EP2959207B1 - Method for producing a sealed and thermally insulating barrier for a storage tank - Google Patents

Description

The invention relates to the field of sealed and thermally insulated tanks, membrane, for the storage and / or transport of fluid, such as a cryogenic fluid. The invention relates more particularly to the manufacture of a sealed membrane tank in which the thermal insulation is partly achieved by projection, in situ, of insulating foam.

Watertight and thermally insulated membrane tanks are used in particular for the storage of liquefied natural gas (LNG). These tanks can be installed on the ground 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 used as fuel for the propulsion of the floating structure.

In the state of the art, it is known to manufacture such tanks from prefabricated insulation panels. Such insulating panels have an insulating foam layer, optionally reinforced with glass fibers, sandwiched between two plywood plates. The manufacture of a thermal insulation barrier from such prefabricated panels is long and costly since it requires transporting the prefabricated panels and then putting them one by one.

It is, moreover, known from the state of the art to manufacture insulating barriers, in situ, against a supporting structure.

The document US 3,759,209 discloses the manufacture of an insulation barrier, exterior to the hull of a vessel carrying liquefied natural gas. This document provides for fixing a formwork template, consisting of horizontal and vertical beams defining a plurality of compartments, on the outer shell of the vessel and then placing insulating foam in the compartments. The formwork jig is held in place and a waterproofing membrane is attached thereto. However, the formwork template does not compensate for the thermal contraction of the foam so that the continuity of the thermal insulation between the different foam compartments is not ensured when the wall is subjected to cryogenic temperatures.

The document FR 2 191 064 also discloses a method of manufacturing a tank for transporting liquefied natural gas. This document provides for spacers on a supporting structure and then forming a network of fiberglass or wire cables, which are tensioned and supported by the spacers. A plywood plate is then attached to the head of the spacers and an expandable urethane solution is then injected into the space between the plywood plate and the supporting structure.

The document DE19934620 discloses a sealed and thermally insulating wall for a cryogenic fluid storage tank, comprising a supporting structure, a plurality of anchoring elements attached to the supporting structure, a plurality of insulating foam insulating sectors and strips of thermally insulating materials 150, for example glass wool, which are interposed in the junction areas between insulation insulating foam sectors.

The thermal insulation layer is part of a prefabricated panel and is carried by a plate 3 of plywood 9 mm thick. The plywood plate 3 rests against the supporting structure 1 by means of polymerizable resin rods 13. Furthermore, the panels 2 are fixed against the bearing structure by means of studs.

An idea underlying the invention is to provide a method of manufacturing, in situ, an insulating barrier cryogenic liquid storage tank, by foam projection which, on the one hand, allows for a wall providing a continuity of the thermal insulation and which, on the other hand, is easy to implement.

According to a first aspect, the invention relates to a method of manufacturing a wall, sealed and thermally insulating, for fluid storage tank as defined in one of claims 1 to 3.

Thus, this wall manufacturing method benefits from the advantages associated with the use of a formwork jig since it is simple to implement and makes it possible to break up the thermal insulation layer so as to limit the mechanical stresses associated with temperature differences between its external and internal surfaces while ensuring continuity of thermal insulation when the wall is subjected to low temperatures. Advantageously, it is put in place on the carrier structure combined elements, a combined element comprising a modular formwork element and a junction insulating element housed, under stress, inside the modular formwork element and the junction insulating element is left, in a stressed position, between said insulating sectors during removal of the modular formwork elements. Thus, the removal of the modular elements and the arrangement of the insulating junction elements in the stressed position are performed simultaneously.

In another embodiment, combined elements are provided on the carrier structure, a combined element comprising a modular formwork element and an insulation junction element, the modular formwork element comprising two lost formwork flanks between which a junction insulating element is housed under stress and releasable means for clamping the flanks, the junction insulating element, housed under stress between the two sides of lost formwork, is arranged in its constrained position after release of the clamping means of the flanks, the insulating member in its stressed position engaging the two lost formwork flanks with the insulating sectors between which the combined element is located.

• Les éléments isolants de jonction sont compressibles.
• les compartiments sont mutuellement adjacents et deux compartiments mutuellement adjacents étant à chaque fois séparé par un élément modulaire de coffrage disposé entre eux.
• un élément modulaire de coffrage présente un revêtement antiadhésif.
• un élément isolant de jonction comporte un profilé présentant deux lèvres élastiques qui, en position contrainte entre les secteurs isolants, sont contraintes vers leur rapprochement et exercent une force de réaction tendant à les écarter l'une de l'autre.
• le profilé présentant deux lèvres élastiques est réalisé dans une mousse d'un polymère choisi parmi le polyuréthane, la mélamine, le polyéthylène, le polypropylène, le polystyrène ou le silicone.
• un élément isolant de jonction comporte une bande formée dans un matériau compressible choisi parmi la laine de verre, l'ouate de polyester, les mousses de polyuréthane, mélamine, polyéthylène, polypropylène ou silicone.
• le procédé comporte une étape d'arasage des secteurs isolants.
• un élément d'ancrage est un plot, équipé d'un organe d'ancrage à la structure porteuse et d'un élément de fixation de la membrane d'étanchéité et comportant au moins une couche thermiquement isolante.
• la couche thermiquement isolante du plot est réalisée en mousse polymère présentant une densité supérieure à 100 kg/m³ ou en bois.
• le procédé comporte une étape de fixation de plats d'ancrage entre les plots d'ancrage adjacents et une étape de soudage de la membrane d'étanchéité sur lesdits plats d'ancrage.
• lors de la mise en place d'éléments modulaires de coffrage sur la structure porteuse, l'on fixe les éléments modulaires de coffrage à la structure porteuse et/ou aux éléments d'ancrage.

