Coking wastewater is generated during coal dry distillation and chemical product recovery, mainly containing phenol, ammonia and other wastewater. The original wastewater is prone to oxidation and turns dark brown, with an unpleasant odor and poor biochemical properties. At present, biological treatment methods are commonly used for coking wastewater.

2. Inlet water quality situation

The wastewater quality of a coking plant is as follows:

COD＜1200 mg/L BOD＜400 mg/L NH3N＜150mg/L

Phenol 100-250 mg/L sulfide 120 mg/L HCN 15 mg/L

After treatment, it meets the second level standard in the national (GB8978-1996) Comprehensive Wastewater Discharge Standard.

3. Process flow:

Wastewater → regulating tank → inclined tube oil removal tank → air flotation device → intermediate water tank → anaerobic reaction tank → anoxic tank → aerobic tank → radial flow sedimentation tank → reuse or discharge

4. Characteristics:

1. Adopting anaerobic aerobic method can remove NH4+- N from water and ensure that the effluent meets the standard.

2. Programmatic operation and easy management.