US1947319A - Preheating chamber - Google Patents

Description

Feb. 13, 1934. E. w. THIELE I PREHEATING CHAMBER Filed Jan. 14, 1929 2 Sheets-Sheet 1 fivenzaf' ZZKZZL'eZe,

Patented Feb. 13, 1934- l'ATENT oFFicE PREHEATING CHAMBER Ernest 'W. Thiele, Chicago,

Standard Oil Company, Indiana, a corporation of Indiana Application January 14,

9 Claims.

The present invention relates to the preheating of chambers or retorts, and particularly relates to methods and apparatus in which a plurality of chambers or retorts are employed in succession (3 or rotation for the reception of heated liquids,

such as hydrocarbon oils, and the like.

While the invention is capable of wide appli-- cation, it is particularly applicable in connection with apparatus comprising a plurality of chamt bers adapted to be used successively, being supplied with highly heated hydrocarbon oil which is subjected to pyrolytic decomposition or destructive distillation in said chambers.

By way of example, the invention is described in its application to the method of distilling hydrocarbon oil residues described in the co-pending application of Robert E. Wilson, Serial No. 329,419, filed December 31, 1928.

A suitable apparatus for such distillation is il lustrated in the accompanying drawings, in which Figure 1 is a diagrammatic view of an apparatus suitable for effecting the complete distillation of such residues; and Fig. 2 is an elevational view on a larger scale of a suitable form of distillation chamber.

Referring to the accompanying drawings, a fire and steam still 10, which is the last of a series of continuous stills, is shown as the source of hot petroleum residue. The source may, however, be the flash drum of a pipe still, or other convenient source of hot heavy residue from crude oil, which has preferably been subjected to but little cracking or decomposition. The residue passes by pipe 11 to a pump 12. In case of difficulty in pumping the hot residue, a cooler 13 is provided for the purpose of slightly reducing its temperature to a point at which satisfactory positive pumping may be efiected. The pipe 11 is co provided with a valve 14 and a valved pipe 15 leads into the pipe 11 between the valve 14: and the pump. 12. I

The outlet 16 of the pump 12 leads into a suitable pipe still, shown diagrammatically at 1'7, in which most of the heat is preferably supplied by radiation. The outlet 18 of the coil leads into a plurality of manifolds 18, suitably three in number, each of which is connected by valved pipes 19 with one of the insulated or lightly fired chambers 20. The chambers 20 are of substantial dimensions, and are intended to contain the heated oil while distillation to coke takes place. The chambers 20 are preferably vertical and are provided at their upper ends with valved pipes 21 which open to the atmosphere. A valved va- 111., assignor to Whiting, Ind,

1929. Serial No. 332,541 (01. 196-58) 29 extends to a manifold 30 from which valved connections extend to each of the manifolds 18, so that the vapors, or a part thereof, formed in one chamber may be passed through another empty chamber thereby preheating it for the reception of residue to be distilled to coke.

The chambers 20 are mounted in an elevated position on suitable supporting structures 31 which permit access to their lower ends where the chambers are provided with removable closures 32. The closures 32 are provided with valved pipes 33 for the supply of air or other fluid into the chamber. The pipes 19, associated with each chamber 20, communicate thereinto at various levels-thereof. The lowest pipe 19 is preferably removably coupled to the pipe 33 so that the heated residue can be supplied into the base of the chamber 20.

The closure 32 may be provided with a small manhole 34, if desired.

The fractionating column 23 may suitably be of the bubble plate type. It is provided with suitable means (not shown) for supplying reflux or condensing vapors to serve as reflux. From the base of the column 23 leads a valved conduit 35, which is provided with a pump 36 and valved branches 37 and 38 connecting with the inlet and outlet, respectively, of the pipe still 17, so that a controlled amount of the heaviest condensate, together with any entrained tar may be returned to the chamber 20. A valved outlet 39 leads from the column 23 at a somewhat elevated point, for example from the second or third plate above the point of admission of the vapors, for the purpose of withdrawing clean charging stock.

The operation is as follows: One of the chambers 20 must first be brought to an elevated temperature so that it will not cool the heatedresidue below cracking temperature. The heating of the chamber may be eifected in any suitable manner. For example, it may be heated by passing steam or water through pipes 15 and 16 into the pipe still 1'7 and passing the highly superheated steam thereinto by pipe 18, the associated manifold 18 and one or more of the associated pipes 19. It has been found that even better results can be obtained by supplying an oil, such as gas oil, in a similar manner, the vapors therefrom passing by pipe 22 to the condenser 25 where they are condensed; Condensate formed in the chambers 20 during the-initial stages of heating up may be withdrawn through pipe 33.

