超长污泥龄对MPR工艺脱氮除磷效果的影响

针对高MLSS下系统的稳定运行及脱氮除磷效果,采用微压内循环生物相反应器(MPR)处理模拟城市污水,探究了超长污泥龄(SRT)在50、70、90d时,MPR不断减少剩余污泥排放量下的脱氮除磷效果.结果表明,当SRT由50d提升至90d时,MPR工艺的脱氮能力得到增强,TN的平均去除率由75.97％提高到84.60％.在...

Effects of ultra-long sludge rentention time on denitrification and phosphorus removal by MPR process

In this study, aiming at the stable operation of the system and the effect of denitrification and phosphorus removal under the high MLSS, the Micro-Pressure Inner-Loop Bioreactor (MPR) was used to treat simulated urban sewage, and its effects of denitrification and phosphorus removal under the condition of the continuous reduction of residual sludge discharge at SRTs of 50, 70 and 90 days. The results showed that when SRT increased from 50 d to 90 d, the denitrification performance of MPR process was strengthened, and the average removal rate of TN increased from 75.97% to 84.60%. At the same time, after SRT was extended, the TP removal rate of MPR process decreased, but the TP removal rate was stably over 97%, and ultra-long SRT had slight effect on TP removal. When SRT was 90 d, the average MLSS and SVI during stability period of the system were 13 252 mg·L−1 and 70 mL·g−1, respectively. At this time, the system had the best performance on denitrification and phosphorus removal. The average effluent mass concentrations of COD, $ {rm{NH}}_4^ + $-N, TN, TP were 24.73, 0.49, 6.99, 0.07 mg·L−1, respectively, and the water quality of effluent was better than the GB18918-2002 grade A standard. The study shows that under the ultra-long SRT, the MPR system can not only run stably for a long time, but also ensure high denitrification and phosphorus removal effects.