Electrification of gasification-based biomass-to-X processes - a critical review and in-depth assessment

To address the impacts of climate change, it is imperative to significantly decrease anthropogenic greenhouse gas emissions. Biomass-based chemicals and fuels will play a crucial role in substituting fossil-based feedstocks and reducing emissions. Gasification-based biomass conversion processes with catalytic synthesis producing chemicals and fuels (Biomass-to-X, BtX) are an innovative and well-proven process route. Since biomass is a scarce resource, its efficient utilization by maximizing product yield is key. In this review, the electrification of BtX processes is presented and discussed as a technological option to enhance chemical and fuel production from biomass. Electrified processes show many advantages compared to BtX and electricity-based processes (Power-to-X, PtX). Electrification options are classified into direct and indirect processes. While indirect electrification comprises mostly the addition of H₂ from water electrolysis (Power-and-Biomass-to-X, PBtX), direct electrification refers to power integration into specific processing steps by converting electricity into the required form of energy such as heat, electrochemical energy or plasma used (eBtX). After the in-depth review of state-of-the-art technologies, all technologies are discussed in terms of process performance, maturity, feasibility, plant location, land requirement, and dynamic operation. H₂ addition in PBtX processes has been widely investigated in the literature with process simulations showing significantly increased carbon efficiency and product yield. Similar studies on direct electrification (eBtX) are limited in the literature due to low technological maturity. Further research is required on both, equipment level technology development, as well as process and system level, to compare process options and evaluate performance, economics, environmental impact and future legislation.