A Comparison of Coarse vs. Standard Filter Media Configurations – Granular Media Filtration Pilot Study

As part of the South Bayside System Authority Wastewater Treatment Plant (SBSA) Dual Media Filter (DMF) Performance Study, a pilot study was conducted to assess various granular media configurations for the following parameters:Filter runtimes (length of time in between filter backwash procedures)Filter effluent characteristicsA pilot plant was installed at SBSA in November 2003 and used to conduct the abovementioned evaluation. The findings of the study revealed that utilizing granular media configurations (3.4mm – 6.9mm Effective Size (ES)) that are approximately 3-5 times coarser than the existing SBSA granular media configuration (1.4mm ES Anthracite over 0.6mm ES Silica Sand) results in filter runtimes up to 360% longer than the existing media, while generating filter effluent characteristics that meet National Pollutant Discharge Elimination System (NPDES) plant discharge requirements.This work, along with additional research, initiated a plant-scale study to evaluate the findings of the pilot study. The results of the plant-scale study will be available in the winter of 2005.