Printing and dyeing wastewater is a kind of industrial wastewater with great harm to the environment. It has a large discharge, high chroma and difficult degradation of organic matter, which brings great difficulties to wastewater treatment. It is difficult to reach the standard by using conventional treatment methods. Therefore, it is necessary to find a simple and cheap effective method for decolorization of printing and dyeing wastewater magnesium salt method. The decolorization principle of magnesium salt method is magnesium salt, that is, magnesium sulfate, which is hydrolyzed by alkali to form magnesium hydroxide precipitation with positive charge. It strongly adsorbs anionic dye with negative charge and decolorizes dye wastewater. The treatment of acid dye wastewater with magnesium sulfate has a good effect and a high chroma after treatment. Magnesium salt method can effectively remove water-soluble acid dyes, and the decolorization rate is very high under suitable conditions. In conclusion, the treatment of printing and dyeing wastewater with magnesium sulfate can save cost and reduce secondary pollution to a certain extent. This method is worth popularizing, and it will not pollute water and is harmless to human body.
