Dye/pigment wastewater contains a series of organic substances such as halides, nitro compounds, amino compounds, aniline, phenols, and other inorganic salts such as sodium chloride, sodium sulfate, sulfide etc. The pollutant concentration and COD is high, the composition is complex,  and most contain chromogenic groups. The dye/pigment wastewater is dark, high in chromaticity, strong in acidity and alkalinity with high salt concentration.

Direct evaporation and desalting of high-salt wastewater of the traditional technologies will cause the problems of low evaporation efficiency with high cost. The evaporated salts contain a large amount of organic matters with dark color, and is generally classified as hazardous waste with high thoroughly disposal cost.  The series of LONGANTAI catalytic oxidation processes can be used for advanced treatment of high-concentration and high-salt wastewater, to remove chroma and reduce COD. After treatment, the evaporated water is colorless, highly pure and can be directly reused. The steamed salt is white with high purity.