Liquefied gas storage facility

Abstract

The invention relates to a liquefied gas storage installation (1), said tank (71) comprising a top wall (4) which is locally interrupted to delimit a loading / unloading opening (7), wherein a secondary insulating block (14) comprises a terminal secondary insulating block (34) adjacent to said loading / unloading opening (7), wherein said storage installation comprises at least two fixed supports (26) fixed to said upper support wall (8) and located on either side of said terminal insulating block (34), said secondary thermal barrier comprising a secondary stop plate arranged on said terminal secondary insulating block (34), wherein said secondary stop plate and said secondary cap (29) form a flat support surface for said secondary sealing membrane (11), and wherein said secondary sealing membrane (11) is fixed to said secondary cap (29) of said two fixed supports (26) on the one hand and to said secondary stop plate on the other hand.

Description

TECHNICAL FIELD

[0001] The present invention relates to the field of liquefied gas storage installations comprising sealed insulated tanks with a sealing membrane. In particular, the present invention relates to the field of sealed insulated tanks for storing and / or transporting cryogenic liquefied gas, such as tanks for transporting liquefied petroleum gas (also called LPG) at a temperature for example between -50°C and 0°C or for transporting liquefied natural gas (LNG) at about -162°C at atmospheric pressure. These tanks can be installed on shore or on a floating structure. In the case of a floating structure, the tanks can be intended for transporting liquefied gas or for receiving liquefied gas used as fuel to propel the floating structure. BACKGROUND

[0002] Sealed insulated tanks integrated in a support structure of a carrier are known in the prior art, which comprise a secondary insulating barrier, a secondary sealing membrane, a primary insulating barrier and a primary sealing membrane. The tank has a plurality of tank walls assembled to each other. The sealing membranes each have a plurality of parallel panels. Each panel has a flat central portion extending in a first direction, and two raised edges protruding with respect to the central portion towards the interior of the tank on either side of the flat central portion. The panels are thus juxtaposed in a repeated pattern along a second direction and are welded together at the raised edges.

[0003] The sealing membranes are fixed to the support structure at the corners of the tank using connecting rings. Each connecting ring is fixed to the support structure on the one hand and to the sealing membrane on the other hand, to allow the transmission of stresses between the membrane and the hull of the carrier.

[0004] In particular, the connecting rings make it possible to absorb traction and compression stresses resulting from the thermal contraction of the sealing membrane, the deformation of the hull (for example in relation to the flexing of the ship's girder) and the degree of filling of the tank. In particular, such sealing membranes, often called tensioned membranes, are different from corrugated membranes, which do not have areas to absorb traction and compression stresses in the first direction.

[0005] In this type of structure, the sealing membrane must be interrupted at openings, for example to allow the passage of loading / unloading pipes.

[0006] At these interruptions, the secondary sealing membrane stops and is directly connected to the support structure.

[0007] Document KR1020180073950 describes a system for supporting a secondary sealing membrane at such an interruption, the system taking the form of a liquid dome. Therefore, the tank includes secondary fixed supports (referred to in this document as "chairs"), which are fixed to a support structure and aligned along an edge extending in a second direction of the liquid dome. Ending secondary insulating blocks are inserted between each of these chairs. A secondary stop beam extending in the second direction is then placed above the chairs and the ending secondary insulating blocks and secured to the chairs by a plurality of fasteners. These fasteners hold the secondary stop beam in both the first and second directions. The secondary sealing membrane is secured to the secondary stop beam.

[0008] However, this system is not entirely satisfactory because it is difficult to assemble, especially at the point where the secondary stop beam is fixed, and its absorption of tensile stress from the secondary sealing membrane is not optimal. Summary of the Invention

[0009] One idea that forms the basis of this invention is to simplify the stopping of the secondary sealing membrane near the opening.

[0010] Another idea that forms the basis of this invention is to improve stress absorption at the point where the secondary sealing membrane stops.

[0011] According to one embodiment, the present invention provides a liquefied gas storage facility, which includes a metal support structure and a sealed, insulated storage tank disposed in the support structure.

[0012] The storage tank includes, in the thickness direction from the outside to the inside of the tank: a secondary insulation barrier fixed to the supporting structure; a metal secondary sealing membrane disposed on the secondary insulation barrier; a primary insulation barrier disposed on the secondary sealing membrane; and a primary sealing membrane disposed on the primary insulation barrier and for contacting the liquefied gas.

[0013] The support structure includes an upper support wall.

[0014] The storage tank includes a top wall fixed to the upper support wall.

[0015] The secondary thermal insulation barrier of the top wall comprises juxtaposed secondary insulating blocks.

[0016] The secondary sealing membrane of the top wall comprises a plurality of parallel rows of plates extending along a first direction, each row of plates including a flat central portion resting on the upper surface of the secondary insulating block and two raised edges projecting toward the interior of the tank relative to the central portion. The rows of plates are juxtaposed in a repeating pattern along a second direction perpendicular to the first direction and are sealingly welded together at the raised edges. The top wall is partially interrupted to define a loading / unloading opening for a loading / unloading pipe to pass through, the loading / unloading opening interrupting at least one of the rows of plates.

[0017] The secondary insulating block includes an end secondary insulating block adjacent to the loading / unloading opening along the first direction.

[0018] The storage facility includes at least two fixed supports fixed to the upper support wall and located on either side of the end insulating block along the second direction. Each fixed support includes a secondary leg having a base length extending along the first direction and a secondary cap fixed to the secondary leg. The secondary thermal insulation barrier includes a secondary stop plate disposed on the end secondary insulating block.

[0019] The secondary stop plate and the secondary cap form a flat support surface for the secondary sealing membrane, and

[0020] The secondary sealing membrane is fixed to the secondary cap of the two fixed supports on one hand and to the secondary stop plate on the other hand.

