FR2485160A1 - BACKGROUND FOR LIQUEFIED LIQUEFIED GAS STORAGE INSTALLATION, AND METHOD FOR CONSTRUCTING LAND STORAGE FACILITY - Google Patents

Abstract

THE INVENTION CONCERNS A STORAGE INSTALLATION FOR LIQUEFIED GAS SPHERICAL TANKS INTENDED TO BE PLACED ON LAND. THE SPHERICAL STORAGE TANK 50 IS SUPPORTED BY A SKIRT 49 INSIDE A CONCRETE SILO 51 SURROUNDING IT. AN ADVANTAGEOUS MATERIAL OF PRODUCING THE STORAGE FACILITY RESIDES IN THE FACT THAT THE CONCRETE SILO OR ITS LOWER FLOATING PART ARE PRODUCED IN A WEAPON BASIN AT THE SAME TIME AS THE SPHERICAL TANK, AFTER WHICH IT IS TRANSPORTED BY DOING IT FLOAT TO A LOCATION NEAR THE EARTH PLACEMENT SITE, THE INSTALLATION BEING RAISED ASHORE THANKS TO THE PRINCIPLE OF THE USE OF SEVERAL LOCK SAS. THE INVENTION APPLIES IN PARTICULAR TO LIQUEFIED NATURAL GAS TREATMENT PLANTS.

Description

The present invention relates to an installation of.

  Storage with spherical storage tanks for LPG

  established for use on earth. The invention also relates to a practical method for producing a similar spherical storage tank storage facility for

  liquefied gas intended to be mounted on earth.

  Liquefied gas storage tanks of a

  terrestrial installation must satisfy a number of conditions

  particularly in the case of LNG (liquefied natural gas).

  For example, heat transfer to

  tank is minimal, that is to say that there is a thick insulation.

  In addition, the installation must be well protected against humidity due to large differences in temperature. Reservoirs must also be protected against actions of the external environment such as temperature variations, earthquakes, wind, precipitation, etc., and such liquefied gas storage tanks installed on land must also be protected against and other external actions, such as, for example, junctions. "Another important condition to be satisfied is that in a certain number of cases it is necessary to provide a means which acts as a" secondary container ", that is, to ensure that liquefied gas that has escaped from the tank will be collected,

  in case of leakage or rupture of the main tank.

  These requirements are the level of security and operational reliability of the facility. In addition to these factors, it is necessary to take into account data such as

  of construction and operation, simplicity and speed of

  construction, etc. Recently, the desire to find a simple method of building such installations, requiring only limited personnel at the assembly or installation site, has been specially formulated. This wish can be achieved by prefabrication. A particular advantage of using spherical tanks as storage tanks is their high degree of safety and reliability. Much of the experience gathered comes from the use of these containers in marine applications. A particular advantage is that

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  the tank support does not require significant isolation

  above ground level, as is the case when large

  Vertical cylindrical tanks with flat bottom.

  It is proposed, according to the invention, to form the subbasis

  spherical tanks supported by a skirt-shaped rim using a floating unified concrete body. It is thus possible to produce the basement in a practical way in one site

  appropriate building, for example a basin, and then transport it

  by floating it on the water to the vicinity of its final destination, where it is then pulled to the ground, either by means of skates or, preferably, by application of the principle using a group of

several lock chambers.

  A particularly advantageous feature is

  in that the base itself can serve as a barge for trans-

  Harbor. In this case, the entire installation, including the spherical tanks, can be constructed in a basin, floated, faded on the water to a location near the assembly site, where it is then drawn ashore. , preferably by means of

  of the principle using a group of several lock chambers.

  The invention is particularly well suited, first and foremost, to use in the context of relatively large gas treatment plants,

  for example, liquefied natural gas

  petrochemical installations, etc., which, because of the obligation to ship, are located on

an appropriate coast.

  Preferably, the base is made of a wall

  of one-piece vertical concrete intended to constitute the

  lower load support tie of the skirt-shaped support edge. This wall also defines a compartment for collecting leaks. As external protection, a steel or concrete silo can be built around the spherical tank. Optionally, it is possible to build and

  to mount this silo on the same place of construction of the basement.

  To reduce the draft of the concrete body

  a number of measures can be taken: the most obvious would be to adopt as much

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  -3 buoyancy by maximizing the value of the surface and choosing for the concrete structure solutions to save

the weight.

  The silo will provide protection against wind and weather, as well as other external effects, such as

  than those of flying objects (missiles). The silo can also

  additional protection against moisture, as the atmosphere is kept dry. Inside the silo, we

  can provide platforms, ladders and walkways -

  inspection purposes. The silo can also be used as a container

  secondary or collection tank in case of rupture of the

  * see main (the spherical tank). An advantage resulting from the use of such a silo as a secondary container, if necessary, is that the evaporation-is limited by the surface

  of the secondary container, and that the damage is now

  kept in a limited area. In case of leakage from the main tank, it is possible to make the space inert so as to reduce the

fire and explosion hazards.

