US2001159A - Treatment of hydrocarbon oil - Google Patents

Description

A MWWWW INVENTOR PZmSuJu UZCKMI y 5- J. D. SEGUY TREATMENT OF HYDROCARBON OIL Filed Aug. 16. 1930 we mmumz nz.

, JEAN DELATTRE SEGUY BY F Wm ATTORNEY Patentecl May 14, 1 935 v e TREATMENT OF HYDROCARBON 01 Jean Delattre Seguy, Chicago, 111., assignor to Universal Oil Products Compan Chicago, 111., a a corporation of'South Dakota Application August 16, 1930, Serial No. 475,704 I e I e l 1 Claim. (01. 196-48)" t a a v a This invention relatesto the treatment'of hyline or light fractions, that vaporizing but non drocarbon oils, and refers more particularly to cracking temperatures be reached in the heating the conversion of high boiling hydrocarbons into element it. In this alternative such pressure lower boiling hydrocarbons. may be maintained in the heating element Ill OFFICE In one specific embodiment, the invention conthat only a limited vaporization takes place, additemplates aprocess for the treatment of hydrotional vaporization of the charging stock taking carbon .oilswhich comprises subjecting relatively place upon reduction of pressure by means of clean oils such as reflux condensates (obtained valves [3 or E5 or both, andby admixture of the from conversion under pressure, or from addioil leaving heating element It with the residuum tional vaporization under reduced pressure of the from chamber i8. a

residuum from the conversion zone) to cracking On the other hand, if the chargingstockfed conditions, these reflux condensates being obto the process is a residuum or topped crude,

tained by subjecting the raw oil to be treated in conditions in the heating element Ill may be t the process (with or without preliminary indesuch that a conversion temperature is reached l5 pendent heat treatment at temperatures such and acondition is maintained to obtain substanl5 that vaporizationwith or without cracking may tial conversion of the raw oil under pressure. take place) to direct heat exchange with the Raw oil, if desired, may be fed directly to the unvaporized oil from the primaryreaction zone heating element iii; if the latter is used, and as it undergoes flash distillation. In this manner without passingthrough preheatingcoil 6. This ,the coke-forming constituents of the raw oil are may be done by proper manipulation of valve I6 20 .removed from the processin admixture with the in line; IS. The oil leav ng t e h at leme t residuum from the-so called flash chamber. The Hl, if the latter is used, is discharged through light constituents cfthe raw oiland those formed li e 92 havi Valve l3 and is h Dassedthrough by its preliminaryheatftreatment are removed line I 4 having valve l5 combining with the un- Zli jwi hvthe vaporizedparts of the .unvaporized oil vaporized oil from reaction chamber lil, and disfrom the primary reaction zone andthese vaporcharging therewith into flash chamber lLwhere-E ized constituents" are then subjected to condenin vapors separate from unvaporized residue. tsation to form so called flash condensate which The unvaporized oil enteringthe flash chamis subjected to cracking treatment in the primary ber H is withdrawn from the reaction chamber reactionzone in admixture with reflux condenlttthrough line 2!; controlled by valve 20; and 3c sate formed from the vapors evolved in said treatpasses through line it and valve I5 into theflash ment in said primary reaction zone. v chamber l1; owing tothe reductionin pressure i The utilityof the invention as well as the ob at the valve and the latent or stored heat of jects and advantages thereon-will be better unthe oil, a substantial portion of the residue leavderstood byreferring to the accompanying dra'vving the reaction chamber vaporizes. The vapors 35 o ing, whichis a diagrammatic side elevational from the flash chamber which comprise vapors view of an apparatus suitable for carrying out the evolved from the unvaporized oil removed from process of the inventions reaction chamber l8 and vapors evolved from the The raw oilcharging stock is fed through line raw oil charging stock, pass through line 22, con- *0 1,;valve2, and ispumped by pump 3 through line trolled by valve 23, into the flash dephlegmator 40 A, controlled b'y valve 5, through indirect heat 24 Where, owing to the cooling action of the raw vexchanger 6, line'land valve 8. -oil charging stock passing through the heat ex- Thereafter, this preheated raw oil may be changer 6, a substantial portion thereof conpassed through line 40, valve 44, and line M denses, The flash condensate thus produced 4? where it mixes with theunvaporized oil from the passes through line 25, valve 26, and may bear, reaction chamber l8 as will be hereafter expumped by means of pump 21 through lines 28 plained, or the raw oil from line 1 may be suband "29 and. valve 30, into the primary dephlegjected to additional heat treatment by passing tmatortl, where it meets the ascending vapors l through line 9 and valve 8 and thence into the from the reaction chamber I3 andcausesa parheating element I I] located in furnace setting H. tial condensation of the heavier components 50 In the heating element l0, depending upon the thereof. The combined flash condensate and composition of therawoil, conditions of vaporreflux condensate from the primarydephlegmaization with cracking or without cracking may tor 3! passes through line 3?, controlled byvalve be maintained, It is preferable, if the charging 33, and is pumped by means of pump 34 through is s o on a nsa u s a ropo tion 9 sa qine/35 into theheating element 36located in 5 furnace setting 31. Flash condensate from dephlegmator 24 may by-pass dephlegmator 3| in any desired proportion, being directly supplied to pump 34 through valve IS in line 28. The combined reflux and flash condensates are raised to conversion temperature in the heating element 36 and pass through transfer line 39, controlled by valve 38, into reaction chamber IS. The vapors leaving the reaction chamber l8 pass through line H, controlled by valve 42, into dephlegmator 3|, where interchange occurs, causing the condensation of the heavier components of thev-apors entering dephlegmator 3|. Additional coolingis accomplished by the introduction into the dephlegmator 3| of some of the low boiling products of the process. The vapors leaving dephlegmator 3| pass through line 43 controlled by valve 45, into cooler and condenser 46, through line 41, controlled by valve 48, into receiver 49. The liquid distillate of the process is withdrawn through line 50, controlled by valve 5|. The gases of the process are withdrawn through line 52, controlled by valve 53, which also serves as the pressure control valve upon the receiver.

