TREATMENT OF DYEING WASTEWATER USING COAL FLY ASH AS CO-COAGULANT

摘要

This article deals with the co-coagulation of dyeing wastewater by coal fly ash using FeSO_4 as coagulant, Benzo Scarlet 4BS and Brilliant Acid Scarlet 3R as the testing dyes. The optimal concentration of FeSO_4 for co-coagulation process is 0.6-0.8 g/L wastewater, and the concentration of fly ash 4-5g/L. The experimental results show that the co-coagulation process by fly ash helps to improve the color reduction, greatly accelerate the formation and settling of the floe, and reduce the content of the floe. The mechanism for co-coagulation process is discussed and similar effect is obtained when the co-coagulation method is applied for the treatment of the real dyeing wastewater samples.