US2608303A - Apparatus for liquid separation - Google Patents

Description

Aug. 26, 1952 R. G. FORD 2,608,303

APPARATUS FOR LIQUID SEPARATIQN Filed March 4, 1950 I 2 SHEETSFSHEET 1 INVENTOR Rzzyncoizd G.FOId

Aug. 26, 1952 R. e. FORD 2,608,303

APPARATUS FOR LIQUID SEPARATION Filed March 4, 1950 2 SHEETS-SHEET 2 INVENTOR Raynzbzzd 6.1 61.1

qw m8) ATTORNEY Patented Aug. 26, 1952.

UNITED STATES PATENT OFFICE APPARATUS FOR LIQUID SEPARATION Raymond G. Ford, Marshall, Tex.

Application March 4, 1950, Serial No. 147,729

1 Claim. 1

This invention relates broadly to the art of separating liquids, and in its more specific aspects it relates to a method and apparatus for raising liquids of different densities from storage or the like tanks into a separator column for the separation thereof, and the nature and. objects of the invention will bereadily recognized and understood by those skilled in the arts to which it relates in the light of the following explanation and detailed description of the accompanying drawings illustrating what I at present believe to be the preferred embodiments and mechanical expressions of my invention from among various other forms, arrangements, combinations and constructions, of which the invention is capable Within the spirit and scope thereof.

Liquid petroleum products such as light oils or gasoline are usually stored in tanks at the storage depot or at gas stations where the oil is sold to the consumer, and oils of this character are also transported in oil tanks by rail or truck. It is with the cleaning of such tanks and the raising of the oil from such tanks for the separation of water therefrom with which this invention is particularly concerned. While I have set forth several examples of tankage practices within the industry it is to be understood that this invention is adaptable for use with any type of container or tank in which light oils may be kept, either for transportation, storage or for any other purpose.

When petroleum products are refined it is a well known fact that all of the water is not removed therefrom, and when such products are transported or stored moisture from condensation is also absorbed thereby. When light oils, such as gasoline is stored in underground tanks at the usual gas servicing station or the like the filler caps or openings are often flush with the surface of the concrete or the like ground surface so that when such pavement or surface is flushed with water from a hose in cleaning, or when it rains, water is apt to and very often does gain entry into the gasoline stored in the tank through the filler cap and pipe. It will therefore be obvious that most of the light petroleum products, such as gasoline, often contains a certain amount of water.

Impurities other than water often find their way into gasoline and other light petroleum products. For instance sand and the like is not always entirely removed from oils in the refining process, and the tanks in which the oils are stored or transported become dirty and contain rust and sludge which may be carried therefrom with the oil as it is drawn from the tank.

The presence of water and other impurities in gasoline and other light petroleum products is objectionable for a variety of reasons. It will be evident that water, for instance, may cause the pump which is used to draw the oil from the tank to freeze in cold weather and therefore to become inoperable. Sand, grit and other gritty substances which may be contained in the oils may also have deleterious effects on the pumping equipment. It will be evident that oil which contains water or other impurities will of course not produce the best results when used as a fuel for internal combustion, diesel and the like engines. It is therefore the primary purpose of my invention to provide a method and apparatus which may be used by the dispenser of light petroleum oils, or by anyone employing tanks containing such oils, whereby the impurities may be separated from the oils within the tank. A further fundamental purpose of my invention is to provide a simple and inexpensive apparatus for accomplishing this purifying operation.

Light petroleum oils and water are, of course, immiscible, and the water being the heavier will sink to the bottom, as will other impure particles which may be contained within the tank of oil. Thus, in a tank containing oil, and the ever present proportion of undesirable water, the latter will sink to the bottom, and in view of this I have devised my apparatus so that it first draws off the liquids and particles from the lower portion of the tank for separation in a separator column which forms a part of my apparatus. Therefore in the practice of my method of separation it is not essential to draw off or disturb all of the contained liquid in order to cause a complete separation of the water from the liquid. It will be appreciated that I thereby save time and greatly expedite the separation operation.

