Sorbent steam reactivation and methane-concentrated calcination for calcium-looping carbon capture: Compatibilities and limitations.

• Process provides simultaneous sorbent reactivation and steam superheating. • Methane-concentrated oxyfuel calciner is assessed for CaCO 3 /Ca(OH) 2 co-calcination. • Conditions for autothermal, coke-free and complete sorbent regeneration are studied. This paper investigates the equilibrium performance of CaO hydration and CaCO 3 /Ca(OH) 2 co-calcination in calcium-looping processes. A novel lime hydration configuration is proposed, introducing saturated steam as the reactivating reagent and direct-heat-removal medium. The proposed hydrator generates a substantial amount of superheated steam, used elsewhere as required. The slaked lime and limestone are calcined simultaneously in a methane-concentrated oxy-fuel calciner. The equilibrium performance of the co-calciner is studied at different reactor temperatures, operating pressures, solid/gas feed ratios and feed compositions. A correlation is proposed which estimates the required gaseous feed composition for autothermal, coke-free and complete sorbent regeneration using this novel technology. [ABSTRACT FROM AUTHOR]