title: Enhancement of bioenergy production from organic wastes by two-stage anaerobic hydrogen and methane production process.
abstract: The present study investigated a two-stage anaerobic hydrogen and methane process for increasing bioenergy production from organic wastes. A two-stage process with hydraulic retention time (HRT) 3d for hydrogen reactor and 12d for methane reactor, obtained 11% higher energy compared to a single-stage methanogenic process (HRT 15 d) under organic loading rate (OLR) 3 gVS/(L d). The two-stage process was still stable when the OLR was increased to 4.5 gVS/(Ld), while the single-stage process failed. The study further revealed that by changing the HRT(hydrogen):HRT(methane) ratio of the two-stage process from 3:12 to 1:14, 6.7%, more energy could be obtained. Microbial community analysis indicated that the dominant bacterial species were different in the hydrogen reactors (Thermoanaerobacterium thermosaccharolyticum-like species) and methane reactors (Clostridium thermocellum-like species). The changes of substrates and HRT did not change the dominant species. The archaeal community structures in methane reactors were similar both in single- and two- stage reactors, with acetoclastic methanogens Methanosarcina acetivorans-like organisms as the dominant species.
authors.affiliation: Department of Environmental Engineering, Technical University of Denmark, DK-2800 Kgs Lyngby, Denmark.
authors.forename: Gang
authors.initials: G
authors.lastname: Luo
authors.forename: Li
authors.initials: L
authors.lastname: Xie
authors.forename: Qi
authors.initials: Q
authors.lastname: Zhou
authors.forename: Irini
authors.initials: I
authors.lastname: Angelidaki
mesh_terms: D000693:Anaerobiosis; D001105:Archaea / Q000235:genetics; D001419:Bacteria / Q000235:genetics; D056804:Biofuels / Q000032:analysis*; D018533:Biomass; D019149:Bioreactors / Q000382:microbiology; D001709:Biotechnology / Q000379:methods*; D058645:Denaturing Gradient Gel Electrophoresis; D005232:Fatty Acids, Volatile / Q000032:analysis; D006859:Hydrogen / Q000032:analysis*; D006863:Hydrogen-Ion Concentration; D008697:Methane / Q000096:biosynthesis*; D009930:Organic Chemicals / Q000032:analysis*; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D012722:Sewage / Q000382:microbiology; D014866:Waste Products / Q000032:analysis*
chemical_list: D056804:Biofuels; D005232:Fatty Acids, Volatile; D009930:Organic Chemicals; D012336:RNA, Ribosomal, 16S; D012722:Sewage; D014866:Waste Products; D006859:Hydrogen; D008697:Methane