Another method of preheating the chamber 20 is by combustion therein. In preheating by this method the valve in pipe 21 is opened and those in pipe 22 and in the connecting pipe 29 are closed. Compressed air is supplied by pipe 33. Any suitable combustible material, for example gas, may be supplied into the chamber and taken to prevent local overheating of the walls, or the formation of an explosive mixture within the chamber. combustion from any suitable furnace, such as a portable chamber, may be introduced through the pipe 33 or other suitable point of entry, such as the manhole 34.

The chamber 20 having been brought to a satisfactory temperature, for example 650 F. or preferably higher, petroleum residue, preferably at a high temperature, is supplied by pump 12 to the pipe still 17, through which it is forced at sufficient speed to prevent excessive cracking residues from Mid-Continent crude the temperature of the entering oil must be above 870 F. to insure the production of a reasonably satisfactory coke without too much volatile matter, while temperatures above 940 F. tend to cause excessive coke formation in the tubes.

The highly heated residuum is admitted into the chamber 20 by means of one or more of the pipes 19, and builds up from the bottom, coking by its contained heat until the chamber is substantially full. It is preferred to supply the heatchamber 20 in which distillation is being con- 'ducted, by means of pipes 29, 30, 18 and 19 into the chamber 20, next to be used to preheat the latter. The vapors pass from the latter chamber 20 by pipe 22 into the fractionating column 23. The fractionating column is supplied with reflux or cooling medium in suitable amount to yield an overhead of gasoline or pressure distillate, which is condensed in the condenser 25. The condensate collects in the receiver 26, from which it is drawn off at suitable intervals. The gas and uncondensed vapors escape by pipe 28 and pass to suitable means (not shown) for recovery of the gasoline therein.

Cleancracking stock is withdrawn by the pipe 39. The reflux from the lowest two or three plates is not sufficiently "clean and is preferably returned by pipe 35 to either the inlet or outlet of the pipe still 17.

. It is preferred to maintain the chambers 20 Also, moderately hot products of at approximately atmospheric pressure. Accordingly, the pressure applied by the pump 12 is sufficient to force the residue through the pipe still 17 at the desired rate.. The destructive distillation may be effected, however, at moderately super-atmospheric pressures, if desired.

The invention will be more readily understood from the following specific example of operation on a small commercial scale:

Mid-Continent crude oil is run to a bottom of about 8 to 10% by volume in continuous stills and is withdrawnat the rate of about 20 barrels an hour from the last still 10. The residuum is cooled to 720 F. in the cooler 13, since difllculties are experienced in pumping it at higher temperatures. The residuum is pumped through the pipe-still 17, which has eighty-seven tubes of two inches diameter, each approximately fourteen feet long. The outlet temperature is 910 F. The residuum thus preheated is introduced into one of the chambers 20 which had been preheated as described above, and is maintained at substantially atmospheric pressure. The operation is conducted in the manner described above until the chamber 20 is nearly filled with coke. The vapors produced in the coking operation are passed by pipes 29 and 30 to the manifold 18 and inlet pipe 19 of the chamber 20 next to be used. Since the temperature of the outgoing vapors under the conditions indicated above is quite high, for example around 750 to 800 F., the second chamber 20 is thoroughly preheated thereby. After passing through the second chamber 20, the vapor passes by pipe 22 into the fractionating column 23 wherein it is fractionally condensed as described above. The yields of products expressed in percentages by weight on the crude oil are as follows:

Dry gas 1.37 Gasoline 3.98 Clean charging stock 19.55 Coke 3.01

The coke is slightly more porous than that formed in the ordinary atmospheric pressure batch coking operation and can be readily removed by hand tools or other suitable means after the bottom 32 is removed, or through the manhole 34.

Although the invention has been described in connection with the details of its application to a particular type of operation and to a specific example of such operation, it is not intended that such details shall be regarded as limitations on the scopeof the invention, except in so far as included in the accompanying claims.

I claim:

1. The method of distilling hydrocarbon oils which comprises passing a stream of heated oil undergoing distillation into an enlarged chamber wherein vapors are evolved, passing the vapors portion of the vapors, from said chamber to a second enlarged chamber thereby preheating the animals same, and thereafter diverting the said stream of heated oil from said first-named chamber and passing the said stream of oil to said preheated second chamber.

