Potential of high-temperature steam reforming for enabling DME as a hydrogen carrier

In order to facilitate the importation of renewable hydrogen to Europe via dimethyl ether (DME), it is imperative to develop a robust steam reforming technology that is currently not available. This study explores the potential of state-of-the-art steam reforming technology of natural gas processing to address this technology gap, thereby facilitating accelerated commercialization. A process simulation was conducted in which a steam methane reformer (SMR) and a steam DME reformer with an integrated carbon capture unit (capture rate: 90 %) were modeled and compared in terms of efficiency, CO 2 emissions, feedstock consumption, hydrogen yield and energy demand. The steam DME reformer demonstrated a cold gas efficiency (CGE) of 70.9 %, accompanied by uncaptured carbon emissions (UCE) of 1.12 kg CO₂ per kg H₂, as compared to 73.0 % efficiency and 1.03 kg CO₂ per kg H₂ observed for the SMR. The performance of the amine scrubber had the most significant impact on both the CGE and the UCE. Although DME reforming exhibited slightly lower efficiency and higher feedstock and energy requirements, it consistently achieved higher hydrogen yields, underscoring its potential as a renewable hydrogen carrier. This work should therefore be regarded as a foundational baseline study, providing the first detailed reference point for renewable DME reforming and a basis for future research into optimized reforming conditions, advanced concepts, and alternative CO₂ capture strategies. • Adaption of an SMR with carbon capture to DME for the DME/CO₂ cycle • Evaluation of thermodynamics of high-temperature DME steam reforming • Comparison of DME and methane reforming by CO₂ emission and efficiency metrics • Finding of similar performance, mainly affected by amine scrubber efficiency