US1394481A - Process of cracking and distilling oil - Google Patents

Description

1. T. FENTON. PROCESS 0F CRACKING AND DISULLING 0H..

`APPLICATION FILED HAY 1. |920.

2 SHEETSf-SHEE I.

patented oct. 18,1921.l

N mw J. T. FENTON.

PROCESS 0F CHAGKING AND DISTILU'NG OIL.

APPLICATION mio MV1. 1920.

1,394,481, Patented oct. 18, 1921.

I UNITED STATES W rari-:NT oF-FICE.-

JAMES T. BENTON, 0F SAII'AI?r LAKE CITY, UTAH.

PROCESS 0F CRACKING AND DISTILLING OIL.

Specication ot Letters Patent.

p Patented Oct. 18, 1921.

Application filed lay 1, 1920. Serial No. 378,216.

tion is applicable to the treatment of vari-- ous kinds of oils, either mineral oils containing paraifins alone or those containing paraffins and other bodies, such as asphalts, or oils containing aromatic substances, such as crude creosote, crude naphthalenes, etc., for the production of benzene (CeI-I, which latter substance is to be clearly distinguished from benzin, a product of petroleum). p

In the system of cracking or breaking up the molecular structures of various organic substances (contrary to most of the accepted principles of the processes heretofore proposed), the 'cracking or breaking up is not produced by keeping the material to be cracked, and the cracking or distilling medium apart, but in this system the cracking and distilling medium, superheated steain, is mixed directly with the material to be cracked and distilled and kept in a state of constant motion and agitation, so that in passing through the various portions of the apparatus, the heat of the steam is brought into more intimate contact -With the oil un# der treatment, and the effectiveness of the heat supplied is very greatly enhanced. l In the system, the production of coke is entirel eradicated, there being no coke and no vree carbon produced at any stage of thev process, since the oil and the steam are maintained in a constant state of agitation, whereby no destructive distillation can be produced.

A feature of great importance in connection with the process is that through the interaction of the steam and the oil, such contents of crude oil as the natural aromatic gums, etc., will be effectively separated from the lighter fractions (for example gasolene) slnce the former occupies a point of condensation far above that of the gasolene. From this it follows that the gasolenes produced in accordance with my invention will' require practically no refining, and hence the expense of refining and the refining loss are both avoided.

Another important feature of the invention is that the oils are cracked and distilled in their entirety and instantaneously, ex cept the heavy portions of the oil, such as paraiiin wax, cylinder stock, etc., which it is desired not to crack.

Apparatus in accordance with the present invention is illustrated diagrammatically in the annexed drawings forming a art of this specification, but it is to be un erst/ood that these drawings show one modification only, and that the invention is not limited to the particular embodiment of the vinvention illustrated in the drawings.

In said drawings, Figure 1 shows a dia# grammatic side elevation (parts in section) of an entire apparatus suitable for use in the present process. Fig. 2 shows, ona somewhat larger scale, the preferred construction of the crackingl chambers, ,'and

their connections.

Fig. 3 is a cross section of the chamber, showing the spiral vanes, and F'g. 4 is a detail view.

Referring more particularly to the detailed construction shown in the drawings, oil`is introduced through the oil feed pipe 10 into a preheater 11, in which lthe o1l is warmed up, but not vaporized. The warm oil passes throughpipe 12 into a mixer 13, which it will be noted is in the form of an injector, high temperature superheated steam being introduced through piped/1. The mixture of oil and superheated steam pass through the pipe 15 into the first cracking chamber 16 in which the oil is instantaneously vaporized, or vaporized all except the heaviest constituents, which as above noted, it is desired not to crack. From the first cracking chamber the vaporized oil, together with unvaporized fractions, pass through pipe 17 into the mixer 18, where it is again mixed with high pressure superheated steam. from the pipe 19. The mixture flows through pipe 20 lnto a second cracking chamber 21, in which the cracking operation is completed. The resulting gases and vapors flow through pipe 22 into the settling and separating tank 23 where they are expanded. A baille 24 is preferably located a' short distance in front of the outlet of the pipe 22, in order to thorresponding acid products.

oughl mix and commingle the vapors and in or er to assist in the separation of the heavy constituents of the oil, which are not to be cracked.

