Printing and dyeing wastewater treatment – application of ozone technology

The dyeing wastewater produced by the textile mill is very polluting to the environment. Therefore, the wastewater needs to be treated before it can be discharged or recycled. Ozone is an extremely strong oxidant and plays an important role in the treatment of wastewater.

Printing and dyeing wastewater is an industrial wastewater with large chroma, high organic content and complex composition. The water also contains a large amount of residual dyes, alkalis, diazo, azo, etc., which is difficult to handle. Textile wastewater is usually treated in three stages:

First: physical treatment, separated by sedimentation and grid filtration;

Second: chemical treatment, adding chemical agents to improve water quality;

Third: advanced treatment, using ozone oxidation technology, effectively reducing COD, BOD values, and greatly improving the reuse of water reuse or compliance.

Ozone application mechanism:

Ozone is a strong oxidant, and its redox capacity in water is second only to fluorine. It is commonly used in the pretreatment and advanced treatment of industrial wastewater. It has many functions in water treatment, sterilization, decolorization, deodorization, deodorization and oxidative decomposition. Ozone is mainly used to discolor and degrade organic matter and reduce COD and BOD values ​​in the treatment of printing and dyeing wastewater.

In dealing with the chromaticity of printing and dyeing wastewater, ozone oxidation can break the divalent bond of the dye-donating or chromogenic gene of the dye, and at the same time destroy the cyclic compound constituting the chromophore group, thereby decolorizing the wastewater.

Ozone reacts with hard-to-degrade organic matter, which changes the toxicity of pollutants and biochemically degrades. At the same time, reduce COD and BOD, further improving water quality. Ozone can oxidize most organic matter and microorganisms in wastewater, and reduce its COD and BOD values without secondary pollution and easy decomposition. At the same time, it can also decolorize, sterilize and deodorize. It has been widely used in the advanced treatment of wastewater treatment.

Post time: Aug-12-2019