NOUFERROUS METALLURGICAL EQUIPMENT

Based on the AAO treatment process of a typical urban sewage treatment plant in the north, the phosphorus removal effects of ferrous chloride, ferric chloride and polyaluminum chloride were compared through a pilot test. The results showed that when the coagulant dosage was 30mg/L, the removal rate of total phosphorus (TP) by ferrous chloride was the highest, which could reach about 91%. Based on the results of the pilot test, 30mg/L ferrous chloride was added to the aeration tank at the production site. It was found that after continuously adding ferrous chloride for 58h, TP in effluent was maintained at 0.37-0.44mg/L, and the water quality was stable and up-to-standard. After 68h of stopping dosing, TP in effluent went back to about 2.07mg/L, indicating that ferrous chloride is an effective phosphorus removal agent.