Sealed and thermally insulating tank

Abstract

A sealed and thermally insulating tank for the storage of a fluid, integrated into a supporting structure, comprises, in succession in a thickness direction: a thermally insulating barrier mounted on the supporting structure, and a sealing membrane supported by the thermally insulating barrier, the thermally insulating barrier comprising insulating panels arranged in the form of at least two parallel rows separated by an interspace, the thermally insulating barrier comprising flat seals (77, 78) arranged in the interspace such that they are compressed between the two rows, the thermally insulating barrier further comprising at least one insert (8) arranged in a contiguity region (9) where a first flat seal (77) and a second flat seal (78) are contiguous so as to compress the insert (8) between the flat seals (77, 78) in the interspace.

Description

Technical field of the invention

[0001] The invention relates to the field of leak-proof and thermally insulated membrane tanks. In particular, the invention relates to the field of leak-proof and thermally insulated tanks for the storage and / or transport of low-temperature liquids, such as tanks for transporting Liquefied Petroleum Gas (LPG) at temperatures ranging, for example, from -50°C to 0°C, or for transporting 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 used for transporting liquefied gas or for receiving liquefied gas to serve as fuel for the propulsion of the floating structure. Technological background

[0002] French patent application FR2781557 describes a watertight and insulating tank comprising two thermally insulating barriers. These insulating barriers consist of a set of prefabricated panels. The junction area between the prefabricated panels is filled with strips of thermally insulating material such as glass wool.

[0003] In French patent application FR2599468, a sealed and thermally insulating tank integrated into a load-bearing structure is proposed. Cellular foam panels, forming a thermally insulating barrier, are attached to this structure. To ensure the continuity of the thermally insulating barrier, the spaces between the panels are filled with spacers.

[0004] French patent application FR2813111 describes a watertight and thermally insulating tank integrated into a load-bearing structure. The load-bearing structure comprises a first load-bearing wall and a second load-bearing wall forming an angle and meeting at an edge. Each load-bearing wall includes panels forming a thermally insulating barrier. Thermal continuity between the two thermally insulating barriers at the edge is ensured by a glass wool seal. Thermal continuity within each thermally insulating barrier is ensured by the insertion of a sheet of glass wool folded over itself.

[0005] The fiberglass spacers recommended in the publications cited above are not entirely satisfactory. Indeed, gaps conducive to convection between the outside and inside of the tank, particularly in the presence of liquefied natural gas, are likely to appear at these spacers.

[0006] Alternatively, Japanese patent application JPH4194498 describes flat gaskets comprising an insulating material, such as glass wool or polyurethane, wrapped in a sealed plastic film bag. The flat gaskets are inserted in a vacuum-compressed state into the inter-panel spaces. Once inserted, the bag is punctured to allow the gasket to expand and fill the entire inter-panel space. However, the applicant observed that these flat gaskets contract more than the inter-panel space in which they are housed at low temperatures. This contraction results in the formation of gaps between the flat gaskets and the panel faces that define the inter-panel space. Such gaps promote convection and are detrimental to the continuity of the thermally insulating barrier. Document EP0543686A1 discloses a sealed and thermally insulating tank. Summary

[0007] One idea underlying the invention is to provide a sealed and thermally insulating tank that does not present these drawbacks. Thus, the aim of the invention is to better control the thermal continuity of the thermally insulating barriers, particularly in a longitudinal direction of the space between at least two rows of blocks composing the thermally insulating barriers, during the cooling of said tank.

[0008] To this end, the present invention relates to a sealed and thermally insulated fluid storage tank integrated into a load-bearing structure, comprising successively in a thickness direction a load-bearing structure, a thermally insulating barrier retained on the load-bearing structure, and a sealing membrane supported by the thermally insulating barrier, the thermally insulating barrier comprising insulating panels arranged in the form of at least two parallel rows, the two rows of insulating panels being separated by an intervening space having a small width compared to the dimensions of the insulating panels, the thermally insulating barrier further comprising flat joints, the flat joints being arranged in the intervening space so as to be compressed between the two rows of insulating panels,the thermally insulating barrier further comprising at least one insert arranged in a contiguous zone where a first flat joint and a second flat joint are contiguous so as to compress the insert between the flat joints in a longitudinal direction of the intervening space.

