Biogas upgrading through CO2 methanation in a polytropic - distributed feed fixed bed reactor

Durán, P. (Universidad de Zaragoza) ; Aragüés-Aldea, P. (Universidad de Zaragoza) ; González-Pizarro, R. (Universidad de Zaragoza) ; Mercader, V. D. (Universidad de Zaragoza) ; Cazaña, F. (Universidad de Zaragoza) ; Francés, E. (Universidad de Zaragoza) ; Peña, J. A. (Universidad de Zaragoza) ; Herguido, J. (Universidad de Zaragoza)

Resumen: Methanation of the CO2 contained in a biogas stream has been experimentally analyzed in a fixed bed reactor with a Ni-Mn catalyst, evaluating the effect of feeding reactants distributed throughout the bed. The performance of different feeding configurations (conventional cofeeding and others implying a lateral distribution of one of the reactive streams) has been analyzed for different nominal temperatures T (250–400 ºC) and weight-related space velocities WHSV (47.71–6.63 gCO2 gcat-1 h-1), always keeping a H2: CO2 ratio of 4:1, and a CH4:CO2 ratio of 7:3. For identical WHSV, the lateral biogas distribution (Poly-Biogas feeding configuration) always showed the best results in terms of activity (higher conversion at the same temperature) and selectivity (lower selectivity to CO in iso-conversion). These better results agree with what was observed in a previous work in methanation of CO2 (i.e., without methane in the feed). In that work, CO2 was distributed along the catalytic bed by several lateral feeds (Poly-CO2). When T was kept constant and WHSV was varied, the reactor fed with distributed biogas (Poly-Biogas), again confirmed its higher efficiency and better selectivity for biogas upgrading (i.e., higher CH4 content). Furthermore, by adopting a Poly-Biogas (or poly-CO2) feeding configuration, a more homogeneous temperature profile was achieved along the bed avoiding the severity of hot spots appearance. In contrast, the lateral distribution of hydrogen (Poly-H2) always led to similar or worse results than those for the conventional co-feeding configuration.

Idioma: Inglés

DOI: 10.1016/j.cattod.2024.114849

Año: 2024

Publicado en: Catalysis Today 440 (2024), 114849 [9 pp.]
ISSN: 0920-5861

Financiación: info:eu-repo/grantAgreement/ES/AEI/PID2022-136947OB-I00
Financiación: info:eu-repo/grantAgreement/ES/DGA/T43-23R
Financiación: info:eu-repo/grantAgreement/ES/MICINN/PID2019-104866RB-I00
Financiación: info:eu-repo/grantAgreement/ES/MICINN/PID2020-113809RB-C31/AEI/10.13039/501100011033
Financiación: info:eu-repo/grantAgreement/ES/MICINN/PRE2020-095679

Tipo y forma: Article (Published version)

Área (Departamento): Área Ingeniería Química (Dpto. Ing.Quím.Tecnol.Med.Amb.)
Área (Departamento): Área Química Física (Dpto. Química Física)