water Reclamation Plant (LRWRP) in Windsor, Ontario. Different types of cationic polymers were examined in jar tests, and the appropriate dosage and its relationship with the TSS removal were determined for the polymer coagulation process. Settling column tests were used to develop settling rate distribution curves under both chemically aided and unaided conditions, and to examine the performance of polymer coagulation in improving the settleability of wet-weather sewage during CSO events. The results of the long column settling tests for settling rate distributions show that the characteristics of the wet-weather sewage at the LRWRP during CSO events were similar to those of samples collected at actual overflow sites along the Windsor Riverfront. Settling rate distributions demonstrated that polymer addition to the wet-weather sewage significantly improved the settling characteristics.