US1990868A - Process for hydrocarbon oil conversion - Google Patents

Description

Feb. 12, 1935. J. B. HEID PROCESS FOR HYDROCARBON OIL CONVERSION Filed April 8, 1927 \wfiw a N a mi m w w. i

mm4%%i% 4 Patented Feb. 12 1935 I UNITED STATES PATENT OFFICE PROCESS FOR HYDROCARBON OIL CONVERSION- .Jacoh Benjamin Heid, Chicago, Ill., assignor to Umversal Oil Products Company, Chicago, 11 a corporation of South Dakota Application April's, 1927, Serial No. 182,039%

3 Claims. (Cl. 19648) This invention relates to improvementsinproctemperature at the outlet of said coil 6. From ess and apparatus for hydrocarbon oil conversion, said closed coil 6 the preheated oil passes out and refers more particularly to those types of through the line 8 controlled by'the valve 9 processes in which the oil is converted under into amanifold header 10, to which are connected pressure and heat into low boiling point hydroseveral branch lines 11, controlled by valves 12, 5

carbons, while the heat spent for the conversion and so positioned that each branch 11 leads to is recovered in other parts of the process and evaporator 13, being connected therewith'at vautilized for removing from crude petroleum or rious points over the height of said evaporator. other charging stock, the lighter valuable frac- In this manner, by controlling the various valves tions naturally contained therein, or other light 12 on said lines'll, it is possible to'controlthe' 0 fractions, after which the oil, from which said point at which the preheated oil enters the evaplight fractions have been removed, is converted in orator. Evaporator 13 may comprise fractionathe process. The characteristics of the light tion means, such as plates 14, or other type, fractions removed from the crude oil before the so that when the preheated oil enters the column 15 topped crude or residue is subjected to conversion, 13 at the selected point thereof the fractions, 5 are controlled either by the state of the market, which it is desired to remove from the oil before or by the undesirability of passing through the passing the latter through the cracking zone, cracking zone fractions which, by their refractory separate at the same time that they are subjectcharacteristics to cracking would decrease the ed to fractionation, thereby producing from the capacity and efficiency of the cracking process. top of said column 13 a finished product. Said 0 Other features of the invention will appear more finished product, in the form of vapor, passes off clearly from the following description, and from the top of column 13 through line 15, controlled the attached drawing, in which the single figure by valve 16, thence into a condenser 17,'and from is a diagrammatic view, partly in section and there through line 18, controlled by valve 19, it is partly in elevation, of an apparatus suited to directed to storage means not shown. 25 carry out the process. To assist in the fractionation of the oil in the It is understood that the process can be'carried evaporator 13, a cooling medium such as gasoline out in a number of types of apparatus which or the like, can be injected in the top of the can be easily designed by any one skilled in the evaporator through line 20, controlled by valve art, and while I have shown in the drawing and 21,111 which are interposed pump 22 and valve 30 described hereafter a suitable type of apparatus, 23, through which said cooling medium isintro- I-do not wish in any way'to be' limited by the duced into a spray coil, or other injecting means, type described. such'as shown at 24.

Referring to the drawing: It may be desirable to assist the separation of Theoil which contains the natural light fracthe lighter fractions from the 'heavier'portions 35 tions which it is desirable to remove before passof the oil by'injecting into evaporator 13, prefering the Oil through the ac ng Zone, for i ably at the bottom thereof, steam or other hot stance,- crude oil, from-which it is desirable to gas, such as for instance, non-condensible gases remove gasoline kerosene, or both, 01 a topped produced in the process after they have been 40 Crude in w ch the l htest gasoline fractions heated to the proper temperature, and this can 40 hav b en r v d, but in w ich the h avi r be effected through line 25 controlled by valve 26. naphtha, or the kerosene, have been left, is It may be here noted that while the pressure pumped through the line 1, controlled by valve can be equalized on the oil passing through the 2, through pump 3, controlled by valve 4 and preheatingcoil 6 and undergoingtopping or sepainto line 5. From line 5 the oil is passed through ration in the evaporator 13, it may also be de-' a heat exchanging closed coil 6, positionedin the sirable to preheat the oil in the coil 6 under a dephlegmator 7 of the cracking zone, which will pressure higher than that maintained on evapobe-described later. The coil 6 may be positioned rator 13. If the operation is carried outwith at Var u heights the ph 'gmator, and may this latter method, separation of the lighter fracextend throughout t height h r maybe tions from the oil through evaporator 13 is as lim t d t the pp or w dd portion sisted by flashing or evaporation due to reduction as desired, in such a manner that the heat transof pressure. j 7 fer from the vapors undergoing dephlegmation'in The heavier fractions of the charging stock the dephlegmator 7, to the cold oil passing which have separated from the lighter fractions through the coil 6 brings said oil to the desired in evaporator 13, collect in the bottom of the evaporator and are withdrawn from the bottom thereof through line 2'7, controlled by valve 28,

