GB788293A - Improvements in or relating to apparatus for contacting gases with finely divided solids - Google Patents

Abstract

In apparatus for hydroforming hydrocarbons in the presence of a dense fluidized mass of finely-divided catalyst 12, Fig. 1, the feed and catalyst are introduced at 18 into vessel 10, catalyst is removed at 28, and one or more cyclone separators 36, 54 arranged in the upper part of the vessel are provided with diplegs 38, 56 leading to U-bends 40, 58 from which risers 42, 63 extend upwardly; gas is introduced at 44, 62 to fluidize the catalyst in the diplegs and risers, and additional gas enters at 48, 66 to reduce the density of the fluidized mass in the risers. This arrangement permits the height of the vessel above the fluidized bed to be reduced and provides seals in the diplegs between the cyclones and the fluidized bed to prevent reversal of flow of catalyst in the diplegs. Catalyst is withdrawn from vessel 10 through reservoir 24 into which stripping gas enters at 32. The gases <PICT:0788293/IV (b)/1> <PICT:0788293/IV (b)/2> leaving the bed 12 pass in series through the separators 36, 54 and leave the vessel at 70. In a modification, Fig. 2, the U-bends are replaced by lift pots 154, 184. The dipleg from primary separator 136 leads to seal pot 142 into which gas is introduced at 144 and from which catalyst overflows into bed 112. Dipleg 152 from secondary separator 148 extends into lift pot 154 from which riser 158 extends upwardly; aerating gas is fed in at 172 and additional gas is introduced into riser 158 through pipe 164. Pipe 182 from tertiary separator 174 extends outside the vessel 110 to lift pot 184 which operates in the same way as lift pot 154. The apparatus will operate with varying levels of the fluidized bed, e.g. at 114 or 176. Each catalyst separation stage may comprise more than one cyclone, with the diplegs leading to a common lift-pot. An alumina-molybdenum oxide catalyst may be used and hydroforming carried out at a pressure of 100-300 p.s.i.g. and a temperature of 850-950 DEG F.ALSO:<PICT:0788293/III/1> <PICT:0788293/III/2> In apparatus for effecting contact between a gas and a dense fluidized mass of finely-divided solids 12, Fig. 1, gas and solids are introduced at 18 into vessel 10, solids are removed at 28, and one or more cyclone separators 36, 54 arranged in the upper part of the vessel are provided with diplegs 38, 56 leading to U-bends 40, 58 from which risers 42, 63 extend upwardly; gas is introduced at 44, 62 to fluidize the solids in the diplegs and risers, and additional gas enters at 48, 66 to reduce the density of the fluidized mass in the risers. This arrangement permits the height of the vessel above the fluidized bed to be reduced and provides seals in the diplegs between the cyclones and the fluidized bed to prevent reversal of flow of solids in the diplegs. Solids are withdrawn from vessel 10 through reservoir 24 into which stripping gas enters at 32. The gases leaving the bed 12 pass in series through the separators 36, 54 and leave the vessel at 70. In a modification, Fig. 2, the U-bends are replaced by lift pots 154, 184. The dipleg from primary separator 136 leads to seal pot 142 into which gas is introduced at 144 and from which solid overflows into bed 112. Dipleg 152 from secondary separator 148 extends into lift pot 154 from which riser 158 extends upwardly; aerating gas is fed in at 172 and additional gas is introduced into riser 158 through pipe 164. Pipe 182 from tertiary separator 174 extends outside the vessel 110 to lift pot 184 which operates in the same way as lift pot 154. The apparatus will operate with varying levels of the fluidized bed, e.g. at 114 or 176. Each solid separation stage may comprise more than one cyclone, with the diplegs leading to a common lift-pot. The apparatus may be used for catalytic cracking in the presence of silicaalumina catalyst, for hydroforming in the presence of alumina-molybdenum oxide catalyst, or for catalyst regeneration with air. Reference is also made to processes of thermal cracking, coking and adsorption.