硫自养微生物降解水中低浓度高氯酸盐的研究--反应器效能及微生物种群空间分布

Bio-reduction of perchlorate with low concentration in water by sulfur packed reactor and microbial community spacial distribution analysis

考察了升流式硫自养固定床反应器对水中低浓度高氯酸盐[(468.74±6.80)μg/L]的降解效能及相关机制,并利用高通量测序技术对反应器内微生物种群空间分布特性展开分析.研究发现,当HRT为4.00~0.75h时,高氯酸盐去除率达到97%以上,降解符合1/2级反应动力学模型,1/2K_(1/2v)为39.59[μg^(1/2)/(L1/2·h)].随着HRT由4.00h缩短至0.75h,出水SO_4^(2-)增量由173.37mg/L减小至90.07mg/L,由歧化反应产生的硫酸根占90.75%~93.91%,硫歧化反应与高氯酸盐的降解同步进行,同时,该反应也是碱度过量消耗的主要因素,导致出水p H值降低.测序结果表明,随着高度的增加,反应器内菌群α多样性降低.变形门(Proteobacteria)和绿菌门(Chlorobi)构成了反应体系的优势菌群.菌属Chlorobaculum为歧化反应菌属,是反应器内优势菌属.

Removal of perchlorate with low concentration[(468.74±6.80)μg/L]in water was investigated by an up-flow sulfur autotrophic reduction reactor.And bacterial community spatial distribution was analyzed by High-throughput sequencing method.The reactor could be operated at a hydraulic retention time(HRT)ranging in4.00~0.75h with a remarkable removal efficiency greater than97%.1/2-order kinetics model fit the experimental data well;and1/2K1/2v was39.59[μg1/2/(L1/2?h)].When HRT shortened from4.00h to0.75h,the generated SO42-decreased from173.37to90.07mg/L.Sulfur(S)disproportionation was accompanied with perchlorate reduction;the proportion of SO42-generated by S-disproportionation was in range of90.75%~93.91%.Meanwhile,S-disproportionation was the main reason for excess consumption of alkalinity,thus leading to pH decreases in effluent.The sequencing results showed that theα-biodiversity was decreased along the height of reactor.The Proteobacteria and Chlorobi was observed as the major bacteria,and the Chlorobaculum was the dominant bacteria associated with S-disproportionation.