Sorbent enhanced hydrogen production from steam gasification of coal integrated with CO2 capture

In this work, CO2 capture and H-2 production during the steam gasification of coal integrated with CO2 capture sorbent were investigated using a horizontal fixed bed reactor at atmospheric pressure. Four different temperatures (650, 675, 700, and 750 degrees C) and three sorbent-to-carbon ratios ([Ca]/[C] = 0, 1, 2) were studied. In the absence of sorbent, the maximum molar fraction of H-2 (64.6%) and conversion of coal (71.3%) were exhibited at the highest temperature (750 degrees C). The experimental results verified that the presence of sorbent in the steam gasification of coal enhanced the molar fraction of H-2 to more than 80%, with almost all CO2 was fixed into the sorbent structure, and carbon monoxide (CO) was converted to H-2 and CO2 through the water gas shift reaction. The steam gasification of coal integrated with CO2 capture largely depended on the reaction temperature and exhibited optimal conditions at 675 degrees C. The maximum molar fraction of H-2 (81.7%) and minimum CO2 concentration (almost 0%) were obtained at 675 degrees C and a sorbent-to-carbon ratio of 2. Copyright (c) 2014, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.