针对城市污水处理厂进水碳源不足的问题,采用中试规模的倒置AAO/MBR组合工艺,开展通过延长缺氧区水力停留时间以提高系统脱氮效果的研究。结果表明,延长缺氧区水力停留时间可强化反硝化菌对污水中慢速可降解有机碳源和内碳源的利用,可提高组合工艺的整体脱氮效率。当缺氧区水力停留时间从1.5 h增加到3.7 h,组合工艺出水TN可降低至9.25±2.13 mg/L;同时,系统CODCr和TP去除稳定,平均去除率分别稳定在93.12±3.29%和93.96±1.14%。
A pilot scale combined process of reversed AAO/MBR was constructed and proposed to investigate the strengthening effect of nitrogen removal by prolonging hydraulic retention time (HRT) in anoxic zone under condition of insufficient carbon source in municipal wastewater treatment plants. The results indicated that the utilization of slow degradable organic carbon and intracellular carbon by denitrifying bacteria could be strengthened with the prolongation of anoxic zone' s HRT. As a result, the nitrogen removal performance was enhanced. When the HRT of anoxic zone extends from 1.5 h to 3.7 h, TN of the effluent could be reduced to 9.25 ± 2.13 mg/L. In addition, the combined process had stable CODcr and TP removal ratios of 93.12% ± 3.29% and 93.96% ± 1.14%, respectively.