Novel combustion cycles incorporating capture of CO₂ with CaO

This paper presents a new approach for CO₂ capture from high temperature combustion gases that makes use of the reversible carbonation reaction of CaO and the calcination of CaCO3. Combustor and calciner are arranged to allow heat transfer from the combustor to the calciner in order to sustain the calcination (regeneration) reaction. Some examples of application of this concept are discussed for coal combustion systems. The sorbent performance issue is reviewed and integrated in the sorption/regeneration mass balances of the cycle. It is shown that a modest supply of fresh limestone, comparable to the use for sulphur control purposes, is enough to compensate for the intrinsic decay in sorbent activity. The work plan under a EU-funded project to further pursue this concept is outlined.