According to other advantageous embodiments:

• Insulating junction elements are compressible.
• the compartments are mutually adjacent and two mutually adjacent compartments each separated by a modular formwork element arranged between them.
• a modular formwork element has a non-stick coating.
• an insulating junction element comprises a profile having two resilient lips which, in the constrained position between the insulating sectors, are forced towards them and exert a reaction force tending to separate them from each other.
• the profile having two elastic lips is made of a foam of a polymer selected from polyurethane, melamine, polyethylene, polypropylene, polystyrene or silicone.
• an insulating junction element comprises a band formed in a compressible material selected from glass wool, polyester wadding, polyurethane foams, melamine, polyethylene, polypropylene or silicone.
• the method comprises a step of shaving the insulating sectors.
• an anchoring element is a stud, equipped with an anchoring member to the supporting structure and a fastening element of the sealing membrane and comprising at least one thermally insulating layer.
• the thermally insulating layer of the pad is made of polymer foam having a density greater than 100 kg / m ³ or wood.
• the method comprises a step of fixing anchoring plates between the adjacent anchoring studs and a step of welding the waterproofing membrane on said anchoring plates.
• when modular formwork elements are placed on the supporting structure, the modular formwork elements are fixed to the supporting structure and / or to the anchoring elements.

According to a second aspect, the invention also provides a wall, sealed and thermally insulating, for cryogenic fluid storage tank, as defined by one of claims 13 or 14.

Advantageously, the insulating sectors adhere against the carrier structure. Thus, thanks to the adhesion capacity of the projected foam, the insulating sectors are held in place relative to the carrier structure, which simplifies the implementation of the method. This feature also makes it possible to prevent the insulating sectors from exerting a bearing pressure on the membrane when the wall is a vertical wall or a ceiling.

According to a third aspect, the invention relates to a cryogenic liquid storage tank having at least one wall according to the second aspect of the invention.

According to one embodiment, a vessel for transporting a cold liquid product comprises a storage tank mentioned above.

In one embodiment, the vessel comprises a single or double hull and a aforementioned tank disposed in the single or double hull.

In another embodiment, the vessel has a bridge and the aforesaid vessel is disposed on the deck. In this case, the bearing structure of the vessel may consist of a sheet metal structure disposed on the deck of the vessel. Such tanks have, for example, a volume of between 5000 and 30,000 m ³ and can be used for fueling machinery.

The tank can be used to store liquefied natural gas at atmospheric pressure or under a relative overpressure in accordance with the compressive strength of the foam used, for example 3 bar for a foam having a compressive strength of 0.3 MPa.

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 to a floating storage facility. or terrestrial 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.

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.