[0021] These features make stopping the secondary membrane near the opening less complicated and allow for better absorption of stress from the secondary sealing membrane. Specifically, unlike existing technologies, the secondary sealing membrane is fixed to both the secondary stop plate and the fixed support. Furthermore, the secondary sealing membrane is supported by the secondary cap and the secondary stop plate in the same plane. Therefore, the fixed support directly absorbs some of the stress borne by the secondary sealing membrane without the mediation of the secondary stop plate, which reduces the stress transmitted to the secondary stop plate to some extent.

[0022] According to an implementation, such a storage facility may include one or more of the following features.

[0023] According to one embodiment, the secondary sealing membrane includes a metal secondary fixing plate fixed to the upper surface of the secondary stop plate.

[0024] And the end portion of the plate or each column plate interrupted by the loading / unloading opening is welded to the metal secondary fixing plate.

[0025] According to one embodiment, the secondary stop plate includes a main body, a first protrusion extending from the main body along a second direction, and a second protrusion extending from the main body along the second direction, the first protrusion and the second protrusion being located on either side of the main body, the lower surface of the main body being placed against the end secondary insulating block, the first protrusion being located below the secondary cap of one of the fixed supports, and the second protrusion being located below the secondary cap of the other of the fixed supports, the translation of the first protrusion and the second protrusion in the first direction being blocked by the fixed support, thereby transmitting the stress borne by the secondary stop plate to the fixed support along the first direction.

[0026] Therefore, the protrusion makes it possible to easily transfer the stress from the secondary sealing membrane to the fixed support along the first direction.

[0027] According to one embodiment, the first protrusion and the second protrusion are fixed to the secondary cap of the fixed support, for example, by screw engagement or welding.

[0028] According to one embodiment, the secondary leg includes a first branch and a second branch spaced apart from the first branch along the first direction, the first branch and the second branch connecting the secondary cap to the upper support wall, the first protrusion and the second protrusion being located below the secondary cap and between the first branch and the second branch of the secondary leg.

[0029] The spacing between the first branch and the second branch at the upper support wall along the first direction corresponds to the base length.

[0030] According to one embodiment, the first protruding portion and the second protruding portion are formed as a single piece with the main body.

[0031] According to one embodiment, the secondary stop plate includes two metal baffles inserted into two grooves on the upper surface of the secondary stop plate, such that a portion of one of the metal baffles forms the first protrusion and a portion of the other metal baffle forms the second protrusion, wherein the metal baffles are preferably welded to the secondary cap of the fixing support.

[0032] According to one embodiment, the body is made of plywood.

[0033] According to one embodiment, the storage facility includes a retaining rod extending along the second direction and including a first end welded to one of the two fixed supports and a second end welded to the other of the two fixed supports. The retaining rod is positioned against the sidewall of the secondary stop plate to reinforce the obstruction of translational movement of the secondary stop plate away from the loading / unloading opening along the first direction.

[0034] According to one embodiment, the storage facility includes a plurality of fixed supports juxtaposed in the second direction along one edge of the loading / unloading opening, with two adjacent fixed supports separated from each other by end secondary insulating blocks.

[0035] According to one embodiment, the secondary insulation barrier includes a plurality of secondary stop plates aligned along the second direction, each secondary stop plate being arranged between two adjacent fixed supports.

[0036] According to one embodiment, the storage facility includes a connecting bracket extending along the second direction to sealably separate the secondary insulation barrier from the loading / unloading opening. The connecting bracket includes a first wing and a second wing connected to the first wing. The first wing is welded to the metal secondary fixing plate or the secondary stop plate, and the second wing is connected to the upper support wall.

[0037] According to one embodiment, the support structure includes a rear cofferdam wall and a front cofferdam wall located on either side of the tank along the first direction, the loading / unloading opening is formed near the rear cofferdam wall, and the fixed support is arranged between the loading / unloading opening and the front cofferdam wall.

[0038] According to one embodiment, each fixed support includes a secondary support portion and a primary support portion welded to the upper support wall, the secondary support portion including the secondary cap and the secondary leg, and the primary support portion being welded to the secondary cap of the secondary support portion.

[0039] According to one embodiment, the primary sealing membrane is fixed to the primary support portion by one or more primary stop beams.

[0040] According to one embodiment, the tank includes a cover placed in a loading / unloading opening, the cover including a metal sealing wall and an insulating structure located between the sealing wall and an upper support wall, the cover being secured to the upper support wall.

[0041] According to one embodiment, the fixing support is made of steel.

[0042] The primary sealing membrane can be manufactured in a variety of ways. According to one embodiment, the primary sealing membrane of the top wall includes a plurality of parallel rows of plates extending along a first direction. Each row of plates includes a flat central portion resting against a primary insulating block of a primary insulation barrier and two raised edges protruding toward the interior of the tank relative to the central portion. The rows of plates are juxtaposed in a repeating pattern along a second direction and are sealed together at the raised edges. Anchoring wings are anchored to the primary insulating block and parallel to the first direction. The anchoring wings are arranged between the juxtaposed rows of plates to hold the primary sealing membrane on the primary insulation barrier.

[0043] According to one embodiment, the distance between two adjacent fixed supports along the second direction is an integer multiple of the dimension of the column plate along the second direction, for example, equal to the dimension of the column plate along the second direction.

[0044] According to one embodiment, the dimension of the column plate along the second direction is equal to 500 mm.

[0045] According to one embodiment, the thickness of the end portion of the plate welded to the metal secondary fixing plate is greater than the thickness of the plate at a certain distance from the loading / unloading opening.

[0046] The thickness is a dimension measured along the thickness direction, in other words, a direction perpendicular to the first and second directions.

