In this work, the Aspen Hysys conceptual design of a new process for energy generation at large scale with implicit CO
2 capture is presented. This process makes use of the CaO capability for CO
2 capture at high temperature and the possibility of regenerating this sorbent working in interconnected fluidised bed reactors operating at different temperatures. The proposed process has the advantage of producing power with minimum CO
2 emissions and very low energy penalties compared with similar air-based combustion power plants. In this system, five main parts can be distinguished: the combustor where coal is burnt with air, the calciner where the fresh and the recycled CaCO
3 is calcined, the carbonator where the CO
2 produced in the combustor is captured, the supercritical steam cycle and the CO
2 compression system. In this arrangement, the three fluidised bed reactors are interconnected in such a way that it is possible to perform the CaCO
3 calcination at a temperature of 950 °C with the energy transported by a hot solid stream produced in the circulating fluidised bed combustor operating at 1030 °C. The stream rich in CaO produced in the calciner is split into three parts. One of them is transported to the carbonator operating at 650 °C where most of the CO
2 in the flue gas produced in the combustor is captured. The second one is sent to the combustor, where it is heated up and used as energy carrier. The third solid stream that leaves the calciner is a purge in order to maintain the capture system activity and to avoid inert material accumulation. Because of the high temperatures involved in all the system, it is possible to recover most of the energy in the fuel and to produce power in a supercritical steam cycle. A case study is presented and it is demonstrated that under these operating conditions, 90% CO
2 capture efficiency can be achieved with no energy penalty further than the one originated in the CO
2 compression system.
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