NOVELTY - Converting a sulfur-containing carbonaceous fuel (1) into a combustible product gas, involves mixing the fuel with a first solution of an alkali metal carbonate (5) to form a slurry; pressurizing and feeding the slurry into a gasifier (9); feeding a pressurized oxygen-containing gas into gasifier to produce carbon monoxide and water vapor, and a hot liquid smelt containing molten alkali metal sulfide; dissolving smelt in aqueous medium to form second solution; and utilizing depressurized and regenerated second solution as the principal ingredient of the first solution.    USE - For converting a sulfur-containing carbonaceous fuel (e.g. petroleum coke) into a combustible product gas (claimed) containing hydrogen and carbon monoxide; and useful as fuel for gas turbine.    ADVANTAGE - The method converts the sulfur-containing carbonaceous fuel into the combustible product gas, which has a high heating value of at least 100 Btu/scf, dry basis. In the gasification process, a variety of carbonaceous materials can be handled, including anthracite, bituminous and lignite coals; and several types of petroleum coke, organic waste, photographic film, wood chips, and heavy residual hydrocarbons. The fuel particles are pneumatically injected into the melt and are immediately wetted and dispersed so there is no opportunity for caking or swelling to affect operation. In the process, the feed need not be closely sized; and pulverization and fines removal are unnecessary. The method only requires that solid feed the is pneumatically conveyable, which generally requires particles of less than 4 mesh. The product gas is essentially free of sulfur, and approximately 90-99% of feed sulfur is recovered in the regeneration system, and this level of removal is generally adequate to meet environmental requirements for combustion use of product gas. The method produces negligible amounts of tar, heavy hydrocarbons and nitrogen oxides (NOx). The catalytic effect of the melt apparently causes almost complete destruction of heavy hydrocarbons and organic nitrogen compounds at the gasifier operating temperature. The method requires relatively low amount of oxygen. The gasifier turndown capability is excellent because a gas-sparged molten pool is relatively insensitive to gas velocity. In the process, there is no explosion hazard, when the fuel feed stops, and any oxygen that flows into the molten salt pool is absorbed by an inventory of reduced compounds (sodium sulfide, residual carbon). The method has high thermal efficiency because no char is produced and carbon utilization is generally over 98%, and has low heat losses because the reaction zone is not actively cooled, and product gas is amenable to efficient heat recovery because of its moderate temperature and relative freedom from tar, ash and other objectionable impurities. The method easily recovers valuable byproducts such as sulfur and vanadium; and retains all ash constituents in the melt which is processed to return sodium carbonate to the gasifier.    DETAILED DESCRIPTION - Converting a sulfur-containing carbonaceous fuel (1) into a combustible product gas having a higher heating value of at least 100 Btu/scf, dry basis, by reaction with oxygen in the presence of a molten alkali metal salt, involves mixing particles of the fuel with a first solution containing alkali metal carbonate (5) (5-35 wt.%), at atmospheric pressure, to form a slurry containing undissolved fuel particles (25-75 wt.%); pressurizing and feeding the slurry into a gasifier (9) operating at an elevated pressure of 4-50 atmospheres, where the gasifier contains a drying zone (10) and a gasification zone (11); feeding pressurized oxygen-containing gas into the gasifier; drying the slurry in a drying zone of the gasifier; gasifying the resulting dried mixture of fuel and salts by reacting with oxygen at 900-1400 degrees C, in a gasification zone of the gasifier, to produce a gasifier off-gas containing carbon monoxide and water vapor, and a hot liquid smelt containing molten alkali metal sulfide; draining the smelt into a quench tank operating at the same pressure as the gasifier; dissolving the resulting smelt in an aqueous medium, to form a second solution containing alkali metal salts (5-35 wt.%) including alkali metal sulfide; recovering the gasifier off-gas as the combustible product gas; reducing the pressure on the second solution, and regenerating the second solution by converting the alkali metal sulfide to alkali metal carbonate in the solution, and hydrogen sulfide gas that is released from solution; and utilizing the depressurized and regenerated second solution as the principal ingredient of the first solution. The pressure on the second solution is reduced by contacting the second solution with a carbon dioxide-containing gas to form alkali metal bi-sulfide and bicarbonate in solution, depressurizing the solution, and stripping hydrogen sulfide gas from it to produce a stream of hydrogen sulfide-rich gas and a stream of depressurized and regenerated second solution.    DESCRIPTION OF DRAWING(S) - The figure shows a flow diagram of the process for converting sulfur-containing carbonaceous fuel into a combustible product gas.    Sulfur-containing carbonaceous fuel (1)    Alkali metal carbonate (5)    Gasifier (9)    Drying zone (10)    Gasification zone. (11)