3. The method of distilling hydrocarbon oils which comprises passing a stream of heated oil undergoing distillation into an enlarged chamber wherein vapors are evolved, passing vapors from said chamber into a fractionating tower,' diverting a portion of the vapors from said chamber to a second enlarged chamber thereby preheating sion temperature for a substantial period of time,

hot vaporousproducts being withdrawn from said chamber and normally passed to a fractionating tower, and the said highly heated oil-stream flowing to the said selected chamber being subsequently interrupted and passed to another selected one of said reaction chambers wherein it remains for a substantial period of time, the step of diverting hot vaporous products from the firstnamed selected chamber to the second-named selected chamber while said oil-stream is being passed to the first-named chamber, whereby the said second-named chamber is preheated prior to interruption of flow of the oil-stream to said first-named chamber and its passage into the said second-named chamber.

5. The method of converting hydrocarbon oils which comprises heating a substantially continuously fiowing stream of oil to conversion temperature and passing it to one of a pair of reaction chambers wherein it is permitted to undergo substantial conversion, withdrawing hot vaporous products from said chamber and normally passing them to a fractionating tower while maintaining the other reaction chamber in a relatively cool condition, interrupting the flow of said oil-stream to said first-designated chamber after a predetermined period of time and passing the oil to the other of said chambers, and diverting hot vaporous products passing to the fractionating tower from said first-designated chamber to the other chamber prior to interruption oi the flow of the heated oil-stream to said first-designated chamber and its passage to the said other chamber, whereby the latter chamber is preheated to a substantially high temperature before said highly heated oil-stream is passed thereto. 4

6. The method of treating a petroleum residue to produce coke that comprises heating a confined stream of such residue to a coking temperature, causing said stream to move at a sufficiently high speed to substantially avoid the deposition of coke, passing said stream at coking temperature into an enlarged coking chamber maintained at coking temperature without the application of external heat thereto and wherein conversion to a coke residue occurs, normally passing the stock from hydrocarbon oil residues while producevolved vapors to a fractionating tower wherein fractionation occurs, diverting the confined stream of highly heated residue into a second enlarged coking chamber and directing hot vapors from the first named coking chamber to the second prior to diverting the confined stream of oil thereto to thereby preheat said second chamber to a temperature approximating the desired coking temperature.

'7. The process of distilling hydrocarbon oil to coke and distillate oil as final end products, which, when carried out in apparatus including a plurality of enlarged coking chambers adapted to be used one at a time for coking, comprises supplying a stream of oil heated to a coking temperature to one of said chambers, retaining all of the unvaporized portions of said oil within said chamber to reduce the mass of unvaporized liquid within said chamber to a coke residue, passing vapors liberated in said coking chamber unaccompanied by unvaporized liquid from said chamber through a second coking chamber thereby preheating the same, withdrawing said vapors from said second chamber after passage therethrough and condensing them to obtain distillate therefrom, and thereafter diverting said stream of heated oil from said first mentioned chamber and supplying it to said preheated second chamber for coking therein.

8. The process of distilling a residual hydrocarbon oil to coke and distillate oil as final end products, which, when carried out in apparatus including a pipe still and a plurality of enlarged coking chambers adapted to be used one at a time for coking, comprises passing a stream of such oil 113 through said pipe still and heating it therein to a cracking temperature while causing said stream to move at a sufiiciently high speed to avoid substantial deposition of coke within said pipe still, delivering the heated oil to one of said chambers, 5 retaining all of the unvaporized portions of the oil within said chamber to reduce the mass of unvaporized liquid within said chamber to a coke residue, passing vapors liberated in said coking chamber through a second chamber not receiving liquid oil from said pipe still thereby preheating the same, withdrawing said vapors from said second chamber after passage therethrough and condensing them-to obtain distillate oil therefrom, and thereafter diverting said stream of heated oil from said first-mentioned chamber and supplying it to said preheated second chamber for coking therein.

9. An apparatus for producing clean cracking ing a relatively small amount of coke, comprising a pipe-still, means for forcing residue therethrough, a plurality of vertical chambers provided with removable bottoms, a transfer manifold for each chamber adapted to receive heated residue from said pipe-still for delivery to said chamber, a plurality of valved connections between each of said manifolds and the corresponding chamber at different levels thereof, a condenser means ior conducting vapors from the several chambers to said condenser and a vapor manifold adapted to receive vapors from any one chamber and supply same to any other chamber to preheat same.

ERNEST w. THIELE.

CERTIFICATE or CORRECTION.

Patent No. 1,947,319. February 13, 1934.

ERNEST W. THIELE.

it is hereby certified that error appeers in the printed specification of the above numbered patent requiring correction as ioliows: Page 2, after line 14, insert the words ignited in any suitabie manner. Care must be; and that the said Letters Patent should be read with this correction therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 20th day of March; A. D. 1934.

F. M. Hopkins (Seal) Acting Commissioner of Patents.

Images