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In the process of dye production, such as sulfonation, nitrification, diazotization, reduction, oxidation and acid (salt) precipitation, a large number of pollutants are generated. In the dye production, 90% of inorganic raw materials and 10%~30% of organic raw materials are transferred to water. The concentration of pollutants is high, the composition of wastewater is complex, and the wastewater contains a large amount of organic substances and salts. With the characteristics of high CODCr, deep color, strong acidity and alkalinity, it has been a difficult problem in wastewater treatment and has become one of the key environmental pollution sources.