GB650486A - Improvements in or relating to the thermal treatment of hydrocarbons - Google Patents

Abstract

<PICT:0650486/IV (b)/1> <PICT:0650486/IV (b)/2> Apparatus for the thermal treatment of a liquid hydrocarbon charging stock comprises a liquid-container connected by separate valve-controlled pipes to a number of vaporizers which are connected to a corresponding number of reactors mounted within a common furnace, each reactor having quenching means at the outlet, and a separate outlet pipe for leading the quenched products from each reactor to a common collecting means. The apparatus may be used for the production of aromatic hydrocarbons and olefines from hydrocarbons boiling within the range 50-400 DEG C. by thermal treatment in the vapour phase at temperatures between 500 DEG and 800 DEG C. Liquid hydrocarbon is fed under pressure through pipe 10 (Fig. 1) and pipes 11 into vaporizers 12 contained within heating unit 17. Each feed-pipe 11 is provided with a valve 26 and flow-indicator 27. Vaporizers 12 are connected by pipes 13 to reactors 14 mounted within furnace 15 fired by oil or gas burners 16 (see also Fig. 2). The flue gases leaving furnace 15 pass to unit 17 through duct 19 and over baffle 20; the spent gases leave unit 17 through duct 22. Means 25 for quenching the products from the reactors are provided at their outlet ends. Each reactor has an outlet pipe 23 connected by a valve 32 to a common off-take 24 leading to a pitch-pot and cooler (not shown), and by a valve 34 to off-take 35. The reactors are free to expand at their upper ends where expansion-indicators 38 may be mounted to indicate the temperature within the reactor. If the back-pressure in any reactor (indicated by gauge 29) becomes high owing to carbon-choking, it is cut out of circuit by closing valves 26 and 32, and water or a mixture of air and steam (or inert gas) is fed into it through pipe 31 or pipe 30 respectively; the gases from the reactor are then exhausted through off-take 35 and stack 36. The reactors may be in the form of coils instead of straight tubes. Specifications 552,216, 574,973, 575,766, 575,771, 650,485 and 650,487 are referred to; and the Provisional Specification refers in addition to Specifications 574,963, 575,768, 575,769 and 575,770.ALSO:<PICT:0650486/III/1> <PICT:0650486/III/2> Apparatus for the thermal treatment of a liquid hydrocarbon charging stock comprises a liquid-container connected by separate valve-controlled pipes to a number of vaporizers which are connected to a corresponding number of reactors mounted within a common furnace, each reactor having quenching means at the outlet, and a separate outlet pipe for leading the quenched products from each reactor to a common collecting means. Accurate control of the feed to each reactor and the avoidance of excessive carbon-formation, is thereby achieved. The apparatus may be used for the production of aromatic hydrocarbons and olefines from hydrocarbons boiling within the range 50-400 DEG C. by thermal treatment in the vapour phase at temperatures between 500 DEG and 800 DEG C. Liquid hydrocarbon is fed under pressure through pipe 10, Fig. 1, and pipes 11 into vaporizers 12 contained within heating unit 17. Each feed pipe 11 is provided with a valve 26 and flow-indicator 27. Vaporizers 12 are connected by pipes 13 to reactors 14 mounted within furnace 15 fired by oil or gas burners 16 (see also Fig. 2). The flue gases leaving furnace 15 pass to unit 17 through duct 19 and over baffle 20; the spent gases leave unit 17 through duct 22. Means 25 for quenching the products from the reactors 14 are provided at their outlet ends. Each reactor has an outlet pipe 23 connected by a valve 32 to a common off-take 24 leading to a pitch-pot and a cooler (not shown), and by a valve 34 to off-take 35. The reactors are free to expand at their upper ends where expansion-indicators 38 may be mounted to indicate the temperature within the reactors. Alternatively, pyrometers may be fitted at a number of points within the reactors. If the back-pressure in any reactor (indicated by gauge 29) becomes high owing to carbon-choking, it is cut out of circuit by closing valves 26 and 32, and water or a mixture of air and steam (or inert gas) is fed into it through pipe 31 or pipe 30 respectively: the gases from the reactor are then exhausted through off-take 35 and stack 36. The reactors may be in the form of coils instead of straight tubes. Specifications 552,216, 574,973, 575,766, 575,771, [all in Group IV], 650,485 and 650,487 are referred to; and the Provisional Specification refers in addition to Specifications 574,963, 575,768, 575,769, [all in Group IV], and 575,770.