Patent GB-390846-A (GB)
Title: Improvements in or relating to the conversion of hydrocarbons into other hydrocarbons of lower molecular weight
Filed: 1931-10-01
Abstract: <PICT:0390846/IV/1> <PICT:0390846/IV/2> Hydrocarbon oils are cracked by passing them, preferably in vapour form, in the form of a thin annular sheet both surfaces of which are heated otherwise than by heat exchange with the reactant fluid itself.  The thickness of the sheet is small in itself, for instance from \ba1/4\be to \ba1/20\be inch, and is of the order of 0,2 of the radius of the annulus or less.  The product may contain ethylene and other gaseous olefines of low molecular weight, in very large quantities.  The heating of the annular sheet may be effected by hot gases, superheated steam, or electrically, the temperature may be 500-1000 DEG  C., and the pressure ordinary, reduced or increased.  The walls of the apparatus may be made of or coated with substances assisting the reaction such as nickel, copper, iron, alloys of iron, chromium, and nickel.  The apparatus described comprises an outer shell 1 containing four pairs of tubes 5, 6, 5a, 6a, 5b, 6b, and 5c, 6c, the annular spaces being enlarged at each end to form inlet and outlet chambers 7, 8 communicating with the inlet and outlet 9, 10.  At the inlet end hot gases are admitted through a perforated pipe 11 and the gases leave by a pipe 12.  The reaction tubes are held in position by web supports 13 extending to the outer case and supports 14 between the tubes.  The heating gases may flow in any direction in relation with the reaction fluid.  Concentric annular spaces may be used such as those described in Specification 390,845.ALSO:<PICT:0390846/III/1> <PICT:0390846/III/2> Hydrocarbon oils are cracked by passing them, preferably in vapour form, in the form of a thin annular sheet both surfaces of which are heated otherwise than by heat exchange with the reactant fluid itself.  The thickness of the sheet is small in itself for instance from \ba1/4\be to \ba1/20\be inch, and is of the order of 0,2 of the radius of the annulus or less.  The product may contain ethylene and other gaseous olefines of low molecular weight, in very large quantities.  The heating of the annular sheet may be effected by hot gases, superheated steam, or electrically; the temperature may be 500-1000 DEG  C., and the pressure ordinary, reduced or increased. The walls of the apparatus may be made of or coated with substances assisting the reaction such as nickel, copper, iron, alloys of iron, chromium and nickel.  The apparatus described comprises an outer shell 1 containing four pairs of tubes 5, 6; 5a, 6a; 5b, 6b; 5c, 6c, the annular spaces being enlarged at each end to form inlet and outlet chambers 7, 8 communicating with the inlet and outlet 9, 10. At the inlet end hot gases are admitted through a perforated pipe 11 and the gases leave by a pipe 12.  The reaction tubes are held in position by web supports 13 extending to the outer case and supports 14 between the tubes.  The heating gases may flow in any direction in relation with the reaction fluid.  Concentric annular spaces may be used such as those described in Specification 390,845.