sealed and thermally insulated tank

Abstract

The invention relates to a sealed and thermally insulated tank comprising a thermal insulation barrier and a sealing membrane, the tank comprising a channel (29) extending in a longitudinal direction along the sealing membrane, the thermal insulation barrier forming a bottom (36) of the channel (29), the tank further comprising a closure member (30) comprising a flexible membrane comprising a first fixing region (31, 33) and a second fixing region (32), the first fixing region extending transversely to the longitudinal direction of the channel (29) and being fixed to the bottom (36) of the channel (29), the second fixing region extending transversely to the longitudinal direction of the channel (29) and being fixed to the sealing membrane, the flexible membrane comprising a closure portion (34, 35) interposed between the first fixing region (31, 33) and the second fixing region (32), the closure portion (34, 35) closing the channel (29) to create a pressure loss in the channel.

Description

Technical Field

[0001] This invention relates to the field of membrane-sealed and thermally insulated tanks for storing and / or transporting fluids, particularly cryogenic fluids.

[0002] Membrane-sealed and thermally insulated tanks are particularly suitable for storing liquefied natural gas (LNG) at atmospheric pressure and temperatures of approximately -162°C. These tanks can be installed on onshore or floating structures. In the case of floating structures, the tanks can be used for transporting LNG or for receiving LNG used as fuel to propel the floating structure. Background Technology

[0003] In the prior art, sealed and thermally insulated tanks for storing liquefied natural gas are known, which are incorporated into the support structure of a vessel used for transporting liquefied natural gas, such as a catamaran. Typically, such tanks comprise a multi-layered structure having, in the thickness direction from the outside to the inside of the tank: a secondary thermal barrier held on the support structure; a secondary sealing membrane abutting the secondary thermal barrier; a primary thermal barrier abutting the secondary sealing membrane; and a primary sealing membrane abutting the primary thermal barrier and intended to contact the liquefied natural gas contained within the tank.

[0004] Document WO2016 / 046487 describes a secondary thermal barrier and a primary thermal barrier formed by juxtaposed insulating plates. In WO2016 / 046487, the secondary sealing membrane is composed of multiple metal sheets, each including corrugated portions protruding outwards from the tank, thus allowing the secondary sealing membrane to deform under the influence of thermal and mechanical strain generated by the fluid stored in the tank. The inner surfaces of the insulating plates of the secondary thermal barrier have grooves that receive the corrugated portions of the corrugated metal sheets of the secondary sealing membrane. These corrugated portions and these grooves form a mesh of channels extending along the tank wall.

[0005] Document WO2014167214A2 describes a corner structure of a multi-layered sealed and thermally insulated can. In the multi-layered sealed and thermally insulated can, the secondary thermal insulation barrier includes two insulating plates forming an edge at the corner between the two walls of the can. The secondary sealing membrane includes a flexible sealing membrane aligned with the edge, which connects the secondary sealing membrane portions of the two walls of the can.

[0006] The central portion of the flexible sealing membrane, that is, the portion of the flexible sealing membrane located between the secondary sealing membrane portion anchored to the two walls of the can, is not anchored to the secondary thermal insulation barrier and is therefore free relative to the secondary thermal insulation barrier.

[0007] Therefore, when the sealed and thermally insulated container is cooled, the thermal shrinkage of the insulating plate forming the edge and the sealing film is absorbed by the deformation of the central portion of the flexible sealing film, which is typically tensioned to absorb the strain associated with this shrinkage. However, when the flexible film is tensioned, a gap appears between the central portion of the flexible sealing film and the thermal insulation barrier, or the gap between the central portion of the flexible sealing film and the thermal insulation barrier increases. This gap extends along the entire length of the edge.

[0008] These gaps create channels that promote convection and are therefore likely to reduce the thermal insulation efficiency of the tank, especially when the edges have components that are parallel to the direction of Earth's gravity. Summary of the Invention

[0009] One concept upon which this invention is based is to propose a sealed and thermally insulated container with reduced convection. Specifically, one concept upon which this invention is based is to provide a sealed and thermally insulated container that restricts the presence of continuous circulation channels within a thermal insulation barrier, and more particularly, the presence of continuous circulation channels between the thermal insulation barrier and the sealing membrane, in order to limit natural convection within the thermal insulation barrier.

[0010] According to one embodiment, the present invention provides a sealed and thermally insulated tank for storing fluids, the tank comprising a thermal insulation barrier and a sealing membrane, the tank including a channel extending longitudinally along the sealing membrane, the channel being defined on one hand by the thermal insulation barrier and on the other hand by the outer surface of the sealing membrane, the thermal insulation barrier forming the bottom of the channel.

[0011] The tank also includes a shutter arranged in the channel, the shutter comprising a flexible membrane, the flexible membrane including a first fixing region and a second fixing region.

[0012] The first fixed region extends transversely to the longitudinal direction of the channel, and the first fixed region of the flexible membrane is fixed to the bottom of the channel.

[0013] The second fixing region extends laterally to the longitudinal direction of the channel, and the second fixing region is fixed to the outer surface of the sealing membrane that limits the channel.

[0014] The flexible membrane includes a closed portion extending from a first fixed region to a second fixed region, the closed portion extending across the channel between the bottom of the channel and the sealing membrane to generate head loss in the channel.

[0015] The phrase "fixed area extending transversely to the longitudinal direction of the channel" should be understood as referring to the area of ​​the flexible membrane that extends in a manner intersecting (secant) with the longitudinal direction of the channel, preferably at a right angle to the longitudinal direction of the channel.

[0016] These features reduce convection within the tank, and particularly within the channels. In effect, the closure allows for head loss in the flow that can occur within the channels while permitting gas circulation, such as inert gas circulation.

[0017] In practice, because the fixed area of ​​the flexible membrane is fixed to the bottom of the channel in a direction transverse to the longitudinal direction of the channel, and the second fixed area is fixed to the outer surface of the sealing membrane in a direction transverse to the longitudinal direction of the channel, the closing portion extends between the bottom of the channel and the outer surface of the sealing membrane, thereby allowing for good closure of the channel. Furthermore, since the second fixed area is fixed to the sealing membrane, it follows the deformation of the sealing membrane, ensuring that the closing portion remains even when the sealing membrane deforms. Moreover, this fixing of the first and second fixed areas allows for the simple removal of manufacturing and / or positioning tolerances of the thermal insulation barrier and / or the sealing membrane, while maintaining good closure of the channel.

[0018] According to an implementation, such a sealed and thermally insulated container may include one or more of the following features.

[0019] According to one embodiment, the first fixed region and the second fixed region are offset along the longitudinal direction of the channel. In other words, the first fixed region and the second fixed region are discontinuous, such that the closed portion extends with a component portion parallel to the longitudinal direction of the channel.

[0020] According to one embodiment, the closing portion is movable relative to the bottom of the channel. According to another embodiment, the closing portion is movable relative to the sealing membrane. In other words, according to one embodiment, the closing portion is free relative to the bottom of the channel and the sealing membrane. Therefore, the closing portion closes the channel in a non-sealing manner, and thus allows circulation of the inert gas in the channel while generating a pressure head loss in the flow.

[0021] According to one embodiment, the closure portion is deformable between the bottom of the channel and the sealing membrane. This deformability of the closure portion can be achieved in many ways. According to one embodiment, the flexible membrane is made of an elastically deformable material. According to one embodiment, when the closure portion is arranged in a plane, the length of the closure portion is greater than the distance between the surface used to fix the first fixing region to the bottom of the channel and the surface used to fix the second fixing region to the sealing membrane. In other words, according to one embodiment, the closure portion is in a relaxed state in the channel, particularly in a channel at ambient temperature.

