EP3924662A1

EP3924662A1 - Insulating block intended for thermally insulating a storage tank

Info

Publication number: EP3924662A1
Application number: EP20707743.9A
Authority: EP
Inventors: Pierre Montfort; Benjamin CHARPENTIER; Holger Frei
Original assignee: Gaztransport et Technigaz SA
Current assignee: Gaztransport et Technigaz SA
Priority date: 2019-02-14
Filing date: 2020-02-11
Publication date: 2021-12-22
Also published as: JP7418453B2; JP2022520096A; FR3092898B1; KR20210124996A; CA3128100A1; CN113423988B; CN113423988A; FR3092898A1; US20220136653A1; WO2020165537A1

Abstract

The invention relates to an insulating block intended for thermally insulating a fluid storage tank comprising: - a first plate (11) and a second plate, parallel to one another, spaced along a direction of the thickness of the insulating block; - bearing pillars inserted between the first and second plates (10, 11) along the direction of the thickness of the insulating block; and - a heat-insulated lining arranged between the bearing pillars; - the first plate (11) comprising reinforced bearing zones (13) against which the bearing pillars (12) press, the reinforced bearing zones (13) being connected to one another by a network of ribs (18).

Description

Title of the invention: Insulating block for insulation

thermal of a storage tank

Technical area

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

[0002] Tight 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 may be intended for the transport of liquefied natural gas or to receive liquefied natural gas serving as fuel for the propulsion of the floating structure.

Technological background

[0003] Document WO2016097578 discloses a sealed and thermally insulating tank for the storage of liquefied natural gas comprising tank walls fixed to a supporting structure, such as the double hull of a ship. Each tank wall successively comprises, in the direction of thickness, from the outside to the inside of the tank, a secondary thermally insulating barrier anchored to the supporting structure, a secondary waterproofing membrane resting against the thermally insulating barrier secondary, a primary thermally insulating barrier resting against the secondary waterproofing membrane and a primary waterproofing membrane which rests against the secondary thermally insulating barrier and is intended to be in contact with the liquefied natural gas stored in the vessel.

[0004] The secondary and primary thermally insulating barriers comprise insulating blocks which are juxtaposed next to each other. The insulation blocks have a bottom plate and a cover plate, parallel to each other, and supporting pillars that extend in the thickness direction of the insulation block between the bottom plate and the cover plate . The insulating blocks further include an insulating lining which is disposed between the supporting elements.

In the embodiment illustrated in Figures 1 1 to 13 of the above-mentioned document WO2016097578, the insulating blocks include load distribution structures. Given the fact that the supporting pillars are intended to take up a load hydrostatic and hydrodynamic in order to transmit it from the cover plate of the insulating block to the supporting structure, such load distribution structures make it possible to avoid the punching phenomena liable to exist in the event of excessive concentration of the compressive stresses. The load distribution structures are interposed between the pillars and the cover plate, on the one hand, and between the pillars and the base plate, on the other hand.

[0006] The cover and bottom panels have a substantial thickness so as to ensure a bending stiffness of the insulating blocks which is sufficient to limit their bending, in particular when they are subjected to thermal gradients. However, in return for the mechanical stiffening effect, the large thickness of the cover and bottom plates has the effect of degrading the thermal insulation performance of the insulating blocks and increasing their mass.

[0007] The aforementioned insulating blocks are therefore not fully satisfactory.

summary

An idea at the basis of the invention is to provide an insulating block of the aforementioned type, intended for the thermal insulation of a storage tank of a fluid which offers an excellent compromise between, on the one hand, high rigidity, and on the other hand, effective thermal insulation.

[0009] For this, according to one embodiment, the invention provides an insulating block intended for the thermal insulation of a fluid storage tank comprising:

- a first plate and a second plate parallel, spaced in a direction of thickness of the insulating block;

- supporting pillars interposed between said first and second plates in the direction of thickness of the insulating block; and

- a heat-insulating lining arranged between the supporting pillars;

- the first plate being molded in a composite material comprising a polymer matrix reinforced by fibers and comprising reinforced bearing zones against which the supporting pillars bear, the reinforced bearing zones being separated from each other by zones thinned and having a greater thickness than that of the thinned zones, the reinforced bearing zones being connected to each other by a network of ribs.

[0010] Thus, the ribs make it possible to reinforce the flexural rigidity of the first plate between the thicker bearing zones against which the pillars bear. This allows a reduction in the thickness of the first plate between the support zones. From then, the mass of the insulating block is reduced, its thermal insulation performance improved, while obtaining sufficient rigidity of the insulating block.

[001 1] According to embodiments, such an insulating block may include one or more of the following characteristics.

[0012] According to one embodiment, the insulating block comprises reinforced support zones aligned in rows parallel to a longitudinal direction and the network of ribs comprises ribs each extending between two of the adjacent reinforced support zones of one of the rows.

[0013] According to one embodiment, the insulating block comprises reinforced support zones aligned in columns parallel to a transverse direction and the network of ribs comprises ribs each extending between two of the adjacent reinforced support zones of one of the columns.

[0014] According to one embodiment, the network of ribs has two axes of symmetry perpendicular to each other.

[0015] According to one embodiment, the transverse direction is orthogonal to the longitudinal direction.

[0016] According to one embodiment, the network of ribs comprises ribs each extending between two reinforced support zones aligned in a direction secant to longitudinal and transverse directions.

[0017] According to one embodiment, each rib has a shape chosen from a rectilinear shape, a curvilinear shape and an Omega shape.

[0018] According to one embodiment, the network of ribs comprises connecting ribs which each connect two ribs which each extend between two reinforced support zones.

[0019] According to one embodiment, the network of ribs comprises edge ribs each extending along one of the edges of the first plate and the edge ribs are each connected by ribs to one or more of the zones reinforced support.

