An Advanced Power-Generation System With $CO2$ Recovery Integrating DME Fueled Chemical-Looping Combustion

Dimethyl ether (DME) is a promising alternative fuel, but direct combustion of DME will result in extra energy penalty for $CO2$ separation. In this paper, an advanced power-generation system with $CO2$ recovery integrating DME fueled chemical-looping combustion is proposed. In the reduction reactor, DME is oxidized by $Fe2O3$ into $CO2$ and $H2O$⁠, and $Fe2O3$ is reduced into FeO simultaneously. Since the endothermic reduction in $Fe2O3$ with DME requires relatively low-grade thermal energy around $180°C$⁠, waste heat is used to provide the reaction heat. FeO is oxidized into $Fe2O3$ by air in the oxidation reactor, producing high-temperature flue gas to generate electricity through a thermal cycle. The gas production from the fuel reactor only consists of $CO2$ and $H2O$⁠, so $CO2$ can be easily separated through condensing with no extra energy penalty. As a result, the thermal efficiency could be expected to be 58.6% at a turbine inlet temperature of $1288°C$⁠. This proposed system may provide a new approach for high efficient use of DME in the industrial fields, and offer a possibility of chemical-looping combustion with inherent $CO2$ capture for the alternative fuel.