Method for treating sewage by using cationic surfactant and electric flocculation

The invention discloses a method for treating sewage by using cationic surfactant and electric flocculation. The method comprises the following steps of (1) dissolving a cationic surfactant into a proper amount of water to obtain a mixed solution; (2) adding the mixed solution into sewage to enable the concentration of the surfactant to be up to 0.05-0.5g/L; and adding sodium chloride, and carrying out electric flocculation reaction under the conditions that the temperature is 20-25 DEG C, the initial pH value is 6.5-7.5, the stirring speed is 200-300r/min, a pure aluminum electrode is adopted, the distance between polar plates is 0.5-2.0cm and the current density is 1.07-8.52A/m . By using the method, the sewage treating efficiency is remarkably improved. Compared with the traditional electric flocculation technology, the method has the advantage that the bubbles of hydrogen generated in the reaction process are smaller, closer and more stable after the cationic surfactant is added, so that the floating effi