Patent ID: 7988752

Claim:
A process for producing a gas product from a carbonaceous fuel in a gasifier, the process comprising: oxidizing CaS in air within an oxidizer reactor to form hot CaSO 4 ; providing the hot CaSO 4 and a carbonaceous fuel to a reducer reactor wherein the hot CaSO 4 and the carbonaceous fuel undergo an endothermic reaction utilizing heat content of the hot CaSO 4 to form CaS and a gas product, whereby a sufficient amount of oxygen is supplied for substantially complete combustion of the carbonaceous fuel such that the gas product is substantially all CO 2 and steam; providing a gas flow from the reducer reactor to a separator. wherein he gas flow includes the gas product and entrained CaS; separating the gas product and entrained CaS of the gas flow; and providing the separated CaS to the oxidizer reactor for use in the oxidizing.