US2079187A - Treatment of hydrocarbon oils - Google Patents

Description

May 4, 1937.

J. D. sEGl JY TREATMENT OFHYDROCABBON OILS Filed Apil 30, 1932 Nb., ma/mkg -1?? dewfoz' L/an Za fire 5e APatented May 4, 1937 y UNITED STATES PATENT OFFICE 2,o79,1s7 TREATMENT oF HypnooAnBoN oms Jean Dclattre Seguy, Chicago, Ill., assignor to Universal Oil Products Company, Chicago, lll.,

a corporation of Delaware -Application April 30, 1932, Serial No. 608,516

(ci. 19e-so) Y, r

s claims.

This invention relates to the treatment of hydrocarbon oils and more particularly refers to an improved process and apparatus for the conversion of hydrocarbon oil `accompanied by reduction of the residual conversion products to substantially devolatilized petroleum coke.

The present invention makes possible the production of high yields of motor fuel of maximum anti-knock value from the conversion of heavier hydrocarbon oils. Reduction of the residual conversion products to petroleum coke of low volatility permits the recovery of high yields of light liquid products while retreatment of a regulated portionl of the light liquid product, in either vaporous or liquid state, under reforming conditions (conversion conditions which eifect the improvement of light oils in anti-knock value without materially altering their boiling range) permits the recovery of a iinal light distillate product of high anti-knock value. In the present invention these two advantageous features are practiced in such a way that one augments the other, i. e. the highly heated distillate product of the systemis utilized ata heat carrying medium to assist coking of the residual oil and devolatilization of the` coke.

One specific embodiment of the present invention may comprise subjecting a hydrocarbon oil to conversion temperature at superatmospheric pressure in a. heating coil and communicating reaction chamber, introducing the heated products into a reduced pressure coking zone wherein vaporous and residual liquid products separate and wherein residual liquid is reduced to petroleum coke of low volatility, subjecting vapors from the coking zone to lfractionation, returning the heavy components of the vapors, which are condensed by fractionation, to the heating coil forfurthenconversion, removing the lighter components of the vapors, remaining uncondensed by fractionation, from the fractionator, subjecting a portion thereof to condensation, collecting the resulting distillate andv gas, subjecting the remainder of said uncondensed vapors to ieheating in a separate heating coil under conditionsof high temperature and super-atmospheric pressure, suitable to effect a substantial improvement lin their anti-knock value, and introducing the highly heated vapors into the coking zone to 5o commingle with the residual material therein and assist its coking and devolatillzation.

It will be understood that many modifications of the speciiic embodimentpabov'e described may 'oe employed without departing from the scope of the present invention. For example, the reaction chamber may, when desired, be dispensed with and the heated hydrocarbon oil introduced from the heating coil directly into the reduced pressure coking zone. This type of operation is especially adaptable tothe treatment of relatively heavy charging stocks such as residual oils, heavy crudes and the like, but may also be' utilized in the treatment of lighter charging stocks by employing additional conversion time in the heating coil to compensate for the conversion time in the reaction chamberlost by its elimination. Another possible modification involves the use of a portion of the distillate from the receiverv of the system as the material subjected to reforming and utilized as the heat carrying medium for the coking operation instead of the vaporous product from the fractionator, prior to its condensation. Use of the product in vaporous state may eiect some saving in heating, comparable in quantity to -the heat which would be extracted from this product by its condensation. Use offeatures of the present invention and in which the process of the invention may be practiced. Raw oil `charging stock for the system maybe supplied through line I and valve 2 to pump 3 from which it may be fed through lin'e 4, valve 5 and line 6 directly to heating coil 1 or it-may pass, allor in part, from line 4 through line 8 and valve- 9 to preheating coil I 0 which is located within fractionator Il. The raw oil supplied to coil III `is preheated by indirect contact with the heated vaporous conversion products in this zone and may pass from the coil in preheated state through line I2 and valve :I3 into line 6 and thence to heating coil 1. It will be understood that other well known means of preheating; the raw oil may be employed, although not shown in the drawing, and a portion or all of the raw oil may be introduced directly into fractionator Il, by well known means not illustrated, to com- I mingle with the vapors, assist their fractionation and be returned from the fractionator, together with reux condensate'from this zone, by means of line I3', valve I4, pump I5, 4line I6, valve I1 and line E, to heating coil 1.

