Sealed and thermally insulating tank

Abstract

A sealed and thermally insulating tank comprising: a sealing membrane intended to be in contact with the fluid to be stored, a thermally insulating barrier comprising a plurality of insulating blocks placed side by side, an insulating block comprising: a polymer foam layer, an inner sheet bonded against the polymer foam layer and having an upper surface supporting planar portions of the sealing membrane, the inner sheet comprising a housing, a metal anchoring support positioned in the housing, the metal anchoring support being movable transversely to the thickness direction of the tank wall, the anchoring support comprising a top portion and a base, and a cover attached to the insulating block and comprising a through-hole (881) inside which the top portion is positioned, the cover covering the base of the anchoring support so as to hold the anchoring support in the housing in the thickness direction.

Description

Waterproof and thermally insulating tank

[0001] The invention relates to the field of sealed tanks and more particularly to sealed and thermally insulating membrane tanks. In particular, the invention relates to the field of sealed and thermally insulating tanks for the storage of liquefied gas at low temperature, such as tanks for the storage of Liquefied Natural Gas (LNG) at approximately -162°C at atmospheric pressure. These tanks can be installed on land or on a floating structure. In the case of a floating structure, the tank can be intended for the transport of liquefied gas or for receiving liquefied gas used as fuel for the propulsion of the floating structure. Technological background

[0002] Well known in the prior art are sealed and thermally insulating tanks integrated into supporting structures to serve as a land-based or floating storage facility, comprising one or more thermally insulating barriers and one or more sealed membranes. For example, such tanks comprise a secondary thermally insulating barrier, a secondary sealed membrane, a primary thermally insulating barrier and a primary sealed membrane. The tank comprises a plurality of tank walls assembled together.

[0003] In such a tank, the waterproof membrane in contact with the fluid (primary waterproof membrane) must be able to withstand forces generated by thermal contraction, hydrostatic pressure, possible movements of the stored fluid, and bending of the ship beam in waves if necessary. For this, it is common to provide a corrugated metal waterproof membrane. The corrugations are capable of deforming locally and thus allow the forces to be absorbed without damaging the waterproof membrane.

[0004] However, it is necessary to locally interrupt the corrugations of the waterproof membrane to allow the installation or passage of equipment in the tank. For example, the passage of a pipe through the membrane or the installation of a sump requires interrupting the corrugations, for example as illustrated in WO-A-2020193665. In the vicinity of this equipment, the waterproof membrane is therefore more rigid than elsewhere but still subject to stresses. Thus, in these locations, the waterproof membrane is more rigid and risks concentrating stresses. Summary

[0005] One idea behind the invention is to improve the capacity of a corrugated waterproof membrane to absorb stress by means of a mobile anchoring support.

[0006] For this purpose, according to one embodiment, the invention provides a sealed and thermally insulating tank for storing a fluid, the tank comprising a tank wall intended to be fixed to a supporting structure, the tank wall comprising, in a thickness direction: a sealed membrane intended to be in contact with the fluid to be stored, the sealed membrane being metallic and having corrugations and flat portions located between the corrugations, and a thermally insulating barrier arranged between the sealed membrane and the supporting structure, the thermally insulating barrier comprising a plurality of juxtaposed insulating blocks, an insulating block of the thermally insulating barrier comprising: a layer of polymer foam, an internal plate bonded against the layer of polymer foam and having an upper surface supporting flat portions of the sealed membrane, the internal plate comprising a housing,a metal anchor support positioned in the housing, the metal anchor support being movable transversely to the thickness direction of the tank wall, the anchor support comprising a top portion, and a base wider than the top portion and arranged between the top portion and the polymer foam layer, and a cover fixed to the insulating block and comprising a through-hole inside which the top portion is positioned, the cover covering the base of the anchor support so as to maintain the anchor support in the housing in the thickness direction of the tank wall, an upper surface of the cover being flush with the upper surface of the internal plate, a flat portion of the waterproof membrane being welded to the top portion of the anchor support.,

[0007] Thus, thanks to these characteristics, this anchoring support can be positioned and used to fix the waterproof membrane in the regions of the wall in the vicinity of the interruptions of corrugations in order to give flexibility to the waterproof membrane. For example, the anchoring support is used at a distance of less than three wave steps from the penetrating element. Thus, the waterproof membrane being welded to the anchoring support, it benefits from the mobility of the latter and can therefore absorb the shear forces to which it is subjected thanks to this mobility.