[0009] The flat gaskets are compressed between two rows after being inserted into the gap. When the tank is cooled, the insulation panels and the flat gaskets will contract. However, the flat gaskets will not contract enough to create gaps between the insulation panels and the gaskets. Thus, thermal continuity is always maintained across the width of the gap.

[0010] According to one embodiment, the flat joints are compressed only in the direction of the width of the gap, in particular after being inserted into the gap.

[0011] In one embodiment, the compression of the flat joints is greater in the width direction of the gap than in the longitudinal direction of the gap. In this embodiment, the adjacent flat joints have been pushed or pressed towards each other in the longitudinal direction so that, prior to the insertion of the insert, there is an initial compressive force in a longitudinal direction of the gap, this initial compressive force being less than the compressive force of the flat joints between two rows of insulation panels.

[0012] The flat gaskets are not under, or are only slightly under, compression in the longitudinal direction of the interlayer space. A gap can therefore easily form in an area of ​​contiguity where two flat gaskets are adjacent during tank cooling. Adding the insert will compress the flat gaskets and the insert itself in the longitudinal direction of the interlayer space. Thus, during tank cooling, the gaskets will contract due to the cold, but not enough to create gaps conducive to convection. Thermal continuity is therefore ensured in the longitudinal direction of the interlayer space thanks to the compressed insert between the two flat gaskets.

[0013] In addition, the tank may possess the following characteristics, considered individually or in combination.

[0014] Advantageously, flat gaskets consist of a compressible insulating material partially or completely covered by a foil envelope. Such an envelope can facilitate the sliding of the flat gasket against the side walls of the insulation panels during insertion. If closed, such an envelope can also be used to create a vacuum to thin the flat gasket during insertion.

[0015] Advantageously, the insert comprises a backing sheet folded in half to form a pleat, and a layer of compressible insulating material arranged at least partially inside said pleat. This backing sheet facilitates the sliding of the insert against the flat joints during installation.

[0016] In one embodiment, the insert extends along the thickness direction of the tank, with the fold facing the supporting structure. This fold can easily be pushed into place between the flat joints.

[0017] The space between the two rows can extend over one or more flat walls of the tank. According to one embodiment, the load-bearing structure comprises a first load-bearing wall and a second load-bearing wall forming an angle and meeting at an edge, the two rows being oriented transversely to the edge, the first flat joint being arranged in a first portion of the space between at least two insulating panels located on the first load-bearing wall, the second flat joint being arranged in a second portion of the space between at least two insulating panels located on the second load-bearing wall.

[0018] According to one embodiment, the contiguity zone is located at the edge.

[0019] Advantageously, the flat joint has a longitudinal end face inclined relative to the longitudinal direction of the gap.

[0020] According to one embodiment, the inclined longitudinal end face of the flat joint is substantially parallel to a bisector of the angle between the first and second load-bearing walls.

[0021] According to one embodiment, the inclination between the end face and the longitudinal direction of the intercalated space is between 45°, for example for an angle of 90° between the two walls, and 68° for example for an angle of 135° between the two walls.

[0022] Advantageously, the compressible insulating material of the flat joint includes laminated glass wool and / or rock wool.

[0023] According to one embodiment, the laminated glass wool has a density between 20 and 80 kg / m³.

[0024] According to one embodiment, the direction of stratification of the laminated glass wool is parallel to a width direction of the interlayer space.

[0025] Advantageously, the sheet material envelope of the flat gasket includes paper.

[0026] According to one embodiment, the paper has a basis weight of between 60 and 150 g / m², preferably between 70 and 100 g / m².

[0027] Advantageously, the backing sheet comprises paper and / or PVC.

[0028] Advantageously, the backing sheet includes an adhesive strip onto which the insulating material layer is glued.

[0029] Advantageously, the insulating compressible material layer comprises a fibrous material, for example glass wool, or a polymer foam, for example polyethylene or polyurethane.

[0030] Advantageously, the insulating panels of the thermally insulating barrier include polymer foam blocks.

[0031] According to one embodiment, the polymer foam blocks comprise polyurethane.

[0032] According to one embodiment, polyurethane has a density between 70 kg / m³ and 220 kg / m³.