[0047] According to one embodiment, the dimension of the end portion is greater than or equal to 1.5 mm. At a certain distance from the end, the thickness of the plate can be less than 1 mm, for example, between 0.7 mm and 1 mm.

[0048] According to one embodiment, the base length of the secondary support portion along the first direction is greater than or equal to 300 mm.

[0049] According to one embodiment, the base length of the primary support portion along the first direction is between 100 mm and 200 mm, for example, 165 mm.

[0050] Such storage facilities can be, for example, onshore storage facilities for storing LNG, or they can be coastal or deep-water floating structures (specifically liquefied gas carriers), floating storage and regasification units (FSRUs), remote floating production and storage units (FPSOs), etc. Such facilities can also be used as fuel tanks in any type of carrier.

[0051] According to one embodiment, the storage facility is manufactured in the form of a floating structure, the support structure being composed of a double-layered hull of the floating structure, and the first direction being the longitudinal direction of the floating structure.

[0052] According to one embodiment, the floating structure is a carrier for transporting cold liquid products.

[0053] According to one embodiment, the present invention also provides a system for transporting cold liquid products, the system comprising: a storage facility as described above; an insulated conduit arranged to connect a tank mounted in the hull of the carrier to an external floating or shore storage facility; and a pump for pumping a flow of cold liquid products from the external floating or shore storage facility to the tank of the carrier or from the tank of the carrier to the external floating or shore storage facility via the insulated conduit.

[0054] According to one embodiment, the present invention also provides a method for loading or unloading a storage facility as described above, wherein cold liquid products are transported from an external floating or onshore storage facility to the tank of the carrier or from the tank of the carrier to the external floating or onshore storage facility via insulated pipelines. Attached Figure Description

[0055] The invention will be better understood in the following description of several specific embodiments thereof, which are provided by way of non-limiting illustration only with reference to the accompanying drawings, and other objects, details, features and advantages of the invention will become clearer.

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Figure 1

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Figure 2

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Figure 3

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Figure 4

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Figure 5

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Figure 6

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Figure 7

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Figure 8

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Figure 9

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Figure 10

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Figure 11

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Figure 12

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Figure 13

[0069] By convention, "upper," "above," or "upper part" refers to a location closer to the interior of the tank, while "lower," "below," or "lower part" refers to a location closer to the supporting structure of the vessel, regardless of the orientation of the tank wall relative to the Earth's gravitational field. Therefore, Figures 3 to 11 The orientation shown is opposite to their actual location in the storage facility.

[0070] Figure 1 A liquefied gas carrier 70 for storing and transporting liquefied gas is shown. However, the invention is not limited to this type of carrier.

[0071] Figure 1The illustrated carrier 70 includes a storage facility 1 with four tanks 71 arranged within a support structure 2 formed by and fixed to the inner hull of the carrier 70. Each tank 71 is polyhedral in shape and has multiple tank walls assembled to each other in a manner that forms an internal space 3, specifically a top wall 4, a rear cofferdam wall 5, and a front cofferdam wall 6. The front cofferdam wall 6 and the rear cofferdam wall 5 are spaced apart along the longitudinal direction L of the carrier 70 and fixed to the top wall 4 at their tops. For loading and unloading these tanks 71, loading / unloading openings 7 are formed in the top wall 4, allowing loading / unloading pipes to pass through. The top wall 4 is fixed to an upper support wall 8 of the support structure 2. The upper support wall 8 also has holes through which loading / unloading pipes pass through the support structure 2.

[0072] Loading / unloading opening 7 serves as a penetration point for various equipment projects used for LNG processing, such as filling lines, emergency pump lines, discharge lines connected to discharge pumps, spray lines, supply lines connected to spray pumps, etc. Furthermore, the operation of this equipment is known.

[0073] Figure 2 The diagram schematically illustrates the dihedron formed by assembling the top wall 4 and the rear cofferdam wall 5. Specifically, the loading / unloading opening 7 is formed in the top wall 4, close to the rear cofferdam wall 5.

[0074] The multi-layered structure of the top wall 4 will be described in more detail below.

[0075] The multi-layered structure of the top wall 4 of the sealed and insulated tank 71 for storing liquefied gases (such as liquefied natural gas (LNG)) includes, in the thickness direction from the outside to the inside of the tank: a secondary insulation barrier 10 held on the upper support wall 8; a secondary sealing membrane 11 resting on the secondary insulation barrier 10; a primary insulation barrier 12 resting on the secondary sealing membrane 11; and a primary sealing membrane 13 resting on the primary insulation barrier 12 and intended to contact the liquefied natural gas contained in the tank 71.

[0076] The secondary insulation barrier 10 includes a plurality of secondary insulating blocks 14, which are anchored to the upper support wall 8 by means of anchoring devices (not shown). The secondary insulating blocks 14 have a generally parallelepiped shape and are arranged in parallel rows, for example, along the longitudinal direction L and the transverse direction T perpendicular to the longitudinal direction L.

[0077] The secondary sealing membrane 11 of the top wall 4 includes a continuous row of plates 15, which are metallic and have raised edges, such as... Figure 7As shown. The row plate 15 has a flat central portion resting on the secondary insulating block 14 of the secondary insulation barrier 10, and also includes two raised edges located on either side of the flat central portion in the lateral direction T and projecting toward the interior of the tank relative to the flat central portion. The row plate 15 is welded to parallel weld supports via its raised edges, the supports being fixed in grooves formed in the surface of the secondary insulating block 14 that contacts the secondary sealing membrane 11. The row plate 15 is, for example, made of... It is made of an alloy of iron and nickel, and its coefficient of thermal expansion is typically around 1.2 × 10⁻⁶. -6 With 2×10 - 6 K -1 between.

