Wall for a sealed and thermally insulated tank for storing a liquefied gas

Abstract

The invention relates to a wall (10) for a sealed and thermally insulated liquefied gas storage tank, comprising a primary thermally insulating barrier (14) with a plurality of load-bearing elements (30) and a radiative multilayer insulation blanket (47), said blanket being fixed to one of the load-bearing elements by a fastening device (51) comprising a connecting portion fixed to said load-bearing element and a support portion, wherein the connecting portion comprises two portions movable relative to each other between a separation position in which the two portions are separated from each other to allow the load-bearing element to be positioned through the fastening device and a proximity position in which the two portions are brought closer to each other relative to the separation position, so as to be able to immobilize the fastening device on the load-bearing element. Figure for the abstract: 1

Description

Title of the invention: Wall for a sealed and thermally insulated tank for storing a liquefied gas. Technical field

[0001] The invention relates to the field of sealed and thermally insulated tanks. In particular, the invention relates to the field of sealed and thermally insulated tanks for the storage and / or transport of a liquefied gas, such as liquid dihydrogen, which is at approximately -253°C at atmospheric pressure.

[0002] These tanks can be installed on land or on a floating structure. In the case of a floating structure, the tank can be used for transporting liquefied gas or for receiving liquefied gas used as fuel for the propulsion of the floating structure. In the case of an onshore tank or a port storage structure, it can rest on the ground or the seabed and can be partially or completely buried. Technological background

[0003] From document FR3134571, sealed and thermally insulated tanks for storing a liquefied gas, such as liquid dihydrogen.

[0004] This document discloses a wall for such a tank, comprising successively, along a thickness direction, a secondary thermally insulating barrier which rests against a load-bearing structure, a secondary sealing membrane which rests against the secondary thermally insulating barrier, a primary thermally insulating barrier which rests against the secondary sealing membrane and a primary sealing membrane which rests against the primary thermally insulating barrier and is intended to be in contact with the liquefied gas contained in the tank.

[0005] The primary sealing membrane comprises a first series of corrugations having first corrugations parallel to each other and a second series of corrugations having second corrugations parallel to each other and perpendicular to the first corrugations. The primary sealing membrane thus comprises a plurality of flat zones, each defined between two adjacent first corrugations and between two adjacent second corrugations.

[0006] The primary thermally insulating barrier further comprises a plurality of load-bearing elements which are fixed to the secondary thermally insulating barrier and which rise along the thickness direction.

[0007] Each load-bearing element is fixed to an internal plate against which a flat area of ​​the primary sealing membrane is welded in support.

[0008] The primary thermally insulating barrier further comprises a radiative multilayer insulation blanket which has openings through which pass the load-bearing elements and which extends orthogonally to the thickness direction of the wall.

[0009] In this type of tank wall, fixing the multilayer insulation cover to the load-bearing elements is a delicate operation. Summary of the invention

[0010] One idea underlying the invention is to simplify the fixing of the multilayer insulation cover on the load-bearing elements, and to allow its fixing reliably and quickly at a predefined height of the load-bearing element.

[0011] According to one embodiment, the invention provides a wall for a sealed and thermally insulating tank for storing a liquefied gas, the wall comprising successively, along a thickness direction, a secondary thermally insulating barrier which rests against a load-bearing structure, a secondary sealing membrane which rests against the secondary thermally insulating barrier, a primary thermally insulating barrier which rests against the secondary sealing membrane and a primary sealing membrane which rests against the primary thermally insulating barrier and is intended to be in contact with the liquefied gas contained in the tank; the primary thermally insulating barrier comprising a plurality of load-bearing elements which are fixed to the secondary thermally insulating barrier and which rise along the thickness direction, and a radiative multilayer insulation blanket, which has openings through which the load-bearing elements pass and which extends transversely to the thickness direction of the wall, said multilayer insulation blanket being fixed to one of the load-bearing elements by a fixing device comprising a connecting part fixed to said load-bearing element and a support part extending transversely to the thickness direction of the wall, said insulation blanket being fixed to said support part, in which the connecting part of the fastening device comprises two portions movable relative to each other between a separation position in which the two portions are separated from each other to allow the carrier element to be placed through the fastening device so that the fastening device surrounds the carrier element and a proximity position in which the two portions are brought closer to each other relative to the separation position, so as to be able to immobilize the fastening device on the carrier element by tightening the carrier element.

[0012] Thanks to these characteristics, it is possible to fix a fastening device at a precise height on the load-bearing element, and then, in a second step, to fix the multilayer insulation blanket onto the fastening device. The fastening of the This facilitates the application of multi-layer insulation.

[0013] According to one embodiment, the fastening device is immobilized on the carrier element by gluing the fastening device to the carrier element and / or by elastic clamping of the carrier element and / or by axial blocking of the fastening element which rests on at least one stop element of the carrier element extending outward from the carrier element.

[0014] According to one embodiment, said carrier element has a central part of tubular shape and the two portions of the connecting part of the fastening device form in their position of approach a collar whose internal dimensions are equal, within a clearance, to the external dimensions of the central part of the carrier element.

[0015] According to one embodiment, the connecting part and the support part of the fastening device are made of one or more metal plates.

[0016] According to one embodiment, the two portions of the connecting part are linked by at least one rider.

[0017] According to one embodiment, the two portions of the connecting part are linked by at least one hinge.

[0018] According to one embodiment, the two portions of the connecting part belong to a metallic spring wire or a metallic spring blade.

[0019] According to one embodiment, said spring wire or said spring blade forms a single loop or a plurality of loops around the carrier element.

[0020] According to one embodiment, the connecting part of the fastening device elastically clamps the load-bearing element.

[0021] According to one embodiment, the connecting part of the fastening device is glued onto the supporting element.

[0022] According to one embodiment, the connecting part of the fastening device rests on at least one stop element of the carrier element extending outward from a central part of the carrier element.

[0023] According to one embodiment, the connecting part of the fastening device is formed by a spring wire which has folded ends that are nested one inside the other so as to be able to elastically separate from each other.

[0024] According to one embodiment, the support part of the fastening device includes at least one tab extending projecting from the connecting part.

[0025] According to one embodiment, the tongue is formed or attached to said connecting part of the fastening device.

[0026] According to one embodiment, the two portions of the connecting part belong to a metallic spring wire and the tongue is formed by a fold of the wire or the spring blade.

[0027] According to one embodiment, the tongue is formed by folding a metal plate forming one of the two portions of the connecting part.

[0028] According to one embodiment, the tongue is formed by welding a metal plate onto one of the two portions of the connecting part.

[0029] According to one embodiment, the support part of the fastening device includes a fastening element for the multilayer insulation cover adapted to cooperate with a complementary fastening element of the fastening device.

[0030] According to one embodiment, the fixing element of the multilayer insulation cover is an orifice, the complementary fixing element of the fixing device includes a fir tree clip, a pin or a rivet and the multilayer insulation cover has an opening located opposite this orifice through the fixing element which is traversed by the fir tree clip, the pin or the rivet.

[0031] According to one embodiment, the multilayer radiative insulation blanket comprises a stack of a plurality of sheets made of metal or of polymer material coated with a metal and separated from each other by a textile layer.

[0032] According to one embodiment, each pillar is made of a composite material comprising fibers and a matrix.

[0033] According to one embodiment, the primary thermally insulating barrier comprises insulating elements having an open-cell porous structure which are arranged between the radiative multilayer insulation blanket and the secondary sealing membrane.

[0034] According to one embodiment, the primary thermally insulating barrier comprises a gaseous phase at an absolute pressure of less than 1 Pa.

[0035] According to one embodiment, the insulating elements are chosen from glass wool, rock wool, polyester wadding and open-cell polymer foams.

[0036] The invention also provides a sealed and thermally insulating tank integrated into a load-bearing structure, the load-bearing structure comprising a plurality of load-bearing walls, the tank comprising a plurality of tank walls fixed each time on a respective load-bearing wall, including a tank wall as described above.

