On the effect of biogas composition on the H2 production by sorption enhanced steam reforming (SESR)

• Main Authors: Capa Tamargo, Alma, García Fernández, Roberto, Chen, D., Rubiera González, Fernando, Pevida García, Covadonga, Gil Matellanes, María Victoria
• Other Authors: Ministerio de Ciencia e Innovación (España), Principado de Asturias
• Format: Article in Journal/Newspaper
• Language: English
• Published: Elsevier 2020
• Subjects: Biogas; CH4/CO2 composition; Hydrogen; Sorption enhanced steam reforming; Pd/Ni–Co catalyst; CO2 capture; Dolomite; Arctic; Norway
• Online Access: http://hdl.handle.net/10261/217175; https://doi.org/10.1016/j.renene.2020.06.122; https://doi.org/10.13039/501100004837; https://doi.org/10.13039/100011941

Biogas is a valuable source of renewable energy produced from biodegradable organic materials via anaerobic digestion. The production of H2 by sorption enhanced steam reforming (SESR) of biogas has been studied thermodynamic and experimentally. A Pd/Ni–Co catalyst and dolomite as CO2 sorbent were used. The effect of biogas composition (CH4/CO2 vol.%) on the process was evaluated at 600 and 650 °C in a fluidized bed reactor using biogas CO2 concentrations of 5–50 vol.%. During conventional biogas steam reforming (SR), high CH4 partial pressures in the feed favor the process, producing high H2 concentrations. During biogas SESR, CO2 was effectively removed from the gas phase by the sorbent for all the biogas compositions, and it did not alter the process compared to pure methane. Steam methane reforming (SMR) and water-gas shift (WGS), together with carbonation, were the main reactions occurring during biogas SESR. Dry (or CO2) methane reforming did not occur under the conditions studied due to the relatively low temperature and the presence of steam. High H2 purity (98.4 vol.%) and H2 yield (91%) were experimentally obtained, pointing out the biogas SESR as a promising technology for the efficient production of high-purity, high-yield hydrogen from a renewable source. The authors thank Franefoss Miljøkalk A/S (Norway) for supplying Arctic dolomite. This work was carried out with financial support from the Spanish MICINN (Project ENE2017-83530-R) and from the Gobierno del Principado de Asturias (PCTI, Ref. IDI/2018/000115), both co-financed by the European Regional Development Fund (ERDF). M.V. Gil acknowledges support from a Ramón y Cajal grant (RYC-2017-21937) of the Spanish government, co-financed by the European Social Fund (ESF). A. Capa acknowledges a fellowship awarded by the Spanish MICINN (FPI program, PRE2018-083634), co-financed by the European Social Fund (ESF). Peer reviewed