• La figure 1 est une vue en perspective d'éléments modulaires de coffrage définissant avec une pluralité de plots d'ancrage et une structure porteuse des compartiments destinés à recevoir de la mousse projetée.
• La figure 2 est une vue en perspective, similaire à celle de la figure 1, dans laquelle de la mousse a été projetée dans les compartiments.
• La figure 3 est une vue en perspective, similaire à celle de la figure 2, dans laquelle les éléments modulaires de coffrage ont été retirés.
• La figure 4 est une vue en perspective, similaire à celle de la figure 3, dans laquelle des éléments isolants de jonction ont été disposés entre les secteurs en mousse projetée.
• La figure 5 est une vue de dessus représentant des secteurs en mousse projetée, des plots d'ancrage et des éléments isolants de jonction disposés entre lesdits secteurs en mousse projetée.
• La figure 6 est une vue en perspective d'un plot d'ancrage selon un premier mode de réalisation.
• La figure 7 est une vue en perspective d'un plot d'ancrage selon un second mode de réalisation, adapté pour la fabrication d'une paroi présentant successivement deux niveaux, primaire et secondaire, d'étanchéité et d'isolation thermique.
• La figure 8 est une vue de dessus représentant des plots d'ancrage et des plats d'ancrage permettant la fixation d'une membrane d'étanchéité.
• La figure 9 est une vue de côté d'un plot d'ancrage supportant des plats d'ancrage.
• La figure 10 est une vue de côté d'un plot d'ancrage selon un troisième mode de réalisation.
• La figure 11 est une vue de côté d'un plot d'ancrage selon un quatrième mode de réalisation.
• La figure 12 est une illustration détaillée du plot d'ancrage de la figure 11.
• La figure 13 est une vue schématique en coupe d'un élément isolant de jonction selon un mode de réalisation.
• La figure 14 est une vue schématique en coupe d'un élément isolant de jonction selon un autre mode de réalisation.
• La figure 15 est une vue en coupe d'un élément modulaire de coffrage selon un mode de réalisation.
• La figure 16 est une vue en coupe d'un élément modulaire de coffrage selon un second mode de réalisation.
• La figure 17 est une vue en coupe d'un élément modulaire de coffrage selon un troisième mode de réalisation.
• La figure 18 est une vue en perspective d'un rabot permettant d'araser la surface supérieure des secteurs isolants en mousse projetée.
• La figure 19 est une représentation schématique illustrant des plots d'ancrage et un élément modulaire de coffrage équipé d'organes de fixation aux plots d'ancrage.
• La figure 20 est une vue de côté illustrant un plot d'ancrage et un élément modulaire de coffrage pourvu d'organes de fixation audit plot d'ancrage, selon un mode de réalisation.
• La figure 21 est une vue en perspective illustrant un plot d'ancrage pourvu de rainures pour la fixation des éléments modulaires de coffrage, selon un autre mode de réalisation.
• La figure 22 est une vue de dessus d'un élément modulaire de coffrage pourvu de pattes de fixation destinés à coopérer avec les rainures du plot d'ancrage illustré sur la figure 21.
• La figure 23 est une vue en perspective illustrant la fixation entre le plot d'ancrage de la figure 21 et l'élément modulaire de coffrage de la figure 22.
• La figure 24 est une vue en perspective illustrant des éléments modulaires de coffrage équipés d'organes de fixation à la structure porteuse.
• La figure 25 est une vue, de l'extérieur, d'un élément modulaire de coffrage de la figure 24.
• La figure 26 est une vue en perspective d'un élément modulaire de coffrage de la figure 24.
• La figure 27 est une représentation schématique écorchée d'une cuve de navire méthanier et d'un terminal de chargement/déchargement de cette cuve.

On these drawings:

• The figure 1 is a perspective view of modular formwork elements defining with a plurality of anchor pads and a carrier structure compartments for receiving projected foam.
• The figure 2 is a perspective view, similar to that of the figure 1 in which foam has been projected into the compartments.
• The figure 3 is a perspective view, similar to that of the figure 2 in which the modular formwork elements have been removed.
• The figure 4 is a perspective view, similar to that of the figure 3 wherein junction insulators have been disposed between the projected foam sectors.
• The figure 5 is a top view showing projected foam sectors, anchoring pads and insulating junction elements disposed between said projected foam sectors.
• The figure 6 is a perspective view of an anchor pad according to a first embodiment.
• The figure 7 is a perspective view of an anchor pad according to a second embodiment, adapted for the manufacture of a wall having successively two levels, primary and secondary, sealing and thermal insulation.
• The figure 8 is a top view showing anchor pads and anchor plates for fixing a waterproofing membrane.
• The figure 9 is a side view of an anchor pad supporting anchor plates.
• The figure 10 is a side view of an anchor pad according to a third embodiment.
• The figure 11 is a side view of an anchor pad according to a fourth embodiment.
• The figure 12 is a detailed illustration of the anchor pad of the figure 11 .
• The figure 13 is a schematic sectional view of an insulating junction element according to one embodiment.
• The figure 14 is a schematic sectional view of an insulating junction element according to another embodiment.
• The figure 15 is a sectional view of a modular formwork element according to one embodiment.
• The figure 16 is a sectional view of a modular formwork element according to a second embodiment.
• The figure 17 is a sectional view of a modular formwork element according to a third embodiment.
• The figure 18 is a perspective view of a plane for scoring the upper surface of the projected foam insulating sectors.
• The figure 19 is a schematic representation illustrating anchor pads and a modular formwork element equipped with fixing members anchor pads.
• The figure 20 is a side view illustrating an anchor pad and a modular formwork element provided with fixing members to said anchor pad, according to one embodiment.
• The figure 21 is a perspective view illustrating an anchor pad provided with grooves for fixing the modular formwork elements, according to another embodiment.
• The figure 22 is a top view of a modular formwork element provided with fixing lugs intended to cooperate with the grooves of the anchor pad illustrated on FIG. figure 21 .
• The figure 23 is a perspective view illustrating the attachment between the anchor pad of the figure 21 and the modular formwork element of the figure 22 .
• The figure 24 is a perspective view illustrating modular formwork elements equipped with fasteners to the supporting structure.
• The figure 25 is a view, from the outside, of a modular formwork element of the figure 24 .
• The figure 26 is a perspective view of a modular formwork element of the figure 24 .
• The figure 27 is a cutaway schematic representation of a tank of LNG tanker and a loading / unloading terminal of this tank.

