Climate neutral H2 production through non-catalytic methane pyrolysis : Using biomethane in a non-catalytic pyrolysis reactor

Sammanfattning

H2 is expected to play a key role in the transition to a climate neutral energy system, making climate neutral H2 production essential. This study evaluates the economic viability of methane pyrolysis as a fossil free pathway for H2 production. Methane pyrolysis is a thermochemical process in which methane is decomposed into H2 and solid carbon in the absence of oxygen. A model of a methane pyrolysis plant producing 5 tons of solid carbon per hour was developed in Aspen Plus and simulated at different reactor temperatures. The results show that a reactor temperature of 1500 °C provides the most favorable economic performance. At this temperature, the levelized cost of H2 (LCOH) was calculated as 7.55 €/kgH₂, while the levelized cost of carbon (LCOC) was 2.17 €/kgCB. Sensitivity analysis indicates that the economic performance is most strongly influenced by equipment cost and biogas price. When biomethane is used as feedstock, the process enables the production of solid carbon from biogenic carbon, resulting in the potential for negative carbon dioxide emissions. Although the electricity demand of methane pyrolysis can exceed that of electrolysis under certain operating conditions, the process shows significant potential for optimization and reduced electricity consumption. Overall, methane pyrolysis appears to be a promising carbon neutral H2 production pathway.