DIRECT CHEMICAL LOOPING FOR HYDROGEN PRODUCTION USING COAL WITH IRON OXIDES – BASED OXYGEN CARRIER

Abstract

The present work entitled as “Direct Chemical Looping for Hydrogen production using coal with iron oxide-based oxygen carrier” is related to the modeling of the Coal direct chemical looping (CDCL) and Syngas chemical looping (SCL) processes as described Gnanapragasam et. al (2009). The models take in to consideration twenty-two reactions (coal-Devolatilization, char gasification, oxygen carrier reductions and oxidations, char combustion) taking place inside various reactors involved in the processes. The results are verified with the published results. Further, the verified model is used to study the suitability of Indian coal for coal direct chemical looping process. The simulation results shows that the Hydrogen production is maximum at the lower oxygen input flowrate to main reactors (Fuel reactor in CDCL and Gasifier in SCL). Also, the Hydrogen production is higher in CDCL than the SCL process, unlike, the Carbon dioxide emission which is constant and same for both the processes. This observation concludes that the both the processes are capable of about 100% carbon capture. The effect of Coal carrier gas was found to be negligible at the set operating conditions. In case of temperature effect analysis, the hydrogen production increases with Temperature increment till the temperature of 5800C after which the effect of temperature found to be negligible.