[0022] According to one embodiment, the closure portion located between the bottom of the channel and the sealing film is deformable and includes at least one fold along an axis transverse to the longitudinal direction of the channel.

[0023] According to one embodiment, the first fixing region and the second fixing region are located at opposite ends of the flexible membrane and are arranged at the same level in the longitudinal direction of the channel.

[0024] The closure then has, for example, a U-shape, which is particularly advantageous and suitable for in-situ installation in a can. A tool can be used to install such a closure, for example, one designed to allow the closure to be inserted into the channel without damaging the closure's blades.

[0025] According to one embodiment, the closure includes a compressible element that is pre-pressed and accommodated in a fold between a first fixed region and a second fixed region to apply a reaction force that presses the first fixed region against the bottom of the channel and the second fixed region against the outer surface of the sealing film that limits the channel.

[0026] According to one embodiment, the compressible element is made of a material selected from cotton, felt, glass wool, rock wool, polymer foam, polyethylene cotton, etc., and extends along the thickness direction between the first fixing region and the second fixing region. This feature facilitates fixing by gluing.

[0027] According to one embodiment, an anti-adhesive film insert is inserted into the fold to prevent the two flat portions of the flexible film folded over each other from being glued together, for example, by any spillage of adhesive. The anti-adhesive film can be a sheet made of polyethylene or PTFE. According to one embodiment, the anti-adhesive film inserted into the fold includes an end located in the fold and a second end located outside the fold. This feature facilitates the installation of the closure in the can and prevents any spillage of adhesive that could disrupt the installation of the closure. The anti-adhesive film can be inserted alone or in combination with a compressible element. To facilitate the installation of the closure in the can, the anti-adhesive film and the flexible film can be folded continuously around the end edges of the blade to push the anti-adhesive film and the flexible film into the channel.

[0028] According to one embodiment, the closure includes two folds spaced apart from each other along the longitudinal direction of the channel, each fold being formed along an axis transverse to the longitudinal direction of the channel. A first fixing region and a second fixing region are located at opposite ends of the flexible membrane and offset along the longitudinal direction of the channel. The closure has, for example, a Z-shaped form.

[0029] According to one embodiment, the closure has an elongation direction extending between a first fixed region and a second fixed region. The flexible membrane is made of a woven material and includes threads oriented at 35° and 55° (degrees) relative to the elongation direction; preferably, the threads are oriented at 45° relative to the elongation direction. Through this feature, the closure achieves flexibility through the deformation of the weft and warp threads of the woven material.

[0030] These features allow the closure to follow changes in the relative positioning and dimensions of the thermal insulation barrier and / or sealing membrane while effectively closing the channel to generate head loss in the flow within the channel. In particular, this closure allows for effective closure of the channel even when the can is cooled, i.e., under conditions of thermal shrinkage of the sealing membrane and the thermal insulation barrier, and variations in the deviation between the first and second fixed areas.

[0031] According to one embodiment, the closed portion of the flexible membrane is a first closed portion, the flexible membrane includes a third fixed region extending transversely to the longitudinal direction of the channel, the third fixed region being fixed to the bottom of the channel, a second fixed region being placed between the first fixed region and the third fixed region, the flexible membrane including a second closed portion extending from the second fixed region to the third fixed region, the second closed portion extending transversely across the channel between the bottom of the channel and the sealing membrane to generate pressure head loss in the channel.

[0032] This type of closure allows for proper closure of the channel and thus allows for significant head loss in the flow.

[0033] According to one embodiment, the third fixed region is offset relative to the first and second fixed regions along the longitudinal direction of the channel.

[0034] According to one embodiment, the second closing portion is movable relative to the bottom of the channel.

[0035] According to one embodiment, the second closing portion is movable relative to the sealing membrane.

[0036] In other words, according to one embodiment, the second closing portion is free relative to the bottom of the channel and the sealing membrane. Therefore, the second closing portion closes the channel in a non-sealing manner, and thus allows inert gas to circulate within the channel while generating a pressure head loss in the flow.

[0037] According to one embodiment, the second closing portion is deformable between the bottom of the channel and the sealing membrane. This deformability of the second closing portion can be achieved in many ways, for example, in a manner similar to the example described above for the first closing portion.

[0038] According to one embodiment, the flexible membrane is made of a material selected from glass pads, polyethylene films, and / or polyamide films. As examples, the membrane can be: glass-based fabric, polyethylene fabric, polyamide fabric, polyimide fabric, polyetherimide fabric, and this list is not exhaustive. This material exhibits good cold resistance while maintaining flexibility, thereby allowing the flexible membrane to conform to the deformation of the sealing membrane.

[0039] According to one embodiment, the first fixed region extends in a plane intersecting the longitudinal direction of the channel.

[0040] According to one embodiment, the first fixed region extends in a plane perpendicular to the longitudinal direction of the channel.

[0041] According to one embodiment, the second fixed region extends in a plane intersecting the longitudinal direction of the channel.

[0042] According to one embodiment, the second fixed region extends in a plane perpendicular to the longitudinal direction of the channel.

[0043] This type of anchorage zone, which is arranged perpendicular to the longitudinal direction of the channel, allows the channel to be properly closed by one or more closed sections.

[0044] According to one embodiment, the first fixing region and / or the second fixing region are fixed by adhesive bonding. According to one embodiment, the can includes a double-sided adhesive tape disposed between the first fixing portion and the bottom of the channel to secure the first fixing portion to the bottom of the channel. According to one embodiment, the can includes a double-sided adhesive tape disposed between a sealing film and the second fixing region to secure the second fixing region to the sealing film. This adhesive tape allows for simple and quick fixing of the first and second fixing regions. Furthermore, this adhesive tape allows for simple fixing by simply applying or pressing a flexible film onto the adhesive tape or by simply applying or pressing the adhesive tape onto the flexible film.

[0045] According to one embodiment, the tank includes a plurality of closures arranged in the channel along its longitudinal direction. Therefore, the flow within the channel is controlled along the channel. Such closures may include one or more closures as described above, or may include all of the closures described above.

[0046] According to one embodiment, the closures of the plurality of closures are arranged in the channel at regular intervals.

[0047] According to one embodiment, the thermal insulation barrier forming the bottom of the channel includes, for example, a plurality of partition plates spaced regularly or irregularly, and a plurality of engagement regions located between the partition plates, for example, having a regular or irregular spacing between two engagement regions. Closures can be arranged facing the partition plates such that engagement regions at each end of the plates are located between the closures. For example, the closures are spaced apart from each other at intervals corresponding to the regular or irregular spacing of the engagement regions. In one embodiment, at least one closure is arranged facing each partition plate. Therefore, there is always at least one closure that blocks flow between two consecutive engagement regions.

[0048] According to one embodiment, the closures are arranged at irregular intervals.

[0049] According to one embodiment, a sealed and thermally insulated can includes a first can wall and a second can wall forming the edge of a thermal insulation barrier. The first can wall includes a first anchoring surface, and the second can wall forms a second anchoring surface. The bottom of a channel is formed by the thermal insulation barrier between the first and second anchoring surfaces, and the bottom of the channel forms the edge. A sealing membrane includes a corner sealing portion, which includes a first portion anchored to the first anchoring surface and a second portion anchored to the second anchoring surface. The corner sealing portion also includes a central portion disposed between the first and second portions, which is free relative to the thermal insulation barrier to absorb strain in the sealing membrane aligned with the edge through deformation. The channel is defined by the outer surface of the corner sealing portion.