[0037] The invention also provides a vessel for the transport of a fluid, the vessel comprising a double hull and a tank as described above, disposed in the double hull.

[0038] The invention also provides a transfer system for a liquefied gas, the system comprising a vessel as described above and insulated pipelines arranged to connect the tank installed in the hull of the vessel to a floating or land-based storage facility.

[0039] The invention also provides a method for loading or unloading a vessel as described above, in which liquefied gas is conveyed through insulated pipelines from or to a floating or land-based storage facility to or from the vessel's tank. Brief description of the figures

[0040] The invention will be better understood, and other objects, details, features and advantages thereof will become more apparent from the following description of several particular embodiments of the invention, given solely by way of illustration and not limitation, with reference to the accompanying drawings.

[0041] Fig. 1 represents a schematic view of a tank wall in cross-section along the wall thickness.

[0042] Figure 2 represents a schematic perspective view of a first mode of realization lisation of the wall fixing device of the [Fig.l], on a load-bearing element.

[0043] Figure 3 represents a schematic flat view of a portion of the device fixing of the [Fig.2].

[0044] Figure 4 represents a schematic perspective view of a second mode of implementation of the wall fixing device of [Fig.1], on a load-bearing element.

[0045] Figure 5 represents a schematic rear perspective view of a third method of embodiment of the wall fixing device of [Fig.l].

[0046] Figure 6 represents a schematic perspective view of a fourth mode of construction of the wall fixing device of [Fig.l].

[0047] Figure 7 shows a schematic top view of the fastening device wall of the [Fig.l].

[0048] Figure 8 represents a schematic perspective view of a fifth mode of construction of the wall fixing device of [Fig.l].

[0049] Figure 9 represents a schematic front view of the fifth embodiment of the wall fixing device of [Fig.1].

[0050] Fig. 10 is a schematic cutaway representation of a hy- ship's tank drug store and a loading / unloading terminal for this tank. Description of the implementation methods

[0051] By convention, the terms "external" and "internal" are used to define the relative position of one element with respect to another, by reference to the inside and outside of the tank. Identical or corresponding elements shown in these figures will be referenced by identical symbols and will not be described each time.

[0052] The liquefied gas intended to be stored in the tank may in particular be liquid hydrogen which has the particularity of being stored at about -253°C at atmospheric pressure.

[0053] The attached figures show different embodiments of a sealed and thermally insulating tank wall.

[0054] This sealed and thermally insulating tank is intended for the storage of a liquefied gas and is intended to be fixed on a supporting structure 1 ([Fig.1]).

[0055] The load-bearing structure 1 may, in particular, be formed of self-supporting metal sheets or, more generally, of any type of rigid partition having suitable mechanical properties. The load-bearing structure is, for example, formed by the double hull of a ship.

[0056] The load-bearing structure 1 has a general polyhedral shape.

[0057] Figure 1 represents a wall 10 of a sealed and thermally insulating tank according to a first embodiment. The wall 10 has a multilayer structure. It comprises successively, along a thickness D direction of the wall 10, from the outside to the inside, a secondary thermally insulating barrier 12, a secondary sealing membrane 13, a primary thermally insulating barrier 14 and a primary sealing membrane 15 intended to be in contact with the liquefied gas contained in the tank.

[0058] The secondary thermally insulating barrier 12 rests against the load-bearing structure 1. It comprises a plurality of insulating panels 16 anchored to the load-bearing structure 1. Each of the insulating panels 16 comprises a layer of insulating polymer foam 17 sandwiched between an inner plate 18 and an outer plate 19. The inner plate 18 and outer plate 19 are, for example, plywood panels bonded to said layer of insulating polymer foam 17. In one embodiment, the inner plate 18 and outer plate 19 are made of a fiber-reinforced polymer matrix, such as glass fibers. The insulating polymer foam may, in particular, be a polyurethane-based foam. The polymer foam is advantageously reinforced with fibers, such as glass fibers, which helps to reduce its thermal contraction.

[0059] The insulating panels 16 are anchored to the supporting structure 1 by means of secondary anchoring devices, not shown. Each insulating panel 16 is, for example, fixed at least at each of its four corners.

[0060] According to one embodiment, the outer plate 19 of the insulating panels 16 protrudes beyond the insulating polymer foam layer 17, at least at the corners of the insulating panel 16, so as to form the support areas of the insulating panels 16 cooperating with the support members of the secondary anchoring devices.

[0061] Portions of sealant 20 are interposed between the outer plate 19 of the insulating panels 16 and the supporting structure 1. The sealant portions 20 thus help to compensate for surface irregularities in the supporting structure 1. According to an advantageous embodiment, the sealant portions 20 adhere to the outer plate 19 of the insulating panels 16 and to the supporting structure 1. The sealant portions 20 participate thus to the anchoring of the insulating panels 16 on the load-bearing structure 1. In such an embodiment, the secondary anchoring devices are optional.

[0062] The insulating panels 16 are substantially rectangular in shape and are placed side by side in parallel rows, separated from each other by gaps ensuring a functional mounting clearance. The gaps are filled with thermal insulation, not shown, such as glass wool, rock wool, or open-cell flexible polymer foam, for example. The gaps may also be filled with insulating plugs, as described in applications WO2019155157 or WO2021028624, for example.

[0063] In the embodiment shown, the inner face of the insulating panels 16 has two sets of grooves 22 perpendicular to each other and designed to receive corrugations 24, projecting outwards from the tank, formed on corrugated metal sheets 25 of the secondary sealing membrane 13 (described in more detail below). Each set of grooves 22 is parallel to two opposite sides of the insulating panels 16. In the embodiment shown, the grooves 22 pass completely through the thickness of the inner plate 10 as well as through an inner portion of the insulating polymer foam layer 17. Advantageously, the grooves 22 have a shape complementary to that of the corrugations 24 of the secondary sealing membrane 13.

[0064] Furthermore, the inner plate 18 of the insulating panels 16 is equipped with metal plates (not visible in the figures) for anchoring the edges of the corrugated metal sheets 25 of the secondary sealing membrane 13 to the insulating panels 16. The metal plates extend in two perpendicular directions, each parallel to one of the two opposite sides of the insulating panels 16. The metal plates 26 are fixed to the inner plate 18 of the insulating panels 16 by means of screws, rivets, or staples, for example. The metal plates are placed in recesses formed in the inner plate 18 such that the inner surface of the metal plates 26 is flush with the inner surface of the inner plate 18 ([Fig. 1]).

[0065] Furthermore, the insulating panels 16 have relaxation slots 27 which reduce their stiffness so that the secondary thermally insulating barrier 12 deforms as homogeneously as possible. This results in the most uniform deformations possible of the corrugations 24 of the secondary sealing membrane 13. Advantageously, the insulating panels 16 have relaxation slots 27 at least opposite each of the corrugations 24 of the secondary sealing membrane 13. Thus, as illustrated for example in [Fig. 1], a relaxation slot 27 extends from the bottom of each of the grooves 22 towards the outer plate 19 of the insulating panels 16. In addition, the insulating blocks 16 also have additional relaxation slots 28 which open onto the outer face of the insulating panels 16 which rests on the outer plate 18. The additional relaxation slots are arranged halfway between two parallel undulations 24, that is to say halfway between two relaxation slots 27 ([Fig. 1]).

[0066] The secondary sealing membrane 13 rests against the secondary thermally insulating barrier 12. It comprises a plurality of corrugated metal sheets 25, each having a substantially rectangular shape. The corrugated metal sheets 25 are, for example, made of Invar®: that is, an iron-nickel alloy whose coefficient of thermal expansion is typically between 1.2 x 10⁶ and 2 x 10⁶ K⁻¹, or of a high-manganese iron alloy whose coefficient of thermal expansion is typically around 7 x 10⁶ K⁻¹. Alternatively, the corrugated metal sheets 25 can also be made of stainless steel or aluminum.

