US2947681A

US2947681A - Process for producing high quality fuels from crude residua

Info

Publication number: US2947681A
Application number: US560666A
Authority: US
Inventors: Chester L Read; William O Heilman
Original assignee: Exxon Research and Engineering Co
Current assignee: ExxonMobil Technology and Engineering Co
Priority date: 1956-01-23
Filing date: 1956-01-23
Publication date: 1960-08-02
Anticipated expiration: 1977-08-02

Description

Aug. 2, 1960 CRUDE OIL c. L. READ ET AL PROCESS FOR PRODUCING HIGH QUALITY FUELS FROM CRUDE RESIDUA Filed Jan. 2:, 1956 1 CA7ZILYTIC CRACKER j P 65 '9 DEAS HALTER inl L SOLVENT ,63 4' H20 Q 3o 25 fi (27 3! COKER} F 42 4 47 4! 44 i COAL 43 T '49 COKER Chester L. Read ,nveniors William O. Heilman By Attorney United 2,947,681 Patented Aug. 2., 1960 7 PROCESS FGR PRODUCING HIGH QUALITY FUELS FROM CRUDE RESIDUA Filed Jan. 23, 1956, Ser. No. 560,666 4 Claims. (Cl. 208-55) The present invention is concerned with an improved method of processing crude oil, and more particularly, relates to a method of processing the higher boiling components of crude oil for the manufacture of high quality motor fuels, lubricating oils and the like. The invention is specifically concerned with an integrated operation for the removal of asphaltic constituents from the higher crude oil fractions in order to prepare better feed oils for subsequent cracking operations, particularly for a catalytic cracking operation.

It is well known in the art to distill crude oil in order to segregate various boiling fractions such as motor fuels, gas oils, residual oils and the like. It is also known that due to an increasing demand for motor fuels, it is desirable to crack not only conventional gas oil fractions but also to crack the higher boiling constituents such as those constituents boiling up to about lO0-ll00 F. and higher. However, these fractions have been diflicult to process efficiently due to the fact that these fractions contain metallic-organic contaminants and complex asphaltic hydrocarbon molecular constituents. ,In accordance with the present invention, these undesirable metal-containing and asphaltic constituents are removed in an integrated operation, resulting in the production of increased yields of high quality gasolines, lube oils and the like. In accordance with the present invention, the crude oil is distilled, a high boiling fraction segregated, and this fraction then treated with a product derived from a thermal coking operation of carbonaceous material such as coal or heavy petroleum residua.

The process of the present invention may be fully understood by reference to the drawing illustrating embodiments of the same. Referring specifically to the drawing, a crude oil is introduced into distillation zone 10 by means of feed line 11. The distillation zone is operated in a conventional manner in order to segregate various boiling hydrocarbon fractions. Gases are removed overhead by means of line 12, while motor fuel constituents are removed by means of line 13. A conventional gas oil fraction is segregated by means of line 14 and passed into a catalytic cracking zone 15. A heavy residual fraction comprising those constituents boiling above about 850-950 F. is removed by means of line 16. It is to be understood that distillation zone 10 may comprise a plurality of zones and that other fractions or streams may be segregated.

Fluid catalytic cracking zone 15 is a conventional unit operated at a pressure in the range from about 2100 pounds and at a temperature in the range from 900- 1050 F. Typical catalysts are used as, for example, silica-alumina and the like, which are maintained in a fluid state by means of upflowing gases.

In accordance with a specific adaptation of the present invention, the residual fraction removed by means of line 16, is segregated into two streams. One stream is introduced into a deasphalting zone 17 by means of line 18. In this zone the fraction is contacted with a deasphalting solvent, such as a liquefied normally gaseous hydrocarbon, such as propane, butane and the like.

The deasphalting solvent is introduced into zone 17 by means of line 19. The asphalt is removed by means of line 20, while the deasphalted oil is removed by means of line 21. This stream after removal of the solvent is preferably passed to fluid catalytic cracking zone 15. A portion of the stream may be removed by means of line 23 and employed as a high quality lube oil.

