US1887083A - Process and apparatus for cracking oil - Google Patents

Description

Nov. 8, 1932. G. EGLOFF PROCESS AND APPARATUS FOR CRACKING OIL Original Filed Dec. 9, 1920 Patented Nov. 1932 UNITED STATES PATENT OFFICE GUSTAV EGLOFF, O1 CHICAGO, ILLINOIS, ASSIGNOR TO UNIVERSAL OIL PRODUCTS COM- PANY, OF CHICAGO, ILLINOIS, A CORPORATION OF SOUTH DAKOTA PROCESS AND APPARATUS FOR CRACKING OIL Application filed December 9, 1920, Serial No. 429,318. Renewed November 23, 1928.

This invention relates to improvements in process for cracking oil, and refers more particularly to the production of a blended light oil constituent produced by the cracking of relatively heavy hydrocarbons of different characteristics.

The gasolene sold now in the market obtained from the cracking process is generally a blended product, which blending has to be done after the pressure distillate has been produced and refined. The present invention tends to produce such a blended product as part of the cracking operation. By means of the present invention, the light oil constituents may be produced from say fuel oil and from lighter oil constituents, say gas oil or kerosene. These difl'erent oil bodies are subjected to predetermined and diflerential conditions of pressure and temperature, as it is well known to those skilled in the art that they do not crack under like conditions. For example, in carrying out the process, a Kansas gas 011 may be cracked in one portion of the apparatus, and a Kansas fuel oil in another portion of the apparatus.

I have referred to the cracking of diflerent cuts from the same petroleum crude, but the invention also relates to the cracking in the same apparatus, under diiferent conditions, different petroleum, as for example, a California petroleum, or cut therefrom, and a Kansas petroleum, or cut therefrom. The different oils are treated entirely independently except that they are treated in the same apparatus, and are blended only as vapors as they enter the reflux condenser. In this way, the heavy residues are never mixed, but may be drawn oif separately and otherwise treated or disposed of.

The objects sought to be obtained are to get a blended final product having the desired percentage of say constituents boiling below 150.51 R, the desired percentage boiling below 200 F., 300 F. and 400 F. It will be understood that these figures are merely illustrative.

In the drawing, the single figure designates a view partly in side elevation and partly in vertical section of my improved 0 apparatus.

Referring to the drawing, 1 designates a furnace, provided with combustion chambers 2and 3, separated by a foraminated bridge Wall 4. The combustion chambers are provided with stack 5, and each combustion chamber with a burner 6. In the lower combustion chamber is mounted a heating coil 7, as for example a continuous coil of two to six-inch pipe, while in the upper chamber is mounted a similar heating coil 8. The heating coil 7 is connected to feed pump 9, by means of feed line 10, having throttle valve 11. This pump 9 may be connected. to, for example, raw fuel oil of say 23 degrees Baum. The inlet side of the coil 8 is connected by feed line 12, having throttle valve 12, to a feed pump 13, connected to raw oil supply, as for example gas oil of say 33 degrees Baum. The delivery side of the coil 7 is connected by transfer line 14, having throttle valve 15, to an expansion chamber 16, located outside the fire zone. This expansion chamber 16 is provided with a residue draw off line 17, having throttle valve 18. The delivery end of the coil 8 is connected by transfer line 19 having throttle valve 20 to an expansion chamber 21 also located outside the fire zone. This expansion chamber 21 is provided with residue draw ofl' pipe 22, having throttle valve 23. The vapor space in expansion chamber 16 is connected by vapor pipe 24, having throttle valve 25, to the dephlegmator 26. Similarly,

the vapor space of the expansion chamber 21 is connected by vapor pipe 27, having throttle valve 28, to the dephlegmator 26. This dephlegmator 26 is provided with a series of alternately disposed baflle members 29, and at its upper end is provided with a vapor outlet pipe 30, having throttle valve 31, which pipe 30 leads to condenser coil 32, seated in condenser box 33. The lower end of the coil 32 is connected by pipe 34, having throttle valve 35, to the top of receiver 36. This receiver 36 ,is provided with a liquid level gauge 37, liquid draw oif pipe 38, controlled by throttle valve 39, and gas outlet pipe 40, controlled by throttle valve 41. Various parts of the system are provided with pressure gauges 42 and pyrometers not shown.

The reflux condensate is drawn off from the bottom of the dephlegmator through pipe 43. This pipe 43 is provided with a branch 44, having throttle valve 45, leading to the pump 13. It also is provided with a branch 46, having throttle valve 47, leading to the pump 9. It also has a branch 48, having throttle valve 49, leading to any suitable re ceptacle (not shown). The arrangement is such that the reflux condensate may be. returned to either heating coil for further treatment, or can be diverted elsewhere.

