Patent GB-746240-A (GB)
Title: Improvements relating to gas producing apparatus
IPC: C21D1/76
Filed: 1954-03-09
Abstract: 746,240. Gasifying gaseous hydrocarbons; purifying gases. GENERAL ELECTRIC CO. March 9, 1954 [March 9, 1953], No. 6861/54. Class 55(2). Apparatus for producing a carbon di-oxide free gas comprises a combustion chamber in which a gaseous hydrocarbon fuel is partially or completely combusted in air, a gas purifier containing hydrated iron oxide and a gas scrubber containing an aqueous solution of monoethanolamine, the gases from the combustion chamber passing first through the purifier and then through the scrubber. The iron oxide may be in a colloidal state and be made alkaline by the addition of lime and may be prepared from the iron-bearing material left after alumina has been extracted from bauxite ores by alkalies. The iron oxide is mixed with a filler material such as wood shavings, corn cobs or blast furnace slag. The solution of monoethanolamine may be a 12-15 per cent solution. In the Figure a mixture of hydrocarbon fuel and air is admitted at 5 to a combustion chamber 2 which is associated with a boiler 60 for regenerating washing liquid from the carbon di-oxide scrubber. The gases from the chamber 2 pass through a pipe 6, a heat exchanger 7, a cooler 9 and a water separator 11 to a purifier 1 containing colloidal alkalised ferric hydrate supported on wood shavings. The gas leaves the purifier 1 by line 14 and enters by lines 16 and 17 a scrubber 3 which contains a suitable packing over which a solution of monoethanolamine is distributed. Gas freed from carbon di-oxide leaves the top of the scrubber and passes into a cooler 22, a water separator 23 and thence by line 25 to be dried in any suitable drying apparatus. The water separated in separator 23, and which may contain traces of monoethanolamine is returned by a pipe 24 to the base of the scrubber 3. Liquid from the scrubber 3 is withdrawn through line 26, pump 27, heat exchanger 28, line 29 and passes into a packed tower 30 which is situated above and is in communication with the boiler 60. In descending the tower 30 and by heating in the boiler 60 the carbon di-oxide is driven off from the washing liquid, the liberated gases being passed into a cooler 32, a liquid separator 33 and through a vent 34 to atmosphere. Liquid from separator 33 is returned to the scrubber 3 by line 35<SP>1</SP>. Regenerated washing liquid is withdrawn from boiler 60 through line 35 by pump 36 and.passes in turn through heat exchanger 28, a cooler 39 and line 20 into the scrubber 3. A flow meter 70 is provided in line 20 and the flow of washing liquid through line 20 may be controlled by a check valve 69 according to the loading off the apparatus. Liquid make up may be added through the connection 74. A by-pass 78 with a valve 77 is provided for the purifier 1 and the purifier may be isolated from the gas stream by opening valve 77 and closing valves 13 and 15. When isolated the purifying material may be revivified by opening valve 81 and blowing in compressed air through line 79 and valve 80. Fuel gas and air are supplied through flow meters 41 and 45 respectively to a mixer 43 which also comprises a gas governor for equalizing the gas and air pressures ; the mixture passes to a compressor 47 and by line 48 to the inlet 5 to the combustion chamber 2. A lighting torch 54 flexibly connected to a valved connection 56 is supplied with the gas-air mixture through line 57. The gas-air mixture is ignited in the combustion chamber by inserting the torch through the valve 58. The temperature in the chamber 2 can be observed through a valve 59 and thermometers 71, 72 and 73 enable the temperature of both the gas and washing liquid to be controlled by suitable control of the air to fuel gas ratio a gas containing varying percentages of hydrogen, carbon-monoxide and nitrogen may be obtained and at 100 per cent aeration the hydrogen and carbon monoxide content is reduced to zero. Specification 462,439 is referred to.