[0033] According to one embodiment, the thermally insulating barrier fixed to the supporting structure is a secondary thermally insulating barrier, the sealing membrane fixed on the secondary thermally insulating barrier being a secondary sealing membrane, the tank further comprising, in the thickness direction, from the outside to the inside, over the secondary thermally insulating barrier and the secondary sealing membrane, a primary thermally insulating barrier and a primary sealing membrane intended to be in contact with the liquid contained in the tank.

[0034] According to one embodiment, the invention also provides a method for manufacturing a sealed and thermally insulated tank for storing a fluid, comprising a step of depositing insulating panels arranged in the form of at least two parallel rows on a supporting structure, the two rows of insulating panels being separated by an intercalated space having a small width compared to the dimensions of the insulating panels, a step for inserting flat gaskets into the intercalated space so as to compress the flat gaskets between the two rows of insulating panels, and a step for inserting an insert in a contiguity zone between two flat gaskets so as to compress the insert between the flat gaskets in a longitudinal direction of the intercalated space.

[0035] It should be noted here that the step of inserting a gasket into the contiguous zone between two flat gaskets can optionally be carried out during the manufacturing of the flat gasket itself. In this case, the gasket is equipped with an insert fixed to the area intended to form the contiguous zone of the flat gasket, for example, by gluing or stapling. The inserting step consists of pushing at least the flat gasket already equipped with the insert against the other adjacent flat gasket, which may also be equipped with an insert or part of an insert. Naturally, in this embodiment, the insert or part of an insert previously fixed to the flat gasket can have a shape adapted to the aforementioned compression function of the insert, for example, a triangular cross-section with a greater thickness in the upper part of the flat gasket (once it is installed in the tank).

[0036] In the following, the invention is presented in accordance with its preferred, and non-limiting, embodiment, in which the step of intercalating the insert in the contiguity zone between two flat joints is carried out, or performed, following the mounting / assembly of a set of insulating panels on one or more walls of the tank.

[0037] According to one embodiment, the process further comprises a step in which a depression is applied in the envelope so as to reduce the thickness of said flat joints when the flat joints are inserted into the gap, the flat joints comprising a compressible insulating material partially or totally covered by a sheet material envelope.

[0038] According to one embodiment, the insert is folded in half before being inserted into the contiguous area by exerting a push in a part of the bottom of the fold.

[0039] According to one embodiment, the insert is inserted into the contiguity zone, in which the insert is forcibly inserted into the contiguity zone.

[0040] Such a tank can be part of an onshore storage facility, for example for storing LNG, or be installed in a floating structure, whether coastal or deep-water, including an LNG carrier, a floating storage and regasification unit (FSRU), a floating production and storage unit (FPSO), and others. Such a tank can also serve as a fuel tank in any type of vessel.

[0041] According to one embodiment, a ship for the transport of a cold liquid product comprises a double hull and the aforementioned tank arranged in the double hull.

[0042] According to one embodiment, the invention also provides a method for loading or unloading such a vessel, 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 vessel's tank.

[0043] According to one embodiment, the invention also provides a transfer system for a cold liquid product, the system comprising the aforementioned vessel, insulated pipes arranged to connect the tank installed in the hull of the vessel to a floating or land-based storage facility, and a pump to drive 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. Brief description of the figures

[0044] 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. There figure 1 is an exploded cross-sectional view of a tank area located at the angle between two flat walls, the cutting plane being parallel to a row of insulating panels. There figure 2 is a schematic cutaway representation of a flat joint being inserted into an inter-panel space. There figure 3 is a schematic perspective view of angle zone III of the figure 1 during the insertion of two flat gaskets using a vacuum pump; There figure 4 is a schematic perspective view of two contiguous flat joints suitable for a 135° tank angle. There figure 5 is a schematic perspective view of two contiguous flat joints suitable for a 90° tank angle. There figure 6 is a schematic top view of the thermally insulating barrier and flat joints inserted in the inter-panel spaces; There figure 7 is a schematic cross-sectional view of the insulating insert; There figure 8 is a schematic cross-sectional view along plane VIII-VIII of the figure 3 of the intercalation of the insert between two adjacent flat joints in a corner of the tank; There figure 9 is a schematic cutaway representation of a tank on an LNG carrier and a loading / unloading terminal for that tank. Detailed description of implementation methods

[0045] 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. A sealed and thermally insulated tank for the storage and transport of a cryogenic fluid, for example Liquefied Natural Gas (LNG), comprises a plurality of tank walls, each with a multilayer structure.

