GB383616A - Method and installation for transforming the heavy hydrocarbons into products with low boiling point - Google Patents

Abstract

In a vapour phase cracking process the exhausted catalyst is discharged from the reaction chamber periodically and regenerated in a separate furnace by blowing air therethrough with or without steam and oxides of nitrogen. Crude oils &c. are pumped from a tank 1 through a heat exchanger 5 to a tubular heater 8 where the oil is preheated to 380-450 DEG . The oils pass to a vapour separator 10 and the vapours mixed with steam from a pipe 12 are superheated in a tubular heater 15 and then pass into a reaction chamber 16 through a sprinkler 25. A second chamber 16a may be used alternately with the chamber 16. The latter comprises a cylindrical box of iron sheeting filled with catalyst from a hopper 60 heated by exhaust gases from the furnace 21 which heats the chamber 16. The catalyst is fed through a tube 112 provided with a shutter 113 operated by a cable 113a and comprises spherical grains of bauxite, silica, infusorial earth, &c. impregnated with metallic oxides. The cracked vapours are removed through a tube 28 containing a removable perforated tube 27 and a pipe 31 in the heat exchangers to a fractionating tower 32 from which condensate is returned to the tank 1 while vapours pass through a preheater 35 and purifying and polymerizing chambers 38, 39 used alternately to a condenser 42 from which condensate is passed to a receiver 44 from the upper part of which gases are drawn off through a line 111. The exhausted catalyst is removed by reciprocating a piston 51 in an extension 50 of the tube 28, the catalyst falling into boxes 54 which are removed bodily to the regenerating furnace, Fig. 2. The latter comprises an oven <PICT:0383616/III/1> <PICT:0383616/III/2> <PICT:0383616/III/3> divided into three chambers 70, 71, 72 each containing a framework 73 on which the catalyst boxes 54 are mounted. Air is admitted through conduits 75 to collectors 76 and distribution tubes 80. The boxes 54 comprise two perforated partitions 91, 92 between which the catalyst admitted through a conduit 95 is spread and to which air is admitted by a tube 98, chamber 97, and perforated tubes 100 covered by circular baffles 101. In a modification the catalyst boxes are fixed obliquely in the furnace and catalyst is fed thereto through a movable hopper.