[0008] Another advantage conferred by the invention is the possibility of detecting and removing any excess glue located inside the housing on the polymer foam layer following the bonding of the internal plate against it. By removing such excess glue before the anchor support is placed in the housing, it is ensured that such excess glue cannot undesirably hinder the mobility of the anchor support in the housing.

[0009] According to embodiments that can be combined with each other, it is possible to provide one or more of the following different characteristics.

[0010] According to one embodiment, the housing of the internal plate comprises a central portion receiving the base and a counterbore surrounding the central portion and having a shallower depth than the central portion, the cover being fixed to the internal plate in the counterbore.

[0011] This counterbore allows the cover to be fixed to it. The fixing is then better since the fixing is carried out on a surface of the cover which can be more rigid than the polymer foam layer.

[0012] According to one embodiment, the top portion is flat and continuous.

[0013] In one embodiment, the cover is attached to the polymer foam layer and the cover has a thickness such that the cover is flush with the upper surface of the inner plate.

[0014] According to one embodiment, a lower surface of the cover comprises a counterbore surrounding the through hole and receiving the base of the anchor support and a support portion surrounding the counterbore and fixed to the polymer foam layer at the bottom of the housing.

[0015] According to one embodiment, the anchor support is hollow. This saves weight and cost. In addition, this limits thermal bridges between the insulating barrier and the waterproof membrane.

[0016] According to one embodiment, a depth of the anchor support is such that the top portion of the metal anchor support is flush with an upper surface of the inner plate. The depth is defined as the distance between the base and the top portion of the anchor support in the thickness direction of the tank wall. Thus, it is determined so that the top portion and an upper surface of the inner plate are contained in a same plane. Thus, the anchor support is entirely contained in the housing.

[0017] According to one embodiment, the base of the anchoring support has a larger dimension, for example a width, less than a larger dimension, for example a width, of the housing or the counterbore and the top portion has a larger dimension, for example a width, less than a larger dimension, for example a width, of the through hole.

[0018] The largest dimension of the base can be its width or its length or its diameter. The largest dimension of the housing or the through hole can be a width, a length or a diameter. This ensures reliable mobility of the anchor support.

[0019] Thus, the range of transverse mobility of the anchor support can be determined by sizing the largest dimension of the housing, counterbore or through hole of the cover.

[0020] According to one embodiment, the thermally insulating barrier further comprises a thermal protection sheet adhered to the polymer foam layer at the bottom of the housing, the base of the anchoring support being positioned on the thermal protection sheet.

[0021] Such thermal protection protects the polymer foam layer from excessive heating when welding the waterproof membrane to the anchor support.

[0022] According to one embodiment, the thermal protection sheet comprises fiberglass. Thus, the thermal protection sheet exhibits satisfactory sliding and does not unduly hinder the mobility of the anchor support.

[0023] According to one embodiment, the cover is fixed by screwing, stapling or gluing, in particular in the counterbore of the cover or on the layer of polymer foam.

[0024] According to one embodiment, the anchoring support is located in the vicinity of a through element which passes through the tank wall in the thickness direction.

[0025] In other words, the insulating block to which the primary membrane is welded is located near an element passing through the tank wall. In such places, the membrane corrugations are interrupted. Such a passing element can be, for example, a sump, a pipeline, a support for a loading tower, etc.

[0026] According to one embodiment, the waterproof membrane is a primary waterproof membrane, the thermally insulating barrier is a primary thermally insulating barrier and the insulating blocks are primary insulating blocks, and the tank wall further comprises a secondary thermally insulating barrier located against the supporting structure and also comprises a secondary sealing membrane located between the secondary thermally insulating barrier and the primary thermally insulating barrier.

