Gasification of biomass in a circulating fluidized bed based calcium looping gasifier for hydrogen-enriched gas production: experimental studies

This paper presents experimental studies of circulating fluidized bed based calcium looping gasification (CFB-CLG) system for producing hydrogen-enriched gas from biomass. The merit of this system is that it captures carbon dioxide (CO2) during the process using the inexpensive and easily available sorbent calcium oxide (CaO). The process also regenerates the sorbent internally and produces a relatively pure stream of CO2. A laboratory scale calcium looping gasification system based on a circulating fluidized bed was developed and tested. Experiments conducted to gasify sawdust in the CFB-CLG system shows that it could produce a gas with 81% hydrogen and CO2 as low as 5%. Exergy analysis of the calcium looping system is done and the efficiency is 78.77%.