Reclaimed water reuse treatment process of coal gas wastewater

The invention discloses a reclaimed water reuse treatment process of coal gas wastewater, and relates to the technical field of environmental protection and sewage treatment. The invention discloses a reclaimed water reuse treatment process of coal gas wastewater, which comprises the following steps: partially removing hardness of gasification wastewater, controlling the hardness to be 500-800mg/L, carrying out improved secondary A/O biochemical treatment on the gasification wastewater, production wastewater and domestic sewage, thoroughly removing hardness of the gasification wastewater, desalted water station discharged water and circulating water discharged water after the gasification wastewater, the production wastewater and the domestic sewage reach an ultra-low discharge water quality standard, and carrying out secondary A/O biochemical treatment on the industrial wastewater and the domestic sewage after the industrial wastewater and the domestic sewage reach the ultra-low discharge water quality stand