[0020] According to one embodiment, the heat-insulating lining is an insulating polymer foam which adheres to the first plate and to the second plate. This makes it possible to increase the resistance of the insulating block to the shear forces exerted between the first plate and the second plate and thus to oppose the tilting of the supporting pillars. [0021] According to one embodiment, the insulating polymer foam further adheres to the supporting pillars. This further contributes to increasing the resistance of the insulating block to mechanical stresses.

According to one embodiment, the heat-insulating lining is obtained by molding insulating polymer foam between the first plate and the second plate. The foam thus obtained is particularly advantageous in that it makes it possible to obtain in a simple manner an adaptation of the geometry of the heat-insulating lining to a complex geometry of the first plate, in particular when the latter comprises a network of ribs.

[0023] According to another variant embodiment, the insulating polymer foam is prefabricated in the form of one or more pre-cut blocks which have orifices to accommodate the supporting pillars and complementary cutouts of the network of ribs.

[0024] According to one embodiment, the heat-insulating lining is a polyurethane foam, optionally reinforced with fibers. According to a particular embodiment, the polyurethane foam reinforced with fibers has a density of the order of 20 to 40 kg / m 3. According to one embodiment, the reinforced polyurethane foam has a fiber content of between 3 and 5% by mass.

[0025] According to one embodiment, the fibers of the heat-insulating lining are chosen from glass fibers, carbon fibers, aramid fibers and mixtures thereof.

[0026] According to one embodiment, at least one of the reinforced bearing zones has an interlocking element which cooperates by form-fitting with one end of one of the supporting pillars. According to one embodiment, the interlocking element is a female element, such as a sleeve, in which the end of the supporting pillar is fitted. In another embodiment, the interlocking element is a male element which is inserted inside a hollow end of the supporting pillars.

[0027] According to one embodiment, the first plate is produced by thermoforming a thermoplastic matrix reinforced with a reinforcement of fibers chosen from mats, unidirectional (UD) or non-unidirectional (UD) plies and fabrics. The fiber reinforcement is, for example, glass fibers.

[0028] According to one embodiment, the thermoplastic matrix is, for example, chosen from polyethylene, polypropylene, polyethylene terephthalate, polyamide, polyoxymethylene, polyetherimide, polyacrylate and copolymers thereof. [0029] According to one embodiment, the fibers are chosen from glass fibers, carbon fibers, aramid fibers, flax fibers, basalt fibers and mixtures thereof.

According to one embodiment, the supporting pillars are made of a composite material comprising a polymer matrix reinforced with fibers, the supporting pillars having a longitudinal direction oriented in the direction of thickness of the insulating block, more than 50% of fibers of the supporting pillars being oriented parallel to the longitudinal direction of the supporting pillars or inclined at an angle of less than 45 ° with respect to said longitudinal direction. This is particularly advantageous for giving the supporting pillars a satisfactory compressive strength.

The bearing pillar fibers are chosen from glass fibers, carbon fibers, aramid fibers, basalt fibers and their derivatives and mixtures thereof.

[0032] According to one embodiment, the supporting pillars are produced by pultrusion, which is advantageous for obtaining a privileged orientation of the fibers along the direction of extrusion of the fibers and of the hollow shapes.

[0033] According to one embodiment, the supporting pillars are hollow and lined with a heat-insulating lining.

According to one embodiment, the second plate is molded in a composite material comprising a polymer matrix reinforced by fibers and comprising reinforced bearing zones against which the bearing pillars bear, the reinforced bearing zones being separated from each other by thinned areas and having a greater thickness than that of the thinned areas, the reinforced bearing areas being connected to each other by a network of ribs.

The second plate is likely to have one or more of the characteristics presented above in relation to the first plate.

[0036] According to one embodiment, the first plate and the second plate are identical

[0037] According to one embodiment, the first plate is a cover plate and the second plate is a bottom plate.

[0038] According to one embodiment, the invention also provides a sealed and thermally insulating tank for storing a fluid comprising a thermal insulation barrier comprising a plurality of the aforementioned insulating blocks juxtaposed, and a waterproofing membrane resting against the thermal insulation barrier. Such a tank can be made with a single waterproofing membrane or with two alternating waterproofing membranes with two thermal insulation barriers.

[0039] Such a tank can be part of an onshore storage facility, for example for storing LNG or be installed in a floating, coastal or deep-water structure, in particular an LNG vessel, an LNG propelled vessel, a unit floating storage and regasification (FSRU), a floating production and remote storage unit (FPSO) and others.

[0040] According to one embodiment, a vessel for transporting a fluid comprises a double hull and an above-mentioned tank arranged in the double hull.

According to one embodiment, the invention also provides a method for loading or unloading such a vessel, in which a fluid is conveyed through isolated pipes from or to a floating or terrestrial storage installation to or from the vessel's tank.

[0042] According to one embodiment, the invention also provides a transfer system for a fluid, the system comprising the aforementioned vessel, isolated pipes arranged so as to connect the tank installed in the hull of the vessel to a storage facility floating or land-based storage facility and a pump for driving fluid through insulated pipelines from or to the floating or land-based storage facility to or from the vessel's vessel.

Brief description of the figures

The invention will be better understood, and other aims, details, characteristics and advantages thereof will emerge more clearly during the following description of several particular embodiments of the invention, given solely by way of illustration. and not limiting, with reference to the accompanying drawings.

[0044] [fig.1] Figure 1 is a cutaway perspective view of a tank wall according to one embodiment.

[0045] [fig.2] Figure 2 is a schematic sectional view of an insulating block.

[0046] [Fig.3] Figure 3 illustrates an in-situ polymer foam injection molding process between the cover plate and the bottom plate of an insulating block.

[0047] [fig.4] Figure 4 is a view of the face of the cover plate of an insulating block which is facing the bottom plate.

[0048] [fig.5] Figure 5 is a detailed view of the cover plate of Figure 4. [0049] [fig.6] Figure 6 is a cutaway schematic representation of an LNG vessel tank and a loading / unloading terminal of this tank.

