Abstract:

A novel industrial-scale process combined circulating biological aerated filter (CBAF) and filtration was used to treat the slightly polluted wastewater for reuse in a petroleum refinery.The influences of packing size and height, hydraulic retention time and dissolved oxygen concentration on treatment efficiency for the CBAF process were investigated.The CBAF process can simultaneously carry out carbonation, nitrification and solids filtration in one unit.The wastewater was treated by the CBAF process under optimal conditions: hydraulic retention time of 100 min, dissolved oxygen concentration of about 3 mg·L^-1 and the backwashing cycle of every 2—3 days.The results of the combined process showed that the average removal efficiency of COD, oil pollutants, NH₃-N and SS was 62.6%, 71.7%, 92.6% and 97.0%, respectively.And the average effluent concentration of COD, oil pollutants, NH₃-N and SS was 14.4 mg·L^-1, 0.75 mg·L^-1, 0.49 mg·L^-1 and 2.4 mg·L^-1, respectively.The quality of the effluent can meet the requirements of industrial water reuse.

Key words:

循环生物曝气滤池（CBAF）, 过滤, 炼油厂, 轻度污染废水, 回用

摘要：

采用新型的循环生物曝气滤池（CBAF）和过滤组合工艺对炼油轻度污染废水进行净化回用工业试验。研究了填料粒径和高度、水力停留时间和溶解氧浓度对CBAF工艺处理效果的影响。结果表明CBAF工艺具有碳化作用、硝化作用和过滤作用。CBAF工艺净化该废水适宜的操作条件为：水力停留时间100 min，溶解氧浓度3 mg·L^-1左右，反冲洗周期2～3 d。炼油轻度污染废水经该组合工艺处理后，COD、石油类污染物、NH₃-N和SS平均去除率分别为62.6%、71.7%、92.6%和97.0%，出水COD、石油类污染物、NH₃-N和SS平均质量浓度分别为14.4 mg·L^-1、0.75 mg·L^-1、0.49 mg·L^-1 和2.4 mg·L^-1，经处理后出水水质达到工业回用水要求。

关键词:

循环生物曝气滤池（CBAF）, 过滤, 炼油厂, 轻度污染废水, 回用