US2056763A

US2056763A - Apparatus for treating petroleum emulsions

Info

Publication number: US2056763A
Application number: US47503A
Authority: US
Inventors: George S Bays
Original assignee: Stanolind Oil and Gas Co
Current assignee: Stanolind Oil and Gas Co
Priority date: 1935-10-30
Filing date: 1935-10-30
Publication date: 1936-10-06
Anticipated expiration: 1953-10-06

Description

Oct. 6, 1936. G. s. BAYs APPARATUS FOR TREATING PETROLEUM EMULSIONS 2 Sheets-Sheet l Filed 0G13. 30,

Oct. 6, 1936. G, s, BAYS APPARATUS FOR TREATING PETROLEUM EMULsIoNs Filed Oct. 30, 1955 2 Sheets-Sheei'l 2 Patented Oct. 6, 1936 UNITED STATES PATENT OFFICE APPARATUS FOR TREATING PETROLEUM EMULSIONS This invention George S. Bays, Tulsa, Okla., asslgnor to Stanollnd Oil and Gas Company, Tulsa,' Okla., a

10 Claims.

relates to an apparatus for treating or breaking petroleum emulsions, particularly emulsions of crude oil and brine such as are encountered in the oil fields.

Petroleum emulsions, and particularly oil field l emulsions, are in many cases very stable and considerable difficulty is often encountered in treating or breaking them to remove the water or brine. Many methods have been proposed and used in the past for treating such emulsions with varying degrees of success. of my invention to develop a peculiarly eicient It is an object and inexpensive apparatus for accomplishing this purpose.

Other and more detailed objects of my invention will become apparent as the description thereof proceeds.

I have experimented with a great variety of different processes and apparatus for breaking emulsions and have found that the best results can be obtained by rolling the emulsion in thin lms or discrete globules through a body of water in contact with a wooden surface.

I am

not entirely sure what the reason is for the great success of this method but certain theories in this connection will be set forth hereinafter.

The apparatus of my invention and the process in which it is used will now be more fully described in connection with the accompanying drawings which form a part of this specification and in which Figure 1; and

Figure 5 is a detailed elevation taken along the line 5-5 of Figure 4.

Referring now more particularly to the drawings it will be seen that my apparatus comprises a treating tank II containing a plurality of pairs of troughs. inclined planes or bailies I'I, I8, and I9 arranged at slight angles to the horizontal in zig-zag fashion as shown.

Tank II is normally filled with water to av level above the top troughs I9. v

Water is introduced into treating tank II through valve 20 and pipe 2|.

The level of the water in the treating tank is controlled by means of water leg 22.

Thus when valve 23 is open (Cl. 21o-47) and valve 24 is lclosed the water level in pipe 25 risesas water enters treating tank II and eventually overflows through pipe 26, thereby assuring a constant level of water which should in all cases extend above the top troughs I9. 5 Water accumulating from the treating operation overflows in this same manner. Pipe 21 extends upward and is preferably open to the atmosphere to avoid any possible syphoning effect. The water in treating tank II can be changed as required through valve 20 and/or valves 23 and 24.

When treating tank II has been filled with water a petroleum emulsion, which will normally be of the water-in-oil type and which will normally contain crude oil, water (or brine) and gas is introduced from storage or directly from an oil well through line 28 into gas separator 29 which may be of any conventional type and which may be mounted on treating tank II, alongside it or in any convenient location. The emulsion from which the gas has been separated is then passed through line 30 into my treating tank II. The gas passes oil' from the top of gas separator 29 through line 3| which communicates with the top of treating tank Il through fitting 32. The gas then passes out of the system through line 33 from which it may be fed to the boilers normally used in connection with oil ileld practice or may pass to any other desired equipment.

The reason for separating the gas is to prevent its liberation in treating tank II wherein it would rile up the material being treated and interfere with the efficiency of the treating operation. In order to avoid the development of pressure in treating tank II, and to avoid the gas loss and hazard which would occur if the tank were vented to the atmosphere, the gas line is connected with the top of the tank.

It-will be understood of course that lt is not always absolutely necessary to separate the gas even when it is present. Moreover in; some cases the emulsion may not contain any substantial amount of gas. Thus it is possible to eliminate the gas separation equipment and pass the emulsion directly into treating tank II. In any event the emulsion in treating tank II is directed upward by riser 3l and by its natural buoyancy. 'Ihe emulsion accumulates below distributor 35, the detailed construction of which is shown in Figures 4 and 5. The purpose of this device is to distribute incoming emulsion evenly across the troughs I2. This is accomplished by means of saw teeth 36 through which B5 the emulsion bubbles. Distributor 33 is, of course, closed ,at its ends. The rising bubbles of emulsion contact the lower portion of the bottom troughs I2 and flow upward past saddle 31. This saddle is likewise of saw tooth construction, the saw teeth 38 being somewhat finer and less deep than those of distributor 35, so that coarse distribution is obtained by means of distributor 35 and fine distribution by means of saddle 31. It will be understood that in many cases one or both of these saw toothed elements may be omitted but their presence Vserves to secure better distribution of the emulsion.

Block 39 serves to prevent any of the emulsion from passing upward through the spaces between the various pairs of troughs.