[0050] [Fig.7] Figure 7 is a schematic representation of a cover plate illustrating a network of ribs according to an alternative embodiment.

[0051] [Fig.8] Figure 8 is a schematic representation of a cover plate illustrating a network of ribs according to an alternative embodiment.

[0052] [Fig.9] Figure 9 is a schematic representation of a cover plate illustrating a network of ribs according to an alternative embodiment.

[0053] [Fig.10] Figure 10 is a schematic representation of a cover plate illustrating a network of ribs according to an alternative embodiment.

[0054] [Fig.1 1] Figure 1 1 is a schematic representation of a cover plate illustrating a network of ribs according to an alternative embodiment.

[0055] [fig.12] Figure 12 is a schematic representation of a cover plate illustrating a network of ribs according to an alternative embodiment.

[0056] [Fig.13] Figure 13 is a schematic representation of a cover plate illustrating a network of ribs according to an alternative embodiment.

[0057] [Fig.14] Figure 14 is a schematic representation of a cover plate illustrating a network of ribs according to an alternative embodiment.

[0058] [Fig.15] Figure 15 is a schematic representation of a cover plate illustrating a network of ribs according to an alternative embodiment.

[0059] [Fig.16] Figure 16 is a schematic representation of a cover plate illustrating a network of ribs according to an alternative embodiment.

[0060] [Fig.17] Figure 17 is a schematic representation of a cover plate illustrating a network of ribs according to an alternative embodiment.

[0061] [Fig.18] Figure 18 is a schematic representation of a cover plate illustrating a network of ribs according to an alternative embodiment.

[0062] [Fig.19] Figure 19 is a schematic representation of a cover plate illustrating a network of ribs according to an alternative embodiment.

[0063] [fig.20] Figure 20 is a schematic representation of a cover plate illustrating a network of ribs according to an alternative embodiment.

Description of embodiments In Figure 1, a wall of a sealed and thermally insulating tank is shown. The general structure of such a tank is well known and has a polyhedral shape. We will therefore only attempt to describe a wall zone of the tank, it being understood that all the walls of the tank can have a similar general structure. The wall of the tank comprises, from the outside towards the inside of the tank, a supporting wall 1, a secondary thermally insulating barrier 2 which is formed of insulating blocks 3, self-supporting, juxtaposed on the supporting structure 1 and anchored to that here by secondary retaining members 4, a secondary waterproofing membrane 5 carried by the insulating blocks 3, a primary thermally insulating barrier 6 formed of insulating blocks 7, self-supporting, juxtaposed and anchored on the secondary waterproofing membrane 5 by primary retaining members 8 and a primary sealing membrane 9, carried by the insulating blocks 7 and intended to be in contact with the cryogenic fluid contained in the vessel.

The supporting structure comprises a plurality of supporting walls 1 defining the general shape of the tank. The supporting structure can in particular be formed by the hull or the double hull of a ship. The supporting wall 1 can in particular be a self-supporting metal sheet or, more generally, any type of rigid partition having appropriate mechanical properties.

The primary 9 and secondary 5 waterproofing membranes are, for example, made up of a continuous layer of metal strakes with raised edges, said strakes being welded by their raised edges on parallel welding supports held on the insulating blocks 3, 7. The metal strakes are, for example, made of Invar ®, that is to say an alloy of iron and nickel, the coefficient of expansion of which is typically between 1, 2.10 ⁶ and 2.10 ⁶ K ^'1 , or in an iron alloy with a high manganese content, the coefficient of expansion of which is typically of the order of 7 to 9.10 ⁶ K ^{~ 1} . In the case of a vessel's tank, the strakes are preferably oriented parallel to the longitudinal direction of the vessel.

The secondary insulating blocks 3 and the primary insulating blocks 7 can have identical or different structures.

The secondary 3 and primary 7 insulating blocks have a rectangular parallelepiped shape defined by two large faces, or main faces, and four small faces, or side faces. According to one embodiment, the secondary 3 and primary 7 insulating blocks have the same length and the same width, the secondary insulating block 3 being however thicker than the primary insulating block 7. FIG. 2 is a schematic sectional view of the structure of an insulating block 3, 7 intended to form a secondary or primary insulating block. The insulating block 3, 7 comprises a bottom plate 10 and a cover plate 1 1 parallel, spaced in the direction of thickness of the insulating block 3, 7. The bottom plate 10 and the cover plate 1 1 define the faces main insulating block 3, 7.

The cover plate 1 1 has an outer support surface for receiving the secondary 5 or primary sealing membrane 9. The cover plate 1 1 further has grooves, not shown, for receiving welding supports making it possible to weld the metal strakes of the secondary 5 or primary 9 waterproofing membrane to each other. The grooves have an L-shape and are for example two in number per insulating block 3, 7. By convention, the longitudinal direction of the insulating block 3, 7 corresponds to the length of said insulating block 3, 7.

The insulating block 3, 7 comprises supporting pillars 12 extending in the thickness direction of the insulating block 3, 7. The supporting pillars 12 are supported, on the one hand, against the base plate 10 and , on the other hand, against the cover plate 1 1. The supporting pillars 12 allow the normal forces applied to the cover plate 1 1 to be transmitted to the base plate 10.

As shown, in Figures 4 and 5, the cover plate 11 comprises reinforced bearing areas 13 against which bear the supporting pillars 12. The reinforced bearing areas 13 have a thickness greater than that of the other areas of the cover plate 11, which will be referred to hereinafter by the term "thinned areas" 14. Note that the term "thinned" here has a relative meaning and means that the thinned areas 14 have a thickness less than that reinforced support zones 13. The reinforced support zones 13 make it possible to avoid the phenomena of excessive concentration of stresses in the zone of contact with the supporting pillars 12. For example, the thickness of the zones of reinforced support 13 of the cover plate 1 1 is between 15 and 35 mm, for example of the order of 25 mm while the thickness of the thinned areas 14 is between 1 and 10 mm, for example of the order from 2 to 4 mm.

