铁钙离子共存体系对MBR运行影响研究

Influence Research of the Coexistence of Iron and Calcium Ion on the Performance of Membrane Bioreactor

本文针对了膜生物反应器(membrane bioreactor,MBR)污泥混合液在铁钙离子共存情况下对MBR运行的影响进行研究。实验结果表明:不同比例的铁钙离子共存时,COD、NH3-N、TP的去除率分别高达94%、98%、98%以上;进一步研究发现,对于调控MBR混合液存在最佳的铁钙离子比,当铁钙离子比为1∶3时,最大程度延缓了膜污染速率;钙离子的加入,MBR混合液中溶解性微生物产物(soluble microbial products,SMP)浓度降低明显,其中SMP中多聚糖含量与钙离子浓度密切相关;在铁钙离子共存体系,钙离子含量对松散结合态EPS(loosely bound EPS,LB)浓度影响较大,对紧密结合态EPS(tightly bound,TB)影响不显著。

In this paper, the effect of the coexistence of iron and calcium on the performance of membrane bioreactor （MBR） was investigated. The experimental results showed that the average removal rate of COD, NH3-N and TP maintained high and stable level at the different ratio of iron and calcium, which were about 94% , 98% and 98% , respectively. The membrane fouling rate was significantly decreased when the ratio of iron and calcium was 1：3. With the help of calcium ions, the concentration of soluble microbial products（SMP） in MBR decreased obviously, especially to the polysaccharide in SMP. It was reported that the concentration of SMP polysaecharide was closely related with the calcium ion. By the analysis of extracellular polymeric substances （EPSs） , it was also found that the ratio of iron and calcium had a great effect on the loosely bound EPSs （LB-EPSs） concentration, however, which had no obviously relationship with the amount of tightly bound EPSs （TB-EPSs）.