ARCENEGUI TROYA, JUAN JESÚS, Enrique Sanchez-Jimenez, Pedro , Perejon, Antonio , MORENO GARCÍA, VIRGINIA, Manuel Valverde, Jose , Allan Perez-Maqueda, Luis
No
Chem. Eng. J.
Article
Científica
16.744
2.419
01/08/2021
000653229500198
In the present work, we explore the use of steam in the CaCO3 calcination step of the Calcium Looping process devised for thermochemical energy storage (CaL-TCES). Steam produces a double benefit: firstly, it fastens calcination, allowing a reduction of the temperature needed to attain full calcination in short residence times, as those required in practice, resulting in energy savings. This behaviour is justified on the basis of a kinetics study results obtained from a non-parametric kinetic analysis, which demonstrate that the presence of steam during calcination can reduce the apparent activation energy from 175 kJ/mol to 142 kJ/mol with a steam's partial pressure of 29%. In addition, the results obtained for multicycle CaL-TCES tests show that steam alleviates the deactivation of the sorbent, which is one of the main limiting factors of this technology. This behaviour is explained in terms of the effect of steam on the microstructure of the regenerated CaO. Importantly, the values of residual conversion attained by calcining in steam are higher than those without steam.
Concentrated solar power; Limestone; Thermochemical energy storage; Calcium looping; Steam; Kinetics