Comparative evaluation of the performance of coal combustion in 0.5 and 50 kWth Chemical Looping Combustion units with ilmenite, redmud or iron ore as oxygen carrier.

13 figures, 2 tables.-- Work presented at the 13th International Conference on Greenhouse Gas Control Technologies, GHGT-13, 14-18 November 2016, Lausanne, SwitzerlandChemical Looping Combustion (CLC) is one of the most promising technologies to achieve the CO2 capture at a low economic and energetic penalty. In CLC the combustion is split in two steps: fuel combustion assisted by an oxygen carrier in the fuel reactor, and oxygen carrier regeneration in the air reactor by oxygen in air. Usually, the air and fuel reactors are interconnected fluidized beds, with the oxygen carrier circulating between them. Thus, the CO2 capture is inherent to the CLC process. The use of solid fuels in CLC is attracting great attention due to coal is the most abundant fuel, and burning biomass with CO2 capture would allow to reduce the atmospheric CO2 concentration. The in situ Gasification CLC (iG-CLC) allows the conversion of the solid fuel by performing both gasification and combustion of gasification products in the fuel reactor. In iG-CLC complete combustion is not reached, and an oxygen polishing step is required downstream by using a small fraction of pure oxygen.The authors thank the Spanish Ministry of Economy and Competitiveness (MINECO) for the funding received from the ENE2013-45454-R and ENE 2014-56857-R projects, as well as the European Regional Development Fund (ERDF).Peer reviewe