重钢焦化废水生化处理系统劣化原因分析及恢复过程研究

Deterioration Reason Analysis and Recovery Process Research of Biochemical Treatment System of Coking Wastewater of Chongqing Steel

分析了重钢新区焦化厂废水生化处理系统劣化、系统处理效率降低、出水指标不达标等问题的原因。针对分析结果,对焦炉操作、进水质量控制、脱硫废液外排量及指标控制等进行了优化,并采取措施对预曝气池、好氧池、兼氧池菌种进行了恢复,实现了系统的稳定运行。生化处理后二沉池出水COD质量浓度≤350 mg/L,氨氮质量浓度≤15 mg/L,经絮凝反应后,出水可达《炼焦化学工业污染物排放标准》(GB 16171—2012)间接排放标准。

The reasons of such problems as deteriorated biochemical treatment system of coking wastewater,low system treatment efficiency,and effluent parameters unable to meet standard in Chongqing Steel were analyzed. Based on the analysis results,optimization was made for coking oven operation,inlet water quality control,and control of desulfurization wastewater discharge volume and indicators. Measures were taken to recover the strain of pre-aeration tank,aerobic tank and facultative tank,to achieve the stable operation of the system. In the effluent from secondary sedimentation tank after the biochemical treatment,COD_（cr）≤350 mg/L and NH_3-N≤15 mg/L. After flocculation,the effluent quality met the indirect discharge criteria specified in the Emission Standard of Pollutants for Coking Chemical Industry（GB 16171—2012）.