WO2014096600A1

WO2014096600A1 - Sealed, thermally insulating vessel

Info

Publication number: WO2014096600A1
Application number: PCT/FR2013/052917
Authority: WO
Inventors: Nicolas THENARD; Guillaume Leclere; Gery Canler
Original assignee: Gaztransport Et Technigaz
Priority date: 2012-12-21
Filing date: 2013-12-03
Publication date: 2014-06-26
Also published as: CN104870882A; KR20150096681A; AU2013366322B2; CN104870882B; FR3000042A1; AU2013366322A1; FR3000042B1; KR101994435B1

Abstract

The invention relates to the secondary insulating barrier of a sealed, thermally insulating vessel which comprises a set of heat-insulating, generally parallelepiped-shaped elements (6) added to the bearing structure such as to form a substantially uniform supporting surface for the secondary sealing membrane, and retaining members attached to the bearing surface between the added heat-insulating elements and engaging with the heat-insulating elements such as to retain the heat-insulating elements against the bearing structure. An heat-insulating element of the secondary insulating barrier comprises a first parallelepiped sub-assembly (11, 13, 14) extending parallel to the secondary sealed membrane, and a second parallelepiped sub-assembly (16, 18) that has a shorter length such as to leave an upper surface (21) uncovered. A retaining member comprises an attachment element having peripheral portions engaging with the uncovered portion of the upper surface (21) of the intermediate panels of the heat-insulating elements (6) between which the retaining member is placed such as to retain the heat-insulating elements against the bearing surface.

Description

SEALED AND THERMALLY INSULATED TANK

The invention relates to the field of sealed and thermally insulating tanks arranged in a bearing structure for containing a cold fluid, in particular to membrane tanks for containing liquefied gases.

Waterproof and thermally insulating vessels can be used in different industries to store hot or cold products. For example, in the energy field, liquefied natural gas (LNG) is a liquid with a high methane content that can be stored at atmospheric pressure at about -163 ° C in land-based storage tanks or in on-board tanks. in floating structures.

Such a tank is disclosed for example in FR-A-2867831. In this known tank, a primary insulating barrier and a secondary insulating barrier are formed in a modular form using juxtaposed wooden parallelepiped boxes. The crates are filled with an expanded perlite insulation or aerogels.

FR-A-2798902 discloses another LNG tank arranged in the hull of a ship in which a primary insulating barrier and a secondary insulating barrier each consist of a single layer of caissons filled with low density foam blocks, order of 33 to 40 kg / m3 glued to wooden plywood spacers.

According to one embodiment, the invention provides a sealed and thermally insulating tank arranged in a supporting structure for containing a cold fluid,

wherein a wall of the vessel comprises successively a primary waterproof membrane intended to be in contact with the fluid, a primary insulating barrier, a secondary sealed membrane parallel to the primary waterproof membrane and a secondary insulating barrier disposed between the secondary waterproof membrane and the supporting structure, wherein the secondary insulating barrier comprises a plurality of parallelepiped-shaped heat insulating elements juxtaposed on the carrier structure to form a substantially uniform support surface for the secondary waterproof membrane, and

retaining members attached to the supporting structure between the heat-insulating elements juxtaposed and cooperating with the heat-insulating elements to retain the heat-insulating elements against the supporting structure,

wherein a heat insulating element of the secondary insulating barrier comprises: a first parallelepipedal subassembly extending parallel to the secondary watertight membrane, the first parallelepipedic subassembly comprising a first block of high density polymer foam, a bonded bottom panel under the first block of high density polymer foam, an intermediate panel adhered to the first block of high density polymer foam, and a plurality of small section stiffening pillars disposed between the bottom panel and the intermediate panel and extending into the direction of the thickness of the first block of high density polymer foam, and

a second parallelepipedal subassembly extending parallel to the secondary waterproof membrane, the second parallelepipedal subassembly comprising a second block of polymer foam bonded to the intermediate panel and a cover panel bonded to the second block of polymer foam, the second parallelepipedic subassembly having a length less than the length of the first parallelepipedal subassembly and being substantially centered on the first parallelepipedal subassembly so as to reveal an upper surface of the intermediate panel at two opposite end portions of the first parallelepipedic sub-assembly; and wherein a retaining member comprises:

