DE1271733B - Erdbehaelter for storing liquefied gases at low temperatures and process for the production of such containers - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY GERMAN W7WW & PATENT OFFICE Int. Cl .:

F17c

EDITORIAL

German class: 17g-4

Number: 1271733

File number: P 12 71 733.8-13 (C 29131)

Filing date: February 11, 1963

Open date: 4th July 1968

The invention relates to the storage of liquefied gases at low temperatures in the ground.

It is an underground container for storing liquefied gases at low temperatures in one of the containers surrounding earth formation known, which contains a liquid that solidifies at low temperatures and remains solid when the container is filled with the liquefied gas to be stored. Such a Earth container has facilities for filling, emptying and venting the liquefied gas and is with a cover that insulates against heat.

By the term "liquefied gas" or "liquefied gas" is meant a liquid that at atmospheric Pressure boils at a temperature below ambient, such as liquefied Nitrogen, liquefied air, liquefied methane, liquefied natural gas, liquefied propane or liquefied oxygen.

It is known to ao liquefied natural gas and liquefied petroleum gases in underground cavities to store that either originated naturally or in liquid-impermeable rock are created. Similar known underground storage systems have been provided in salt formations. In general, however, are in the places where storage is intended Usable soil formations are not available.

It is also a funnel-shaped or pit-shaped earth container for liquefied gas storage known, the one Has concrete casing on which an insert rests, which is between two watertight or gas-tight, Layers formed from metal or asbestos laminates form a cavity that is filled with gravel is filled out. The outer waterproof layer is optionally protected against breakage by means of heating cables protected by the formation of ice from outside, caused by the low temperatures of the gas to be stored.

It is also the storage of liquefied gases in several separate containers in known from a pit dug out of the ground. The containers are designed as metal bottles, in which the liquefied gas can be stored under pressure, and are from the surrounding earth formation separated by a thermal insulation layer, so between the container contents and the No significant heat exchange takes place in the surrounding soil. This type of liquefied gas storage has proven to be too expensive and therefore uneconomical.

Another frozen earth container for storing liquefied gas under normal conditions is an earth container for storing liquefied gases
low temperatures and procedures for
Manufacture of such containers

Applicant:

Conch International Methane Limited,

Nassau (Bahama Islands)

Representative:

Dr.-Ing. F. Wuesthoff, Dipl.-Ing. G. Pulse
and Dr. E. v. Pechmann, patent attorneys,
8000 Munich 90, Schweigerstr. 2

Named as inventor:
Maurice Nachshen, London

Claimed priority:

Great Britain 12 February 1962 (5325)

A cooling system, which is surrounded by a layer of ice, is stretched over its opening and the opening of the container closes at the top and at the same time serves as a support for the ice cap and it at the Prevents melting, the surface of the ice layer is provided with protective insulation. That Cooling system is with an appropriate cooling system for absorption, compression and condensation of the vapors from the underground storage tank, which relaxes via a circuit through the cooling system and end in the container. This storage container also requires high investment and maintenance costs.

The problem of the economical storage of liquefied gas has therefore been attempted by that they are in containers in the form of excavated funnel-shaped pits or horizontal ones Carries out trenches with a relatively large surface, the walls of which may be frozen. The regarding the storage volume requires a relatively large surface area of the known storage container especially when the container is only moderately full, relatively large evaporation losses, as long as not a special, complex cover system to avoid evaporation losses on the large one Surface is provided. In addition, complex structural measures are necessary to the arising from gas evaporation, on the

809 568/211

large container cover acting pressure of the gases to melt frozen liquid, and finally to meet. Also, preventing air from entering the piping removes the liquid from the as well as maintaining a uniform pressure, pumping wells and these with one or more z. B. slightly above atmospheric pressure, prepares heat-insulating covers, With the known devices considerable difficulties can be 5 Die'Erdschächte by means of large mechanics. Even if you are being drilled by just a relative drill or with the help of Spemäßig low overpressure, e.g. B. 0.1 atü, zialzipern be dredged. If it would overall on the large cover area, which shows the rend of the drilling work that the soil is not known frozen liquefied natural gas storage is sufficient'stabil, you will use the shaft wise to act a considerable pressure. Stripping at least partially. However, this is then

