以MTBE为目标污染物、乙醇为共代谢基质,在SBR反应器中成功实现了好氧污泥的颗粒化.反应器内污泥完全颗粒化后,MTBE进水浓度提高至400mg·mL-1左右,出水浓度可稳定在5mg·mL-1以下,去除率高达98.5%以上(其中挥发量约占25%).颗粒污泥结构致密,外观呈椭球形,表面微生物群落主要以球菌和短杆菌为主.序批实验表明,MTBE生物降解速率符合Michaelis-Menten方程,其单位时间内颗粒污泥(以干污泥计)降解MTBE的最大降解速率值为20.9mg·g^-1h^-1.PCR-DGGE图谱表明,颗粒污泥内微生物种群丰富,且稳定运行阶段微生物种群和结构可保持高度稳定.克隆测序结果表明,降解MTBE的好氧颗粒污泥反应器优势菌群主要为Flavobacteria、α-proteobacteria、γ-proteobacteria、Actinobacteria.
Aerobic granular sludge was cultivated in a Sequencing Batch Reactor(SBR)with Methyl Tertiary-Butyl Ether(MTBE)as a target pollutant,and ethanol as a co-substrate.After aerobic granulation,the effluent MTBE was below 5 mg·L^-1 and the removal efficiency was above 98.5%(about 25% via volatilization),although the influent MTBE concentration was increased to about 400 mg·L^-1.The stable granules had a spherical profile and compact structure with many different bacterial clusters.The surface of these clusters mainly consisted of cocci-like and short rod-like bacteria.Batch experiments showed that there was a good fit between the biodegradation rate and the Michaelis-Menten equation.The highest MTBE biodegradation rate was up to 20.9 mg·g^-1·h^-1.The fingerprint profile of PCR-DGGE indicated that the MTBE-degrading granules consisted of a wide diversity of microorganisms,and there was little change in the microbial communities during the stable operation period examined.The DNA sequencing results showed that the dominant organisms responsible for MTBE degradation were closely related to Flavobacteria、α-proteobacteria 、γ-proteobacteria and Actinobacteria.