[0067] The corrugated metal sheets 25 are welded overlapping along their edges to ensure the watertightness of the secondary waterproofing membrane 13. Furthermore, the corrugated metal sheets 25 are staggered relative to the insulating panels 16 of the secondary thermal insulation barrier 12 such that each of said corrugated metal sheets 25 extends simultaneously over several adjacent insulating panels 16. To anchor the secondary waterproofing membrane 13 to the secondary thermal insulation barrier 12, the edges of the corrugated metal sheets 25 are welded to the metal plates 26, for example by spot welding.

[0068] The secondary sealing membrane 13 has corrugations 24 and more particularly a first series of corrugations extending parallel to a first direction and a second series of corrugations extending parallel to a second direction. The directions of the series of corrugations are perpendicular to each other. Each series of corrugations is parallel to two opposite edges of the corrugated metal sheet 25. The corrugations 24 here project outwards from the tank, i.e. in the direction of the supporting structure 1. The secondary sealing membrane 13 has, between the corrugations 24, a plurality of flat areas 28 ( [Fig. 1]).

[0069] As shown in [Fig.1], the corrugations 24 of the corrugated metal sheets 25 are housed in the grooves 22 provided in the inner face of the insulating panels 16. They can also be housed in the gaps provided between the adjacent insulating panels 16.

[0070] Furthermore, the flat areas 28 of the secondary sealing membrane 13 are each traversed by a primary anchoring device intended to ensure the anchoring of the load-bearing elements 30 of the primary thermally insulating barrier 14 on the insulating panels 16 of the secondary thermally insulating barrier 12. Each primary anchoring device includes a stud (not visible in [Fig.1]) which passes through the secondary waterproofing membrane 13, the external end of which is fixed to one of the insulating panels 16. The stud has a collar extending radially with respect to the axis of the stud and welded in a watertight manner to the secondary waterproofing membrane 13 around the orifice of said secondary waterproofing membrane 13 through which the stud passes in order to maintain the watertightness of the secondary waterproofing membrane 13.

[0071] Furthermore, an external plate 34, illustrated in [Fig. 1], has an opening through which the stud passes. The primary anchoring device includes a nut that is screwed onto a threaded inner end of the stud, thus securing the external plate 34 against the flat area 28 opposite the secondary sealing membrane 13. The external plates 34 have a dual function. On the one hand, they allow the secondary sealing membrane 13 to be pressed against the insulating panels 16 of the secondary thermally insulating barrier 12, in order to prevent it from being torn away due to overpressure of the secondary thermally insulating barrier 12 relative to the primary thermally insulating barrier 14. On the other hand, they allow the load-bearing elements 30 of the primary thermally insulating barrier 14 to be fixed, which will be described in detail below.

[0072] The external plates 34 are advantageously in contact against the corresponding flat area 28 over more than 70% of the surface of said flat area 28 and advantageously between 90 and 100% of its surface.

[0073] The external plates 34 are, for example, made of metal, such as stainless steel, but can also be made of a composite material, such as an epoxy resin loaded with glass fibers, for example.

[0074] The primary thermally insulating barrier 14 rests against the secondary sealing membrane 13.

[0075] It comprises a plurality of load-bearing elements 30 extending along the thickness direction D of the wall 10. The load-bearing elements 30 support the primary sealing membrane 15 and, consequently, resist the forces due to hydrostatic and dynamic pressures exerted on the primary sealing membrane 15 by the liquefied gas contained inside the tank. The load-bearing elements 30 are aligned in rows parallel to the direction of the corrugations of the first series of corrugations and in rows parallel to the direction of the corrugations of the second series of corrugations.

[0076] The load-bearing elements 30 each comprise an outer base 36, an inner base 37, and a pillar 38 extending between the outer base 36 and the inner base 37. The outer base 36 and the inner base 37 each have a sleeve 39 in which is received by fitting one end of the pillar 38 and a support flange 40 which extends radially from one end of the sleeve 39 orthogonally to it. In an alternative embodiment, the sleeves of the outer base and the inner base are received by fitting inside the pillars.

[0077] The outer base 36 and the inner base 37 can be made of metal, such as stainless steel, or of a composite material, such as a glass fiber-reinforced epoxy resin, for example. The outer base 36 and the inner base 37 can be fixed to the pillar 38 by any means, and in particular by bonding.

[0078] According to another embodiment, the pillar as well as the external base and the internal base are formed in one piece, for example by molding.

[0079] The pillars 38 have a tubular shape, preferably with a circular cross-section. They extend in a direction parallel to the thickness direction D of the wall. In an advantageous embodiment, the pillars 38 are made of a composite material comprising fibers and a matrix. Such pillars 38 make it possible to obtain satisfactory compressive strength for a limited conductive cross-section, which limits heat conduction from the outside to the inside of the tank through the pillars 38. The fibers are, for example, selected from glass fibers, carbon fibers, aramid fibers, flax fibers, basalt fibers, and mixtures thereof.The matrix is, for example, chosen from polyethylene, polypropylene, poly(ethylene terephthalate), polyamide, polyoxymethylene, polyetherimide, polyacrylate, polyaryl ether ketone, polyetherether ketone, copolymers thereof, polyester, vinyl ester, epoxy, and polyurethane. According to a particular embodiment, the pillars 38 are made of a glass fiber-reinforced epoxy resin.

[0080] The pillars 38 are advantageously provided with through-holes, not shown, which facilitate the depressurization of their internal space when the primary thermally insulating barrier 14 is depressurized, as described below. Furthermore, the internal space of the pillars 38 is advantageously filled with a gas-permeable insulating packing, particularly one made of an open-cell porous material. The insulating packing is, for example, an open-cell polymer insulating foam, such as open-cell polyurethane foam, glass wool, rock wool, melamine foam, polyester wadding, polymer aerogels, such as polyurethane-based aerogel, notably marketed under the brand name Slentite®, or silica aerogels.

[0081] The support collars 40 of the external bases 36 are each fixed to one of the external plates 34, for example by means of rivets distributed around the axis of the carrier element 30.

[0082] Furthermore, the support flanges 40 of the internal bases 37 are each in support and fixed against an internal plate 42. The internal plates 42 are, for example, made of a metal, such as stainless steel. The support flanges 40 of the internal bases 37 are, for example, fixed to the internal plate 42 by means of rivets distributed around the axis of the supporting element 30.

[0083] The load-bearing elements 30 thus form discrete support structures which are not rigidly connected to each other and which each support a flat area 46 of the primary waterproofing membrane 15 (described later), which allows a good distribution of stresses in the primary waterproofing membrane 15.

[0084] The primary sealing membrane 15 rests against the primary thermally insulating barrier 14 and is intended to be in contact with the liquefied gas contained in the tank.

[0085] It is also obtained by assembling a plurality of corrugated metal sheets. Each of the corrugated metal sheets has a substantially rectangular shape. The corrugated metal sheets are, for example, made of Invar®: that is to say, an iron and nickel alloy whose coefficient of expansion is typically between 1.2 x 10⁶ and 2 x 10⁶ K⁻¹, or of an iron alloy with a high manganese content whose coefficient of expansion is typically around 7 x 10⁶ K⁻¹. Alternatively, the corrugated metal sheets can also be made of stainless steel or aluminum.

[0086] The corrugated metal sheets forming the primary sealing membrane 15 are welded with overlap along their edges to ensure the sealing of the primary sealing membrane 15. The primary sealing membrane 15 has corrugations 45. More particularly, it has a first series of corrugations extending parallel to a first direction and a second series of corrugations extending parallel to a second direction. The directions of the series of corrugations are perpendicular and are parallel or perpendicular to the rows of load-bearing elements 30. Each of the series of corrugations is parallel to two opposite edges of the corrugated metal sheets of the primary sealing membrane 15. The corrugations 45 protrude towards the inside of the tank, i.e. in the opposite direction to the load-bearing structure 1. Each corrugated metal sheet has, between the corrugations 45, a plurality of flat areas 46 ([Fig.1]).

