膜生物反应器处理含盐生活污水的研究

Research on treatment of saline domestic sewage by membrane bioreactor

试验采用膜生物反应器处理不同盐度的生活污水。在进水CODMn为47．4～112．4mg·L^-1、NH3-N为27．5～49．7mg·L^-1、TN为35．2～57．1mg·L^-1、pH为6．0～8．0，DO为2．8—6．2mg·L^-1、MISS为5880-6823mg·L^-1、温度为20～27℃的条件下，当进水盐度分别为0．5％（即含盐量为5g·L^-1）、1．0％、1．5％时，CODMn的平均去除率分别为88．1％、85．1％、84．0％；NH3-N的平均去除率分别为91．9％、90．6％、89．7％；TN平均去除率分别为47．1％、41．1％、35．7％。在同一盐度时，所测各项指标大都是先下降后升高，最后趋于平稳。但从总体来看，随着盐度升高，COD、NH—N和TN的去除率和MISS均呈下降趋势。高盐度环境下微生物所分泌的大量胞外聚合物是造成膜污柒的主要原因。

Membrane bioreactor technology was used to treat the different salinity of domestic sewage under the conditions of CODMn, of 47.4 - 112.4 mg· L^- 1, NH3 - N of 27.5 - 49.7 mg· L^- 1, TN of 35.2 - 57.1 mg· L^- 1, pH of 6.0 - 8.0, DO of 2.8 - 6.2 mg· L^- 1, MISS of 5880 - 6823 mg· L^- 1, temperature of 20 -27 ℃. The results show that average removal rate of CODMn is 88.1%, 85.1%, 84.0%, respectively, average removal rate of NH3 - N is 91.9%, 90.6%, 89.7%, and average removal rate of TN is 47.1%, 41.1%, 35.7 % respectively, when the salinity of the sewage is 0.5 %, 1.0% and 1.5 %, respectively. Under the same salinity, the items monitored first decrease and then show a stable trend after the rise,. On the whole, the removal rate of COD, NH3 - N, TN and MLSS all decline with salinity increasing. The extracellular polymeric substance（EPS） excreted by microorganisms under the high salinity conditions is mainly responsible for membrane fouling.