US1951497A

US1951497A - Oil distillation

Info

Publication number: US1951497A
Application number: US499623A
Authority: US
Inventors: Wallis John Samuel
Original assignee: Foster Wheeler Inc
Current assignee: Foster Wheeler Inc
Priority date: 1930-12-03
Filing date: 1930-12-03
Publication date: 1934-03-20
Anticipated expiration: 1951-03-20

Description

March 20, 1934. 1 s, wALLls 1,951,497

OIL DISTILLATION Filed Dec. '3. 1930 x f 1f l /9 I l 39 i g/ l/I292. 3.

ATTORNEY Patented Mar. 20, 1934 UNITED STATES PATENT CFFI-CE OIL DISTILLATION Application December 3, 1930, Serial No. 499,623

4 Claims.

My invention relates to oil refining apparatus.

My invention contemplates the provision of a novel combined condenser and vacuum run-down tank in a single unit. The combined apparatus A preferably also includes a separator. Heretofore it has been the practice in this art to construct the vapor heat exchangers, the vapor condenser, the separator in the hot well of the vapor condenser, the barometric condenser and the vacuum run-down tank as separate pieces of equipment.

This necessitates separate supporting steel structure, connecting conduits, large space requirements and the accompanying expense necessitated by building separate items and assembling all of these items to make a unit system. I propose to combine various of these parts and particularly the barometric condenser and the vacuum rundown tank in a single unit, thus reducing the number of separate units required and the attendant disadvantages.

Further objects and advantages will appear from the following description considered in connection with the accompanying drawing, which is to be considered a part of this speciiication, and

on which:

Fig. 1 is a View, partially in cross-section, showing a preferred embodiment of my invention;

Fig. 2 is a cross sectional View taken o-n the line 2 2 of Fig. 1; and

Fig. 3 is a cross-sectional view taken on the line 3-3 of Fig. 1.

Referring more particularly to Fig. 1, reference character 10 designates a vapor conduit leading from a vacuum fractionating tower 9 or the like. Conduit 10 communicates with a vapor heat eX- changer 11 which is connected by means of a conduit 12 with a surface condenser 13. Heat exchanger 11 is supplied with a cooling medium, preferably crude oil, through a conduit 14. Oil,

after having been in heat exchange relation with the vapors admitted through conduit 10, is discharged through a conduit 15 and may be supplied to a heater, such as a tube still, and thence passed into the tower 9. A cooling medium, such as water, is supplied to surface condenser 13 through a conduit 16 and is discharged therefrom through a conduit 17. Y

A conduit 18 connects the lower part of surface condenser 13 with the more central portion of a preferably cylindrical shell 19. Shell 19 and the structure contained therein to be described hereafter, constitutes the combined condenser, separato-r and vacuum run-down tank.

Disposed within shell 19 at a point above the point where conduit 18 communicates with-the (Cl. IBG-114) shell, is an entrainment separator 20 which serves to separate oil condensate from steam. Separator 20 may, as shown, consist of two rows of obliquel'y disposed plates, of opposite angularity in the dii"- ferent rows. Above separator 20 is located a' liquid receiving member 21 which occupies the greater portion of the cross-section of the shell but to one side of which there is a passageway 22. A baromet-ric tube 23 communicates with the in'- terior of shell 19 within the member 21 and ektends downwardly for a distance sufficient to balance the difference of pressure between theoutside and inside of theY shell and preferably yat least thirty-two feet. ,Near the upper part of shell 19 is a liquid distributing device 24' whichV comprises a cone-shaped member having ahorizontal flange 25, the outer periphery of Whichi's secured to the interior of shell 19, and a vertical flange 26. Secured to vertical flange 26 is a horizontally spaced annular ring 27 provided with a se- 'I ries of apertures 27 (Fig. 2). Below distributing member 24 there is located a vapor baille andliquid redistributing device designated generally by'reference character 28. Bale 28 comprises' a traylikemember 29 in which is formed a series of converging slo'ts 30. Supported a short distance above tray 29 by means of separators 31 is a cover plate 32 which is provided with a series of converging slots 33 which are arranged so as to be out of alignment With slots 30 in tray 29. T-r'ay 29 does not extend entirely across the interior of shell 19 but there is left a passageway 34 between one side of the tray andthe shell. A second vapor baille and liquid redistributing device 35 is located below baille 28 and is similar thereto'except that it is placed so that the passage 36 therearound is on the opposite side of the shell from the passage 34. While I have shown two baffles, it is apparent that a greater or a lesser number might be employed. Regardless .of the number of baffles employed, they should be so arranged that the passageways betweenladjacent devices and the shell 19 and between the lowermost device and liquid receiving member 21 occur on opposite sides of the shell to provide a tortuous passageway for ilow of gas. A baille42may be provided to ensure that all the Water passes into member 21.

A conduit 37 communicates with the upper part of shell 19 and leads to some form of vacuum producing apparatus, such as a steam jet vacuum pump 8. A conduit 38 communicates withthe bottom of shell 19 and leads to storage. `If the storage tank is located at adistanc'e below the bottom of shell 19 corresponding to vacuum mainlio ` lower pressure existing within the shell.

steam which passes upwardly withinthe shell is vvbrought into intimate contact with the rain of tained or other liquid column means is used to balance the vacuum, it is not necessary to insert a pump in conduit 38. Otherwise a pump is necessary in order to force the liquid to the storage tank against the vacuum existing within the shell. A conduit 39 communicates with the lower part of shellv 19 and leads preferably to a reilux pump. A liquid level regulator 40 is provided for assuring a minimum volume of liquid in the lower part of the shell. This is indicated. diagrammatically by the float 40 controlling valve 41 in pipe 38 and operating to prevent the liquid level falling below a predetermined minimum by closing valve 41 when the liquid falls to this level.