[0087] The pitch of the corrugations 24 of the secondary waterproofing membrane 13 is equal to the pitch of the corrugations 45 of the primary waterproofing membrane 15 or to an integer multiple thereof. Furthermore, each of the corrugations 24 of the secondary waterproofing membrane 13 is arranged opposite, along the thickness direction of the wall 11, a corrugation 45 of the primary waterproofing membrane 15 ([Fig. 1]). Thus, each flat area 46 of the primary waterproofing membrane 15 is located opposite, along the thickness direction D of the wall 11, a flat area 28 of the secondary waterproofing membrane 13. From then, the axis of each load-bearing element 30 passes both through the center of a flat area 46 of the primary waterproofing membrane 15 and through the center of a flat area 28 of the secondary waterproofing membrane 13.

[0088] Advantageously, the internal plates 42 are each in contact against the corresponding flat area 46 of the primary sealing membrane 15 over more than 70% of the surface of said flat area 46 and advantageously between 90 and 100% of its surface.

[0089] The corrugated metal sheets of the primary sealing membrane 15 are at least anchored, by welding, along their edges on the internal plates 42. To do this, the edges of the corrugated metal sheets are welded to the internal plates 42, for example by spot welds.

[0090] According to an advantageous embodiment, the corrugated metal sheets are also anchored to the internal plates 42 outside their edge areas. For this purpose, the corrugated metal sheets can, in particular, be welded to the internal plates 42 by through-welding. According to an advantageous embodiment, the corrugated metal sheets are welded to each of the internal plates 42 that support them. Such an embodiment is particularly advantageous in that it allows for an even more uniform distribution of stresses between the corrugations 45 of the primary sealing membrane 15.

[0091] Furthermore, the primary thermally insulating barrier 14 has a gaseous phase that is under negative pressure, i.e., has an absolute pressure lower than atmospheric pressure, in order to give the primary thermally insulating barrier 14 the required thermally insulating properties. The gaseous phase of the primary thermally insulating barrier 14 is advantageously placed at an absolute pressure less than 1 Pa, advantageously less than 10¹ Pa, preferably less than 10² Pa, and for example, on the order of 10³ Pa. To achieve this, the primary thermally insulating barrier 14 is advantageously connected to a vacuum pump.

[0092] According to an advantageous embodiment, a cryopumping phenomenon is used, as an alternative or complement to the aforementioned vacuum pump, to obtain the target vacuum level in the primary thermally insulating barrier 14. Prior to being depressurized, the primary thermally insulating barrier 14 is charged with an inert gas having a solid condensation temperature higher than the liquefaction temperature of the liquefied gas stored in the tank. For example, when the liquefied gas stored in the tank is liquid hydrogen, the inert gas can be carbon dioxide. Thus, given the temperature of hydrogen in its liquid state, the carbon dioxide contained in the primary thermally insulating barrier 14 condenses into a solid state within the barrier, thereby reducing the pressure therein.

[0093] In addition to being depressurized, the primary thermally insulating barrier 14 includes insulating materials to further enhance its insulating properties. Also, as shown in [Fig. 1], the primary thermally insulating barrier 14 further includes a radiative multi-layer insulation blanket 47 that reduces heat transfer by thermal radiation. The radiative multi-layer insulation blanket 47 is typically made of a material designated by the acronym MLI for "multi-layer insulation."

[0094] Thus, the radiative multilayer insulation blanket 47 comprises a stack of a plurality of sheets made either of metal, such as aluminum or silver, for example, or of a metal-coated polymer material, said sheets being separated from one another by a textile layer made of polymer fibers, such as polyester fibers, or glass fibers. The plastic sheets are, for example, made of polyimide, notably marketed under the brand name Kapton®, or of poly(ethylene terephthalate), notably marketed under the brand name Mylar®. These thin sheets are coated on each side with a metal, such as aluminum or silver. In the description of the invention, although not mentioned thereafter, the radiative multilayer insulation blanket 47 may further comprise an additional thermal protection layer made of resistant materials such as glass fibers.Such a layer helps to protect the cover 47 against external aggressions, for example thermal projections due to the welds of the membrane near the cover 47.

[0095] As illustrated in Figures 1 and 8, the radiative multilayer insulation blanket 47 has openings 47A (visible in [Fig.8]) through which the pillars 38 of the load-bearing elements 30 pass. The radiative insulation blanket 47 extends transversely to the thickness direction D of the wall 10, i.e. inclined with respect to the thickness direction D.

[0096] Advantageously, the radiative multilayer insulation blanket 47 is positioned in the coldest part of the primary thermally insulating barrier 14. In other words, the radiative multilayer insulation blanket 47 is positioned in a plane that is parallel to the secondary 13 and primary 15 sealing membranes but closer to the primary 15 sealing membrane than to the secondary 13 sealing membrane. This increases the efficiency of the radiative multilayer insulation blanket 47 because it is positioned in the coldest area of ​​the primary thermally insulating barrier 14, thus reducing the emissivity of each of its layers. However, it is also possible to position the radiative multilayer insulation blanket 47 in a plane parallel to the sealing membranes, closer to the membrane secondary sealing to ensure good roof efficiency.

[0097] The multilayer radiative insulation cover 47 is fixed to at least one of the load-bearing elements 30 by a fixing device 51; 52; 53; 54; 55, comprising a connecting part 511; 521; 531; 541; 551 fixed to said load-bearing element 30 and a support part 512; 522; 532; 542; 552 extending transversely to the thickness direction D of the wall 10.

[0098] The insulation cover 47 is fixed to said support part 512; 522; 532; 542; 552. More specifically, the insulation cover 47 is fixed directly to said support part 512; 522; 532; 542; 552. It is in contact with the fixing device at the level of its support part.

[0099] The connecting portion 511; 521; 531; 541; 551 of the fastening device 51; 52; 53; 54; 55 comprises two portions 51 IA, 511B; 521 A, 521B; 531 A, 53 IB; 541A; 551A, 551B movable relative to each other between a separation position in which the two portions are separated from each other to allow the placement of the carrier element 30 through the fastening device 51; 52; 53; 54; 55 such that the fastening device 51; 52; 53; 54; 55 surrounds the carrier element 30, and a position of approach in which the two portions are brought closer together relative to the position of separation, so as to be able to immobilize the fixing device 51; 52; 53; 54; 55 on the carrier element 30 by tightening on the carrier element.

[0100] The fastening device in the position of bringing the two portions together is therefore adapted to clamp the load-bearing element.

[0101] The fixing device 51; 52; 53; 54; 55 is more particularly immobilized on the carrier element 30 by gluing the fixing device 51; 52; 53; 54; 55 on the carrier element 30 and / or by elastic clamping of the carrier element 30 and / or by axial blocking along the carrier element by bearing on a stop element protruding from the carrier element.

[0102] The supporting element 30 has a central portion located between the external 36 and internal 37 bases of the supporting element 30, which belongs to the pillar 38. The two portions of the connecting part 511; 521; 531; 541; 551 of the fastening device, in their close-coupled position, form a collar whose internal dimensions are equal, within a certain clearance, to the external dimensions of the central portion of the supporting element 30. By way of non-limiting example, for an external diameter of the central portion of the supporting element of 62.5 mm, this clearance can be between 0 and 3 mm, preferably between 0 and 2 mm. This clearance corresponds to the thickness of the adhesive between the supporting element and the connecting part (a clearance of 0 mm corresponding to a so-called clamping position in which the connecting device is fixed and clamped against the supporting element). Advantageously, the clearance is between 100 and 200 pm (micrometers).

[0103] This collar has a main axis X which extends along the direction of the pillar 38, that is to say along the thickness direction D of the wall.