Furthermore, according to one embodiment, the two ends of the supporting pillars 12 are respectively nested in a fitting element 15 formed in the cover plate 1 1 and in a fitting element formed in the base plate 10. The interlocking elements 15 can be of the female type, such as sleeves for example, in which the ends of the supporting pillars 12 engage by form assembly. Alternatively, the interlocking elements 15 are of the male type and fit inside the hollow ends of the supporting pillars 12.

In the embodiment shown in Figures 4 and 5, the interlocking elements 15 of the cover plate 11 are each formed by an annular rim formed in one of the reinforced bearing areas 13 of the plate cover 1 1. According to embodiments, the supporting pillars 12 are further fixed to the cover plate 1 1, for example by gluing. According to one embodiment, the interlocking elements 15 of the cover plate 11 and those of the bottom plate 10 have different structures.

Furthermore, the cover plate 1 1 comprises a network of ribs 16, in particular shown in Figures 4 and 5, connecting the reinforced bearing areas 13 to each other and intended to strengthen the bending rigidity of the panel cover. The network of ribs 16 thus makes it possible to limit the thickness of the cover plate 1 1 outside the reinforced bearing zones 13 against which the supporting pillars 12 bear, so as to reduce the mass of the insulating block 3, 7 and improve the thermal insulation performance of the insulating block 3, 7, while maintaining sufficient rigidity to the cover plate 1 1.

The insulating block 3, 7 also comprises a heat-insulating lining 17, in particular illustrated in Figure 2, which is disposed between the cover plate 1 1 and the bottom plate 10, in the spaces unoccupied by the supporting pillars 12.

Advantageously, the heat-insulating lining 17 is an insulating polymer foam, such as low density polyurethane foam reinforced with fibers. The insulating polymer foam is for example a polyurethane foam having a density of between 20 and 40 kg / m ³ , for example of the order of 35 kg / m ³ . The fiber content is advantageously between 3 and 5% by mass. The fibers are for example glass fibers but can also be carbon fibers, aramid fibers and mixtures thereof.

According to one embodiment, the insulating polymer foam is molded in-situ between the cover plate 1 1 and the bottom plate 10 in the spaces unoccupied by the supporting pillars 12. Thus, the insulating polymer foam adheres to the base plate 10, to the cover plate 1 1 and to the supporting pillars 12. Therefore, the insulating polymer foam increases the resistance of the insulating block 3, 7 to the shear forces exerted between the base plate 10 and the plate cover 1 1 of the insulating block 3, 7 and thus opposes the discharge of the supporting pillars 12. In addition, the injection molding of the insulating foam in-situ in an insulating block 3, 7 having a cover plate 1 1 having a complex geometry, as described above, is particularly advantageous in that it allows to obtain in a simple manner an adaptation of the geometry of the heat-insulating lining 17 to the complex geometry of the cover plate 11.

To do this, as shown in Figure 3, a preassembled structure composed of the cover plate 1 1, the bottom plate 10 and the supporting pillars 12 is arranged in a mold 18. The mold 18 has a cover 19 and a bottom 20 bearing respectively against the cover plate 11 and the bottom plate 10 of the insulating block 3, 7 and four peripheral walls 21, 22, two of which are shown in FIG. 3, which extend between the cover 19 and bottom 20 of mold 18 along the edges of bottom plate 10 and cover plate 11.

Furthermore, the mold 18 has one or more injection orifices 23 for pouring the insulating foam forming the heat-insulating lining 17, between the cover plate 1 1 and the bottom plate 10. As shown in Figure 3 When the injection orifice 23 is formed in the cover 19 of the mold 18, the cover plate 1 1 of the insulating block 3, 7 then has a corresponding orifice. According to another advantageous embodiment not shown, the injection orifice is formed in the bottom plate 10 of the insulating block 3, 7 which prevents degradation of the flat surface of the cover plate 1 1 intended for the support of 'a membrane.

According to another embodiment not shown, the mold 18 does not have a cover and the pre-assembled structure which is arranged in the mold has only one of the bottom plates 10 or cover 1 1 with the pillars carriers 12 partners. Said pre-assembled structure is arranged in the mold so that said bottom plate 10 or cover 1 1 is disposed against the bottom 20 of the mold 18. The other of the bottom plates 10 or cover 1 1 is attached against the supporting pillars 12 before the expansion of the foam reaches the base plate 10 or cover plate 1 1.

According to another embodiment, not shown, the insulating polymer foam is prefabricated in the form of one or more pre-cut blocks which have orifices to accommodate the supporting pillars 12 and complementary cutouts of the network of ribs 16 provided in the cover plate 1 1. The block of insulating polymer foam is advantageously glued to the cover plate 1 1 and to the bottom plate 10 so as to increase the resistance of the insulating block 3, 7 to mechanical forces, and in particular the shearing forces exerted between the bottom plate 10 and the cover plate 11 of the insulating block 3, 7 so as to oppose the discharge of the supporting pillars 12. In order to achieve a cover plate 1 1 having reinforced bearing areas 13 and a network of ribs 16, said cover plate 1 1 is advantageously obtained by molding a composite material having a reinforced polymer matrix by fibers.

According to one embodiment, the cover plate 1 1 is produced by a thermoforming process of a sheet of composite material, that is to say that the cover plate 11 is shaped to from a sheet of composite material by creeping said sheet of composite material under conditions of temperature, pressure and, optionally, under vacuum.

The cover plate 1 1 is, for example, made of a composite material commonly designated by the acronym GMT for "Glass fi ber Mat reinforced Thermoplastics" in the English language. A material of this type comprises a thermoplastic matrix reinforced with a reinforcement of fibers chosen from mats, unidirectional (UD) or non-unidirectional (UD) plies and fabrics. The fiber reinforcement is, for example, glass fibers. Such a material is intended to be hot pressed. Such materials have good mechanical strength and have, for example, a thermal conductivity of the order of 400 mW / m.K at 20 ° C.