a rod oriented according to the thickness of the secondary insulating barrier and having a lower end portion attached to the supporting structure, and

a fastener connected to an upper end portion of the rod, the fastener having a lower surface and an upper surface parallel to the secondary waterproof membrane and separated by a distance equal to the thickness of the second parallelepipedic sub-assembly,

the lower surface of the fastening element having peripheral portions cooperating with the uncovered portion of the upper surface of the intermediate panels of the heat-insulating elements between which the retaining member is arranged to retain the heat-insulating elements against the supporting structure, the upper surface of the flush fastening element at the top surface of the cover panels of the heat insulating elements between which the retaining member is arranged to form with said cover panels the substantially uniform support surface for the secondary waterproof membrane.

According to embodiments, such a tank may comprise one or more of the following provisions.

The stiffening pillars may be provided in greater or lesser number and arranged in different ways in the first parallelepiped sub-assembly. According to one embodiment, the stiffening pillars of the first parallelepipedal subassembly are disposed between the bottom panel and the intermediate panel at the two opposite end portions of the first parallelepipedal subassembly. Such an arrangement makes it possible to effectively take back any compression forces transmitted via the fastening element onto the uncovered portion of the intermediate panel.

According to one embodiment, the first parallelepipedal subassembly comprises four stiffening pillars arranged at the four corners of the first block of foam. Such an arrangement makes it possible to create in a simple manner a relatively rigid frame for stabilizing the foam block, in particular to counter bending stresses generated by the differential thermal expansion. Preferably, the ends of the stiffening pillars are attached, for example stapled, nailed and / or glued, to the bottom panel and the intermediate panel.

According to one embodiment, the first parallelepipedal subassembly has a recess extending over the entire thickness of the first sub-assembly. parallelepipedal assembly at each of the four corners of the first parallelepiped subassembly to form clearances in which the retaining members are disposed, the recess having a depth equal to the depth of the exposed end portion of the intermediate panel, so that a side wall of the first parallelepiped subassembly at the bottom of the recess is aligned with a side wall of the second parallelepiped subassembly.

According to one embodiment, the recess has a rectangular section and the stiffening pillar disposed at the corner of the first foam block has two perpendicular flanges along two sides of the recess. Such an arrangement allows in particular to protect the corner of the foam block against accidental damage during the introduction of the retainers.

According to one embodiment, the fixing element comprises a lower metal plate forming the lower surface, an upper metal plate forming the upper surface and a block of rigid insulating material arranged between the lower and upper metal plates. Such an arrangement makes it possible to produce a relatively wide fixing element for distributing the forces transmitted to the intermediate panel in engagement with the lower surface. Such an arrangement also makes it possible to produce a relatively solid fastening element to take up any compression forces in the event of damage to an adjacent secondary heat-insulating element while limiting the thermal bridge formed towards the supporting structure.

The panels can be made of different materials, for example in a composite material resistant to bending and shearing. According to one embodiment, the bottom panel, the intermediate panel and the cover panel are made of plywood. Such a material is economical and offers varied supply possibilities.

According to one embodiment, the high-density polymer foam has a density greater than 90 kg / m 3, for example between 120 and 140 kg / m 3. In particular, the high density polymer foam can be selected from the group consisting of polyurethane foam and polyurethane foam reinforced with glass fibers.

According to one embodiment, cords of putty disposed on a lower surface of the bottom panel bear against the supporting structure so as to compensate for flatness defects of the carrier structure.

According to one embodiment, the primary insulating barrier consists of juxtaposed heat insulating elements, a heat insulating element of the primary insulating barrier comprising in each case a box filled with an insulating packing consisting essentially of mineral wool or perlite.

According to one embodiment, the or each sealed membrane comprises parallel metal sheet strips whose longitudinal edges are raised projecting inwardly of the tank and parallel welding wings retained on the underlying thermal insulation barrier and projecting inwardly from the vessel each between two strips of sheet metal to form a sealed welded joint with the adjacent raised longitudinal edges.