  The roof of the silo can be a light structural structure or a lady with the same strength as the walls or a

  - superior resistance. The spherical reservoir can be supported by

  below by means of a conventional reinforced skirt type border, or it can be suspended in a weakly conical structure loaded in tension, for example by the combination of a short

  skirt with suspension struts distributed around its circumference

ference.

  The following description, designed as an illustration

  invention aims to provide a better understanding of.

  its features and benefits; it applies to the accompanying drawings, among which: - Figure 1 shows a simplified sectional view of a partially completed storage installation structure in a docking pool, ready to leave the site; FIG. 2 represents a simplified sectional view of a second embodiment of a storage facility structure in an armament pool, ready to leave the worksite;

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4 -

  FIG. 3 represents a third embodiment of

  possible, ready to leave an armament basin; FIG. 4 shows how the principle of the lock chamber can be used to raise a structure of the type shown in FIG. 3 and bring it to the ground; - Figure 5 shows a structure of the type shown in Figure 1, disposed on the mounting site, its silo having been partially built but waiting to be completed; FIG. 6 represents a structure of the type illustrated in FIG. 2, installed on the ground; FIG. 7 represents a structure of the type illustrated in FIG. 3, installed on the ground;

  FIGS. 8 and 9 represent two possible sets

  respectively formed of two and three spherical tanks, inside a common concrete silo; - Figure 10 illustrates how to maximize the value of the surface to reduce the draft; and - Figure 11 shows a structure, in section and in

  perspective o the basement is a closed-box type body.

  In the docking basin 1 shown in FIG. 1, whose water level is designated by the reference 2, the lower part 3 of a concrete silo is constructed. In this case, the concrete bottom 4 and a concrete skirt 5 are molded, then a spherical tank 6 is mounted on the concrete skirt via a skirt 7 loaded in compression. The skirt 7 and the spherical tank 6 are preferably of the type known in marine applications, that

  the professionals designate by the abbreviation "bRV".

  In this case, the concrete skirt 5 is advantageously used as the wall of the floating silo part 3, so that

  the structure of Figure 1 can be taken out of the weapon basin

  on the waters. Optionally, the silo wall that will be produced later can already be started at this stage of construction, as indicated by the line line.

interrupted under the reference 8.

  Figure 2 shows how the construction can be completed.

  the entire storage facility in an arming basin 9, the water level of which is designated by reference number 10. A mold is

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  concrete silo 11 integrally provided with a bottom 12 and a d8me-13 concrete in the docking tank, the storage tank 14 is also installed at the same time. The storage tank 14 is mounted in the concrete silo in the same manner as in the embodiment of FIG. 1. FIG. 3 shows how a concrete silo 15 is constructed in an arming basin 16, the level of which of water is

  17e In contrast to the pre-existing concrete silos

  1 and 2, the bottom 18 of concrete is in this case of a convex configuration, and the remainder of the concrete silo has the

  shape of a vertical cylinder. This type of silo is intended to

  see a roof or cover in the shape of a structure of

  light frame (not shown).

  In this embodiment, a spherical tank 19 is suspended in the silo 15 via a structure 10 in the form of a slightly conical skirt loaded with tension. In this context, the expression "skirt-shaped structure" should be understood as consisting of combinations of skirts and tension-loaded struts or bolts, or, optionally, in the strict sense of a suspension consisting of struts. these stay cables being distributed

on the circumference.

  The concrete silo and the spherical reservoir associated with a suspended structure can both be produced by known techniques, so that it does not appear.

  necessary to continue their description in detail.

  However, it should be mentioned that the spherical tanks can advantageously be made of a suitable material of the type

  steel or, preferably, of a suitable aluminum alloy.

  spherical tank is insulated in a known manner, and the insulator is covered with a vapor control device in form

  aluminum foil or other suitable material.

  After the storage facility structure has been erected to the point indicated in FIGS. 1, 2 or 3, respectively, the pools 1, 9 or 16 respectively are filled with water;

  the structure then floats and can be transported

  in a location near the assembly site, ie the concrete silo or its floating part is used as a barge 6-

transport.

  Figure 4 shows how a concrete silo and its associated spherical tank can be lifted using a set of several lock chambers. The structure illustrated in FIG. 4 is identical to that shown in FIG. 3. The structure 15 is first placed in an airlock 21. The airlock 21 is then closed and filled with water to the level 22. then opens the airlock 23 and the structure 15 is passed into it. The airlock 23 is then closed and filled with water to level 24, and the structure is moved into the upper part of the airlock 23, which in this case represents the mounting site. We then go down

  the structure 15 in contact with the ground by evacuating the water from the lock 23.

  FIG. 5 represents a structure of the type illustrated in FIG. 1, installed in a mounting site, for example an upper airlock, or in an airlock communicating directly with the sea. The assembly site is delimited by means of a wall 26 and fills the airlock with a filling mass 27. Then continues the assembly of the partially completed wall 8 of the concrete silo, as indicated by the dashed lines so as to produce a finished concrete silo of the type shown in Figure 2 for example. Naturally, we can build the silo

  concrete in the form of a cylindrical wall, as is

  shown in Figure 3, and provide it with a suitable roof or cover,

  preferably in the form of a light framework structure.

