Production of sulfur-free carbon monoxide-containing gas

摘要

829,844. Gas manufacture. TEXACO DEVELOPMENT CORPORATION. Nov. 4, 1957, No. 34335/57. Classes 55 (1) and 55 (2). In a process for producing carbon monoxide containing gas substantially free from sulphurcontaining gases, a sulphur-containing solid carbonaceous fuel also containing ash is mixed with lime, in excess of that theoretically required for the removal of all the sulphur contained in the fuel, and reacted with a free oxygen containing gas in a reaction zone at a temperature above 2000‹ F. and also above the fusion point of the slag resulting from the lime and ash, the resulting molten slag is quenched with water in the presence of the carbon monoxide containing product gas to effect a solution of lime from the slag, the resulting limewater is stripped of hydrogen sulphide in the absence of the product gas and then contacted therewith to remove sulphur-containing gas therefrom. A slurry of coal, water and lime, which may be calcium oxide, hydroxide or carbonate, is prepared in a mixer 5 and passed by pumps 6 through a tubular heater 7 so as to form a dispersion of solid particles in steam. A cyclone separator 11 may discharge the steam through line 12. The coal and lime, together with steam, if desired, is fed, together with oxygen from line 9, into a mixer-burner in gas generator 8 which is maintained at a temperature of 2000‹ to 3000 ‹ F. and pressure between atmospheric and 2,000 pounds per square inch, preferably between 100-400 pounds per square inch. The product gas and molten slag passes through outlet 13 into a quench chamber 14 where water, admitted through line 41, maintains a liquid level 16. The product gas is withdrawn through line 17 to a gas scrubber 18, being quenched with recycled water introduced through line 42 and/or fresh water through line 43. The slag and limewater withdrawn from chamber 14 is freed from steam, hydrogen sulphide and other gases in flash tank 22, stripping steam being supplied at 23. The water and slag passes to a settler 26, from which water passes through line 28 to the top of scrubber 18, lime being added from hopper 29. The product gas is discharged at 31. Water from scrubber 18 is stripped of sulphur-containing gases in stripper 33 by means of steam or carbon dioxide fed in at line 36. In the case of carbon dioxide being used, calcium carbonate is formed, which is fed to settling tank 38, water being passed to lines 41, 42 or discarded at 44, and calcium carbonate slurry is fed to the mixer 5 through line 39.