US2934087A - Tank bleeder - Google Patents

Description

April 26, 1960 A. E. CROW 2,934,087

TANK BLEEDER Original Filed May 19, 1952 mvsmon Anos E. C'eow ATTORNEY United States Patent TANK BLEEDER Amos E. Crow, Long Beach, Calif.

Original application May 19, 1952, Seriai No. 288,685, now Patent No. 2,732,071, dated January 24, 1956. Divided and this application January 12, 1956, Serial No. 558,800

3 Claims. (Cl. 137-590) The present invention relates generally to the storage of liquids within tanks, and more particularly to a novel tank bleeder for use with liquid storage tanks.

This application is a division of my application Serial No. 288,685 entitled Tank Bleeder, filed in the Patent Oflice on May 19, 1952, which issued on January 24, 1956, as Patent No. 2, 732,071.

Liquid storage tanks are widely used throughout the world today. In many instances it is necessary to store a plurality of liquids having difierent specific gravities in a single storage tank whereby such liquids will assume separate horizontal stratums. A common example occurs where oil or other hydro-carbon is stored in a tank together with water, which water may have entered the tank with the oil or perhaps later entered the tank by means of leakage or condensation. Inasmuch as such water will have a greater specific gravity than the oil it will settle to the lower part of the tank in the form of a. strata. Thereafter, at such time as it becomes desirable to remove the oil from the tank this strata of water must be bled oil, whereafter substantially uncontaminated oil will remain for withdrawal.

The means heretofore proposed for bleeding off such water has generally comprised a selectively-openable outlet of a comparatively small diameter located near the bottom of the tank. Occasionally, a horizontal pipe of the same diameter as such outlet may be inserted therethrough so as to draw water from a position spaced inwardly from the side of the tank wherein the outlet is formed. With either of these arrangements, unsatisfactory results are obtained inasmuch as considerable turbulence is developed by water entering the small diameter outlet or pipe. Such turbulence eflects an intermixing of the oil disposed above the water with the water being bl d from the tank, whereby a certain amount of this intermixed oil is bled ofi together with the water. in this manner a considerable amount of oil may be lost. However, it is true that such oil which is bled off with the water may be later recovered by a resettling process or the like, but such process involves an appreciable amount of time and trouble and hence is to be avoided.

It is possible to avoid such turbulence and its consequent intermixing of oil with the water being bled oil by permitting the water to bleed ofi at a very slow rate. The slow Withdrawal rate, however, is generally objectionable, primarily because an operator must stand by during the bleeding operation in order that he may close the outlet valve the moment the oil begins to drain from the tank. Accordingly, it is important that the bleeding oil be accomplished as quickly as possible whereby the operator may leave the tank and attend to his other duties. A slow withdrawal rate is also objectionable inasmuch as it prevents the immediate re-use of the storage tank with a new body of oil.

It is a major object of the present invention to provide a tank bleeder for storage tanks which permits a tank to be bled in a minimum amount of time and with a minimum amount of turbulence.

It is a further object of the present invention to provide a tank bleeder for storage tanks which is simple of design and rugged of construction, whereby it may have a long and trouble-free service life.

It is another object of the present invention to provide a tank bleeder for storage tanks which maybe made from readily obtainable materials and by simple manufactoring processes whereby it may be sold at a low price.

An additional object of the present invention is to provide a tank bleeder for storage tanks which has a novel arrangement for returning any liquid of a lower specific gravity than that being bled oil which inadvertently enters the bleeder to return to the main body of such lighter liquid.

Other objects and advantages of the present invention will become apparent from the following detailed description thereof when taken in conjunction with the appended drawings wherein:

The single figure is a side elevational view of the invention.

Referring to the drawing, the lower portion of a storage tank designated generally by the numeral 10 is shown that includes a bottom 12 in which an opening 14 is formed through which a liquid outlet pipe 26a extends upwardly. An oil and water mixture when discharged into tank 10 will gradually separate into two strata, the lower strata being water, and the upper strata oil. The present invention permits the water to be discharged from drain line 25a without any appreciable quantity of oil being discharged therewith as will be hereinafter explained in detail.

The invention 14a includes a circular metal base 16 having a central opening 18 formed therein through which drain line 26a extends upwardly, with the drain line being welded or otherwise aflixed to the portion of the base adjacent opening 18. The base rests on the bottom 12.

A number of circumferentially spaced first stud bolts 30 project upwardly from the upper peripheral edge of base 16. Also a number of circumferentially spaced stud bolts 32 of greater height than bolts 30 extend upwardly from base 16. Bolts 32 are relatively close to the .upwardly projecting end portion of liquid outlet pipe 265:.

Stud bolts 30 have tubular spacers 34 disposed thereon, the lower ends of which rest on the upper surface of base 16. Spacers 34 terminate substantial distances below the upper ends of bolts 39. Likewise, bolts 32 have tubular spacers 38 mounted thereon that rest on base 16 and terminate substantial distances below the upper ends of the bolts.

