Electrification of sorption enhanced gasification: Introduction of a novel fluidized bed reactor system

An advanced multi-fluidized bed (MFB) reactor system for electrically assisted sorption enhanced gasification (E-SEG) of biomass is proposed, which enables improved biomass conversion and separation of a concentrated CO 2 stream via the integration of electricity as external heat source. Conventional SEG, realized by utilizing limestone as heat - and CO 2 carrier in a dual fluidized bed (DFB) reactor, is a promising process for the in-situ and simultaneous generation of a H 2 -enriched product gas suitable for synthesis and a separate CO 2 -enriched flue gas stream. The extension of the DFB system with two additional reactors enables char separation from carbonated sorbent as well as electrically driven high temperature char gasification (fixed carbon) and flameless calcination of CaCO 3 . Process simulation shows that cutting down on char combustion through direct electrification can lead to an increase of the specific product gas yield by up to 80% (1.58 Nm 3 db /kg daf ) and to a roughly 12% higher cold gas efficiency (0.79 MW LHV,PG /MW LHV,org+el ) compared to state-of-the-art SEG. The required electricity demand accounts to about 39% of the thermal fuel input. E-SEG and SEG are further compared in terms of carbon and exergy flow diagrams. Additionally, design considerations as well as technical requirements and challenges of such a reactor system are discussed and the impact of critical process parameters on key performance indicators is studied via a sensitivity analysis. • Fluidized bed reactor for electrified biomass gasification with CO 2 removal (SEG). • Process simulation compares electrified SEG to classical SEG. • Increase of product gas yield by up to 80% compared to classical SEG. • Sensitivity analysis shows impact of reactor functionalities.