[0104] The support portion 512; 522; 532; 542; 552 of the fastening device includes at least one tab 512A; 522A; 532A; 542A; 552A extending outward from the connecting portion.

[0105] This tab is formed or attached to said connecting part of the fastening device.

[0106] According to the first, second and third embodiments of the wall 10, the connecting part 511; 521; 531 and the support part 512; 522; 532 of the fixing device 51, 52, 53 are made by one or more metal plates, as shown in figures 2 to 5.

[0107] In these embodiments, each portion of the connecting part 511; 521; 531 is made by a metal plate 513; 523; 533 of elongated shape along a longitudinal axis L ([Fig.3]) which is shaped to fit the contour of the central part of the supporting element 30. The central part of the supporting element corresponds here to an area of ​​the pillar 38 located between the external base 36 and the internal base 37 of the supporting element 38. The plate 513; 523; 533 has a generally rectangular shape before shaping, delimited by two parallel longitudinal edges Cl, C2 connected by two longitudinal end edges C3, C4 ([Fig.3]).

[0108] The pillar 38 having here a cylindrical shape, each portion of the connecting part 511; 521; 531 is curved so as to form a cylindrical half-sleeve with main axis X.

[0109] The support portion 512; 522; 532 of the fixing device 51; 52; 53 comprises a plurality of plates forming the tabs 512A; 522A; 532A. Preferably, an even number of plates are arranged so as to be diametrically opposed around the pillar 38 when the fixing device is installed around the pillar.

[0110] These plates can come from formation with the plate 513; 523 constituting each portion 511A; 521A of the connecting part, as is the case in the first and second embodiments of figures 2, 3 and 4.

[0111] In this case, each plate 512A; 522A extends from the same longitudinal edge of the plate 513, 523 and is folded with respect to the plate 513; 523 so as to extend in a plane transverse to the principal axis X of the connecting part.

[0112] This transverse plane is orthogonal to the principal axis X of the connecting part of the fastening device. Alternatively, the transverse plane could be inclined at a non-zero angle other than 90°.

[0113] When the fastening device is in place around the supporting element, the main axis X of the connecting part 511; 521; 531; 541; 551 of the fastening device is parallel to the thickness direction D of the wall, along which the load-bearing elements 30 are raised.

[0114] The plate 513; 523 is preferably curved, providing a flat 514; 524 corresponding to each plate 512A; 522A (figures 2 and 4), so as to facilitate folding of the latter and limit stresses.

[0115] Figure 3 shows one of the portions of the connecting part in its flat state, before it is formed. The plates and the insert are formed by cutting from a single flat sheet. Reference numbers 512P and 513P designate, respectively, the plates and the insert of the portion of the connecting part before the sheet is formed. The sheet has, for example, a thickness of 1 millimeter.

[0116] Each plate 532A can also be attached to the metal plate 533 constituting each portion of the connecting part 531, as in the third embodiment shown in [Fig.5].

[0117] The plates 532A forming the support portion 532 of the fastening device 53 according to the third embodiment shown in [Fig. 5] are welded here to the plate 533 forming the connecting portion after the latter has been bent. No flat is then provided in the plate 533 of the connecting portion.

[0118] In the first, second and third embodiments of figures 2 to 5, the ends of each portion of the connecting part constitute attachment ends allowing the two portions of the connecting part to be joined together.

[0119] In the first embodiment of [Fig.2], the two portions 51 IA, 51 IB of the connecting part 511 are linked by at least one hinge.

[0120] The attachment ends of each portion 511 A, 51 IB of the connecting part 511 form at least one hinge. Here, the attachment ends form two hinges.

[0121] One of the attachment ends comprises a central tongue 516 extending along the longitudinal axis of the plate 513 and delimited by two lateral notches 516A formed in the longitudinal edges of the plate 513 to one of the longitudinal end edges of this plate 513. The other attachment end comprises two lateral tongues 515 extending along the longitudinal axis L of the plate 513 and delimited by a central notch 515A formed in the longitudinal end edge of the plate 513.

[0122] The lateral notches 516A and central notches 515A are complementary to each other.

[0123] Figure 3 shows the notches and tongues 515P, 516P as cut into the sheet metal forming the pads 512A and the plate 513, when this sheet metal is still flat. The unformed pads and plate are referenced as 512P and 513P respectively in this figure.

[0124] Each central tongue 516 and lateral tongue 515 is curved outwards from the half- A sleeve formed by the portion of the connecting part is designed to create a housing 515B, 516B—also called a "hinge"—for the hinge, adapted to receive a pin 519 that forms the axis of rotation of the hinge. Each of these housings 515B, 516B extends in a direction parallel to the principal axis X of the cylindrical half-sleeve formed by each portion 51IA, 51IB of the connecting part 511. The central tongue 516 of one of the portions 511A, 51IB of the connecting part 511 is received between the lateral tongues 515, in the central notch 516A of the other portion 511B, 511A of the connecting part 511, so as to align the housings 515B, 516B formed by the central and lateral tongues.

[0125] Advantageously, the housing 516B formed by the central tongue 516A of the plate 513 has an oblong shape, elongated along the longitudinal axis L of the plate 513 ([Fig. 2]). The central tongue 516A of one portion of the connecting part can also slide into the central notch 515A of the other portion. Thus, the relative position of the two portions of the connecting part can be adjusted. The internal dimensions of the connecting part 511 of the fastener can also be adjusted in this way.

[0126] Attachment ends forming hinges, similar to those described above, are also provided in the third embodiment, as seen in [Fig.5].

[0127] In the second embodiment, the two portions of the connecting part are joined by at least one bracket. This bracket 529 has a U-shape with a base from which two lateral arms extend. In the example shown in [Fig. 4], two brackets 529 are used to assemble the two portions of the connecting part of the fastener 52.

[0128] As shown in [Fig.4], each longitudinal end 524A, 524B of each portion 521A, 521B of the connecting part 521 is here bent outwards from the half-sleeve formed by the portion 521A, 521B of the connecting part so as to form a housing 525A, 525B extending along the main axis X of the cylindrical half-sleeve formed by each portion of the connecting part and adapted to accommodate one of the two lateral arms of the rider 529.

[0129] The rider 529 is made of metal wire and preferably has elasticity allowing elastic separation of the two arms inserted into the housings for the two portions 521A, 521B of the connecting part 521 of the fixing element 52. This elasticity is here conferred by an elbow 529A formed in the base of the U formed by the rider 529.

[0130] Each leg of the jumper 529 passes through the housings 525A, 525B of each portion 521A, 521B. One free end of one of the legs of the jumper 529 is bent outwards from the housing so that the jumper 529 cannot be removed from the housing of one of the portions of the connecting part. The free end of the other branch is straight and can slide freely into the housing of the other portion. It is anticipated that one of the two 529 brackets will be connected to each portion in this way.

[0131] Preferably, as shown in [Fig.4], one of the two riders 529 is inserted into the receiving slots 525A, 525B of the two portions 521A, 521B so that its base is oriented towards the primary membrane 15 and the other rider is inserted into the receiving slots 525A, 525B of the two portions 521A, 521B so that its base is oriented towards the secondary membrane 13.

[0132] The connecting part 511; 521; 531 of the fastening device 51; 52; 53 is fixed to the carrier element 30 for example by gluing.

[0133] Alternatively, the connecting portion of the fastening device can be immobilized on the load-bearing element by bearing on at least one stop element of the load-bearing element extending beyond the central portion of the load-bearing element. The connecting portion of the fastening device then rests on the stop element. The axial movement of the fastening device outwards from the wall is limited by the stop element. One or more additional stop elements can be added on the other side of the fastening device, towards the inside of the wall, to prevent any axial movement of the fastening device along the pillar. The connecting portion of the fastening device can also be bonded around the load-bearing element.

