MPSR无污泥外排系统长期运行机制分析

针对日益凸显的剩余污泥产量大、处置难的问题,实验采用微压内循环生物反应器(MPSR)在无污泥外排运行方式下处理污水.MPSR的有效容积为36L,序批式运行,运行参数为曝气量0.14m³/h,排水比50%,循环周期12h,进水温度(20±1) ℃,连续运行225d.实验结果表明,MPSR具有良好的污染物去除效果,COD、TP、NH₄⁺-N、TN的平均去除率分别达到85%、95%、95%、75%.活性污泥SVI、EPS和生物相结果表明,无污泥外排MLSS大量增长下污泥仍具有高效沉降稳定性.由高通量测序分析可知,系统菌群具有较高的稳定性且稳定期具有丰度更高的脱氮除磷功能菌群,保证了无污泥外排MPSR系统可长期序批式运行和系统高效的污染物降解能力.

Analysis of the long-term operation mechanism of MPSR sludge-free discharge system

In response to the increasingly prominent problems of large residual sludge output and difficult disposal, the experiment used a micro-pressure swirl reactor (MPSR) to treat sewage in a sludge-free discharge mode. MPSR had an effective volume of 36L and ran in batch mode. The operating parameters were aeration rate of 0.14m³·h^-1, drainage ratio of 50%, operation period of 12h, and the inlet temperature was (20±1)℃, continuous operation for 225d. The experimental results showed that MPSR had a good pollutant removal effect, the average removal rates of COD, TP, NH₄⁺-N, and TN reached 85%, 95%, 95%, and 75%, respectively. During the operation, the stability of SVI, microscopic examination and the substantial reduction of EPS showed that the system did not have filamentous bacteria and extracellular polymer secretions, which ensured that the sludge still had high-efficiency settling viscosity conditions under the large increase of sludge-free MLSS. High-throughput sequencing analysis showed that the system had high stability and higher abundance of nitrogen and phosphorus removal in the stable period, which ensured the long term sequential batch operation of the sludge-free MPSR system and the high efficiency of pollutant degradation.