[0027] According to another aspect, the invention also provides a method of manufacturing a sealed tank comprising the following steps:

[0028] - bonding an internal plate against a layer of polymer foam of an insulating block of the thermally insulating barrier, the internal plate comprising a housing;

[0029] - if excess glue overflows onto the polymer foam layer during or after the gluing step, remove this excess glue,

[0030] - positioning a base of an anchoring support in the housing on the polymer foam layer, the anchoring support comprising:

[0031] - the base, and

[0032] - a continuous summit portion;

[0033] - covering the base of the anchor support with a cover, the cover comprising a through hole, such that the continuous top portion is positioned inside the through hole and the cover covers the base of the movable metal anchor support so as to hold the movable anchor support in the housing in a thickness direction of the insulating block,

[0034] - weld a waterproof membrane to the continuous top portion of the anchor support.

[0035] Thanks to these characteristics, it is possible to check whether the bonding step does not generate excess glue at the boundary between the polymer foam layer and the internal plate. This potential excess glue could hinder or even prevent the mobility of the anchoring support within the housing of the internal plate. Thus, according to the proposed manufacturing process, it is possible to prevent such a potential defect.

[0036] According to one embodiment, the invention provides an intermediate step before the step of positioning the base of the anchoring support on the layer of polymer foam.

[0037] This intermediate step consists of gluing a thermal protection sheet onto the polymer foam layer at the bottom of the housing. The base of the anchor bracket is then positioned on the protective sheet. It is then in direct contact with the protective sheet and rests on the polymer layer.

[0038] According to another aspect, the invention also provides a land-based installation for storing a liquefied gas comprising a sealed and thermally insulating tank mentioned above.

[0039] Such a tank can be part of a land-based storage facility, for example for storing LNG, or installed in a floating, coastal, or deep-water structure, including an LNG carrier, a floating storage and regasification unit (FSRU), a floating production and offshore storage unit (FPSO), and others. Such a tank can also serve as a fuel tank in any type of vessel.

[0040] In addition to LNG, the land-based storage facility can be used to store argon, methane, ammonia, air, carbon dioxide in liquid form (with potentially a portion in gaseous form).

[0041] According to another aspect, the invention also provides a vessel for transporting a cold liquid product, the vessel comprising a double hull and a aforementioned sealed and thermally insulating tank arranged in the double hull.

[0042] According to another aspect, the invention also provides a transfer system for a cold liquid product, the system comprising the aforementioned vessel, insulated pipes arranged to connect the vessel's tank to a floating or land-based storage facility and a pump for driving a flow of cold liquid product through the insulated pipes from or to the floating or land-based storage facility to or from the vessel's tank.

[0043] According to another aspect, the invention also provides a method of loading or unloading a ship, in which a cold liquid product is conveyed through insulated pipes from or to a floating or land-based storage facility to or from the tank of the aforementioned ship. Brief description of the figures

[0044] The invention will be better understood, and other objects, details, characteristics and advantages thereof will appear more clearly during the following description of several particular embodiments of the invention, given solely for illustrative and non-limiting purposes, with reference to the accompanying drawings.

[0045] This is a schematic, cut-away representation of a land-based storage facility.

[0046] This is a perspective view of a tank wall near an area where the corrugations of a waterproof membrane are interrupted.

[0047] This is an enlarged cutaway view of portion III of which an anchor support is illustrated.

[0048] This is an exploded perspective view of an insulating barrier comprising a movable anchoring support according to a first embodiment, suitable for use in the tank wall of the.

[0049] La is a perspective sectional view along the VV axis of la showing the anchor support of the first embodiment in an assembled state.

[0050] This is an exploded perspective sectional view of an insulating barrier comprising a movable anchoring support according to a second embodiment, which can be used in the tank wall of the.

[0051] This is a perspective sectional view of the second embodiment.

[0052] This is an enlarged view of portion VIII of which a chamfer of a cover is illustrated.

[0053] This is a schematic cutaway representation of an LNG tank and a loading / unloading terminal for this tank.

[0054] The invention will be described below in connection with a liquefied gas storage facility. The facility is capable of storing liquefied gas, in particular liquefied natural gas (LNG) at a temperature of approximately -162°C and at atmospheric pressure or other liquefied gases. The facility may also be capable of storing other types of liquid, in particular at ambient temperature.

