Research for flocculation effect of combinedmicrobial flocculation agent

Combined microbial flocculation agent is produced by adopting the cheap bottom material and mixing and fermenting bacterial strain, and its flocculation effect is determined by the experiments. The paper introduces the determination of the optimum dosage of flocculation, the optimum pH spectrum and the dosage of coagulant aidcalcium chloride(CaCl2), based on the fountainhead of Songhua River and strong acidic wastewater. The experiments indicate that the flocculation dosage to be added varies with the water quality. The optimum dosage for the fountainhead of Sonhua River is about 14 mL/L and for the acidic wastewater, the dosage needs to be increased. The optimum pH spectrum is about 7.5.Combined microbial flocculation agent is rendered effective by adding coagulant aid. The optimum flocculation efficiency comes from adding 10 % CaCl2 1.5 mL/L. Meanwhile, the effect of temperature on flocculation efficiency is very little, and settling involves the shortest possible time at 10 ℃, as shown by settling curves.