Design and application of environmental protection equipment Water supply and drainage Treatment process
From a technical point of view, printing and dyeing wastewater is a very complex category of wastewater. One of its characteristics is that the components of pollutants are very different, and it is difficult to classify them. The second characteristic is that the main pollution index COD is high, and the ratio of BOD to COD is generally about 0.25, which is poor in biodegradability. The third feature is high chromaticity, and the size and weight of the color developing molecular ion particles in the mixed water are different, so it is difficult to decolorize. There are eight main types of wastewater discharged from each printing and dyeing process, and their water quality characteristics are quite different. In addition, the water quality and quantity fluctuate greatly.