Such a tank can be part of a land storage facility, for example to store LNG or be installed in a floating structure, coastal or deep water, including a LNG tank, a floating storage and regasification unit (FSRU) , a floating production and remote storage unit (FPSO) and others.

According to one embodiment, a vessel for the transport of a cold liquid product comprises a double hull and a aforementioned tank disposed in the double hull.

According to one embodiment, the invention also provides a method of loading or unloading such a vessel, in which a cold liquid product is conveyed through isolated pipes from or to a floating or land storage facility to or from the vessel vessel.

According to one embodiment, the invention also provides a transfer system for a cold liquid product, the system comprising the abovementioned vessel, insulated pipes arranged to connect the vessel installed in the hull of the vessel. vessel at a floating or land storage facility and a pump for driving a flow of cold liquid product through the insulated pipelines from or to the floating or land storage facility to or from the vessel vessel. An idea underlying the invention is to design a tank wall structure, and in particular a secondary insulating barrier structure, offering advantageous properties as regards the thermal insulation, the mechanical strength and the cost price.

Some aspects of the invention derive from the observation that when a sealed and thermally insulated tank is filled with liquefied natural gas, the difference in temperature between the outside of the tank and the inside of the tank generates a thermal gradient within the heat insulating elements. This thermal gradient can cause differential expansion phenomena within bonded assemblies of polymer foam with other rigid materials, for example plywood, likely to cause stresses tending to bend the heat insulating elements. This bending may in particular occur when the fastening means of the heat-insulating element in the tank are not able to fully recover these stresses, for example when the heat-insulating element is not glued to the shell over its entire surface area, but only attached at a plurality of attachment points.

Certain aspects of the invention start from the idea of producing relatively thick heat insulating elements for a secondary insulating barrier while placing an intermediate panel within the thickness of the heat-insulating element in order to limit thermal bending stresses. .

The invention will be better understood, and other objects, details, characteristics and advantages thereof will appear more clearly in the course of the following description of several particular embodiments of the invention, given solely for illustrative and non-limiting purposes. with reference to the accompanying drawings.

On these drawings:

• Figure 1 is a partial cutaway perspective view of a sealed and insulating tank wall. FIG. 2 is a perspective view of a secondary heat insulating element of the wall of FIG. 1.

• Figure 3 is a plan view of the secondary heat insulating element of Figure 2 according to the arrow III.

FIG. 4 is an enlarged sectional view of a corner pillar of the secondary heat insulating element along line IV of FIG. 3.

FIG. 5 is a plan view of a coupler that can be used in the vessel wall of FIG.

• Figure 6 is a schematic cutaway representation of a tank LNG tank and a loading / unloading terminal of the tank.

• Figures 7 and 8 are two diagrams of principles illustrating a differential contraction phenomenon generating a bending moment.

We will briefly recall the phenomenon of differential contraction with two simple examples illustrated schematically in Figures 7 and 8.

A plywood panel 37 is adhered to a thicker one-piece polymer foam layer 36. The plywood panel 37 and the polymeric foam layer 36 are subjected to a thermal gradient 38 downward. This means that the temperature at the plywood panel 37 is lower than the temperature at the lower surface 41 of the polymeric foam layer 36. The polymeric foam has a greater coefficient of thermal expansion than the plywood. Thus, the polymeric foam shrinks more with respect to the ambient temperature than the plywood panel 37 under the effect of the thermal gradient 38. As the plywood panel 37 and the polymeric foam layer 36 are glued together and that in addition the Polymeric foam 36 is stiffer in bending than plywood 37, panel 37 and polymeric foam layer 36 tend to flex along convex curvature 39.