The process may be carried out in this apparatus as follows:

Kansas fuel oil of say 23 degrees Baum may be fed continuously to the lower heating coil, subjected to a temperature of 680 degrees F and a pressure of 130 pounds. Simultaneously, Kansas gas oil of say 33 degrees Baum may be fed through the other heating coil, there heated to a temperature of say 750 degrees F. and a pressure of say 160 pounds. The same pressure that is maintained on each heating coil may be maintained on its corresponding expansion or vapor chamber. A pressure of pounds may be maintained 011 the dephlegmator and the remainder of the apparatus, or a differential pressure may be maintained between the dephlegmator and condenser and receiver. The reflux condensate may be returned to either coil and will continuously be returned to that coil wherein the oil is being subjected to conditions best suited to the further crack ing of the particular type of reflux condensate being formed. For example if the reflux condensate more closely resembles the fuel oil it had better be returned to the fuel oil heating coil. Contrariwise, to the gas oil heating coil.

I have referred to cracking of fuel oil and gas oil, instead of diflerent cuts of the same petroleum. Different petroleums may be treated, as for example California oil, crude oil. or California gas oil and fuel oil in one coil, and Oklahoma fuel oil or Oklahoma; gas oil in another coil. Also, instead of treating gas oil kerosene may be treated, or a mixture of gasolene and kerosene. The quantity of oil fed through each coil will depend upon the desired end point product desired, as well as the desired distillation curve and the resultant gasolene or pressure distillate. It will also depend upon the character of the oil available for treatment.

I claim as my invention:

1. A process for producing a cracked blended low boiling point oil, consisting in simultaneously subjecting a gas oil and a fuel oil to independent cracking treatments under relatively higher and lower conditions of temperature and pressure respectively, in completely preventing commingling of liquid constituents of said oils, in uniting the vapors evolved from the oils while at a high temperature, in subjecting the united vapors to dephlegmating and condensing actions, and in uniting reflux condensate separated from the vapors during the dephlegmating action with the gas oil undergoing treatment in the process.

2. An apparatus for cracking oil comprising a plurality of heating coils arranged in parallel, a separate enlarged chamber connected to each coil, dephlegmating means, means for delivering vapors from said enlarged chambers to said dephlegmating means, means for sepa 'ately supplying oil from independent sources to said heating coils and means for selectively returning reflux condensate from said dephlegmating means-to said heating coils.

3. An apparatus for cracking oil comprising a plurality of heating coils arranged in parallel, a separate enlarged chamber connected to each. coil, dephlcgmating means, means for delivering vapors from said enlarged chambers to said dephlegmating means, means for separately supplying oil from independent sources to said heating coils and means for selectively returning reflux condensate from said dephlegmating means to said heating coils, and means for controlling the quantity of reflux condensate returned for retreatment relative to the amount of reflux condensate formed in the process.

4. A hydrocarbon oil cracking process which comprises passing through a heating zone a charging oil from a source extraneous to the cracking process and subjecting the same therein to cracking conditions of temperature and pressure. simultaneously passing through a second heating zone a second charging oil also from a source extraneous to the cracking process and of lower boiling point than the first mentioned charging oil, subjecting said second charging oil in said second heating zone to a higher cracking temperature under pressure than that. to which the first mentioned charging oil is sub jected, passing the heated oil constituents from the first mentioned heating zone to an enlarged zone, passing the heated oil constituents from said second heating zone to a second enlarged zone independent of the first mentioned enlarged zone, uniting vapors issuing from both said enlarged zones, subjecting the combined vapors to dephlegmation. and condensing the dephlegmated vapors.

5. A hydrocarbon oil cracking process which comprises passing through a heating zone a charging oil from a source extraneous to the cracking process and subjecting the same therein to cracking conditions of temperature and pressure, simultaneously passing through a second heating zone a second said second heating zone to a second enlarged zone independent of the first mentioned en larged zone, uniting vapors issuing from both said enlarged zones, subjecting the combined vapors to dephlegmation, condensing the dephlegmated vapors, and returning reflux condensate formed during the dcphlegmation to one of said heating'zones for retreatm'ent.

6. A hydrocarbon oil cracking process which comprises passing through a heating zone a charging oil from a source extraneous to the cracking process and subjecting the same therein to cracking conditions of temperature and pressure, simultaneously passing through a second heating zone a second charging oil also from a source extraneous to the cracking process and of lower boiling point than the first mentioned charging oil,

subjecting said second charging oil in said second heating zone to a higher cracking temperature under pressure than that to which the first mentioned charging oil is subject ed, passing the heated oil constituents from the first mentioned heating zone to an enlarged zone, passing the heated oil constituents from said second heating zone to a second enlarged zone independent of the first mentioned enlarged zone, uniting vapors is suing from both said enlarged zones, subjecting the combined vapors to dephlegmation, condensing the dephlegmated vapors, andreturning reflux condensate formed during the dephlegmation to said second heating zone for retreatment with said second charging oil.

GUSTAV EGLOFF.

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