US2177517A - System for handling an emulsion - Google Patents

Description

Oct. 24, 1939. A E CUTHRELL 2,177,517

SYSTEM FOR HANDLING AN EMULSION Filed June 17, 1938 Patented Oct. 24, 1939 "UNITED STATES PATENT oFFlcE 2 Claims.

The present invention is directed to a positive displacement fluid pump to be operated on the principle of displacement of liquid by gases. The principal object of the present invention is the provision of a, simple, automatic, inexpensive pump to be used for the pumping of liquids wherey a liquid head is available and high pressure'ga'sA can be provided. In the particular embodiment `hereinafter described the pump of the present invention is shown applied to oil well operation.A It is apparent, however, that the pump is of general utility and is especially adapted .for use as a sump-pump for sewage disposal andffor ther transfer of any liquid from a reservoir in which there is a liquid head to a different location.

In the accompanying drawing, Figure 1 shows the'y pump of the present invention schematically in an arrangement employed at oil wells for treating emulsions of oil-in-water.

Figure 2 shows the pump of the present invention in diagrammatic form in a borehole in which it is employed to 'pump oil to the surface.

In the production of oil a greatv deal of water is also produced', usually in the form of a waterfin-oil emulsion. Before the oil is fed into pipe lines, it becomes necessary to break this emulsion. This is usually accomplished by treating the emulsion lwith a" so-called demulsifying agent which separates the oil from the emulsion. This vdemulsifying operation is usually carried out at an elevated temperature so'that the conventional apparatus employed for this operation is a separating tank, a heater and a pump for circulating tubing from theoil well.` Pipe line oil is drawn off from the separator by line 3. An outlet pipe 4 is conectedto the bottomof the tank and also to a heating coil, not shown, arranged in heater 5, said coil having an outlet pipe 6 which is provided with a ap valvey 1 at a point just prior to its. connection with a `tank 8. Flap valve 1 is so constructed as to permit the iiow of liquid through pipe 6 only into tank 8. On the opposite side of the bottom of tank 8 is an outlet pipe 8 provided with a ap valve I0. The other end of pipe 8 is connected to the gun-barrel 2 above the separating tank. The iiap valve III is so constructed that the flow of iiuid through pipe line 9' can take place only from tank 8 to the gunbarrel.

Tank 8 is'av closed chamber provided at its 5 top with a packing gland I I in which is arranged a rod I2 which extends into tank 8 to a point near its bottom. The upper end of rod I2 outside of tank 8 extends into a small chamber I3 which is connected to tank 8 by a pipe I 4. Chamber I3 is provided with an inlet pipe I5 connected to a source of high pressure gas, (not shown), and an outlet pipe I6 for gas. Carried by the rod I2 and arranged in the chamber I3 are a pair of pistons I'I and I8 which are spaced apart a distance greater than the distance between pipes I5 and I6, and so related to each other that when piston I1 covers outlet I6, piston I8 is above inlet I5, and when piston I8 covers inlet I5, piston I'I is below outlet I6. Arranged in chamber 8 is a iloat I9 provided with a central passage 20 which is adapted to encircle the rod I2, whereby the float I8 is guided by the rod I2 but can float freely with respect thereto.. Near the upper end of chamber 8 rod I2 is provided with a stop 2l, and near the lower end of chamber 8 it is provided with a stop 22.

The operation of the arrangement shown in Figure 1 is simple and automatic. An emulsion is fed into the separating tank I by gun-barrel 2 at a rate such as to keep a head even with outlet pipe 3. In practice, the demulsifying agent isusually fed in with the oil or added directly to the tank. The outlet valve on outlet 3 can be kept in closed position until a layer of pipe line oil collects in separating vessel I. This layer will not be disturbed by the circulation in the arrangement shown. As can be seen from the drawing, the head of liquid in tank I is higher than the head of liquid in tank 8 and will be continuously maintainedA so.

With the parts in the position shown in the drawing, the tank 8 is filled with liquid and the oat I8 has just actuated the rod I2 so as to move piston I8 off the inlet opening I5 and to move piston I'I onto the outlet I6. High pressure gas is, therefore, let into chamber 8 through inlet pipe I5 and connection I4, forcing the liquid in chamber 8 out through pipe 8 into the gunbarrel. When the liquid level drops to the point 50 where the float I9 rests on stop 22, the weight of the float carries the pistons I1 and I8, which are normally held in any given position by friction, down to a position where the outlet pipe I6 is opened and the inlet pipe I5 is closed. This 55 permits the head of liquid in chamber I to force liquid through pipe 4 and pipe 6 through nap valve 1 into chamber 8, lifting the float H-ll which follows the level of liquid until it contacts the stop 2| and again operates the pistons so as to permit the introduction of' high pressure gas in chamber 8 and start the cycle again. It is to be noted that flap valve IU does not open when flap valve 1 opens to admit liquid into chamber 3 because of the head of liquid in pipe 9 over flap valve l0.