The object of the invention is to create a soil not necessary if the shaft in clay, gravel, sand container for the storage of liquid gas, which is drilled in stone, lime or very dense sand, major disadvantages of the known liquid gas storage tank for the cooling and heating liquid do not adhere, the cover of which is proportionately used "Uoppelrohflinien, nism-moderately problem-free and its cold losses in 15 Another, compared to the aforementioned comparison to his. Storage volumes are low, modified advantageous method for driving and which allows simple and cheap manufacture. Manufacture of the above-mentioned earth containers consists in

For the earth container mentioned at the beginning, this is that after completion of the drilling work in. The Object according to the invention achieved in that the wells contained liquid of high specific Container in the form of a group of vertical 30 diameters through a liquid with low weight Erdschächten is formed, which replaces the freezing point in the earth's surface and the latter liquid small distances from each other and speed after freezing of the shaft walls through the optionally with each other at their top and circulation of a liquid in the pipelines lower ends are connected. . and after removing the pipelines from the

The as shafts surrounding the group of individual shafts pumps. The low-viscosity liquid and the freezing point in the earth between the shafts must have sufficient density, rich, which contains a liquid, which at low temperatures the shaft walls in front of the. Freezing of the earth temperature solidified and remains in the solidified state to support Reichs. Here, too, it becomes the when the container with the liquefied gas to be stored through the immediately surrounding soil through the shaft is filled, so forms the same as with the first and 30 circulating coolant in the pipelines last mentioned known storage containers immediately '' '. frozen. But you can also use the whisper bar instead the storage container walls. The single low freezing fluid that makes the difficult openings The earth shafts are replaced with relatively liquid, so pre-cool them before they can be used covered small heat-insulated roofs. that leads into the earth shafts that the shafts

The earth container according to the invention offers opposite 35 surrounding earth when introducing the pre-cooled the well-known earth containers with proportionate liquid freezes almost instantaneously. To moderately large opening has the advantage that it can be used cheaply in the freezing of the ground The manufacturing process is because, in the case of small containers, there is a low temperature pre-cooled liquid from the fan is to pump out the container walls for freezing.

gen than with the known large containers, and that 40 It has been found to be advantageous that one for the cost of the canopy is reduced. A replacement of the liquid of high specificity Another important advantage is that the production weight is due to the low freezing liquid Manholes in frozen ground essentially point one between the two liquids Easier to carry out is used as excavations for floating separating membrane because so large earth containers. Finally, it is advantageous that the two liquids are mixed to a large extent the capacity of the soil container is easily avoided, can be enlarged. In suitable earth formations or layers of earth

If the group of earth shafts is in accordance with one of the preceding, a liquid with low freezing content can also be used Use advanced training of the earth point according to the invention and high density without first container divided into at least two subgroups, 50 drilling mud is used. This liquid from each well of each sub-group with a low freezing point is intended to coincide with that in the ground Do not mix the shaft of the same subgroup on the liquid being held and the liquid to be frozen and connected at the bottom, so it is to be bar.

possible to use at least two different liquefied gases as soon as the shaft walls are frozen and a

to store at the same time. 55 manhole is pumped out, it can be closed with a

A method according to the invention for making roof cover. Then he stands to record the of the earth container described is that ready to be stored liquefied gas, If necessary, you can see the walls of the shafts at small distances from each other

Drilling shafts in the ground during the drilling work with concrete, aluminum, stainless steel completely or partially with a liquid or comfortable steel 60. Lining. In most capacity of high specific gravity are filled, however, cases such a lining will not then pipeline unneeded after completion of the drilling work.

gene in the vicinity of the shaft walls in the liquid. The earth container according to the invention is on hand

lowers the shaft walls by circulating one of drawings on an embodiment Cooling liquid in the pipes for freezing 65 explained in more detail.

brings, then optionally the cooling liquid F i g. 1 shows a horizontal cross section, and

replaced by a heating fluid in order to reduce the at the F i g. 2 shows a vertical longitudinal section through

Pipelines within the shafts, optionally an earth container according to the invention.