[0055] The installation mainly comprises a supporting structure 10 and a sealed and thermally insulating tank 20 installed in an internal space of the supporting structure 10, according to the known technique.

[0056] The installation may be a land-based installation shown in the figure. The supporting structure 10 then comprises a bottom supporting wall 11 and a vertical supporting wall 12. The bottom supporting wall 11 is then typically horizontal, i.e. located in a plane perpendicular to the direction of the acceleration of gravity, within dimensional tolerances. The bottom supporting wall 11 may be located at ground level or possibly below ground level. The supporting structure 10 is, for example, made of concrete.

[0057] The tank 20 comprises a bottom wall 21 arranged on the bottom load-bearing wall 11, and a vertical wall 22 arranged on the vertical load-bearing wall 12.

[0058] Alternatively, the installation may be intended to be installed on board a floating structure, such as an LNG carrier 70 as illustrated in. In this case, the supporting structure 10 is a portion of a double hull 72 belonging to the floating structure. The general geometry of the tank may also be of different types. Polyhedral geometries are the most common.

[0059] Regardless of the geometry of the tank, one or each tank wall has a multi-layer structure successively including a secondary thermal insulation barrier fixed to the load-bearing wall, a secondary waterproof membrane supported by the secondary thermal insulation barrier, a primary thermal insulation barrier covering the secondary waterproof membrane and a primary waterproof membrane supported by the primary thermal insulation barrier. The primary waterproof membrane is intended to be in contact with the liquefied natural gas contained in the tank.

[0060] The bottom wall 21 and the vertical wall 22 can be made using modular elements. In the embodiment described here, these modular elements correspond to the GST® technology marketed by the applicant, for example. Reference may also be made to document US 6,035,795 for the description of certain modular elements.

[0061] Also by way of example, such membrane tanks are described in particular in patent applications WO2019239048, WO14057221, FR2691520 and FR2877638.

[0062] Thus, thermally insulating barriers can be made in many ways, from many materials. The secondary thermally insulating barrier comprises a plurality of secondary insulating panels which are anchored to the load-bearing wall by means of retaining devices (not shown) known elsewhere. The primary thermally insulating barrier also comprises a plurality of primary insulating panels which are fixed to the secondary insulating panels or to the load-bearing wall by means of retaining devices (not shown).

[0063] The insulating panels of these thermally insulating barriers together form flat support surfaces for the waterproofing membranes. Such insulating panels are, for example, made of polyurethane foam blocks. Such insulating panels made of polyurethane foam blocks may additionally comprise a cover plate and / or a base plate, for example made of plywood.

[0064] According to one embodiment, the secondary waterproofing membrane is formed from a composite material comprising an aluminum sheet sandwiched between two sheets of fiberglass fabric. The primary waterproofing membrane is obtained by assembling a plurality of corrugated metal sheets, welded to each other along their edges, and comprising corrugations extending in two perpendicular directions, namely a first series of corrugations and a second series of corrugations. The two series of corrugations may have regular spacing or periodic irregular spacing. The metal sheets are, for example, made from stainless steel or aluminum sheets, shaped by folding or stamping.

[0065] Further details of such a corrugated metal membrane are described in particular in FR2861060.

[0066] In another embodiment, the secondary waterproofing membrane may also comprise a continuous sheet of metal strakes, with raised edges. The strakes are welded by their raised edges to parallel welding supports which are fixed in grooves provided on the cover plates of the secondary insulating panels. The strakes are, for example, made of Invar ®: that is to say an alloy of iron and nickel whose coefficient of expansion is typically between 1.2.10 -6 and 2.10 -6 K -1 It is also possible to use iron and manganese alloys whose coefficient of expansion is typically in the order of 7 to 9.10 -6 K -1 .

[0067] In particular, according to an embodiment illustrated in , the waterproof membrane 5 in contact with the stored fluid contains undulations 26a, 26b and flat portions 60 between the undulations 26a, 26b. These are distributed parallel to each other in a longitudinal direction and a transverse direction of the wall: the undulations 26a are distributed in the longitudinal direction and the undulations 26b are distributed in the transverse direction.