In accordance with the present invention, a high boiling aromatic wash oil, secured as hereinafter described,

is introduced into the top of zone 17 by means of line 24.

Deasphalting zone 17 may comprise any suitable number and arrangement of stages. The temperature employed may vary in the range from about l20220 F., preferably in the range from about 140-200 F. The amount of solvent used per volume of oil is in the range from about 0.5-l0, preferably about 2-6 volumes of solvent per volume of oil.

The amount of wash oil introduced by means of line 24 is preferably in the range from 5-40 volume percent based on the oil feed. The preferred quantity is from about 10-20% based on oil feed. The wash oil introduced by means of line 24 functions as a demetalizing and deasphalting aid. In general, this wash oil should contain at least 60% aromatics, and preferably contain from -90% aromatics. The wash oil should have a low metal content, preferably less than 5 parts per million of vanadium and nickel. The initial boiling point of the wash oil should be above about 850 F., preferably above 950 F.

In accordance with the specific concept of the present invention, the second portion of the crude residuum is introduced into coking zone 26 by means of line 25. In zone 26 the temperature is maintained in the range from about 900l050 F. and the pressure is in the range from about 2-100 p.s.i.g. It is preferred that the coking operation be a fluid coking operation. In this type of operation, the feed is sprayed into the unit and contacted with small particles of coke which are heated to the reaction temperature by partial combustion in a second vessel.

The coking products are Withdrawn from coking zone 26 by means of line 27 and passed to a distillation zone 28. In this zone temperature and pressure conditions are adapted to segregate a gaseous fraction which is removed by means of line 29, a fraction boiling in the motor fuel boiling range which is removed by means of line 30, a heavier fraction which is removed by means of line 31 and a deasphalting aid fraction which is re moved by means of line 24. At least a portion of this fraction, as described heretofore, is recycled or passed to deasphalting zone 17. A portion of the fraction may be removed from the system by means of line 32.

A preferred mode of operation is to pass the stream, removed by means of line 24, to a solvent extraction zone 60 by means of line 61. In this zone the oil is contacted with a solvent, such as phenol, furfural and the like, which solvents are characterized by having a preferential selectivity for the aromatic type constituents as compared to the more paraflinic type of constituents. Conditions are adjusted to secure the formation of a solvent extract phase and a raffinate phase. The solvent, such as phenol, is introduced into solvent treating zone 60 by means of line 63. The amount of solvent employed may vary in the range from 0.5 volume of solvent to 10 volumes of solvent per volume of oil. A preferred amount of solvent is about 1-2 volumes of solvent per volume of oil. The raflinate phase, relatively low in aromatics, is removed from treating zone 60 by means. of line 62. The solvent extract phase, relatively rich in aromatics, is removed from treating zone 60 by means Ts bbrstbi as? 'nrf ssb s ssbditisbs' is s 3. a s a ed 9 bye bysrb a by s ib 6 a g'sssibs isn lQb st tbsb s bb li s n he ras e 9 aili -ra ses a I by me g lib is?! whi w t a sen s ps b bm bk an equally desir source of the deasphalting wash oil is from acoal cohing s2 ien- In thi YP ;.f e mal b y nsbp rst b s s ibt b b s int i ssksy 4 by m s sf li 4 Temperature conditions in the coker are maintained in the a e om absb Rab i-22b F- s kin Pre 1. 9 s are withdr w bm m 4 b m s l bs 4 a Ps s is s s nersti n r ii l st s n 4- s ad .p sssb ssns tib a s ada te t rab s tsr irsstib b means s s 45 4 sa A es ual b ib i rs ys b ans o lie 4? end-a ast a s ibss f th s P od is Pa e to th deasphalting zone 17 by means of line 24. The remainn r b t sn s sms s a P e bs b m an f 31. 43- tlsresea n i may e l abls sls b sin s si bt s to soly n sat n n 0 t n ent a e he r me i constituents.

