Heat-insulated box for a sealed and thermally insulating tank

Abstract

The invention relates to a heat-insulating box (1) comprising: a cover panel (3) and a bottom panel (2) spaced apart along a thickness direction (E) of the cover panel; side panels connecting the bottom panels and the cover panels along edges of the bottom panel and the cover panel to form an interior space; a plurality of internal partitions dividing said interior space into a plurality of compartments (6), a first compartment of the plurality of compartments comprising an insulating lining filling said first compartment, the insulating lining comprising a block of fiber-reinforced polyurethane foam (13) extending from the bottom panel to the cover panel and a first strip of compressible insulating material (20) in the compressed state and covering a lateral surface of the insulating block and capable of expanding in order to compensate for the contraction of the foam block. Figure for abstract: 2

Description

Title of the invention: Heat-insulating box for a sealed and thermally insulating tank Technical field

[0001] The invention relates to the field of sealed and thermally insulating tanks with membranes for the storage and / or transport of fluid, such as a cryogenic fluid.

[0002] Leak-proof and thermally insulating membrane tanks are used in particular for the storage of liquefied natural gas (LNG), which is stored, at atmospheric pressure, at approximately -162°C. These tanks can be installed on land or on a floating structure. In the case of a floating structure, the tank can be intended for the transport of liquefied natural gas or for receiving liquefied natural gas used as fuel for the propulsion of the floating structure.

[0003] The invention relates in particular to a heat-insulating box which is intended for the formation of a thermally insulating barrier for such a tank. Technological background

[0004] In the state of the art, sealed and thermally insulating tanks for storing liquefied natural gas are known, integrated into a supporting structure, such as the double hull of a ship intended for the transport of liquefied natural gas. Generally, such tanks comprise a multi-layer structure successively having, in the direction of the thickness, from the outside to the inside of the tank, a secondary thermal insulation barrier retained on the supporting structure, a secondary sealed membrane resting against the secondary thermal insulation barrier, a primary thermal insulation barrier resting against the secondary sealed membrane and a primary sealed membrane resting against the primary thermal insulation barrier and intended to be in contact with the liquefied natural gas contained in the tank.

[0005] It is known that such tanks can comprise heat-insulated boxes comprising a bottom panel, a cover panel, side panels and internal sails which delimit spaces in which perlite is placed.

[0006] In service, the walls of the tank are subjected to numerous stresses. In particular, the walls are subjected to compressive forces due to the loading of the tank, to thermal stresses during cooling and to forces due to the dynamic shocks of the fluid contained in the tank. Summary of the invention

[0007] The inventors have found that, when the dimensions of the tank are increased, the forces due to the dynamic shocks of the fluid contained in the tank increase accordingly and that, in such circumstances, the state-of-the-art heat-insulating boxes were likely to present insufficient resistance.

[0008] The inventors have developed a new type of heat-insulating box having greater mechanical resistance compared to currently known boxes, and this without significantly degrading the thermal insulation performance.

[0009] Another idea underlying the invention is to provide a heat-insulating box comprising an insulating lining capable of compensating for thermal contraction in order to reduce thermal bridges.

[0010] According to one embodiment, the invention provides a heat-insulated box for a sealed and thermally insulating tank intended to contain a liquefied gas, the heat-insulated box comprising: a cover panel and a bottom panel spaced apart along a thickness direction of the cover panel; side panels connecting the bottom panels and the cover panels along edges of the bottom panel and the cover panel to form an interior space;a plurality of internal partitions dividing said interior space into a plurality of compartments, a first compartment of the plurality of compartments comprising an insulating lining filling said first compartment, the insulating lining comprising a foam block which is made of fiber-reinforced polyurethane foam and which extends from the bottom panel to the cover panel so as to take up the compressive forces exerted on the cover panel in the thickness direction and a first strip of compressible insulating material which covers a lateral surface of the foam block, is arranged in a compressed state and is capable of relaxing in order to compensate for the contraction of the foam block. ;

[0011] Thanks to these characteristics, the polyurethane foam block has a structural function of absorbing compression forces, which makes it possible to give the heat-insulating box particularly advantageous characteristics of resistance to compression exerted on the heat-insulating box, in the thickness direction of said box. In addition, the heat-insulating box has excellent thermal insulation properties, in particular in the presence of thermal expansion and contraction phenomena which are present, for example, when such a heat-insulating box is integrated into a tank containing liquefied gas at very low temperatures, which can reach -162°C.In fact, when the block of fiber-reinforced polyurethane foam shrinks due to the phenomenon of thermal contraction, the compressible insulating material initially in a compressed state relaxes, which prevents the creation of gaps that promote thermal transfer.

[0012] According to embodiments, such a heat-insulating box may comprise one or several of the following characteristics.

[0013] According to one embodiment, the insulating lining fills the first compartment and comprises one or more polyurethane foam insulating blocks and one or more strips of compressible insulating material which are each compressed between said one or more insulating blocks and an internal partition, a side panel or another of the polyurethane foam insulating blocks.

[0014] According to one embodiment, the plurality of internal partitions are in contact against the bottom panel and the cover panel.

[0015] Thus, the resistance to compression exerted on the heat-insulating box is increased.