[0046] By referring in particular to the figure 1 We see a tank 1 made of sealed and thermally insulated walls, for example for storing and / or transporting a fluid at very low temperature. Here, and this is only an example, such as a very cold liquefied gas, such as methane.

[0047] Tank 1 comprises a sealed inner shell suitable for containing the fluid to be stored, which is made up of prefabricated elements assembled together to form, for each wall of tank 1, a sealing membrane 4. On the figure 1 The sealing membrane 4 is formed by thin metal elements such as stainless steel or aluminum sheet. Reference 41 designates ribs projecting towards the inside of the tank, which allow the envelope formed by this barrier to be substantially flexible, so as to be able to deform under the effect of stresses, particularly thermal stresses generated by the fluid stored within it.

[0048] A rigid external bulkhead forms the load-bearing structure 2 of the tank 1 and acts as a support for the latter. Following the illustrated example, this load-bearing structure 2 is a self-supporting metal plate of the hull or double hull of a merchant ship, such as an LNG carrier. Other types of rigid bulkheads with suitable mechanical properties, such as a concrete wall in a land-based structure, may be used to support the tank 1. Furthermore, a secondary thermally insulating barrier 3, a secondary sealing membrane 16, and a primary insulating barrier 15 are provided between the sealing membrane 4 and the load-bearing structure 2.

[0049] The secondary thermally insulating barrier 3 is formed by the juxtaposition of insulating panels 5, which are generally rectangular prismatic in shape. The insulating panels 5 are generally arranged end-to-end and thus configured to define parallel rows 51, 52 covering the entire load-bearing structure. On the figure 1 The row of insulating panels 5 is parallel to the cutting plane. As visible on the figures 2 And 3 , two rows 51, 52 of insulating panels 5 are separated by an interlayer space 6. This interlayer space 6 is generally linear and usually extends over at least the entire thickness of the insulating panels 5. In addition, the interlayer space 6 has a small width E compared to the dimensions of the insulating panels 5.

[0050] Furthermore, the load-bearing structure 2 also has edges 10. These edges 10 of the load-bearing structure 2 are formed by a first load-bearing wall 21 and a second load-bearing wall 22 defining an angle A. As can be seen on the figure 3 , two rows 51, 52 are oriented transversely to the edge 10. The insulating panels 5 can be beveled with an angle appropriate to that which is formed by the supporting structure 2 at the level of these edges 10.

[0051] Insulating panels 5 can preferably be prefabricated with standard dimensions.

[0052] On the figure 6 which illustrates a flat wall of the tank 1, the fitting filling the gap 6 between two parallel rows 51, 52 of insulating panels 5 to ensure the continuity of the thermally insulating barrier 3 is obtained by inserting a plurality of flat joints 7.

[0053] At a corner A of the tank 1, two adjacent flat gaskets form an angle with each other, as illustrated by the flat gaskets 7 on the figure 3 ; 75, 76 on the figure 4 ; and 77, 78 on the figure 5 .

[0054] As seen on the figure 2 , each flat joint 7, 75, 76, 77, 78 comprises a compressible insulating material 72 covered at least partially by a sheet material envelope 71. Preferably the sheet material envelope 71 completely surrounds the compressible insulating material 72 and forms a closed pocket in which it is possible to generate a vacuum.

[0055] Compressible insulating material 72 can be made of glass wool. The glass wool used can be laminated glass wool, that is, a glass wool mat made up of multiple parallel, interwoven layers, visible to the naked eye, which are superimposed in a single direction of lamination. The fibers can therefore be predominantly oriented in planes perpendicular to the direction of lamination. Laminated glass wool can have a density between 20 and 80 kg / m³. Alternatively, rock wool can be used as compressible insulating material 72.

