“…In the Ca-Cu looping process, the exothermic reduction of CuO to Cu using a gaseous fuel (e.g., CH 4 , CO, or H 2 ) supplies the necessary heat to carry out simultaneously the calcination of the carbonated sorbent producing exclusively CO 2 and H 2 O without the presence of an ASU in the process (Fernández et al, 2012). A substantial progress has been made during the EU ASCENT project on dynamic reactor modeling (Martini et al, 2016(Martini et al, , 2017Fernández and Abanades, 2017a), development of Ca-Cu materials (Kazi et al, 2017), process integration (Riva et al, 2018;Martínez et al, 2019b), and experimental validation from small reactors to packed beds at TRL5 (Fernández and Abanades, 2017b;Grasa et al, 2017;Díez-Martín et al, 2018;Martínez et al, 2019a). Some recent works have proposed the use of the Ca-Cu based process to convert the BFG into valuable products, such H 2 /N 2 and pure CO 2 , using a combination of several interconnected fluidized beds operating in continuous mode (Fernández et al, 2017;Martínez et al, 2018).…”