US1281884A - Process and apparatus for converting petroleum-oils. - Google Patents

Description

. M. J. TRUMBLE. PROCESS AND APPARATUS FOR CONVERTINQ PETROLEUM OILS.

APPLICATION FILED JULY 19. 1915.

4', Patented Oct. 15, 1918 5 SHEETS-SHEET 1- M. J. IRUMBLE.

PROCESS AND APPARATUS FOR CONVERTING PETROLEUM OILS.-

APPLICATION FILED JULY 19.1915;

1,281,884. Patented 0ct.15, 1918.

s SHEETS-SHEET 2.

IVIJI. TRUMB LE.

PROCESS AND APPARATUS FOR CONVERTING PETROLEUM OILS.

APPLICATION FILED .IULY I9 I 9I5.

Patented Oct. 15, 1918.

mama

' 5 SHEETS-SHEET 3.

Q5 Q6 Q8 M J. T RUMBLE. PROCESS AND APPARATUSFOR CONVERTING PETROLEUM OILS.

APPLICATION FILED JULY 19.1 915. I

Patented Oct. 15, 1918.

5 SHEETS-SHEET 4.

M. J. TRUMBLE.

PROCESS AND APPARATUS FOR CONVERTING PETROLEUM OILS.

APPLICATION man JULY 19.]9l5.

mama

Patented 0ct.15, 1918.

5 SHEETS-SHEET 5.

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MILON J. '.I'.'BUMBLE, OF LOS ANGELES, CALIFORNIA, ASSIGNOR BY MESNE ASSIGN- MEETS, T0 SHELL COMPANY OF CALIFORNIA, 01 SA}? FRANCISCQ-CALIFORNIA, A

CORPORATION 0E CALIFOR N'TA.

rnocnss m APPARATUS FOR convna'rme rnrnonnumorns.

Patented 0st. 15, 1918.

Original application filed July .19, 1915, Serial No. 4Q,794. Divided and this application filed July 19, 1 915. Serial No. 40,795.

To all whom it may concern:

Be it known that I, MILoN J. TRUMBLE, a citizen of the United States, residing at Los Angeles, in,the county of Los Angeles, State of California, have invented a new and useful Process and Apparatus for Converting Petroleum-Oils, of which the following is a specification. I

This application is a d1v1s1on of an accompanying application for an apparatus for convertmg petroleum 011s, serial No. 40,794, filed July 19, 1915.

The invention relates to the art of refining petroleum oils, and its principal ob- .ject is to provide a process apparatus by which petroleum 011s of h gh specific gravitymay be converted into 0115 of much lower specific gravity. There is at the resent time a large production of 011s of gh specific gravity, hereinafter called heavy o ls, and such oils are of much less commercial value than oils of low specific gravity hereinafter called light oils. The process and apparatus described herein has been used on a large scale to convert heavy 0115 into llght oils.

The conversion of heavy oils into light oils has been previously accomplished in a crude way by various methods which are known in the art as crackir ig processes.- Previous inventors have devised many forms of apparatus for cracking oils. This they have sought, to accomplish by heat, with or without pressure, in some cases using var1ous catalytic agents such as nickel, alumina, etc. The process described herein has the following advantages. 0

irst, the .process described hereln IS a continuous one, in which a definite volume of heavy oil is maintained in rapid motion at a cracking temperature through apparatus forming a-closed ring, light oil vapors being removed as fast as formed, and fresh oil being continuallysupplicd to take the )lace' of the vapors withdrawn so that the v0 ume of oil in the closed ring is maintained practically constant. In actual operation in large refineries the apparatus described has demonstrated that it can operate over a long period, continuously converting large quan tities of heavy oils into light oils.