[0056] On the figures 2 to 5The sheet material envelope 71 comprises portions of the envelope fixed, for example by gluing, to the compressible insulating material 72, i.e., to the glass wool. The envelope portions 71 completely cover the compressible insulating material 72. The envelope 71 is made of kraft paper. Such kraft paper offers a low coefficient of friction, thus allowing the flat seal 7, 75, 76, 77, 78 to slide within the gap 6 when inserted into said gap 6. Furthermore, such kraft paper has a coefficient of thermal contraction on the order of 5 to 20 x 10⁻⁶ / K. Thus, such kraft paper has a coefficient of thermal contraction close to that of the compressible insulating material 72. Therefore, the flat seal 7, 75, 76, 77, 78 exhibits uniform cold performance.Indeed, the compressible insulating material 72 is not at risk of deforming under compression due to the thermal contraction of the sheet material envelope 71. In particular, the compressible insulating material is not at risk of deforming into a corrugated shape under this compression, as such a corrugated shape would create gaps in the interlayer space 6, promoting convection and thus detrimental to the insulating properties of the thermally insulating barrier. The kraft paper of the envelope 71 has a basis weight greater than 60 g / m² to prevent the risk of tearing the envelope 71 when the flat seal 7 is inserted into the interlayer space 6. Furthermore, this kraft paper has a basis weight less than 150 g / m² so that the envelope 71 retains sufficient flexibility to allow the flat seal 71 to deform under compression. Preferably the grammage of the kraft paper is between 70 and 100 g / m².

[0057] The flat joints 7, 75, 76, 77, and 78 have an elongated shape with a rectangular parallelepiped cross-section corresponding to the rectangular cross-section of the gap 6. Thus, the flat joint has two parallel lateral faces extending along a longitudinal direction of the gap. Longitudinal end faces 79 extend along the width E of the gap 6 and connect the lateral faces.

[0058] However, some flat joints may take an alternative form, particularly at the edge of a corner structure as described above. Such examples of flat joints 75, 76, 77, 78 are illustrated in the figures 3 and 4The flat joints 75, 76, 77, and 78 have a longitudinal end face 79 inclined at the edge 10 of the corner structure. This inclined longitudinal end face 79 forms an angle of 45° and 67.5° respectively with the longitudinal direction of the spacer 6, so as to correspond to the bisector of angle A of the tank. In other words, these flat joints 75, 76, 77, and 78 have a right trapezoidal contour.

[0059] More generally, the shape of flat joints is not limited to that described above and can be adapted according to the constraints encountered.

[0060] The procedure for inserting the flat gasket into the gap will now be described with regard to the figure 3 This insertion method uses a suction system. Such a suction system is, in the following description, by way of example, a vacuum pump 11 as illustrated in the figure 3 In an embodiment not shown, such a suction system is a Venturi-type vacuum generator. Such a vacuum pump 11 is connected to a suction nozzle 13 via a pumping hose 12. The suction nozzle 13 has a frustoconical shape so as to provide an end opposite the pumping hose 12 that is capable of perforating the kraft paper sleeve 71. Thus, the suction nozzle 13, and more specifically its perforation end, is inserted into the flat seal 7 by perforating the kraft paper sheet sleeve 71. This perforation of the sleeve 71 creates a suction opening in the flat seal.

[0061] Once the suction nozzle 13 is inserted into the flat seal 7 and correctly positioned, the vacuum pump 11 is activated to create a vacuum in the flat seal 7. The suction generated by the vacuum pump 11 has a flow rate between 8 and 30 m³ / h. Preferably, the pumping rate is 15 m³ / h. Such a pumping rate of the vacuum pump 11 makes it possible to generate a vacuum in the flat seal 7 without risking damage to the kraft paper casing 71 due to an excessive suction rate. Preferably, the vacuum pump 11 includes a filter to remove any fibers and dust from the glass wool that may be drawn in by the vacuum pump 11.

[0062] The description above mentions kraft paper for making envelope 71. Other materials can also be used to make all or part of envelope 71. These materials include, for example, polymer sheets, composite sheets comprising mineral fibers and a polymer matrix, composite sheets comprising mineral fibers bonded to a sheet of paper or polymer, and combinations thereof. The polymer can be a resin selected from the group consisting of polyethylene (PE), polypropylene (PP), polyethylene terephthalate (PTE), and polyvinyl chloride (PVC). In particular, the envelope can be manufactured as an assembly of several portions obtained by cutting one or more sheet materials from the list above.