By convention, the terms "external" and "internal" are used to define the relative position of one element relative to another, with reference to the interior and exterior of the vessel.

Each tank wall has successively, in the direction of the thickness, from the inside to the outside of the tank, at least one sealing membrane in contact with the fluid contained in the tank, a thermally insulating barrier and a supporting structure. In a particular embodiment, the wall has two levels of sealing and thermal insulation. In this case, the wall comprises successively, from the inside to the outside, a primary sealing membrane, a primary insulation barrier, a secondary sealing membrane, a secondary insulation barrier and a carrier structure. The terms "primary" and "secondary" are then used to qualify elements belonging to the primary and secondary levels.

With reference to Figures 1 to 4 , there is described a method of manufacturing a waterproof wall and thermally insulating according to one embodiment. Such sealed walls make it possible to make a containment vessel or tank for storing and / or transporting a cryogenic fluid, such as a liquefied gas, for example methane.

Anchor studs 1, also called couplers, are regularly positioned and fixed on an external support structure 2. This supporting structure 2 may in particular be a self-supporting metal sheet or more generally any type of rigid partition having appropriate mechanical properties, such as a concrete wall in a land construction.

Modular formwork elements 3 are arranged against the supporting structure 2 between the anchoring studs 1. The modular formwork elements 3 thus have a protruding shape, towards the inside, with respect to the plane of the supporting structure 2. Modular formwork elements 3 form, with the anchoring studs 1 and the supporting structure 2, a plurality of compartments 4. The compartments have an open side opposite to the supporting structure 2. The modular formwork elements 3 are longitudinal beams arranged perpendicularly to each other so as to form compartments 4 having the shape of quadrilaterals at right angles. The modular formwork elements 3 may be equipped with releasable fasteners, which will be described later in connection with the Figures 19 to 26 , making it possible to fix them to the supporting structure 2 and / or to the anchoring studs 1.

As illustrated on the figure 2 the compartments 4 are then filled by foam spraying through the open side of the compartments to form a plurality of insulating insulating foam sectors 5 projected. Compartments 4 therefore define a template for the realization of said insulating sectors 5. The projected foam is, for example, a polyurethane foam. In one embodiment, short fibers, such as glass fibers, are projected simultaneously, during the projection of the foam. Such an addition of fibers helps to reduce the thermal contraction of the foam during the cold setting of the tank.

Subsequently, the inner surface of the projected foam insulating sectors 5 undergoes a shaving operation. This operation makes it possible to eliminate the unevenness of the surface and thus to level the internal surface of the insulating sectors 5. The shaving operations are, for example, carried out by means of a plane 6, illustrated on FIG. figure 18 . Such a plane 6 is typically provided with handles, front 61 and rear 62, a sole 63 intended to cooperate with the surface to be leveled and a tool 64 flush with the sole 63 and for machining surface unevenness. In the embodiment, the tool 64 is a roller provided with blades or a milling cutter and rotated by a motor. In one embodiment, the planing tool is an automated tool whose movement is guided by guiding means, such as cables or belts, which are fixed on the anchoring studs 1. Moreover, in a advantageous embodiment, a suction system for recovering the dust is implemented during the shaving operations.

On the figure 3 Modular formwork elements 3 are removed. At this stage, the insulating sectors are separated by interstices 7 formed at the previous locations of the modular formwork elements 3.

In order to ensure a continuity of the thermal insulation, the interstices 7 between the insulating sectors 5 are filled with insulating elements of junction 8, represented on the Figures 4 and 5 . The insulating elements 8 of junction are furthermore arranged, at ambient temperature, under compressive stress, between the insulating sectors 5. Thus, said insulating elements 8 of junction are able to relax and fill the gap between the insulating sectors 5 when those they contract under the effect of low temperatures.

According to one embodiment, the insulating elements 8 of junction are strips made of a flexible material such as glass wool, polyester wadding, polyurethane (PU) foam, melamine, polyethylene (PE), polypropylene (PP) or silicone. The width of these strips is determined such that, at room temperature, they undergo a compressive stress between the insulating sectors 5.

According to other embodiments, illustrated on the Figures 13 and 14 , the insulating elements 8 of junction are profiles having two elastic lips 29. The elastic lips 29 have an elasticity and dimensions such that, at room temperature, they undergo a compressive stress between the insulating sectors 5. In other words in their constrained position, the elastic lips 29 are constrained by the insulating sectors towards their relative approximation and exert a reaction force tending to move said elastic lips 29. Said elastic lips 29 can be connected at their center so that the profile substantially has a shape of H ( figure 13 ) or be connected at one of their ends so that the profile is substantially U-shaped ( figure 14 ). In order to facilitate the positioning of the insulating elements 8 of junction before their disposition in the position of stress, they can be provided with releasable means of prestressing. Such means are for example links 30 bringing the elastic lips together. After breaking said connections 30, the elastic lips 29 are able to relax. Such insulating elements 8 junction are, for example made of polyurethane foam (PU), melamine, polyethylene (PE), polypropylene (PP), polystyrene (PS) or silicone.

