GB317507A - Improved process of heat treating hydrocarbon oils - Google Patents

Abstract

317,507. Osterstrom, R. C., and Wagner, C. R. May 9, 1928. Hydrocarbons, cracking. - Hydrocarbon oils are cracked with substantial elimination of carbon deposition by reducing to the vapour phase at 650‹ F.-850‹ F., by means of a pipe still 3 and a steam jet 9 and an expansion chamber 10; separating residual liquid and carbon in two stages by a condenser- 14 and a separator 15; substantially instantaneously raising the temperature to converting temperature in excess of about 1000‹ F. at a pressure not above 30 lb. per sq. in., the conversion being completed in a period of time less than two seconds in the presence of a catalyzer such as ferrous oxide, nickel oxide or other metal oxide capable of two or more stages of oxidation in a converter 16, the top pass 21<a> of the cracking tube 21 being arranged at the hottest part of the furnace; abruptly cooling to a temperature less than about 600‹ F. by means of a spray 29 of oil at 200‹ F. or less, the temperature range of 600-1000‹ F. being substantially avoided throughout the operation. The cooling oil 29 is circulated continuously in the cooling circuit, and also, preheated by the reaction products, passes by a pipe 1 to the pipe still and thence to the reaction chamber 16. Fractionation of the products of the reaction is effected in a tower 36 communicating with a condenser 41, separator 42 and storage tank 43. The catalytic material in the converter tube 21<a> is in the form of tapered rods so that the effective area of flow is reduced at the inlet end to produce a high velocity of flow at that point. The converter shown may be replaced by a simple tube heated electrically, the area of flow within it being adjusted by a tapered rod of catalyst as before.