[0134] The two portions 51 IA, 511B; 521 A, 521B; 531 A, 53 IB of the connecting part are movable relative to each other, either by pivoting thanks to the hinge or the bracket, or because they can be separated from each other, either thanks to the elastic properties of the bracket, or by translation within the oblong-shaped housing 516B formed by the central tongue 516A of each portion. They are separated from each other and placed in a spread position to allow the carrier element to be inserted through the fastening device so that the fastening device surrounds the carrier element.

[0135] For this purpose, the two portions may be entirely or partially separated from each other or not.

[0136] Preferably, the two portions remain attached by two of the attachment ends, while the cooperation between the other two attachment ends is broken. One of the hinges or one of the brackets remains in cooperation with the two portions of the connecting part. The pin of the other hinge is removed to release the two portions, or the right arm of the other bracket is removed from its housing. The position of the two portions of the connecting part apart then corresponds to an open configuration of the fastening device. The two portions are pivoted relative to each other and separated so that the pillar 38 can pass laterally- The relative movement of the pillar and the fixing device is transverse to the thickness direction of the wall.

[0137] When the fastening device 51; 52; 53 is positioned at the desired height along the load-bearing element 30, the connecting portions of the fastening device are then closed around the pillar and the cooperation of the other fastening ends is restored. The connecting portions are then in their closed position.

[0138] This is particularly useful when the carrier element 30 already has its internal base 39 at the time the fixing device 51; 52; 53 is installed.

[0139] In some cases, the fastening device can be threaded onto the pillar 38 without breaking the cooperation of the attachment ends of the two portions of the connecting part of the fastening device, for example when the fastening device is installed before the internal base 39 is fixed onto the end of the pillar 38. Then, the two portions of the connecting part can be separated, either, in the first and third embodiments, by sliding the pin 519 into the oblong-shaped receiving housing 516B formed by the central tongue 516A, or, in the second embodiment, by elastically deforming the jumper 529. The fastening device remains in a closed configuration.

[0140] The fixing device 52 is then slid along the pillar 38. The placement of the fixing device 52 around the load-bearing element then implies an axial movement of the fixing device, along the thickness direction D of the wall.

[0141] When the fastening device 51; 52; 53 is located at the desired height along the carrier element 30, the portions of the connecting part are brought together in their closed position so as to be able to immobilize the fastening device on the carrier element.

[0142] The fastening device is immobilized on the carrier element by gluing the fastening device to the carrier element and / or by elastic clamping of the carrier element and / or by bearing on at least one stop element of the carrier element extending outward from the central part of the carrier element.

[0143] A layer of glue is applied between the connecting part and the pillar.

[0144] In the case of the first embodiment, a temporary holding device can be used to tighten the fixing device around the pillar while the glue sets.

[0145] This temporary retaining device may, for example, include a removable plastic collar. It clamps the fixing device against the pillar while the adhesive sets.

[0146] In the case of the second embodiment, the internal dimensions of the connecting part of the fastening device are determined such that this connecting part tighten the pillar in the resting position of the riders 529. This tightening is sufficient to keep the fixing device 52 in place while the glue sets.

[0147] According to other embodiments, the connecting part 541; 551 and the support part 542; 552 of the fastening device 54; 55 belong to a metal spring wire or a metal spring blade.

[0148] For example, according to the fourth and fifth embodiments of the wall 10, the connecting part 541; 551 and the supporting part 542; 552 of the fastening device 54; 55 belong to a metallic spring wire 540, 550.

[0149] In these embodiments, the two portions 541 A, 541B; 551 A, 55 IB of the connecting part 541; 551 are made by a single spring wire which is shaped to follow the contour of the central part of the supporting element 30. The central part of the supporting element corresponds to the area of ​​the pillar 38 located between the external base 36 and the internal base 37 of the supporting element 38.

[0150] The pillar 38 having here a cylindrical shape, the spring wire is wound so as to form a single turn or a plurality of turns with principal axis X around the supporting element 30.

[0151] Thanks to the elastic deformation properties of the spring wire or spring blade, it is possible to separate the two ends of the spring wire or spring blade in order to increase the internal dimensions of the connecting part of the fastening device thus formed, as shown schematically in [Fig.7]: by bringing together the loops Bl and B2 located at the ends of the spring wire, the parts of the spring wire adjacent to these loops move apart and the turns deform in such a way as to present a larger diameter.

[0152] In the fourth embodiment of Figures 6 and 7, the spring wire forms 3.25 turns, while in the fifth embodiment of [Fig.8], the spring wire forms a single turn.

[0153] The support portion 542; 552 of the fastening device 54; 55 comprises a plurality of folds of the spring wire forming the tabs 542A; 552A. Preferably, an even number of folds are provided, arranged so as to be diametrically opposed around the pillar 38 when the fastening device is installed around the pillar.

[0154] The folds forming the tabs 542A; 552A extend from the part of the spring wire forming the coil closest to the primary membrane 15.

[0155] The folds forming the tabs may include loops or undulations of the spring wire. In the example of the fourth embodiment, four tabs are provided, formed by two loops B1, B2 and two undulations B3, B4. The loops B1, B2 are closed upon themselves while the undulations are open.

[0156] These folds extend in a plane transverse to the principal axis X of the connecting part. This transverse plane is orthogonal to the principal axis X.

[0157] In the fifth embodiment, the two ends of the spring wire are folded towards the secondary membrane: one forms a hook 553 and the other forms a hooking element 554 which cooperates with the hook to hold together the two ends of the spring wire.

[0158] The hook 553 and the attachment element 554 extend parallel to the principal axis X. They are nested within each other so that they can elastically separate. The attachment element can navigate within the hook 553 so that the two ends of the spring wire can move apart under stress and then come together when the spring wire returns to its resting shape.

[0159] In embodiments in which the fastening device is formed by a spring wire or a spring blade, the connecting part 541; 551 of the fastening device 54; 55 elastically clamps the carrier element 30. For this purpose, the internal dimensions of the connecting part at rest are determined to be slightly smaller than the external dimensions of the central part of the carrier element around which the fastening device is installed.

[0160] It is also possible to provide that the spring wire or spring blade is glued onto the carrier element 30.

[0161] In the latter case, the bonding is carried out in addition to, or instead of, the elastic clamping. When bonding replaces the elastic clamping, the internal dimensions of the connecting part can be equal, within a clearance allowing the adhesive to be applied, to the external dimensions of the supporting element.

[0162] When gluing is carried out in addition to elastic clamping, partial or spot gluing of the connecting part may be provided for.

[0163] In particular, in the fifth embodiment shown in [Fig.8], a plurality of additional folds of the spring wire constituting the fastening device are provided, oriented towards the secondary membrane and extending parallel to the main axis X.

[0164] The additional folds are evenly distributed around the circumference of the connecting portion. There are three of them here. A drop of glue is placed at the end of each additional fold. This localized gluing on a portion of the spring wire, the length of which is very short compared to its total length in contact with the carrier element 30, allows the elastic properties to be maintained and ensures the attachment of the connecting portion to the carrier element 30 in the event of thermal contraction of the latter, without increasing the clamping force on the carrier element by the fastening device.

[0165] The scope of the invention remains unchanged if the two portions 541A, 541B; 551A, 55IB of the connecting part 541; 551 are formed by a single aluminum blade shaped to conform to the contour of the central part of the supporting element 30. Such a blade takes the form of a monolithic bracelet, by An example made of 1000 series aluminum alloy (containing 99% or more aluminum) suitable for deformation during its placement around the carrier element 30. This bracelet has the required ductility to allow its deformation. Once positioned around the carrier element, the bracelet can be closed with a clip, in a manner similar to that described previously.

[0166] As an alternative or in addition to the fixing by gluing or clamping described above for the first, second, third, fourth and fifth embodiments, the connecting part of the fixing device rests on at least one stop element of the carrier element extending outward from a central part of the carrier element.

[0167] The pillar may for this purpose include a plurality of bosses, for example diametrically opposed, on which rests the connecting part of the fixing device.

