title: Economic analysis of microaerobic removal of H2S from biogas in full-scale sludge digesters.
abstract: The application of microaerobic conditions during sludge digestion has been proven to be an efficient method for H2S removal from biogas. In this study, three microaerobic treatments were considered as an alternative to the technique of biogas desulfurization applied (FeCl3 dosing to the digesters) in a WWTP comprising three full-scale anaerobic reactors treating sewage sludge, depending on the reactant: pure O2 from cryogenic tanks, concentrated O2 from PSA generators, and air. These alternatives were compared in terms of net present value (NPV) with a fourth scenario consisting in the utilization of iron-sponge-bed filter inoculated with thiobacteria. The analysis revealed that the most profitable alternative to FeCl3 addition was the injection of concentrated O2 (0.0019 €/m(3) biogas), and this scenario presented the highest robustness towards variations in the price of FeCl3, electricity, and in the H2S concentration.
authors.affiliation: Department of Chemical Engineering and Environmental Technology, Escuela de Ingenierías Industriales, Sede Dr. Mergelina, University of Valladolid, Dr. Mergelina s/n, 47011 Valladolid, Spain. Electronic address: israel.diaz@iq.uva.es.
authors.forename: I
authors.initials: I
authors.lastname: Díaz
authors.affiliation: Department of Chemical Engineering and Environmental Technology, Escuela de Ingenierías Industriales, Sede Dr. Mergelina, University of Valladolid, Dr. Mergelina s/n, 47011 Valladolid, Spain. Electronic address: irisrc@iq.uva.es.
authors.forename: I
authors.initials: I
authors.lastname: Ramos
authors.affiliation: Department of Chemical Engineering and Environmental Technology, Escuela de Ingenierías Industriales, Sede Dr. Mergelina, University of Valladolid, Dr. Mergelina s/n, 47011 Valladolid, Spain. Electronic address: maria@iq.uva.es.
authors.forename: M
authors.initials: M
authors.lastname: Fdz-Polanco
mesh_terms: D000332:Aerobiosis / Q000502:physiology*; D000693:Anaerobiosis; D056804:Biofuels / Q000382:microbiology*; D019149:Bioreactors / Q000382:microbiology*; D006862:Hydrogen Sulfide / Q000378:metabolism*; D010100:Oxygen / Q000378:metabolism; D012722:Sewage / Q000382:microbiology*
chemical_list: D056804:Biofuels; D012722:Sewage; D010100:Oxygen; D006862:Hydrogen Sulfide
keywords: Biogas; Economic analysis; FeCl(3); H(2)S removal; Microaerobic