Second, it providesan apparatus in which the actual volume of heated oil is small, the

large capacit of the apparatus being due to the high e ciency of the various parts.-

Where the ordinary form of cracking stills is used a large capacity can be economically obtained only by using large units, which, when running contain a large quantity of oil heated to such a temperature that it will spontaneously ignite when released into the air. A leak or break in such a still will result in the ejection of large volumes of highly heated oil which burns with great violence. This condition becomes more seriouswhere the still is used under pressure. With the small volume of oil contained in the apparatus disclosed herein such serious confiagrations cannot occur. The apparatus therefore combines large capacity with great safety.

Third, the oil contained in the closed ring described above is forced through the heating means at a high velocity. The heating means comprises a series of pipes suitably connected to form a single continuous heating coil. The oil enters the coil at a moderate velocity and as it passes through the coil large quantities of vapor are gradually produced therein. timately mixed with the body of the oil due to its rapid motion forming a foam which gradually increases in volume andconse- This vapor remains inquently travels with an increasing velocity through the heating coil.

tion of carbon, or other solid or viscous materials on the interior of the heating coil so that the apparatus cannot become clogged or the efficiency of the heating surface destroyed by such deposition.

(d) This high velocity prevents unequal I heating of the heating coil as all parts of the coil are uniformly cooled by the il flowing thcrethrough. The uniform a moderate heating of the coil gives the apparatus a long life and results in great safety of operation.

Fourth, the apparatus disclosed herein is especially adapted to work under pressure.

It is a well known fact that the character of the roducs obtained from petroleum oilsby crac ing is not only dependent on the temperature but also to a very great degree on the pressure under which the cracking takes place. The heating coil being composed of pipes is well adapted to stand hlgh pressures even when heated, and these pressures are readily controlled by an adjustable valve through which the heating coil discharges.

Fifth, the apparatus is especially adapted to maintain constant the conditions under which the oil circulates through the closed ring, and to maintain constant the composition of the oil and the percentage of solid matter carried therein. Solid substances may be contained in the oil introduced into the apparatus, and solid hydrocarbons or even free carbon ma be formed in the ap; paratus. Such soli substances cannot vaporized and it is important that the circulating oil be relieved of them at the same. rate at which they are formed if the com.

position of the oil is to bemaintained constant. This condition of equilibrium is maintained in the closed ring by a constant withdrawal of light va ors, a constant with drawal'of heavy oil an included solids, and a constant replacement of the volume so withdrawn by fresh oil. The heavy oil can be conveniently withdrawn from the bottom of the settling tank forming a portion of the closed ring.

x In practice a very small flow of heavy oil through the relief pipe is sufiicient to prevent undue accumulations of objectionable solids in the body of the circulating oil. For example with California oils on which the apparatus has been commercially operated the amount of oil withdrawn through the relief pipe is less than five per cent. of the oil introduced through the makeup pump.

Thle apparatus described herein differs eat om the ordinary forms of crackin stills.

In such stills a constant character 0 product cannot be obtained as the condition of the oil in the still and consequently the character of the product obtained changes gradually as the process proceeds.

In the apparatus described herein the oil circulating in the closed ring is maintained under constant conditions of temperature,

pressure, and com 'tion, so that the character of the P not obtained is constant. However, the temperature, pressure and com in method of operation and results for retreatment. This is important as it may be undesirable, or even impossible, in the practical operation of the apparatus to regulate the conditions in the closed rin to such a degree that only the desired pro not 'is produced. It is especially easy to operate various forms of fractionating apparatus with the apparatus disclosed hereln as the character of the va ors given off, and the rate of flow thereo is constant. The firactionatmg apparatus can therefore be operated under certain constant conditions with a consequent large capacity and high efliciency.

In the drawings which'are for illustrative purposes only:

Figure 1 is a plan view showing a certain arrangement of apparatus which is adapted to carryon the recess.

Fig. 2 is an evation of said apparatus.

Fig. 3 is a. section on a' lane represented by the line 01 -02 in'Fig. 1 ooking 1n the direction of the arrows.

Fig. 4 is a section on a plane represented by the line 29-h in Fig. 1 looking-in the direction of the arrows.

Fig. 5 is a section on the plane represented by the line w en in Fig. 3 looking in the direction of the arrows.