[0068] The corrugations 26a and 26b allow the waterproof membrane 5 in contact with the stored fluid to absorb the forces generated. Indeed, the corrugations 26a, 26b give flexibility to the waterproof membrane 5.

[0069] It more particularly represents a particular zone of the wall 21 or 22 where the waterproof membrane 5 is more rigid.

[0070] In such an area, equipment (for example a sump or a pipe) creates a discontinuity in the waterproof membrane 5. This discontinuity takes the form, for example, of a pipe 17.

[0071] Around the location of the pipe 17, the corrugations 26a and 26b are interrupted and the waterproof membrane 5 becomes flat, or at least substantially flat, over a portion of the wall.

[0072] The equipment is continuously connected to the waterproof membrane 5 using a metal closure plate 23, the equipment and the metal closure plate 23 thus sealingly completing the waterproof membrane 5.

[0073] The metal closure plate 23 is for example composed of two portions welded to each other by overlapping. An inner edge of the metal closure plate 23 is welded in a sealed manner, that is to say with a continuous weld bead, to a first rim 19 all around a side wall 18 of the pipe 17. In addition, the metal closure plate 23 has an outer edge 25 placed under the waterproof membrane 5 so as to form an overlap zone, as shown in. Caps 27 cover the ends of the corrugations 26a and 26b in order to weld them to the metal closure plate 23. The metal closure plate 23 is thus welded in a sealed manner with the waterproof membrane 5 at the overlap zone.

[0074] Preferably, the metal closure plate 23 is not fixed to the thermally insulating barrier. The metal closure plate 23 has, in this embodiment shown, a square shape.

[0075] This area remains subject to forces to which the wall is subjected at every point of its surface. However, since the corrugations 26a and 26b are no longer present, this portion of the waterproof membrane 5 is more rigid.

[0076] There is therefore a risk of increased deterioration threatening the sealing or the lifespan of the installation in this area.

[0077] To overcome this technical problem, the disclosure proposes two embodiments of an anchoring system for anchoring the waterproof membrane 5 in a movably manner to the insulating blocks of the insulating barrier and more particularly at the level of the flat portions 60 in the vicinity of the overlap zone.

[0078] In the, an insulating block 9 of the thermally insulating barrier is partially shown. This contains a polymer foam layer 41, for example glass fiber reinforced polyurethane, and an inner plate 42. The inner plate 42 is bonded against an upper surface (according to a thickness direction E of the wall and the insulating block 9) of the polymer foam layer 41.

[0079] The internal plate 42 can be made of plywood.

[0080] The internal plate 42 comprises a housing 14 comprising a central portion 13 which opens onto the polymer foam layer 41. According to this embodiment, the housing 14 comprises a counterbore 911 surrounding the central portion 13. This counterbore 911 has a shallower depth than the central portion 13.

[0081] A metal anchoring support 93 is positioned in the central portion 13 against the polymer foam layer 41, with the possible interposition of a thermal protection sheet 92. This anchoring support 93 comprises a base 931 and a top portion 932. The base 931 is positioned in the central portion 13 against an upper surface of the polymer foam layer 41 or possibly against the thermal protection sheet 92.

[0082] The top portion 932 is continuous, i.e. does not include any hole or orifice, so that it can be welded at any point to a flat portion 60 of the waterproof membrane 5. This top portion 932 is intended to be welded to the waterproof membrane 5 of the wall.

[0083] The top portion 932 may be generally round in shape, i.e. have a round upper surface. However, any other shape is possible.

[0084] The base 931 is not fixed to the polymer foam layer 41, thus the anchoring support 93 is movable along the upper surface of the polymer foam layer 41 in all directions of the plane of this surface.

[0085] According to one embodiment, the anchoring support 93 is hollow.

[0086] According to one embodiment, a thermal protection sheet 92 is positioned between the base 931 of the anchor support 93 and the polymer foam layer 41.

[0087] The insulating block 9 also comprises a cover 8. The cover 8 comprises a through hole 881.