In order to ensure the tightness of the wall, a sealing membrane 9, covering the insulating sectors 5 and the insulating elements 8 of junction, is fixed on the anchoring studs 1. Such a sealing membrane 9 is partially represented on the figures 9 , 10 and 11 . The sealing membrane 9 is composed of a plurality of plates, welded edge to edge, whose angles are fixed, by welding, on the anchoring studs 1. In known manner, the plates can be made of stainless steel and present series of perpendicular corrugations to absorb the forces due to the thermal contraction of the stainless steel or be made in Invar ®, that is to say an alloy of iron and nickel whose main property is to have a very low coefficient of expansion.

Thus, the method makes it possible to produce a wall comprising a sealing membrane 9 and a thermally insulating barrier. When the wall has two levels, primary and secondary, sealing and thermal insulation, the thermally insulated barrier and the sealing membrane 9 thus formed are secondary components and the process is repeated by arranging anchor pads 1 and modular elements 3 of formwork against the secondary waterproofing membrane 9 and then by injecting foam into compartments whose bottom is constituted by said secondary waterproofing membrane 9. Preferably, in this case, the waterproofing membrane secondary 9 is previously covered with a coating to prevent the sprayed foam does not adhere to the secondary waterproofing membrane 9 and thus causes additional mechanical stresses. This coating may have low adhesion and / or have a low mechanical strength so that it breaks when subjected to low stresses and, therefore, does not transmit significant forces between the membrane and the foam projected.

The Figures 6 to 11 illustrate anchoring means according to various embodiments.

The figure 6 represents an anchor pad 1 comprising a rigid thermal insulation layer 10. This rigid insulation layer 10 may in particular be made of plywood or insulating foam, such as a polyurethane foam, having a density higher than 100 kg / m ³ , for example of the order of 130 kg / m ³ . This rigid insulation layer 10 is here sandwiched between two plywood panels 10, 11 optional. A stud 13, fixed on the supporting structure 2, by welding for example, allows the attachment of the anchor pad 1 to the supporting structure 2. To do this, the outer plywood panel 12 is provided with a receiving orifice of said stud 13. The anchor pad 1 has a well for introducing a nut 14 to be screwed onto the threaded portion of the stud 13. When the nut 14 has been positioned, the well is advantageously filled by an insulating connector 15 having a shape corresponding to the well. Subsequently, a plate 16 of metal sheet, allowing the fixing by welding of the plate angles of the sealing membrane 9, is fixed on the anchor pad 1. The sheet metal plate 16 is here fixed on the internal plywood panel 11 by riveting.

The figure 7 represents a secondary anchor pad 1, adapted for the manufacture of a wall having successively two levels, primary and secondary. The anchor pad 1 is fixed to the supporting structure 2 in a manner similar to the anchor pad shown in FIG. figure 7 . However, in this embodiment, the nut 14 cooperating with the threaded portion of the pin 13 also cooperates with a threaded rod 16. The rod 16 passes through the insulating connector 15 via a bore provided for this purpose. The rod 16 has an outer end cooperating by screwing with the nut 14 and an inner end carrying a collar pin 17, metal. The flange of the stud 17 allows the fixing by welding of the angles of the plates of the sealing membrane 9. Moreover, the stud 17 makes it possible to fix a primary anchor pad 1, not shown, coming, by stacking, on the stud anchor 1 secondary, shown on the figure 7 . The primary anchor pad 1 may in particular be similar to the anchor pad 1 of the figure 6 and its fixing on the bolt 17 of the secondary barrier anchor post 1 is ensured in the same manner as described in relation to the bolt 13 fixed to the carrier structure 2.

The anchor pad 1, illustrated on the figure 10 , comprises a rigid insulation layer 10 and an outer plywood panel 12. The fixing of the anchor pad 1 is also carried out via a pin 13, fixed to the supporting structure 2, and a nut 14 cooperating with a portion threaded of said stud 13. The fixing of the plates of the sealing membrane 9 is provided via a metal cover 18 whose mounting on the anchor pad 1 is provided by sliding. The cover 18 has an outer face 180 extended by side wings 181, 182 extending on either side of said anchor pad 1. The lateral wings 181, 182 have curved edges 183, 184 sliding in grooves 19 20 formed in the lateral faces of the anchor pad 1.

