AFMBR处理低浓度废水的运行特性

Characteristics of anaerobic fluidized bed membrane bioreactor for dilute wastewater Treatment

采用厌氧流化床膜生物反应器(AFMBR)处理模拟生活污水,研究其启动运行的特性.结果表明,在室温、进水COD 270mg/L的条件下,AFMBR系统经过驯化富集后,其出水SCOD能稳定维持在30mg/L以下,冬季温度降低时,系统产甲烷菌的活性会受到抑制,出水SCOD在30~40mg/L,但仍可满足一级A排放标准.系统的总甲烷转化量在0.182L/g COD去除左右,温度越高气体甲烷的转化量越大,进水COD约有45%转化为甲烷.AFMBR系统连续运行218d的污泥产量为0.071g VSS/g COD,其值要远远低于典型好氧系统的污泥产量.系统的能耗及产能,若只考虑气态甲烷产能,本研究中当HRT降至10h时产能才能满足能耗需求;若考虑所有的甲烷产能,当HRT降至20h时产能即能满足能耗需求,当HRT降至10h时产能是能耗需求的2倍.因此,AFMBR作为一个低耗高效的废水处理系统,具有良好应用潜力.

Anaerobic fluidized bed membrane bioreactor （AFMBR） with simulated domestic wastewater was studied at room temperature. With the influent COD of 270mg/L, AFMBR system operated through acclimation and enrichment. The effluent SCOD could remain stable under 30mg/L. With the decrease of temperature in winter, the effluent SCOD was between 30and 40mg/L as the activity of anaerobic transformation, such as methanogenic bacteria, in the system might be inhibited, but the level A Emission Standard could still be meet. The total methane conversion amount was about 0.182L/g CODR, about 45% of the influent COD conversion to methane. The sludge production of the AFMBR system for 218days operation continuously was 0.071g VSS/g COD, which was much lower than the typical aerobic one. As for the net energy output of the system, if the gaseous methane production was only considered, the energy demand for mechanic power could be met when the HRT was reduced to 10h; if all the methane production was taken into account, the energy demand could be met when the HRT was reduced to 20h. When the HRT was reduced to 10h, the energy output was twice over the energy demand. Thus, the AFMBR system had great potential as an energy positive wastewater treatment system.