Abstract: In this article,the function mechanism of strengthening disinfection of waste-water treatment plant and four kinds of disinfection methods are introduced.By comparative analysis on economy and technology of disinfection methods, disinfection sodium hypochlorite is thought of as the first disinfection method of effluent for the middle-scale or small-scale waste-water treatment plant.

Key words: waste-water treatment； disinfection； equipment； cost；