The printing and dyeing industry is one of the industries with high water consumption and high pollution, and the wastewater generated in the production process contains a large number of pollutants such as dyes, additives, acids and alkalis. It is difficult to achieve zero discharge of wastewater with traditional printing and dyeing wastewater treatment methods, which poses a serious threat to the environment and ecology. In order to solve this problem, the technology of zero discharge of printing and dyeing wastewater came into being.
The core of the zero discharge technology of printing and dyeing wastewater lies in the comprehensive treatment and treatment of pollutants in wastewater. The technique mainly consists of the following steps:
Pretreatment: Remove large particles of impurities and suspended solids in the wastewater to provide relatively clear wastewater for subsequent treatment.
Dyeing wastewater treatment: through chemical or physical methods, remove dyes and additives in wastewater, so that the concentration of pollutants in wastewater is reduced.
Acid-base neutralization: By adding acid or alkali, the pH in the wastewater is adjusted to neutral to reduce the interference to the subsequent treatment.
Advanced treatment: Advanced oxidation, membrane separation and other methods are used to further remove trace pollutants in the wastewater, so that the effluent meets the reuse standard.
Reuse: The treated water can be used for cooling, cleaning and other purposes in the factory to realize the resource utilization of wastewater.