Biomass Chemical Looping Combustion Based on Fe-Based Oxygen Carriers to Capture Co2 Coupled with Chemical Looping Hydrogen Production to Produce Ammonia

Abstract

This work develops a process for CO2 capture by biomass chemical looping combustion coupled with chemical looping hydrogen production to ammonia using Aspen Plus software. By using pine wood biomass and water as feedstock and ammonia as end product, the influence of key parameters on the system performance is explored through a combination of process simulation and sensitivity analysis, and the optimal operating parameters are determined: OC/B=10, fuel reactor (FR) temperature is 850°C, S/B=4, hydrogen reactor (HR) temperature is 600°C, AIR/B=1.6 and NH3 reactor (NR) temperature and pressure are 300 °C and 150 bar, respectively. H2 yield of 7.21% and NH3 yield of 31.5% are obtained, and the H2 yield is increased by 37.3% relative to the biomass direct hydrogen production; the total exergy efficiency for the system is 89.3% at 95% CO2 capture efficiency, and the energy consumption is 58.78kw. In contrast, the exergy efficiency of conventional coal direct hydrogen production is 58% at 90% CO2 capture efficiency. The exergy efficiency of this system is improved by 53.9%.

Keywords: biomass chemical looping combustion, CO2 capture, Hydrogen, ammonia, exergy efficiency