Investigation on the Trace Amount of Released CO in Sorption Enhanced Water Gas Shift Reaction Applied in Pre-combustion CO2 Capture and High Purity H2 Production

Abstract

Sorption enhanced water gas shift (SEWGS) is a developing technology that combines the water gas shift reaction and pre-combustion CO2 capture. It has the ability to in-situ remove CO2 and produce fuel cell level of hydrogen from coal derived syngas. In this paper, the trace amount of CO and CO2 leakage in SEWGS was analyzed. A SEWGS model was built by coupling the elementary kinetic CO2 adsorption model and the high temperature WGS model. It considered comprehensive coupling effects from mass and momentum transport processes, integrated with dynamic boundary condition and realistic operating procedures. 17 cases with different S/G ratio, feed flow, inlet CO concentration and balanced gas were simulated. The results indicated that the outlet CO concentration in SEWGS could be controlled below 50 ppm, even 10 ppm from the original 1000–30000 ppm of WGS thermodynamic balance concentration.