[0088] The cover 8 cooperates with the housing 14 so that an upper surface of the cover 8 is flush with an upper surface of the internal plate 42 once it is positioned in the counterbore 911 of the housing 14. In this embodiment, a depth of the counterbore 911 in a thickness direction of the insulating block 9 is identical to the thickness of the cover 8 so that an upper surface of the cover is flush with an upper surface of the internal plate 42 once it is positioned in the counterbore 911 of the housing 14.

[0089] The cover 8 then covers the anchoring support 93: the top portion 932 is positioned in the through-hole 881. Similarly, the thickness of the anchoring support 93, i.e. a distance between the base 931 and the top portion 932, is such that an upper surface of the anchoring support 93, i.e. of the top portion 932, is flush with an upper surface of the cover 8 and, therefore, of the internal plate 42. The anchoring support 93 is thus entirely contained in the housing 14.

[0090] The through-hole 881 has a cross-section of complementary shape with the shape of the top portion 932.

[0091] A maximum width of the top portion 932 in the plane of the surface of the inner plate 42 is less than the diameter of the through-hole 881. Thus, the cover 8 covers the movable metal anchor support 93 so as to stop the latter in the housing 14 in the thickness direction of the insulating block 9, and also so as to allow limited movement of the anchor support 93 in the plane of the upper surface of the polymer foam layer 41. The cover 8 can therefore also act as a stop for the top portion 932 via a lateral surface 811 of the through-hole 881.

[0092] The transverse movement of the anchor support 93 is also permitted by a gap between the base 931 and a lateral surface 100 of the central portion 13. If the distance between the contour of the base 931 and the lateral surface 100 of the central portion 13 is less than the distance between the contour of the top portion 932 and the lateral surface 811 of the through-hole 881 then the transverse movement of the anchor support 93 is limited by the central portion 13. Otherwise, the transverse movement of the anchor support 93 is limited by the through-hole 881.

[0093] The cover 8 is fixed to the insulating block 9. For example, it can be screwed (using screws 86 as illustrated in the), or stapled or even glued so that it is fixed, i.e. integral, with the insulating block 9.

[0094] In the embodiment illustrated in 5, in which the housing 14 comprises a counterbore 911, the cover 8 is screwed onto an upper surface of the counterbore 911 by screws 86 engaged in holes 87. It is therefore fixed in a more rigid material than the polymer foam layer 41.

[0095] Thus, the metal anchor support 93 is movable in the housing only parallel to the plane of the upper surface of the polymer foam layer 41.

[0096] The permitted displacement is for example between 1 and 10 mm.

[0097] The waterproof membrane 5 being fixed on the top portion 932 of one or more anchoring supports 93, it is also movable along the internal plate 42 against which it is positioned and fixed via the anchoring supports 93.

[0098] This mobility permitted by the mobility of the anchoring support(s) 93 allows the waterproof membrane 5 to be more mobile in the vicinity of the zone where it is less flexible, and thus to absorb the forces to which it is subjected. Preferably, the anchoring support 93 is used at a distance of less than three wave steps from the crossing element, for example the pipe 17. The anchoring support 93 can also be used at any location on the tank wall according to the needs of the intended application.

[0099] Figures 6 and 7 illustrate a second alternative embodiment of the invention. Only the differences between the second embodiment and the first embodiment previously described will be described.

[0100] However, it differs from this firstly in that the housing 14 does not include a counterbore 911.

[0101] It also differs from the first embodiment in that it comprises a cover 800 comprising a counterbore 82 on its lower surface. This counterbore 82 surrounds the through-hole 881 and covers or accommodates the base 931 of the anchoring support 93. The cover 800 also comprises a bearing portion 83 surrounding the counterbore 82. This bearing portion 83 is fixed to the polymer foam layer 41 located at the bottom of the housing 14.

[0102] Finally, it differs from the first embodiment in that the support portion 83 has a chamfer 801 at its outer end. This chamfer 801 makes it possible to receive any excess glue when the cover 800 is fixed to the polymer foam layer 41 by gluing.