[0016] According to one embodiment, a portion of the internal partitions is oriented according to a first direction parallel to the thickness direction and another part of the internal partitions is oriented in a second direction parallel to the thickness direction, the first and second directions being orthogonal to each other.

[0017] According to one embodiment, the plurality of internal partitions comprises a first row of internal partitions extending in a first direction and a second row of internal partitions extending in a second direction which is perpendicular to the first direction.

[0018] According to one embodiment, the first row of internal partitions is in contact with a first side panel and with a second side panel which is located opposite the first side panel. According to one embodiment, the second row of internal partitions is in contact with a third side panel and with a fourth side panel which is located opposite the third side panel.

[0019] According to one embodiment, the internal partitions of the first row of internal partitions comprise a plurality of grooves extending in the direction of thickness of the heat-insulating box, and the internal partitions of the second row of internal partitions comprise a plurality of grooves extending along the thickness direction of the heat-insulating box in a manner complementary to the plurality of grooves of the first row, the internal partitions of the second row are inserted into the plurality of grooves in order to hold the first and second rows of internal partitions in place.

[0020] According to one embodiment, the internal partitions extend from the bottom panel to the cover panel so as to absorb the compression forces exerted on the cover panel in the thickness direction.

[0021] According to one embodiment, the plurality of internal partitions is made of plywood or composite material.

[0022] According to one embodiment, each internal partition of the plurality of internal partitions has a thickness of between 9 and 15 mm.

[0023] According to one embodiment, each compartment of the plurality of compartments has a general parallelepiped shape and preferably a general rectangular or square parallelepiped shape.

[0024] According to one embodiment, the fibers of the foam block are in the form of a plurality of fiber mats, each of the fiber mats extending along a plane forming an angle with the bottom panel of between 80° and 100°.

[0025] Thanks to these characteristics, the heat-insulating box has an increased compressive strength capacity in the direction of the thickness of the box, which allows better absorption of the compressive forces exerted on the cover panel in the direction of thickness. More precisely, this position of the fiber mats results in particular in a gain in compressive strength of the heat-insulating box of approximately 15% when cold, that is to say when the box is present in a tank containing liquefied gas, in comparison with foam blocks comprising fiber mats extending along a plane forming a right angle with a side panel of the box.

[0026] According to one embodiment, the fiber mats are positioned perpendicular to the bottom panel and the cover panel.

[0027] According to one embodiment, the fibers are glass fibers.

[0028] The fiber mat is a fibrous composite material comprising non-woven fibers, arranged discontinuously, having a general shape of a sheet or a strip. For example, a glass mat is made of non-woven glass fibers, arranged discontinuously.

[0029] According to one embodiment, the block of fiber-reinforced polyurethane foam comprises between 5% and 20% of fibers, preferably between 7% and 13% by mass of the foam block.

[0030] According to one embodiment, the bottom panel, the cover panel and the side panels are made of plywood.

[0031] According to one embodiment, the compressible insulating material is manufactured from a material chosen from: glass wool, rock wool and polyester wadding, the preferred material being glass wool.

[0032] According to one embodiment, the strip of insulating material has a thickness of between 5 mm and 20 mm after compression during its installation, i.e. at room temperature, and preferably between 5 mm and 10 mm.

[0033] The ambient temperature is generally between 10 and 40 degrees Celsius.

[0034] According to one embodiment, the strip of insulating material has a compression rate depending on its thickness of 5% to 30%. Thanks to this specific range, good insulation without convection phenomena is ensured and the buckling phenomenon of the heat-insulating box is greatly reduced compared to a compression rate higher than this range. Indeed, the more the compression rate increases, the more the forces exerted against the walls increase, which can lead to buckling of the walls of the heat-insulating box.

[0035] According to one embodiment, the insulating lining comprises a second strip of compressible insulating material in the compressed state covering a second lateral face of the foam block.

[0036] According to one embodiment, the second lateral face of the foam block is adjacent and perpendicular to the first lateral face.

[0037] According to one embodiment, the insulating lining comprises a third strip of compressible insulating material in the compressed state covering a third lateral face of the foam block.

[0038] According to one embodiment, the insulating lining comprises a fourth strip of compressible insulating material in the compressed state covering a fourth lateral face of the foam block, the first, second, third and fourth strips forming a lateral envelope laterally surrounding the foam block. Thus, the foam block is centered in the compartment.

[0039] According to an advantageous embodiment, all the compartments of the heat-insulating box are filled with a heat-insulating lining having a first, a second, a third and a fourth strip of compressible insulating material according to the above arrangement. Thanks to these characteristics, the mechanical behavior of the heat-insulating box having this heat-insulating lining is homogeneous. In other words, the heat-insulating box resists compression in the direction of the thickness of the heat-insulating box regardless of the distribution and location of the compression force that is exerted on the cover panel.

[0040] According to an embodiment, the first, the second, the third or the fourth strip is compressed between a surface of the foam block and a side panel.

[0041] According to one embodiment, the first, second, third or fourth strip is compressed between a surface of the foam block and an internal partition.

[0042] According to one embodiment, the first, second, third or fourth strip is compressed between a surface of the first foam block and a surface of a second foam block made of fiber-reinforced polyurethane foam.

