US3096902A

US3096902A - Storage installation

Info

Publication number: US3096902A
Application number: US96813A
Authority: US
Inventors: Carl E Schroeder
Original assignee: Continental Oil Co
Current assignee: ConocoPhillips Co
Priority date: 1961-03-20
Filing date: 1961-03-20
Publication date: 1963-07-09
Anticipated expiration: 1980-07-09
Also published as: BE629010A; GB938520A; NL275984A

Abstract

938,520. Storing liquefied gases. CONTINENTAL OIL CO. March 7, 1962 [March 20, 1961], No. 8818/62. Class 8(2). [Also in Group XXIX] A reservoir for low temperature liquid gas comprises a container 21 suspended within a depression 17 in the ground above its bottom press means 16 which extend between supports 11 secured on at least two sides of the depression. The container 21 is attached to the crossextending I beams 16 by cables or rods with spring hangers 20 which may be omitted at positions near the centre of the tank which are not greatly affected by expansion. The depression 17 is lined with asphalt, plastic or other impervious material and the space 22 between it and the container 21 is filled with insulating material, loose or in bags. A cover 24 of sheet metal, plastic or other material extends over the beams 16 and its edges dip into a peripheral trough 13 which forms a water-seal. The gas mentioned is meltrane.

Description

July 9, 1963 c. E. SCHROEDER STORAGE INSTALLATION Filed March 20 link ATTORNEY United States Patent 3,096,902 STORAGE INSTALLATION Carl E. Schroeder, Ponca City, Okla, assignor to Continental Oil Company, Ponea City, Okla., a corporation of Delaware Filed Mar. 20, 1961, Ser. No. 96,813 12 Claims. c1. 220 1s This invention relates generally to a storage installation and more particularly to a suspended underground storage tank which may be utilized to contain low temperature liquids.

In large scale refinery and other manufacturing operations it is often necessary to store large quantities of liquids either temporarily or for extended periods of time. Heretofore, relatively large above-ground tanks have been utilized for this purpose. However, such tanks have not been found to be satisfactory for all conditions which may be encountered; and consequently, improvements in storage facilities have long been sought. In the usual above-ground storage installation it is often necessary to do extensive earth work to prepare the ground prior to the erection of the storage tanks. Moreover, relatively elaborate fundations are necessary, as are extensive dikes which must encompass a substantially greater area than is covered by the tank itself. In certain areas of extremely hard, irregular soil, the normal problems attendant to preparation of the area for the storage tanks are greatly magnified and in some instances may jeopardize the economic feasibility of the whole project.

With the advent of the use of large quantities of low temperature liquids, the problems arising from aboveground installation have increased. Due to the nature of these liquids, it is necessary that heat loss be maintained at a minimum; and in order to minimize this loss in the surface storage installations, various schemes have been tried. Among these are the securing of insulating ma terials around the exterior of the tanks and the use of double-walled tanks. In either case, the problems attendant to the erection and maintenance of the heat barriers have proved to be formidable.

The present invention contemplates a novel storage installation which can be erected quickly and economically and which is not subject to many of the problems brought about by surface storage. This installation comprises one or more foundation members disposed along sides of a depression in the earth. Disposed between each pair of foundation members is a support means to which flexible suspension means are connected in a position substantially over the depression. Secured to the suspension means is a container into which a material can be placed. Outside the container and within the walls of the depression is provided a vapor barrier as well as a quantity of insulating material.

An important object of this invention is to facilitate the storage of materials with minimum heat loss therefrom.

Another object of this invention is to provide a liquid storage installation which does not necessitate the use of extensive dikes.

A further object of this invention is to provide a storage installation which may be quickly and economically installed under adverse terrain conditions.

Another object of this invention is to provide a storage installation wherein thermal stresses are minimized.

Yet another object of this invention is to provide a storage installation which is less susceptible to puncture or other injury.

Other objects and advantages of the invention will be evident from the following detailed description when read in conjunction with the accompanying drawings which illustrate one embodiment of my invention.

