CO2 capture from syngas using solid CO2 sorbent and WGS catalyst

Abstract

Abstract IGCC integrated with CCS has been regarded as a promising option to reduce CO 2 emission under the situation that coal is the dominant source among fossil fuels for the electricity-generation. Recently, KEPCO Research Institute proposed the new concept for the pre-combustion CO 2 capture process, which is named as one loop sorption enhanced water gas shift (SEWGS) process consisted of two fluidized bed reactors. Sorption enhanced water gas shift (SEWGS) process is combined with the water-gas shift reaction with CO 2 capture at the same time. In this study, Five MgO-based dry regenerable CO 2 sorbents and Five CuO-based water gas shift catalysts were prepared by spray-drying technique to evaluate their applicability to a fluidized-bed SEWGS process. In these sorbents, MgO-based sorbents satisfied most of the physical requirements for commercial fluidized bed reactor process along with reasonable chemical reactivity. All sorbents had a spherical shape, an average size of 108–150 μm, and a size distribution of 42–250 μm, a bulk density of 0.60–1.16 g/mL. The attrition Index (AI) of all the sorbent was below 15%, compared to about 20% for commercial fluidized catalytic cracking (FCC) catalysts. CO 2 sorption capacity of Sorb A was approximately 17.6 wt% at 200 °C and 21 bar with synthesis gas conditions. Spray dried CuO-based WGS catalyst showed relatively good physical properties. Most of catalyst had a spherical shape, an average size of 120–160 um, and a size distribution of 42–250 μm, a bulk density of 0.92–1.06 g/mL. Attrition Indices (AI) of Cat D and Cat E was below 10%, which is suitable for fluidized SEWGS process. CO conversion of Cat E was over 90% at 350 °C with simulated synthesis gas conditions.