The same phenomenon can be observed in a second example schematically illustrated in FIG. 8, where the plywood panel 37 is glued. below that of the polymeric foam layer 36. However, in this case, the polymeric foam layer 36 and the panel 37 tend to flex at a convex curvature opposite to the convex curvature 39 described in the first example. Furthermore, since the plywood panel 37 is located below the polymeric foam layer 36, this panel 37 is subjected to a temperature that is hotter than in the first example for the same thermal gradient 38. Accordingly, this contract less than in the first example, which generates a convex curvature 40 greater than the convex curvature 39 of the first example. This is because the difference in thermal contraction between the polymeric foam layer 36 and the panel 37 is greater than in the first example.

Figure 1 shows a sealed and thermally insulating wall in perspective cut away to show the structure of this wall. Such a structure can be implemented on large surfaces having various orientations, for example to cover bottom, ceiling and side walls of a tank. The orientation of Figure 1 is not limiting in this regard.

The tank wall is attached to the wall of a load-bearing structure 1. By convention, the term "above" a position located closer to the inside of the tank and "below" a position located closer to the structure carrier 1, regardless of the orientation of the vessel wall relative to the earth's gravity field.

The vessel wall comprises a secondary insulating barrier 2, a secondary sealed barrier 3 retained on the top of the secondary insulating barrier 2, a primary insulating barrier 4 retained on the secondary watertight barrier 3 and a primary sealed barrier 5 retained on top of the secondary insulating barrier 3 the primary insulating barrier 4.

The secondary insulating barrier 2 consists of a plurality of parallelepipedal secondary insulating modules 6 which are arranged side by side, so as to substantially cover the inner surface of the supporting structure 1. To allow the flatness of the sealed membranes, cords of mastic 7 are installed between the supporting structure 1 and the lower surface of the insulating modules 6. These cords mastic are for example glued on the lower surface of the secondary insulation module 6. They do not adhere to the supporting structure

1 due to the establishment of a kraft paper not shown between the carrier structure 1 and the sealant. According to one embodiment, the cords of mastic may be corrugated cords as described in FR-A1-2931535. Shims 28 are also provided on the bearing wall to support the corners of the secondary insulating modules 6.

A secondary insulating module 6 is shown in more detail in the figures

2 and 3. It consists of two parts: a parallelepipedal subassembly 10 in the lower part close to the carrier structure 1 and a parallelepiped subassembly 20 slightly shorter in the upper part.

The subassembly 10 comprises a block of high-density polymer foam 11, in particular polyurethane with or without glass fibers, sandwiched between two flat plywood boards 13 and 14. The foam block 11 has an overall shape of Rectangular parallelepiped with cutouts in the corners to let corner pillars 12.

The bottom panel 13 and the intermediate panel 14 have an identical shape, namely a rectangle shape with a rectangular recess 15 in each corner to create clearances in the tank wall in the assembled state, at the interface between several secondary insulation modules 6 juxtaposed. These clearances serve to receive mechanical couplers 30, visible in FIG.

Thus, the cutting of the subassembly 10 is optimized so as to limit as far as possible the thermal chimneys present between the foam blocks. Preferably, the only games present are the mounting sets and the passages of the mechanical couplers 30 in the corners.

The foam block 11 is adhered to its entire surface at the bottom panel 13 and at the intermediate panel 14. At each corner, the foam block 11 is glued over its entire height to the corner pillar 12. The pillar angle 12 is furthermore attached to the bottom panel 13 and the intermediate panel 14 by staples or the like.

Figure 4 shows the section of the corner pillar 12 in one embodiment. The internal surfaces 17 are bonded to the side wall of the foam block 11 while the outer surfaces 15 are in continuity with the rectangular recess 15 of the bottom panel 13 and the intermediate panel 14. The corner pillars 12 allow take back part of the compressive load in service and thus limit the crushing and the creep of the foam 11.

The parallelepipedic subassembly 20 located in the upper part of the secondary insulating module 6 comprises a second block of high density polymer foam 16, in particular polyurethane with or without glass fibers, sandwiched between the intermediate panel 14 and a panel of cover 18 in plywood. Foam block 16 is glued over its entire surface to the cover panel 18 and the intermediate panel 14 and has no pillar, which simplifies its manufacture and assembly. The foam block 16 is substantially less thick than the foam block 11, for example about 1/3 of the thickness of the foam block 11. As the parallelepipedal subassembly 20 is shorter than the subassembly 10, the two longitudinal ends of the intermediate panel 14 are unobstructed and provide a free upper surface 21 strip-shaped.

