混合液回流比对膜工艺处理效果影响的研究

Study on the Effect of Mixed Liquid Recycle Ratio on Membrane Process

以混合型城市污水为研究对象,采用膜生物反应器强化脱氮除磷集成工艺,探讨了不同混合液回流比对该工艺脱氮除磷的影响.结果表明,混合液回流比对COD、NH3-N影响不大;随着回流比的增大,TN的平均去除率逐渐提高,当回流比从1.5增加到2.0时,随着回流比的增加去除率明显增大,由2.0增加到3.0时,增加幅度有限;TP的平均去除率随回流比先增大后减小,在回流比为2.0时TP平均去除率最大.综合考虑,该工艺的最佳回流比为2.0.

In order to discuss the nitrogen and phosphorus removal effect under different reflux ratio in the process,the mixed municipal wastewater was used as the research object and the membrane bioreactor process of enhanced nitrogen and phosphorus removal was used to do the pilot study. The results show that, mixed liq uid recycle ratio had little effect on COD,NH3N removal; when the reflux ratio increased,the average removal rate of TN increased gradually,while the reflux ratio increasing from 0.5 to 2, the removal rate increased signif icantly, and while increasing from 2 to 3, the increased amplitude was limited. With reflux ratio increasing , the average removal rate of TP increased first and then decreased,when the reflux ratio was 2,the average removal rate of TP was largest. On comprehensive consideration,the optimum reflux ratio of the process is 2.