Operation of the Largest High Rate Clarification System for CSO Control in North America

The operational performance data indicates that the DensaDeg system can achieve removal efficiencies of 70 to 95 % for TSS, a removal of 55 to 70 % for the total CBOD and a removal of 70 to 95 % for Total Phosphorus. The wet weather is treated in the four different modes including basin equalization and recombination with secondary effluent while continuing to comply with the current NPDES standards.The design of the facility was based on the results of a full scale pilot test of both the Actiflo and DensaDeg systems. Design criteria were selected that utilized the high surface overflow rates and provided for the proper chemical treatment. The design also included the operational flexibility such that the high rate system can be used in place of the existing primary treatment.The DensaDeg high rate clarification system can function as CSO treatment facilities which produce high quality effluent and operational flexibility.