[0063] Typically, the flat gasket 7 is dimensioned to have, in its free state (i.e., uncompressed), a thickness greater than or equal to the width of the gap 6, and under vacuum by means of the vacuum pump 11, a thickness less than said width of the gap 6. For example, for a gap 6 between 33 mm and 27 mm, the flat gasket 7 is dimensioned to have an initial thickness (i.e., in its free state) of 35 mm and, under vacuum, a thickness of 25 mm. The flat gasket 7 is then inserted into the gap 6. As illustrated in the figure 3By means of arrows 14, the flat gasket 7 is inserted into the gap 6 with its lateral faces parallel to the lateral faces of the adjacent insulating panels 5 delimiting the gap 6. During this insertion, the suction nozzle 13 is held in the flat gasket 6 and the vacuum pump 11 continuously generates a vacuum in said flat gasket 7 in order to keep the flat gasket 7 in its vacuum state in order to facilitate its insertion into the gap 6 since the flat gasket 7 then has a thickness less than the width of the gap 6.

[0064] The flat seal 7 is inserted into the spacer 6 so that the lateral face through which the suction nozzle 13 passes is turned towards the inside of the tank, thus facilitating the handling of the assembly formed by the flat seal 7 and the suction nozzle 13.

[0065] Once the flat gasket 7 is correctly positioned in the gap 6, the suction nozzle 13 is removed from the flat gasket 7. At this point, the interior of the envelope 5 is open to the outside environment through the opening created by the suction nozzle 13. This opening allows the glass wool 11, since the vacuum is no longer maintained in the flat gasket 7, to expand in the absence of compressive stress. The expansion of the glass wool 72 increases the thickness of the flat gasket 7 so that the flat gasket 7 completely fills the gap 6, thus ensuring good continuity of the thermally insulating barrier.

[0066] In an embodiment not shown, a rigid guide system can be used as a guide tool when inserting the flat gasket 7 into the gap 6.

[0067] There figure 6is an illustration of the position occupied by the flat joints after being arranged in the space between 6 formed by a first row 51 of insulating panels 5 and a second row 52 of insulating panels 5. It is noted that the flat joints 7 are contiguous with each other at the level of their longitudinal end faces.

[0068] Finally, on the figure 8It is observed that the flat gaskets 77, 78 in the gap spanning two walls, i.e., at the level of a corner structure, can be contiguous via their inclined longitudinal end faces. Once flat gaskets 7 and / or 75, 76 and / or 77, 78 have been installed along the entire length of the gap 6, the clamping force between two contiguous flat gaskets in the longitudinal direction of the gap 6 may be insufficient in places, particularly at the edge 10 of the supporting structure 2. When this clamping force is insufficient, a gap is likely to appear at the junction between the two flat gaskets during the cooling of the tank, notably due to the thermal contraction of the flat gaskets. Where this clamping force is insufficient, an insert is introduced between the two flat gaskets.The contiguity zone 9 observed between the two inclined longitudinal end faces is intentionally exaggerated for understanding the insertion of the insert 8. To complete the continuity of the insulating thermal barrier over the entire length of the intercalated space 6, inserts can be intercalated between two consecutive flat joints.

[0069] With reference to the figure 7 An insert 8 comprises a support sheet 81 having two faces, and a layer of compressible insulating material 82 on one of the two faces. The unfolded insert has a rectangular shape whose width corresponds to the width E of the intervening space 6. Since the insert is to be interposed between two adjacent flat joints 7 or 75 / 76 or 77 / 78, the length of the insert represents twice the thickness of the secondary insulating barrier 3.

[0070] The compressible insulating layer 82 can be made of glass wool. The glass wool used can be laminated glass wool, that is, a glass wool mat made up of multiple layers of interwoven parallel fibers, visible to the naked eye, which are superimposed in a single direction of lamination. The fibers can therefore be predominantly oriented in planes perpendicular to the direction of lamination. Laminated glass wool can have a density between 20 and 80 kg / m³. Alternatively, rock wool can be used for the compressible insulating layer 82.

[0071] The support sheet 81 can be made of kraft paper to which the layer of compressible insulating material 82, i.e., glass wool, is attached, for example with glue. The kraft paper offers a low coefficient of friction, thus allowing the insert to slide. The support sheet 81 has two sides. The glass wool partially or completely covers one side of the kraft paper.

