Membrane-integrated oxy-fuel combustion of coal: Process design and simulation

A membrane-integrated oxy-fuel combustion process is designed and simulated in UniSim Design®. The results of the simulation indicate that a net efficiency of 31.8% is obtained for a coal-fired power plant of 182 MWth (assuming only carbon in the coal), including the compression of CO2 to 100 bar. The specific electrical energy demand for CO2 capture in this process, including oxygen production and CO2 compression is ~0.58 MJ/kg. The required membrane area for air separation is ~80,000 m2 based on Ta-doped SrCo0.8Fe0.2O3-δ (SCF) membranes. By using the same protocol, the net efficiency is lower for an oxy-fuel combustion process using oxygen from cryogenic distillation of air (29.6%).