title: Succession of microbial community and enhanced mechanism of a ZVI-based anaerobic granular sludge process treating chloronitrobenzenes wastewater.
abstract: The combined zero-valent iron (ZVI) and upflow anaerobic sludge blanket (UASB) process is established for the treatment of chloronitrobenzenes (ClNBs) wastewater, and the succession of microbial community and its enhanced mechanism are investigated in the study. Results showed that compared with the control UASB (R1), the stable COD removal, ClNBs transformation, and dechlorination occurred in the combined system (R2) when operated at influent COD and 3,4-Dichloronitrobenzene (3,4-DClNB) loading rates of 4200-7700 g m(-3) d(-1) and 6.0-70.0 g m(-3) d(-1), and R2 had the better shock resistance and buffering capacity for the anaerobic acidification. The dechlorination for the intermediate products of p-chloroanaline (p-ClAn) to analine (AN) occurred in R2 reactor after 45 days, whereas it did not occur in R1 after a long-term operation. The novel ZVI-based anaerobic granular sludge (ZVI-AGS) was successfully developed in the combined system, and higher microbial activities including ClNB transformation and H2/CH4 production were achieved simultaneously. The dominant bacteria were closely related to the groups of Megasphaera, Chloroflexi, and Clostridium, and the majority of archaea were correlated with the groups of Methanosarcinalesarchaeon, Methanosaetaconcilii, and Methanothrixsoehngenii, which are capable of reductively dechlorinating PCB, HCB, and TCE in anaerobic niche and EPS secretion.
authors.affiliation: Department of Environmental Engineering, Zhejiang University, Hangzhou 310058, China; Zhejiang Province Key Laboratory for Water Pollution Control and Environmental Safety, Hangzhou 310058, China. Electronic address: felix79cn@hotmail.com.
authors.forename: Liang
authors.initials: L
authors.lastname: Zhu
authors.affiliation: Department of Environmental Engineering, Zhejiang University, Hangzhou 310058, China.
authors.forename: Jie
authors.initials: J
authors.lastname: Jin
authors.affiliation: Department of Environmental Engineering, Zhejiang University, Hangzhou 310058, China; Wenzhou Environmental Protection Design Scientific Institute, Wenzhou 325000, China.
authors.forename: Haizhuan
authors.initials: H
authors.lastname: Lin
authors.affiliation: Department of Environmental Engineering, Zhejiang University, Hangzhou 310058, China.
authors.forename: Kaituo
authors.initials: K
authors.lastname: Gao
authors.affiliation: Department of Environmental Engineering, Zhejiang University, Hangzhou 310058, China; Zhejiang Province Key Laboratory for Water Pollution Control and Environmental Safety, Hangzhou 310058, China. Electronic address: xuxy@zju.edu.cn.
authors.forename: Xiangyang
authors.initials: X
authors.lastname: Xu
mesh_terms: D000693:Anaerobiosis; D001105:Archaea / Q000235:genetics / Q000378:metabolism; D001419:Bacteria / Q000235:genetics / Q000378:metabolism; D019149:Bioreactors; D019641:DNA, Archaeal / Q000032:analysis; D004269:DNA, Bacterial / Q000032:analysis; D007501:Iron / Q000378:metabolism*; D009578:Nitrobenzenes / Q000378:metabolism*; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D012722:Sewage / Q000382:microbiology; D014865:Waste Disposal, Fluid; D062065:Wastewater; D014874:Water Pollutants, Chemical / Q000378:metabolism*
chemical_list: D019641:DNA, Archaeal; D004269:DNA, Bacterial; D007501:Iron; D009578:Nitrobenzenes; D012336:RNA, Ribosomal, 16S; D012722:Sewage; D062065:Wastewater; D014874:Water Pollutants, Chemical
keywords: Anaerobic granular sludge; Chloronitrobenzenes (ClNBs); Dechlorination; Microbial community; Zero-valent iron (ZVI)