[0043] According to one embodiment, the insulating lining comprises four foam blocks made of fiber-reinforced polyurethane foam which are each arranged in a respective corner of the compartment, the four foam blocks being respectively spaced from each other via a plurality of strips of compressible insulating material in the compressed state, the plurality of strips comprising the first strip.

[0044] According to one embodiment, all the compartments of the heat-insulating box are filled with four foam blocks and a plurality of strips of compression insulating material according to the aforementioned arrangement. Thanks to these characteristics, the behavior The mechanical properties of the heat-insulating box are homogeneous, i.e. the heat-insulating box resists compression in the thickness direction of the heat-insulating box regardless of the distribution and location of the compressive force on the cover panel. Thus, the heat-insulating box has excellent compressive strength properties in the thickness direction of the heat-insulating box. In addition, when the foam blocks are positioned against the internal partitions, the buckling phenomenon of the internal partitions is greatly reduced.

[0045] According to one embodiment, the compartments of the plurality of compartments independently comprise one or more of the characteristics indicated for the first compartment.

[0046] According to one embodiment, the plurality of compartments comprises: - peripheral compartments adjacent to at least one of the side panels; - central compartments delimited by internal partitions of the plurality of internal partitions, the first compartment being one of the central compartments, the peripheral compartments and the central compartments each comprising an insulating lining filling said peripheral compartments and said central compartments, each insulating lining comprising a foam block made of fiber-reinforced polyurethane foam extending from the bottom panel to the cover panel so as to absorb the compressive forces exerted on the cover panel in the thickness direction and a first strip of an insulating material compressible in the compressed state and covering a lateral surface of the foam block and capable of relaxing in order to compensate for the contraction of the foam block.

[0047] According to one embodiment, each side panel of the peripheral compartments is in direct contact with the foam block. In other words, the insulating lining does not comprise a strip of compressible insulating material between the fiber-reinforced polyurethane foam block and the corresponding side panel.

[0048] Thanks to these characteristics, the phenomenon of buckling of the side panels which are in direct contact with the block of fiber-reinforced polyurethane foam is greatly reduced when a compressive force is exerted on the cover panel.

[0049] According to one embodiment, the direct contact of the peripheral compartments with the foam block is carried out by gluing.

[0050] According to one embodiment, the insulating lining of each central compartment comprises four strips of compressible insulating material in the compressed state interposed respectively between the internal partitions and the foam block. In other words, the four strips laterally envelop the foam block.

[0051] According to one embodiment, the plurality of compartments comprises a set of compartments formed by the first compartment which is adjacent to a second compartment and a third compartment, as well as a fourth compartment which is adjacent to the second compartment and the third compartment, the first compartment comprising: the first compressed strip between the first lateral face of the foam block and a first internal partition which separates the first compartment and the second compartment, a second strip of compressible insulating material in the compressed state between a second lateral face of the foam block adjacent to the first lateral face and a second internal partition which separates the first compartment and the third compartment, the second compartment comprising: a first strip of compressible insulating material in the compressed state between a first lateral face of a second block of fiber-reinforced polyurethane foam and a third internal partition, a fourth strip of compressible insulating material in the compressed state between a fourth lateral face of the second block of foam and a first side panel, the third compartment comprising: a second strip of compressible insulating material in the compressed state between a second lateral face of a third block of fiber-reinforced polyurethane foam and a fourth internal partition, a third strip of compressible insulating material in the compressed state between a third lateral face of the third block of foam and a second side panel, the fourth compartment comprising: a fourth strip of compressible insulating material in the compressed state between a fourth lateral face of the fourth block of fiber-reinforced polyurethane foam and an internal partition which separates the fourth compartment and the third compartment, a third strip of compressed glass wool between a third lateral face of the fourth block of fiber-reinforced polyurethane foam and an internal partition which separates the fourth compartment and the second compartment.

[0052] Thanks to these characteristics, the heat-insulating box has excellent compressive strength properties in the thickness direction of the heat-insulating box.

[0053] According to one embodiment, the plurality of compartments comprises between two and ten sets of compartments juxtaposed to each other, preferably between four and eight sets of compartments, for example six sets of compartments.

[0054] According to one embodiment, the plurality of compartments further comprises one or more compartments of the set of compartments chosen from the first compartment, the second compartment, the third compartment or the fourth compartment.

[0055] According to one embodiment, the heat-insulating box has between 9 and 36 compartments.

[0056] According to one embodiment, all the compartments of the same box comprise the aforementioned insulating lining.

[0057] According to one embodiment, the peripheral compartments of at least one side of the heat-insulating box have a aforementioned insulating lining.

[0058] According to one embodiment, the peripheral compartments on two opposite sides of the heat-insulating box have a aforementioned insulating lining.

[0059] According to one embodiment, all the peripheral compartments of the heat-insulating box have the aforementioned insulating lining.

[0060] According to one embodiment, the plurality of compartments of the same heat-insulating box comprises annex compartments having insulating linings different from those of the aforementioned compartments, for example with compartments filled only with glass wool, rock wool, wadding or perlite. According to one embodiment, the central compartments of the plurality of compartments are annex compartments.

