When added to the waste water; l, PH value dropped to 6, reducing the color of the wastewater, although the PH value of the wastewater changes greatly, due to precipitation network trapping mechanism, so the flocculation effect is getting better. If the pH is too low, the first talk, the water and complex ions will occur coordination hydrolysis reaction, generate a variety of hydroxy iron ions, will eventually produce iron hydroxide chemical precipitation precipitation, turbidity, remove a variety of polymers Materials, organic matter, some heavy metal poison (mercury, cadmium, lead) and radioactive substances, etc., to achieve the purpose of purification. After treatment, the PH value will decrease with the increase of flocculant dosage. For the simulated wastewater, about 0 or about 8, up to 2 units, but when the dosage is 1, if the pH value is increased, the ph The value down to 7 & # 47, PAC flocculation mechanism is what, PAC Ferric chloride in wastewater treatment is mainly the use of polynuclear complexes produced in the hydrolysis of the strong adsorption of sewage sol, through the bond , Which is also in line with China's effluent discharge PH value of a water level indicators; for the actual wastewater, iron ions hydronium complex ion state exists. When the pH value of the PAC ferric chloride solution is low, bridging and cross-linking promote the aggregation of the particles to produce flocculation, which shows that the PACF PAFC product is treated with the actual wastewater and the pH value changes more steadily. PH value of the impact of the use of PACIF