A frusto-conical turbulence shield 22a is provided that includes a ring-shaped flange 40 in which a number of circumferentially spaced bores 42 are formed through which the upper end portions of bolts 30 extend, with the flange being supported on the upper ends of spacers 34. The upper end portions of bolts 30 are threadedly engaged by nuts 44 to removably support the flange in a fixed position relative to base 16. A frusto-conical side wall 48 extends upwardly and inwardly from the inner peripheral edge of flange 40 and terminates in a first flat circular plate 50. A number of circumferentially spaced bores 52 are formed in plate through which the upper ends of bolts 32 extend. Side wall 48 has a number of apertures 54 formed therein, the purpose of which will be explained hereinafter.

A frusto-conical sheet metal collector 20a includes an upwardly and inwardly tapering side wall 56 that has an upwardly and outwardly tapered lip 58 extending around the lower peripheral edge portion thereof. Side Wall 56 terminates in a second circular plate 60 that has a number of circumferentially spaced-bores 64 formed therein through which the upper ends of bolts 32 extend. Plate 60 rests on the. upper eudsoi spacers 2,8. The upper sur-v cated by'the arrows. inthe drawing, Thereafter,

water will by gravity flow out of the tank through outlet pipe 26a. During the bleeding off of the water there w be t e t any tu i le s e cre te by the en ryo th a r n o t e co lecto -29- Tlt s esnltsimm the streamlining nact ci a ifito i ed ua nj he' a s n of the col ec o l the e n s me t b en -s ould o ur w er, her by a ma l an i y of; Oil s ul be drawn towards the large end of the oolleotor, the mai p t on of s h o l i l Pa pwardly int t annular space separating the inside of the turbulence shield 22:: and the exterior of the collector 20 2. From here the oil is free to pass through a plurality of apertures '54 formed about the upper portion of the turbulence shield .22. Inasmuch as the oil will'be lighter than the water, such oil as may pass through these apertures is and ur ulen e h el that dati g a lu a i y t openin s free to return upwardly to the main body of oil (not 7 shown).

Although there have been described what is at present considered to be the preferred forms of tank'bleeders embodying the present invention, it will be apparent to those skilled in the art that various modifications and changes may be made thereto without departing from the spirit of the invention or the scope of the appended claims.

I claim:

l. A tank bleederfor usein separating and drawingoif two layers of liquids differing in specific gravity from a tank due to the hydraulic head to which the lowermost layer is subjected, including:, an outlet pipe having a generally vertical open-ended portion that extends up.- wardly'from the bottom-part of said tank;;a frusto-conical turbulence shield, the central portion of which is positionedabove the upper extremity of said pipe and ms posed in a substantially horizontal plane, said shield having a continuous side wi hin which a plurality of apertures are formed; a horizontally disposed plate proecting outwardly from said vertical portion of'saicl pipe, sald plate extending beneathsaid turbulence shield and being vertically spaced therefrom; a plurality'of circumy and hold said plate and shield in said spaced relationship,

with the total area of said openings being such that fluid can flow therethrough without appreciable turbulence at the maximum rate said fluid can be discharged from said outlet pipe when said liquid tobe separated is subjected to the maximum hydraulie headpossible in said tank; a frusto-conical collector situated within, said turbulence shield, with the central portion of said collector being positioned above the upper extremity of said outlet pipe, said collector being fo-rmed with a continuous side wall disposed at a lesser angle tothe vertical than that or the side wall of said shield to define an annulus-shaped space therebetween with the lower horizontal edge of said collector terminating, inte'rmediately between the lower extremity of said shield and the upper surface of said base plate; and means for holding said collector and turbulence shield infixed relationship to permit separation of said iqu alter en n aid peni into, a fi t mo n stream flowing into said annulus-shaped SPE SE, and a second more rapidly moving stream flowing upwardly inside said collector to discharge into said pipe with the relative rate of flow of said streams being determined by thetotal area of saidapertures and the area of said openings, which area ratio is such that portions of said upper liquid layer inadvertently mixed with said lower liquid layer as it enters said bleeder will be directed, due to its natural tendency to rise into said first stream and continue said rise as said first stream flows through said apertures to return to the main body of said upper layer.

2. A tank bleeder as defined in claim 1 wherein said collector and turbulence shield are formed with flat central portions that abut against one another.

3.; A tank bleeder as defined in claim 1 wherein said holding means include a plurality of circumferentiallY 548,215 Montgomery Oct. 22, 1895 571,278 McCaWley l Nov. 10, 1896 833,150 Attenhofer Oct. 16, 1906 1,054,004 7 La Croix Feb. 25, 1913 1,716,544 Felted June 11, 1929 1,945,824 Saxe Feb. 6, 1934

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