Tomato paste processing produces lots of wastewater in Xinjiang region andpart has not treated efficiently.To solve this problem,flocculent sludge was fed with synthetic tomato paste processing wastewater in a sequencing batch reactor(SBR). Aerobic granular sludge with diameters from 0. 50-1. 61 mm was successfully cultivated. The combined bio-analytical techniques of scanning electron microscopy (SEM), 3-D excitation emission matrices (3D EEM), confocal laser scanning microscopy (CLSM), live∕dead staining and highthroughput sequencing were used to characterize the granulation process of activated sludge. The results suggested that the aerobic granules had a good settling ability. The average removal rate of CODCr, NH4 + -N, PO4 3- -P reached 90%, 85% and 45%, respectively.Observation by SEM showed that ellipsoidal granule had a clear outline and compacting structure. The concentration of protein in EPS increased gradually. Inaddition, α-D-glucopyranose polysaccharide, β-D-glucopyranoe polysaccharide and protein, as components of EPS,widely distributed throughout the whole granule, which constructed the framework of the granule. The pores in the granule provided the passageways for delivery of dissolved oxygen and nutrients, therefore the live bacteria distributed more closely to the edge of the granule and pores, with dead bacteria wrapped inside. During the process of granulation, microbial diversity varied when species richness and evenness gradually increased. Chao 1 index decreased from 515. 26 to 444. 30 then back to 526. 72. Shannon-Wiener index increased from 2. 81 to 5. 45. As dominant degrading bacteria groups, the relative abundance of Bacteroides increased from 8. 85% to 45. 95% while that of Proteobacteria decreased from 78. 17% to 36. 66%. The study demonstrated the interaction of different bacterial populations plays an important role on the degradation of organics and the stability of reaction system.%为解决新疆番茄酱加工废水排放量大、处理效果参差不齐的情况,在SBR(序批式反应器)中接种絮体污泥,以人工合成番茄酱加工废水为基质成功培养出粒径为0.50~1.61 mm的好氧颗粒污泥,并采用扫描电镜、三维荧光光谱(3D EEM)、激光共聚焦(CLSM)、死活细菌染色以及高通量测序等技术表征活性污泥的颗粒化过程.结果表明,颗粒污泥沉降性能良好,CODCr、NH4+-N、PO43--P 的平均去除率分别为90%、85%、45%.扫描电镜下,椭球状的颗粒污泥轮廓清晰,结构密实.蛋白质在颗粒化过程中逐渐增加,α-多糖、β-多糖和蛋白质贯穿整个颗粒截面,在颗粒中分布广泛,构成了颗粒的骨架.颗粒内部的孔隙为溶解氧和营养物质传递提供了条件,因此活细菌则更多地靠近颗粒边缘及内部的孔隙周围,并包裹着死细菌.颗粒化过程中,微生物的丰富度和均匀性逐渐上升,物种多样性也不断变化,Chao1指数先由515.26降至444.30后又增至526.72,Shannon-Wiener指数由2.81增至5.45.优势降解菌拟杆菌和变形菌相对丰度不断发生变化,拟杆菌由8.85%增至45.95%,而变形菌由78.17%逐渐减至36.66%.研究显示,不同的细菌种群之间的相互作用对有机物的降解以及反应体系的稳定起到重要的作用.
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