Such as the choice of two kinds of flocculant and their advantages and disadvantages are present and performance of the strong and complementary, flocculation, coagulant phosphorus waste water treatment of the two main species of phosphorus removal Phosphorus removal of part of phosphorus phosphorus Chemical reaction Precipitate to remove waste water Phosphorus waste water Purification efficiency Polyferric sulfate Dephosphorization Phosphate removal phase Ferric chloride Ferric sulfate Use of polymeric ferric sulfate Phosphorus more economical and polymeric Ferric sulphate New high quality high flocculant coagulation Good quality and fast settling rate Dephosphorization not only reduces the total content of phosphorus in wastewater but also reduces the input of foreign phosphorus and phosphorus in the same process. Phosphorus sulphate Polychlorinated sulphate contains chlorine, aluminum and heavy metal ions and other harmful substances, Machine flocculant, has been put into production use, in particular, the adsorption capacity of colloidal material than the high bridge to send, save the hydrolysis stability, drug dosage; use, stability; dosing amount, , The kind of set oxidation, adsorption, deodorant and other body water treatment agent, with the second pollution of its toxic side effects In this paper, the use of potassium ferrate strong oxidation function, exhibition using potassium ferrate combined with ferric sulfate Potassium potassium as a new species of water treatment agent, the use of single polymerization of ferric sulfate phosphorus, water treatment costs are too high Machine advantage mainly reflects the traditional metal salt flocculant than the machine High price, low price, wide range of strategies, phase High quality and granularity, the total adsorption and bridging ability, handling difficulties and high volume, flocculation effect, bridge colloidal material adsorption capacity, so that the water phosphorus content of urban sewage discharge standards compared to high polymer , The use of the drug dose comparison and did not expect effective, bactericidal, bleaching, narrow drug dosage range, the United Poly Ferric sulfate in addition to sewage phosphorus, machine high although the source of raw materials to produce more sludge, to encourage the same complex machine flocculant, Overcome their shortcomings