The figures 11 and 12 illustrate an alternative embodiment of the support means and fixing, by welding, the plates of the sealing membrane 9. In this embodiment, a metal washer 21, intended to receive the corners of the sealing membrane plates 9 , is mounted on the stud 13 by means of a sealing member 22, shown in detail on the figure 12 . The sealing member 22 has an inner member 220 and an outer member 221. The inner member 220 has a threaded bore 224 for attachment to the stud 13. On the other hand, the inner member 220 has a threaded nipple 222 through an orifice formed in the metal washer 21 and cooperating with a threaded bore 223 formed in the outer member 221. In order to seal the assembly, the outer member 221 is a metal element fixed by a weld bead 225 on the metal washer 21. The outer member 221 is here provided with a bore 226 for receiving a stud for fixing a primary anchor pad, not shown. Advantageously, the inner member 220 may be made of a material having thermal insulation properties.

In order to ensure a better anchoring of the sealing membrane 9, anchoring plates 23, represented on the Figures 8 and 9 , can be used. The anchoring plates 23 consist of metal strips fixed on the anchoring studs 1. Also, the anchoring studs 1 have, on their inner face, a metal plate 24 intended for fixing said anchoring plates 23. The anchor plates 23 extend along the edges of the metal plates of the sealing membrane 9, said edges being fixed, by continuous or discontinuous welding, on the anchoring plates 23. At the junction between two adjacent metal plates, it can be provided a single anchor plate 23 for fixing one of the two metal plates or two anchor plates 23, as on the figure 8 , each of the two anchor plates 23 then serving to fix a respective metal plate of the sealing membrane 9. In one embodiment, the metal plate 24 for fastening said anchoring plates 23 and the flange stud 17 can be made in one piece.

The Figures 15 to 17 illustrate alternative embodiments of the modular formwork elements.

On the figure 15 , the modular formwork element 3 is a beam, made of wood, metal or plastic, having a non-stick coating. The non-stick coating is here a film 25 capable of dissociating itself from the modular formwork element 3 during its removal. Alternatively, the modular formwork element 3 may, in whole or in part, be made of a non-stick material such as polytetrafluoroethylene (PTFE). In such a case, the presence of a film becomes superfluous.

On the figure 16 , there is shown a combined element comprising a modular formwork element 3 and an insulating junction element 8. Such combined elements are put in place on the supporting structure 2. The modular formwork element 3 comprises two flanks 26 secured to one another. to one another and between which is housed, under stress, an insulating element 8 junction as described above. During the removal of the modular formwork element 3, an outward thrust force, for example via a not shown pusher device, is exerted on the insulating element 8 of junction so that, during the withdrawal of modular elements 3, the insulating elements 8 junction are left between the insulating sectors 5 foam projected. As previously, the insulating elements 8 of junction are, at ambient temperature, constrained between the insulating sectors 5 and able to relax so as to be able to fill the gap due to the thermal contraction of the insulating sectors 5 during the cold setting of the tank.

A combined element comprising a modular formwork element 3 and a junction insulating element 8 is illustrated in FIG. figure 17 . This combined element presents a different implementation of the combined element of the figure 16 since it is intended to remain, at least in part, permanently in the wall. The modular element 3 comprises two flanks 27 of lost formwork between which an insulating element 8 of junction is housed under stress. Since the flanks 27 are intended to form an integral part of the thermally insulating barrier, they are made of an insulating material, made of plywood, for example. The modular formwork element 3 comprises releasable means for clamping the flanks, strips 28 in the embodiment shown. When the foam has been sprayed and the insulating sectors 5 formed, the strips 28 can then be cut out so as to release the insulating element 8 from the junction. The latter is then in a constrained position, compressed between the insulating sectors 5, in which it is able to relax during thermal contraction of the insulating sectors 8 of projected foam.

The Figures 19 to 26 illustrate liberal members for fixing the modular formwork elements 3. Such fasteners are used to fix the modular formwork elements 3, in particular for the production of vertical walls or the ceiling of the tank. Of course, the fasteners must be liberal to allow the removal of said modular formwork elements 3.

On the figure 19 , the modular formwork element 3 is equipped with fastening tabs 31a, 31b on the anchoring studs 1 according to two embodiments. The fastening tabs 31a, 31b are profiled pieces having profiles of complementary shape to at least a portion of the profile of said anchoring studs 1. The fixing tabs 31a, 31b are arranged so as to cooperate with the upper face. anchor pad 1 and thus form retaining hooks of the modular formwork elements 3. The fixing lugs 31a, 31b may be made of metal or plastic.

In one embodiment, not shown, the fasteners may comprise strips capable of fixing the modular formwork elements 3 to the anchoring studs 1.

On the figure 20 , the modular formwork element 3 comprises a fastening lug 32 provided with an orifice intended to receive a stud 17 projecting from the inner face of the anchor pad 1. Advantageously, the stud 17 for fastening the elements modular formwork 3 can also ensure the attachment of said anchor pad 1 to the supporting structure 2. The stud 17 may comprise a threaded portion so as to allow the establishment of a nut, not shown, adapted to retain the tab fixing 32 against the inner face of the anchor pad 1.

