The effects of magnetic seed, aluminum sulphate and pH value on phosphorus adsorption, precipitation and coagulation were surveyed. The results made it clear that Al ( III) ion as precipitant and coagulant was the main effect factor on P removal; 研究了磁种、硫酸铝、pH值等对磷的吸附、沉淀、凝聚的影响,结果表明:铝(Ⅲ)离子的沉淀作用是除磷的主要原因;