Fig. 6 is a section on the plane represented by the line w-a:. in Fig. 4 looking in the direction of the arrows.

Fig. 7 is a section on the plane represented by the line a:-:c' in Fig. 3 looking in the direction of the arrows.

Fig. 8 shows a schematic diagram illustrating the process in a simple form.

Fig. 9 shows a similar diagram illustrating a modification of the roeess.

In the following description the term and a condenser 5. A circulatin pump 6' delivers oil from the settling tank 3 to the coil 1, crude oil is delivered to the coil 1 from a tank 7 by a make-up ump 8, and

heavy oil with its included so ds is drawn from the settling tank 3 by a relief pump 9.

The heating coil 1 is'placed in a furnace 10 and consists of a series of pipes 11 joined into a continuous coil bv pipe fittings 12 and 13. An inlet T 14 and an outletelbow 15 atest i are secured on either end of the coil 1.' Oil burners 16 of any well known form extend into the furnace 10, being fed with fuel from a fuel supply pipe 17.

The vapor releaser 2 may be of any suitable form. The form shown consists of a' shell 18 having secured thereto a top19 and a conical bottom 20. A hot mixture pipe 21 discharges through the top 19 being connected to a pressure control valve 22 which is connected to the elbow 15. Deflecting cones 23 are secured on pipe members 24 which are connected by PS 25 to vapor outlet pipes 26. The vapor outlet pipes 26 pass through the shell18, a tight jointthere; withbeing insured by flanges 27. The cones 23 are of such a diameter that a small annular space is left between their outer edge and the inner wall of the shell 18. The pipe members 24: have perforations 28 cut there- 7 in. The vapor releaser may be heat insulated by proper covering material, or preferably it may be supported in a stack 29, as shown, being partially heat insulated by the use of a fire brick wall which surrounds it. An opening 30 connects the lower part of the stack with the interior of the furnace 10. An annular space 31 allows hot gases to as cend between the vapor releaser 2 and the wall of the stack.

The settling tank 3 illustrated consists of a shell 32 having a tight top 33 and a conical bottom 34. A residuum outlet pipe 35 connects the bottom 20 of the releaser 2 with the top 33 of the settling tank 3. A series of perforated deflecting and mixin cones 36 may be located in the settling tank 3 if desired.- Pet cocks 37 allow the height of liquid in the-settling tank to be readily determined. The settling tank may have heat insulation 38. applied thereto. If desired the settling tank 3 may be dispensed with, the bottom of the vapor releaser 2 'being utilized as a settling tank. For clearness in description the settling tank is shown as a separate piece of apparatus.

An outlet ppxenmg 39 is provided in the side of the ta 3, a pipe 40 connecting this outlet with the circulating pump 6. A pipe 41 connects the pump 6 with the inlet T 1-1 to which is also connected the crude oil inlet pipe 42 which is fed from the tank 7 through a pipe '43 and the make-up pump 8. A relief pipe 44 connects the relief ump 9 to the conical bottom 34 of the se tling tank 3.

A vapor column 45 connects the vapor outlet pipes 26 to the lower portion of one of the dephlegmators 4. These may be of any of the well known forms, those illustrated consisting of a shell 46 having a tight cover 47 and a conical bottom 48. A series of conden ation plates 49 extend across the interior of the shell 46 having openings 50 formed therein. the openings 50 having a from the tank 7.

raised lip 51 so that condensates can collect on top of each )late 49, the openings 50 in the different plates-bein staggered with relation to each other. The .top portion of the first dephlegmator is connected to the bottom of the second dephlegmator by a pipe 52.

Any form of condenser 5 may be used.