[0078] like Figure 2 As can be seen, the primary insulation barrier 12 of the top wall 4 has a plurality of primary insulating blocks 18, which are anchored to the upper support wall 8 by means of anchoring devices (not shown). The primary insulating blocks 18 have a generally parallelepiped shape. Furthermore, their dimensions may be substantially the same as or different from those of the secondary insulating blocks 14. The primary insulating blocks 18 are positioned aligned with the secondary insulating blocks 14, or offset from the secondary insulating blocks in either or both of the longitudinal direction L and the transverse direction T.

[0079] Secondary insulating block 14 and primary insulating block 18 can be made in different ways. For example, all or some of them can be made in the form of a box, which includes a bottom plate, a cover plate and a supporting shell that extends in the thickness direction between the bottom plate and the cover plate and defines a plurality of compartments filled with an insulating lining such as perlite, glass wool or rock wool.

[0080] In another embodiment, all or some of the secondary insulating block 14 and the primary insulating block 18 include a base plate, a cover plate, and one or more layers of insulating polymer foam sandwiched between the base plate and the cover plate and adhesively bonded to these plates. Specifically, the insulating polymer foam may be a polyurethane-based foam, optionally reinforced with fibers.

[0081] In another embodiment, the secondary insulation barrier 10 and / or the primary insulation barrier 12 include a secondary insulating block 14 and / or a primary insulating block 18, which have at least two different types of structures, such as the two structures described above, depending on their placement within the tank. An example of such a structure is provided in the published document WO-A-2019077253.

[0082] The primary sealing membrane 13 comprises a continuous metal plate with raised edges, the plate having, for example, the same properties as the plate 15 of the secondary sealing membrane 11. The plate of the primary sealing membrane 13 is welded to parallel welding supports via its raised edges, the supports being fixed in grooves formed in the surface of the primary insulating block 18 that contacts the primary sealing membrane 13.

[0083] The secondary sealing membrane 11 and the primary sealing membrane 13 are secured to the support structure 2 in a known manner using a connecting ring 55, specifically at the corner formed between the top wall 4 and the rear cofferdam wall 5. Thus, the connecting ring 55 is secured to the support structure 2 on one hand and to the sealing membranes 11, 13 on the other hand, to allow stress to be transferred between the sealing membranes 11, 13 and the support structure 2.

[0084] To define the loading / unloading opening 7, the top wall 4 is partially interrupted to allow the loading / unloading pipe to pass through. Therefore, the sealing membranes 11, 13 and the insulation barriers 10, 12 completely surround the interruption of the loading / unloading opening 7, as... Figure 2 As shown.

[0085] To ensure continuity of sealing and insulation, the tank 71 has a cover 19 positioned in the loading / unloading opening 7. The cover 19 includes a metal sealing wall 20 and an insulating structure 21 positioned between the metal sealing wall 20 and the upper support wall 8. The cover 19 is secured to the upper support wall 8. The metal sealing wall 20 ensures continuity of the seal with the primary sealing membrane 13 of the top wall 4, while the insulating structure 21 ensures continuity of insulation.

[0086] The insulation structure 21 may include, for example, a cover insulation block made in the form of a box, the box including a base plate, a cover plate, and a supporting shell extending in the thickness direction between the base plate and the cover plate, defining a plurality of compartments filled with an insulating liner such as rigid insulating foam. The cover insulation block has through holes (not shown) for loading / unloading conduits to pass through.

[0087] The sealing wall 20 of the cover 19 comprises, for example, a plurality of flat metal plates welded to each other. The sealing wall 20 further includes a plurality of cover openings (not shown) through which loading / unloading conduits are intended to pass. The storage facility 1 further includes a metal connecting strip 24 for sealingly connecting the sealing wall 20 of the cover and the primary sealing membrane 13 of the top wall 4, such as... Figure 2 As shown.

[0088] When the primary sealing membrane 13 is connected to the sealing wall 20 of the cover 19 at the loading / unloading opening 7, the secondary sealing membrane 11, in itself, is interrupted at the edge of the loading / unloading opening 7 and is directly and sealingly connected to the upper support wall 8 to ensure a seal between the secondary insulation barrier 10 and the cover 19. This connection is formed using a secondary connection bracket 36, which includes a first-stage wing 37 and a second-stage wing connected to the first-stage wing 37. The first-stage wing 37 is welded to the secondary sealing membrane 11, and the second-stage wing is welded to an anchor plate 69 rigidly fixed to the upper support wall 8.

[0089] At the connection with the upper support wall 8, the secondary sealing membrane 11 can transmit the compressive and traction stresses associated with its operation to the secondary connecting bracket 36. These stresses are particularly high at the forward longitudinal end edge 25 of the loading / unloading opening 7, which is the edge of the loading / unloading opening 7 located longitudinally L between the cover 19 and the forward cofferdam wall 6. Specifically, because the cover 19 is located close to the aft cofferdam wall 5, the longitudinal dimension of the secondary sealing membrane 11 between the cover 19 and the forward cofferdam wall 6 is much larger than that between the cover 19 and the aft cofferdam wall 5, which creates much higher stresses at the forward longitudinal end edge 25 when the hull undergoes thermal deformation or contraction. Furthermore, these stresses are particularly high at the forward longitudinal end edge 25 due to the orientation of the secondary sealing membrane 11. Specifically, the secondary sealing membrane 11 is oriented such that the flat central portion of the row plate 15 extends in the longitudinal direction L of the carrier 70. Therefore, there is no area for absorbing traction and compressive stresses in this direction.

[0090] In order to disconnect the secondary connecting bracket 36 and the welding to the secondary sealing membrane 11, a specific support structure is provided along the front longitudinal end edge 25 extending in the transverse direction T, which will be described in detail below.

