title: Bioaggregate of photo-fermentative bacteria for enhancing continuous hydrogen production in a sequencing batch photobioreactor.
abstract: Hydrogen recovery through solar-driven biomass conversion by photo-fermentative bacteria (PFB) has been regarded as a promising way for sustainable energy production. However, a considerable fraction of organic substrate was consumed for the growth of PFB as biocatalysts, furthermore, these PFB were continuously washed out from the photobioreactor in continuous operation because of their poor flocculation. In this work, PFB bioaggregate induced by L-cysteine was applied in a sequencing batch photobioreactor to enhance continuous hydrogen production and reduce biomass washout. The effects of the hydraulic retention time (HRT), influent concentration and light intensity on hydrogen production of the photobioreactor were investigated. The maximum hydrogen yield (3.35 mol H2/mol acetate) and production rate (1044 ml/l/d) were obtained at the HRT of 96 h, influent concentration of 3.84 g COD/l, and light intensity of 200 W/m(2). With excellent settling ability, biomass accumulated in the photobioreactor and reached 2.15 g/l under the optimum conditions. Structural analysis of bioaggregate showed that bacterial cells were covered and tightly linked together by extracellular polymeric substances, and formed a stable structure. Therefore, PFB bioaggregate induced by L-cysteine is an efficient strategy to improve biomass retention capacity of the photobioreactor and enhance hydrogen recovery efficiency from organic wastes.
authors.affiliation: State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China.|Advanced Water Management Centre, The University of Queensland, QLD 4072, Australia.
authors.forename: Guo-Jun
authors.initials: GJ
authors.lastname: Xie
authors.affiliation: State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China.
authors.forename: Bing-Feng
authors.initials: BF
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China.
authors.forename: Rui-Qing
authors.initials: RQ
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China.
authors.forename: Jie
authors.initials: J
authors.lastname: Ding
authors.affiliation: State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China.
authors.forename: Hong-Yu
authors.initials: HY
authors.lastname: Ren
authors.affiliation: Advanced Water Management Centre, The University of Queensland, QLD 4072, Australia.
authors.forename: Xu
authors.initials: X
authors.lastname: Zhou
authors.affiliation: State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China.
authors.forename: Nan-Qi
authors.initials: NQ
authors.lastname: Ren
mesh_terms: D018533:Biomass; D002126:Calcium Hydroxide / Q000378:metabolism*; D003545:Cysteine / Q000378:metabolism; D005285:Fermentation / Q000502:physiology*; D005427:Flocculation; D006859:Hydrogen / Q000378:metabolism*; D006882:Hydroxyapatites / Q000378:metabolism*; D008027:Light; D058433:Photobioreactors / Q000382:microbiology*; D012241:Rhodopseudomonas / Q000378:metabolism / Q000502:physiology*; D012722:Sewage / Q000382:microbiology; D017640:Silicates / Q000378:metabolism*
chemical_list: C557009:BioAggregate; D006882:Hydroxyapatites; D012722:Sewage; D017640:Silicates; D006859:Hydrogen; D003545:Cysteine; D002126:Calcium Hydroxide