溶解氧对一体式膜生物反应器(IMBR)的影响

针对溶解氧(DO)和气水比对IMBR工艺出水效果的影响及能耗问题,从气水比对DO的影响和DO对COD与NH3-N去除效果的影响着手,探讨研究气水比、溶解氧以及污水处理效果之间的最佳工作点。试验结果表明,在ρ(MLSS)分别为4.23,4.09,3.70g/L的运行条件下,MBR的最佳运行气水比相应为35∶1,25∶1,17∶1;溶解氧变化速率随污泥浓度的下降而升高;DO的变化对COD的去除效果并不显著;在高污泥浓度下,DO的质量浓度保持在2.63～4.85mg/L之间时,氨氮的去除率随溶解氧浓度的上升而下降,氨氮去除率达90%以上;但DO浓度过低时,氨氮去除效果不佳。

Effects of Dissolved Oxygen on Integrated Membrane Bioreactor

In view of the effects of dissolved oxygen(DO)and air-water ratio on the results of the effluent water with IMBR process as well as the energy consumption, and starting with the effects of air-water ratio on DO and the effects of DO on the removal of COD and NH3-N, an approach was made to the optimum working point in studying the relations among air-water ratio, dissolved oxygen and result of treatment of waste water. It was shown by the results of tests that under the operating conditions that ρ(MLSS)was 4.23, 4.09 and 3.70 g/L respectively, the optimum corresponding operating air-water ratios of MBR were 35∶1, 25∶1 and 17∶1; the variation rate of dissolved oxygen was increasing with the decreasing of sludge concentration; the effects of the variation of DO on the result of removal of COD was not significant; with high sludge concentration and when DO concentration was maintained between 2.63 ～ 4.85 mg/L, the ammonia-nitrogen removal rate decreased with the increase of the concentration of dissolved oxygen while ammonia-nitrogen removal rate reached 90% or above; but when the DO concentration was too low, the removal rate of ammonia nitrogen was not good.