That illustrated consists of a shell 53 havfitting 61 delivers light distillate to a pipe 62 from the bottom of that space. WVater is supplied to the spaces 56 and 58 and to the interior of the tubes 59 by a water inlet pipe 63, this water being discharged through a water outlet pipe 64. The top portion of the last dephlegmator 4 is connected to the vapor inlet fitting 60 through a pipe 65. A distillate discharge pipe 66 connects to the lower end of the conical bottom 48 of the first dephlegmator 4, and a-similar pipe 67 is similarly connected to the second dephlegmator 4. The pipe 67 may be connected wit 1 'a distillate return pipe 68 through a valve 69', and pipe 67 may also be connected to the pipe 68 through a valve 70- The pipe 66 may also be connected to a heavy distillate discharge pipe 71 through a valve 72,

and the pipe 6 may be connected to a heavy distillate discharge pipe 73 through a valve 74. The fuel supply pipe 17 connects into a T 75 to which are connected valves 76 and 77. -A fuel pipe 78 connects into the valve 7 6 and a pipe 79 connects the valve 77 with a T 80 into whichis connected a valve 81, this valve being connected to a heavy oil discharge pipe 82. The T 80 is connected to the pump 9 through a pipe 83.

The method of operation of the apparatus is as follows:

Crude oil is pumped to the inlet T14 through the pipe 42 by the make-up pump 8, this oil being drawn through the pipe 43 Oil from the inlet T 11 flows through the pipes 11 and the fittings 12 and '13 to the outlet elbow 15 and through the valve 22 to the pipe21. It is discharged from the pipe 21 into the vapor releaser 2 flowing downwardly therethrough and through the pipe 35 into the settling 'tank 3. As soon as sufficient oil collects in the settling tank 3, which can be. ascertained by the pet cocks 37, the circulating pump 6 ,settling tank 3, the pipe 40, and the pump 6. The burners 16 are then lighted, oil being supplied from the pipe 17. It is necessary to fill the various parts of the closed ring with oil and to put this oil 'into rapid motion before the burners arev lighted as v there would otherwise be danger of too rapidly vaporizing. the oil in the pipes 12. The pipe 17 through the pipe 78, the valve 76 being open and the valve 77 being closed, or the valves '7 6 and 81 may be closed and the valve 77 opened, in which case oil is fed into the pipe 17 through the valve 7 7 from the pipe 83, this oil'bein taken off from the settling tank 3throug the pipe 44 and the pump 9.

When the oil-taken. off from the settling tank through the pipe 44 is not used for fuel purposes, the valve 77 may be closed and the valve 81 opened, in which case the oil is delivered to suitable tankage not shown through the pipe 82. The flame and .hot gases of the burners 16 play against the pipes 11 of .the heating coil 1 and escape through the opening 30 into the stack 29 where they ascend through the annular space 31 between the shell 18 and the inner wall of the stack. The oil in the closed ring is rapidly heated, and as it enters the vapor releaser 2 is spread in a thin film overthe inner walls of the shell 18'by the cones 23, vapors escaping from the film passing through the openings 28 into the pipes 24 and through the vapor outlet pipes into the vapor column 45. The further course of the vapors will beset forth hereinafter.

of these substances as well as any similar substances formed in the oil in its circulation through the closed ring must there-- fore remain in the oil' afterit has passed through the vapor releaser 2, and unless some means were provided to dispose of them, must eventually choke the closed ring or at least render the oil in it of such a character that little evaporation or cracking could take place therefrom.

To relieve this condition, a small quantity of 011 1s constantly withdrawn from the extreme bottom of the settling tank 3, this material .being conveniently disposed of by feeding it by means of the pump 9 and the pipe 17 to the burners 16 where it is readily burned. The oil being somewhat reduced in velocity in passing through the settling tank, any material that will settle anywhere may be supplied with fuel.

process from a given oil.

in the closed ring will settle to the bottom of the tank. It is not, however, necessary to provide such a settlingtank, as the heavy oil may be removed from the bottom of the vapor releaser orindeedanywhere between the vapor releaser and the inlet to the heating coil. j s

