title: Start-up of bio-hydrogen production reactor seeded with sewage sludge and its microbial community analysis.
abstract: Start-up of a continuously stirred tank reactor for bio-hydrogen production under different initial organic loading rate (OLR) of 3, 7 and 10 kgCOD/m3 d, respectively, was carried out with sewage sludge as inoculum. Molasses wastewater was used as substrate and hydraulic retention time was kept at 6 h. This study aimed to assess OLR on the formation of fermentation types and the structure of microbial communities during the start-up period. It was found that at an initial OLR of 7 kgCOD/m3 d and an initial biomass of 6.24 gVSS/L, an equilibrial microbial community of ethanol-type fermentation could be established within 30 days. The observed average specific hydrogen production rate was 276 mLH2/gVSS d, which was 40% higher than that of the one acclimated with 3 kgCOD/m3 d. Based on denaturing gradient gel electrophoresis profiles, significant microbial population shifts took place at the first 15 days, but a longer period up to 30 days was required to establish a microbial community with stable metabolic activity.
authors.affiliation: School of Municipal and Environmental Engineering, Harbin Institute of Technology, Nangang District, Harbin 150090, China.
authors.forename: M L
authors.initials: ML
authors.lastname: Gong
authors.forename: N Q
authors.initials: NQ
authors.lastname: Ren
authors.forename: D F
authors.initials: DF
authors.lastname: Xing
mesh_terms: D001419:Bacteria / Q000235:genetics / Q000302:isolation & purification*; D019149:Bioreactors / Q000382:microbiology*; D004269:DNA, Bacterial / Q000032:analysis; D004275:DNA, Ribosomal / Q000032:analysis; D000431:Ethanol / Q000378:metabolism; D005232:Fatty Acids, Volatile / Q000378:metabolism; D005285:Fermentation; D006859:Hydrogen / Q000378:metabolism*; D007220:Industrial Waste; D008965:Molasses; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D012722:Sewage / Q000382:microbiology*; D014865:Waste Disposal, Fluid
chemical_list: D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D005232:Fatty Acids, Volatile; D007220:Industrial Waste; D012336:RNA, Ribosomal, 16S; D012722:Sewage; D000431:Ethanol; D006859:Hydrogen