碳磷比对SND过程污染物去除及N2O释放的影响

以两个平行运行的SBR反应器为研究对象,研究了碳磷比对同步硝化反硝化过程中污染物去除及温室气体N2O释放的影响.结果表明:系统对COD和氨氮的去除率均能达到90%以上,总磷和总氮去除率随碳磷比的降低而提高,这是由于低碳磷比下聚磷菌得到富集,同时部分聚磷菌利用NO3-和NO2-为电子受体吸收磷,从而实现脱氮除磷的同步提高.系统的N2O释放量随碳磷比的降低而降低,低碳磷比下N2O释放量仅为高碳磷比的76%.低碳磷比下N2O释放量的减少主要是由于异养反硝化过程对N2O释放的贡献降低导致的.

Effects of COD/P ratio on contaminant removal and N2O emission during simultaneous nitrification and denitrification process

Two parallel anaerobic-aerobic SBRs were conducted to evaluate the impacts of different COD/P ratio on contaminant removal and nitrous oxide (N2O) emission during simultaneous nitrification and denitrification (SND) process. The results showed that the removal efficiencies of COD and ammonium were more than 90% in both SBRs. TP and TN removal was enhanced simultaneously with the decrease of COD/P ratio. It was mainly caused by the enrichment of polyphosphate accumulating organisms (PAOs) at low COD/P ratio. Part of PAOs could use nitrate/nitrite as electron acceptors to take up the phosphorus. N2O emission was reduced with the decrease of COD/P ratio. The N2O emission amount per cycle at low COD/P ratio was only 76% of that at high ratio. It was due to the decrease of N2O yield by heterotrophic denitrification.