[0061] According to one embodiment, the block of fiber-reinforced polyurethane foam has a density greater than 70 kg.m3, advantageously greater than 90 kg.m3, preferably greater than 110 kg.m3, more preferably greater than 130 kg.m3.

[0062] Thanks to the aforementioned characteristics, compression tests have demonstrated an improvement of approximately 65% ​​in the compressive strength of the aforementioned heat-insulated boxes compared to conventional heat-insulated boxes in the field of sealed and thermally insulating tanks for storing liquefied gas.

[0063] According to one embodiment, the invention also provides a sealed and thermally insulating tank intended to contain a liquefied gas, the tank comprising a tank wall, the tank wall comprising: a thermally insulating barrier intended to be fixed to a supporting structure, and a sealed membrane fixed against the thermally insulating barrier, the thermally insulating barrier comprising a aforementioned heat-insulating box.

[0064] According to one embodiment of the tank, the tank wall comprises successively, in the direction of the thickness of the tank wall, from the outside to the inside of the tank, a secondary thermal insulation barrier retained on a supporting structure, a secondary waterproof membrane resting against the secondary thermal insulation barrier, a primary thermal insulation barrier resting against the secondary waterproof membrane and a primary waterproof membrane resting against the primary thermal insulation barrier and intended to be in contact with the liquefied natural gas contained in the tank.

[0065] According to one embodiment of the tank, the secondary thermal insulation barrier comprises the aforementioned heat-insulating box. According to one embodiment, the barrier secondary thermal insulation comprises a plurality of aforementioned heat-insulating boxes, preferably juxtaposed with each other.

[0066] Thanks to these characteristics, when the tank contains a liquefied gas such as LNG, the evaporation rate of the liquefied gas, better known by the English term "Boil-off rate" (BOR), is reduced. Indeed, fiber-reinforced polyurethane foam (RPUF) has excellent thermal performance at temperatures above - 110 °C, particularly superior to glass wool.

[0067] According to one embodiment of the tank, the primary thermal insulation barrier comprises the aforementioned heat-insulating box. According to one embodiment, the primary thermal insulation barrier comprises a plurality of aforementioned heat-insulating boxes, preferably juxtaposed with each other.

[0068] According to one embodiment of the tank, the tank comprises one or more of the characteristics of the sealed and thermally insulating tank described in document FR3110949 in which at least one of the secondary insulating blocks or at least one of the primary insulating blocks is replaced by a heat-insulating box mentioned above.

[0069] Such an installation may be part of a land-based or submerged storage facility, or may be installed in a floating, coastal or deep-water structure, including a ship, a floating storage and regasification unit (FSRU), a floating production and remote storage unit (FPSO) and the like. Such an installation may also serve as a fuel tank in any type of land vehicle or ship.

[0070] According to one embodiment, a ship for transporting a liquid gas, preferably LNG, comprises a double hull and a aforementioned tank arranged in the double hull.

[0071] According to one embodiment, the invention also provides a system for transferring a liquid gas, preferably LNG, the system comprising such a ship, insulated pipes arranged so as to connect the sealed and thermally insulating tank arranged in the hull of the ship to a floating or land-based storage facility and a pump for driving a flow of liquid gas, preferably LNG through the insulated pipes from or to the floating or land-based storage facility to or from the sealed and thermally insulating tank arranged in the hull of the ship.

[0072] According to one embodiment, the invention also provides a method for loading or unloading such a ship, in which the liquefied gas, preferably LNG, is conveyed through insulated pipes from or to a floating or land-based storage facility to or from the sealed and thermally insulating tank arranged in the hull of the ship. Brief description of the figures

[0073] The invention will be better understood, and other aims, details, characteristics and advantages thereof will appear more clearly during the following description of several particular embodiments of the invention, given solely for illustrative and non-limiting purposes, with reference to the appended drawings.

[0074] [Fig. 1] is a partial exploded and perspective view of a heat-insulating box whose insulating linings have been deliberately omitted, according to one embodiment.

[0075] [Fig.2] is an exploded and perspective view of the heat-insulating box of [Fig.l] with the insulating fittings.

[0076] [Fig. 3] is a sectional view along plane I of the heat-insulating box of [Fig. 2] when a compressive stress in the direction of the thickness of the box is exerted.

[0077] [Fig.4] is a sectional view along plane II-II of the heat-insulating box according to the embodiment of [Fig.2].

[0078] [Fig.5] is a sectional view similar to that of [Fig.4], of a heat-insulating box according to a second embodiment.

[0079] [Fig.6] is a sectional view similar to that of [Fig.5], of a heat-insulating box according to a third embodiment.

[0080] [Fig.7] is a sectional view similar to that of [Fig.6], of a heat-insulating box according to a fourth embodiment.

[0081] [Fig.8] is a cutaway schematic representation of a vessel's tank and a terminal for loading / unloading this tank.

[0082] [Fig.9] is a sealed and thermally insulating tank wall according to one embodiment.

[0083] [Fig. 10] is a sectional view similar to that of [Fig. 6], of a heat-insulating box according to another embodiment. Description of the embodiments

[0084] A heat-insulating box 1 according to a first embodiment is presented with figures 1 to 4.

[0085] The heat-insulating box 1 is for example made from wood and has the general shape of a rectangular parallelepiped.