The apparatus which I have devised for separating Water and other impurities from light petroleum oils, consists generally of a separator cylinder or column into which the liquids from the bottom of the tank are drawn by vacuum means. The vacuum within the cylinder may be produced by a novel jet arrangement forming a part of the apparatus, the jet which I have devised is particularly adapted to utilize compressed air which is always available at service stations and at most depots or the like where oil storage tanks are used; In practicing the separation process with my apparatus it is only 3 necessary to fill the separator cylinder with liquid from the oil tank, and I have provided. means of a novel nature for informing the operator of the apparatus when the separator cylinder is filled with liquid drawn from the tank. In draining the liquids from the bottom of the cylinder it will be apparent to the operator when water ceases flowing therefrom and oil starts. When this happens it indicates that all of the water has been separated from the oil in the tank and that the rest or" the liquid within the cylinder is oil. Means are provided on the cylinder for actuation by the operator to drain the remaining oil in the cylinder back into the tank, and not for waste discharge from the system. The number of times the separator cylinder must be charged and drained before all of the water and other impurities are removed from the tank is dependent upon the quantity of water and other impurities which may be contained in any particular tank- One of the important features of my method resides in the withdrawin of the liquids from the bottom of the storage tank into a cylinder by means of suction created by a vacuum within the cylinder. Since the impurities such as water, rust andthe like contained in the oil have settled into the bottom of the tank it will be recognized tom until substantially all have been withdrawn into the cylinder.

In prior methods of separating water and other impurities from oils in tanks with which I am familiar, the suction line from pumps of, various types are inserted into the tanks, priming being necessary, together with a foot valve at the base of the pipe for maintaining the primed condition of the, pump. Now it willbe evident that in the operation of suchpumps the foot valve will create a surge in the contained liquids by opening and closing thereby disturbing the contents of the tank causing the water and other impurities to mixin such a manner that the water and other impurities will be held in suspension in the oil so that it is impossiblev to completely and theroughly separate the liquids and particles without withdrawing a major portion of the liquids from the tank.

The method and apparatus which I have devised creates no agitation or disturbance of the tank contained liquids, and since withdrawal is from the bottom of the tank the withdrawn liquid will be mainly water and other impurities and until the greater part of the water is withdrawn practically no oil will be removed from the tank. When the amount of water in the tank is substantially reduced relative to the oil, some oil will be withdrawn from the tank with the water.

It is highly advantageous in the removal of water and sludge from oil storage and the like tanks to accomplish this without withdrawing all, or a major portion of the contained oil.' In many cleaning systems now known. and in use the pumps which areusedcause considerable agitation of the contained liquids and therefore withdraw from the tank a greater volume of oil than is necessary for the removal of the water and other impurities. The apparatus of this invention produces practically no agitation within the tankand since the liquid is withdrawn from the bottom of the tank where the heavier water and other impurities are it will be appreciated that a minimum amount of oils is withdrawn. Thus, a considerable saving'in time and efiiciency of operation results.

This invention involves an apparatus having substantially no moving parts to get out of order or to require replacement and is therefore exceedingly economical to operate. It is also constructed of relatively simple parts so that it is inexpensive to produce and may be assembled with facility. Its operation does not require the attention of a skilled operator for it may be opae ated by anyone who would normally be hired by a service station or by any unskilled workman. No machinery, other than the conventional air compressor is required in its operation.

With the foregoing general objects, features and results in view, as well as certain others which. will be apparent from the following explanation, the invention consists in certain novel features in design, construction, mounting and combination of, elements, as will .be more fully and. particularly referred to and specified hereinafter.

In the accompanyingdrawings:

Fig. 1, is a view in perspective of an underground oil storage tank with the apparatus of this invention, in operative position for withdrawing the necessary proportion of the contained liquids in order t separatethe water and other impurities therefrom.

Fig. 2 is a horizontal sectional view of the separater column orcylinder and jet structure of my liquidxpumping apparatus.

Fig. 3, is a View taken on line 3-3 of. Fig. 2.

Fig. 4 is a view in vertical section of my ap paratus with, the separator cylinder filled with liquid. from the storage tank, the denser water being in the. lower part of the cylinder the oil in the upper partv thereof.