The thermoplastic matrix is for example chosen from polyethylene, polypropylene, polyethylene terephthalate, polyamide, polyoxymethylene, polyetherimide, polyacrylate and copolymers thereof.

The fibers are chosen from glass fibers, carbon fibers, aramid fibers, flax fibers, basalt fibers and mixtures thereof.

According to another embodiment, the cover plate 1 1 is produced by a molding process of a composite material comprising fibers and a thermosetting matrix. The molding process is for example a compression molding of a composite material of the sheet molding mixture type designated by the acronym SMC for "Sheet Molding Compound" in English or of the bulk molding mixture type designated by the acronym BMC. for “Buik Molding Compound” in English.

The thermosetting matrix is for example chosen from polyester, vinyl ester, epoxy, polyurethane.

In addition, the fibers associated with the thermosetting matrix are of the same nature as those mentioned above in relation to the thermoplastic matrix, that is to say chosen from glass fibers, carbon fibers, aramid fibers, flax fibers, basalt fibers and mixtures thereof. According to variant embodiments, the reinforced bearing zones 13 and the network of ribs 16 are obtained by overmolding a composite material on a flat sheet of composite material.

According to one embodiment, the supporting pillars 12 are made of a composite material comprising fibers and a thermoplastic or thermosetting matrix by a pultrusion process. The supporting pillars 12 therefore have a tubular shape. The use of the pultrusion process is particularly advantageous in that it makes it possible to obtain a privileged orientation of the fibers in a direction parallel to the longitudinal direction of the supporting pillars 12. Also, advantageously, more than 50% of the fibers of the supporting pillars 12 are oriented parallel to the longitudinal direction of the supporting pillars 12 or inclined at an angle of less than 45 ° with respect to said longitudinal direction. This makes it possible to obtain satisfactory compressive strength without increasing the heat-conducting cross section of said supporting pillars 12. The fibers of the supporting pillars 12 are for example chosen from glass fibers, carbon fibers, aramid fibers, fibers. flax, basalt fibers and mixtures thereof.

As shown in Figures 2 and 3, such supporting pillars 12 having a hollow shape, the interior of said supporting pillars 12 is advantageously lined with a heat-insulating lining 24. The supporting pillars 12 are advantageously filled with heat-insulating lining before the supporting pillars 12 are not assembled to the cover plate

January 1 and the bottom plate 10, which avoids the presence of drilling such as to weaken said supporting pillars 12. Furthermore, according to one embodiment, the supporting pillars 12 are equipped with end pieces 25 which close both ends of the supporting pillars

12 and thus prevent the heat-insulating lining 24 placed inside said supporting pillars 12 from becoming detached from said supporting pillars 12. The end pieces 25 can in particular be glued to the ends of the supporting pillars 12 or inserted by force inside them. -this.

The heat-insulating lining 24 housed inside the supporting pillars 12 is for example an insulating polymer foam, such as polyurethane foam, which is molded in situ inside the supporting pillars 12. The insulating polymer foam can in particular be cast inside the supporting pillars 12 during their pultrusion, after their pultrusion, simultaneously or after the casting of the insulating polymer foam between the cover plates 1 1 and bottom 10. According to another variant embodiment, the heat-insulating lining 24 consists of a block of precut insulating polymer foam which is fitted inside each bearing pillar 12.

The reinforced bearing zones 13 as well as the network of ribs 16 are likely to have many different shapes. Advantageously, the network of ribs 16 has two axes of symmetry, namely an axis of symmetry parallel to the longitudinal axis x of the cover plate 1 1 and an axis of symmetry parallel to the transverse axis y of the plate cover 1 1.

In the embodiment shown in Figures 4 and 5, the supporting pillars 12 and, therefore, the reinforced bearing areas 13 are aligned along several rows r1, r2, two in the embodiment shown , extending parallel to the longitudinal direction x of the insulating block 3, 7. In addition, in this embodiment, the reinforced bearing zones 13 are also aligned along a plurality of columns c1, c2, ... s' extending parallel to the transverse direction y of the insulating block 3, 7. According to other embodiments, the supporting pillars 12 and the reinforced bearing zones 13 are distributed in staggered rows. In addition, in an advantageous embodiment, the supporting pillars 12 and the reinforced support zones 13 are distributed equidistantly.

In the embodiment shown in Figures 4 and 5, the cover plate 1 1 comprises a plurality of ribs 26, rectilinear, which extend parallel to the longitudinal direction x of the cover plate 1 1 and which connect, two by two, the reinforced support zones 13 adjacent to the same row r1, r2. The cover plate 1 1 also comprises ribs 27, rectilinear, which extend along the longitudinal edges of the cover plate 1 1 as well as ribs 28, rectilinear, which connect the reinforced bearing zones 13 arranged to the 'end of each of the rows r1, r2 to the adjacent transverse edge of the cover plate 1 1.

The cover plate 1 1 also comprises ribs 29, rectilinear, which extend transversely, that is to say perpendicular to the longitudinal direction x of the cover plate 1 1, and which connect two areas of '13 adjacent reinforced support of the same column c1, c2, ... The cover plate 1 1 also has ribs 30, rectilinear and parallel to the transverse direction y, which extend along the transverse edges of the plate cover 1 1 as well as rectilinear ribs 31 which connect the reinforced bearing zones 13, arranged at the end of each of the columns c1, c2, to the adjacent longitudinal edge of the cover plate 1 1.

[0100] Furthermore, the cover plate 1 1 comprises diagonal ribs 32 which connect each reinforced bearing zone 13 to a reinforced bearing zone 13 belonging to a column d, c2, ... and to an adjacent row r1, r2. In the illustrated embodiment, the diagonal ribs 32 intersect in a crossing zone 33 extending parallel to the longitudinal x direction of the cover plate 11. The cover plate 11 further comprises diagonal ribs 34 which extend parallel to the longitudinal direction x of the cover plate 11. extend parallel to the aforementioned diagonal ribs 32 and which each connect either one of the reinforced support zones 13 arranged at the end of one of the rows r1, r2 to the adjacent transverse edge or one of the reinforced support zones 13 arranged at the end of one of the columns c1, c2, ... at the adjacent longitudinal edge.

