GB339291A - Improvements in or relating to the cracking of hydrocarbon oils - Google Patents

Abstract

339,291. Triggs, W. W., (Panhandle Refining Co.). June 29, 1929. Divided on 337,380. Hydrocarbons, cracking; column stills.-Oils are cracked by preheating them in a coil 57 passing the preheated oil into a vaporizing zone 1, passing the vapours from this zone into a cracking coil 56 and fractionally condensing the cracked vapours in a series of dephlegmators and fractionating columns 6, 7, 8 by indirect interchange of heat with make-up oil or condensate which is passed through coils 26', 26<11>, 26<111>, 27, 27<1>, 28 and by direct interchange of heat with condensate injected through a valved pipe 18. The uncondensed vapours passing from the tower 8 are cooled in a condenser 9 and condensate is collected in a receiver 10. The residual vapours and gases are drawn through a pipe 30 by a pump 14 and passed through a pipe 42 to an absorption tower 11 where the vapours are condensed by washing them with the condensate collecting at the bottom of the tower 8 which is withdrawn by a pump 15 through a heat exchanger 17 and injected through a valved pipe 31. The condensate formed in the tower 8 is withdrawn by a pump 16 and forced through the heat exchanger 17 or a bye-pass x into the tower 8 through a valved pipe 33. The preheating and cracking coils 56, 57 are contained in one unit divided into two chambers 2, 2<a> by a perforated partition 63<a>, the gases being drawn off through a flue 60 communicating through valved openings 58, 59 with the preheating chamber. Heating burners 61, 62 are provided in both chambers, the burners 61 being turned on full only when bringing the plant on stream. In a modified form, Figs. 2 and 3, the chambers 2, 2<a> are placed side by side and divided by a wall 63 down which the gases of combustion pass from the burners 62 which are placed in extensions 2y of the chamber 2. The combustion gases pass to the flue 60 through openings 58, 59, the proportion of gases passing through either opening being adjusted by means of dampers. The application is similar to that described in Specilcat,io.ns 337,380, and 340,949, [Group III]. Specification 16713/14 also is referred to.