In order to facilitate the construction of the vessel wall, the secondary insulating module 6 is preferably provided in the form of a prefabricated element. In one embodiment, the following dimensions are provided:

Length of the subassembly 10: 118 cm

Length of the subassembly 20: 114 cm

Width of secondary insulation module 6: 100 cm

Thickness of the foam block 11: 20 cm

Thickness of the foam block 16: 6.5 cm

Thickness of the cover panel 18: 1,5 cm Thickness of the bottom panel 13: 1 cm

Thickness of the intermediate panel 14: 1 cm

Thickness of the secondary insulation module 6: 30 cm

These thicknesses of the insulation barriers are advantageous in that they respect the dimensions of prior designs and are therefore compatible with elements available on the market, such as anchoring systems, sealing membranes and the different zones. singular that are the dihedra and trihedrons of the vats.

Returning to FIG. 1, it can be seen that the mechanical couplers 30 are positioned at the corners of the secondary insulating modules 6 at the rate of four mechanical couplers 30 per module 6. The free surface 21 of the intermediate panel 14 makes it possible to engage the mechanical couplers 30 for retaining the secondary insulating modules 6 on the carrier wall 1.

A mechanical coupler 30 is shown in greater detail in FIG. 5. The mechanical coupler 30 comprises a bushing 22 whose base is welded to the carrier structure 1 in a position corresponding to a clearance at the corners of four secondary insulating modules 6 adjacent. The bushing 22 carries a first rod 23 screwed to it. The rod 23 passes between the adjacent modules 6. A fastener is mounted on the rod 23 to clamp the modules 6 against the supporting structure 1 at the free surfaces 21 of the intermediate panel 14. The fastener comprises a lower metal plate 24, an upper plate 26 and a block plywood 25 mounted on the plate 24 so as to serve as a spacer between the plate 24 and the upper plate 26 and reduce the thermal bridge to the supporting structure 1. The height of this arrangement is determined so that the platinum upper 26 comes flush at the cover panels 18 to support the secondary membrane 3. In other words, the thickness 29 of the fastener formed by the block 25 and the plates 24 and 26 is equal to the thickness of the subassembly 20. In addition, the thickness of the subassembly 10 corresponds to the distance 50 between the spacer 28 and the bottom plate 24. The block of wood 25 has a housing 47 in which the upper end of the rod 23 is engaged through a central bore of the lower plate 24. The lower plate 24 is retained on the rod 23 by means of a nut 48 with interposing a plurality of Belleville washers 49 to provide an elastic play.

At the corners of the subassembly 10, the compression force applied by the mechanical coupler 30 to the insulating module 6 is taken up by the corner pillars 12.

The cover panels 18 of the insulating modules 6 furthermore comprise a pair of parallel grooves 19 in a substantially inverted T-shape for receiving square-shaped welding wings. The portion of the welding flanges projecting towards the top of the panels 18 allows anchoring of the secondary sealing barrier 3. The secondary sealing barrier consists of a plurality of Invar® strakes with raised edges, having a thickness of the order of 0.7 mm. The raised edges of each strake are welded to the aforementioned welding wings according to the known technique.