` form of furnace I8 which supplies the heat required to bring the oil to the desired conversion temperature under theA desired superatmospheric pressure. The heated oilis discharged from heating coil1 through line I9 and may pass directly through line 20 and valve 2| into coking chamber/22, through line 23, and valve 24, or into coking chamber 22 through line 23' and l0 valve 24'. However, the preferred method of operation, in most cases, is tov pass the hot conversion/ products from heating coil 1 through reaction chamber 25, prior to their introduction into the coking zone, in which case the heated oil passes from line I9 through line 26 and valve 21 .into reaction chamber 25 while both liquid and vaporous products are withdrawn. from the lower portion of chamber 25 through line 28 and valve 29 into line 20 and thence to the coking zone, as just` described. Chamber 25, when utilized, is

preferably maintained at substantial superatmospheric pressure which may be equalized with or somewhat reduced relative to that employed at the outlet from the heating coil. By means of introducing the heated oil from heating coil 1 into the upper portion of the chamber 25 and withdrawing the products from the lower portion of the reaction chamber, the vaporous products. which gravitate to the bottom of the chamber more slowly than the heavier liquid products, are

subjected to a longer conversion time than they residual liquid in chamber 25. Any other well known method of operation may be employed in chamber 25 without departing from the scope of the invention. Chambers 22 and 22 are similar coking chambers preferably operated at substantially reduced pressure relative to that employed in the heating coil (and in the reaction chamber, when used).

. of a plurality of such zones may be utilized for the coking operation; a plurality being preferred to provide additional space for the deposition of coke and permit prolonged operation of the process. When a plurality of coking chambers are employed they may be operated either a1- ternately pr simultaneously. Chambers 22 and 22' are/provided respectively, with lines Il and 30', controlled respectivelyby valves 3| and 3l', which may serve as drain lines and also as means for the introduction of steam or water to hasten -cooling of the chambers after their operation has been discontinued.

Vaporous products' are removed from chamber 22 through line 32 and valve 33 and from chamber 22' through line 32 and valve 33'. The vaporous productsl of the system pass from the coking zone through line 34 to fractionation in fractionator I I. 'I'he heavy components of the vapors are condensed within fractionator II to be supplied therefrom, as already described, to heating coil 1 for further conversion. vaporous products remaining uncondensed in Yi'raotionator II are withdrawn from its upper portion through 65 line 35 and a portion or all of this material passes through valve 36 to condensation ndcooling in condenser 31. Condensed distillate and uncondensable gas passes from condenser 31 through linen and valve 39 to be collected in receiver 40. Uncondensable gas may be released from the receiver through line 4I and valve 42. Distillate may be withdrawn from the receivei to storage or to any desired further treatment lthrough line 43 and valve 44. A portion of the 1I uncondensed. vapors may be diverted from line It willbe understood that one or any number Heating coil 1 is located within any suitable 35 through line 45 and valve 45 to pump or compressor 41 and may be fed therefrom through line 4l, valve .49 and line 5I to heating coil 5I. In a similar manner a portion of the distillate from receiver 40 may, when desired, be withdrawn through line 52and valve 53 to pump 54 from which it may be fed through ,une ss, valve sa and line Sltoheating coil 5I."" f

Heating coil 5I is located in a suitable furnace 51 of any desired form and the oil supplied thereto is heated to a relatively high temperature, preferably at substantial superatmospheric pressure, and is thence discharged through line 5l and may pass through line 59' and valve 60 into coking chamber 22 and/or through line 59 and valve 60 into coking chamber 22, commingling in the coking z one with the residual material therein and assisting its coking and devolatilization.