[0086] The heat-insulating box 1 comprises a bottom panel 2 and a cover panel 3, for example made of plywood. The bottom panel 2 is located opposite and at a distance along a thickness direction E from the cover panel 3.

[0087] The cover panel 3 comprises two grooves 33 intended to receive welding supports in order to weld the primary waterproof membrane or the secondary waterproof membrane.

[0088] The distance between the bottom panel 2 and the cover panel 3 is maintained via four side panels 4 facing each other in pairs connecting the bottom panel 2 and the cover panel 3 along the edges of the bottom panel 2 and the cover panel 3 in order to form an interior space 5 of the heat-insulating box 1.

[0089] A plurality of internal partitions divide the interior space 5 into a plurality of compartments 6. The heat-insulating box, illustrated in Figures 1 to 4, has 28 compartments. The number of compartments may also be greater or less than 28 depending on the size of the desired heat-insulating box or the desired number of compartments.

[0090] The plurality of partitions is in contact against the bottom panel 2 and the cover panel 3 in order to obtain a high compressive strength in the thickness direction E of the heat-insulating box 1.

[0091] The plurality of internal partitions comprises a first series of rows parallel to a first side panel 7 and to a second side panel 8. Each row of the first series of rows comprises a continuous rigid partition 9 which extends from a third side panel 10 to a fourth side panel 11 which is located opposite the third side panel 10.

[0092] The plurality of internal partitions comprises a second series of rows perpendicular to the first row, i.e. the second series of rows is parallel to the third side panel 10 and the fourth side panel 11. Each row of the second series of rows comprises a plurality of interrupted rigid partitions 12 interposed in the spaces formed between two parallel rows of the first series of rows and in the spaces formed between a row of the first series of rows and the third side panel 10 or the fourth side panel 11.

[0093] According to an alternative embodiment, the continuous rigid partitions 9 of the first series of rigid partitions have a series of notches and the plurality of interrupted rigid partitions 12 is replaced by a plurality of continuous rigid partitions having a series of notches complementary to the first series of notches so that the first series of partitions and the second series of partitions are installed by fitting into the interior space 5 of the heat-insulating box 1. Such types of arrangement with notches are illustrated in the patent document FR2867831B1, in particular in its figures 2 to 5, 8 and 10.

[0094] Each of the compartments 6 of the heat-insulating box 1 comprises an insulating lining filling said compartment 6, that is to say that the insulating lining completely fills the compartment 6.

[0095] Each insulating lining comprises a block of foam 13 made of fiber-reinforced polyurethane foam which has the general shape of a rectangular parallelepiped and strips of compressible insulating material 20, for example strips of wool glass which are in a compressed state.

[0096] At least 60% of the fibers of the foam block 13 extend in directions whose angle with the bottom panel 2 is approximately 90°. Thanks to such a fiber orientation, the heat-insulating box 1 has an increased compressive strength capacity in the direction of the thickness of the heat-insulating box 1 as visible in [Fig. 3] which represents the heat-insulating box 1 on which a compressive force is exerted on the cover panel 3. It can be seen in [Fig. 3] that the foam blocks 13 have a structural function in that they contribute to absorbing the compressive forces exerted in the direction of thickness of the heat-insulating box 1.

[0097] The foam block 13 is located in the center of the compartment 6 and four strips of compressible insulating material, such as glass wool, are respectively positioned and arranged in the compressed state, against the four lateral faces of the foam block 13. The four lateral faces of the foam block 13 are entirely covered laterally by the four strips.

[0098] In other words, the strips comprise a first strip 14 of compressible insulating material which is arranged in the compressed state and covers a first face of the foam block 13, a second strip 15 of compressible insulating material, which is arranged in the compressed state and covers a second face of the foam block 13, a third strip of compressible insulating material, which is arranged in the compressed state and covers a third face of the foam block 13 and a fourth strip 17 of compressible insulating material, which is arranged in the compressed state and covers a fourth face of the foam block 13.

[0099] As can be seen in particular in [Fig.2] the plurality of compartments comprises peripheral compartments which are adjacent to at least one of the side panels including four peripheral corner compartments 61 which are located at the four corners of the heat-insulating box 1.

[0100] Each corner peripheral compartment 61 comprises the first strip 14 and the second strip 15 which are respectively interposed between the first and second surfaces of the foam block 13 and a side panel. The third strip 16 is interposed between the third surface of the foam block 13 and a continuous rigid partition 9. The fourth strip 17 is interposed between the fourth surface of the foam block 13 and an interrupted rigid partition 12.

[0101] In the embodiment shown, seven peripheral compartments 62 are adjacent with a single side panel, i.e. they each comprise a first strip of compressible insulating material 20 which is arranged in the compressed state and located between a side panel and the foam block 13 and either: - a second and a third strip of compressible insulating material which are arranged in the compressed state and respectively interposed between the foam block 13 and two continuous rigid partitions 9, as well as a fourth strip of compressible insulating material which is arranged in a compressed state and interposed between the foam block 13 and an interrupted rigid partition 12; or - a second and a third strip of compressible insulating material which are arranged in the compressed state and respectively interposed between the foam block 13 and two interrupted rigid partitions 12, as well as a fourth strip of compressible insulating material which is arranged in the compressed state and interposed between the foam block 13 and a continuous rigid partition 9.

