臭氧/生物活性炭工艺深度处理焦化废水中试

Pilot Test on Advanced Treatment of Coking Wastewater by O_3/BAC Process

以经常规生化工艺处理后的焦化废水为研究对象,通过中试考察了臭氧/生物活性炭工艺深度处理焦化废水的效果和可行性。通过测定生化呼吸曲线及相对耗氧速率来判定焦化废水可生化性的提高程度及活性炭生物膜的成熟情况。结果表明,该工艺用于焦化废水的深度处理是完全可行的。在臭氧投加量为15 mg/L的条件下,可显著提高焦化废水的可生化性,臭氧氧化对COD的平均去除率为10.13%。采用自然挂膜方法培养生物膜,生物膜的成熟时间为25 d左右。在生物活性炭稳定运行后,其对COD和氨氮的平均去除率分别可达28.75%和43.80%,出水COD和氨氮的平均值分别为87.50和7.6 mg/L,均达到了《污水综合排放标准》(GB 8978—1996)中的一级标准。

Taking the coking wastewater treated by conventional biochemical process as the research object, the feasibility and effect of the advanced treatment of coking wastewater by O3/BAC process were investigated in a pilot-scale test. The improvement level of coking wastewater biodegradability and the biofilm growth of GAC were judged through determination of biochemical respiration curve and relative oxygen consumption rate. The results show the process is feasible in advanced treatment of coking wastewater. At the ozone dosage of 15 rag/L, ozonation can improve biodegradability of coking wastewater significantly, and the average removal rate of COD can achieve 10.13%. The biofilm is cultured by natural biofilm formation method. The maturation time of biofilm is about 25 days. After the stable operation of BAC, the average removal rates of COD and ammonia nitrogen are 28.75% and 43.80% respectively. The average concentrations of COD and ammonia nitrogen in the effluent are 87.50 mg/L and 7.6 mg/L respectively, meeting the first class criteria specified in the Integrated Wastewater Discharge Standard （ GB 8978 - 1996）.