Patent GB-619761-A (GB)
Title: Improved apparatus for carrying out gaseous reactions at high temperatures
IPC: B01J8/18
Filed: 1945-09-27
Abstract: <PICT:0619761/III/1> An apparatus for controlling chemical reactions of short duration comprises in combination an elevated catalyst regeneration vessel 3, a reaction vessel 1 positioned below the regeneration vessel, a stand-pipe 4 connecting the regeneration vessel with the reaction vessel so as to conduct a natural flow of the fluidized catalyst from the regeneration vessel to the bottom inlet of the reaction vessel, means such as a pipe 20 and a distributing screen 21 for introducing a gasiform reactant into the bottom inlet of the reaction vessel so as to pick up and carry along in suspension through the reactor to its upper outlet the fluidized catalyst flowing from the stand-pipe, the outlet of the reactor being substantially below the level of fluidized catalyst in the regeneration vessel, a catalyst separating device 10, 10a at the outlet of the reaction vessel for directly receiving the catalyst suspension discharged from the reaction vessel and for separating centrifugally and by gravity the catalyst from the gaseous reaction products, and means such as a pipe 15 for injecting a quenching medium into the gaseous reaction products as or immediately after they are separated from the catalyst discharged into the separating device.  A constriction S of which more than one may be provided imposes a pressure differential between the reaction zone and the regenerator stand-pipe.  A pipe 18 returns the fluidized catalyst from the separating device to the regeneration vessel; and a valved draw-off pipe 9, a valved auxiliary stand-pipe 9a and a catalyst recycle line 50 are provided to control adjustably the level of the catalyst in the regenerator, the catalyst temperature and the amount of catalyst passing to the reaction zone.  The regenerator is provided with cooling tubes 3a, an auxiliary fuel injection line 3b and a gas inlet 3c.  A line 30 is provided for the removal of the reaction product.  Suitable quenching materials include condensable liquids of high latent heat or cold solids such as fine sand, brick dust, carborundum powder, silica gel, powdered metals or alloys, or catalyst.  The use of the above apparatus for the dehydrogenation of butene is described employing a temperature of 1050-1250 DEG  F., a contact time of 1/2 -5 seconds, and a catalyst of molybdenum oxide, chromium oxide, molybdenum sulphide, chromium sulphide, nickel sulphide, tungsten sulphide or other known dehydrogenation catalyst having a size of 100-500 mesh.  The apparatus is also applicable to the cracking of hydrocarbon gases or vapours at 1800-2600 DEG  F. to produce acetylene, ethylene and other low-molecular weight olefins and hydrogen.ALSO:<PICT:0619761/IV(b)/1> An apparatus for controlling chemical reactions of short duration comprises in combination an elevated catalyst regeneration vessel 3, a reaction vessel 1 positioned below the regeneration vessel, a stand-pipe 4 connecting the regeneration vessel with the reaction vessel so as to conduct a natural flow of the fluidized catalyst from the regeneration vessel to the bottom inlet of the reaction vessel, means such as a pipe 20 and a distributing screen 21 for introducing a gasiform reactant into the bottom inlet of the reaction vessel so as to pick up and carry along in suspension through the reactor to its upper outlet the fluidized catalyst flowing from the stand-pipe, the outlet of the reactor being substantially below the level of fluidized catalyst in the regeneration vessel, a catalyst separating device 10, 10a at the outlet of the reaction vessel for directly receiving the catalyst suspension discharged from the reaction vessel and for separating centrifugally and by gravity the catalyst from the gaseous reaction products, and means such as a pipe 15 for injecting a quenching medium into the gaseous reaction products as or immediately after they are separated from the catalyst discharged into the separating device.  A constriction s of which more than one may be provided imposes a pressure differential between the reaction zone and the regenerator stand-pipe.  A pipe 18 returns the fluidized catalyst from the separating device to the regeneration vessel; and a valved draw-off pipe 9, a valved auxiliary stand-pipe 9a and a catalyst recycle line 50 are provided to control adjustably the level of the catalyst in the regenerator, the catalyst temperature and the amount of catalyst passing to the reaction zone.  The regenerator is provided with cooling tubes 3a, an auxiliary fuel injection line 3b and a gas inlet 3c.  A line 30 is provided for the removal of the reaction product.  Suitable quenching materials include condensable liquids of high latent heat or cold solids such as fine sand, brick dust, carborundum powder, silica gel, powdered metals or alloys, or catalyst.  The use of the above apparatus for the dehydrogenation of butene is described employing a temperature of 1050-1250 DEG  F., a contact time of 1/2 -5 seconds, and a catalyst of molybdenum oxide, chromium oxide, molybdenum sulphide, chromium sulphide, nickel sulphide, tungsten sulphide or other known dehydrogenation catalyst having a size of 100-500 mesh.  The apparaatus is also applicable to the cracking of hydrocarbon gases or vapours at 1800-2600 DEG  F. to produce acetylene, ethylene and other low-molecular weight olefins and hydrogen.