Fig. 5 is a View similar to Fig. 4 after the separation and. draining has partially taken place in the separator cylinder.

The apparatus of this invention by which the liquids contained in a storage or the like tank are withdrawn into a cylinder or column for separating the water and other impurities from light petroleum, oils and the like, consists of a sepai'ator cylinder or column which I have designated by the numeral The cylinder is preferahiy of constant diameter throughout its length and is closed at the upper end thereof by an imperforate-plate or-the like element 3. At its op posite 01' lower end the cylinder is provided with a further plate 5. of circular shape conforming in diameter to that-of the cylinder, and. the plate 5 is drilled concentrically, formin a central opening- 1 therethrough; The opening "I may be in diameter. The separator cylinder or column I may be constructed of metal, plastic, or other suitable material, as may the end plates 3 and 5.. The end plates are permanently associated with theends of the cylinder in a leakprooi manner, as by welding or in. any other desirable way. As one example, of a size of cylinder whichl'have found toibe efficient'in a typical installation the length thereof may be approximately 18" and the, inside diameter 1 the capacity of the tank being" approximately one pint of liquid.

An opening 9is formed inthe'wall of the cylinder adjacent to but downwardly spaced from the top of the cylinder, andafurther opening II is formed, in the; Wall. of the cylinder at a point diametrically opposite to the aperture 9. The opening II is of slightly greater diameter than the opening 9 in the cylinder. I have found that the opening 9 may be substantially A" and the opening 11%" in a typical installation. It is to be understood that these sizes may of course be varied to suit the particular demands'of different installations. I have also found that in the usual installation an efficient operation results when the openings 9 and II are spaced approximately 1" from the top of the cylinder.

I provide a further hole or opening I3 in the wall of the cylinder at substantially the bottom thereof, This opening I3 is of substantially the same dimensions as the opening ,II adjacent the top of the cylinder and is in the same vertical plane as the opening I I.

Extending through the openings 9 and l I adjacent the upper end of the cylinder and through the cylinder itself is an air tube which I have designated generally by the numeral I5 and which is preferably though not necessarily formed of steel tubing. The tube I5, as explained, extends through the opening 9 in the cylinder, and having an outside diameter of substantially fits snugly in this opening. The air tube is supported and permanently fixed in the opening by welding or in any other suitable manner. The tube I5 is so positioned relatively to the cylinder that a portion thereof extends radially from the cylinder and the end of this radially extending portion I! may have an enlargement or the like I9 thereon for a purpose to be hereinafter described. The air tube is of a length so that it extends through the cylinder and through the opposite opening I I and radially beyond the cylinder as at 2|. The air tube being mounted and supported in opening 9 which is exactly diametrically opposite the large opening I I, will extend through said larger o ening concentrically thereto so that a free annular space is provided between the wall of the tube and the edges of the opening I I in the cylinder. It will be appreciated from consideration of the drawings that the air tube [5 extends through the cylinder I and radially outwardly therefrom in opposite directions. In a typical installation the air tube may be approximately 5 in length and the portion I1 thereof may be approximately /2" in length, while the extended portion 2I may be approximately 3%" in length. The end of the extending portion 2| is rounded down to form an air jet producing nozzle 23 having an air exhaust orifice 25 therein.

I fix by welding or the like a length of open ended tubing 2! in the orifice II. This tubing which I shall term the atomizer tube may be of approximately diameter so as to fit snugly within the opening I I. It will be recognized that the diameter of the atomizer tube should be substantially the same as the diameter of the opening I I. The atomizer tube 21 is preferably formed of metal and may be substantially 8" in length so that it extends beyond the end of the extending portion 2] of the tube l5. It Will be evident that the tube 21 surrounds the portion 2| of tube I5 and that the outer open end 28 of tube 21 forms an atomizer nozzle.

