| abstract |
A process is described for the separation of an off-gas from a synthetic fuels production process, such as oil shale retorting, coal gasification, oxygen fireflooding or carbon dioxide miscible flood enhanced oil recovery, into an essentially sulfur-free, light fuel gas and a sulfur containing carbon dioxide gas. The off-gas is contacted with methanol to remove the sulfur containing gases and is then cooled to separate out a light fuel gas from a predominantly carbon dioxide gas. The carbon dioxide gas is again contacted with the same methanol to scrub the latter of sulfur-containing gas and reabsorb the sulfur onto the carbon dioxide gas. The carbon dioxide gas can then be recycled to the synthetic fuels production process with deposition of the sulfur therein or the gas can be delivered for export with downstream sulfur treatment. |