[0091] Figure 3 Specifically, the arrangement of the support structure at the front longitudinal end edge 25 of the loading / unloading opening 7 according to the first embodiment is shown.

[0092] like Figure 3 As shown, the storage facility 1 includes a plurality of metal fixed supports 26 arranged side by side in the transverse direction T, which are spaced apart from each other at regular intervals along the front longitudinal end edge 25 of the loading / unloading opening 7.

[0093] Each fixed support 26 includes a secondary support portion 27 and a primary support portion 28 welded to the secondary support portion 27. The secondary support portion 27 has a secondary cap 29 extending in the longitudinal direction to which the primary support portion 28 is welded. The secondary cap 29 is welded to a secondary leg 30, which is anchored to the upper support wall 8, for example, by welding or screwing. Thus, the secondary support portion 27 has a base length extending in the longitudinal direction L (measured at the point where the secondary leg 30 is fixed to the support structure), thereby making it possible to counteract swaying and deflection in that direction. The primary support portion 28 also has a primary cap 31 (not shown in the first embodiment). The primary cap 31 is welded to a primary leg 32, which is welded to the secondary cap 29. The primary support portion 28 also has a base length extending in the longitudinal direction L (measured at the point where the primary leg 32 is fixed to the secondary leg 30), thereby making it possible to counteract swaying and deflection in that direction.

[0094] exist Figure 8 The second embodiment shown and Figure 10 In the third embodiment shown, the secondary leg 30 and the primary leg 32 are manufactured as beams having an H-shaped cross-section (a cross-sectional shape in a plane perpendicular to the thickness direction). Figure 3 In the first embodiment specifically shown, the primary support leg 32 is made in the form of a beam with a circular cross-section (the cross-sectional shape in a plane perpendicular to the thickness direction), and the secondary support leg 30 is made in the form of an H-shaped beam. The secondary support leg 30 includes a first branch 67 formed by a plate and a second branch 68 formed by a plate spaced apart from the first branch 67 along the longitudinal direction L by a connecting plate 99. The distance along the longitudinal direction L between the first branch 67 and the second branch 68 on the upper support wall 8 corresponds to the base length. The reinforcing portion 82 is welded to the upper support wall 8 and extends along the longitudinal direction L, so as to be welded to the edge of the first branch 67 at the first end and to the edge of the second branch 68 at the second end. In this case, the secondary support portion 27 is preferably provided with two reinforcing portions 82 located on either side of the connecting plate 99, such as Figure 3 As shown.

[0095] Other cross-sectional shapes of the primary outrigger 32 and secondary outrigger 30 may also be used, as long as they provide sufficient moment of inertia in the longitudinal direction L.

[0096] The secondary insulation barrier 10 includes terminal secondary insulation blocks 34. Each terminal secondary insulation block 34 is inserted between the secondary support portions 27 of two adjacent fixed supports 26 in the lateral direction T. A secondary stop plate 83 is fixed to the upper surface of each terminal secondary insulation block 34, for example, using putty (not shown).

[0097] Figure 4This assembly state in the first embodiment is specifically shown, in which the secondary stop plate 83 and the end secondary insulating block 34 are placed in the appropriate position. Figure 8 This assembly state is also shown in the second embodiment, while Figure 10 This assembly state is also shown in the third embodiment.

[0098] The differences between the various implementations lie particularly in the design of the fixed support 26, and also in the design of the secondary stop plate 83.

[0099] In each embodiment, the secondary stop plate 83 includes a body 84, a first protrusion 85 projecting from the body 84 in a transverse direction T, and a second protrusion 86 also projecting from the body 84 in a transverse direction T. The first protrusion 85 and the second protrusion 86 are located on either side of the body 84. The body 84 is made of plywood.

[0100] like Figure 4 , Figure 8 and Figure 10 As can be seen, the first protrusion 85 is located below the secondary cap 29 of one of the fixed supports 26 adjacent to the secondary stop plate 83, while the second protrusion 86 is located below the secondary cap 29 of the other of the adjacent fixed supports 26. The translation of the first protrusion 85 and the second protrusion 86 in the longitudinal direction L is blocked by the fixed support 26 in various ways (depending on the embodiment), thereby transmitting the stress borne by the secondary stop plate 83 to the fixed support 26 in the longitudinal direction L.

[0101] Regarding the first implementation method Figure 5 and Figure 6 Two design variations of the secondary stop plate 83 of this embodiment are shown. In both variations, the secondary stop plate 83 includes two metal stop plates 87. The stop plates 87 are inserted into two recesses 88 located on the upper surface of the secondary stop plate 83 and are advantageously held in place in the recesses 88 by fastening members such as screws (not shown), each screw passing through a hole in one of the stop plates and received in a threaded hole formed in the body of the secondary stop plate 83. The stop plates 87 are positioned such that a portion of one of the stop plates 87 forms a first protrusion 85, and a portion of the other stop plate 87 forms a second protrusion 86. A wedge 89 may be positioned at the rear of the recesses 88 to fill the remaining space left in the recesses 88 for inserting and positioning the stop plates 87. In this first embodiment, the stop plates 87 are thus welded to one of the secondary caps 29 of the adjacent fixing support 26. The secondary stop plate 83 also has a metal fixing bracket 90 screwed to the upper surface on the near upper edge of its loading / unloading opening 7.

[0102] exist Figure 4 and Figure 5 In the first variant shown, a retaining rod 91 extending laterally in the plane of the secondary stop plate 83 is welded at its first end to one of the secondary legs 30 of the two adjacent fixed supports 26, and at its second end to the other of the two adjacent fixed supports 26. The retaining rod 91 is positioned against the sidewall of the secondary stop plate 83, thereby stiffening the secondary stop plate 83 and reinforcing the resistance to longitudinal translation of the secondary stop plate 83 in the direction from the loading / unloading opening 7 toward the front cofferdam wall 6. The sidewall of the secondary stop plate 83 is the sidewall furthest from the loading / unloading opening 7.

