Mechanistic and Practical Aspects of Phosphorus Removal from Wastewater Using Iron(III) Salt

摘要

Phosphorus removal was evaluated at several points in a conventional wastewater treatment process. Samples were taken from a secondary plant utilizing a high rate trickling filter on municipal wastewater. Treatment of settled primary effluent, secondary effluent and settled secondary effluent was considered. The experimental matrix included ferric ion dosage and pH level. Sampling points were selected to highlight process variables of interest. These included organic carbon content and unsettled solids content. In all cases, phosphorus removal was substantially less than predicted from pure species solubility data. In addition, the effect of unsettled or unsettleable solids is marked. In all experiments, comparisons of removal efficiency were made for filtered and unfiltered portions of process samples. Beyond the obvious effects of cation dosage and pH, the nature and concentration of particulate matter appear to be important treatment variables.