膜-生物反应器中溶解性微生物产物的研究进展

Progress of studies on soluble microbial products in a membrane bioreactor

本文就膜 -生物反应器中溶解性微生物产物的生成特性及其影响的研究进展进行了总结。在膜 -生物反应器中 ,膜的高效固液分离作用在提高系统容积负荷和出水水质的同时 ,也使生物反应器成为一个相对封闭的系统。以腐殖质、多糖、蛋白质等物质为主要成分的溶解性微生物产物是生物处理出水中溶解性TOC或COD的主要组成部分 ,主要产生于微生物的基质分解过程和内源呼吸过程 ,其高分子物质的含量较多且可生物降解性较差 ,因此 ,在膜 -生物反应器中会出现积累。溶解性微生物产物的过高积累不仅有可能降低膜过滤出水的水质稳定性 ,而且有可能影响污泥活性 ,并引起膜污染。进水浓度和污泥浓度是影响溶解性微生物产物产生量的重要因素。目前有关膜 -生物反应器中溶解性微生物产物的研究还很不完善 。

A review concerning the production of soluble microbial products (SMP) and their impact in a membrane bioreactor is presented in this paper. The high performance of membrane separation in the membrane bioreactor not only results in an increased organic loading rate and an improved effluent quality, but also builds the bioreactor as a relatively closed system. SMP, most of which have been identified as humic acid, polysaccharide and protein released from substrate metabolism and microbial endogenous growth, are found to comprise the majority of soluble TOC or COD in the biologically treated effluent. SMP accumulation was always observed in a membrane bioreactor due to its considerable macromolecular content and its slow biodegradable nature. Too much accumulated SMP may decrease the stability of the effluent quality, repress microbial viability, as well as result in serious membrane fouling. SMP formation is greatly influenced by influent concentration and sludge concentration. The knowledge about SMP in a membrane bioreactor is far from completion. Much work is still required to be done.