[0103] Furthermore, advantageously, the baffle plate 87 contacts only one sidewall of the groove 88, which is furthest from the loading / unloading opening 7. Therefore, the baffle plate 87 makes it possible to stiffen the secondary stop plate 83 and reinforce the obstruction of longitudinal translation of the secondary stop plate 83 in the direction from the front cofferdam wall 6 toward the loading / unloading opening 7. Thus, the secondary stop plate 83 is held between the baffle plate 87 and the retaining rod 91.

[0104] The sidewall of the secondary stop plate 83 may advantageously include a reinforcement 92, such as Figure 5 As shown, this is to accommodate the retaining rod 91. Therefore, the reinforcing member 92 extends laterally parallel to and at a distance from the sidewall of the secondary stop plate 83. The reinforcing member 92 has a metal plate on which the retaining rod 91 is pressed. The retaining rod 91 advantageously has a U-shaped cross-section (observed in a plane perpendicular to the lateral direction), the base of which is pressed against the metal plate of the reinforcing member 92.

[0105] exist Figure 6 In the second variant shown, the retaining rod 91 is replaced by a reinforcing rod 93. The reinforcing rod 93 is positioned in a recessed extension 94, which is formed in the upper surface of the secondary stop plate 83 and connects the two recesses 88. The reinforcing rod 93 is welded at a first end to one of the stop plates 87 and at a second end to the other of the stop plates 87, thereby stiffening the secondary stop plate 83 and strengthening its resistance to translation.

[0106] Figure 7 The assembly state is shown, where... Figure 4 In contrast, a secondary sealing membrane 11 is shown.

[0107] The secondary sealing membrane 11 includes a metal secondary fixing plate 35. Figure 7 In the first embodiment shown, with Figure 8 The second implementation is the same (although this is in) Figure 8(Not shown in the image), a metal secondary fixing plate 35 extends over both the upper surface of the secondary stop plate 83 and the secondary cap 29. For this purpose, the metal secondary fixing plate 35 has a through hole 95 at each secondary cap 29, allowing the primary support portion 28 to pass through. The metal secondary fixing plate 35 is welded to the fixing bracket 90 of the secondary stop plate 83, completely surrounding the secondary cap 29 and the through hole 95 on the proximal edge 96. The distal edge 97 of the metal secondary fixing plate 35 is also screwed to the upper surface of the secondary stop plate 83. The primary stage wing 37 of the secondary connecting bracket 36 is also welded to the proximal edge 96, while the end portion of the column plate 15, interrupted by the loading / unloading opening 7, is welded to the distal edge 97 of the metal secondary fixing plate 35, as shown. Figure 7 As shown.

[0108] exist Figure 10 In the third embodiment shown, metal secondary fixing plates 35 are screwed to each secondary stop plate 83 on the proximal edge 96 and the distal edge 97, such that each metal secondary fixing plate 35 extends only over the secondary stop plate 83 in this case. Therefore, the primary wing 37 of the secondary connecting bracket 36 is welded to the proximal edge 96 and the secondary cap 29, while the end portion of the column plate 15 interrupted by the loading / unloading opening 7 is welded to the distal edge 97 and the secondary cap 29 of the metal secondary fixing plate 35.

[0109] Figure 8 and Figure 9 A second embodiment is shown, specifically for the fixed support 26 as described above and for the secondary stop plate 83. In this embodiment, the main body 84 and the protrusions 85, 86 are made of plywood as a single piece. However, the protrusions 85, 86 are reinforced by pre-drilled metal plates 98. Thus, the protrusions 85, 86 are positioned below the secondary cap 29 of one of the secondary support portions 27 and between the branches 67, 68 of the secondary support leg 30, and are secured to the secondary cap 29 using screw-connected fixing members, and also secured to the secondary support leg 30 using the pre-drilled metal plates 98.

[0110] Figure 10 and Figure 11 A third embodiment is shown, specifically for the fixed support 26 as described above and for the secondary stop plate 83. In this embodiment, the main body 84 and the protrusions 85 and 86 are also made of plywood as a single piece. This time, the protrusions 85 and 86 are not fixed to the secondary legs at the secondary caps 29 and 30 using screw-jointed fixing members, but are simply located adjacent to the two branches 67 and 68 of the secondary leg 30 and abut against the secondary cap 29. Furthermore, as in the first embodiment, the retaining rod 91 is arranged in the reinforcement 92 abutting against the side wall of the secondary stop plate 83 and is welded to the secondary leg 30 at its end.

[0111] The connection between the primary sealing membrane 13 and the primary support portion 28 is only here Figure 2 The connection is schematically shown in the diagram. This connection can be formed similarly to the secondary sealing membrane 11. Specifically, the end primary insulating blocks are arranged between the primary support portions 28, and then a primary stop beam extending in the lateral direction T is placed on the upper surface of the primary cap 31 and the end primary insulating blocks. Then, if the primary stop beam is made of plywood, it is secured to the primary cap 31 using supports and fixing devices; or if the primary stop beam is made of metal, it is secured to the primary cap 31 by welding. Then, the primary connecting bracket is secured to the primary stop beam on one side and to the secondary connecting bracket 36 on the other. The end portion of the column plate 15 of the primary sealing membrane 13, interrupted by the loading / unloading opening 7, is secured to the primary stop beam. Finally, a metal connecting strip 24 connects the primary sealing membrane 13 to the sealing wall 20 of the cover 19, as shown in the diagram. Figure 2 This can be seen from the text.

