Catalyst Development and Distributed Electrified Heating in Reforming Processes for Efficient Renewable Syngas and Fuel Production

Abstract

Efforts to mitigate climate change primarily focus on reducing globalgreenhouse gas emissions, particularly carbon dioxide (CO₂). Without intervention,global warming could lead to a 3.2 ^◦C temperature increase, resultingin an 18 % global GDP loss. Achieving the Paris Agreement’s goal oflimiting temperature rise to 1.5 ^◦C (which if surpassed could lead to extreme climate change) requires significant cuts in GHG emissions, as outlined by theIPCC’s recommendation to decrease CO₂ emissions by 45 % from 2010 levels by 2030, reaching net-zero by 2050. Biomass, with its potential for carbon neutrality or negativity, is a vital renewable feedstock, convertible into greenfuels via thermochemical processes like gasification, pyrolysis, and anaerobic digestion. However, these processes face challenges, such as catalyst deactivationand high energy demands. Additive manufacturing and electrification are emerging solutions, offering enhanced catalyst stability and increased energy efficiency by reducing reliance on fuel combustion. This doctoral thesis focuses on an extensive overview of the state-of-theart of renewable feedstocks with a focus on its challenges and perspective, as well as investigative work based on these findings. The latter opened the pathfor the design, fabrication, electrification and testing of such 3D-printed catalysisin the catalytic reforming of renewable feedstocks. The experimental workwas aided by CFD simulations, and proofs-of-concept were developed using process simulation software and techno-economic analysis. The experimental results show a successful demonstration of the electrified catalytic reforming technology of biomass pyrolysis volatiles for syngas production, resulting incomplete bio-oil reforming to syngas, with a highest yield of 0.071 g H₂ g⁻¹ biomass with excellent catalyst stability and energy efficiency of 66 %. The CFD results show how the lattice structure of the 3D-printed catalyst resultsin a higher surface area and improved transport phenomena, which resultin enhanced mass and heat transfer properties. Furthermore, this novel 3D printed catalyst was tested for catalytic dry reforming of synthetic biogas using induction as heat source, resulting in complete reforming to syngas with minimal coke deposition, compared to commercially available catalysts, highlighting the effect of the catalyst’s geometry on its stability. Based on the electrified catalytic reforming technology, process designand development at an industrial scale were investigated to achieve integration with product upgrading (such as synthetic natural gas, i.e. SNG, and H₂ production). The developed processes were compared with non-electrified reforming technologies using mass and energy balances, as well as using techno-economic analyses, sensitivity analyses, and CO₂-equivalent analyses. Regarding SNG production, the results show a production cost of 18 SEK kg⁻¹ SNG, toward a selling price of 27 SEK kg⁻¹ SNG, resulting in an economic profit: capital investment recovery (break-even point) within two years of operation and a net cash flow of 5,000 MSEK after 20 years. In terms of process parameters the results show susceptibility to high steam-to-biomassratios and the market price of both biomass and biochar. Regarding H₂ production,electrified catalytic reforming technology results in 93 % reduction of the CO₂-equivalents compared to industrial natural gas reforming.

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