“…One way of doing this is to introduce the coal directly to the fuel reactor where the gasification of the coal and subsequent reactions with the metal oxide particles will occur simultaneously (Lyon and Cole, 2000;Dennis et al, 2006;Scott et al, 2006;Gao et al, 2008;Leion et al, 2008b;Rubel et al, 2009). A few circulating CLC units operating with this principle have recently been erected (Andrus et al, 2005;Lyngfelt, 2008a, 2008b;Shen et al, 2009) and there is plenty of gasification literature for example (Wen and Lee, 1979;Weeda et al, 1993;Walker et al, 1959;Su and Perlmutter, 1985).…”