[0112] Figure 12 Another variant implementation of the fixing device is shown. Specifically, in this variant, the fixing support 26 includes cap reinforcement 102, in which two cap reinforcements are present, welded below the secondary cap 29 and extending in a plane perpendicular to the longitudinal direction L. In the example shown, the cap reinforcement 102 is positioned in a straight line with the two diameter-opposite portions of the primary support leg 32.

[0113] The reinforcing portion 103 is welded to the upper support wall 8 and extends in the longitudinal direction L, in such a way that it is welded to the edge of the first branch 67 at the first end and to the edge of the second branch 68 at the second end. In this case, the secondary support leg 30 preferably has two reinforcing portions 103 located on either side of the link plate 99, which is advantageously fixed to these branches in the transverse direction T between the first branch 67 and the second branch 68, as... Figure 12 Specifically shown.

[0114] In other embodiments not shown, to advantageously facilitate welding operations, the reinforcing portion 103 or the connecting plate 99 may not be welded to the upper support wall 8. In this case, the component not fixed to the upper support wall 8, whether it is the reinforcing portion 103 or the connecting plate 99, can be positioned at a distance from the upper support wall 8.

[0115] exist Figure 12 The variant shown is different from the one shown. Figure 3 In a variant, the link plate 99 has a center hole 100, which is preferably elliptical and extends in the longitudinal direction L to increase the flexibility of the fixing support 26.

[0116] The connecting plate 99 may have a rounded corner 101 formed at the corner of the connecting plate 99 to limit stress concentration. Similarly, the reinforcing portion 103 may also have a rounded corner 101 formed at the corner of the reinforcing portion 103 located at the joint between one of the branches 67, 68 and the upper support wall 8.

[0117] refer to Figure 13 The view of the liquefied gas carrier 70 (partially cut off) shows a generally prismatic, sealed, and insulated storage tank 71 installed within the double-hulled structure 72 of the carrier. The walls of the storage tank 71 include a primary sealing barrier intended to contact the LNG contained within the tank, a secondary sealing barrier disposed between the primary sealing barrier and the double-hulled structure 72 of the carrier, and two insulating barriers disposed between the primary and secondary sealing barriers and between the secondary sealing barrier and the double-hulled structure 72, respectively.

[0118] In a manner known per se, the loading / unloading pipeline 73, arranged on the upper deck of the vessel, can be connected to a marine or port terminal by means of appropriate connectors to transport cargo LNG to and from the storage tank 71.

[0119] Figure 13 An example of a marine terminal is shown, comprising a loading and unloading station 75, underwater pipelines 76, and onshore facilities 77. The loading and unloading station 75 is a fixed offshore facility including a movable boom 74 and a tower 78 supporting the movable boom 74. The movable boom 74 carries a bundle of insulated flexible tubing 79 that can be connected to a loading / unloading pipeline 73. The directional movable boom 74 is adjustable to accommodate liquefied gas carriers of all sizes. Connecting pipes (not shown) extend inside the tower 78. The loading and unloading station 75 allows the loading of liquefied gas carriers 70 from or the unloading of said liquefied gas carriers to the onshore facility 77. The facility includes storage tanks 80 for storing liquefied gas and connecting pipes 81 that connect to the loading and unloading station 75 via the underwater pipeline 76. The underwater pipeline 76 allows for the transport of liquefied gas over a longer distance (e.g., 5 km) between the loading or unloading station 75 and the onshore facility 77, which makes it possible to keep the liquefied gas carrier 70 at a greater distance from the shore during loading and unloading operations.

[0120] In order to generate the pressure necessary for transporting liquefied gas, pumps on carrier 70 and / or pumps connected to shore facility 77 and / or pumps connected to loading and unloading station 75 are used.

[0121] Although the invention has been described in conjunction with several specific embodiments, it is apparent that the invention is by no means limited thereto, and that if the described apparatus falls within the scope of the invention, the invention includes all technical equivalents of the described apparatus and combinations thereof.

[0122] The use of the verbs “comprising” or “including” and their variant forms does not preclude the presence of other elements or steps besides those stated in the claims.

[0123] Any reference numerals in parentheses in the claims should not be construed as limiting the claims.

Claims

1. A liquefied gas storage installation (1) comprising a metal support structure (2) and a sealed thermally insulated tank (71) arranged in said support structure, The tank includes, in a thickness direction from the outside to the inside of the tank: - a secondary thermal barrier (10) fixed to said support structure (2), a metal secondary sealing membrane (11) arranged on said secondary thermal barrier (10), a primary thermal barrier (12) arranged on said secondary sealing membrane (11), and a primary sealing membrane (13) arranged on said primary thermal barrier (12) and intended to be in contact with said liquefied gas, - said support structure comprising an upper support wall (8), - said tank (71) comprising a top wall (4) fixed to said upper support wall (8), - wherein said secondary thermal barrier (10) of said top wall comprises juxtaposed secondary insulating blocks (14), - wherein said secondary sealing membrane (11) of said top wall (4) comprises a plurality of parallel rows of plates (15) extending along a first direction (L), each row of plates (15) comprising a flat central portion resting on an upper surface of said secondary insulating blocks (14) and two raised edges projecting with respect to said central portion towards the inside of said tank, said rows of plates (15) being juxtaposed in a repetitive pattern along a second direction (T) perpendicular to said first direction (L) and being sealingly welded together at said raised edges, said top wall (4) being locally interrupted to delimit a loading / unloading opening (7) for the passage of a loading / unloading pipe, at least one of said rows of plates (15) being interrupted in said loading / unloading opening (7), - wherein said secondary insulating blocks (14) comprise end secondary insulating blocks (34) adjacent to said loading / unloading opening (7) along said first direction, - wherein said storage installation comprises at least two fixed supports (26) fixed to said upper support wall (8) and located on either side of an end secondary insulating block (34) along said second direction, each fixed support (26) comprising a secondary leg (30) having a base length extending along said first direction and comprising a secondary cap (29) fixed to said secondary leg (30), said secondary thermal barrier comprising a secondary stop plate (83) arranged on said end secondary insulating block (34), - wherein said secondary stop plate (83) and said secondary cap (29) form a flat support surface for said secondary sealing membrane (11), and - wherein said secondary sealing membrane (11) is fixed to said secondary cap (29) of said two fixed supports (26) on one hand and to said secondary stop plate (83) on the other hand.

