分配比对分段进水A2/O工艺脱氮除磷的影响

以低C/N实际污水为研究对象，研究进水分配比对分段进水A2/O工艺脱氮除磷性能的影响.以稳态条件下建立的物料平衡方程为基础，分析进水分配比对处理过程的影响.结果表明，分段进水A2/O工艺平均出水CODCr和NH3-N质量浓度基本维持为25.6～41.2 mg/L和0.35～1.40 mg/L，出水水质较稳定；出水TN、TP受进水分配比的影响明显.根据已建立的物料平衡方程分析发现，当进水分配比由6∶3降低至3∶6时，缺氧单元反硝化脱氮贡献率由36.95%升至83.47%，厌氧单元反硝化脱氮贡献率由43.81%降至12.30%，好氧单元同步硝化反硝化脱氮贡献率由19.24%降至4.23%，缺氧单元反硝化成为去除TN的主要途径，TN总体去除率升高9.95%；缺氧单元缺氧聚磷除磷贡献率由5.20%升至13.00%，好氧单元好氧聚磷除磷贡献率由94.80%降低至87.00%，好氧聚磷为去除TP的主要途径，但TP总体去除率降低5.37%.
Abstract: The low-C/N municipal wastewater was taken as the research object, and the influence of influent distribution ratio on nitrogen and phosphorus removal in A2/O step feed process was analyzed. The influence of influent distribution ratio on the treating process was analyzed based on the material balance equations established under steady-state conditions. Results showed that the average effluent mass concentrations of CODCr and NH3-N were maintained at 25.6-41.2 mg/L and 0.35-1.40 mg/L respectively, which were stable. The average effluent concentrations of TN and TP were obviously affected. The established material balance equations were analyzed. While the distribution ratio of influent was decreased from 6:3 to 3:6, the contribution rate of the denitrification in anoxia unit was increased from 36.95% to 83.47%, which in anaerobic unit was decreased from 43.81% to 12.30%, and the contribution rate of the simultaneous nitrification and denitrification in aerobic unit was decreased from 19.24% to 4.23%. The anaerobic denitrification became the main way to remove TN, and the general removal efficiency of TN was increased by 9.95%. The contribution rate of dephosphatation in anoxia unit was increased from 5.20% to 13.00%, which in aerobic unit was decreased from 94.80% to 87.00%. The aerobic dephosphatation was the main way to remove TP, and the general removal efficiency of TP was decreased by 5.37%.