Treatment of Waste Water from Smelters with High As and Cd Contents
For the waste water from smelters with high contents of As and Cd ions,the treatment procedure is firstly to add lime milk to allow the free acid in the waste water to form gypsum,then conduct neutralization treatment with lime and add ferrous sulphate to remove metallic ions of Cu,Zn and As in the water,at last remove Cd with the method of cadmium phosphate precipitation to make the metallic ion content in the final effluent meet the national discharge standard,and the waste water after treatment can be recycled.