US1843664A - Process for cracking hydrocarbons - Google Patents

Description

Feb. 2, 1932. G. EGLOFF 1,343,664

PROCESS FOR ,CRACK ING HYDROQARBONS Filed Dec. 4, 1919 Rerun stills Tran spor'ii line forRDBoi ms,

z Mix-i,

chum er ess in which-the hot Patented Feb. 2,1932.

" UNITED STAT S PATENT OFFICE A CORPORATION OF SOUTH DAKOTA rnocliss ron cnacxme mnnocmons Application and December 4, 1919. Serial no. 342404.

- M invention relates to a process for treat ing ydrocarbons and larly to 'a process for maimng in pressure utilizing the heat re'-.

bined, with the raw ()1 process in which the-pressure distillate bot-v toms, from the neighboring re-run stills, are

collected in a transporting line while they are in a heated condition, .as when they come direct from the distilling zone and are pumped back into the raw oil charge about -to enter the cracking zone of a still, thereby transferring a portion of their heat to the raw 'oil and being again subjected 'with the raw oil to treatment in the crackin tubes; to prov vide a process in which, besi es the feature of utilizing to a greater extent theheat generated, the hot pressure distillate bottoms are more completely cracked by being retreated in the same or a related still as they are com- I bined with the raw .oil charge of said still; to provide a novel type of apparatus for car-- rying out this process and in general to'provide a process and apparatus of the character referredto.-

' In thedrawing I have shown a side elevation of a still, partly in section and with parts broken away, showing the double pump arrangement combining the pressure distillate bottoms from neighboring rerun the raw oil.

' Referring more particularly to the drawiug, within the still 1, consisting of "a furnace portion 2 heated by" suitable burner 3, are mounted cracking tubes 4 situated above the furnace and receiving the raw oil chargethrough charging pipe- 5 and mixing chambar 6. The charging pipe is controlled by .valve 7 and is provided with a suitable pump refers more particudistillate bottoms to wraisethe temperature of the fresh incom ng stilland there com'- charge; to provide a charging pipe 26a. Theoil vaplors after being cracked in the tubes 4 .rise t rough pipe 5.1nto a vertical tube considered as a whole 8, which con- .sists in a dephlegmator or separator ortion 9 an a lower expansion or vapor c amber 10. The oil vapors rislng 1nto the expansion chamber are distributed therein by a baflle cone 11. .The heavier residue is drawn off from the bottom of the vapor chamber through a pipe 12 controlled by valve 13.

ous'r'av senor-r, or mnnrnnnnucn msasi sis stones. :ro umvnnsn. ornrnon- I UCTS COIPA'NY, OF CHICAGO, ILLINOIS,

The l1ghter vapors rising in the separator portlonv are directed through the gooseneck 14 to the pipe coil 15 in the water condenser 16. This condenser is mounted upon any suitable standard 17. The distillate from the condenser passes to the receiver 18 through pipe 19. A drawolf 20 controlled by valve 21 provides a means of taking oif the distillate from time to time. A suitable gauge 22 of a common type is mounted on the side of the receiver and denotes the quantity of distillate in the receiver. Apressure gauge 23 registers the pressure upon the system.

A pressure valve 24, together with the drawofi valve 21 and the valve 13 in the residuum line provide a means of regulating the pressure in the system. My inventionconsists in introducing pressure distillates'or pressure distillate bottoms from any source, preferably neighboring stills, while the'bottonis' are'yet' in a heated condition and before they are allowed to cool or before they have been passed through water of aerial coolers, through a charging pipe 25 a suitable charging pump 26 and a pipe lirie 27, which-charges the pressure distillate bottoms directly tothe charging line of'the still through the mixing chamber 6. The

valve. Th introduction of these pressure distillate bottoms while in a heated condi-.

27 may lie-regulated by the valve 28 and the amount of distillate introduced into 'the'system controlled by this tion,-besides theadvantage of retreating said? distillate bottoms, tends to transfer the heat thereof to the raw oil charge.

It will be seen that this will greatlyecono- 1 mize the heat of the still, into which the pressure distillate bottoms are charged. A reflux line 29 is tapped into the lower portion 2 I eeaeee of the separating chamber of the dephlegmator to direct the reflux condensate from the dephlegmatoi' back to the charging line 5 through the mixin chamber 6. This reflux 5 line 29 is controlled y a valve 30.

' The following illustrative run may be given: Taking gas oil from the mid-continent field, such as Kansas or Oklahoma yield, say of 32 Baum; this gas oil is charged into m the cracking zone and is heated to a temperature of from 750 to 900 F. A suitable pressure say, from 50 to 150 lbs. is maintained on the system during the entire operation. Gas oil treated in this manner yields 5 from 30% to 40% of gasoline or other low boiling point hydrocarbons havinganend point of 400 F. e Whereas, before utilizing the hot pressure distillate bottoms,.by charging same mixed at with thechargingoil into the cracking still, I there wasconsumed' per gallon of gasoline made approximately 95,000 E. t. u.; after adding the hot pressure distillate bottoms the 'B. t. 11 value per gallonof gasoline dropped 25 to 87,000. In carrying out the foregoing run, I utilize from to hot pressure distillate bottoms, mixed with the gas oil, although fa higher percentage of the distillate bottoms may be used. These hot) distillate bottoms impart heat to'the gas oil and serve to materially lower the quantity of fuel, as well as the time required to crack the oil. By the term distillate bottoms, it is meant that I utilize that portion of distillate resulting from the cracking of oil which has accumulated in the bottom of a re-run still, and which has a boiling point above 450 F. In other words, by practicing my process a fuel saving of from five to ten percent in 40 cost per gallon of gasoline may be efiected.

ll claim as my invention: A process for converting relatively heavy into relatively lighter hydrocarbon oilscomprising initially subjecting the oil to crack-' mg conditions of temperature and pressure while flowing throu h a heating coil disposed within a furnace, elivering the heated oil from said coil to an enlarged reaction zone from which no unvaporized oil is permitted 5a to return to said'heating coil, subjecting vapors issuing from said enlarged reaction zone to reflux condensation, simultaneously introducing to a mixing chamber hot reflux condensate separated from the vapors under- .55 going reflux condensation, hot pressure distillate bottoms and a quantity of fresh charging oil for the process, and supplying the commingled oils directly from said mixing chamberto said conversion unit.

at eus'rav Esters.

Images