The above described apparatus operates as follows:

A mixture of oil vapor and steam is drawn through conduit 10 from the upper part of the fractionatng tower 9 due to the lower pressure produced within shell 19 by the ejector 8. The oil and steam vapors pass through heat exchanger 1p1 where their temperature is reduced by reason of the fact that they are brought into heat exchange relation with cold crude oil introduced from storage through conduit 14. The vapors thus somewhat cooled pass from heat exchanger 11 through conduit 12 to surface condenser 13 where they are brought into heat exchange relation with cooling water introduced through conduit 16. Here the temperature of the vapors is reduced sufficiently to cause condensation of the oil but not condensation of the steam. The liquid oil and steam pass directly from condenser 13 through conduit 18 into the central portion of shell 19. Herethe liquid oil passes downwardly to the lower part of the shell into what may be termed the run-down tank section. The steam passes upwardly within the shell and through separator 20 which functions to remove entrained particles of liquid oil. The steam passes upwardly in a tortuous path around liquid receiving member 21 and

baiiies

35 and 28 and through the cone-V shaped distributing device 24. Cooling water is admitted to the distributing device 24 through conduit 43 and passes through the apertures 27' formed in annular ring 27 and falls in the form of a cylindrical curtain ofwater onto baffle 28. The water strikes cover plate 32 and passes through apertures 33 therein and thence passes through apertures in tray 29 which are out of alignment with apertures 33 and is t-hus redistributed and falls to baiile 35 where the redistributing operation is repeated. The cooling Water falling from baffle 35 is collected in liquid receiving member 21 and passes through barometric tube 23 to waste. The

horizontal battles

35 and 28 may be constructed to direct the downflowing water into member 2l or one or more separate baffles such as 42 may be provided for this purpose or both may cooperate in this function. All the downflowing water should beY directed into member 21 so as not to fall into the body of liquid oil in the bottom of the shell.

Inasmuch as the bottom of barometric tube 23 is at a level below the level of liquid receiving member 21 which allows a head of liquid to be maintained therein of suiiicient height to balance the vacuum maintained in the shell, water Vwill flow by Vgravity through this tube against the The cooling water dropping from the distributing de- Vice 24 and the

baffles

28 and 35 and is thereby condensed. The condensate is collected with the cooling water in liquid receiving member 2l.

The non-condensable gases, as air, which are admitted into the shell 19 are removed therefrom through conduit 37 which is connected to steam jet vacuum pump 8 which thus maintains the vacuum within the shell. A portion of the oil which is accumulated in the run-down portion of shell 19 passes therefrom through conduit 38 to storage. The remainder of the oil here accumulated passes through conduit 39 to a reiiux pump from which it is pumped into the upper portion of the fractionating tower to serve as reflux liquid. Liquid level regulator 40 prevents a level in the run-down portion of the shell 19 from falling below a predetermined minimum by closing valve 41 if the liquid falls to this level.

It will thus be seen that I have incorporated in a single unit a barometric condenser, the separator which is ordinarily placed in a separate hot well below the condenser and a vacuum run-down tank. This I have accomplished Without allowing the cooling water used in the barometric condenser or the condensate formed therein to mix with the liquid oil collected in the vacuum rundown tank.

While I have shown and described a preferred embodiment of my invention it is to be understood that all modications thereof which would be apparent to one skilled in the art fall within its scope, which is to be limited only by the appended claims Viewed in the light of the prior art.

What I claim is: y

1. Apparatus for the fractional distillation of hydrocarbon oils and the like comprising a fractionating tower, means fo-r condensing the oil vapors issuing with steam from the tower, a shell, means for collecting the condensate of the oil vapors in the shell, means for introducing water into the shell, means for passing the steam counter-current to and in contact with the water to thereby condense the steam and means for Withdrawing the water and steam condensate from the shell.

2. Apparatus for the fractional distillation of l120 hydrocarbon oils and the like comprising a fractionating tower, means for condensing the oil vapors issuing with steam from the tower, a shell, means for maintaining a Vacuum in the shell, means for collecting the condensate of the oil vapors in the shell, means for passing the steam counter-current to and in contact with water in the shell to thereby condense the steam, means for collecting the water and steam condensate in the shell and a barometric tube connected to said water and steam condensate collecting means.

3. Apparatus for the fractional distillation of hydrocarbon oils and the like comprising a fractionating tower, means for condensing the oil vapors issuing with steam from the tower, a shell, means for maintaining a Vacuum in the shell, means for collecting the condensate of the oil vapors in the lower part of the shell, a plurality of superposed trays in the upper part of the shell, means for introducing water into the upper part of the shell and for causing the Water to flow onto and from the trays to provide a curtain of water between the trays, means for introducing the steam into the shell and causing it to flow through the curtains of water to condense the steam and a barometric tube connected to the lowermost tray through which the water and condensed steam are withdrawn from the tower.

4. Apparatus for the fractional distillation of hydrocarbon oils and the like comprising a frac- 157,0

ico

tonating tower, a condenser for condensing the oil vapors issuing with steam from the tower, a shell, a conduit for conducting the oil condensate and steam to the shell, means for collecting the oil condensate in the lower portion of the shell and for withdrawing the condensate therefrom, a plurality of superposed trays in the upper portion of the shell, means for introducing Water into the shell onto the uppermost tray and for causing the Water to ow therefrom successively onto the other trays to provide a curtain of water between