US2337291A - Apparatus for separating the constituents of petroleum emulsions - Google Patents

Description

Dec. 21, 1943.. I G; L. ADAMS ET AL 2,337,291 APPARATUS FOR SEPARATING THE GONSTITUENTS 0F PETROLEUM EMULSIONS Original Filed Aug. 25, 1938 SheetsSheet l 1 j P20 23 25 1 27 -20 L 15 29 28 GALE LADAMS ROY G. BARLOW VENTORS Dec. 21, 1943. G, LADAMS ETAL 2,337,291

APPARATUS FOR SEPARATING THE CONSTITUENTS OF PETROLEUM EMULSIONS Original Filed Aug. 25, 1958 2 Sheets-Sheet 2 GALE L.ADAMS ROY G. BARLOW l/ENTORS Patented Dec. 21, 1943 APPARATUS FOR SEPARATING THE CON- STITUENTS OF PETROLEUM EMULSIONS Gale L. Adams, Los Angeles, and Roy G. Barlow, Whittier, Calm, assignors to Socony-Vacuum Oil Company, Incorporated, New York, N. Y., a corporation of New York Original application August 23, 1938, Serial No.

Divided and this application October i 17, 1939, Serial No. 209,842

2 Claims. (Cl. 252-360) This application is a division of our co-pending I application Serial No. 226,292, filed August 23,

1938, and entitled Method of separating the constituents of petroleum emulsions.

The object of the invention is to continuously separate the phases of a flowing stream of petroleum emulsion after said emulsion has been resolved by the application of an electrical stress or flow.

The art of electrical dehydration is extremely voluminous and great numbers of devices for the application of an electrostatic or electrical effect to emulsions have been proposed. In almost all of these devices the electrodes are submerged in a relatively large body of emulsion which changes in characteristics as the demulsification' applied to a flowing streamof emulsion, these de-v vices delivering a stream in which the emulsion is resolved but the phases are not yet separated, that is to say, a stream of oil containing in suspension the water of the emulsion, in drops and droplets of various sizes.

These flow-stream treaters labor under the dis advantage that, no matter how complete the resolution of the emulsion by the electrical effect, the discharged stream contains, not only the oil and water originally present in the emulsion, but also the emulsifying agent; usually a relatively small proportion of some very finely divided solid such as clay, shale, or asphaltic wax. In the presence of this emulsifying agent the resolved phases are this aim I make use of centrifugal force for effecting a rapid separation of the phases in a manner exemplified in the attached drawings, in which Fig. 1 represents the entire apparatus in elevation and partial vertical section;

Fig. 2'is a plan view of the centrifugal unit and Fig. 3 is a section on an enlarged scale of the collectors indicated at'34 and 39 of Figs: 1 and '2.

Fig. 4 is a vertical sectional view through modifiedform of centrifugal unit. 1

Referring to the drawings, the flow stream treater indicated at It! is that described in U. S. Patent 2,092,491 to Adams and Barlow, and reference is made to this patent for details as to the construction and operation of the device. Other forms of flow-stream or pipe-line treaters may be substituted if" desired, as for example that shown in Fig. 2 of U. S. Patent 2,083,800 to William Woelflin, but anytreating means so subpasses out of the zone in which it is subjected to electrical stress, particularly if the stream is brought to a condition of turbulence at any point prior to that at which the emulsifying agent has been removed. In practice it has been found diflicult to introduce the resolved stream into a settling tank without causing a very undesirable amount of reemulsification of the constituents of the stream.

The aim of the present invention is to take the stream of resolution products from a flow-stream electrical treater and to separate or part the oil, water, and emulsifying agent without turbulence and without the danger of reemulsifying the once-resolved products. In accomplishing stituted must'be deprived of any settling tank or other reservoir for treated oil and must be connected to discharge directly into the zone in which the centrifugal force is applied.

The supply of emulsion to be treated enters treater I0 through pipe H and control valve l2, under gravity or pump impulsion and from a source of supply not shown. In the treater the stream is subjected to an electrical stress or flow, as may be, and is thereby resolved, electrical connections being indicated at 13 and M.

The stream of resolution products passes through a pipe i5 to the centrifugal apparatus. This pipe should be of as large diameter as may be convenient, should be smooth inside, and should be free from any sharp turns. tubing bent to long radii is to be preferred to pipe and fittings for this purpose.

Numerous types of centrifuge are available for subjecting the resolved stream to centrifugal force, but I prefer the apparatus generally indicated at i6 as subjecting the mixture of resolu-- tion product to the least possible disturbance prior to separation of the phases.

The specific centrifugal machine indicated at l6 consists of a bowl I! tapering upwardly and, preferably, having a slightly depressed bottom l8. The bowl is suspended in a frame having uprights 2020 connected by an upper spider 22 and a lower spider 23. Centrally of the upper spider is a bearing 2| in which revolves a stub shaft; 24 projected upwardly from the upper end of the bowl. At the center of the lower spider is situated a bearing 25 in which rotates a hollow Steel or copper shaft 26 projecting downwardly from the bottom the bowl. are shown, but in practice frictionless bearings would be used. The hollow shaft; 26 is provided with a pulley 21 or other means for revolving the bowl at the requisite speed.

The end of tube I is directed upwardly within hollow shaft 26 as at 28 and is terminated at the lowermost point of the bottom of the bowl. The portion 28 of the tube should be machined to a free sliding fit within the hollow shaft and a packing box 29 may be provided at the lower end of the shaft to prevent leakage.

