Patent GB-728439-A (GB)
IPC: C01B3/22
Abstract: <PICT:0728439/III/1> In a process for producing fuel gas of low calorific value and high hydrogen and carbon monoxide content from liquid or gaseous hydrocarbons, e.g. propone, butane, natural gas and petroleum oils, there is formed a gaseous mixture of a liquid gaseous hydrocarbon, steam and air which is continuously subjected to radiant heat in a series of stages, the last of which is at a temperature above 2000 DEG  F., wherein the volume and temperature of the gaseous mixture are increased and in the final heating stage the gaseous mixture is contacted with a catalyst, e.g. nickel oxide.  The process is carried out in an apparatus comprising a series of concentric cylinders and after leaving the stage in which the gaseous mixture contacts the catalyst the hot gases may be used to reduce an ore, e.g. iron ore.  As shown in Fig. 2 a mixture of the hydrocarbon, steam and air is led between concentric cylinders 20, 21 and 22, preferably made of nickel steel, and through an annular mass of catalyst 25, the resulting gases leaving by a tube 19 centrally disposed within the cylinder 20 and through wash box 27.  The catalyst 25 is contained between walls 23 and 24 of highly refractory material such as silicon carbide, the outer wall 24 being heated by combustion of a fuel gas in the space between the wall 24 and the outer wall 41 of the apparatus.  If the apparatus is to be used to reduce an ore, the ore may be accommodated in an additional section or it may be placed between the walls 23 and 24 and the catalyst may be placed between wall 23 and the cylinder 22.  The reactant mixture is admitted to the tube 20 through a mixing device 61a in which it is subjected to ultra-sonic vibrations (see Group II), a mixing chamber 18 and nozzles 63 to pass through the zones of increasing temperature formed between the cylinders 19, 20, 21, 22 and the walls 23 and 24. The cylinder 22 has a temperature of about 1700 DEG  F. and the wall 24 about 2200 DEG  F. Gases may be withdrawn separately from the various zones to give a gas of any desired calorific value.  The central tube 19, cylinder 21 and the wall 23 are secured to or built up to a cover plate 53 having a refractory cover 52, while the cylinders 20 and 22 rest on a base plate 46 which is supported by the mixing chamber 18 and wash box 27.  The wall 24 is built up to a flanged top plate 47, a flexible metallic bellows connection between the plate 47 and the wall 41 allows relative movement of the parts of the apparatus due to expansion.  Walls 23 and 24 are supported by removable members 45 and 43 so that the walls can be repaired if necessary.  Catalyst is fed to the space between the walls 23 and 24 through a plug-hole 55 and is supported by a removable member 57 so that the catalyst can be changed or alternatively if ore is placed in this section so that the metal can be removed after the ore has been reduced.  When a liquid hydrocarbon feed is employed it may be subjected to a preliminary distillation, the lighter fractions being fed to the generator while the heavier fractions are used to heat the generator.  Catalyst poisoning materials may be removed from the vapours during this distillation.  The mixture of hydrocarbon, steam and air may be preheated before entering the mixing device 61a in a preheater 12 arranged in the space between the cover plate 53 and the top plate 47.