Abstract: The coal chemical industry sludge is solid waste which produced in the process of coal chemical industry wastewater treatment. On the basis of analyzing the basic characteristics of coal chemical industry sludge, the effects of coal chemical industry sludge reduction with ultraviolet irradiation was carried out. The experimental results showed that after 0 min,10 min,30 min,60 min after UV irradiation, the concentration of TN, TP in coal chemical excess sludge increased because of cell rupture. And due to available to other microorganisms, the concentration of COD showed a trend of increase after decreases first. And the concentration of SS gradually reduced after UV irradiation. So, it can obtain certain coal chemical industry excess sludge reduction using ultraviolet radiation. To provide reference for Ningdong coal chemical excess sludge reduction, it need to further strengthen the experimental and applied basic research on the sludge reduction.

Key words: ultraviolet radiation, coal chemical excess sludge, reduction