AWWA JAW39328

The purpose of this work was to determine whether dissolved organic carbon (DOC) could be feasibly removed by diatomaceous earth (DE) precoat filters amended with powdered activated carbon or anionic resin. In the first series of experiments, various precoat configurations of DE size, amendment type and concentration, and precoat weight were evaluated for their initial removals of dissolved organic matter and turbidity from a synthetic raw water source. In the second series of experiments, various body feed compositions were tested for their ability to maintain or improve the turbidity and organic carbon removal achieved by the optimum precoat while head loss through the filter was kept to a minimum. Amending the DE filter with a strong-base anionic resin in the precoat and body feed achieved significant removals of UV absorbance and DOC (>50 percent) with excellent turbidity reduction and acceptable head loss development. Includes 22 references, tables, figures.