2. The storage installation of claim 1, wherein said secondary sealing membrane (11) comprises a metal secondary fixed plate (35) fixed to an upper surface of said secondary stop plate (83), and - wherein end portions of said rows of plates (15) interrupted by said loading / unloading opening (7) are welded to said metal secondary fixed plate (35).

3. The storage facility of claim 2, wherein the secondary stop plate (83) comprises a main body (84), a first protruding portion (85) protruding from the main body (84) in the second direction (T) and a second protruding portion (86) protruding from the main body (84) in the second direction (T), the first and second protruding portions (85, 86) being located on either side of the main body (84), a lower surface of the main body (84) resting against the terminal secondary insulating block (34), the first protruding portion (85) being located under a secondary cap (29) of one of the fixed supports (26), the second protruding portion (86) being located under the secondary cap (29) of the other of the fixed supports (26), the first and second protruding portions (85, 86) being blocked in translation in the first direction (L) by the fixed supports (26), in such a way as to transmit the stresses undergone by the secondary stop plate (83) to the fixed supports (26) in the first direction (L).

4. The storage facility (1) of claim 3, wherein the first and second protruding portions (85, 86) are fixed to the secondary caps (29) of the fixed supports (26).

5. The storage facility (1) of claim 3, wherein the secondary leg (30) comprises a first branch (67) and a second branch (68) spaced apart from the first branch (67) in the first direction (L), the first and second branches connecting the secondary cap (29) to the upper support wall (8), the first and second protruding portions (85, 86) being located under the secondary cap (29) and between the first and second branches (67, 68) of the secondary leg (30).

6. The storage facility (1) of claim 3, wherein the first and second protruding portions (85, 86) are formed in one piece with the main body (84).

7. The storage facility (1) of claim 3, wherein the secondary stop plate (83) comprises two metal blocking plates (87) inserted in two grooves (88) located on an upper surface of the secondary stop plate (83), in such a way that a portion of one of the metal blocking plates (87) forms the first protruding portion (85) and a portion of the other of the metal blocking plates (87) forms the second protruding portion (86).

8. The storage facility (1) of claim 3, wherein the main body (84) is made of plywood.

9. The storage facility (1) of any one of claims 1 to 4, wherein the storage facility (1) comprises a retaining bar (91) extending along the second direction (T) and comprising a first end welded to one of the two fixed supports (26) and a second end welded to the other of the two fixed supports (26), the retaining bar (91) resting against a lateral wall of the secondary stop plate (83) in such a way to reinforce the blocking of the translation of the secondary stop plate (83) along the first direction (L) away from the loading / unloading opening (7).

10. The storage facility (1) of one of claims 1 to 4, wherein the storage facility (1) comprises a plurality of fixed supports (26) juxtaposed in the second direction along one edge of the loading / unloading opening (7), two adjacent fixed supports (26) being separated from each other by a terminal secondary insulating block (34).

11. The storage facility (1) of claim 10, wherein the secondary thermal insulation barrier (10) comprises a plurality of secondary stop plates (83) aligned along the second direction, each secondary stop plate (83) being arranged between two adjacent fixed supports (26).

12. The storage facility (1) of claim 2, wherein the storage facility (1) comprises a connecting bracket (36) extending along the second direction to seal the secondary thermal insulation barrier (10) from the loading / unloading opening (7), the connecting bracket (36) comprising a first wing (37) and a second wing connected to the first wing, the first wing (37) being welded to the metal secondary fixed plate (35) or to the secondary stop plate (83) and the second wing being connected to the upper support wall (8).

13. The storage facility (1) of one of claims 1 to 4, wherein the support structure comprises a rear cofferdam wall (5) and a front cofferdam wall (6) located on either side of the tank along the first direction, the loading / unloading opening (7) being formed close to the rear cofferdam wall (5), the fixed supports (26) being arranged between the loading / unloading opening (7) and the front cofferdam wall (6).

14. The storage facility (1) of one of claims 1 to 4, wherein each fixed support (26) comprises a secondary support portion (27) and a primary support portion (28) welded to the upper support wall (8), the secondary support portion (27) comprising the secondary cap (29) and the secondary leg (30), the primary support portion (28) being welded to the secondary cap (29) of the secondary support portion (27).

15. The storage facility (1) of one of claims 1 to 4, produced in the form of a floating structure, wherein the support structure consists of a double hull (72) of the floating structure, and wherein the first direction is a longitudinal direction (L) of the floating structure.

16. A system for transporting a cold liquid product, the system comprising: The storage facility of claim 15; insulated pipelines (73, 79, 76, 81) arranged to connect a tank (71) installed in the hull of the floating structure to an external floating or onshore storage facility (77); and a pump for pumping a flow of cold liquid product through the insulated pipelines from or to the external floating or onshore storage facility to or from the tank of the floating structure.

17. A method for loading or unloading a storage facility according to claim 15, wherein a cold liquid product is transported from or to the tank (71) of the floating structure to or from an external floating or onshore storage facility (77) through insulated pipelines (73, 79, 76, 81).

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