Foreword:

China is a country with more coal and less oil. With the development of national economy, the demand for energy is increasing. Therefore, coal chemical industry has been developed greatly in areas with rich coal storage. But the coal chemical industry consumes a lot of water and wastewater discharge, so it needs a lot of water resources.

The production process of coal chemical industry is complicated, and the water consumption is huge. Each link will produce a variety of pollutants. Although most of them can be recycled, most of the remaining waste water is toxic and harmful and difficult to degrade pollutants. At present, China's per capita water resources is only 2300m3, large-scale development of coal chemical industry water consumption is as high as 20 ~ 30 million m3, tons of product water consumption in more than 10 tons, therefore, the production of coal chemical wastewater is also very large.