Process and Reactor Level Simulations of Coal-Direct Chemical-looping Combustion

Abstract

Reducing carbon emissions from fossil-fueled power plants has been an active area of research in recent years. One technology that appears to be very promising for high-efficiency low-cost carbon capture is chemical-looping combustion (CLC) . CLC involves combustion offuels (either gas or solid) by heterogeneous chemical reactions with an oxygen carrier, usually a particulate metal oxide. Because of the absence of air in the fuel reactor, the combustion products are not diluted by other gases (e.g., N 2 ), resulting in high purity of CO 2 available at the fuel reactor outlet. Also, the net energy release from a CLC process is theoretically identical to that from conventional combustion of the fuel (2001) has shown that the energy cost of solid circulation, which is the only energy cost of separation, is a very small percentage (approximately 0.3 %) of the total energy released by the combustion process compared to other pre-combustion technologies such as the oxy-fuel combustion in which the oxygen separation process consumes nearly 15 % of the electricity generation (Hong et al. 2009a, b). Therefore, CLC holds significant promise as a next-generation combustion technology due to its potential to allow zero CO 2 emission with little effect on the efficiency of the power plant.