On the secondary sealing barrier is mounted the primary insulating barrier 4 which consists of a plurality of primary insulating boxes 33. Each primary insulating box 33 consists of a rectangular parallelepiped box made of plywood, which is filled non-structural insulating material such as perlite or glass wool. The primary insulating boxes 33 also comprise internal partitions, a bottom panel and a top panel 45. The top panel 45 also has two grooves 46 in the general shape of inverted T, to also receive a welding flange on which are welded the raised edges of the strakes of the primary sealing barrier. The gap between two grooves 19 or 46 corresponds to the width of a strake. The gap between the grooves and the adjacent edge of the same box corresponds to the half-width of a strake, so that a strake comes to overlap two adjacent boxes. In case of rupture of the primary membrane 5, the primary insulating barrier 4 is flooded with LNG so that the secondary membrane 3 is at the very cold temperature of the liquid. The secondary insulating module 6 is then subjected to a very important thermal gradient. The intermediate plate 14 is arranged in the zone of thickness where this gradient is very important, and then performs the function of reducing the bending forces generated by the differential contraction of the materials, namely foam and plywood. In addition, the hydrostatic pressure force supported by the secondary membrane 3 is transmitted by the coupler 30 on the surface 21 of the intermediate panel 14 and can be taken directly by the pillars 12. Thus the risk of flowing the block of foam 11 is reduced.

The techniques described above for making a sealed and insulated wall can be used in different types of tanks, for example to form the wall of an LNG tank in a land installation or in a floating structure such as a LNG tank or other.

Referring to Figure 6, a cutaway view of a LNG tank 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 tank 71 comprises a primary sealed barrier intended to be in contact with the LNG contained in the tank, a secondary sealed barrier arranged between the primary waterproof barrier and the double hull 72 of the ship, and two insulating barriers arranged respectively between the primary watertight barrier and the secondary watertight barrier and between the secondary watertight barrier and the double hull 72.

In a manner known per se, loading / unloading lines 73 arranged on the upper deck of the ship can be connected, by means of appropriate connectors, to a marine or port terminal to transfer a cargo of LNG from or to the tank 71.

FIG. 6 shows an example of a marine 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 off-shore fixed 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 that can be connected to the loading / unloading pipes 73. The movable arm 74 is adjustable. suitable for all models of LNG carriers. A connection pipe (not shown) extends inside the tower 78. The loading and unloading station 75 enables the loading and unloading of the LNG tank 70 from or to the shore facility 77. liquefied gas storage tanks 80 and connecting lines 81 connected by the underwater line 76 to the loading or unloading station 75. The underwater line 76 allows the transfer of the liquefied gas between the loading or unloading station 75 and the onshore installation 77 over a large distance, for example 5 km, which makes it possible to keep the tanker vessel 70 at great distance from the coast during the loading and unloading operations.

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

Although the invention has been described in connection with several particular embodiments, it is obvious that it is not limited thereto and that it comprises all the technical equivalents of the means described and their combinations if they are within the scope of the invention.

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 steps other than those set out in a claim. The use of the indefinite article "a" or "an" for an element or a step does not exclude, unless otherwise stated, the presence of a plurality of such elements or steps.

In the claims, any reference sign in parentheses can not be interpreted as a limitation of the claim.

Claims

1. Watertight and thermally insulating vessel arranged in a supporting structure for containing a cold fluid,

wherein a wall of the vessel comprises successively a primary waterproof membrane (5) intended to be in contact with the fluid, a primary insulating barrier (4), a secondary waterproof membrane (3) parallel to the primary waterproof membrane and an insulating barrier secondary (2) disposed between the secondary waterproof membrane and the supporting structure,

wherein the secondary insulating barrier comprises a plurality of generally parallelepiped-shaped heat insulating elements (6) juxtaposed to the carrier structure to form a substantially uniform support surface for the secondary waterproof membrane, and

retaining members (30) attached to the supporting structure between the heat-insulating elements juxtaposed and cooperating with the heat-insulating elements to retain the heat-insulating elements against the supporting structure,

in which a heat insulating element of the secondary insulating barrier comprises: a first parallelepiped subassembly (10) extending parallel to the secondary waterproof membrane, the first parallelepipedal subassembly comprising a first block of high density polymer foam (11) , a bottom panel (13) adhered under the first block of high density polymer foam, an intermediate panel (14) adhered to the first block of high density polymer foam, and a plurality of small section stiffening pillars (12) disposed between the bottom panel and the intermediate panel and extending in the thickness direction of the first block of high density polymer foam, and

