Cation and anion adsorption at the solid/solution interface plays an important role in several chemical fields such as colloid and interface chemistry, soil chemistry and geochemistry,aquatic chemistry, environmental chemistry, catalysis, and chemical engineering. The basic principles of mineral application to engineering are adsorption and precipitation reactions on mineral surface. The treatment of industrial pollutants of heavy metal elements, characterized by low cost and high efficiency, is not only the most important problem in the field of environ- mental protection all over the world, but also one of the important subjects on the water treatment. Having studied the mechanism of interface reaction between solid sulfide and heavy ionic solution, the authors discovered the new method of sulfide→stirring→CaO adjusting pH value to treat the sewage water containing Cr6+,Cr3+,Cu2+,Zn2+,Ni2+,Hg2+,Pb2+,Cd2+in the electroplate factory. It is proved through many experiments that the method has attained the national standards of sewage treatment. This method is very important for environmental protection, and the prospects of its application is very bright.