Analysis and selection of powdered zeolite dosing point in enhanced coagulation–sedimentation for treating micro ammonia polluted raw water

Abstract

AbstractAmmonia pollution occurs frequently in urban water supply systems. Zeolite is a kind of promising adsorbent for ammonium removal. In an actual running water work, different zeolite dosing points should have various influences on the effluent, which, however, draws insufficient attention. This paper focuses on the analysis and selection of powdered zeolite (PZ) dosing point in enhanced coagulation–sedimentation for treating micro ammonia polluted raw water. We investigate the variations of effluent ammonium concentration, turbidity, CODMn and UV254 of the coagulation–sedimentation schemes which have different PZ dosing points and we also analyse the relevant causes. PZ dosing can induce extra turbidity and the existing turbidity can inhibit ammonium removal to certain extent. In CODMn and UV254 removal process, both synergistic effect and antagonistic effect exist, and PZ dosing point determines which effect it is. PZ dosing has a significant synergistic effect on promoting poly aluminium chloride ...