The unvaporized residue referred to as flashed residuum which contains unvaporized heavy portions of the raw oil charging stock is withdrawn from the flash chamber through line 54, controlled by valve 55. The vapors leaving the flash dephlegmator 24 pass through line 51, controlled by valve 58, through cooler and condenser 59, controlled by valve 60, and through line 6| into receiver 62. The liquid product which accumulates in receiver 62 is withdrawn through line 63, controlled by valve 64. Any vapors or gases accumulating in the receiver 62 are withdrawn through line 65, controlled by valve 66. A portion of the final low boiling product of the processfrom receiver 49 may be withdrawn through line 61, controlled by valve 68, and pumped by means of pump 69 through line 12 and valve 13, into the primary dephlegmator 3| for the purpose of cooling the vapors arising therein and permitting control of the separation of the lower boiling components from the heavier boiling components.

The operating conditions of the process may be varied over a wide range, the temperature in the heating element 36 being preferably well within the cracking range, and preferably higher than that in the heating coil I0. I may maintain the so called vapor-phase conditions of cracking or high temperature heating within the heating coil 35.

As stated, when the charging stock does contain any fractions of the character of light distillates such as gasoline or naphtha, the temperature in the heating coil l0, may be sufficient to promote vaporization with no or little conversion or it may be such that under the conditions of operation substantial conversion takes place before the stock enters the chamber When the charging stockrcontains gasoline or like fractions then it is preferable that the temperature in the heating coil l0, if the latter is used, be one where no or only little conversion takes place, providing principally for the fractional distillation of the crude oil.

, The pressures on the system may vary from sub-atmospheric to high super-atmospheric, preferably maintaining a substantially super-atmospheric pressure upon the heating elements and the reaction chamber with either equalized or lowered pressure upon the remainder of the systhe afore-mentioned heat tern, but in all cases maintaining a substantially lower pressure upon the flash chamber and elements succeeding it.

With some conditions of operation, particularly when simple distillation with little or no cracking is to take place on the raw oil, I may maintain a pressure on heating element I0 only slightly higher than that on flash chamber As a specific example of the operating conditions and yields of products obtained by the operation of the process of my invention, a 30 degree A. P. I. gravity topped crude oil was charged to the process. A pressure of approximately 150 pounds per square inch and a temperature of approximately 910 F. was maintained upon the heating element It].