[0102] As can be seen in particular in [Fig.2], the plurality of compartments 6 further comprises central compartments 63 each delimited by two continuous rigid partitions 9 and two interrupted rigid partitions 12. Thus, a first and a second strip of compressible insulating material 20 are respectively interposed between the foam block 13 and a first and a second rigid partition 9, and a third and a fourth strip of compressible insulating material are respectively interposed between the foam block 13 and a first and a second interrupted rigid partition 12.

[0103] For figures 5, 6 and 7, elements identical or similar to those illustrated in figures 1 to 4 will not be systematically described again, they bear the same reference number incremented by 100 per embodiment.

[0104] The alternative embodiment of the heat-insulating box 101, shown in [Fig. 5], differs from the embodiment shown with Figures 1 to 4 in that each side panel 107, 108, 110, 111 of the peripheral compartments 161 and 162 is in direct contact with the foam block 113, that is to say that there are no strips of compressible insulating material 120 between the foam block 113 of the peripheral compartments 161 and 162 and the corresponding side panel. Thus, the phenomenon of buckling of the side panels 107, 108, 110, 111 in a situation of compression of the heat-insulating box 101 is greatly reduced.

[0105] The variant embodiment of the heat-insulating box 201, shown in [Fig. 6], differs from the embodiment shown in Figures 1 to 4 in that the insulating lining of the compartments is arranged according to a set of compartments defined according to diagrams (a), (b), (c) and (d), as shown in [Fig. 6].

[0106] The compartment according to (a) and the compartment according to (c) are adjacent to the compartments according to (b) and (c). The set of four compartments has a general shape of a rectangle according to the sectional view illustrated in [Fig.6].

[0107] The four compartments of the assembly each have two strips of compressible insulating material 220 positioned against two adjacent surfaces of the block of fiber-reinforced polyurethane foam 213.

[0108] The two strips of each compartment are arranged in such a way that, for two compartments adjacent to each other along a translation direction parallel to the X or Y axis, the two bands of one of the two compartments correspond to the image of the two bands of the other compartment obtained by the combination of a symmetry along an axis parallel to the translation direction and passing through the center of the compartment and a translation along the translation direction.

[0109] In other words, each of the two strips of compressible insulating material 220 of each compartment of the set of four compartments is positioned between the foam block 213 and either: - the side wall, the continuous rigid partition 209 or the interrupted rigid partition 212, so as not to be positioned against a common partition, for example the same continuous rigid partition 209; and / or - the same discontinuous rigid partition 212.

[0110] In other words, the two strips of compressible insulating material 220 of compartment (a) are not positioned against the same partition, for example the discontinuous rigid partition 212 or continuous rigid partition 209, as the two strips of compartment (b) and (c).

[0111] The two strips of compartment (b) are not positioned against the same partition as the two strips of compartment (a) and (d).

[0112] The two strips of compartment (c) are not positioned against the same partition as the two strips of compartment (a) and (d).

[0113] The two strips of compartment (d) are not positioned against the same partition as the two of compartment (c) and (b).

[0114] The variant embodiment of the heat-insulating box 401, shown in [Fig. 10], differs from the embodiment shown in [Fig. 6] in that the compartments marked “N”, i.e. certain peripheral compartments 462, and the central compartments 463, are annex compartments having insulating linings different from those of the compartments according to (a) or (c), with, for example, “N” compartments filled with glass wool, wadding or perlite.

[0115] According to a variant of [Fig. 10] which is not illustrated, only the central compartments are annex compartments, the peripheral compartments being compartments having the aforementioned characteristics, for example according to diagrams (a), (b), (c) and (d).

[0116] The variant embodiment of the heat-insulating box 301, shown in [Fig. 7], differs from the embodiment shown in FIGS. 1 to 4 in that the insulating lining comprises four foam blocks 313 made of fiber-reinforced polyurethane foam, each of which is arranged in a respective corner of the same compartment 306.

[0117] The four foam blocks 313 of the same compartment 306 are respectively spaced from each other via three strips of compressible insulating material 220, in cross shape in the embodiment of [Fig.7]. A first strip crosses the width at the center of the compartment 306 and two strips perpendicular to the first strip and are located opposite each other and spaced from each other by the first strip.

[0118] This arrangement of the insulating lining is repeated on all of the compartments 306 of the heat-insulating box 301 as illustrated in [Fig.7].

[0119] According to a variant not shown, the four foam blocks 313 of the same compartment 306 are respectively spaced from each other via four strips of compressible insulating material 220 forming a cross in a manner similar to that illustrated in [Fig.7].

[0120] The heat-insulating boxes presented above are intended to be integrated into a sealed and thermally insulating tank intended to contain a liquefied gas such as LNG.

[0121] In relation to [Fig.9], the multi-layer structure of a sealed and thermally insulating tank is described.

[0122] Such a tank generally has a secondary thermal insulation barrier 30 retained on a supporting structure (not shown in [Fig.9]), a secondary waterproof membrane 31 resting against the secondary thermal insulation barrier 30, a primary thermal insulation barrier 32 resting against the secondary waterproof membrane 31 and a primary waterproof membrane 33 resting against the primary thermal insulation barrier 32 and intended to be in contact with the liquefied natural gas contained in the tank, the heat-insulating boxes presented above being integrated into the secondary thermal insulation barrier and / or into the secondary thermal insulation barrier.