  Figures 6 and 7 show structures respectively having the types of Figures 2 and 3, after implementation

  at the assembly site, in the same way as for Figure 5.

  In FIG. 6, a wall is designated by the reference 28, and the material forming the filling mass by the reference 29. On

  7, the wall is indicated by the reference 30 and the material

  the filling mass by the reference 31.

  FIG. 8 shows how two spherical tanks 32, 33 can be joined inside a single concrete silo 34, and FIG. 9 shows three spherical tanks 35, 36, 37 grouped inside a silo of concrete 38 common. These two embodiments can in principle be made in the manner presented for example in FIGS. 1, 2 and 3.

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  7 - reference 39 and 40 designate low walls starting from the bottom of

  silo and used to increase buoyancy.

  Figure 10 shows how one can make maximum

  the value of the surface to reduce the draft of the structure.

  The extended area 41 associated with a low wall 42 allows a maximization of the value of the surface and a reduction of the draft. The

  wall 42 defines a compartment 43 which can, optionally

  stay empty until immediately before the installation

  lation and / or anchorage. The wall pockets the water to enter

  during the installation phase. The superficial area may be circular

  rectangular, oval, etc., depending on the installation site

  tion. In FIG. 10, the skirt 44 and the reservoir 45 are simple-

suggested.

  The storage facility shown in Figure II

  has a bedrock or floating body in the form of a compartment

  closed or barge 46 of concrete. From the bridge-47, rises a concrete integral wall 48 which acts as a lower weight support part of the supporting skirt, -which also comprises the skirt 49. Around the spherical tank 50, is constructed, in this case

in particular, a steel silo 51.

  In addition to the advantages mentioned above relating to the use of a base that is built in the form of

  floating body and which subsequently forms part of the

  storage, the invention also makes it possible to move

  Once the installation has been completed, it must be completed at the installation site, ie after 15 to 25 years. Both the stick and the aluminum are, for the purpose being considered, very durable materials, and these storage tanks with scrapings have a much longer economic life than that of the gas treatment plant itself. even. Thus, in addition to satisfying a desire, and a need, more and more important, that one can "perform the cleaning after the fact" once the activity is over, these tanks and silos can

in addition be reused.

  The spherical tanks associated with a silo

  an entity, including both a main reservoir and a secondary reservoir (where necessary),

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  8- insulation, protection, inspection and maintenance, pumps and safety valves, instruments, etc. The installation can furthermore be entirely prefabricated, that is to say contain all the elements mentioned above, and when moved to a new site, all the secondary and auxiliary systems are moved with it. The spherical tank supported by a skirt, in addition to not requiring significant isolation vis-à-vis the ground, does not require means providing heat, as is the case for some systems. Inspections and repairs can be done immediately, and there is no need to wait for months for the tank space

insulation is gas-free.

  A number of the most promising gas processing facilities are or may be

  find in seismically active areas. Spherical tanks

  such as aluminum, supported in non-stationary silos, can withstand extremely high vibration without breaking, and the safety of the system with respect to the catastrophic consequences of earthquakes does not depend on

  general and extensive seismic surveys of the region.

  On the basis of what has just been stated, we understand

  that the invention proposes an "available flattering body" combined with a base which is usefully employed both during construction and, later, as a permanent base. The floating body may be a bottom surface having reservoir sides, or an extended bottom surface having

  sides erected vertically. The floating body can be complete

  closed, or open at the top.

  - It is possible to use other structural elements

  The main functions differ from those used to limit a floating body, while it is possible to strengthen the boundary surfaces to perform certain functions as parts of a heavily loaded base. For example, the bottom can

  have a domed configuration or a honeycomb structure.

  Of course, those skilled in the art will be able to imagine,

  from the devices and the process whose description comes from

  to be given merely illustrative and not limiting, various other variations and modifications not outside the scope of the invention.

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Claims (6)

R E V E N D I C A T I 0 N S   1 - Underbody for one or more spherical tanks   (6; 14; 19) of liquefied gas supported by a skirt-like border belonging to a storage installation intended to be placed on the ground, the base being characterized in that it is constituted in the form of a unified concrete body floating (3; 11; 15).   2 - Underbody according to claim 1, characterized in that the floating concrete body (3; 11; 15) comprises a wall (5; 13) made of vertically fixed solid concrete which serves as a part   lower load support for the support () in the form of a skirt.   3 - A method of producing a land storage facility having one or more spherical tanks (6; 14; 19) of liquefied gas supported by a skirted border, which are arranged on a bedrock, the method being characterized in that a buoyant unified concrete body (3; 11; 15) is made, floated, and transported by floating on the water to a location near the final emplacement site on earth, after which it is put on the ground and used to serve from this bedrock.   4 Process according to claim 3, characterized in that the spherical tank or tanks are mounted, by the so-called skirt support technique, on the floating concrete body before said transport on the water.   5 - Process according to claim 3, characterized in that the transfer of the body to the site of establishment on land is done using the principle using a group of several lock chamber.   6 - Process according to claim 3, characterized in that the solidly floating concrete body is molded integrally with a wall (5; 13) made of vertically standing concrete, in order that it serve as a lower part of the support support of the support (7) spherical tank skirt type.