ObjectiveTo reduce the dosage of coagulants and coagulants in coagulation, thereby reducing the production of coagulation sludge, a microsand loading flocculation experiment was conducted.MethodsBased on the research findings from multiple studies, the effects of coagulant types and concentrations, anionic polyacrylamide (PAM), microsand particle size, microsand dosage, and sedimentation time on Total Phosphorus (TP) removal are systematically analyzed below, along with orthogonal test result evaluating the influence hierarchy of these factors.ResultsUnder the same coagulant concentration, the removal effect of polymeric ferric sulfate (PFS) on TP was due to polymeric aluminum chloride (PAC) and ferric trichloride (FeCl₃); the higher the concentration of PFS, the higher the removal rate of TP. The removal of TP showed a trend of first increasing and then decreasing with the increase of PAM concentration. The smaller the particle size of the added microsand, the higher the removal of TP. When the precipitation time was less than 40 minutes, the removal of TP increased with the increase in precipitation time. When PFS was 40 mg/L, PAM was 1.5 mg/L, the particle size of microsand was 50 μm, the amount of microsand dosage was 4.0 g/L, and the sedimentation time was 40 min, the removal of TP could reach 81.46%, and the TP concentration decreased from 0.5 mg/L to 0.093 mg/L. From the result of orthogonal experiments, the influence of each experimental factor on TP removal from high to low was PFS concentration, microsand dosage, PAM concentration, and sedimentation time. The flocs formed by PFS and PAM as coagulants had smaller particle sizes than the flocs adding micro sands, larger flocs were more conducive to sedimentation and could improve the removal of TP.ConclusionThe study reduces the dosage of coagulant by adding microsand, effectively improves the TP treatment efficiency and reduces the economic cost, which provides a theoretical basis for engineering application.