[0101] FIG. 7 schematically illustrates another arrangement of the ribs 26, 29, 32 and of the reinforced bearing zones 13. This embodiment differs from the embodiment described in relation to FIGS. 4 and 5 in that the ribs diagonals 32 are integrally rectilinear so that the intersection zone 33 between two intersecting diagonal ribs 32 does not have a portion extending parallel to the longitudinal direction x of the cover plate 11. It should also be noted that in the embodiment shown , the spacing between two adjacent rows r1, r2 is equal to the distance between two adjacent columns c1, c2, ... so that the diagonal ribs 32 are perpendicular to each other.

[0102] FIG. 8 schematically illustrates another arrangement of the ribs 26, 29, 32 and of the reinforced bearing zones 13. This embodiment differs from that described above in relation to FIG. 7 in that the zones d 'reinforced support 13 of the same row r1, r2 are not arranged equidistant from each other. Also, the diagonal ribs 32 are not necessarily perpendicular to each other.

The embodiment, shown in Figure 9, differs from that described above in relation to Figure 7 in that the reinforced bearing areas 13 belonging to a central column, referenced c2 in Figure 9, are not connected by a rib.

[0104] The embodiment illustrated in FIG. 10 differs from that described above in relation to FIG. 7, in particular in that the cover plate 11 does not have diagonal ribs 32 connecting each reinforced bearing zone 13 to an adjacent reinforced bearing zone 13 belonging to a row r1, r2 and to an adjacent column c1, c2, ... Furthermore, in this embodiment, the reinforced support zones 13 adjacent to the columns c1, arranged at the ends of the cover plate 11 are connected to each other by curvilinear ribs 35.

[0105] In the embodiment illustrated in FIG. 11, the ribs 36 which connect two by two the reinforced bearing zones 13 adjacent to the same row r1 are curvilinear. The cover plate 11 further comprises ribs 29, here rectilinear, which connect, two by two, the reinforced support zones 13 adjacent to the same column ci, c2. In addition, in this embodiment, the cover plate 1 1 is equipped with connecting ribs 37 which extend in the longitudinal direction x of the cover plate 1 1 between two rows r1, r2, adjacent and which thus connect the ribs 29.

In Figure 12, the cover plate 1 1 comprises ribs 26 which connect two by two the reinforced bearing areas 13 adjacent to the same row r1, r2 as well as ribs 29 which connect two by two the adjacent reinforced bearing zones 13 of the same column c1, c2, .... In addition, the adjacent reinforced bearing zones 13 of the same row r1, r2 are here connected two by two by a rib 38 in form of Omega. The Omega-shaped ribs 38 connecting the reinforced support zones 13 adjacent to the same row r1, r2 may or may not be connected to the Omega-shaped ribs 38 of the reinforced support zones 13 of the row r1, adjacent r2.

In Figure 13, the cover plate 1 1 comprises curvilinear ribs 39 which each connect two reinforced bearing areas 13 of the same column c1, c2 and are each granted to the curvilinear rib 39 connecting the two areas reinforced support 13 with an adjacent column c1, c2, ... In addition, the cover plate 1 1 also includes a rib 29, optional, which connects the two reinforced support areas 13 of a central column, referenced c2 in Figure 13.

[0108] Figure 14 shows a cover plate 1 1 according to an alternative embodiment.

In this figure, the cover plate 1 1 has only four reinforced support zones 13. However, according to other possible variants, the cover plate 1 1 has a greater number of reinforced support zones 13, the pattern presented in figure 14 repeating several times. In this embodiment, the cover plate 1 1 comprises ribs 26, rectilinear, which connect the reinforced support zones 13 adjacent to each row r1, r2. The cover plate 1 1 further comprises ribs 29, rectilinear, which connect the reinforced bearing zones 13 adjacent to each column c1, c2, ... Finally, the cover plate 1 1 here comprises a connecting rib 40 which extends transversely between two ribs 26 of longitudinal orientation.

In Figure 15, the cover plate 1 1 comprises ribs 26 which connect the reinforced bearing areas 13 adjacent to each row r1 and transverse ribs which connect the reinforced bearing areas 13 adjacent to the columns arranged to ends of the cover plate 1 1. Furthermore, the cover plate 1 1 further comprises diagonal ribs 41, here rectilinear, which each connect the reinforced bearing zone 13 of a first row r1, r2, arranged at proximity from a first end of the cover plate 1 1, to the reinforced bearing zone 13 of a second row arranged near a second opposite end of the cover plate 1 1. Furthermore, in FIG. 15 , the cover plate 1 1 comprises other diagonal ribs 42, optional, which each connect the reinforced bearing zone 13 of a row r1, r2 which is arranged near one end of the cover plate 1 1 to a support zone reinforced with a row r1, r2 and a column c1, c2, ... adjacent.

[01 10] In relation to FIGS. 16 to 20, other variant embodiments are described below in which the arrangement of the supporting pillars 12 and therefore of the reinforced support zones 13 is different from the arrangements mentioned above , in particular in that said reinforced support zones 13 are not all arranged in the form of columns and rows.

[01 1 1] In the embodiment illustrated in Figure 16, the reinforced bearing zones 13 are aligned along two rows r1, r2 extending parallel to the longitudinal direction x of the insulating block 3, 7. In furthermore, the reinforced bearing zones 13 are also aligned along a plurality of columns c1, c2, ..., here four, extending parallel to the transverse direction y of the insulating block 3, 7. Furthermore, the cover 1 1 has a central reinforced bearing zone 43 which is arranged in the center of the cover plate 1 1. The cover plate 1 1 comprises ribs 26, here rectilinear, which extend parallel to the longitudinal direction x of the cover plate 1 1 and which connect, two by two, the reinforced bearing zones 13 of the same row c1, c2. The cover plate 1 1 further comprises two ribs 29 which extend parallel to the transverse direction y and which connect in pairs the reinforced bearing areas 13 of the two columns arranged at the ends of the cover plate 1 1. Finally , the cover plate 1 1 comprises radial ribs 44 which connect the central reinforced bearing zone 43 to each of the other reinforced bearing zones 13.

