US1622703A - Dephlegmator - Google Patents

Description

March 29 1927.

J. A. CAMPBELL DEPHLEGMATOR Filed July 5o, 1925 ,2 sheets-Sheet 1 March 29, 1927. 1,622,703

J. A. CAMPBELL DEPHLEGMATOR 'Filed July 3dJ 1925 2 Sheets-Sheet 2 PATENT OFFICE.l

JULIAN A. CAMPBELL, or LoNe BEACH, CALIFORNIA.'

DEPHLEGMATOR.

Application filed July 30, 1925. Serial No. 46,972.

This invention has to do with devices commonly known as dephlegmators, whose function is to separate the liquid or condensate, or condensable vapors from gases or vapors. Such 'apparatus is used for the separation of liquids or condensates car-.V

ried in or along with uncondensed vapors and gases, in operations upon petroleum oils.

Such operations are sometimes carried on in distillation or cracking treatment of petroleum oils, and sometimes, for instance, in processes for obtaining light hydro-carbons from natural gas. The particular dephlegmator herein shown and described has been designed specifically in connection with a plant for recovering light hydro-carbons lsuch as gasoline from casing-head gas; but

it will be understood that such use is not a limitation upon the apparatus and that the apparatus may be put to other uses as desired; in fact, such specific use involves no different functions as over other uses. a generalv object of the invention to provide a very simple form of dephlegmator in which a mixed body of gases and vapors may be subjected toa comparatively slow cooling that is as perfectly gradual and uniform as possible; thel substances being handled in such a way' that the liquid condensate may settle and 'stratify out of the uncondensed vapors and gases and may then be completely and cleanlyA separated from those uncondensed parts. A great deal of the' uncondensable products in such a mixture is carried either in vaporous form or in finely divided or atomized suspension; and agitation is to be avoided because such agitation will cause the uncondensed vapors and gases tov pick up and carry volf a part of the liquid. It is, therefore, an object of my invention to avoid agitation as far as possible, to provide a dephlegmator apparatus in which the llow of the various gases,

vapors and liquids is smooth and undisturbed; with the result that the condensate is thoroughly and cleanly separated from the unoondensed vapors and gases.

For the purpose yof explaining my invention, I will asume that a mixed body of vapors andI gases (most such bodies contain some fixed gases) is delivered to the de- `phlegmator apparatus at a temperature substantially high enough to keep all the conr `form. I shall then explain how my ephlegmator appa- It is ratus cools the mixed body and so handles the condensate and gases or uncondensed vapors in such a manner as to cleanly separate alllcondensate, whether in liquid form or in the form of mist. For this purpose I illustrate in the accompanying-'drawings a preferred and specific embodiment that is illustrative of the invention, reference for this purpose being had'to the accompanying drawings, in which:

Fig. 1 is a plan of the dephlegmator apparatus;

Fig. 2 is a fragmentary sidi` elevation thereof;

^Fig. 3 is a fragmentary enlarged plan;

Fig. 4 is a fragmentary enlarged horizontal section on line 4-4 of Fig. 2; and

ig. 5` is a vertical longitudinal section on line 5-5 of Fig. 4.

Although I here give a description in full detail of this specific and preferred embodiment of my invention,.it will be understood that this is not done for the p urpose of limiting the invention except as may be expressly stated in lthe following claims;4

but that I give this description in detail so that others may understand the invention itself through having 4a complete understanding of one form of the invention.

A flat and relatively shallow trough 10 is provided with a central. partition 11 that extends from one end 12 of the trough toa point somewhatshort of the other end 13. At end 12 there are two pipe headers 14 and 15 into which several circulation pipes 16 are connected; header 14 forming an entry head for the pipes and header 15 a delivery head for them. The circulation pipes 16 lie horizontally in the trough, somewhat above its bottom and supported at intervals upon suitable sup orts 17, so that the cooling water that come into contact with the pipes completely around them. The pipes extend from header 14 to points near end. 13. of the trough and then turning` acrossv theend extend back the whole lengthof the trough to header 15.

The mixed va rs and gases are delivered to header 14 t rough pipe 20 and flow through the circulation pi throu h the trough and'bac to header 15, thus aving a total flow. of ap oximately twice the length of the `trough. Coolin water isw introduced to'the trough throug ows in the trough mayl s 16 around no i Cil

a pipe 21 at or near delivery header 15 and this cooling water flows to the far-end of the trough at one side of partition 11 and then Hows back toward the other end at the opposite side of the partition. The trough is set preferably substantially'7 level so that when the device is in operation there is always in the trough a body of water covering the circulation pipes. In the form and arrangement of apparatus here shown, I use no outlet for the water, the water being dissipated by evaporation, chiefly at and aroundthe hotter ends of the pipes where the hot vapors and gases are first introduced. This zone of largest evaporation is at the place substantially furthest removed' from the point of introduction of water, s0 that the removal of water by evaporation and the constant addition of lwat-er througlr pipe 21 causes a slow and very uniform fiow of the water ina direction appositeto the fiow of gases and vapors. The cooling water is, therefore, always hottest at the' ointwhere the gases and vapors are first lntroduced and due to its very gradual and uniform flow the water temperature is uniformly graduated between these two points. Consequently the temperature of the vapors, etc., in the circulation pipes, they iowing uniformly through these pipes, is highest at the point of first introduction, lowest near the delivery header' 15 and is very uniformly graduated between these two extreme temperatures, cooling4 taking place with the greatest possible uniformity.