[0123] According to one embodiment, the secondary thermal insulation barrier 30 comprises a plurality of heat-insulating boxes, as described above, juxtaposed with each other.

[0124] According to one embodiment, the secondary thermal insulation barrier 30 comprises a plurality of aforementioned heat-insulating boxes and other heat-insulating boxes filled with glass wool or rock wool or perlite, which may have other characteristics than the aforementioned heat-insulating boxes.

[0125] According to one embodiment, the aforementioned heat-insulating boxes are preferably arranged in the tank at the level of at least part of the edges between faces of a tank and / or at the level of the ceiling of the tank.

[0126] According to one embodiment, the primary thermal insulation barrier 32 comprises a plurality of heat-insulating boxes, as described above, juxtaposed with each other.

[0127] According to one embodiment, the secondary waterproof membrane 31 comprises a continuous sheet of metal strakes with raised edges. The metal strakes are welded by their raised edges to parallel welding supports which are fixed in grooves 33 provided in cover panels 3 of the heat-insulating boxes as described above. The metal strakes are, for example, made of Invar ®: that is to say an alloy of iron and nickel whose coefficient of expansion is typically between 1.2.10-6 and 2.10-6 K1, or of iron alloy with a high manganese content whose coefficient of expansion is typically between 7.10-6 and 10.10-6 K1

[0128] Similarly, the primary waterproof membrane 33 comprises a continuous sheet of metal strakes with raised edges. The metal strakes are welded by their raised edges to parallel welding supports which are fixed in grooves 33 formed in cover panels 3 of the heat-insulating boxes as described above. The metal strakes are, for example, made of Invar®: that is to say an alloy of iron and nickel whose coefficient of expansion is typically between 1.2.10-6 and 2.10-6 K1, or of iron alloy with a high manganese content whose coefficient of expansion is typically between 7.10-6 and 10.10-6 K1.

[0129] With reference to [Fig.8], a cutaway view of a LNG carrier ship 70 shows a sealed and thermally insulating tank 71 of generally prismatic shape mounted in the double hull 72 of the ship. The wall of the tank 71 comprises a primary sealed barrier intended to be in contact with the liquefied gas such as LNG contained in the tank, a secondary sealed barrier arranged between the primary sealed barrier and the double hull 72 of the ship, and two insulating barriers arranged respectively between the primary sealed barrier and the secondary sealed barrier and between the secondary sealed barrier and the double hull 72.

[0130] In a manner known per se, loading / unloading pipes 73 arranged on the upper deck of the ship can be connected, by means of appropriate connectors, to a maritime or port terminal to transfer a cargo of liquefied gas such as LNG from or to the tank 71.

[0131] [Fig. 8] shows an example of a marine terminal comprising a loading and unloading station 75, a subsea pipeline 76 and an onshore installation 77. The loading and unloading station 75 is a fixed offshore installation comprising a movable arm 74 and a tower 78 which supports the movable arm 74. The movable arm 74 carries a bundle of insulated flexible pipes 79 which can be connected to the loading / unloading pipelines 73. The orientable movable arm 74 adapts to all sizes of LNG carriers. A connecting pipeline not shown extends inside the tower 78. The loading and unloading station 75 allows the loading and unloading of the LNG carrier 70 from or to the installation on land 77. This comprises liquefied gas storage tanks 80 and connecting pipes 81 connected by the underwater pipe 76 to the loading or unloading station 75. The underwater pipe 76 allows the transfer of liquefied gas between the loading or unloading station 75 and the on-shore installation 77 over a long distance, for example 5 km, which makes it possible to keep the LNG carrier 70 at a great distance from the coast during loading and unloading operations.

[0132] To generate the pressure necessary for the transfer of the liquefied gas, pumps on board the ship 70 and / or pumps equipping the onshore installation 77 and / or pumps equipping the loading and unloading station 75 are used.

[0133] Although the invention has been described in connection with several particular embodiments, it is clearly not limited thereto and includes all technical equivalents of the means described as well as their combinations if they fall within the scope of the invention as defined by the claims.

[0134] The use of the verb “comprise” or “include” and its conjugated forms does not exclude the presence of other elements or other steps than those stated in a claim.

[0135] In the claims, any reference sign in parentheses shall not be construed as limiting the claim.

Claims

Claims

1. A heat-insulating box for a sealed and thermally insulating tank intended to contain a liquefied gas, the heat-insulating box (1, 101, 201, 301, 401) comprising: a cover panel (3) and a bottom panel (2) spaced apart along a thickness direction of the cover panel; side panels (7, 8, 10, 11) connecting the bottom panels and the cover panels along the edges of the bottom panel and the cover panel in order to form an interior space (5);a plurality of internal partitions (9, 12) dividing said interior space into a plurality of compartments (6, 61, 62, 63), a first compartment of the plurality of compartments comprising an insulating lining filling said first compartment, the insulating lining comprising a foam block (13, 113, 213, 313, 413) which is made of fiber-reinforced polyurethane foam and which extends from the bottom panel to the cover panel so as to take up the compressive forces exerted on the cover panel in the thickness direction (E) and a first strip (14) of compressible insulating material which covers a lateral surface of the foam block (13, 113, 213, 313, 413), is arranged in a compressed state and is capable of relaxing in order to compensate for the contraction of the foam block (13, 113, 213, 313, 413).;

2. A heat-insulating box according to claim 1, wherein the plurality of internal partitions are in contact against the bottom panel and the cover panel.

