Polyacrylamide has good flocculation effect and good effect in sludge dewatering, so it has important value in sand washing and sand making industry.

With the continuous development of sand making industry, washing sand by polyacrylamide can achieve the effect of recycling after the wastewater and mud are treated, which not only saves the cost, but also increases the efficiency of sand making.

How can polyacrylamide be used in sand making and sand washing? Firstly, according to the characteristics of water quality, 15% to 30% of sludge is contained in the sewage and mud of sand washing field. This kind of sewage and mud can not be naturally precipitated, so polyacrylamide flocculant needs to be added for flocculation and sedimentation.

The sewage and sludge in the sand washing field pass through several sedimentation tanks, and the sludge is pumped into the sludge tank by the mud pump before adding polyacrylamide. After the coagulation effect of polyacrylamide, the sludge is dewatered. After being treated by the filter press, the filtered water enters the sedimentation tank for recycling. Polyacrylamide is adsorbed in this process. The effect of bridge, sedimentation and net catching can achieve the effect of sludge dewatering. Generally, it is put into use in front of the sedimentation tank and before entering the filter press.

Due to the characteristics of some sediment, polyacrylamide alone can not achieve the best effect, usually need to add inorganic coagulant such as polyaluminum chloride combined with PAM can achieve the best effect of sludge dewatering.