Microbial environmental treatment of coal chemical wastewater

1. Water vapor formed by combining water precipitated when coking coal moisture and coal material are pyrolysed, and condensed water formed by primary condenser;

2. Washing wastewater produced in the process of gas purification;

3. Water vapor produced in the process of recovering tar, primary benzene and other by-products, among which ammonia nitrogen containing wastewater produced in the process of nitrogen evaporation is the main pollution source.

The characteristics of coal chemical wastewater

1, the water quality is complex, contains a large number of solid suspended particles, high concentration;

2, great harm, poor biochemistry.

Waste water treatment methods

Biological method is the main method of coal chemical wastewater treatment, its treatment process can be summarized as the following three processes: pretreatment, biochemical treatment, advanced treatment.

Pretreatment: mainly includes oil removal, dephenolization, nitrogen evaporation, removal of SS(initial sedimentation tank, coagulation sedimentation tank) and toxic, harmful or difficult to degrade organic matter (desulfurization, cyanide-breaking, advanced oxidation pretreatment).

Biochemical treatment: Biochemical treatment mainly includes A/O, A²/O, SBR, UASB or some new processes.  In each process, the reactor design parameters and bacteria species have a great influence on the treatment effect.

Advanced treatment: after biological treatment, there is still a part of organic matter in the wastewater that can not be degraded by organisms, which makes it difficult for the effluent COD or chroma to reach the standard, so subsequent treatment must be carried out.  Generally have coagulation, adsorption, advanced oxidation, membrane technology.