In the drawings:

FIGURE 1 is a perspective view, partially cut away, of an underground storage installation embodying this invention. Insulation used therein has been omitted for clarity.

FIGURE 2 is an enlarged cross sectional view taken on line 22 of FIGURE 1 showing in greater detail a vapor sealing arrangement as well as insulation used therein.

Referring now to the drawings and in particular to FIGURE 1, there is shown along the surface of the earth a plurality of paired foundation members 11 which can be partially buried, as indicated at 12 in FIGURE 2. While the foundation members are shown in the drawing as being of a particular shape, it is to be understood that other forms may be used. For example, piling might be substituted for the disclosed structure, or a single pair of substantial parallel horizontal foundations might be used in the place of the plurality of pairs shown. Formed within the body of each of the foundation members 11 is a U-shaped notch 13 in which is shown a continuous elongate trough 14 which can be made of steel, plastic, or other impervious materials. As best shown in FIGURE 1, liquid, such as water, is placed in trough '14 for a purpose hereinafter described. Terminating in proximity to trough 14 are a plurality of support means such as I-beams 16 which are placed on or secured to the pairs of opposed foundation members 11. The central portion of each of the beams is suspended over a pit or depression 17 formed in the earth and has attached thereto a plurality of clevises 15. To these clevises are attached spring hangers 20 from which depend suspension means 18 which can be either flexible cable or rigid bar. It is to be understood that while these suspension means are shown to be of equal length in the drawings, it is contemplated that they can be of unequal length, depending upon the relative elevation of foundation members 11. Further, the spring hangers 20 may be omitted near the center of the tank if desired, or may be omitted entirely when the length of the installation is such that thermal contraction is relatively small.

A clevis 19 is attached at the lower end of each of the suspension means 18 and has secured thereto a container 21 which is suspended thereby above the bottom of pit 17. While a reactangular tank having a. square cross section is shown in the drawings, many other types of tanks may be usedfor this purpose, such as a cylindrical tank, or should the occasion warrant, a semicircular tank, to mention a few. Moreover, bracing or other stiffening members may be added to the tank as the circumstances demand. Such bracing has been omitted in the drawings for clarity, and inasmuch as particular bracing or stiffening arrangements will vary depending upon the size, shape and material of the tank and can be added by anyone skilled in the art. In addition, if it is desired, cribbing may be added beneath the tank without departing from. the spirit of this invention.

Exterior of container 21 is provided a quantity .of in sulating material 22 which may be made of perlite, either loose or in bags, mineral wool, glass Wool or any other insulating materials which are well known and which will be obvious to one skilled in the art. Contacting the insulating material can be a liquid-vapor barrier 23 which is applied to the sides of pit or depression 17. The barrier may be formed from one or more of many wellknown materials such as asphalt, gunite, plastic, or a variety of other materials which are well known in the art. Secured above pit 17 and resting upon I-beams 16, is a substantially impervious sheet or cover 24 having flanges 26 formed on all four edges thereof. This cover can be made of any impervious material such as steel, aluminum or other sheet metal, plastic, rubberized canvas or other materials. Flanges 26 extend into the liquid to store only 60,750 cubic feet.

contained in trough 14 which is disposed on all four sides of pit 17. By this arrangement, is it possible to maintain a vapor-tight seal completely surrounding pit 17 and thus prevent vapor losses from container 21. Of course, other edge sealing methods may be utilized without departing from the scope of this invention. For instance, the flanges 26 could be fastened to foundation members 11 with the portion of the flanges between the members being buried. Alternately, a member could be provided between members 11 to which the flanges 26 could be fastened.