3. A heat-insulating box according to claim 1 or 2, the fibers of the foam block are in the form of a plurality of fiber mats, each of the fiber mats extending along a plane forming an angle with the bottom panel of between 80° and 100°.

4. Heat-insulating box according to one of claims 1 to 3, the insulating lining comprises a second strip (15) of compressible insulating material in the compressed state covering a second lateral face of the foam block.

5. Heat-insulating box according to claim 4, the insulating lining comprises a third strip (16) of compressible insulating material in the compressed state covering a third lateral face of the foam block.

6. Heat-insulating box according to claim 5, the insulating lining comprises a fourth strip (17) of compressible insulating material in the compressed state covering a fourth lateral face of the foam block, the first, second, third and fourth strips forming a lateral envelope laterally surrounding the foam block.

7. A heat-insulating box according to one of claims 1 to 6, wherein the insulating lining comprises four blocks of fiber-reinforced polyurethane foam which are each arranged in a respective corner of the compartment, the four foam blocks being respectively spaced from each other via a plurality of strips of compressible insulating material in the compressed state, the plurality of strips comprising the first strip.

8. Heat-insulating box according to one of claims 1 to 7, in which the plurality of compartments comprises: - peripheral compartments (61, 62, 161, 162, 261, 262, 361, 362, 462) adjacent to at least one of the side panels;- central compartments (63, 163, 263, 363, 463) delimited by internal partitions of the plurality of internal partitions, the first compartment being one of the central compartments, the peripheral compartments and the central compartments each comprising an insulating lining filling said peripheral compartments and said central compartments, the insulating lining comprising a block of fiber-reinforced polyurethane foam extending from the bottom panel to the cover panel so as to take up the compressive forces exerted on the cover panel in the thickness direction and a first strip of compressible insulating material in the compressed state and covering a lateral surface of the foam block and capable of relaxing in order to compensate for the contraction of the foam block.;

9. A heat-insulating box according to claim 8, wherein each side panel of the peripheral compartments is in direct contact with the foam block.

10. Heat-insulating box according to claim 8 or 9, in which the insulating lining of each central compartment comprises four strips of compressible insulating material in the compressed state interposed respectively between the internal partitions and the foam block.

11. A heat-insulating box according to one of claims 1 to 6, wherein the plurality of compartments comprises a set of compartments formed by the first compartment (a) which is adjacent to a second compartment (b) and a third compartment (c), as well as a fourth compartment (d) which is adjacent to the second compartment (b) and to the third compartment (c), the first compartment comprising: the first compressed strip between the first lateral face of the foam block and a first internal partition which separates the first compartment and the second compartment, a second strip of compressible insulating material in the compressed state between a second lateral face of the foam block adjacent to the first lateral face and a second internal partition which separates the first compartment and the third compartment, the second compartment comprising: a first strip of compressible insulating material in the compressed state between a first lateral face of a second block of fiber-reinforced polyurethane foam and a third internal partition,a fourth strip of compressible insulating material in the compressed state between a fourth lateral face of the second block of foam and a first lateral panel, the third compartment comprising: a second strip of compressible insulating material in the compressed state between a second lateral face of a third block of fiber-reinforced polyurethane foam and a fourth internal partition, a third strip of compressible insulating material in the compressed state between a third lateral face of the third block of foam and a second lateral panel, the fourth compartment comprising: a fourth strip of compressible insulating material in the compressed state between a fourth lateral face of a fourth block of fiber-reinforced polyurethane foam and an internal partition which separates the fourth compartment and the third compartment,a third compressed strip between a third lateral face of the fourth foam block and an internal partition which separates the fourth compartment and the second compartment.,

12. A sealed and thermally insulating tank intended to contain a liquefied gas, the tank (71) comprising a tank wall, the tank wall comprising: a thermally insulating barrier (30, 32) intended to be fixed to a supporting structure, and a sealed membrane (31, 33) fixed against the thermally insulating barrier, the thermally insulating barrier comprising a heat-insulating box according to one of claims 1 to 11.

13. Vessel (70) for transporting a cold liquid product, the vessel comprising a double hull (72) and a tank (71) according to claim 12 arranged in the double hull.

14. A method of using a ship (70) according to claim 13, wherein the liquefied gas is routed through insulated conduits (73, 79, 76, 81) from or to a floating or land storage facility (77) to or from the tank (71) of the ship (70) to effect loading or unloading of the ship.

15. A transfer system for a cold liquid product, the system comprising a ship (70) according to claim 13, insulated conduits (73, 79, 76, 81) arranged to connect the tank (71) installed in the hull of the ship to a floating or land storage facility (77) and a pump for driving a flow of cold liquid product through the insulated conduits from or to the floating or land storage facility to or from the tank of the ship.

Images