The oil enters the heating coil 1 at a moderate velocity and is practically free from vapor, As it circulates through the heating coil a; portion thereof is broken u' to form a lighter hydrocarbon, the smal globules of light va r being swept on by the moving mass 0 'oil which assumesa foamy nature. This foam-greatly increases the olume of the flowin stream which there ore accelerates rapi y. The movement ofthe oil and vapor through the heatirlg coils is sufiiciently rapid 'to provide high e ciency of heat transfer between the informly heat the oil and vapors, so that none of it is subjected to excessive temperatures, to prevent any deposits of solid or viscous material on the interior of the pipes 11, and to prevent local overheating anywhere in the coil 1, so that the coil' has a long life and is very safe to operate. The foam remains in the heating coil 1 only a very short time, being immediately passed into the 'terior of the pipes 11 and the oil, to univapor releaser 2 where the vapors are withdrawn from the oil. This is important as there is some danger of the vaporsbeing furlther cracked if retained in the heating e01 When operating with some sorts of crude oil, it is necessary to put some pressure on the oil in the heatin coil 1 to produce a desired product. This can be readily done by partially closing the valve 22.

In practical operation, the heat of the fire, the rate of injection of crude oil, the speed of the circulating pum the rate of withdrawal through the relie pipe 44, and the pressure are all regulated so that the oil passing through the closed ring is subjected to a definite and constantly recurring ,cycle of conditions. It is of course obvious and there are therefore practical limitations to the product that can be obtained by this The product can, however, be very materially modified by a suitable modification of the conditions in the closed ring, and one great advantage of the present process is the ease with which conditions in the ring can be modified to produce the best commercial. results.

The vapors in the vapor column 45 may be the desired product, in which case the dephlegmators 4 can be dis nsed with, the vapors being passed direct y into the condenser 5, condensed therein and passed 05 through the pipe 62. 'It may be desired to earner separate the product into distillatcs of several gravities, in which case the dephlegmators are very convenient.

The vapor passes from the vapor column to the bottom of the first dephlegmator and through a tortuous course t rough the openings to the top. The vapors then pass through the pipe 52 to the second dephlegmator and through the openings 50 to the top thereof. The vapors'in passing through the dephlegmators are gradually cooled, a heavy distillate collecting and running over the lips- 51 into the bottom of the first depblegmator. A medium distillate condenses and collects in the second dephlegmator. The vapors not condensed in the dephlegmators are condensed in the condenser 5 to form a light distillate which is delivered through the pipe 62. The heavy .distillate may be a desirable commercial product in which case the valve 69 is closed and the valve 72 is opened, the heavy distillate being delivered through the pipe 71 after cooling to suitable tankage. If the heavy distillate is not a desirable commercial product, the valve 72 may be closed and the valve 69 opened, the heavy distillate being delivered to the pipe 68. If the medium distillate delivered by the pipe 67 is a desirable coinmercial product the: valve is closed and the valve 74 is opened, the medium distillate being delivered after cooling to suit able tankage through'the pipe 71. If this medium distillate is not a desirable commercial product by opening the valve 70 and closing the valve 74 medium distillate can be delivered to the pipe 68. Any distillate delivered to the pipe 68 is returned to the settling tank 3, being delivered onto the mixing plates 36 where it mixes with oil delivered from the vapor releaser 2 through the pipe 35, thereby being reintroduced into the closed ring for retreatment;

It will be seen that the invention consists of the following original'conceptions:

First, the forcing of petroleum oils through a heating coil, heated to a suificient degree to crack the oil, at such a rate and at such a pressure that the oil can be changed into a foam without danger of unduly heating portions thereof or burning the coil, it having been found by the inventor that heavy petroleum oils are changed to light ones by such a process.

Second, the immediate release of the foam so produced, the removal of vapors therefrom and the immediate recirculation and reheating of the oil to form more foam, the oil being kept in continuous motion over a closed ring or path.

Third, the condensation'of a portion of the vapors so produced, and the return to the closed ring of the heavy distillate so puced.

