膜生物反应器的运行和膜污染特征

Membrane Fouling Characteristics and Fouling Control Methods in Membrane Bioreactors

研究了膜生物反应器的运行效果、膜污染特征。结果表明:膜生物反应器具有良好的污染物去除效果,在处理生活污水时COD的去除率达到90%以上,出水COD控制在80 mg.L-1以下,NH4-N的去除效果能达到95%,出水NH4-N浓度10 mg.L-1以下,膜污染的过程呈现明显的"两段式"特点,即过膜压力缓慢上升阶段和快速上升阶段。采用NaOH+NaClO联合清洗后,膜的过膜压力迅速下降,表明膜污染以有机污染为主。

The paper present an experimental study on the performance and characteristics of the membrane fouling in membrane bioreactor （MBR） operation. The result showed that MBR had excellent removal efficiency, when treating the municipal wastewater, the COD removal could arrival above 90 %, the COD concentration of effluent was below 80 mg/L, the NH4-N removal efficiency could be 95 %, the concentration of NH4-N of effluent was below 10 mg·L^-1. The membrane fouling rate increased as time extended, and the membrane fouling course appeared ＂two stage＂, one stage was the stage of trans-membrane pressure（TMP） maintained stable and the other stage was the stage of TMP rise quickly. Afier cleaning by NaOH ＋ NaCIO mixed solution, the TMP decreased greatly, which showed that the main type of the membrane fouling was organic pollutants.