[0168] The support part 512; 522; 532; 542; 552 of the fixing device 51; 52; 53; 54; 55 includes a fixing element 518; 528; 538; 548; 558 of the multilayer insulation cover adapted to cooperate with a complementary fixing element 560 of the fixing device.

[0169] In the embodiments shown in the attached figures, the fixing element 518; 528; 538; 548; 558 of the support part 512; 522; 532; 542; 552 is a through hole.

[0170] The additional fastening element 560 is, for example, a fir tree clip as shown in Figures 8 and 9. This fir tree clip comprises a head and a body with retaining pins.

[0171] The multilayer insulation cover 47 has an opening 48 located opposite each through hole of the fixing element ([Fig.8]).

[0172] The body of the fir staple 560 passed through this opening 48 of the multilayer insulation cover 47 and through the through hole forming the corresponding fixing element 518; 528; 538; 548; 558 of the fixing device 51; 52; 53; 54; 55.

[0173] Alternatively, the additional fastening element of the fastening device can also be a pin or a rivet.

[0174] Alternatively, the additional fastening element of the fastening device may also include a first part of a hook and loop fastener of the velvet or hook type and the multi-layer insulation cover may then include the second additional part of the hook and loop fastener, of the hook or velvet type, respectively.

[0175] After the fastening device 51; 52; 53; 54; 55 has been installed on the support element 30, the multilayer insulation blanket 47 is slipped onto the support element 30 by passing it through an opening 47A in the blanket of multilayer insulation. This opening 47A has a contour adapted to a near-close external contour of the pillar 38 surrounded by the multilayer insulation cover 47. The opening 47 can be extended by radial slots 47B, for example 4 in number, which facilitate the passage of the cover over the pillar 38.

[0176] Fir staples or other additional fasteners are driven through the openings 48 of the multilayer insulation cover 47 and through the through holes in the support part 512; 522; 532; 542; 552, so as to fix the cover onto the fixing device.

[0177] A fixing device 51; 52; 53; 54; 55 is for example provided on all the load-bearing elements 30 of the primary thermally insulating barrier 14.

[0178] Alternatively, a fixing device is attached to a number of load-bearing elements strictly less than the total number of load-bearing elements of the primary thermally insulating barrier, for example, a fixing device is attached to one out of every two load-bearing elements so that the load-bearing elements having a fixing device and a load-bearing element not having a fixing device, for the same multi-layer insulation coverage, are alternated in the two directions of alignment of the load-bearing elements.

[0179] The primary thermally insulating barrier 14 further comprises insulating elements 49 which have an open-cell porous structure and which are arranged between the radiative multilayer insulation blanket 47 and the secondary sealing membrane 13.

[0180] Such insulating elements 49 have several functions. First, they allow for a further reduction in the temperature of the area of ​​the primary thermally insulating barrier 14 in which the radiative multilayer insulation blanket 47 is positioned, thereby further increasing its efficiency. Second, the insulating elements 49 also help to limit the degradation of thermal insulation performance when the pressure inside the primary thermally insulating barrier 14 exceeds the pressure values ​​prescribed for the use of the radiative multilayer insulation blanket 47 alone.

[0181] Indeed, the aforementioned type of radiative multilayer insulation blankets 47 exhibit excellent thermal insulation performance at low pressure values, typically less than or equal to 103 Pa, but the higher the pressures they are subjected to, the more their performance degrades. Such pressure conditions are particularly likely to occur in the event of a loss of seal in the primary sealing membrane 15 or the secondary sealing membrane 13, degrading the level of negative pressure inside the primary thermally insulating barrier 14, or during the cooling of the tank as long as the inert gas contained in the primary thermally insulating barrier 14 has not been released. fully condensed in a solid state, or when the tank's fill level is low, for example, during a ship's return voyage when the tank contains only a small amount of liquefied gas. The insulating elements 49 also reduce the activation capacity of convective flows within the primary thermally insulating barrier 14. Thirdly, the insulating elements 49 provide surfaces for receiving solids resulting from the solid condensation of the inert gas(s) contained in the primary thermally insulating barrier 14, thus limiting the mechanical stresses that could be exerted on the other elements of the wall 10, and in particular on the load-bearing elements 30, the multi-layer radiative insulation blanket 47, and the secondary 13 and primary 15 sealing membranes.

[0182] The insulating elements 49 are, for example, selected from glass wool, rock wool, polyester wadding, open-cell polymer foams, such as open-cell polyurethane foam, and melamine foams. Advantageously, the insulating elements 49 are made of glass wool. The insulating elements 49 are advantageously supplied in the form of panels with a structural integrity that allows them to be handled easily.

[0183] In the embodiment of [Fig. 1], the insulating elements 49 have a thickness less than the distance, along the thickness direction of the wall 11, between the secondary sealing membrane 13 and the radiative multilayer insulation blanket 47. In other words, a void is present between the insulating elements 49 and the radiative multilayer insulation blanket 47. This makes it possible to reduce the quantity of insulating elements 49 used and thus helps to reduce the costs of the tank without significantly degrading the thermal insulation performance of the primary thermally insulating barrier 14, particularly when the pressure inside the primary thermally insulating barrier 14 is greater than the prescribed pressure value.

[0184] According to another embodiment not shown, the insulating elements can occupy the entire space between the radiative multilayer insulation blanket and the secondary waterproofing membrane. The secondary thermally insulating barrier can then further include one or more retention devices to limit the movement of the insulating elements towards the primary waterproofing membrane, thus preventing them from compressing the radiative multilayer insulation blanket and thereby degrading its performance.

[0185] According to another embodiment, the undulations of the secondary sealing membrane do not protrude outwards, i.e. towards the supporting structure, but inwards, i.e. in a direction opposite to the supporting structure.

[0186] According to another embodiment of the wall of a sealed and thermally insulating tank, the primary sealing membrane has two layers of metal sheets Corrugated sheets overlapped one on top of the other, as described in document FR3134571 with reference to figure number 11 of that document. This ensures redundancy of the sealing function and thus improves the reliability of the primary waterproofing membrane.

[0187] The two layers of corrugated metal sheets each have a structure analogous to that of the primary sealing membrane described above. The corrugations of the two layers are arranged at identical intervals and are positioned opposite each other along the thickness direction of the wall.

[0188] Such membrane tanks can be used for the storage and / or transport of a low-temperature liquid, such as Liquefied Natural Gas (LNG) at approximately -162°C at atmospheric pressure, Liquid Hydrogen (LH2) at -253°C at atmospheric pressure, Ammonia (NH3) at -30°C at atmospheric pressure, or Liquefied Petroleum Gas (also known as LPG), for example, at a temperature between -50°C and 0°C. These tanks can be installed on land or on a floating structure. In the case of a floating structure, the tank can be used for transporting liquefied gas or for receiving liquefied gas to serve as fuel for the propulsion of the floating structure. In the case of an onshore tank or a port storage structure, it can rest on the ground or the seabed and can be partially or completely buried.

[0189] With reference to [Fig. 10], a cutaway view of a vessel 70 shows a sealed and thermally insulating tank 71 of generally prismatic shape mounted in the double hull 72 of the vessel. The wall of the tank 71 comprises a primary sealing membrane intended to be in contact with the liquefied gas, preferably liquid hydrogen, contained in the tank, a secondary sealing membrane arranged between the primary sealing membrane and the double hull 72 of the vessel, and two thermally insulating barriers arranged respectively between the primary sealing membrane and the secondary sealing membrane and between the secondary sealing membrane and the double hull 72.

[0190] In a manner known per se, loading / unloading pipelines 73 arranged on the upper deck of the ship can be connected, by means of suitable connectors, to a marine or port terminal to transfer a cargo of liquefied gas from or to the tank 71.