The mixed vapors and gases that are introduced at header 14: may be uniformly distributed between the several circulation pipes 16 if the apparatus is working at full capacity; yor if it is desired to work the apparatus at less than full capacity, at least some of the pipes l6rmay be provided with valves 16 so that some of the pipes may be out off. At whatever capacity the apparatus is working, it is desired that the flow of vapors, etc., through the circulation pipes shall be comparatively slow so as to avoid as far as possible all agitation. Also it will be noted that circulation pi es 16 are so arranged that whenthe con ensate is gradually formed in the pipes, it will drop to the bottom of each pipe and flow undisturbed along its bottom to the end of the pipe. I here are no vertical turns, coils, or the like in these pipes that tend to remix the condensate with the uneondensed vapors and gases once the condensate is dropped out. Eonsequently as the gases and vapors move through the pipes and are gradually and uniformlycooled, the condensatev is gradually dropped out of the vapors and gases and flows in increasing quantity along the bottoms of the pipes; and when the two parallel streams of condensate and gases and vapors in each pipe reach header 15, they move smoothly and evenly into the header, the condensate occupying the lower portion o f that header and the gases and vapors the upper portion.

The temperatures at which the gases, vapors and condensatef are delivered into final header 15 lwill depend upon various factors, among which are the temperatures at which the gases and vapors are delivered to initial header 141, the time period during which the gases and vapors traverse the circulation pipes, and the amount of water continuously su plied to the water feed end of the device. ater may, of course,`be fed fast enouglrltomore than supply the water evaporated, with the result that the pan may be constantly overflowing. In this way' lower final temperatures may be attained; but I find 1n the'usual cases that a water v'supply such as will just about offset the water evaporationv is sufcient to obtain the temperature desired. rlfhe temperature at the final header 15 will, of course, alwaysy into final header 15 the condensate will occupy the lower part of the header without being agitated into admixture with the gases and uneondensed vapors. The exact nature of the condensate will, of course, depend upon the temperature maintained at header 15; but whatever that temperature .may be, by far the larger part of the matter condensable at that temperature passes into and through the header in liquid form. Ve'ry liittle of the condensable matter is carried by the gases and uneondensed vapors in the form of mist.

The outlet Apipe 25 that leads from header 15 to separator 26 preferably leads from the bottom of header 15 as is shown in F ig. 2, so that the liquids may flow directly and smoothly into the separator, the gases and uneondensed vapors flowing along with them. rlhe discharge of pipe 25 into the separator is through an opening 27 having an associated deiector 27 so that all the liquids, gases and vapors are discharged tangentially along the inner surface of the cylindrical wall of the separator and are put into a whirling motion around that wall. rlhe separator inlet 27 is near the upper end of the cylindrical separator shell, and the liquids as they1 whirl also move toward the bottom. By reason of did'erence in specific gravities,' the liquids go to the outside against the c lindrical wall while the gases go to the insi e; and the gases are constantly being passed through a screen wall 28 located in the center of the separator. rlhis screen wall is formed'by wrap ing several convolutions of screen around tli'e nipple or other cylinder 29 that has slots 30, this nipple or cylinder being mounted on and does not extend tothe bottom o the separator shell so that the bottom is left open `for accumulation of liquid which then passes out through final liquid outlet 32.

It will beobserved that the body of gases,

lvapors and liquids that is passed from header to the separator is sub'ected to as little agitation as possible. ere the fluids pass through pipe and come to inlet 27, the liquids are, of course, at that point on the bottom, while the ases and uncondensed vapors are' above. ut immediately upon being thrown into circular motion the liquids are thrown in a body to the outside while the gases and uncondensed va rs are pipe 31,

thrown in aI body to the inside. hatever mist or finely divided'liquid particles the gases and vaporslmay carry are also 'mechanically thrown' to the outside into the body of liquid; and the screen wall, preferably formed of a number of layers of relatively fine mesh screen, also gathers and separates any mist that may be present in the gases and vapors passingto the outlet The mlst particles accumulating upon the screen flow down the screen into the body of liquid at the bottom of the separator. As a conse uence, the gases and vapors finally emerging from the separator are cleaned of all liquids condensable at the lowest temperature maintained in the apparatus. For the purpose of maintaining a uniform temperature, thermometers may be installed in the upper part of the separator at T; and these may well be in the form of thermo-couples from which wires 35 (see Fig. 2) may run to an indicating instrument.

I claim: l

1. In a dephlegmator, a relatively long and shallow pan having a central partition extending from one end to al int somewhat short of its other end, hea ers in the first mentioned end of the pan at opposite sides of the partition, a plurality of circulation pipes extending from one header the length of the pan, crossing the end of the pan and extending back the len h of the pan to the other header, the pan ing arranged horizontally and the pipes extending horizontally from one header to the other, means to introduce vapors to one header, means to remove vapors and condensate from the other header, and means to introduce cooling liquid to the pan at a ointnear the second mentioned header to ow toward the other end of the pan on one side of the partition and ,then back toward the first mentioned end of the pan on the opposite side of the partition, and a separator embodying a vertical tubular shell with a tangential opening near its upper end communicating with the second mentioned header, and a-gas and vapor outlet at the center of the shell, said gas and vapor outlet embodying a central slotted pipe with a surrounding screen wall composed of a plurality of layers of screen.

2. In a dephlegmator, a relatively long and shallow pan adapted to contain'a cooling liquid, vapor circulating pipes arranged substantially horizontally in the pan and adapted to be covered by cooling liquid, means to introduce vapors to said ipes at one end, an outlet leading horizontally from the other ends of the pipes, a separator embodying a vertical tubular shell with a tangential inlet near its upper end communieating directly with said outlet, a central outlet for gases and vapors in the shell, and all: outlet for liquid at the lower part of the s ell.

In witness that` I claim the foregoing I hafe hereunto subscribed my name this 10th day of July, 1925.

JULIAN A. CAMPBELL.

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