Full-Scale Manipulation of the Empty Bed Contact Time to Optimize Dissolved Organic Matter Removal by Drinking Water Biofilters

A study was conducted at a water treatment plant to optimize parallel rapid gravity biofilters for dissolved organic matter (DOM) removal. The treat urban and agriculturally impacted river using commercial non-adsorptive, expanded-clay filter medium. aimed locate the optimal operating conditions via experimental manipulation of biofilter empty bed contact time (EBCT) during full-scale operation plant. During two-month experiment, times in four were switched maintained 15, 30, 50, 80 min by manipulating hydraulic loading on each filter. removal efficiency fractions increased with EBCT carbon (DOC) microbial humic-like (F290/420) protein-like (F280/340) fluorescent matter. Other DOM largely unaffected biofiltration, or slightly higher concentrations effluent. Protein-like fluorescence is associated labile fractions, which are known be removed poorly drinking barriers apart from biological filters. results suggest that long (>30 min) have advantages some filters, especially if placed ahead sensitive biofouling, e.g., membranes.