[0050] According to one embodiment, the sealed and thermally insulated tank includes a corner structure comprising a first insulating plate and a second insulating plate. The first insulating plate forms the end of a thermal insulation barrier of a first tank wall, and the second insulating plate forms the end of a thermal insulation barrier of a second tank wall. The first and second insulating plates together form the edge.

[0051] The corner structure also includes a first sealing film portion and a second sealing film portion. The first sealing film portion rests against the first isolation plate and forms the end of the sealing film of the first tank wall. The second sealing film portion rests against the second isolation plate and forms the end of the sealing film of the second tank wall.

[0052] According to one embodiment, the first sealing film portion includes a first composite film fixed to a first insulating plate, and the second sealing film portion includes a second composite film fixed to a second insulating plate.

[0053] According to one embodiment, the first sealing film portion includes a laminated composite sealing film comprising a metal sheet disposed between two resin-impregnated fiber layers. According to one embodiment, the first sealing film portion is bonded to a first insulating plate. According to one embodiment, the second sealing film portion includes a laminated composite sealing film comprising a metal sheet disposed between two resin-impregnated fiber layers. According to one embodiment, the second sealing film portion is bonded to a second insulating plate.

[0054] According to one embodiment, the first sealing membrane portion is a metal plate anchored to the first thermal insulation barrier portion. According to one embodiment, the second sealing membrane portion is a metal plate anchored to the second thermal insulation barrier portion.

[0055] According to one embodiment, a first insulating plate forms a first anchoring surface. According to one embodiment, a second insulating plate forms a second anchoring surface.

[0056] According to one embodiment, a first sealing film portion, such as the edge of the first sealing film portion, forms a first anchoring surface. According to one embodiment, a second sealing film portion, such as the edge of the second sealing film portion, forms a second anchoring surface.

[0057] The corner seal can be fixed to the first anchoring surface and the second anchoring surface in various ways. According to one embodiment, the corner seal is glued to one or both of the first anchoring surface and the second anchoring surface. According to another embodiment, the corner seal is welded to one or both of the first anchoring surface and the second anchoring surface.

[0058] According to one embodiment, the corner sealing portion includes a composite flexible sealing membrane, for example, the corner sealing portion includes a laminated composite comprising a metal sheet disposed between two glass fiber layers.

[0059] According to one embodiment, the corner sealing part is a metal angle iron piece.

[0060] These features allow for the simple and rapid fabrication of sealed and thermally insulated can corners without the risk of creating any convection. Specifically, these features enable the use of metal angle irons or flexible sealing membranes to form a seal at the can corners, ensuring that no convection occurs at the corners and between the sealing membrane and the thermal barrier.

[0061] According to one embodiment, the sealed and thermally insulated can also include a filling block, the filling block including a first outer surface of a thermally insulated barrier abutting against a first can wall and a second outer surface of a thermally insulated barrier abutting against a second can wall, the filling block also including a concave inner surface, and the channel is defined by the inner surface of the filling block.

[0062] According to one embodiment, one end of the first fixing region and / or the second fixing region, preferably both opposite ends, overlaps with the channel to be positioned between the sealing film and the thermal insulation barrier. Therefore, fixing the first fixing region and / or the second fixing region is simple and reliable, with the ends clamped between the sealing film and the thermal insulation barrier.

[0063] According to one embodiment, one end of the first fixing region and / or the second fixing region, preferably two opposite ends, overlaps with the channel to be positioned between two consecutive portions of the sealing membrane, the two consecutive portions being tightly connected. Therefore, fixing of the first fixing region and / or the second fixing region is simple and reliable, with the ends clamped between the two consecutive portions of the sealing membrane.

[0064] According to one embodiment, the sealing film includes a corrugated portion protruding toward a thermal barrier extending in the longitudinal direction of the channel. The thermal barrier includes a groove in which the corrugated portion is accommodated, and the bottom of the channel is formed by the groove.

[0065] According to one embodiment, the sealed membrane includes a series of parallel corrugated portions and a flat portion, the flat portion being located between two adjacent parallel corrugated portions, the parallel corrugated portions protruding toward a thermal insulation barrier.

[0066] The thermal insulation barrier comprises a series of parallel grooves, with parallel corrugated portions accommodated in corresponding grooves.

[0067] The can also include multiple channels, each defined on one side by a corresponding groove and on the other by a sealing membrane, with the bottom of each channel formed by a corresponding groove.

[0068] The can also include multiple closure elements, each comprising a flexible membrane, the flexible membrane including a first fixing region and a second fixing region.

[0069] The first fixing region extends transversely to the longitudinal direction of the corresponding groove, and the first fixing region of the flexible membrane is fixed to the bottom of the corresponding channel.

[0070] The second fixing region extends laterally to the longitudinal direction of the channel, and the second fixing region is fixed to the outer surface of the sealing film that limits the channel.

[0071] The flexible membrane includes a closed portion extending from a first fixed region to a second fixed region, the closed portion extending across the channel between the bottom of the channel and the sealing membrane to generate a pressure head loss in the channel.

[0072] These features allow the corrugated portion of the corrugated sealing membrane to be accommodated within the grooves of the thermal insulation barrier without generating natural convection that would impair the insulation performance of the thermal insulation barrier.

[0073] According to one embodiment, the channel has a component that is parallel to the direction of Earth's gravity.

[0074] According to one implementation, the channel is parallel to the direction of Earth's gravity.

[0075] Such channels with vertical components are most likely to promote convection, making it particularly advantageous to place one or more closures in such channels and effectively reduce convection.

[0076] According to one embodiment, the channel has a component that is perpendicular to the direction of Earth's gravity.

[0077] According to one implementation, the channel is perpendicular to the direction of Earth's gravity.

[0078] These tanks can be integrated into onshore storage facilities, such as for storing LNG, or they can be installed in coastal or deep-water floating structures, particularly in methane tankers, floating storage and regasification units (FSRUs), and floating production and storage-offloading (FPSO) units. These tanks can also be used as fuel tanks in any type of vessel.

[0079] According to one embodiment, the present invention also provides a vessel for transporting cold liquid products, the vessel comprising a twin hull and the aforementioned tank disposed within the twin hull.

[0080] According to one embodiment, the present invention also provides a method for loading or unloading such a vessel, wherein cold liquid products are transported from a floating or shore-based storage facility to the vessel's tanks via insulated pipelines, or cold liquid products are transported from the vessel's tanks to a floating or shore-based storage facility via insulated pipelines.

[0081] According to one embodiment, the present invention also provides a transfer system for cold liquid products, the system comprising: the aforementioned vessel; an isolation pipeline arranged to connect tanks installed in the hull of the vessel to a floating or shore-based storage device; and a pump for driving a flow of cold liquid products from the floating or shore-based storage device via the isolation pipeline to the tanks of the vessel, or driving a flow of cold liquid products from the tanks of the vessel via the isolation pipeline to the floating or shore-based storage device. Attached Figure Description

[0082] The invention will be better understood from the following description of several specific embodiments of the invention, given in an illustrative and non-limiting manner with reference to the accompanying drawings, and other objects, details, features, and advantages of the invention will become more apparent.

[0083]

Figure 1

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Figure 2

【 Figure 1 A schematic perspective view of the corner structure of the can shown in the figure;

[0085]

Figure 3

[0086]

Figure 4

[0087]

Figure 5

[0088]

Figure 6

[0089]

Figure 7

【 Figure 5 A schematic diagram of a secondary sealing film and secondary thermal insulation barrier at the corner of a sealed and thermally insulated tank, as described in a variant embodiment.