[01 12] In the embodiment illustrated in Figure 17, the cover plate 1 1 has four reinforced bearing areas 13 outer which are aligned in pairs in the longitudinal direction and in the transverse direction y of the plate cover 1 1. The cover plate 1 1 also has two central reinforced support areas 45 which are aligned and regularly distributed along a central axis parallel to the longitudinal direction x of the cover plate 1 1. The cover plate cover 11 comprises ribs 26, of longitudinal orientation, and ribs 29, of transverse orientation, which connect two by two the four reinforced support zones 13 outside. In addition, the two central reinforced support zones 45 are connected to one another by a rib 46, here rectilinear, of longitudinal orientation. Finally, each of the two central reinforced support zones 45 are connected to the two adjacent external reinforced support zones 13 by ribs 47.

[01 13] In the embodiment illustrated in Figure 18, the cover plate 1 1 comprises four reinforced bearing areas 13 outside, as described in relation to Figure 17. Furthermore, the cover plate 11 comprises five central reinforced support zones 48, 56 of which four are aligned two by two parallel to the longitudinal direction x and parallel to the transverse direction y so as to define a rectangle and the fifth 48 is arranged at the intersection of the diagonals of the four other reinforced support areas 13 central. The cover plate 1 1 has ribs 29 parallel to the transverse direction y and ribs 26 parallel to the longitudinal direction x which connect two by two the four reinforced support zones 13 outside. In addition, the cover plate 1 1 has ribs 49 parallel to the transverse direction y and ribs 50 parallel to the longitudinal direction x which connect two by two the four reinforced support zones 13 central defining the rectangle. Each of the four central reinforced support zones 13 defining the rectangle is further connected by a diagonal rib 51 to the fifth central reinforced support zone 48. Finally, each of the four external reinforced support zones 13 is further connected to the central reinforced bearing zone 56 adjacent to it by a rib 52.

[01 14] In the embodiment illustrated in Figure 19, the cover plate 1 1 has four reinforced bearing areas 13 outside, as described in relation to Figure 17. The cover plate 1 1 comprises ribs 26, 29 which connect two by two the four reinforced support zones 13 outside. In addition, the cover plate 1 1 has four central reinforced support zones 53 defining a diamond whose diagonals are respectively oriented parallel to the longitudinal direction x and parallel to the transverse direction y. In addition, the cover plate 1 1 comprises ribs 54 which connect the four reinforced support zones 13 central each along one of the sides of the rhombus defined by said four central reinforced support zones 53. Finally, each of the four reinforced support zones 13 outside is connected to the central reinforced support zone 53 adjacent by a rib 55.

[01 15] The embodiment illustrated in FIG. 20 differs from the embodiment described above in relation with FIG. 19 in that the four outer reinforced bearing zones 13 are not connected to one of the zones. central reinforced supports 53. However, the two central reinforced bearing zones 53 closest to the two longitudinal ends of the cover plate 11 are each connected to the rib 29 adjacent by a connecting rib.

[01 16] Although the invention has been described in connection with several particular embodiments, it is obvious that it is in no way limited thereto and that it includes all the technical equivalents of the means described as well as their combinations. if these fall within the scope of the invention.

[0117] In particular, the different geometries of the ribs and arrangements of the reinforced support zones as described above can be combined with each other.

[01 18] It should also be noted that if the arrangements and geometries of the ribs and of the reinforced bearing zones are described above in relation to the cover plate 11, similar arrangements and geometries can also be used for the base plate 10 .

[01 19] Referring to Figure 6, a cutaway view of an LNG carrier 70 shows a sealed and insulated tank 71 of generally prismatic shape mounted in the double hull 72 of the ship. The wall of the vessel 71 comprises a primary waterproof barrier intended to be in contact with the LNG contained in the vessel, a secondary waterproof barrier arranged between the primary waterproof barrier and the double hull 72 of the ship, and two insulating barriers arranged respectively between the vessel. primary watertight barrier and the secondary watertight barrier and between the secondary watertight barrier and the double shell 72.

[0120] In a manner known per se, the loading / unloading pipes 73 arranged on the upper deck of the ship can be connected, by means of suitable connectors, to a maritime or port terminal for transferring an LNG cargo from or to the tank. 71.

[0121] FIG. 6 represents an example of a maritime terminal comprising a loading and unloading station 75, an underwater pipe 76 and an onshore installation 77. The loading and unloading station 75 is a fixed off-shore 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 hoses 79 which can be connected to the loading / unloading pipes 73. The movable arm 74 can be swiveled to fit all LNG carrier templates. A connecting pipe, 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 onshore installation 77. The latter comprises liquefied gas storage tanks 80 and connecting pipes 81 connected by the submarine pipe 76 to the loading or unloading station 75. The submarine pipe 76 allows the transfer of the liquefied gas between the loading station or unloading 75 and the installation on land 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 the loading and unloading operations.

To generate the pressure necessary for the transfer of the liquefied gas, pumps on board the ship 70 and / or pumps fitted to the shore installation 77 and / or pumps fitted to the loading and unloading station are used. 75.

[0123] The use of the verb "to include", "to understand" or "to include" and its conjugated forms does not exclude the presence of other elements or other steps than those stated in a claim.

[0124] In the claims, any reference sign between parentheses cannot be interpreted as a limitation of the claim.