Fourth,euse oithese tank? in on the plates-49 leaser; '...z y

a closed ring and the continuous removal of-heavy oil and foreign matter from the bottom of this'tank, so that accumulations of solid. matter in the ring is prevented and the composition of the oil in the closed ring is maintained constant. I

Fifth, the use of the make-up pump 8 for thepurp'ose of maintaining constant the volume of the closed ring as vapors and heavy oil with included sediments are taken off therefrom.

Sixth,4the use as fuel in the burners 16 of the hot heavy oil from the bottom of the tank 3.

Iclaim as my invention:

1. The process of converting a heavy petroleum oil into a light one which consists in circulating the heavy oil through a closed ring, continuously heatin a portionof the ring, continuously taking ofi light vapors from the ring, continuously relieving the ring of a small amount of heavy oil and continuously supplying fresh oil in suflicient quantities to maintain constant the volume of oil in the'closed ring.

2. The processof converting a heavy petroleum 011 into a light .one which consists in circulating the heavy-oil'through a closed ring, continuously heating a portion of the ring, maintaining a pressure on the portion of the ring so heated, continuously taking 03 light vapors from the ring, continuously relieving the ring of a small amount of heavy oil and continuously supplying fresh oil in suilicient quantities to maintain constant the volume of oil in the closed ring.

3. The process of converting a heavy etroleum oil into a light petroleum oil WhlCh comprises, first, forcing the heavy -oil through a heating coil, said .coil being heated to a sufiicient degree to crack the 011, said heavy oil being forced through said coil at such a rate and at such a pressure that the oil is changed into foam without danger of unduly burning portions thereof, second, removing light vapors from the stream of oil, third, recirculating the residuum left after said vapors are removed through said heating coil to form more foam, said oil thus belng kept in continuous movement over a closed path orsring, fourth, condensin a. portion of the vapors so removed, the tillates so condensed being returned to the closed ring for retreatment, fifth, constantl removing a small portion of the heavy 011 and included solids from the ring, and

simultaneously with the above steps supplying crude oil to said rin to re lace any diminution in volume of t e oil erein, so that the volume of oil in said ring is maintained constant.

4. An apparatus for converting heavy pe-- troleum mixtures into light petroleum oils,

comprising a heatin means; a vapor refor con a F 3 the heated mixturefrom the primary heating means to .the vapor releaser; means for withdrawing light vapors from the vapor releaser; means for continuously withdrawing a. portion of the mixture; means for forcing the residuum from the vapor releaser through the primary heating means;and means for injecting sutiicient fresh heavy -oil into, said residmun to maintain the volume of oil 'in' tl e apparatus approximately constant.

5. An ap -raratus for treating liquids coin;

prising a urnace; a burner for said'furnace; a heating coil in said furnace; a vapor releaser; pipes connecting said heating coil with said releaser; a ser es of dephlegmators; pipes conducting the vapors from said vapor releaser successively through said dephlegmators; a condenser; a circulating pump; pipes delivering the residuum from said vapor releaser to the suction side of said pump; a make up, pump; a crudeoil supply pipe delivering crude oil to the sucprising a settling tank through which the residuum from said vapor releaser passes on its way to saidvcireulating pump, said relief pipe being connected into said settling tank.

7. An a )paratus for treating 1i uids comprising a urnace; a burner for sai furnace;

a heating coil .in said furnace; a 'vapor relea'ser; pipes connecting said heating coil with said releaser; a circulating pump; pipes delivering-the residuum from'said vapor rel'easerto the suction side of said pump; a make up pump; a crude oil supply pipe delivering. crude oil to the suction side of said make up pump; pipescoxinecting the pressure side of said make up .pump and said circulating pump with the inlet to said heating coil; and a relief pipe through which a portion of the residuum'from said" vapor releaser can be withdrawn from the system. p I

8. An apparatus as in claim 7 also comprising a settling tank through which the residuum from said vapor releaser passes on its way to said circulating pump; said reliefkpipe being connected into said settling tan V In=testimony whereof, I have hereunto set mv hand at Los Angeles', California, this 10th day of July, 1915.

MILON J. TRUMBLE.

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