[0090]

Figure 8

[0091]

Figure 9

[0092]

Figure 10

[0093]

Figure 11

[0094]

Figure 12

[0095] The terms “outer” and “inner” are typically used to refer to the interior and exterior of a container to define the relative position of one element with respect to another.

[0096] A sealed and thermally insulated tank for storing and transporting cryogenic fluids, such as liquefied natural gas (LNG), comprises multiple tank walls, each having a multi-layered structure.

[0097] The tank wall, from the outside to the inside, includes: a secondary thermal insulation barrier 1, which is anchored to a support structure 2 by a secondary retaining member (not shown); a secondary sealing membrane 3, which is supported by the secondary thermal insulation barrier 1; a primary thermal insulation barrier 4, which rests against the secondary sealing membrane 3; and a primary sealing membrane 5, which is supported by the primary thermal insulation barrier 4 and is used to contact the cryogenic fluid contained in the tank.

[0098] The support structure 2 can be, in particular, a self-supporting sheet of metal, or more generally, the support structure 2 can be, in particular, any type of rigid partition with suitable mechanical properties. The support structure 2 can be, in particular, formed from the hull or double hull of a ship, such as... Figure 1 As shown in the diagram, the support structure 2 includes multiple walls that define the overall form of the tank, typically a polyhedral form. Some tanks may also include only a single thermal insulation barrier and a single sealing membrane for storing LPG.

[0099] like Figure 1 As shown, the tank includes lateral tank walls 6 and transverse tank walls 7 (a single transverse wall in...). Figure 1 As shown in the diagram, the lateral tank wall 6 and the transverse tank wall 7 have vertical components, that is, components parallel to the direction of Earth's gravity. In such tank walls 6 and 7 with vertical components, the presence of channels extending along the entire height of the walls 6 and 7 may promote natural convection. In fact, thermosiphoning may occur in such walls 6 and 7, resulting in a reduction in the thermal insulation efficiency of the thermal insulation barriers 1 and 4. One aspect of the invention stems from the concept of limiting or even eliminating these natural convection phenomena.

[0100] At the junction between the first wall 8, such as the lateral wall 6, and the second wall 9, such as the transverse wall 7, the tank includes Figure 2 The corner structure 10 shown is advantageously prefabricated.

[0101] Figure 2The corner structure 10 shown includes a first corner secondary baffle 11 and a second corner secondary baffle 12. The corner secondary baffles have an outer rigid plate 13, a baffle liner 14, and an inner rigid plate 15 extending from the outside to the inside of the tank. The first corner secondary baffle 11 and the second corner secondary baffle 12 also have inclined surfaces, and the inclined surfaces of the two corner secondary baffles 11 and 12 are continuous. Therefore, as... Figure 3 As shown in detail, the corner secondary insulation plate forms the edge 16 of the secondary thermal insulation barrier 1.

[0102] The first corner secondary insulating plate 11 supports the first primary sealing film portion 17, and the second corner secondary insulating plate 12 supports the second primary sealing film portion 18. These first and second primary sealing film portions 17 and 18 can be manufactured in various ways. In one embodiment, the first and second primary sealing film portions 17 and 18 are made of laminated sealing films. This laminated sealing film comprises a metal sheet, for example made of aluminum, placed between two resin-impregnated fiber layers. These secondary sealing film portions 17 and 18, made of laminated sealing films, are, for example, glued to the inner surfaces of the corner secondary insulating plates 11 and 12. In another embodiment, the first and second primary sealing film portions 17 and 18 are metal plates anchored to the corner secondary insulating plates 11 and 12.

[0103] like Figure 3 As shown, the secondary sealing membrane portions 17 and 18 include longitudinal edges extending parallel to the edge 16 of the secondary thermal insulation barrier 1, said edges being arranged to be spaced apart from the edge 16. Typically, the first primary sealing membrane portion 17 forms the end of the secondary sealing membrane 3 of the first wall 8, and the second secondary sealing membrane portion 18 forms the end of the secondary sealing membrane 3 of the second wall 9.

[0104] To ensure a seal of the secondary sealing membrane 3 at the corner of the tank, the corner structure 10 includes a corner secondary sealing membrane portion 19. This corner secondary sealing membrane portion 19 tightly connects the primary sealing membrane portion 17 and the secondary sealing membrane portion 18. This corner secondary sealing membrane portion can be manufactured in many ways. In one embodiment, the corner secondary sealing membrane portion 19 is formed as a laminated sealing membrane, for example, comprising a metal sheet placed between two unresin-impregnated fiber layers. This corner secondary sealing membrane portion 19, made of the laminated sealing membrane, is, for example, glued to the primary sealing membrane portion 17 and the secondary sealing membrane portion 18.

[0105] According to another embodiment, the corner secondary sealing membrane portion 19 is formed by a metal angle iron piece tightly anchored to the primary sealing membrane portion 17 and the secondary sealing membrane portion 18.

[0106] like Figure 3 As shown in detail, the corner secondary sealing membrane portion 19 extends along edge 16. The corner secondary sealing membrane portion 19 has a longitudinal edge parallel to edge 16. The first longitudinal edge of the corner secondary sealing membrane portion 19 forms a first anchoring region 20, which is formed by… Figure 3 The dashed lines in the diagram show that the first anchoring region 20 is tightly secured to the first primary sealing membrane portion 17. Similarly, the second longitudinal edge of the corner secondary sealing membrane portion 19 forms a second anchoring region 21, which is formed by... Figure 3 The dashed line in the diagram shows that the second anchoring area 21 is tightly fixed to the second-stage sealing membrane portion 18.

[0107] The tight fastening of the anchoring areas 20, 21 of the corner secondary sealing membrane portion 19 to the secondary sealing membrane portions 17, 18 can be performed in various ways. For example, if the corner secondary sealing membrane portion 19 is in the form of a laminated sealing membrane, the tight fastening of the anchoring areas 20, 21 of the corner secondary sealing membrane portion 19 to the secondary sealing membrane portions 17, 18 can be performed by gluing. Or even if the corner secondary sealing membrane portion 19 is in the form of a metal angle iron, the tight fastening of the anchoring areas 20, 21 of the corner secondary sealing membrane portion 19 to the secondary sealing membrane portions 17, 18 can be performed by welding. The internal rigid plate 15 of the corner secondary insulating plates 11, 12 may include a heat-protective strip accommodated in a countersunk hole to protect the corner secondary insulating plates 11, 12 during such welding.

[0108] The corner structure 10 also includes a plurality of primary insulating elements 22, which are juxtaposed along the edge 16 of the secondary thermal barrier 1. Each primary insulating element 22 includes: a first primary insulating block 23 resting on the first primary sealing membrane portion 17; and a second primary insulating block 24 resting on the second primary sealing membrane portion 18. The plurality of primary insulating elements 22 form the primary thermal barrier 4.

[0109] The primary sealing membrane 5 includes a plurality of metal corner brackets 25, each of which rests against a corresponding primary insulating block 23, 24. Therefore, each metal corner bracket includes: a first wing-shaped portion 26 resting against a first primary insulating block 23 of the primary insulating element 22; and a second wing-shaped portion 27 resting against a second primary insulating block 24 of the primary insulating element 22.

[0110] The corner secondary sealing membrane portion 19 includes a central region 28 positioned between the first anchoring region 20 and the second anchoring region 21. This central region 28 is arranged to align with and extend along the edge 16. This central region 28 is not fixed to the secondary thermal insulation barrier 1. In other words, the central region 28 is free with respect to the secondary thermal insulation barrier 1, and more specifically, it is free with respect to the edge 16. Further details and features of this corner structure are described, for example, in document WO2014167214A2.