[0072] To insert insert 8 into the adjacent zone 9, insert 8 is first folded in half lengthwise. The fold can then take the form of a U as shown in the figure 7This U-shaped fold can be limited to a portion of the end of the insert 8. The fold is made ensuring that at least part of the fiberglass is oriented inside the fold. The curved part of the fold is then positioned at the contiguous zone. A flat, rectangular-bladed knife is inserted into the fold. Once at the bottom of the fold, the knife is used to push the insert into the contiguous zone until it is completely sandwiched between two flat joints 7. Although the kraft paper facilitates sliding the insert between two flat joints, the insert can be forced into place.

[0073] The description above mentions kraft paper for producing backing sheet 81. Other materials can also be used to produce backing sheet 81. These materials include, for example, polymer sheets, composite sheets comprising mineral fibers and a polymer matrix, composite sheets comprising mineral fibers bonded to a paper or polymer sheet, and combinations thereof. The polymer can be a resin selected from the group consisting of polyethylene (PE), polypropylene (PP), polyethylene terephthalate (PTE), and polyvinyl chloride (PVC).

[0074] The description below is given with reference to a secondary insulating barrier 3. However, the same technique can be used to create the primary insulating barrier of a tank or the single insulating barrier of a tank consisting of only one sealing membrane.

[0075] The technique described above for making a sealed and thermally insulating tank can be used in different types of tanks for example in a land-based installation or in a floating structure such as a methane tanker or other.

[0076] With reference to the figure 9 A cutaway view of a LNG carrier 100 shows a sealed and insulated tank 1 of generally prismatic shape mounted in the double hull 101 of the ship. The tank 1 comprises a primary sealed barrier intended to be in contact with the LNG contained in the tank, a secondary sealed barrier arranged between the primary sealed barrier and the double hull 101 of the ship, and two insulating barriers arranged respectively between the primary sealed barrier and the secondary sealed barrier and between the secondary sealed barrier and the double hull 101.

[0077] There figure 9This represents an example of a marine terminal comprising a loading and unloading berth 102, a subsea pipeline 103 and an onshore installation 104. The loading and unloading berth 102 is a fixed offshore installation comprising a movable arm 105 and a tower 106 which supports the movable arm 105. The movable arm 105 carries a bundle of insulated flexible pipes 107 which can be connected to the loading / unloading pipelines 108. The steerable movable arm 105 adapts to all LNG carrier sizes. An unshown connecting pipeline extends inside tower 106. The loading and unloading station 102 allows the loading and unloading of the ship 100 from or to the onshore facility 104. This facility includes liquefied gas storage tanks 109 and connecting pipelines 110 linked by the subsea pipeline 103 to the loading and unloading station 103.The subsea pipeline 103 allows the transfer of liquefied gas between the loading and unloading station 102 and the onshore facility 104 over a long distance, for example 5 km, which allows the ship 100 to be kept a long distance from the coast during loading and unloading operations.

[0078] To generate the pressure necessary for the transfer of the liquefied gas, pumps on board the ship 100 and / or pumps equipping the land installation 105 and / or pumps equipping the loading and unloading station 102 are used.

[0079] Although the invention has been described in connection with several particular embodiments, it is clear that it is by no means limited to them and that it includes all technical equivalents of the means described, as well as combinations thereof, if these fall within the scope of the invention. The scope of the invention is that as defined by the claims.

[0080] The use of the verb "comporter", "comprendre" or "include" and its conjugated forms does not exclude the presence of other elements or steps than those stated in a claim.

[0081] In claims, any reference sign in parentheses should not be interpreted as a limitation of the claim.

Claims

1. A sealed and thermally insulated tank (1) for the storage of a fluid, integrated into a supporting structure (2), including, in succession in a thickness direction: a thermally insulating barrier (3) retained on the supporting structure (2), and a sealing membrane (4) supported by the thermally insulating barrier (3), the thermally insulating barrier (3) including insulating panels (5) arranged in the form of at least two parallel rows (51, 52), the two rows (51, 52) of insulating panels (5) being separated by a gap (6) having a small width (E) compared to the dimensions of the insulating panels, the thermally insulating barrier (3) further including gaskets (7), the gaskets being arranged in the gap (6) in such a manner that they are compressed between the two rows (51, 52) of insulating panels (5), characterized in that the thermally insulating barrier (3) further includes at least one insert (8) arranged in a contiguity zone (9) where a first gasket (7) and a second gasket (74) are contiguous in such a manner as to compress the insert (8) between the gaskets (7) in a longitudinal direction of the gap (6).