[0103] Thus, the cover 800 is fixed to the insulating block 9 by being fixed to the polymer foam layer 41. Likewise, this fixing can be ensured by screwing, gluing or stapling.

[0104] In the, it is illustrated that the bearing portion 83 of the cover 800 is in contact with the polymer layer 41.

[0105] The embodiment of figures 6 and 7 provides the same advantages as the embodiment of figures 4 and 5: the waterproof membrane 5 is made locally more mobile and can therefore absorb the forces to which it is subjected thanks to its mobility permitted by the mobile anchor supports 93.

[0106] Another advantage of the invention appears at the (also conferred by the embodiment of the) in the enlarged region, namely portion VIII of the. Indeed, the internal plate 42 can be glued against the layer of polymer foam 41 during the manufacture of the insulating block 9.

[0107] This glue is likely to overflow onto a free portion, i.e. not covered by the internal plate 42, of the polymer foam layer 41 created by the housing 14. This excess would be likely to partially obstruct the housing 14 and therefore hinder or even prevent the mobility of the mobile anchoring support 93.

[0108] The embodiments of the invention make it possible to observe such an overflow when installing the anchoring support 93 and / or the cover 8 (or cover 800) and, if necessary, to remove the excess glue.

[0109] Illustrates the anchoring support 93 positioned on which the flat portion 60 is fixed. The hatched part represents the cover 8 or 800 visible through a cutaway representation of the flat portion 60. The top portion 932 is entirely visible through this cutaway representation and the base 931 is also partially visible through the through hole 881.

[0110] In an embodiment suitable for liquid, the secondary sealing membrane and the secondary thermally insulating barrier could be omitted.

[0111] The technique described above for producing a mobile anchor support in a primary thermally insulating barrier can also be used in different types of tanks, for example in a tank with a single sealed membrane, a double membrane tank for liquefied natural gas (LNG) in a land-based installation or in a floating structure such as an LNG carrier or other vessel.

[0112] The represents an example of a maritime terminal comprising a loading and unloading station 75, an underwater pipeline 76 and an onshore installation 77. The loading and unloading station 75 is a fixed offshore installation comprising a mobile arm 74 and a tower 78 which supports the mobile arm 74. The mobile arm 74 carries a bundle of insulated flexible pipes 79 which can be connected to the loading / unloading pipelines 73. The orientable mobile arm 74 adapts to all sizes of LNG carriers. A connecting pipe, not shown, extends inside the tower 78. The loading and unloading station 75 allows the loading and unloading of the LNG carrier 70 from or to the onshore installation 77. The latter comprises liquefied gas storage tanks 20 and connecting pipes 81 connected by the underwater pipe 76 to the loading or unloading station 75.The subsea pipeline 76 allows the transfer of liquefied natural gas between the loading or unloading station 75 and the onshore installation 77 over a long distance, for example 5 km, which makes it possible to keep the LNG carrier 70 at a great distance from the coast during loading and unloading operations.

[0113] To generate the pressure necessary for the transfer of the liquefied gas, pumps on board the LNG carrier 70 and / or pumps fitted to the onshore installation 77 and / or pumps fitted to the loading and unloading station 75 are used.

[0114] Although the invention has been described in connection with several particular embodiments, it is obvious that it is in no way limited thereto and that it includes all technical equivalents of the means described as well as their combinations if these fall within the scope of the invention.

[0115] The use of the verb "comprise", "comprise" or "include" and its conjugated forms does not exclude the presence of other elements or other steps than those set out in a claim.

[0116] In the claims, any reference sign in parentheses cannot be interpreted as a limitation of the claim.

