Biological filtration for BOM and particle removal from drinking water supplies

Abstract

In this study, biological filtration was operated as a pretreatment of drinking water supplies. Total organic carbon level was monitored to show that biological filtration can remove natural organic matter. The effect of empty bed contact time on the removal of organic matter, color, turbidity and chlorophyll-a was investigated in two down-flow biofilters containing ceramic media. The empty bed contact time ranged from 2 hours to 6 hours. TOC removal was about 40% when EBCT was 4 and 6 hours. When EBCT was reduced to 2 hours, TOC removal reduced to 25%. After biological filtration, 90% of color was removed even though EBCT was reduced to 2 hours. Turbidity of raw water was varied from 5.5 NTU to 15.2 NTU. The effluent turbidity was maintained at less than 0.5 NTU