In the embodiment of Figures 21 to 23 , the anchor pad 1 comprises two grooves 33 adapted to receive two tabs 34 of complementary shapes, formed at least one end of the modular elements 3 formwork. The grooves 33 open on the inner face of the anchoring studs 1.

Note also that, in this embodiment, the modular elements 3 formwork are equipped with handles 35 facilitating their handling and their establishment against the supporting structure 2.

In the embodiment of Figures 24 to 26 , the modular elements 3 formwork are equipped with fasteners to the supporting structure 2. The fasteners to the supporting structure here comprise tabs 36 formed on the outer face of the modular elements 3 formwork. The tongues 36 are provided with orifices intended to receive bolts fastened, for example by welding, to the supporting structure 2. The studs are advantageously threaded so as to receive a nut. In this case, the modular formwork elements 3 are at least partly hollow so as to allow access to the nuts via their inner face.

The method of manufacturing a wall, described above, can be used for the manufacture of one, more or all of the walls of a sealed and thermally insulating tank for storing and / or transporting fluid. cryogenic.

According to one embodiment, the method is applied to a planar bearing wall placed horizontally. Once the insulating barrier and the waterproofing membrane have been made on this flat wall, it constitutes a tight and insulating wall that can be handled in one piece. It is then possible to manufacture a polyhedric tank by assembling several carrier walls assembled to each other to form a tank, namely for example a bottom wall, side walls and a ceiling wall. The process can then be applied to achieve the insulating barrier and the sealed membrane on each of the carrier walls.

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.

With reference to the figure 27 , a cutaway view of a LNG tanker 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.

The figure 27 represents 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 an 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 connect to the loading / unloading pipes 73. The movable arm 74 can be adapted to all gauges 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 as defined by the claims.

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 (18)

1. A method for producing a sealed and thermally insulating wall for a fluid storage tank, comprising the steps of:

   • attaching a plurality of anchoring elements (1) to a support structure (2);

   • installing modular formwork elements (3) on the support structure (2), the modular formwork elements (3) having a shape that protrudes relative to the support structure (2) and that defines, with the support structure (2) and the plurality of anchoring parts (1), mutually adjacent compartments (4) having an open side opposite the support structure (2), two mutually adjacent compartments being separated in each case by a modular formwork element positioned between them;

   • spraying insulating foam into said compartments (4) through the open side so as to form a plurality of insulating sectors (5) made from sprayed insulating foam;

   • withdrawing the modular formwork elements (3);

   • arranging compressible insulating junction elements (8) in place of the modular formwork elements (3), the insulating junction elements (8) being arranged in a stressed position in which they are stressed between said insulating sectors (5) and capable of expanding when said insulating sectors (5) contract, so as to ensure continuity of the thermal insulation; and

   • attaching a sealing membrane (9) to said anchoring elements (1).
2. A method for producing a sealed and thermally insulating wall for a fluid storage tank, comprising the steps of:

   • attaching a plurality of anchoring elements (1) to a support structure (2);

   • installing combined elements on the support structure (2), each combined element comprising a modular formwork element (3) and a compressible insulating junction element (8), housed under stress within the modular formwork element (3); the modular formwork elements (3) having a shape that protrudes relative to the support structure (2) and that defines, with the support structure (2) and the plurality of anchoring parts (1), mutually adjacent compartments (4) having an open side opposite the support structure (2), two mutually adjacent compartments being separated in each case by a modular formwork element positioned between them;

   • spraying insulating foam into said compartments (4) through the open side so as to form a plurality of insulating sectors (5) made from sprayed insulating foam;

   • withdrawing the modular formwork elements (3); the insulating junction elements (8) being left, in a stressed position, between said insulating sectors (5) when the modular formwork elements (3) are withdrawn, the insulating junction elements (8) being, in their stressed position, stressed between said insulating sectors (5) and capable of expanding when said insulating sectors (5) contract, so as to ensure continuity of the thermal insulation; and

   • attaching a sealing membrane (9) to said anchoring elements (1).
3. A method for producing a sealed and thermally insulating wall for a fluid storage tank, comprising the steps of:

   • attaching a plurality of anchoring elements (1) to a support structure (2);

   • installing combined elements on the support structure (2), each combined element comprising a modular formwork element (3) and a compressible insulating junction element (8), the modular formwork element (3) having two permanent formwork sides (27) between which the insulating junction element (8) is housed under stress, and releasable means (28) for clamping the sides (27), these means being capable of clamping the two permanent formwork sides (27) against the insulating junction element (8) in a non-released state and of no longer clamping the two permanent formwork sides (27) in a released state; the modular formwork elements (3) having a shape that protrudes relative to the support structure (2) and that defines, with the support structure (2) and the plurality of anchoring parts (1), mutually adjacent compartments (4) having an open side opposite the support structure (2), two mutually adjacent compartments being separated in each case by a modular formwork element (3) positioned between them;

   • spraying insulating foam into said compartments (4) through the open side so as to form a plurality of insulating sectors (5) made from sprayed insulating foam;

