China's rivers and rivers are seriously polluted by metal pollution. The national sample survey of rivers and rivers has a river bottom pollution rate of 87%. All major water systems have different degrees of pollution. The river water section also presents different pollution. The pollution is mainly caused by total copper and total cadmium. Caused by heavy metals such as total lead, there are also differences in the excess of different areas. These are mainly the pollution caused by direct discharge of wastewater in the process of rare earth production.

The wastewater generated during the production of rare earths contains a large amount of heavy metals, which can cause pollution of water bodies. The best way to solve this problem is to use polymer PAM flocculation sedimentation method. PAM (PAM) can be divided into acidic wastewater and alkaline wastewater anion and cationic PAM according to ion type. PAM has a long molecular chain, which decomposes into many reactive functional groups after hydrolysis, which can reduce the potential between the ion diffusion layer and the adsorption layer in the solution. The suspended matter and colloid in the adsorption solution form a large floc group, which accelerates the colloid suspension. The sedimentation of matter and heavy metals leaves it with moisture, and the wastewater is treated to become clear and meet emission standards.