GB501560A - Process for the pyrolytic conversion of hydrocarbon oils - Google Patents

Abstract

501,560. Cracking, coking, and re-forming oils. UNIVERSAL OIL PRODUCTS CO. Nov. 30, 1937, No. 33129. Convention date, Nov. 30, 1936. [Class 32] In a combined process for subjecting separated fractions of crude oil stock to cracking, coking and reforming 'operations, a charging stock of wide boiling-range is fed through lines 2, 4, 13 with or without passage through a heat exchanger 12 into a fractionating tower 6 where it is separated into (a) a light gasolinenaphtha fraction taken overhead through line 48, (b) a relatively light reflux condensate taken off through line 26, and (c) a heavy fraction collected at the bottom of the tower and removed through line 18. If desired a stock of lower boiling-range may also be fed 'to the tower 6 through lines 7, 10, 13. The heavy fraction is cracked in the coil 20 while the light reflux condensate is cracked in the coil 31, and the products of both crackings are passed downwardly through a reactor 24 so as to be sprayed against the walls thereof. The liquid and vaporous reaction products are removed together through line 36 to an evaporator 38 where vapours are separated ; the vapours are passed through line 46 into the tower 6, and the liquid residues are fed through line 42 into the lower portion of a tower 45 where they are flashed with reduction of pressure. Alternatively, part of the residues may be removed to storage through line 95 and cooler 97 or passed through line 42<1> for treatment in a coil 171. From the flashing operation by fractionation in the tower 45, (1) a gasoline fraction is segregated and taken overhead through line 220 and cooler 222 to receiver 225, (2) a condensate is collected on plate 117 and. may be fed through lines 194, 197 into tower 6, or re-formed by heating it in coil 110 to high temperatures and then recycled in part through line 119 to the tower 45, (3) heavy residues are collected at the bottom of the tower, and removed through line 169, and, after passage through coil 171, are injected into coking vessels 177, 177<1> where they are reduced to coke with the aid of hot vapours from the coil 110 injected through lines 186, 186<1>, and also, if desired, with the aid of part of the products from coil 31 fed through line 182. Vapours from the coking vessels pass through line 193 into the tower 45. The light 'fraction taken overhead from the tower 6 through line 48 is in part condensed in cooler 53, to provide reflux for tower 6 and the major part is fed through line 50, where it is mixed with vapours taken overhead from the tower 45 through line 200, the mixed vapours being subjected to a final fractionation in a tower 52 from which gasoline of desired quality is removed through line 65 and cooler 67. to receiver 70, while a reflux condensate is removed through lines 85 107 and re-formed in the coil 110.. Temperatures specified for the various stages'comprise (1) coil 20, 455-510‹ C., (2) coil 31, 482- 540‹ C., (3) coil 110, 510-566‹ C., (4) coil 171, 428-566‹ C.