[0111] The central region 28 of the corner secondary sealing membrane portion 19 is not fixed to the secondary thermal insulation barrier 1, allowing for the absorption of strain experienced by the secondary sealing membrane 3 aligned with the edge 16. In fact, as... Figure 4 As shown, when constructing the tank, the corner secondary sealing membrane portion 19 is arranged such that the central region 28 is as close as possible to the edge 16. This arrangement allows for the limitation of the existence of convection-promoting gaps between the secondary sealing membrane 3 and the secondary thermal insulation barrier 1.

[0112] However, when the can is cooled, the secondary sealing membrane 3 and therefore the corner secondary sealing membrane portion 19 contract, thereby causing deformation through the tension of the corner secondary sealing membrane portion 19, such as Figure 5 As shown in the diagram. Similarly, the corner secondary insulating plates 11, 12 contract, thereby separating the anchoring areas 20, 21 of the corner secondary sealing membrane portion 19 from each other and thus also causing deformation by the tension of the corner secondary sealing membrane portion 19.

[0113] like Figure 5 As shown, the deformation caused by the tension of the corner secondary sealing film portion 19 separates the central region 28 from the edge 16, thereby significantly increasing the volume of the gap between the corner secondary sealing film portion 19 and the secondary thermal insulation barrier 1. Therefore, a channel 29 is formed between the secondary sealing film 3 and the secondary thermal insulation barrier 1, or the channel 29 between the secondary sealing film 3 and the secondary thermal insulation barrier 1 is enlarged. This channel 29 extends along the entire length of the edge 16 and has a longitudinal direction parallel to the edge 16. Typically, this channel is formed by the outer surface of the central portion 28 of the corner secondary sealing film portion 19 and a portion of the inner surface of the rigid plate 15 of the corner secondary insulation plates 11, 12, including the portion between the edge 16 and the first and second secondary sealing film portions 17 and 18, the portion of the inner surface of the rigid plate 15 forming the bottom 36 of the channel 29.

[0114] To prevent convection in channel 29, the tank includes a closure 30. This closure is arranged in channel 29 and between the inner surface of the secondary thermal insulation barrier 1 and the outer surface of the secondary sealing membrane 3.

[0115] Figure 6 An exemplary embodiment of this closure 30 is shown. The closure 30 is formed in the form of a flexible membrane, for example, the flexible membrane has a polygonal shape.

[0116] Closure 30 may be manufactured using one of the materials cited below or a combination of multiple materials from the following: thermoplastic materials, including polyethylene (PE), polyethylene terephthalate (PET), polyamide, polyimide, polyetherimide, polypropylene, which may be in the form of a woven or non-woven film or any other material or fabric that exhibits flexibility upon cooling. Closure 30 may also be formed as a woven fabric, possibly a coated woven fabric. The woven fabric may be based on different types of fibers, such as mineral fibers, like glass fiber, basalt fiber, or natural fibers, such as hemp fiber, flax fiber, or wool fiber, or thermoplastic fibers (PE, PET, PP, PI, PEI, etc.).

[0117] Figure 6 The flexible membrane 30 shown includes a first fixing region 31, a second fixing region 32, and a third fixing region 33. The first fixing region 31 and the third fixing region 33 are formed at opposite ends of the flexible membrane 30. These first fixing regions 31 and the third fixing regions 33 are formed, for example, by opposite lateral edges of the flexible membrane 30.

[0118] The second fixed region 32 is positioned between the first fixed region 31 and the third fixed region 33, and for example, the distance between the second fixed region 32 and the distance between the third fixed region 33 are equal.

[0119] The flexible membrane 30 also includes a first closed portion 34 disposed between the first fixed region 31 and the second fixed region 32, and a second closed portion 35 disposed between the second fixed region 32 and the third fixed region 33.

[0120] The first fixed region 31 and the third fixed region 33 are fixed to the secondary thermal insulation barrier 1. More specifically, the first fixed region 31 and the third fixed region 33 are fixed to the bottom 36 of the channel 29 and extend laterally to the longitudinal direction of the channel 29; preferably, the first fixed region 31 and the third fixed region 33 are fixed to the bottom 36 of the channel 29 and extend perpendicularly to the longitudinal direction of the channel 29.

[0121] This fixation of the first fixing region 31 and the third fixing region 33 to the bottom 36 of the channel 29 can be performed in a variety of ways. For example, this fixation is formed by gluing or double-sided adhesive tape comprising, for example, polytetrafluoroethylene (PTFE) and placed between each of the first fixing region 31 and the third fixing region 33 and the bottom 36 of the channel 29.

[0122] The second fixing region 32 is fixed to the outer surface of the central portion 28 of the corner secondary sealing film portion 19. Similar to the fixing methods of the first fixing region 31 and the third fixing region 33, the fixing of the second fixing region 32 can be performed in various ways, such as by gluing or by using double-sided adhesive tape placed between the second fixing region 32 and the outer surface of the central region 28 of the corner secondary sealing film portion 19.

[0123] According to one embodiment, installing the flexible membrane 30 in the tank includes: firstly, fixing a first fixing region 31 and a third fixing region 33 to the bottom 36 of the channel 29 by gluing or by adhesive tape. Furthermore, double-sided adhesive tape is applied to the outer surface of the central portion 28 of the corner secondary sealing membrane portion 19 at the location where the second fixing region 32 must be fixed. Next, the corner secondary sealing membrane portion 19, to which the double-sided adhesive tape is provided, is anchored to the first primary sealing membrane portion 17 and the second primary sealing membrane portion 18. Anchoring the corner secondary sealing membrane portion to the secondary sealing membrane portions 17 and 18 causes the double-sided adhesive tape to abut against the second fixing region 32, thus fixing the second fixing region 32 to the corner secondary sealing membrane portion 19. When the corner secondary sealing membrane portion is made of a laminated sealing membrane, the pressure applied to the inner surface of the laminated sealing membrane aligned with the double-sided adhesive tape can enhance the fixation of the second fixing region 32 to the laminated sealing membrane.

[0124] The first closing portion 34 and the second closing portion 35 are free with respect to the secondary thermal insulation barrier 1 and the secondary sealing membrane 3. In other words, the first closing portion 34 and the second closing portion 35 are neither fixed to the secondary thermal insulation barrier 1 nor to the secondary sealing membrane 3. Therefore, the longitudinal edges 37 of the closing portions 34 and 35 are relaxed, and on the one hand, the longitudinal edges 37 of the closing portions 34 and 35 allow for reduced gas circulation in the channel 29, that is, allow for pressure head loss associated with the arrangement of the closing portions 34 and 35 in the channel 29; on the other hand, the longitudinal edges 37 of the closing portions 34 and 35 allow for deformation of the flexible membrane 30 accompanied by deformation caused by tensioning of the corner secondary sealing membrane portion 19.

[0125] In fact, as described above and with reference to the accompanying drawings, when the tank is cooled, the corner secondary sealing membrane portion 19 tensions. During this tensioning of the corner secondary sealing membrane portion 19, the second fixed region 32 of the flexible membrane 30, fixed to the central region 28 of the corner secondary sealing membrane portion 19, undergoes a change in the position of the central region 28 associated with the deformation of the corner secondary sealing membrane portion 19. Since the first fixed region 31 and the third fixed region 33 of the flexible membrane 30 are fixed to the secondary thermal insulation barrier 1, the closing portions 34 and 35 of the flexible membrane 30 are tensioned between the fixed regions 31, 32, and 33, and the closing portions 34 and 35 of the flexible membrane 30 extend in the channel 29 between the secondary thermal insulation barrier 1 and the secondary sealing membrane 3. Therefore, the channel 29 is closed by the first closing portion 34 and the second closing portion 35 located between the central region 28 of the corner secondary sealing membrane portion 19 and the secondary thermal insulation barrier 1, while allowing gas circulation and having a head loss in the flow.