a second parallelepipedic subassembly (20) extending parallel to the secondary waterproof membrane, the second parallelepipedal subassembly comprising a second polymeric foam block (16) adhered to the intermediate panel and a cover panel (18) adhered to the second block of polymeric foam, the second parallelepipedal subassembly having a length less than the length of the first parallelepipedal subassembly and being substantially centered on the first parallelepipedal subassembly so as to reveal an upper surface (21) of the intermediate panel at two opposite end portions of the first parallelepipedic subassembly ,

and wherein a retaining member comprises:

a rod (23) oriented according to the thickness of the secondary insulating barrier and having a lower end portion attached to the supporting structure, and a fastening element connected to an upper end portion of the rod, the element of fastener having a lower surface (24) and an upper surface (26) parallel to the secondary waterproof membrane and separated by a distance (29) equal to the thickness of the second parallelepipedic subassembly (20),

the lower surface of the fastening element having peripheral portions cooperating with the uncovered portion of the upper surface (21) of the intermediate panels of the heat-insulating elements (6) between which the retaining member is arranged to retain the heat-insulating elements against the carrier structure, the upper surface (26) of the fastener flush with the top surface of the cover panels (18) of the heat-insulating elements between which the retaining member is arranged to form with said cover panels the surface substantially uniform support for the secondary waterproof membrane (3).

2. Tank according to claim 1, wherein the stiffening pillars (12) of the first parallelepiped subassembly are arranged between the bottom panel and the intermediate panel (14) at the two opposite end portions of the first subassembly. cuboid.

3. Tank according to claim 2, wherein the first parallelepiped subassembly comprises four stiffening pillars arranged at the four corners of the first block of foam (11).

4. A tank according to claim 3, wherein the first parallelepipedic subassembly has a recess (15) extending over any the thickness of the first parallelepiped subassembly at each of the four corners of the first parallelepiped subassembly to form clearances in which the retaining members (30) are arranged, the recess having a width equal to the width of the exposed end portion of the intermediate panel, so that a side wall of the first parallelepiped subassembly at the bottom of the recess is aligned with a side wall of the second parallelepiped subassembly.

5. Tank according to claim 4, wherein the recess has a rectangular section and the stiffening pillar disposed at the corner of the first block of foam has two perpendicular wings (15) along two sides of the recess.

6. Tank according to one of claims 1 to 5, wherein the fastener element comprises a lower metal plate (24) forming the lower surface, an upper metal plate (26) forming the upper surface and a block of insulating material. rigid (25) arranged between the lower and upper metal plates.

7. Tank according to one of claims 1 to 6, wherein the bottom panel, the intermediate panel and the lid panel are plywood.

8. Tank according to one of claims 1 to 7, wherein the high density polymer foam has a density greater than 90kg / m3.

The vessel of one of claims 1 to 8, wherein the high density polymer foam is selected from the group consisting of polyurethane foam and glass fiber reinforced polyurethane foam.

10. Tank according to one of claims 1 to 9, wherein cords of sealant (7) disposed on a lower surface of the bottom panel (13) bear against the supporting structure so as to compensate for unevenness of the surface. the supporting structure.

11. Tank according to one of claims 1 to 10, wherein the primary insulating barrier consists of juxtaposed heat insulating elements (33), a heat insulating element of the primary insulating barrier comprising in each case a box filled with an insulating packing consisting essentially of mineral wool or perlite.

12. Tank according to one of claims 1 to 11, wherein each waterproof membrane (3, 5) comprises parallel metal sheet strips whose longitudinal edges are raised projecting towards the inside of the tank and welding wings parallel lines retained on the underlying thermal insulation barrier and projecting inwardly of the vessel each between two strips of sheet metal to form a sealed welded joint with the adjacent raised longitudinal edges.

13. Ship (70) for the transport of a cold liquid product, the vessel having a double hull (72) and a tank (71) according to one of claims 1 to 12 disposed in the double hull.

The method of using a ship (70) according to claim 13, wherein a cold liquid product is conveyed through isolated ducts (73, 79, 76, 81) to or from a floating or land storage facility. (77) to or from the vessel vessel (71) for loading or unloading the vessel.

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