The heavy-.constituents are drawn of in liquid form-- through the valved voutlet trap 25 and the remaining gases and vapors pass off throng pipe 26, into a series of condensers 2 28, 29 and 30,` in which' the various grades of oil condense, the least volatile portion condensing in the condenser 27, another portion, saylight spindle oils collecting inthe condenser 28, kerosene condensing in lthe condenser 29 and gasolene `condensing in the condenser 30. The resulting gases containing light vapors then pass to a rhigolene condenser 31, in which the gases and vapprs are preferably cooled to such as extent as to\condense the rhigolene. The remaining gases and vapors containin substantial amounts of ethylene and other ydrocarbons of the olefin series `ass off through thepipe 32 into the sul uric acid absorbers 33, in which the ethylene is converted into etlwl sulfuric acid, and other gaseous olefins are converted into the cor- The vapors issuing at 34 may then be compressed and cooled. for the purpose of collecting cvmogene.

In the above example, I have described particularly the treatment of a petroleum oil, but I wish it to be understood that 1u place of a crude petroleum, a petroleum distillate can be employed for example kerosene, solar oil, gas oil or the like, and if desired, also crude creosotes or crude naph- Y thalenes may likewise be treated for the production of benzols CI-I, and other aromatics.

By referring to Figs. 2 and 3, it will be noted that the cracking receptacle 16 is provided with a heavy heat insulating layer 36,

and that inside of this receptacle there is provided if desired a vane or ridge 38 of any desired height, for the purpose of giving a whirling motion to the gases and vapors therein. While itis not absolutely necessary that such vane or projection be provided, it is advisable to provide the same in order to more thoroughly mix and commingle the oil vapor and superheated steam.

i The superheated steam supplied by pipes 14 and 19 is under high pressure and is highly superheated, in order to produce and main- 1 tain the necessary heat and pressure in the cracking retorts.

The entire cracking operation is carried out under a superatmospheric pressure and at a high temperature. The temperature in the first cracking chamber may be from 500 to 700 F., and the temperature in the second may be from 700 to 1000 -F., and the pressure in the first chamber may be ,from 20 to 50 pounds per chamber may and in the second cracking be from v50 to 80 pounds per Square inch. Each particular grade of o l is best treated at a particular temperature, which is found in practice to be most advantageous for that particular grade of oil to produce just the desired extent of crack ing and no more.

The pressure and temperature are mam'- tained at the point necessary with each particular oil to regulate and control the de gree of cracking. Accordin ly, it is not possible to give any articu ar statements of exact pressure an temperatures to be em loyed.

t is to be noted that al1 of the heat and all of the pressure are supplied by means of the superheated steam introduced through the pipes 14 and 19, and itis not necessary to pass the oil vapor or theoil while undergoin decomposition through coils or chambers located 1n furnaces which operation has been heretofore usually considered essential in oil cracking, and this has been open to the objections of producing considerab e quantities of coke or hard carsquare inch,

bon, by a far-reaching cracking operation..

Such production of coke is entirely avoided in the present case, by avoidin the unnecessary high heats and the val able portions of the oil under treatment which would be. cracked in this manner are thereby saved.

The oil preheater 11 may in some cases be dispensed with. However, I find it advisable to preheat the oil to a temperature of, say, 100 to 150 C., or in any event, to not over 175 to 200 C., before the same is first treated with the superheated steam. operation is for the purpose of imparting some heat to the oil without any danger of cracking before the same enters the process. The oil entering pipe 12 may jbe at about atmospheric pressure or a slight pressure may exist due to the head of oil coming from the oil tank which may be located at a higher level. This amount of pressure, however, is negligible and may be disregarded for the purpose of the present invention.

In connection withthe advantages of the system of cracking oil, as hereinabove described, I call attention to the feature that This all of the oil cracking is produced simulnumerous roposed in which the cracking is produced ractionally or in a' number of successive stages. Also it is particularly7 upon a crude oil or an oil left a ter distilling olf some ofthe lighter fractions, it is advisable not to crack the cylinder stock, which is of much greater value than gasolene. In ordinary cracking of petroleum oils, in accordance with the presentdnv'ention the idea isA to produce as much as postaneously as distinguished from )rior processes which have been noted that-in o erating `sible2 of the gasolene or petroleum ether lother portions of the apparatus.

fractions with' the production of a minimum of the other materials present.

t A further adyantage to be noted is that' the apparatus does not have to be operated continuously to prevent freezing vup, since there are no accumulations of heavy materials to freeze up in the plant if allowed to' the rocess it is necgoA cold. F or stoppin Hg the eed of oil, allow essary onl to shut o then be cut oir and the plant allowed to cool.