[0126] When the flexible membrane 30 exhibits good flexibility upon cooling, it promotes a change in the position of the second fixed region 32 accompanying the corner secondary sealing membrane portion 19. Therefore, as... Figure 6 As shown, when the can is cooled, the closed portions 34 and 35 can deform slightly and take on a conical shape.

[0127] Such closures 30 are advantageously arranged inside the can and at its corners, with the edge 16 of the can typically having a portion parallel to Earth's gravity between the lateral wall 6 and the transverse wall 7. Such closures 30 can also be arranged inside the can and at its corners, with the edge 16 perpendicular to Earth's gravity. Furthermore, multiple closures 30 can be arranged along the channel 29, for example, at regular intervals, thereby controlling pressure head loss along the entire channel 29.

[0128] Figure 7 An embodiment is shown in which the corner secondary sealing membrane portion 19 is formed of a laminated sealing membrane bonded to the primary sealing membrane portion 17 and the secondary sealing membrane portion 18, and the can also include a positioning filler block 38 for the corner secondary sealing membrane portion 19.

[0129] The filler block 38 is arranged along the edge 16 on the bottom 36 of the channel 29, and the filler block 38 has a first surface 39 and a second surface 40 resting on the inner rigid plate 15 of the corner secondary partition. The filler block 38 also includes an inner surface 41 connecting the first surface 39 and the second surface 40 of the filler block 38. The inner surface 41 has a concave shape, and the concavity of the inner surface 41 changes towards the inside of the tank.

[0130] When the corner secondary sealing membrane portion 19 is installed, the central region 28 of the corner secondary sealing membrane portion 19 is arranged to rest against the inner surface 41 of the filler block 38. Therefore, the corner secondary sealing membrane portion 19 is easily positioned to glue the first fixing region 20 and the second fixing region 21 to the first primary sealing membrane portion 17 and the second primary sealing membrane portion 18, respectively.

[0131] Therefore, when the corner secondary sealing membrane portion 19 is glued, typically during can manufacturing, this filler block 38 allows for control of the radius of curvature of the central region 28 of the corner secondary sealing membrane portion 19. This filler block 38 also allows for a reduction in the size of the channel 29, but does not prevent the channel 29 from expanding during can cooling, as by… Figure 7 The corner secondary sealing membrane portion 19 shown is represented in a tensioned state associated with heat shrinkage. In this channel 29, the inner surface 41 subsequently forms the bottom 36 of the channel 29.

[0132] With the presence of this filler block 38, the first fixing region 31 and the third fixing region 33 of the closure 30 can be directly fixed to the inner surface 41 of the filler block 38.

[0133] In one embodiment, the first ends of one or more of the fixing regions 31, 32, and / or 33 of the flexible membrane 30 are positioned between the first sealing membrane portion 17 and the first anchoring region 20 of the corner secondary sealing membrane portion 19. Similarly, the second ends of one or more fixing regions 31, 32, and / or 33 are positioned between the second secondary sealing membrane portion 18 and the second anchoring region 21 of the corner secondary sealing membrane portion 19. Typically, these ends of the fixing regions 31, 32, and / or 33 are thus sandwiched between the first secondary sealing membrane portion 17 and the second secondary sealing membrane portion 18 and the corner secondary sealing membrane portion 19, thereby ensuring that the fixing regions 31, 32, and / or 33 are secured in a simple manner.

[0134] Figure 8 A portion of a secondary thermal insulation barrier 1 is shown, on which a corrugated secondary sealing film 3 with outwardly facing corrugated portions is placed. The secondary sealing film 3 is shown in a transparent manner. In this figure, [the following is related to the above...] Figures 1 to 7 The described components are the same as or perform the same as those mentioned above. Figures 1 to 7 Elements that have the same function as those described are shown with the same reference numerals increased by 100.

[0135] The secondary thermal insulation barrier 101 of the tank wall includes a plurality of secondary insulation plates in the form of parallelepipeds, which are juxtaposed according to a regular mesh pattern. In a manner similar to the first and second plates 11, 12 described above, these secondary insulation plates include an outer rigid plate (not shown), an insulation liner 43, and an inner rigid plate 44.

[0136] Furthermore, the inner surface of the insulating plate includes a plurality of grooves 45, which are formed in the inner rigid plate 44 and may also be formed on the inner surface of the insulating liner 43. These grooves 45 allow for the accommodating of the corrugated portion 46 of the secondary sealing membrane 103, a portion of which is formed by… Figure 8 The dashed lines in the text represent this.

[0137] However, the dimensions of the groove 45 are configured to manage the manufacturing and positioning tolerances of the corrugated portion 46 of the secondary insulating plate and the secondary sealing membrane 103. In other words, when the corrugated portion 46 is accommodated in the groove 45, a gap exists in the groove 45 and between the corrugated portion 46 and the secondary thermal insulation barrier 101 formed by the secondary insulating plate. This gap between the corrugated portion 46 and the secondary thermal insulation barrier 101, in a manner similar to the corner between the two can walls of a can as described above, can potentially cause thermosiphoning, thereby reducing the insulation efficiency of the secondary thermal insulation barrier 101.

[0138] To avoid thermal siphoning in the groove 45, a closure 130 can be placed between the secondary sealing film 103 and the secondary thermal insulation barrier 101, and within the groove 45 of the secondary thermal insulation barrier 101. This closure 130 is similar to the one described above. Figure 6 The difference in the described closure 130 is that it includes only a first fixing region 131 and a second fixing region 132. The first fixing region 131 is fixed to the bottom 136 of the channel 129 formed by the groove 45 of the secondary thermal insulation barrier 101. The second fixing region 132 is fixed to the outer surface of the secondary sealing film 103, and the second fixing region 132 adheres to the outer surface of the corrugated portion 46 and a flat area adjacent to the corrugated portion 46 and arranged aligned with the groove 45.

[0139] Preferably, the first fixing region 131 and the second fixing region 132 extend a distance perpendicular to the direction of the groove 45 by a distance greater than the width obtained along the direction perpendicular to the longitudinal direction of the groove 45. In other words, in a manner similar to the description given above, the first and second ends of the first fixing region 131 and the second fixing region 132 are positioned between the flat portion of the secondary sealing membrane 103 and the inner surface of the rigid plate 44, on which the flat surface of the secondary sealing membrane 103 rests. Therefore, the first fixing region 131 and the second fixing region 132 are fixed only between the secondary sealing membrane 103 and the secondary thermal insulation barrier 101.

[0140] In an embodiment not shown, the closure 130 is arranged in the channel 129 and at the periphery of the inner surface of the insulating plate forming the secondary thermal insulation barrier 1. Therefore, when the closure 130 is initially secured to the bottom 136 of the channel 129, the application of the second securing region 132 to the inner surface of the secondary sealing membrane 103 is facilitated by simply touching the closure from the edge of the secondary insulating plate via the groove 45. In a variation of this embodiment, the lateral surface of the secondary insulating plate and the bottom 136 of the channel are glued together at the lateral surface before positioning the sealing membrane and the closure 130. The second securing region 132 of the closure 130 is initially secured to the outer surface of the secondary sealing membrane 103. Subsequently, the secondary sealing membrane 103 is added to the secondary insulating plate such that the flexible membrane forming the closure 130 extends beyond the lateral surface of the secondary insulating plate. Therefore, the overlapping portion of the membrane can be easily applied to the side surface of the secondary insulating plate and the bottom 136 of the channel 129 to secure the first fixing region 131 to the secondary insulating plate.

