Sorbent enhanced water gas shift-rethinking carbon capture in IGCC

摘要

A dry sorbent pre-combustion CO2 capture process to reduce carbon emissions and enhance the water gas shift (WGS) reaction in integrated gasification combined cycle (IGCC) power plants was investigated. The approach aims to eliminate the need for WGS reactors by maximizing the amount of H2 through the removal of CO2 and resulting changes in syngas chemical equilibrium. This concept can limit the energy penalty typically required of a WGS reactor by maintaining the higher temperature and pressure conditions present at a coal gasifier outlet and desired at the gas turbine. The sorbent needed for this process must have high reactive surface area, high CO2 capacity, be able to tolerate required operating conditions (as high as 1000°C and 40 bar), and must have a long lifetime. A first principles approach was taken (thermodynamic and molecular modelling) to develop a list of candidate sorbents. Different approaches were taken to synthesize sorbents, including ultrasonic spray pyrolysis (USP), which led to materials with novel properties.