After passing saw toothed saddle 31, the emulsion passes upward through the water along the under sides of troughs I2 andit is at this point that the real treating or emulsion Ibreaking action begins to occur. The emulsion passing upward along the under side of troughs I2 in a thin illm or preferably in discrete globules is subjected to a rolling action and this rolling action tends to break the film separating the oil in the emulsion from the water or brine therein. The rupture of this film promotes the breaking of the emulsion and the water gradually separates out and augments the body of water in treating tank II.

On reaching the upper end of troughs I2 the emulsion passes upward to the under sides of troughs I3 and is prevented from escaping from the trough system by means of drop ends 40.

'I'he emulsion which has now commenced to break passes upward along the lower surfaces of troughs I3 and then upward along the lower surfaces of troughs I4, I5, I6, I1, I8 and I9 in succession. By the time it reaches the top of the system the water has been practically completely separated and the demulsified oil forms a layer at the top of the treating tank. This layer overflows through enlarged pipe 4I and then out of the system through pipes 32 and 43 -to storage or other facilities.

As shown, the troughs may suitably be supported by means of columns 44. Treating tank I I and all its internal equipment except the pipes, fittings, etc. are preferably made of Wood and the various elements may suitably be put together with copper nails, brass screws, etc. This gives an inexpensive, corrosion proof construction. It is however, particularly important that the troughs or baffles, and still more particularly their under surfaces, should be of wood.

Also as shown in the drawings, tank II may be provided with clean out boxes 45.

In order to prevent the films or globules of the emulsion from spreading laterally beyond the edges of the troughs and in vorder to keep the emulsion distributed across the troughs, the latter are provided with drop sides 46 and rails 41.

Devices similar to saddles 31 can also be used on the lower parts of the other troughs if better redistribution is desired.

I have found that in my new process and apparatus the use of wood batiles has a very real, important and outstanding advantage over the use of bafiles made of other materials, for instance metals. I do not know of any completely satisfactory explanation for this but the fact of the superiority of the wood bailies is very weil established and these wood baiiled treating tanks have come into wide spread use in the industry. It appears that the normally rough surface of the unfinished or semi-finished wood usually used tends to enhance the nlm rupturing effect of the rolling particles by subjecting them to an uneven surface and by puncturing them at intervals due to surface irregularities.

I have described my invention particularly in connection with a certain form of apparatus. This form of apparatus has proven highly important and highly successful and it forms a major portion of my invention.-

While I have described my invention in connection with certain embodiments and in connection with certain theories which may explain its success, it is to be understood that these embodiments and these theories are by way of illustration rather than by way of limitation and that I do not mean to be bound thereby but only to the broadest, valid interpretation of the appended claims in which `I will denne my invention.

I claim: l

1. An apparatus for treating a petroleum emulsion comprising a tank and a plurality of wooden bafiles in said tank, said wooden baiiles being disposed at small angles to the horizontal in zig-zag relationship to each other, means for introducing a body of water into said tank to cover said bailles, and means for introducing said petroleum emulsion into said tank below the lowest of said batlies, whereby said emulsion can be broken by passing it upward through said body of water along the lower surfaces of said bailles in succession.

2. An apparatus according to claim 1 which includes means for withdrawing the de-emulsifled petroleum from said tank at a level above the uppermost of said wooden bailies, and means for maintaining a substantially constant water level in said tank, said water level being located slightly below the level at which said de-emulsiiied petroleum is withdrawn.

3. An apparatus for treating a petroleum emulsion which contains an oil phase, an aqueous phase and gas, which apparatus comprises a gas separator, means for introducing an emulsion into said separator, a treating tank, a gas lineI leading from said separator and connecting with the top of said treating tank, an oil line leading from said separator to the bottom of said treating tank, a plurality of wooden baiiies in said tank,.said wooden baiiles being disposed at small angles to the horizontal in zig-zag relationship to each other, means for introducing a body of water into said tank to cover said baflies, and means for introducing said petroleum emulsion into said tank below the lowest of said baflies, whereby said emulsion can be broken by passing it upward through said body of water along the lower surfaces of said baiiies in succession.

4. An apparatus according to claim 3 which includes a distributor for distributing said emulsion laterally across said baiiles.

5. An apparatus according to claim 3 in which said baffles are equipped with drop sides to prevent the lateral spreading of said'emulsion.

6. An apparatus for treating petroleum emulsions Vcomprising a tank and a plurality of inverted wooden troughs in said tank, said inverted wooden troughs being disposed at small angles to the horizontal in overlapping zig-zag relationship to each other, means for introducing a body of water into said tank to cover said troughs and means for introducing said petroleum emulsion into said tank below the lowest oi' said troughs, whereby said emulsion can be broken by passing it upward through said body of water along the under sides of said troughs in succession. i

'7. An apparatus according to 4claim 6 in which said troughs are arranged in pairs on the two sides of a central column within said tank.

8. An apparatus according to claim 8 wherein said troughs are equipped with drop ends :to prevent short circulting of the emulsion.

9. An apparatus according to claim 8 in which said troughs carry a plurality of longitudinal rails on their undersurfaces in order to maintain the distribution of the emulsion.

i0. An ppratus according to claim 6 which includes a saw-toothed distributor located between said means for introducing said petroleum emulsion 'andthe-lowest of said troughs.