In an earth formation 1 numerous earth shafts 2 are created, their depth in relation to its width is great. The shafts usually have a circular cross-sectional shape. The depth each earth shaft is about 30 m, while the diameter is about 3 m. The shafts are applied at small distances from each other. The one surrounding the earth shafts 2 and between adjacent ones Earth formation 3 present in wells contains a liquid in the solid state, at which is usually frozen water. At the top, open end of each shaft is 2 covered with a roof 4 made of aluminum, concrete, stainless steel, wood or a other suitable material may exist. To allow heat from the environment to penetrate prevent, heat-insulated roofs are expediently used. Instead of a curved one Roof 4, a flat roof 4 'can also be provided.

It is advantageous to equip each earth shaft 2 with its own roof 4. However, it is fundamental also possible to use a larger roof that covers several shafts 2, but that is Use of a separate roof for each earth shaft is therefore particularly advantageous because it is then only has to span a relatively small opening and is therefore of relatively light and simple construction can be.

The earth container allows each earth shaft to be used individually. However, it is also possible the individual earth shafts below through an opening 5 and above through an opening 6 with each other connect to. This offers the advantage that only one pipeline is required for a subgroup of underground shafts 2 for filling and emptying and only one venting device is required. It is useful that Subdivide group of earth shafts into at least two subgroups, with each shaft one each subgroup above and below through openings 6 and 5 with another shaft of the same Subgroup is connected. In this way, each sub-group forms a separate storage unit, the can be filled and emptied separately. It is also possible to use different subgroups in the separate subgroups To store liquefied gases, e.g. B. liquefied natural gas in one and liquefied methane in another. Of course, more than two subgroups can also be formed, so that if necessary more than two can store different liquefied gases at the same time.

In FIG. 2, only the openings 5 are shown as an example 6 and 6, which connect two adjacent earth shafts 2 to one another. In the same way are others Earth shafts can be connected to one another.

The upper parts of the shaft walls can in the manner shown in FIG. 2 at 7 indicated manner made of concrete in order to prevent the shaft walls from collapsing there, these concrete walls at the same time Form a solid foundation for the roofs 4 and 4 '. The upper connection opening 6 can be in the Concrete wall 7 be formed. The lower connection opening 5 is preferably made with a tube 8 lined to prevent erosion of the soil.

Claims (5)

Patent claims: 1. Earth container for storing liquefied gases at low temperatures in one of the containers surrounding earth formation, which contains a liquid that solidifies at low temperatures and remains solid when the container is filled with the liquefied gas to be stored, wherein the underground container with facilities for filling, emptying and venting the liquefied gas and is provided with a cover that insulates against heat, characterized in that that the container is designed in the form of a group of vertical earth shafts, which are in the earth's surface at small intervals arranged from each other and optionally with each other at their upper and lower Ends are connected. 2. Earth container according to claim 1, characterized in that the group of earth shafts is divided into at least two subgroups, each shaft of each subgroup with one is connected to another shaft of the same subgroup at the top and bottom. 3. A method for producing an earth container according to claims 1 and 2, characterized in that that several shafts are drilled into the ground at small intervals, which during the drilling work wholly or partially with a liquid of high specific weight are filled, then after completion of the drilling work pipelines in the vicinity of the The shaft walls are lowered into the liquid, the shaft walls through the circulation of a cooling liquid freezes in the pipes, then the coolant if necessary Replaced by a heating fluid, if necessary to the pipelines inside the manholes melt frozen liquid, and finally the piping removed the liquid pumps out of the shafts and these with one or more insulating against heat Covers. 4. A method for producing an earth container according to claim 1 or 2, characterized in that that the liquid contained in the shafts after completion of the drilling work of high specific gravity replaced by a liquid with a low freezing point and the latter liquid after freezing the well walls by the circulation a liquid in the pipelines and after the pipelines have been removed from the manholes pumps. 5. The method according to claim 4, characterized in that to replace the liquid of high specific weight one floating between the two liquids Separating membrane used. Considered publications:
U.S. Patents Nos. 2,437,909, 2,687,618,
2961840. 1 sheet of drawings 809 S68 / 211 6.68 © Bundesdruckerei Berlin