title: Variations of organic matters and microbial community in thermophilic anaerobic digestion of waste activated sludge with the addition of ferric salts.
abstract: Ferric salts will influence the thermophilic anaerobic digestion of waste activated sludge (WAS). FeCl3 was found to contribute to the anaerobic digestion process with a cumulative biogas production of 357 mL/gVS, 79.6% higher than that in the control group, and Fe2(SO4)3 had no distinct impact, while Fe(NO3)3 inhibited the methanogenesis process. A favorable balance between the release of organic matters from WAS and consumption rate was established after dosing FeCl3 from the perspective of variations of soluble COD, volatile fatty acids (VFAs) and the dissolved organic matters (DOM) assessed by EEM fluorescence spectroscopy and fluorescence regional integration (FRI) technique. Conversely, the system with Fe(NO3)3 achieved an unsuitable substrates environment. Pyrosequencing revealed that the anaerobic digestion system with FeCl3 enriched Coprothermobacter for proteins fermentation and Methanosarcina for methanogenesis with the values of 18.7% and 63.2%, respectively, while that with the supplementation of Fe(NO3)3 obtained the lowest relative abundance.
authors.affiliation: School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China.
authors.forename: Bao
authors.initials: B
authors.lastname: Yu
authors.affiliation: School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China.
authors.forename: Ziyang
authors.initials: Z
authors.lastname: Lou
authors.affiliation: School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China.
authors.forename: Dongling
authors.initials: D
authors.lastname: Zhang
authors.affiliation: School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China.
authors.forename: Aidang
authors.initials: A
authors.lastname: Shan
authors.affiliation: School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China.
authors.forename: Haiping
authors.initials: H
authors.lastname: Yuan
authors.affiliation: School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China. Electronic address: nwzhu@sjtu.edu.cn.
authors.forename: Nanwen
authors.initials: N
authors.lastname: Zhu
authors.affiliation: National Key Laboratory of Human Factors Engineering, China Astronaut Research and Training Center, Beijing 100094, China.
authors.forename: Kanghan
authors.initials: K
authors.lastname: Zhang
mesh_terms: D000693:Anaerobiosis / Q000187:drug effects; D001105:Archaea / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D001419:Bacteria / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D056804:Biofuels / Q000382:microbiology; D001682:Biological Availability; D019149:Bioreactors / Q000382:microbiology; D015723:Gene Library; D019766:Genes, Archaeal; D005798:Genes, Bacterial; D007501:Iron / Q000494:pharmacology*; D009930:Organic Chemicals / Q000032:analysis*; D012492:Salts / Q000494:pharmacology*; D012722:Sewage / Q000382:microbiology*; D013050:Spectrometry, Fluorescence; D013696:Temperature; D014835:Volatilization
chemical_list: D056804:Biofuels; D009930:Organic Chemicals; D012492:Salts; D012722:Sewage; D007501:Iron
keywords: Dissolved organic matters; EEM fluorescence spectroscopy; Ferric salts; Methanosarcina; Waste activated sludge