A temperature of approximately 950 F. and a pressure of approximately 200 pounds per square inch was maintained upon the heating element 36, and the pressure upon the reaction chamber It was approximately 200 pounds per square inch. The pressures upon the primary dephlegmator 3|, condenser 46 and receiver 49 were substantially equalized with respect to that upon the reaction chamber I8, showing some drop resulting from frictional resistance to flow through the system.

The pressures upon the flash chamber flash dephlegmator 24, flash condenser 59 and receiver 62 were substantially equalized, the pressure upon the flash chamber pounds per square inch.

A yield of approximately 65% of pressure distillate composed of 50% gasoline and 15% pressure distillate bottoms, all based on the raw oil charged to the system, was obtained. A yield of approximately 30% of flashed residuum containing less than 2% of suspended carbonaceous or pitchy matter and having a viscosity and gravity suitable for fuel was produced at the same time. the yield of gas was approximately 450 cubic feet per barrel of raw oil charged, and a small amount of carbon or coke was produced. Increasing the temperature on the heating element 36 increased the anti-knock value of the gasoline. In some cases, this varied over a range of 15% benzol equivalent as a function of increase in temperaure on the heating element 36. For example, with a temperature of 925 F. on the heating element 36, the benzol equivalent of the gasoline was approximately 45%, while at a temperature of 970 F., the benzol was approximately 65%.

As another illustration of a manner in which the invention of the process may be carried out when using a crude oil charging stock through the process, a 35 gravity crude oil containing approximately 13% of gasoline was charged to the process and passed through the heating coil l0 under a pressure of approximately 100 pounds and it was there raised to a temperature of approximately '700 F. The pressure upon the flash chamber H was in the neighborhood of 30 pounds per square inch and the condensate found therein and formed in the dephlegmator 3| was treated in the heating coil 36-where it was heated to approximately 930 F. under a pressure of approximately 225 pounds per square inch, the pressure on the reaction chamber I8 being equalized with that at the discharge of the heating coil 36. In this operation a yield of approximately 75% of pressure distillate was recovered which comprised 63% gasoline and 12% of pressure distillate bottoms, these percentages being based on the crude oil charged to the system. This gasoline and pressure distillate comprised the gasoline contained originally in the crude and recovered in the being approximately 35 l,

flash receiver 62. Marketable fuel oil was produced concurrently to the extent of about 20%,

of the crude oil charged to the process. The gasoline resulting from a mixing of the pressure distillate recovered in the receiver 49 and of the distillate recovered in the receiver 62, which amount has heretofore been stated, approximately 62% of the crude oil, had a benzol equivalent of approximately 40%. v

The examples show the results obtainable under one set of conditions, and are intended to serve only as illustrations;

I claim as my invention:

A hydrocarbon oil cracking process which comprisescpassing relatively clean hydrocarbon distillate in a restricted stream thru aheating zone and heating the same therein to cracking temperature under sufiicient pressure to maintain a substantial portion thereof in liquid phase, discharging the heated oil into a vapor separating zone maintained under cracking conditions of temperature and superatmospheric pressure and separating the same therein into vapors and unvaporized oil, removing the separated vapors and dephlegmating the same under superatmospheric .-pressure to condense insuificiently cracked fractions thereof as reflux condensate, separately removing the unvaporized oil from the separating zone and flash distilling the same in a flashing zone by pressure reduction, simultaneously with the foregoing operation independently heating fresh charging oil for the process, under a pressure higher than that prevailing in the flashing zone and without substantial cracking thereof, to a temperature adequate to distill a substantial portion thereof under the pressure of the flashing zone, introducing the thus heated chargingoil, prior to any substantial cracking thereof, to the flashing zone and vaporizing a substantial portion thereof in the flashing zone, removing the admixed flashed vapors and charging oil vapors from the flashing zone, separately removing residuum from the flashing zone and isolating the same from the process, dephlegmating the admixed vapors removed from the flashing zone independently of the vapors removed from. the separating zone and under the reduced pressurejof the flashing zone to condense heavier fractions thereof by passing the same in indirect heat exchange relation with said charging oil undergoing heating whereby the heat of the vapors is utilized to supply at least a portion of the heat required to distill the charging oil, and supplying such condensed heavier fractions and said reflux conden sate to the heating zone to constitute said relatively clean distillate.

JEAN DELATTRE SEGUY.

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