Once the pumping is started and a layer of pipe liney oil is established in separato-r l, the operation` is automatic and pipe line oil can be drawn continuously from separator l. It is apparent that more than on-e tank 8 can be employed and operated in such a phase relation that the operation is continuous. For example, with a. second tank 8, the line 6 will be branched and line 9 will be branched to have a connection with each tank, and the floats will be so regulated that one tank is exhausting gas while the other tank is exhausting liquid. Alternatively, a pluralitT of tanks 8 can be employed to operate in unison so as toincrease the capacity of the unit.

In the arrangement shown in Figure 2, numeral 23 designates the casing in an o-il well, and numeral 24 designates the tubing which conducts the oil to the surface. The `tubing is of such a length as to extend well below the head of oil in the casing which is indicated for illustrative purposes as a dotted line 25. A flap valve 2E is arranged in the lower end of the tubing in such a manner as to permit the flow of fluid only upward through the tubing. v

A chamber 21 is secured to the tubing by a threaded connection at its upper end, or in any o-ther fashion, in such a manner that the lower end of the tubing extends nearly to the bottom of the chamber. Mounted on the top end of the chamber 21 is a packing gland 28 in which. rides a rod 29 which is shown to be oifset so as to lie close to the side of the chamber throughout its length. Secured to the lower end of the rod v near the bottom of the chamber is a disc 30 perforated to embrace tubing 24. A similar disc 3l is xed to rod 29 near the top of chamber 21. The upper end of rod 29 outside of chamber 21 extends into a small chamber 32 which is provided at its upper end with an inlet pipe 33 and at its lower end with an outlet pipe 34. Intermediate these pipes is a second outlet pipe 35 connecting chamber 32 to the upper end of chamber 21. Carried by rod 29 are a pair of pistons 3G and 31 respectively adapted to ride in chamber 32 and cover the entrances to pipes 33 and 34 respectively.

A iioat 38 is arranged in chamber 21 and is of such a-form as to encircle tubing 26. This iioat is adapted to cooperate with stops 30 and 3l to actuate the pistons 36 and 31. The lower end of chamber 21 is provided with a flap valve 3S so arranged as to permit the ow of fluid only from the casing into chamber 21.

The operation of the arrangement shown in Figure 2 is much the same as that shown in Figure l. With the parts in the position shown, the chamber 21 is lled with liquid and float 38 has just actuated pistons 36 and 31 so as liquid level becomes low enough for the float` 38 to rest on stop 30, the weight of the float actuates the pistons so as to close inlet pipe 33 and open outlet pipe 34. the liquid level in the casing causes flap valve 39 to open to permit the flow of fluid from the casing into chamber 21 until the float 38 again,

contacts stop 3l and again actuates the pistons to start the cycle over. During the flow of iiuid fromv the casing into chamber 21, fluid is prevented from entering the tubing 24 by reason of the liquid level in the tubing over s the flap valve 23.

It will be apparent that the specific embodiments described above are merely illustrative of the forms which the present invention can take.

When this happens, f

It is evident that any one of anumber of com- 4 monly known typesfof valves can be substituted for the piston arrangement shown in the embodiments. Oneobvious alternative is the use of a rotating valve operated with a rod and pinion, the pinion being fixed on the rshaftV o-f the rotating valve and the rack being at the upper end of the rod i2 in Figure 1. Any number of alternatives will readily suggest themselves to one skilled in the art. Likewise, changes may b-e made in the relation of parts to each other and in the size of parts Without departing from the principle of the invention.

It is to be understood, therefore, that the present invention is not limited to the specific forms herein illustrated and described, but contemplates any apparatus utilizing the principles of operation upon which the specific embodiments shown are based. In the appendedl claims it is intended to claim the presentl invention as broadly as the prior art permits.

I claim:

1. A system for handlingv an emulsion of oil and water lcomprising a reservoir for said emulsion, a chamber carrying a float arranged below said reservoir, a conduit connecting the bottom of said reservoir with said chamber, a heater.` in said conduit, a source of high pressure gasA connected to the upper end of said chamber, a

valve mechanism controlled by said float adapted to control the feed of gas to said chamber in such a yway as to admit gas into said chamber when the liquid therein reaches a predetermined height and to shut off the supply of gas when the liquid in said chamber drops to a predetermined level, a conduit for returning iluid from said chamber to said` reservoir and an outlet for oil arranged adjacent the top of said reservoir. 2. A system, according to the preceding claim, in which the conduit for returning fluid from the chamber to the reservoir delivers the fluid at a point adjacent the bottom of the reservoir. ANTUM E. CUTHRELL.

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