The present invention contemplates the employment as a isasnh t ns d, a h bb na h l roma i t a tion which is low in metallic content. In general, the fraction should boil in the range above about 850 F., pr fe abl in he a ssa ve'a 9 0 F- A ypibs satisfactory wash oil fraction is as follows:

4 A typical satisfactory oil from a coal tar is asfollows: Initial boiling point F 900 point F 1050 Conradson carbon 42.2 Insoluble 86 naphtha 50 Specific gravity 1.268

While it is preferred that the coker gas oil be secured as described, it to be understood that the coker gas oil may be derived from a different crude residu rather than from the sam e crude residuum. s a

What is claimed is:

1. An improved process for the produetionof apetroleurn fuel which comprises distilling a crude oil under 'conditionsyielding a relatively high boiling residual fraction, separating said residual fraction into a first portion and a second portion, subjecting said first portion to a coking operation at pressures of from 2 to 100 ps sn at tem era u es b f m ab u 999.19 1950 F. to form coking products, including a heavy aromatic bas n s r est s i bs r m tisiras ion f in e sbkingvv Prod s t bdbsin sai heav a m is trss bn as a Wash o int b ts of a dsasphaltin mus, ntr bs n a e o d P r on i n. in ermediate Pa t sf a s ha zb a i rs bsiti a asnbal in sb b i tbs lower u f s id lsas bal ae z t. .s, se re t n s i as hl d il n s b'ssin seidd as phalted oil to a catalytic cracking operation and therg: bits? ae in a i h a it e IQII! massa e prod s i 2- Prbbss s d n d b claim 1 w erein sa d wa h i sb t in s h n 5 pa t Psi m l ion of vanad um a n s sl- Y P-re ess s d in d b c im 1 whe e n sa d-fl as: b ib bb bm r s a uefied iibrmall -s s us h b ss bs PIQS$ a dsfinsd by la m 1 wherein said ash-nil sbmaibs. t lsast Ps ssm ar ma ics- References Cited in the fileof this patent UNI ST ES ATE TS 2,340,974 My rs Fob- .8, 1944'. 2,677,604 Nelson May 4, 1954 2,709,637 Knox Jan. 25, 1955 2,727,853 Hennig Dec. 20, 195.5 2,793,167 Webber May 21, 1957 2,793,168 Corneil et a1. May 21, 19.57 2,800,433 Read July 23,, 1957- ..b' "um

Claims

1. AN IMPROVED PROCESS FOR THE PRODUCTION OF A PETROLEUM FUEL WHICH COMPRISES DISTILLING A CRUDE OIL UNDER CONDITIONS YIELDING A RELATIVELY HIGH BOILING RESIDUAL FRACTION, SEPARATING SAID RESIDUAL FRACTION INTO A FIRST PORTION AND A SECOND PORTION, SUBJECTING SAID FIRST PORTION TO A COKING OPERATION AT PRESSURES OF FROM 2 TO 100 P.S.I.G. AND AT TEMPERATURES OF FROM ABOUT 900 TO 4050* F. TO FORM COKING PRODUCTS, INCLUDING A HEAVY AROMATIC FRACTION SEGREGATING SAID HEAVY AROMATIC FRACTION FROM THE COKING PRODUCTS, INTRODUCING SAID HEAVY AROMATIC FRACTION AS A WASH OIL INTO THE TOP OF A DEASPHALTING ZONE, INTRODUCING SAID SECOND PORTION INTO AN INTERMEDIATE POINT OF SAID DEASPHALTING ZONE, INTRODUCING A DEASPHALTING SOLVENT INTO THE LOWER AREA OF SAID DEASPHALTING ZONE, SEGREGATING A DEASPHALTED OIL AND SUBJECTING SAID DEASPHALTED OIL TO A CATALYTIC CRACKING OPERATION AND THEREAFTER RECOVERING A HIGH QUALITY FUEL FROM THE CRACKED PRODUCTS.