and passed through line 29, controlled by valve 30. They are then passed through pump 31, line 32, controlled by valve 33, to the heating coil 34, positioned in furnace of conventional type, which may be of any design found suitable. This furnace is heated by burners such as shown at- "35A. By passing through heating coil 34 the oil is brought to the proper temperature for conversion under suitable pressure, and the heated oil from such coil is discharged through transfer line 36, controlled by valve 37, into a reaction chamber 38, which has been shown of the vertical type, but which may be of any other type. This chamber is provided-with suitable cleaning manholes 39. In said reaction chamber the heated oil undergoes reaction and the products of reaction separate into vapors, and into both. liquid, solid residues, or solid residue alone. The liquid residue, if any, is discharged preferably in a continuous I manner from reaction chamber 38-,

I through residue drawoffs 40, controlled by valves 41, from where the residuum can be passed to means are so arranged that they provide for the room necessary to mount the heat exchanging coil 6 above described.

In the dephlegrnator 7 vapors undergo fractionation in the usual manner, assisted by the cooling effected by the oil passed through coil 6 The fractionation may be assisted also by means of an additional cooling agent introduced into.

the upper part of the, dephlegmator, suchas through line ,45, controlled by valve 46, and spray coil 47.. Ifhis cooling" agent may be a portion of the pressure distillate produced in the process,

or any other agent such as gasoline, or the like- Vapors 'which'have not been condensed the dephlegmator 7 pass off the' top thereof; through.

line 48 controlled by valve 49, through condenser 50, and thence through line 51, controlled by valve 52, into receiver 53, whichis provided with the, gas release line 54,1controlled by valve 55, and. with a distillate drawoif 56, controlledby valve 57. I V

According to the characteristics of the cracked product from-the cracking zone, and withdrawn in the form of vapor at the top of dephlegmator '7, it may be desirableto mix the said cracked product with the fractionsv originally removed from the oil in evaporator 13, and this can be effected, for instance, by means of connections such asby-pass 58, controlled by valve 59, be-- tween the outlet of the condenser 17 and the outlet line from condenser 50 to receiver 53.

. As ,a-further feature of'my invention, it may be desirable also to submit the vapors leaving the top ofdephlegmator '7 to a secondary fractionation so as to obtain cracked products similar in characteristics to the light products removed. originally from the crude oil, or other cha gi stock in. evaporator 13, and it is to be understood that tions of the original crude oil through lines 27; 29, 32 and pump 31, as heretofore described. In this case,'if,-as' has been heretofore mentioned,

the pressure on evaporator 13 is lower than that on the preheating coil 6, and lower also than that maintained ondephlegamator 7, said pressure may be reduced on the vapors from said dephlegmator by means of valve 61. It may be herenoted that the pressure which can be maintained' onthe oil passingthrough the coil 6- may be different from that maintained on the vapors undergoing fractionation in dephlegmaton 7, and. I

that these pressures will be set according to the characteristics of the oil treated, and of the products desired, and valves 9, 61 and other valves and pumps shown, permit of controlling the pressures, as desired. r

Returning to dephlegmator, 7, the reflux condensate which has been formed and which accumulates at the bottom thereof, is Withdrawn,

through line 62, controlled by valve 63, and passed through pump 64 and line 65 controlled by valve 66, where said reflux condensate mixes with the oil directed to the heating tubes through line 32. If desirable, the pump 64 may be 'by-passed by means of line 67, controlled by valve 68, by proper regulation of said valve, and of valves 63 and 66.