'Ihe heating coil wherein the raw oil charging stock and reflux condensate are treated preferably utilizes a pressure ranging from 100 to 500 pounds, or thereabouts, per square inch with an outlet temperature ranging, for example, from 850 to 950 F. or thereabouts. Substantially this same range lof pressures is preferably employed in the reaction chamber. A reduced pressure ranging, for example, from 100 pounds per square inch down to substantially atmospheric pressure is employed in the coking zone and may be sub- '1 stantially equalized in the succeeding fractioni ating, condensing and collecting portions of the system. A conversion temperature ranging, -for example, from 900 to 1100 F. may be employed in the heating element wherein the distillate or vaporous product is subjected to reforming, with a pressure in thisA zoneiranging, for example, from 200 tov 800 pounds, or thereabouts, per square inch.

As' a specific example of the operation of the process of the invention, a 30 A. P. I. gravity Mid-Continent topped crude is the charging stock foi' the system. The raw oil and reflux condensate are subjected to a conversion temperature of approximately 910 F. at a superatmospheric pressure vof about 250 pounds per square inch. A pressure of about 50 pounds per square inch is employed in the coking zone and vapors from-the fractionator are reheated to a temperature of approximately 980 F., at a superatmospheric pressure of about 400 pounds per square inch, and are then introduced into the coking zone. This operation may yield aboutof motor fuel having an 'anti-knock value equivalent to an octane number of approximately '78 and in addition there may be recovered, per barrel ofcharging stock, about 65 pounds of petroleum coke having avolatile content of less than 5% and about 1000 cubic feet of uncondensable gas.

I claim as my invention:

1. In a conversion process wherein hydrocar v bon oil heavier than gasoline is. subjected to cracking conditions of temperature and pressure in a heating coil and subsequently separated into vapors and unvaporized oil, and the unvaporized oil distilled to coke in a coking zone; the method which comprises fractionating said lvapors in a fractionating zone to separate fractions heavier than gasoline from the gasoline boiling hydrocarbons, passing a portion of the gasoline boiling hydrocarbons in vapor form from the fractionating e to a iinal condenser and condensing the same t erein, collecting this condensed portion of the gasoline` boiling hydro' T5 'gcarbons' as a product of the process, passing remaining portion of heating coil maintained at higher temperaturel than the nrst-named coil and heating the same therein sumciently to enhance the yanti-knock value thereof, and'discharging the heated products from the second coil into contact with the unvaporized oil in the coking zone to assist the coking of the unvaporized oil therein.

2. In a conversion process wherein hydrocarbon oil heavier than gasoline is subjected to cracking conditions of temperature and pressure in a heating coil and subsequently' separated into vapors and unvaporized oil, and the unvaporized oil distilled to coke in a coking zone; the method which comprises fractionating said vapors in a fractionating zone to separate the gasoline as vapor from the heavier insufficiently cracked fractions as condensate, removing the gasoline in vapor form from the fractionating zone and finally condensing and collecting a portion there- 'of as a product of the process, passing the remaining portion of vthe .gasoline vapors, without prior condensation thereof, to a second heating coil maintained at higher temperature than the first-named coil and heating the sam'e therein suiciently to enhance the anti-knock value thereof, and discharging the heated products from the second coil into contact with the lunvaporized oil in the coking zone to assist the cokingof the unvaporized oil therein.

3. In a conversion process wherein hydrocarbon oil heavier 'than gasoline is subjected to cracking conditions of temperature and pressure in aheating coil and the 'heated oil subsequently flh' distilled by pressure reduction in a reduced pressure zone; the method which comprises fractionating the vapors from the reduced pressure,

zone in a fractionating zone to Separate fractions heavier than gasoline from the gasoline boiling hydrocarbons, passing a portion of the gasoline boiling hydrocarbons in vapor form from the fractionating zone to a final condenser and condensing the same therein, collecting this condensed portion of the gasoline boiling hydrocarbons as a product of the process, passing the bon remaining portion o f the gasoline boiling hydrocarbonsl from the fractionating zone to a second heating `coil maintained at higher temperature than the first-named coll and heating the same therein suiilciently to enhance the' anti-knock value thereof, and discharging the heated products from the second coil into contactwith the oil in the reduced pressure zone to assist the distillation thereof.