2. The tank (1) as claimed in the preceding claim, in which the gaskets (7) include a compressible insulating material (72) covered partly or entirely by a sheet material envelope (71).

3. The tank (1) as claimed in either one of the preceding claims, in which the insert (8) includes a support film (81) folded into and thus forming a pleat (83) and a layer of compressible insulating material (82) arranged at least in part inside said pleat (83).

4. The tank (1) as claimed in the preceding claim, in which the insert (8) extends in the direction of thickness of said tank (1), the pleat (83) being oriented toward the support structure (2).

5. The tank (1) as claimed in the preceding claim, in which the support structure (2) includes a first support wall (21) and a second support wall (22) forming an angle (A) and joining at the level of an edge (10), the two rows (51, 52) being oriented transversely to the edge (10), the first gasket (7, 75, 77) being arranged in a first portion of the gap (6) separating at least two insulating panels (5) situated on the first support wall (21), the second gasket (7, 76, 78) being arranged in a second portion of the gap (6) separating at least two insulating panels (5) situated on the second support wall (22).

6. The tank (1) as claimed in the preceding claim, in which the contiguity zone (9) is situated in line with the edge (10).

7. The tank (1) as claimed in any one of the preceding claims, in which the gasket (7) has a longitudinal end face (75) inclined relative to the longitudinal direction of the gap (6).

8. The tank as claimed in either one of claims 5 to 6 with claim 7, in which the inclined longitudinal end face (75) of the gasket (7) is substantially parallel to a bisector of the angle (A) between the first and second support walls (21, 22).

9. The tank (1) as claimed in either one of claims 7 or 8, in which the inclination between the end face (75) and the longitudinal direction of the gap (6) is between 45° and 68° inclusive.

10. The tank (1) as claimed in any one of the preceding claims, in which the compressible insulating material (72) of the gasket includes a laminated glass wool.

11. A ship (100) for transporting a cold liquid product, the ship including a double hull (101) and a tank disposed in the double hull, the tank being a tank (1) as claimed in any one of claims 1 to 10.

12. A system for transferring a cold liquid product, the system including a ship (100) as claimed in claim 11, insulated pipes (103, 107, 108, 110) arranged in such a manner as to connect the tank (1) installed in the hull of the ship to a floating or terrestrial storage installation (104) and a pump for driving a flow of cold liquid product through the insulated pipes from or to the floating or terrestrial storage installation to or from the tank of the ship.

13. A method of manufacturing a sealed and thermally insulating tank (1) for storing a fluid, including the following steps: - depositing insulating panels (5) arranged in the form of at least two parallel rows (51, 52) on a support structure (2), the two rows (51, 52) of insulating panels (5) being separated by a gap (6) having a width (E) that is small compared to the dimensions of the insulating panels (5); - inserting gaskets (7) in the gap (6) so as to compress the gaskets between the two rows (51, 52) of insulating panels (5); - arranging a sealing membrane (4) supported by the thermally insulating barrier, characterized in that the method comprises: - interleaving an insert (8) in a contiguity zone (9) between two flat gaskets (7, 75, 76, 77, 78) in such a manner as to compress the insert (8) between the gaskets (7, 75, 76, 77, 78) in a longitudinal direction of the gap (6).

14. The method as claimed in the preceding claim, in which the gaskets (7, 73, 74) include a compressible insulating material (72) entirely covered by a film material envelope (71) and in which a reduced pressure is applied in the envelope in such a manner as to reduce the thickness of said gaskets (7, 75, 76, 77, 78) when inserting the gaskets (7, 75, 76, 77, 78) in the gap (6).

15. The method as claimed in either one of claims 13 and 14, in which the insert (8) is folded in two before being inserted in the contiguity zone (9) by exerting a thrust in a bottom part of the pleat.

16. The method as claimed in claim 15, in which the insert (8) is inserted in the continuity zone (9), in which the insert (8) is forcibly inserted in the contiguity zone (9).

17. A method of loading or offloading a ship (100) as claimed in claim 11, in which a cold liquid product is routed through insulated pipes (103, 107, 108, 110) from or to a floating or terrestrial storage installation (104) to or from the tank (1) of the ship.

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