For the treatment of certainoils under certain pressures, the reflux condensate formed in the dephlegmator 7 may contain,'on account of, the solubility of the fractions at the pressure employed, an objectionable amount of light frac-; tions, the presence of which inthe reflux condensate tends to reduce the capacity and theefiiciency of the. cracking zone. If, is prohibitive it may be desirable to separatesuchrlight fractions from the bulk of the reflux-condensate.

and this may be done, for instanceby divertingthe reflux condensate from line 62 through branch-line 69, controlled by valve 'lti,v which can be used to control the pressure, into the line; 3, through which, as heretofore described the'ptcheated raw oil is passed, in. the first cycle of operation, from. the preheating coil 6 tothe evaporator 13. this manner, the reflux condon i sate undergoes separation in said evaporator 13,.

and can be relieved thereby of its lightest frac tions, and the non-vaporized portion of the -re-' flux con-densate combined with the non-vaporized portion of the crude petroleum, or other chars: ing stock is directed from said evaporator 13,

through line 29, pump 31, line 32 into the cracking coil 34, as heretofore described:

- The temperature in the heating coil 341s regu lated incorrelation with the pressure maintained in said ;coil,; and it mayvary from. say

'tained between the various zones of the plant from heating coil 34 to receiver 53. Furthermore, as has been pointed out throughout this description, differential pressures may be maintained between the fractionating zone 7, preheating coil 6 and evaporating zone 13, by means of the various valves and pumps shown; so that, by proper regulation of the pressures and temperatures used throughout the system, the maximum efliciency and capacity may be maintained during the separation in evaporator 13, as well as during the cracking and fractionation in the cracking zone.

.I claim as my invention:

1. A method of treating hydrocarbon oil which comprises subjecting oil to cracking conditions in a cracking zone, passing resultant vapors to a dephlegmator, flowing charging oil for the cracking zone in heat interchange relation but out of contact with the vapors in the dephlegmator, uniting the charging oil subsequent to its passage in heat interchange relation with the vapors in the dephlegmator with reflux condensate separated from the vapors in the dephlegmator, passing the commingled oil and reflux condensate to an evaporating zone and vaporizing the more volatile constituents therein, removing and condensing said more volatile constituents, removing vaporized fractions from said dephlegmator and condensing the same, and passing unvaporized oil from said evaporating zone to said cracking zone for treatment therein.

2. In the art of hydrocarbon oil conversion, steps which comprise subjecting charging stock to a preheating, non-cracking temperature while maintaining superatmospheric pressure thereon, in then permitting the release of volatile constituents therefrom in the form of vapors, in

separately removing the non-vaporized constituents of the charging stock and subjecting same to cracking conditions of temperature and superatmospheric pressure to effect substantial vaporization, separating the vapors and subjecting same to reflux condensation, in withdrawing the reflux condensate formed thereby, combining same with the preheated charging stock prior to the release of the volatile constituents therefrom, and materially reducing the pressure before the said reflux condensate and preheated charging stock have been merged, whereby lighter fractions entrained in said reflux condensate will be released in the form of vapors.

3. A method for cracking hydrocarbon oil comprising subjecting the oil to cracking conditions in a still, passing vapors evolved from the oil to a dephlegmator, flowing charging oil for the process in heat interchange relation but out of contact with the vapors in the dephlegmator, V

phlegmation or the charging oil during its passage through the dephlegmator in heat interchange relation with the vapors, taking off dephlegmated vapors from said dephlegmator, injecting the same into the commingled reflux condensate and charging oil in the evaporating zone, and passing unvaporized oil from said evaporating zone to the still.

JACOB BENJAMIN HELD.

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