Within'the bowl a stiff rod or tube 30 is projected downwardly from the upper end of the bowl and supports a sheet metal cone 3| in a position substantially parallel to the bottom of the bowl. This cone, which revolves with the bowl, is spaced from its bottom by a distance which may more or less equal the diameter-of the inlet pipe 28.

At the extreme outer and lower edge of the bowl we place a water outlet 32 which must be provided with some means for controlling the quantity of liquid flowing therethrough, as for example the valve 33. This outlet connection, which of course revolves with the bowl, discharges into a ring shaped channel 34 suspended from the frame in a fixed position surrounding the bowl. This chan= nel, shown in cross-section and on an enlarged scale in Fig. 3, has a slot 35 in which nipple 32 travels, and an incurved edge 36 to prevent liquid forcibly projected into the channel from being thrown back out of the slot, and is provided with one or more drainage outlets 31.

At or near the upper end of the bowl we provide a similar outlet nipple 38 which discharges into a collecting ring 39 provided with a drainage outlet 40. .This nipple needs no valve control and is preferably extendedinwardly to-the center of rotation of the bowl. 'It'will be understood" that a single outlet or a plurality of outlets arranged unsymmetrically should be counter-baianced'by suitableweights fastened totlie bowl in such position as to bring it into running balance.

This assembly functions in the following manner. oil, and emulsifying agent-produced in treater l0 flows through tube |528 into the space bewater and any solid substances actingg'as' emulsifying agents are forced to the periphery of the bowl from which they are continuously withdrawn For simplicity plain bearings The stream of resolution products-water,

by outlet.32 at. acontrolled. rate. Oil-freed from water by centrifugal force collects in the central and upper portion of the bowl from which it is discharged through nipple 38. This outlet will remove any proportion of the feed which is not withdrawn by valved outlet 32 and consequently needs no control. Solids heavier than water are in part projected against the outer wall of the bowl, and gradually pass downward to the outlet due to the flare of this surface.

In handling crude petroleums of high viscosity it is often necessary to beat them to the atmospheric pressure boiling point of water, or to some lower superatmospheric temperature at which dissolved gases are evolved, in order to render them amenable to electrical resolution and to centrifugal separation. If oils so heated are passed into the centrifuge at atmospheric pressure, the evolution of steam or gas in the bowl interferes very seriously with the separation by centrifugal force.

Insuch cases I prefer to use the modified form of apparatus illustrated in Fig. 4. In this form of the invention the bowl I! is suspended between upper and lower frame members 22 and 23 (of which only fragments are shown) in bearing elements indicated at 2| and 25. To the bottom of the bowl is aflixed a flanged collar 26 carrying a driving pulley 21. 'Inside this collar is fixed a relatively wide tube 4| which revolves with the bowl.

Inside the bowl a circular plate 42, arranged parallel with its bottom, is supported by a plurality of standards 43 and at the center of revolution of this plate is fixed a feed pipe 44 concentrically arranged within pipe 4|. This pipe discharges above plate 42 and below a cone 3| which is supported from plate 42 by a plurality of standards 45.

The feed pipe I5, which is in fixed position, is coupled to feed pipe 44 by any desired form of packed swivel joint 46. A water outlet pipe 41 having a control valve 48, which is held in fixed position, is affixed to a double packed swivel joint 49 inside which pipes 4| and 44 revolve. An oil outlet pipe 5|, which is illustrated as forming the upper support for the bowl, is projected upwardly from the top of the bowl and is coupled to an oil discharge pipe 52, held in fixed position and provided with a control valve 53, by means of a packed swivel joint 54 inside which pipe 5| revolves.

In the use of this form, which may be main- 5 tained under any desired pressure by regulation of valves 48 and 53, the mixture of oil and water enters the bowl above plate 42 and below cone 3|. Separated water returns from the periphery of the bowl beneath plate 42 to pipe 4| by which it is discharged into wateroutlet pipe 41. Separated oil is withdrawn from the upper end of the conical bowl through pipe 5| by which it is discharged into oil pipe 52.

We claim as our invention:

1. Apparatus for separating the constituents of a loose mixture of oil and water, comprising; a substantially closed vessel having a fiat bottom; means for maintaining said vessel in rotation on its vertical axis; an axial inlet tube for said mixture of oil and water extending a short distance into said vessel from the bottom; an axial oil outlet tube fixed to the upper endof said vessel; an axial water outlet tube placed around said inlet tube and ending at the bottom of said vessel; a' partition attached to the upper end 0? said inlet tube, setting off between itself and the bottom of said vessel a spacencomniunicating only with the peripheral region of the re mainder of said vessel and with said water out let tube; a spreader plate setting off between it? self and said partition a substantially unob structed, approximately disc-shaped space having a thickness similar to the diameter of saiki inlet tube, said plate having its periphery in t a radially intermediate region of said vessel; a sta-= tionary water pipe and a swivel joint connecting it with said water outlet tube; a stationan g oil pipe and a swivel joint connecting it with said oil outlet tube; and adjustable valves in said stationary oil and water pipes for maintainingfa desired back pressure in said vessel.

2. In an apparatus for the separation of co 1 stituents of a petroleum emulsion includi ad means for electrically treating a flowing strea a i I f i v a centrifugal separator for and water phases and means emulsion from said electrical of said emulsion,

separating the oil to conduct treated treating means to onduit Withdrawing oil and water GALE L. ADAMS. ROY G. BARLOW.

Images