Patent ID: 7883682

Claim:
A non-catalytic two-stage process for gasification of a carbonaceous material, which process comprises the steps of: (a) combusting in a first reaction zone a stream comprising an oxygen-containing gas and a first feedstock comprising of a slurry of particulate carbonaceous material in a liquid carrier at a temperature of between 2400° F. (1316° C.) and 3000° F. (1649° C.) and at a pressure of from 50 psig (345 kPa gage) to 600 psig (4137 kPa gage), thereby evolving heat and forming a first reaction product comprising liquid, molten slag and a gaseous products stream and entrained byproduct sticky, molten slag particles; (b) separating out and removing said liquid and molten slag; (c) combusting, in a second reaction zone a stream comprising an oxygen-containing gas, and a second feedstock comprising that portion of said first reaction product which comprises said gaseous products stream and said entrained byproduct sticky, molten slag particles and a second increment of a slurry of particulate carbonaceous material in a liquid carrier, at a temperature of between 2400° F. (1316° C.) and 3000° F. (1649° C.) and at a pressure of from 50 psig (345 kPa gage) to 600 psig (4137 kPa gage), thereby evolving heat and forming a second reaction product comprising liquid, molten slag and a gaseous products stream and entrained byproduct sticky, molten slag particles, and a stream of predominately carbon dioxide; (d) recovering a second portion of the heat from said gaseous products stream of the second reaction product in a high temperature heat recovery system, including a fire-tube boiler, whereby the gaseous products are cooled to a temperature of about 450° F. to about 550° F. (232° C. to 288.7° C.); and (e) recovering said stream of predominately carbon dioxide.