藻-菌颗粒污泥的污染物去除和微生物群落演替研究

Study on pollutant removal and microbial community succession of algae-bacteria granular sludge

通过比较好氧颗粒污泥(AGS)与藻-菌颗粒污泥(ABGS)两组SBR反应器,旨在评价微藻的加入对污染物去除和微生物群落的影响.结果表明,微藻的生物强化作用会加速活性污泥颗粒化.同时,ABGS对PO_(4)^(3-)P和总无机氮的平均去除率比AGS分别高5.3%和16.3%,这可归因于微藻对污染物的同化作用.16S rRNA结果进一步发现,变形菌门(Proteobacteria)和拟杆菌门(Bacteroidetes)是主要两个生物反应器中的优势菌,然而,由于微藻的增殖和代谢作用,绿弯菌门(Chloroflexi)、浮霉菌门(Planctomycetes)和疣微菌门(Verrucomicrobia)在藻-菌颗粒污泥中的丰度被发现远高于好氧颗粒污泥中.此外,18S rRNA结果显示,初始接种的蛋白核小球藻(Chlorella pyrenoidesa)被快速生长的四孢藻属(Tetraspora)所取代,致使藻-菌颗粒污泥比好氧颗粒污泥展现了更好的氮、磷去除率.

In this work,two SBR reactors composed of aerobic granular sludge(AGS)and algae-bacterial granular sludge(ABGS)were individually operated to evaluate the effects of microalgae on pollutant removal and microbial community.The results showed that the bio-enhancement of microalgae could accelerate the granulation process of activated sludge.Meanwhile,the average removal efficiency of PO_(4)^(3-)-P and total inorganic nitrogen in ABGS bioreactor was 5.3%and 16.3%higher than that in AGS bioreactor,which could be attributed to the assimilation of pollutants by microalgae.The results of 16S rRNA further revealed that Proteobacteria and Bacteroidetes were most dominate phyla in both two bioreactors,whereas,the relative abundances of Chloroflexi,Planctomycetes and Verrucomicrobia in the ABGS were much higher than those in AGS due to the proliferation and metabolism of microalgae.Moreover,18S rRNA results showed that the initially inoculated Chlorella pyrenoidesa was replaced by Tetraspora which rapidly grew in the ABGS bioreactor,contributing to the better removal efficiencies of nitrogen and phosphorus in ABGS bioreactor than AGS bioreactor.