An Advanced Power-Generation System With CO2 Recovery Integrating Dimethyl Ether (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 of 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. Additionally, experiments on DME-fueled Chemical-looping combustion are carried out to verify the feasibility of the core process. 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.