Claims

A sealed and thermally insulating tank (20) for storing a fluid, the tank (20) comprising a tank wall (21, 22) intended to be fixed to a supporting structure (10), the tank wall (21, 22) comprising, in a thickness direction (E): a sealed membrane (5) intended to be in contact with the fluid to be stored, the sealed membrane (5) being metallic and having corrugations (26a, 26b) and flat portions (60) located between the corrugations (26a, 26b), and a thermally insulating barrier arranged between the sealed membrane (5) and the supporting structure (10), the thermally insulating barrier comprising a plurality of juxtaposed insulating blocks (9), an insulating block (9) of the thermally insulating barrier comprising: - a polymer foam layer (41), - an internal plate (42) fixed against the polymer foam layer (41) and having an upper surface supporting flat portions planes (60) of the waterproof membrane (5),the internal plate (42) comprising a housing (14), - a metal anchoring support (93) positioned in the housing (14), the metal anchoring support (93) being movable transversely to the thickness direction (E) of the tank wall (21, 22), the metal anchoring support (93) comprising a top portion (932), and a base (931) wider than the top portion (932) and arranged between the top portion (932) and the polymer foam layer (41), the top portion being flat and continuous so as to be able to be welded at any point to a flat portion (60) of the waterproof membrane (5), and - a cover (8, 800) arranged in the housing (14) and fixed to the insulating block (9), comprising a through-hole (881) inside which the top portion (932) is positioned, the cover (8,800) covering the base (931) of the anchoring support so as to hold the metal anchoring support (93) in the housing (14) in the thickness direction (E) of the tank wall (21, 22), an upper surface of the cover (8, 800) flush with the upper surface of the internal plate (42), the flat portion (60) of the waterproof membrane (5) being welded to the top portion (932) of the metal anchoring support (93)., Tank (20) according to claim 1, in which the housing (14) of the internal plate (42) comprises a central portion (13) receiving the base (931) and a counterbore (911) surrounding the central portion (13) and having a shallower depth than the central portion (13), the cover (8) being fixed to the internal plate (42) in the counterbore (911). Tank (20) according to claim 1 or claim 2, in which a lower surface of the cover (800) comprises a counterbore (82) surrounding the through hole (881) and receiving the base (931) of the metal anchoring support (93), a support portion (83) surrounding the counterbore (82) and being fixed to the layer of polymer foam (41) at the bottom of the housing (14). Tank (20) according to any one of claims 1 to 3, in which the anchoring support (93) is hollow. Tank (20) according to any one of claims 1 to 4, wherein the waterproof membrane (5) is a primary waterproof membrane, the thermally insulating barrier is a primary thermally insulating barrier and the insulating blocks (9) are primary insulating blocks, wherein the tank wall (21, 22) comprises a secondary thermally insulating barrier located against the supporting structure (10) and a secondary sealing membrane located between the secondary thermally insulating barrier and the primary thermally insulating barrier. Tank (20) according to any one of claims 1 to 5, wherein a height of the metal anchoring support (93) is such that the top portion (932) of the metal anchoring support (93) is flush with the upper surface of the internal plate (42). Tank (20) according to any one of claims 1 to 6, wherein the insulating block (9) further comprises a thermal protection sheet (92) bonded to the polymer foam layer (41) at the bottom of the housing (14), the base (931) of the anchoring support being positioned on the thermal protection sheet (92). The tank (20) of claim 7, wherein the thermal protection sheet (92) comprises fiberglass. Tank (20) according to any one of claims 1 to 8, in which the cover (8, 800) is fixed by screwing, stapling or gluing. Tank (20) according to any one of claims 1 to 9, in which the metallic anchoring support (93) is located in the vicinity of a through element which passes through the tank wall (21, 22) in the thickness direction (E). Land-based installation (77) for the storage of a liquefied gas comprising a sealed and thermally insulating tank (20) according to any one of claims 1 to 10. Vessel (70) for transporting a cold liquid product, the vessel (70) comprising a double hull (72) and a sealed and thermally insulating tank (20) according to any one of claims 1 to 10 arranged in the double hull (72). A transfer system for a cold liquid product, the system comprising a vessel (70) according to claim 12, insulated pipes (73, 79, 76, 81) arranged to connect the tank (20) of the vessel (70) to a floating or land-based storage facility (77) and a pump for driving a flow of cold liquid product through the insulated pipes (73, 79, 76, 81) from or to the floating or land-based storage facility to or from the tank (20) of the vessel (70). A method of loading or unloading a ship (70), in which a cold liquid product is conveyed through insulated pipes (73, 79, 76, 81) from or to a floating or land-based storage facility (77) to or from the tank (20) of the ship (70) according to claim 12.

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