A radially extending nipple 29 is preferably permanently fixed within the opening I3 in the cylinder and a cutoii cook or other suitable control valve 3| is threaded or otherwise attached on the outer end of the nipple 29. A similar nipple 33 is preferably permanently fixed in the hole or opening I in the bottom of the cylinder and a shutoff cook or other suitable control valve 35 is threaded or otherwiseattached to the outerend of the nipple. It is to be understood that the diameters of the nipples 29 and 33 should be substantially the same as the diameters of the openings I3 and I- 'respectively. A bushing 31 is screwed into the lower end of the cutofi cock and a dip tube 39 is screwed into the bushing or the extended end of the cutoff cock. This dip tube will vary in length from 1' to 15", depending upon the position of the storage tank from which the liquid is to be drained for separation of thewater and other impurities from the oil. I

The majority of oil storage tanks are underground and therefore in Fig. 1 of the drawings I have illustrated my apparatus inoperative position relative to an underground tank II. Underground storage tanks of this character conventionally include an air vent 43, a filler pipe 45 and suction line 41 through which the liquid contents are drawn from the tank for use or sale, such pipes or lines extending to the surface. of the ground which I have indicated by the numeral 49.

In the operation of the apparatus to draw liquid from the tank 4| the dip tube 39 is inserted to the bottom of the tank through the filler pipe 45, the cock 35'Whi0h controls the inlet into the cylinder is opened and the cutoff cock 3I which is the drain cutoff is closed. j When these cocks are set as described the operator of the apparatus attaches a compressed air line 5| to the enlargement I9 on the extension, II of the air tube I5 and .air under pressure flows through the tube and exhausts therefrom through the orifice 25 in the opposite extension IZI of the air tube. This produces a jet action and creates a vacuum in the atomizer tube 21 Since the atomizer tube communicates through the opening II with the interior of the cylinder I a vacuum is created in the cylinder and the liquid from the bottom of the storage tank 44 will be drawn upwardly through dip tube 39, cutoff valve valve 35, nipple 33 and into the cylinder. Compressed air is permittedto flow through the air tube until the cylinder isfull of liquid, at which time the liquid will be drawn into tube 21; atomized and will start exhausting in spray form through the open end 28 of tube 21. When this occurs the operator will see the spray and will thereby know that the cylinder I is filled with liquid and the separation step should begin. Immediately upon exhaust of spray from the end 28 of tube 2! the operator will close cutoff cock 35 and disconnect the compressed air line from the air tube. If the capacity of the cylinder isless than the amount of water and other impurities contained in the tank the charge of liquid withdrawn into the cylinder will contain practically no oil due to the fact that the liquids in the tank are not disturbed, agitated or mixed up by the steady constant sucking action created by the vacuum. Hence, until a major portion of the water is withdrawn from the tank each filling of the cylinder will consist primarily of water and other impurities; however when most of the water has been withdrawn from the tank, some oil will then be withdrawn with the water and the separation within the cylinder will take place. The number of times the cylinder will have to be'filled will depend upon "the amount of water within the tank. It is to be understood that when; both oil and water are being withdrawn from the tankaseparating action begins as the Iiquid'sare sucked into the oil will ascend into: the cylinder at a more rapid rateithan the heavier water and other impurities; Since the densities of oil and water and other impurities are. difieren't', the waterand other impuritie being heavier, will immediately sink to the: bottomofQthe cylinder. Fig. 4' of the drawings indicates the condition of the sys-- tem just prior to th'e occurrence of the atomizing action, that is when the cylinder is substantially filled with liquid and just: prior to closing cock 35 and stopping the flow: of compressed air in the apparatus, and since both oil and Water are contained in" the cylinder it will be recognized that-the major portion: of-the'water in the tank has been withdrawn.

The cock 3| is now opened and the water is drained from the cylinder. Since cock 3 is "at the bottom of the cylinder it will, of course be clear that such: water and other impurities will drain throughnipple 29 and cock 3! before any oil is drained therefrom. The operator of the apparatus will watch the liquid being drained off and as soon as he sees oil-flowing from cook 3 I"he will know that all of the water has been separated from the oil in the cylinder, Whereupon cock 3-! will be closed and cook 35' opened sothat the: oil which is freed of water within the cylinder will flowback into the storage tank 41'. This charging and draining of thecylinder with liquid from the tank is continued until oil first flows from cock 3-! instead of water. When this occurs it will be apparent that the oil in the storage tank has been freed of all" water and other impurities.