   • releasing the means (28) for clamping the sides (27) so as to place the insulating junction elements (8) in a stressed position in which they are stressed between said insulating sectors (5) and capable of expanding when said insulating sectors (5) contract, so as to ensure continuity of the thermal insulation; each insulating junction element (8), in its stressed position, causing the two permanent formwork sides (27) of the combined element to which it belongs to engage with the insulating sectors (5) between which said two permanent formwork sides are located; and

   • attaching a sealing membrane (9) to said anchoring elements (1).
4. The production method as claimed in any of claims 1 to 3, wherein a modular formwork element (3) has an anti-adhesion coating (25).
5. The production method as claimed in any of claims 1 to 4, wherein an insulating junction element (8) comprises a profiled element having two resilient flanges (29) which, in a stressed position between the insulating sectors (5), are stressed toward one another and exert a reactive force tending to separate them from one another.
6. The production method as claimed in claim 5, wherein the profiled element having two resilient flanges is produced from a foam made of a polymer selected from among polyurethane, melamine, polyethylene, polypropylene, polystyrene and silicone.
7. The production method as claimed in any of claims 1 to 4, wherein an insulating junction element (8) comprises a strip made of a compressible material selected from among glass wool, polyester wadding, and foams of polyurethane, melamine, polyethylene, polypropylene or silicone.
8. The production method as claimed in any of claims 1 to 7, comprising a step of trimming the insulating sectors (5).
9. The production method as claimed in any of claims 1 to 8, wherein an anchoring element is a block (1) fitted with a member (13, 14) for anchoring to the support structure (2) and an element (16, 17, 18, 21) for attaching the sealing membrane (9), and having at least one thermally insulating layer (10).
10. The production method as claimed in claim 9, wherein the thermally insulating layer (10) of the block (1) is made of polymer foam having a density of more than 100 kg/m³, or of wood.
11. The production method as claimed in claim 9 or 10, comprising a step of attaching anchoring plates (23) between the adjacent anchoring blocks (1) and a step of welding the sealing membrane (9) onto said anchoring plates (23).
12. The production method as claimed in any of claims 1 to 11, wherein, during the installation of modular formwork elements (3) on the support structure (2), the modular formwork elements (3) are attached to the support structure (2) and/or to the anchoring elements (1).
13. A sealed and thermally insulating wall for a cryogenic fluid storage tank, made by a production process as claimed claim 1 or 2, comprising:

    • a support structure (2);

    • a plurality of anchoring elements (1), attached to the support structure (2);

    • a plurality of insulating sectors made of insulating foam, produced by spraying insulating foam against the support structure (2), each insulating sectors (2) occupying the intor space of a compartment defined by the support structure (2), the plurality of anchoring elements (1) and interstices separating the insulating sectors (5), the insulating sectors made of sprayed insulating foam adhering directly to the support structure (2);

    • insulating junction elements arranged in the interstices separating the insulating sectors (2) in a stressed position in which they are stressed between said insulating sectors and capable of expanding when said insulating sectors contract, so as to ensure continuity of the thermal insulation; and

    • a sealing membrane attached to said anchoring elements.
14. A sealed and thermally insulating wall for a cryogenic fluid storage tank, made by a production process as claimed claim 3, comprising:

    • a support structure (2);

    • a plurality of anchoring elements (1), attached to the support structure (2);

    • a plurality of insulating sectors made of insulating foam, produced by spraying insulating foam against the support structure (2), in a compartment defined by the support structure (2), the plurality of anchoring elements and combined elements separating the compartments, the insulating sectors made of sprayed insulating foam adhering directly to the support structure (2);

    • the combined elements each comprising a modular formwork element (3) and a compressible insulating junction element (8), the modular formwork element (3) having two permanent formwork sides (27) between which the insulating junction element (8) is housed under stress, in a stressed position in which they are stressed between said permanent formwork sides and capable of expanding when said insulating sectors contract, so as to ensure continuity of the thermal insulation and releasable means (28) for clamping the sides (27) in a non-released state in which they does not clamp the two permanent formwork sides (27); and

    • a sealing membrane attached to said anchoring elements.
15. A liquid storage tank comprising at least one wall as claimed in claim 13 or 14.
16. A ship (70) for transporting a refrigerated liquid product, the ship comprising a tank (71) as claimed in claim 15.
17. A method for loading or unloading a ship (70) as claimed in claim 16, wherein a refrigerated liquid product is conveyed through insulated pipes (73, 79, 76, 81) from or to a floating or land-based storage installation (77) to or from the tank of the ship (71).
18. A transfer system for a refrigerated liquid product, the system comprising a ship (70) as claimed in claim 16, insulated pipes (73, 79, 76, 81) arranged so as to connect the tank (71) installed in the ship's hull to a floating or land-based storage installation (77), and a pump for propelling a flow of refrigerated liquid product through the insulated pipes from or to the floating or land-based storage installation to or from the ship's tank.

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