In use, a quantity of material, for instance, low temperature LPG is placed in container 21, after which cover 24 is placed thereon with flanges 26 extending into trough 14. Under these conditions, heat loss will, due to the presence of insulating materials 22, be maintained at a minimum, as will vapor losses due to the sealing arrangement made possible by flanges 26 and trough 14. Should rupture of the container 21 occur, the lack of extensive diking will not be a factor inasmuch as the liquid within the container will flow into pit or depression 17 without attendant loss or adulteration of the surrounding countryside. Since exte-nsive dike work is not necessary, it is possible by this arrangement to better utilize a given surface area. Simple computations indicate that it is possible when using the present installation to store 486,000 cubic feet of material; where before, using conventional surface storage, it was possible Moreover, inasmuch as container 21 is suspended, any thermal expansion or contraction therein will result only in the slight lowering or elevating of the bottom of container 21 and slight 1 movement of the ends of container-21 which is allowed by clevises 15 and 19 and will not induce thermal stress therein. 1

While particular embodiments of the invention have been described, it will be understood, of course, that the invention is not limited thereto, since many modifications may be made; and it is therefore contemplated to cover by the appended claims any such modifications as fall within the true spirit and scope of the invention.

The invention having thus been described, what is claimed and desired to be secured by Letters Patent is:

1. A reservoir comprising a depression in the ground, support means secured on at least two sides of said depression and extending thereacross, a plurality of cables connected 'to said support means and a container secured to said cables and suspended thereby within said depression above the bottom thereof.

2. A reservoir comprising a depression in the ground, a plurality of beams secured on opposite sides of said depression and extending thereacross elongate, suspension means depending from each of said beams toward the bottom of said depression, a clevis at the lower end of said means, and a container secured to said suspension means by said clevises and suspended thereby Within said depression above the bottom thereof.

v3:. A reservoir comprising a pit in the ground, a plurality of beams secured on opposite sides of said pit and extending thereacross, a plurality of elongated downwardly extending suspension members secured to each of said beams at the central portion thereof a. clevis at each end of said members, and a container secured to said suspension members by said olevises and suspended thereby within said pit above the bottom thereof.

4. A reservoir comprising a pit in the ground, support means secured on at least two sides of said pit and extending thereacross, suspension means connected to said support means, a container secured to said suspension means and suspended thereby within said pit above the bottom thereof, a substantially impervious sheet disposed above said container, and means for sealing the edges of said sheet to prevent escape of vapor from said pit.

5. A reservoir comprising a pit formed in the ground, a plurality of beams secured on opposite sides of said pit and extending thereacross, a plurality of elongated, downwardly extending suspension members secured to each of said beams on the central portion thereof, a container secured to said suspension members and suspended thereby within said pit above the bottom thereof, a substantially impervious sheet disposed above said beams, and means for sealing the edges of said sheet to prevent escape of vapor from said pit.

6. A reservoir comprising a depression in the ground, support means secured on at least two sides of said depression and extending thereacross, suspension mean connected to said support means said suspension means including a clevis at the points of connection with said support means and a spring secured to each clevis, a container secured to said suspension means, a liquid barrier between said container and the walls of said depression, and insulating material disposed between said barrier and said container.

7. The structure recited in claim 6 wherein said support means include a plurality of beams.

8. The structure recited in claim 7 wherein said suspension means includes a cable connected to each of said springs.

9. The structure recited in claim 8 wherein a substantially impervious sheet is disposed above said support means and means are provided for sealing the edges of said sheet to'prevent escape of vapor from said depression.

10. The stnucture recited in claim 6 wherein a plurality of foundation members are provided beneath a portion of said support means.

11. The structure recited in claim 10 wherein a substantially impervious sheet is disposed above said support means.

12. A reservoir comprising a depression in the ground, a plurality of beams secured on at least two sides of said depression and extending thereacross, a plurality of cables connected to said beams, a container secured to said oables, a liquid barrier between said container and the walls of said depression, insulating material disposed between said barrier and said container, a substantially impervious sheet disposed above said support means, and means for sealing the edges of said sheet to prevent the escape of vapor from said depression.

References Cited in the file of this patent UNITED STATES PATENTS

Claims

1. A RESERVOIR COMPRISING A DEPRESSION IN THE GROUND, SUPPORT MEANS SECURED ON AT LEAST TWO SIDES OF SAID DEPRESSION AND EXTENDING THEREACROSS, A PLURALITY OF CABLES CONNECTED TO SAID SUPPORT MEANS AND A CONTAINER SECURED