Fig. 5 of the drawings illustrates the condition of the apparatus just as the oil is starting to flow through cock 3'! and-just before this cock closed and cook- 35 opened sothat oil will fiowfrom thecylinder back into thestorage tank 4 i The major portion of the oil within the storage tank will not" be disturbed by this separating operation, since the'dip tube is inserted into the tank so as'to extend to the bottom thereof where any Water will be, and the suction created by the-vacuum in the cylinder will not cause any agitation of the entire body of liquid contained within the tank.

It is to be distinctly'understood'that the various dimensions of" the parts of my apparatus which I- have set forth'herein are not to be construed as limiting my invention to these particular relative dimensions; instead they have been set forth merely as one example from among many which may be successfully used. Itwill be recognized. that my apparatus and method may be used toseparate water from lightpetroleum oils which are. containedin many difierent types of tanks, and not only those which are situated underground. While I have mentioned gasoline as one type of'liquid which may be stored and from which water may be separated, it will be apparent that I do notintendto limit this invention-to theseparation of water and'other impurities only from gasoline.

It will be appreciated that I have devised a method and apparatus-in which no priming is necessary, no labor required, as with a hand pump and the power for operation of the apparatus being compressed is always available at filling stations or-rthe like. No wrenches or other toolsare needed in the operation and association of 'the-apparatus with a tank, only pressure of air clutch as when airing up a tire. In the use 8; of my apparatus it will be clear that there is no waste whatsoever of the petroleum products, and the method is emcient and time saving and involves no maintenance costs and is economical to produce. The entire apparatus is of'small size requiring little space for storage.

I claim:

Apparatus for separating liquids of difierent densities contained within a tank including a separator cylinder, the major portion of the interior of which is free of obstruction, the cylinder being closed at its upper end and having a dip tube extending axially from its lower end and in communication with the interior of the separator cylinder, the dip tube adapted to extend from the separator cylinder into the tank and having a valve therein to control the flow of liquid to and from the separator cylinder and the tanlqthe separator cylinder having a radial- 1y extending outlet at the bottom thereof having a valve therein and emptying exteriorly of the cylinder and tank to control flow of' liquid therethrough from the cylinder, and means for creating a vacuum within the cylinder for drawing, the liquids from the tank into the. cylinder for separation therein by the settling of the heavier liquid to the bottom of the cylinder, said vacuum creating, means comprising, an air tube mounted in and extending through diametrically opposite openings in the wall of the cylinderv ad,- jacent the upper end thereof, the air tube being of such dimensions that the ends thereof extend radially in opposite directions from the-cylinder; one of said radially extending portionsof the air tube having a reduced nozzle forming end and the other of said radially extending portions adapted to receive-air under pressure for the flow thereof through the tube, and an atomizer tube of larger diameter. than. said air tube mounted in one of the openings in the wall of said cylinder and extending. radially therefrom and inposition surrounding and extending. radially be yond said first mentioned radially extendingporetion of the air tube, and said atomizer tube being in communication with the interior ofthe cylinder, whereby air flowing through said air tube and exhausting from the nozzle thereof into said atomizer tube will create a vacuum in the cylinder for drawing liquid from the tank into the cylinder forsettling therein, the heavier liquid being drawn from the cylinder through the radially extending outlet at the bottom thereof and the lighter liquid being drained back into the tank'frcm the'cylinder through the dip'tube.

' RAYMOND G. FORD.

nanearners orrnn The following references are of record in the file of this patent:

UNITED STATES PATENTS Numoer Name Date 41,158 Lansdell Jan. 5, 1864 266,204 Roeckner Oct. 17, 1882 457,917 Shaw Aug. 18, 1891 1,079,398 Coakley etal Nov. 25, 1913 1,343,471 Otterson June 15, 1920 1,691,060 Harrison Nov. 13, 1928 1,764,160 Finch June 17, 1930 FOREIGN PATENTS Number Country Date 320,239 Great Britain Oct. 10, 1929 3,476 Australia Aug. 25; 1926

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