[0141] exist Figure 9 and Figure 10 In the illustrated embodiment, the closure 330 includes a first fixing region 331 and a second fixing region 332. The first fixing region 331 and the second fixing region 332 are formed at opposite ends of the flexible membrane. The first fixing region 331 is fixed to the bottom 236 of the channel 329. The second fixing region 332 is fixed to the outer surface of the sealing membrane 203. The first fixing region 331 and the second fixing region 332 are offset along the longitudinal direction of the channel 329. In other words, the first fixing region and the second fixing region are not facing each other, such that the closure portion 235 extends a portion of the structure parallel to the longitudinal direction of the channel 329. The closure portion 235 includes two folds spaced approximately half a circle apart from each other and thus has a Z-like shape.

[0142] To facilitate integration of the closure into the can, the closure 330 can be installed by prefabricating it in the corner structure 10 before placing the corner structure 10 into the sealed and insulated can. The structure of the closure 330 is easier to install when the panel, which is partially covered by a sealing membrane, is prefabricated in the factory.

[0143] exist Figure 11 In the illustrated embodiment, the closure 230 is thus formed as a flexible membrane folded about an axis transverse to the longitudinal direction of the channel, and the flexible membrane is substantially U-shaped. The closure 230 includes a first fixing region 231, a second fixing region 232, and a self-folded closing portion 135. The first fixing region 231 and the second fixing region 232 are formed at opposite ends of the flexible membrane. The first fixing region 231 is fixed to the bottom 236 of the channel. The second fixing region 232 is fixed to the outer surface of the sealing membrane 203. The first fixing region 231 and the second fixing region 232 face each other. When the closing portion is arranged in a plane, the flexible membrane has a length greater than the distance between the fixing surface of the first fixing region 231 fixed to the bottom of the channel 229 and the fixing surface of the second fixing region 232 fixed to the sealing membrane.

[0144] A flexible membrane forms a folded member. According to one embodiment, a compressible element 99 is housed within the folded member. This compressible element 99 is formed, for example, from cotton, felt, glass wool, rock wool, or polymer foam. The compressible element 99 is compressed between a first fixing region 231 and a second fixing region 232, and thus exerts a reaction force that promotes the first fixing region 231 and the second fixing region 232 to be respectively glued and fixed to the bottom of the channel and the outer surface of the sealing membrane. A closure 230 is inserted into a sealed and heat-insulated container and into the gap between the bottom of the channel 229 and the sealing membrane.

[0145] According to one embodiment, in place of or in combination with the compressible element 99, an anti-adhesion film (not shown) – which prevents two portions of the flexible film folded relative to each other from being glued together – is inserted into the fold of the flexible film.

[0146] To install the closure 230 in the channel 229, a blade-shaped tool can be used; where applicable, a tool in the form of a flexible blade can be used, the curvature of which corresponds to the shape of the bottom of the channel, for example, to the filler block 38. Figure 7 The curvature of the anti-adhesion membrane and the flexible membrane is continuously folded around the end edge of the blade to push the anti-adhesion membrane and the flexible membrane into the channel 29 or 229, for example, between the filler block 38 and the corner secondary sealing membrane portion 19.

[0147] According to another embodiment, a special tool can be used to position the closure. This tool includes at least one blade and a handle that allows manipulation of the tool; the blade is for insertion between the two folds of the closure. It should be noted that... Figure 11 The structure of the closure 230 shown is advantageous because it makes it particularly suitable for in-situ installation inside the can when the can is assembled, and for placement when the plate covered by a portion of the sealing film is prefabricated in the factory.

[0148] The aforementioned technology for producing sealed and thermally insulated tanks can be used for different types of containers, such as to limit the presence of continuous circulation channels in the thermal insulation barrier of LNG containers located in onshore installations or floating structures, such as methane tankers.

[0149] Reference Figure 12 A cross-sectional view of the methane tanker 70 shows a generally prismatic, sealed, and thermally insulated tank 71 installed in the vessel's twin hulls 72. The walls of tank 71 include: a primary sealing barrier for contact with the LNG contained within the tank; a secondary sealing barrier disposed between the primary sealing barrier and the vessel's twin hulls 72; and two insulating barriers disposed between the primary and secondary sealing barriers and between the secondary sealing barriers and the twin hulls 72, respectively.

[0150] As is known to the public, the loading / unloading pipeline 73, located on the top deck of the vessel, can be connected to a sea or port terminal by means of suitable connectors to transfer LNG cargo from or to tank 71.

[0151] Figure 12 An example of an offshore terminal is shown, comprising a loading and unloading station 75, an underwater pipeline 76, and a shore-based facility 77. The loading and unloading station 75 is a fixed offshore facility, comprising a movable boom 74 and a lifting device 78 supporting the movable boom 74. The movable boom 74 is supported by a bundle of isolated flexible tubing 79 that can be connected to the loading / unloading pipeline 73. The directional movable boom 74 is adapted to templates for all methane tankers. Connecting lines (not shown) extend within the lifting device 78. The loading and unloading station 75 allows loading of a methane tanker 70 from the shore-based facility 77 or unloading of the methane tanker 70 to the shore-based facility 77. The shore-based facility 77 includes a liquefied gas storage tank 80 and a connecting line 81 connected to the loading or unloading station 75 via the underwater pipeline 76. The subsea pipeline 76 allows liquefied gas to be transferred over a considerable distance, such as 5 km, between the loading or unloading station 75 and the shore-based installation 77, which enables the methane tanker vessel 70 to be kept at a greater distance from the coast during loading and unloading operations.

[0152] In order to generate the pressure required to transfer liquefied gas, pumps embedded in the vessel 70 and / or pumps equipped in the shore-based equipment 77 and / or pumps equipped in the loading and unloading station 75 are implemented.

[0153] Although the invention has been described in conjunction with several specific embodiments, it is quite obvious that the invention is by no means limited to these embodiments, and the invention includes all technical equivalents of the above-described solutions and combinations thereof, as long as these solutions and combinations fall within the scope of the invention as defined by the claims.

[0154] In particular, the above description, made with reference to the accompanying drawings, is given in the context of a secondary thermal barrier on which a secondary sealing membrane rests; however, this description can also be applied to channels extending between a primary thermal barrier and a primary sealing membrane, or even in the context of a can comprising only a single thermal barrier and a single sealing membrane. Similarly, the closure described above can be arranged in a channel formed by the internal space of the corrugated portion of the sealing membrane. For example, such a closure can be arranged below the corrugated portion of the secondary sealing membrane protruding toward the interior of the can. Therefore, such a closure can be arranged in any channel in which thermosiphon convection may occur in a sealed and thermally insulated can.

[0155] Similarly, the embodiment shown in the accompanying drawings illustrates a closure comprising: one or two fixed regions that cooperate with a thermal insulation barrier; and a fixed region that cooperates with a secondary sealing membrane, although the number of fixed regions that can cooperate with the sealing membrane and the number of fixed regions that can cooperate with the thermal insulation barrier may differ. Thus, the closure may include multiple fixed regions for cooperating with the thermal insulation barrier and, alternatively, multiple fixed regions for cooperating with the sealing membrane, such that a closure portion between the fixed regions on the thermal insulation barrier and the fixed regions on the sealing membrane extends in the channel to block the channel.

[0156] The use of the verbs “comprising” or “including” and their variations does not exclude the presence of elements or steps other than those listed in the claims.

[0157] In the claims, any reference numerals between parentheses shall not be construed as limiting the claims.

