title: Technical, Economical, and Microbiological Aspects of the Microaerobic Process on H2S Removal for Low Sulfate Concentration Wastewaters.
abstract: We studied the feasibility of the microaerobic process, in comparison with the traditional chemical absorption process (NaOH), on H2S removal in order to improve the biogas quality. The experiment consisted of two systems: R1, biogas from an anaerobic reactor was washed in a NaOH solution, and R2, headspace microaeration with atmospheric air in a former anaerobic reactor. The microaeration used for low sulfate concentration wastewater did not affect the anaerobic digestion, but even increased system stability. Methane production in the R2 was 14 % lower compared to R1, due to biogas dilution by the atmospheric air used. The presence of oxygen in the biogas reveals that not all the oxygen was consumed for sulfide oxidation in the liquid phase indicating mass transfer limitations. The reactor was able to rapidly recover its capacity on H2S removal after an operational failure. Bacterial and archaeal richness shifted due to changes in operational parameters, which match with the system functioning. Finally, the microaerobic system seems to be more advantageous for both technical and economical reasons, in which the payback of microaerobic process for H2S removal was 4.7 months.
authors.affiliation: Department of Hydraulic and Environmental Engineering, Federal University of Ceará, Rua do Contorno, S/N Campus do Pici, Bloco 713, Fortaleza, CE, CEP: 60455-900, Brazil.
authors.forename: M R
authors.initials: MR
authors.lastname: Sousa
authors.affiliation: Department of Hydraulic and Environmental Engineering, Federal University of Ceará, Rua do Contorno, S/N Campus do Pici, Bloco 713, Fortaleza, CE, CEP: 60455-900, Brazil.
authors.forename: C J S
authors.initials: CJ
authors.lastname: Oliveira
authors.affiliation: Department of Hydraulic and Environmental Engineering, Federal University of Ceará, Rua do Contorno, S/N Campus do Pici, Bloco 713, Fortaleza, CE, CEP: 60455-900, Brazil.
authors.forename: A C
authors.initials: AC
authors.lastname: Lopes
authors.affiliation: Department of Hydraulic and Environmental Engineering, Federal University of Ceará, Rua do Contorno, S/N Campus do Pici, Bloco 713, Fortaleza, CE, CEP: 60455-900, Brazil.
authors.forename: E R
authors.initials: ER
authors.lastname: Rodríguez
authors.affiliation: Department of Hydraulic and Environmental Engineering, Federal University of Ceará, Rua do Contorno, S/N Campus do Pici, Bloco 713, Fortaleza, CE, CEP: 60455-900, Brazil.
authors.forename: G B M
authors.initials: GB
authors.lastname: Holanda
authors.affiliation: Department of Hydraulic and Environmental Engineering, Federal University of Ceará, Rua do Contorno, S/N Campus do Pici, Bloco 713, Fortaleza, CE, CEP: 60455-900, Brazil.
authors.forename: P G C
authors.initials: PG
authors.lastname: Landim
authors.affiliation: Department of Hydraulic and Environmental Engineering, Federal University of Ceará, Rua do Contorno, S/N Campus do Pici, Bloco 713, Fortaleza, CE, CEP: 60455-900, Brazil.
authors.forename: P I M
authors.initials: PI
authors.lastname: Firmino
authors.affiliation: Department of Hydraulic and Environmental Engineering, Federal University of Ceará, Rua do Contorno, S/N Campus do Pici, Bloco 713, Fortaleza, CE, CEP: 60455-900, Brazil. andre23@ufc.br.
authors.forename: A B
authors.initials: AB
authors.lastname: Dos Santos
mesh_terms: D000332:Aerobiosis; D000693:Anaerobiosis; D001105:Archaea / Q000235:genetics / Q000378:metabolism*; D001419:Bacteria / Q000235:genetics / Q000378:metabolism*; D001673:Biodegradation, Environmental; D019149:Bioreactors / Q000382:microbiology; D002849:Chromatography, Gas; D058645:Denaturing Gradient Gel Electrophoresis; D052918:Environmental Restoration and Remediation / Q000191:economics* / Q000379:methods*; D006862:Hydrogen Sulfide / Q000302:isolation & purification*; D008697:Methane / Q000096:biosynthesis; D010100:Oxygen / Q000032:analysis; D010101:Oxygen Consumption; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D013431:Sulfates / Q000737:chemistry*; D062065:Wastewater / Q000737:chemistry* / Q000382:microbiology
chemical_list: D006862:Hydrogen Sulfide; D008697:Methane; D010100:Oxygen; D012336:RNA, Ribosomal, 16S; D013431:Sulfates; D062065:Wastewater
keywords: Anaerobic; Biogas desulfurization; DGGE; Hydrogen sulfide; Microaerobic process