Adsorptive contactors for removal of soluble manganese during drinking water treatment

Abstract

Water treatment facilities are often challenged to achieve effective soluble manganese (Mn) removal in the face of competing needs to achieve other water treatment objectives (e.g., disinfection by‐product control and biological filtration). Previous research has demonstrated that effective soluble Mn removal can be achieved on media surfaces coated with manganese dioxide [MnOx(s)]. This research study demonstrated that MnOX(s)‐ coated media could be used as a post‐filtration adsorptive contactor to promote effective soluble Mn removal over a wide range of solution pH values (6.3‐8.0), free chlorine levels (1.0 mg/L and greater), initial soluble Mn concentrations (0.03‐0.3 mg/L), and hydraulic loading rates (up to 24 gpm/sq ft). Use of a postfiltration Mn adsorptive contactor in the overall process treatment train would allow water utilities to ensure effective Mn control while achieving other important water quality and regulatory compliance objectives.