4. In a conversion process wherein hydrocarcrackingconditions of temperature and pressure in a heating coil and the heatedv oil subsequently ash distilled by pressure reduction in a reduced pressure zone ;v the method which comprises fractionating -the vapors from thereduced pressure zone in a fractionating zone to separate the gasoline as vapor from the heavier insulciently cracked fractionsas condensate, removing the gasoline in vaporform from, the fractionating z one and finally condensing and collecting a portion thereof as a product of the process, passing the remainingl portion of the gasoline vapors, without prior condensationthereof, to a second heating coil'maintained at higher temperature than the first-named coil land heating'the same therein sumcientlyto enhance the anti-knock `value thereof, and discharging' the heated prodoil heavier than gasoline is subjected to ucts from the second-coll into contact with the oil in the reduced pressure zone to assist the distillation thereof.

5. In a conversion process wherein hydrocar-` bon oil 'heavier than gasoline is subjected to cracking conditions of temperature and pressure in a crackingzone, unvaporized portions of the oil ash distilled by pressure reduction in a reduced pressure zone, and vaporous portions thereof fractionated in a fractionating zone to separate fractions heavier than gasoline from gasoline boiling hydrocarbons; the improvement which comprises passing a portion of the gasoline boiling hydrocarbons in vapor form from the fractionating zone to a'ilnal condenser and condensing and collecting the same as a product of the process, passing the remaining portion of the gasoline boiling hydrocarbons from the fractionating zone through a second cracking zone maintained at higher temperature than the firstnamed cracking zone and heating the same therein sumciently to enhance the anti-knock value thereof, and discharging the heated products from said second zone into the reduced pressure zone to assist the distillation of the unvafractionating zone to a nnal condenser and condensing and .collecting the same as a product of the process, passing the remaining portion of the gasoline boiling hydrocarbons from the fractionating zone through a second cracking zone maintained athigher temperature than the firstnamed cracking zone and heatingl the same therein sufliciently to enhance the anti-knock value thereof, and discharging the heated-prod ucts from` said second zone into the vreduced pressure lzone to assist 4the distillation of the unvaporized oil therein, the quantity of hydrocarbons passed fromthe fractionating zone to the second cracking zone being suillclent, after the heating thereof in'said second zone, to distil the unvaporized oil to coke in the reduced pressure zone. Y

7. In arconversion process wherein hydrocar- .bon oil heavier than gasoline is Asubjected to cracking conditions of temperature and pressure in a heating coil and the heated oil 'subsequently ash distilled by pressure reduction in a reduced pressure, zone; the method^which comprisesfractionating the vapors from the reduced pressure4 zone in-a fractionating zone to separate fractions heavier than gasoline from the gasoline boiling hydrocarbons, passing a portion of the gasoline boiling hydrocarbons in vapor form from the fractionating zone to'a. final condenser andcondensing the same therein, collecting this condensed portion of the gasoline boiling hydrocarbons as a product of the process, passing the remaining portion of the gasoline boiling hydro- -carbons from the fractionating -zone to a second heating coil maintained at higher temperature than the first-named colland heating the same therein sufliciently to enhance the anti-knock value` thereof, and discharging the heated prod-.

o cracking conditions of temperatm-e and pressure in a heating coil and the heated oil subsequently iiash distilled by pressure reduction in a reduced pressure zone; the method which -comprises fractlonating the vapors from 'the reduced pres- 15 sure zone in a fractionating zone to` separate the gasoline as vapor from the heavier insuiiiciently cracked fractions as condensate, removing the gasoline in -vapor-form from the fractionating zone and finally condensing and collecting a portion thereof as a product of the process, passing the remaining portion of the gasoline vapors,

without prior condensation thereof, to a second heating coil maintained at higher temperature than the first-named coil and heating the same therein suillciently to enhance the anti-knock value thereof, and discharging the heated products from the second coil into contact with the oil in the reduced pressure zone to assist the distillation thereof, said remainingportion of the gasoline vaporsv being suicient, after the heating thereof in said second coil, to distil the oil in the reduced pressure zone to coke.

JEAN DELATI'RE SEGUY.

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