title: Selective simplification and reinforcement of microbial community in autothermal thermophilic aerobic digestion to enhancing stabilization process of sewage sludge by conditioning with ferric nitrate.
abstract: The effect of ferric nitrate on microbial community and enhancement of stabilization process for sewage sludge was investigated in autothermal thermophilic aerobic digestion. The disinhibition of volatile fatty acids (VFA) was obtained with alteration of individual VFA concentration order. Bacterial taxonomic identification by 454 high-throughput pyrosequencing found the dominant phylum Proteobacteria in non-dosing group was converted to phylum Firmicutes in dosing group after ferric nitrate added and simplification of bacteria phylotypes was achieved. The preponderant Tepidiphilus sp. vanished, and Symbiobacterium sp. and Tepidimicrobium sp. were the most advantageous phylotypes with conditioning of ferric nitrate. Consequently, biodegradable substances in dissolved organic matters increased, which contributed to the favorable environment for microbial metabolism and resulted in acceleration of sludge stabilization. Ultimately, higher stabilization level was achieved as ratio of soluble chemical oxygen demand to total chemical oxygen demand (TCOD) decreased while TCOD reduced as well in dosing group comparing to non-dosing group.
authors.affiliation: School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China.
authors.forename: Ningben
authors.initials: N
authors.lastname: Jin
authors.affiliation: School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China.
authors.forename: Zongqi
authors.initials: Z
authors.lastname: Shou
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.
authors.forename: Ziyang
authors.initials: Z
authors.lastname: Lou
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
mesh_terms: D000332:Aerobiosis; D057919:Biological Oxygen Demand Analysis; D019149:Bioreactors / Q000382:microbiology*; D005232:Fatty Acids, Volatile / Q000378:metabolism; D005290:Ferric Compounds / Q000494:pharmacology*; D006094:Gram-Positive Bacteria / Q000187:drug effects* / Q000254:growth & development / Q000378:metabolism; D009566:Nitrates / Q000494:pharmacology*; D009584:Nitrogen / Q000032:analysis; D012722:Sewage / Q000737:chemistry*; D013696:Temperature; D018505:Waste Management / Q000379:methods*; D018508:Water Purification
chemical_list: D005232:Fatty Acids, Volatile; D005290:Ferric Compounds; D009566:Nitrates; D012722:Sewage; D009584:Nitrogen; C025302:ferric nitrate
keywords: Autothermal thermophilic aerobic digestion; Dissolved organic matters; Ferric nitrate; Microbial community; Volatile fatty acids