METHOD OF TREATING WASTEWATER

摘要

PURPOSE: A wastewater treatment method is provided, which can remove organic matter in wastewater effectively by the effects of high coagulating effect of iron salt and co-precipitation effect of aluminum salt by using mixed coagulating agent of iron salt and aluminum salt. The method can also remove colors effectively so that the resulting water can be used as reuse and eliminates the necessity of chlorine injection to sterilize by excellent sterilizing effect of electron beam irradiated to the water. CONSTITUTION: The method comprises the following steps: (i) irradiate electron beam to the wastewater passed the last settling tank of activated sludge tank by 1-3 kGy of energy absorbing amount; (ii) feed coagulating agent mixture of ferrous sulfate and aluminum sulfate by a ratio of substantially 1:1 to give a concentration of 300-1000 ppm and agitate for coagulating organic matter; and (iii) settle and remove the coagulated matter by feeding polymer coagulating agent by 1.5-3 ppm.