Claims

1. A sealed and thermally insulated container for storing a fluid, the container comprising a thermal barrier and a sealing membrane, the container including a channel extending longitudinally along the sealing membrane, the channel being defined on one side by the thermal barrier and on the other side by an outer surface of the sealing membrane, the thermal barrier forming the bottom of the channel. The tank also includes a closure element disposed in the channel, the closure element comprising a flexible membrane, the flexible membrane comprising a first fixing region and a second fixing region. The first fixing region extends transversely to the longitudinal direction of the channel, and the first fixing region of the flexible membrane is fixed to the bottom of the channel. The second fixing region extends transversely to the longitudinal direction of the channel, and the second fixing region is fixed to the outer surface of the sealing film that defines the channel. The flexible membrane includes a closed portion extending from the first fixed region to the second fixed region, the closed portion extending across the entire width of the channel between the bottom of the channel and the sealing membrane to generate head loss in the channel.

2. The sealed and thermally insulated tank for storing fluids according to claim 1, wherein, The closed portion of the flexible membrane is a first closed portion. The flexible membrane includes a third fixed region extending transversely to the longitudinal direction of the channel, the third fixed region being fixed to the bottom of the channel. A second fixed region is positioned between the first fixed region and the third fixed region. The flexible membrane includes a second closed portion extending from the second fixed region to the third fixed region. The second closed portion extends across the channel between the bottom of the channel and the sealing membrane to generate a pressure head loss in the channel.

3. The sealed and thermally insulated tank for storing fluids according to claim 1, wherein, The closed portion is deformable, and the closed portion includes at least one fold along an axis transverse to the longitudinal direction of the channel.

4. The sealed and thermally insulated tank for storing fluids according to claim 3, wherein, The first fixing region and the second fixing region are located at opposite ends of the flexible membrane and are positioned at the same level in the longitudinal direction of the channel.

5. The sealed and thermally insulated tank for storing fluids according to claim 3, wherein, The closed portion includes two folds spaced apart from each other in the longitudinal direction of the channel, each fold being formed along an axis transverse to the longitudinal direction of the channel, the first fixing region and the second fixing region being located at opposite ends of the flexible membrane and offset in the longitudinal direction of the channel.

6. A sealed and thermally insulated tank for storing fluids according to any one of claims 1 to 5, wherein, The flexible membrane is made of a material selected from the following: glass pad, polyethylene film and / or polyamide film.

7. A sealed and thermally insulated tank for storing fluids according to any one of claims 1 to 5, wherein, The first fixed region and / or the second fixed region extend in a plane that intersects the longitudinal direction of the channel.

8. A sealed and thermally insulated tank for storing fluids according to any one of claims 1 to 5, wherein, The can includes a plurality of closures arranged in the channel along the longitudinal direction of the channel.

9. The sealed and thermally insulated tank for storing fluids according to claim 8, wherein, The closures of the plurality of closures are arranged at regular intervals in the channel along the longitudinal direction of the channel.

10. The sealed and thermally insulated tank for storing fluids according to claim 8, wherein, The thermal insulation barrier forming the bottom of the channel includes a plurality of spaced-apart partitions and a plurality of engagement regions located between the partitions, and the closures are arranged facing the partitions such that the engagement regions at each end of the partitions are located between the closures.

11. A sealed and thermally insulated tank for storing fluids according to any one of claims 1 to 5, wherein, The can includes a first can wall and a second can wall, the first can wall and the second can wall forming the edge of the thermal insulation barrier, the first can wall including a first anchoring surface and the second can wall forming a second anchoring surface, the bottom of the channel being formed by the thermal insulation barrier between the first anchoring surface and the second anchoring surface, the bottom of the channel forming the edge, and wherein the sealing membrane includes a corner sealing portion, the corner sealing portion including a first portion anchored to the first anchoring surface and a second portion anchored to the second anchoring surface, the corner sealing portion further including a central portion disposed between the first portion and the second portion, the central portion being free relative to the thermal insulation barrier, thereby absorbing strain in the sealing membrane aligned with the edge by deformation, the channel being defined by the outer surface of the corner sealing portion.

12. The sealed and thermally insulated tank for storing fluids according to claim 11, wherein, The tank includes a corner structure, which comprises a first insulating plate and a second insulating plate. The first insulating plate forms the end of a thermal insulation barrier on the first tank wall, and the second insulating plate forms the end of a thermal insulation barrier on the second tank wall. The first and second insulating plates together form the edge. The corner structure further includes a first sealing film portion and a second sealing film portion. The first sealing film portion rests against the first isolation plate and forms the end of the sealing film of the first tank wall. The second sealing film portion rests against the second isolation plate and forms the end of the sealing film of the second tank wall.

13. The sealed and thermally insulated tank for storing fluids according to claim 11, wherein, The tank also includes a filling block, which includes a first outer surface of a thermal insulation barrier abutting against the first tank wall and a second outer surface of a thermal insulation barrier abutting against the second tank wall. The filling block also includes a concave inner surface, and the channel is defined by the inner surface of the filling block.

14. A sealed and thermally insulated tank for storing fluids according to any one of claims 1 to 5, wherein, The sealing membrane includes a corrugated portion that protrudes toward the thermal barrier and extends along the longitudinal direction of the channel. The thermal barrier includes a groove in which the corrugated portion is accommodated, and the bottom of the channel is formed by the groove.

15. A sealed and thermally insulated tank for storing fluids according to any one of claims 1 to 5, wherein, The sealing membrane includes a series of parallel corrugated portions and flat portions, the flat portions being located between two adjacent parallel corrugated portions, the parallel corrugated portions protruding toward the thermal insulation barrier. The thermal insulation barrier includes a series of parallel grooves, with each of the parallel corrugated portions being accommodated in a corresponding groove. The can also include multiple channels, each channel being defined on one side by a corresponding groove and on the other side by a sealing membrane, the bottom of each channel being formed by a corresponding groove. The tank also includes multiple closure components, each comprising a flexible membrane, which includes a first fixing region and a second fixing region. The first fixing region extends transversely to the longitudinal direction of the corresponding groove, and the first fixing region of the flexible membrane is fixed to the bottom of the corresponding channel. The second fixing region extends transversely to the longitudinal direction of the channel, and the second fixing region is fixed to the outer surface of the sealing film that defines the channel. The flexible membrane includes a closed portion extending from the first fixed region to the second fixed region, the closed portion extending across the channel between the bottom of the channel and the sealing membrane to generate a pressure head loss in the channel.

16. A sealed and thermally insulated tank for storing fluids according to any one of claims 1 to 5, wherein, The channel has a component that is parallel to the direction of Earth's gravity or a component that is perpendicular to the direction of Earth's gravity.

17. A vessel for transporting cold liquid products, the vessel comprising a catamaran and a sealed and thermally insulated tank for storing fluids according to any one of claims 1 to 16 disposed in the catamaran.

18. A transfer system for a cold liquid product, the transfer system comprising: The vessel for transporting cold liquid products according to claim 17; Isolation pipelines are arranged to connect tanks installed in the twin hulls of the vessel to floating or shore-based storage devices. And a pump for driving a stream of cold liquid product from the floating or shore storage unit via the isolation line to the tank of the vessel, or driving a stream of cold liquid product from the tank of the vessel via the isolation line to the floating or shore storage unit.

19. A method for loading or unloading a vessel for transporting cold liquid products according to claim 17, wherein, Cold liquid products are transported from floating or shore storage facilities to the vessel's tanks via insulated pipelines, or cold liquid products are transported from the vessel's tanks to the floating or shore storage facilities via insulated pipelines.

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