Claims

[Claim 1] Insulating block (3, 7) intended for the thermal insulation of a fluid storage tank comprising:

- a first plate (11) and a second plate (10) parallel, spaced in a direction of thickness of the insulating block (3, 7);

- supporting pillars (12) interposed between said first and second plates (10, 11) in the direction of thickness of the insulating block (3, 7); and

- a heat-insulating lining (17) arranged between the supporting pillars (12);

- the first plate (11) being molded in a composite material comprising a polymer matrix reinforced by fibers and comprising reinforced bearing zones (13) against which the supporting pillars (12) bear, the reinforced bearing zones (13) being separated from each other by thinned zones (14) and having a greater thickness than that of the thinned zones (14), the reinforced bearing zones (13) being connected to each other by a network of ribs (16).

[Claim 2] An insulating block (3, 7) according to claim 1, comprising reinforced bearing zones (13) aligned in rows (r1, r2) parallel to a longitudinal direction (x) and in which the network of ribs (16) comprises ribs (26, 36, 38, 46, 50) each extending between two of the reinforced bearing zones (13) adjacent to one of the rows (r1, r2).

[Claim 3] An insulating block (3, 7) according to claim 1 or 2, comprising reinforced bearing zones (13) aligned along columns (c1, c2) parallel to a transverse direction (y) and in which the network ribs (16) comprises ribs (29, 35, 39, 49) each extending between two of the reinforced bearing zones (13) adjacent to one of the columns (c1, c2).

[Claim 4] An insulating block (3, 7) according to any one of claims 1 to 3, in which the network of ribs (16) comprises ribs (32, 41, 42, 44, 47, 51, 52) s 'each extending between two reinforced support zones (13) aligned in a direction secant to the longitudinal (x) and transverse (y) directions.

[Claim 5] An insulating block (3, 7) according to any one of claims 2 to 4, wherein each rib has a shape selected from a rectilinear shape, a curvilinear shape and an Omega shape.

[Claim 6] An insulating bioc (3, 7) according to any one of claims 2 to 5, in which the network of ribs (16) comprises connecting ribs (37, 40, 55) which each connect two ribs which s 'each extend between two reinforced support zones (13).

[Claim 7] An insulating block (3, 7) according to any one of claims 1 to 6, wherein the network of ribs (16) includes edge ribs (27, 30) each extending along a edges of the first plate (11) and in which the edge ribs (27, 30) are each connected by a rib (28, 31, 34) to one or more of the reinforced bearing zones (13).

[Claim 8] Insulating block (3, 7) according to any of the

claims 1 to 7, wherein the heat insulating liner (17) is an insulating polymeric foam which adheres to the first and second plates (10, 11).

[Claim 9] An insulating block (3, 7) according to claim 7, wherein the insulating polymeric foam further adheres to the supporting pillars (12).

[Claim 10] An insulating block (3, 7) according to claim 8 or 9, wherein the heat insulating liner (17) is obtained by molding an insulating polymer foam between the first and the second plates (10, 11).

[Claim 11] Insulating block (3, 7) according to any of the

claims 1 to 10, wherein the heat insulating liner (17) is a fiber reinforced polyurethane foam having a density of between 20 and 40 kg / m ³ and a fiber content of between 3 and 5% by mass.

[Claim 12] Insulating block (3, 7) according to any of the

Claims 1 to 11, in which at least one of the reinforced bearing zones (13) has an interlocking element (15) which cooperates by form-fitting with one end of one of the supporting pillars (12).

[Claim 13] Insulating block (3, 7) according to any of the

claims 1 to 12, wherein the supporting pillars (12) are made of a composite material comprising a polymer matrix reinforced with fibers, the supporting pillars (12) having a longitudinal direction oriented in the direction of thickness of the insulating block (3 , 7), more than 50% of the fibers of the supporting pillars (12) being oriented parallel to the direction longitudinal of the supporting pillars (12) or inclined at an angle of less than 45 ° with respect to said longitudinal direction of the supporting pillars (12).

[Claim 14] Insulating block (3, 7) according to any of the

Claims 1 to 13, in which the first plate (11) is produced by thermoforming a thermoplastic matrix reinforced with a reinforcement of fibers chosen from mats, webs and fabrics.

[Claim 15] Insulating block (3, 7) according to any of the

claims 1 to 14, the second plate (10) is molded in a composite material comprising a polymer matrix reinforced by fibers and comprising reinforced bearing zones (13) against which the bearing pillars, the bearing zones bear reinforced zones (13) being separated from each other by thinned zones (14) and having a greater thickness than that of the thinned zones (14), the reinforced bearing zones (13) being connected to each other by a network ribs (16).

[Claim 16] Insulating block (3, 7) according to any of the

claims 1 to 15, wherein the supporting pillars (12) are produced by pultrusion.

[Claim 17] Insulating block (3, 7) according to any of

claims 1 to 16, in which the supporting pillars (12) are hollow and lined with a heat insulating lining (24).

[Claim 18] Insulating block (3, 7) according to any of the

claims 1 to 17, wherein the first plate (11) is a cover plate (11).

[Claim 19] Tight and thermally insulating fluid storage tank comprising a thermal insulation barrier (2, 6) comprising a plurality of insulating blocks (3, 7) according to any one of

claims 1-18 juxtaposed, and a waterproofing membrane (5, 9) resting against the thermal insulation barrier (2, 6).

[Claim 20] A vessel (70) for transporting a fluid, the vessel

comprising a double shell (72) and a tank (71) according to claim 19 disposed in the double shell.

[Claim 21] A transfer system for a fluid, the system comprising a vessel (70) according to claim 20, insulated pipes (73, 79, 76, 81) arranged to connect to the vessel (71) installed in the hull from the ship to a floating or onshore storage facility (77) and a pump for driving fluid through insulated pipelines from or to the floating or onshore storage facility to or from the vessel's vessel.

[Claim 22] A method of loading or unloading a vessel (70) according to claim 20, wherein a fluid is conveyed through insulated pipelines (73, 79, 76, 81) from or to a floating storage facility or land (77) to or from the vessel's tank (71).