[0191] Figure 10 also shows an example of a marine terminal comprising a loading and unloading berth 75, a subsea pipeline 76, and an onshore facility 77. The loading and unloading berth 75 is a fixed offshore facility comprising a movable arm 74 and a tower 78 that supports the movable arm 74. The movable arm 74 carries a bundle of insulated flexible pipes 79 that can be connected to the loading / unloading pipelines 73. The steerable movable arm 74 accommodates all hydrogenerator sizes. A non-returnable connecting pipeline The area shown extends inside the tower 78. The loading and unloading station 75 allows the loading and unloading of the hydrogenerator 70 to and from the onshore facility 77. The latter includes liquefied gas storage tanks 80 and connecting pipelines 81 linked by the subsea pipeline 76 to the loading or unloading station 75. The subsea pipeline 76 allows the transfer of liquefied gas between the loading or unloading station 75 and the onshore facility 77 over a long distance, for example 5 km, which makes it possible to keep the hydrogenerator vessel 70 a long way from the coast during loading and unloading operations.

[0192] To generate the pressure necessary for the transfer of the liquefied gas, one can either use pumps on board the ship 70 and / or pumps equipping the land installation 77 and / or pumps equipping the loading and unloading station 75 or allow a rise in pressure in the internal space of the tank under the effect of the evaporation of the liquefied gas stored in the tank.

[0193] The invention applies to ship tanks 71 and also to land-based reservoirs and port structures.

[0194] Although the invention has been described in connection with several particular embodiments, it is clearly evident that it is by no means limited to them 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.

[0195] The use of the verb "comprise", "comprendre" or "include" and its conjugated forms does not exclude the presence of other elements or steps than those stated in a claim.

[0196] In claims, any reference sign in parentheses shall not be interpreted as a limitation of the claim.

Claims

Demands

1. Wall (10) for a sealed and thermally insulating tank for storing a liquefied gas, the wall (10) comprising successively, along a thickness direction, a secondary thermally insulating barrier (12) which rests against a load-bearing structure (1), a secondary sealing membrane (13) which rests against the secondary thermally insulating barrier (12), a primary thermally insulating barrier (14) which rests against the secondary sealing membrane (13) and a primary sealing membrane (15) which rests against the primary thermally insulating barrier (14) and is intended to be in contact with the liquefied gas contained in the tank; the primary thermally insulating barrier (14) comprising a plurality of load-bearing elements (30) which are fixed to the secondary thermally insulating barrier (13) and which rise along the thickness direction (D), and a radiative multilayer insulation blanket (47), which has openings (47A) through which the load-bearing elements (30) pass and which extends transversely to the thickness direction (D) of the wall, said multilayer insulation blanket (47) being fixed to one of the load-bearing elements (30) by a fixing device (51; 52; 53; 54; 55) comprising a connecting portion (511; 521; 531; 541; 551) fixed to said load-bearing element (30) and a support portion (512; 522; 532; 542; 552) extending transversely to the thickness direction (D) of the wall (10), said insulation cover (47) being fixed to said support part (512; 522; 532; 542; 552), in which the connecting part (511; 521; 531; 541;551) of the fastening device (51; 52; 53; 54; 55) comprises two portions (511A, 511B; 521A, 521B; 531A, 531B; 541A, 541B; 551A, 551B) movable relative to each other between a separation position in which the two portions (511A, 511B; 521A, 521B; 531A, 531B; 541A, 541B; 551A, 551B) are separated from each other to allow the carrier element (30) to be placed through the fastening device (51; 52; 53; 54; 55) such that the fastening device surrounds the carrier element (30), and a position of rapprochement in which the two portions (511 A, 511B ; 521 A, 521B ; 531 A, 53 IB ; 541A, 541B ; 551A, 551B) are brought closer together relative to the spacing position, so as to be able to immobilize the; fastening device on the load-bearing element by clamping the load-bearing element.

2. Wall according to claim 1, wherein the fixing device (51; 52; 53; 54; 55) is immobilized on the load-bearing element by bonding the fixing device (51; 52; 53; 54; 55) to the load-bearing element (30) and / or by elastic clamping of the load-bearing element (51; 52; 53; 54; 55) by the fixing device and / or by axial blocking of the fixing element (51; 52; 53; 54; 55) which rests on at least one stop element of the load-bearing element (30) extending outward from the load-bearing element (30).

3. Wall according to any one of claims 1 and 2, wherein said load-bearing element (30) has a central tubular part and the two portions (51 IA, 51 IB; 521A, 521B; 531A, 531B; 541A, 541B; 551A, 55 IB) of the connecting part (511; 521; 531; 541; 551) of the fastening device (51; 52; 53; 54; 55) form in their close-up position a collar whose internal dimensions are equal, within a clearance, to the external dimensions of the central part of the load-bearing element (30).

4. Wall according to any one of claims 1 to 3, wherein the connecting part (511; 521; 531) and the supporting part (512; 522; 532) of the fastening device (51; 52; 53) are made of one or more metal plates.

5. Wall according to any one of claims 1 to 4, wherein the two portions (511 A, 51 IB) of the connecting part (511) are linked by at least one hinge.

6. Wall according to any one of claims 1 to 4, wherein the two portions (521A, 521B) of the connecting part (521) are linked by at least one jumper (529).

7. Wall according to any one of claims 1 to 3, wherein the two portions (541 A, 541B; 551 A, 55 IB) of the connecting part (541; 551) belong to a metallic spring wire or a metallic spring blade.

8. Wall according to claim 7, wherein said spring wire or said spring blade forms a single turn or a plurality of turns around the bearing element (30).

9. A wall according to any one of claims 7 and 8, wherein the connecting portion (551) of the fastening device (55) is formed by a spring wire having folded and interlocking ends of so that they can move elastically apart from each other.

10. Wall according to any one of claims 1 to 9, wherein the support part (512; 522; 532; 542; 552) of the fastening device comprises at least one tab (512A; 522A; 532A; 542A; 552A) extending projecting from the connecting part (511; 521; 531; 541; 551).

11. Wall according to claim 10, wherein the tongue (512A; 532A) is formed or is attached to said connecting part of the fastening device.

12. Wall according to claim 11, wherein the two portions (541A, 541: 551A, 551B) of the connecting part (541; 551) belong to a metallic spring wire and the tab (542A; 552A) is formed by a fold of the wire or the spring blade.

13. Wall according to claim 11, wherein the tongue (512A, 522A) is formed by folding a metal plate (513; 523) forming one of the two portions of the connecting part (511; 521).

14. Wall according to claim 11, wherein the tongue (532A) is formed by welding a metal plate onto one of the two portions of the connecting part (531).

15. Wall according to any one of claims 1 to 14, wherein the support part (512; 522; 532; 542; 552) of the fixing device (51; 52; 53; 54; 55) comprises a fixing element (518; 528; 538; 548; 558) of the multilayer insulation cover (47) adapted to cooperate with a complementary fixing element (560) of the fixing device.

16. Wall according to claim 15, wherein the fixing element of the multilayer insulation cover is an opening, the complementary fixing element of the fixing device comprises a fir tree clip, a pin or a rivet and the multilayer insulation cover has an opening located opposite this through-hole of the fixing element which is traversed by the fir tree clip, the pin or the rivet.

17. A sealed and thermally insulating tank integrated into a load-bearing structure, the load-bearing structure comprising a plurality of load-bearing walls, the tank comprising a plurality of tank walls fixed each time to a respective load-bearing wall, of which a tank wall conforms to any one of claims 1 to 16.

18. Vessel (70) for the transport of a fluid, the vessel comprising a double hull (72) and a tank (71) according to claim 17 disposed in the double hull (72).

19. Transfer system for a liquefied gas, the system comprising a vessel (70) according to claim 18 and insulated pipelines (73, 79, 76, 81) arranged to connect the tank (71) installed in the hull of the vessel to a floating or land-based storage facility (77).

20. A method of loading or unloading a ship (70) according to claim 18, wherein a liquefied gas is conveyed through insulated pipelines (73, 79, 76, 81) from or to a floating or land-based storage facility (77) to or from the tank (71) of the ship (70).

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