Similarly, in starting operations, it is nec essary'only to blow steam throughtthe ap paratus for a short time in order to preheat ity and then after the workin temperature has been reached, turn on t e oil feed and the c cking operation begins at once, thereby it being readily posslble, starting from a cold ap aratus, to have the'cracking process undgr way at full capacity in from 20 to 30 minutes.

A feature of importance is the instant and absolute /control ofthe ratios of steam and oil, depending upon the particular` kind of oil treated. l v

The process involves the law which may be expressed as follows the boiling point of mixed liquids which do not dissolve in each other is determined by their combined-vapor pressures. When the combined vapor pres?l sures is equal to the external pressure both li uids will disti'l."7

t is advisable, as shown in Fig. 2 of the drawing, to make the rear ends of the chambers (orthe ends opposite to the intake of the va r to the chambers) renewable, since the friction ofthe oil vapor and steam pounding against `these bottoms mavwear out the same in a relatively short time, or much before the normal wearing out of the It is, in many cases, also advisable to place the bafiie plate 40` in each of these chambers as` illustrated in Fig. 2,l so that the vapors and gases will impinge upon this baile plate 40 which may be readily renewable., If desired, the`bale plate 40 may be given any desired shape in order to produce a rotary or whirling action of the gases and vapors in the chambers, so as to produce more complete mixing. For this purpose, a plate with a spirally grooved cone center may be useful, as shown at 40 in Figs. 3 and 4.

.I have above referred to, the absenceiof extraneous heating by furnaces and the like, such las common in the prior patents, which have been issued in vthis art.

The ethylene sulfuric acid produced in the sulfuric acid absorption a paratus as well as the other members of tlils series can be used for the production of alcohols, Aby appropriate treatment withwater, so that al-` low through the ap aratus for' a few 'minutes andthe whole p ant will be'r clear and clean and the iowof steam canr lcohol may constitute ahy-product of ther process.

I desire to call particular attention to the i fact that in my process, it is advisable to vso adjust the temperature, pressure, proparaiiin andlgasolene.'4 In the drawing, I have shown four conthe products whichat the present time are v Yofflow value, relatively to the cylinder oil,

dansers, 27, 28, 29 and 30.` It is, of course, to u be understood that the number of condensersl may be greatly increased, if desired, thus for example, instead of using four only, I might employ ten or morel of such condensers, depending upon the number of se arate products which are to be recovered rom a given treatment. The temperature of the several condensers will be controlled by suitable cooling baths, so that the roducts condensed therein will, usually wit out further refining, be suitable for placing on the market.

n a modified form of operation, the temperatures employed in the various steps of the process may be so adjusted that the operations which go on will be principally dis- Itilling, without any substantial amount of cracking. For' this, low temperatures will usually be employed in the vessels 16 and 21.

No claim is made herein to the apparatus hereinbefore described and shown in the accompanying drawings as claims thereto are made in m application for Patent No.

'438,977,61e Jan. 21, 1921.

I claim: 1. The hereinbefore described process of treating oils which consists in cracking or disrupting thd molecular structure of the oils by heat supplied solely .by the direct contact of super cated steam under ressure with said oils while in a subdivi ed and agitated condition and while continuously flowing from a source of supply toward a condenser; so controlling the heat and pressure of the superheated steam as to crack a portion of the constituents o f the oil, passing the crackedand uncracked constituents to a se arator, there expanding and separating sa1d constituents, drawing oil' the heavier fractions, and then' progressively condensing the lighter fractions of the roduct.

2. The rocess hereinbefore with superheated steam 'under pressure, subescribed of Itreating oils which consists in mixing the oil dividing and agitating the oil while in direct contact with the steam and whileunder pressure in a cracking chamber, passing all of the products of the first chamber to a similar second chamber, there subjecting the contents of the second chamber to the direct action of a second supply of steam at :i higher temperature and vunder greater pressure, arising the oil and steam to flow continuously from a source of supply toward a condenser. so controlling the heat and pres sure of the steam as to crack a portion of the constituents of the oil, passing all of the constituents to a; separator, there expanding and separating the uncracked constituents from the others, and then condensing the lighter fractions of the product; the heat and pressure for the cracking operation bcing supplied solely by the superheatcd steam under pressu1c,substantially as described.

In testimony whereof, I have hereunto subscribed my name.

JAMS T. VFEN'ro-N.

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