FR3072759A1 - SEALED AND THERMALLY INSULATED TANK - Google Patents

Abstract

Sealing and thermally insulating tank for storing a fluid, comprising, at a ridge (100) between the supporting structure (5) of a first wall (1) and the supporting structure (25) of a second wall (2) , an angle structure (10), the angle structure having a sealing angle (13) fixed on the one hand to a first anchoring wing (11) via a first piece connection (12), and secondly to a second anchoring wing (211) via a second connecting piece (212), the sealing angle (13) being sealingly connected to the sealing membrane (27) of the first wall and to the sealing membrane (7) of the second wall.

Description

Watertight and thermally insulating tank

Technical area

The invention relates to the field of sealed and thermally insulating tanks. In particular, the invention relates to the field of sealed and thermally insulating tanks in the context of the storage or transport of liquid at low temperature such as ships' tanks for the transport of Liquefied Petroleum Gas (also called LPG) presenting by example a temperature between -50 ° C and 0 ° C, or for the transport of liquefied natural gas (LNG) at around -162 ° C at atmospheric pressure.

Technological background

Sealed and thermally insulating tanks for ships are known, for example, from document WO-A-2017064413. This document describes a propane or LNG tank comprising a plurality of tank walls. Each wall of the tank comprises at least one sealing membrane and at least one thermal insulation barrier.

Document JP2009079736 proposes a terrestrial tank for cryogenic liquid comprising a concrete support structure and a thermal insulation barrier including an M-shaped piece designed to adapt to the thickness of the thermal insulation barrier by changing the height. of an M-shaped part. However, the M-shaped part requires complicated shaping.

summary

An objective of the invention is to provide a corner structure capable of supporting one or more sealing membranes at an angle between two walls of the tank and capable of adapting to different thicknesses of the thermal insulation barrier .

The invention provides a sealed and thermally insulating fluid storage tank comprising a first wall and a second wall, the first and second walls each comprising, in a thickness direction, a load-bearing wall, an insulation barrier. thermal fixed to the support wall, a waterproofing membrane parallel to the support wall and fixed to the thermal insulation barrier, the sealed and thermally insulating tank comprising, at an edge between the support wall of the first wall and the support wall of the second wall, a corner structure, the corner structure comprising a first anchoring wing fixed to the load-bearing wall of the first wall, a second anchor wing fixed to the load-bearing wall of the second wall, a sealing angle fixed, on the one hand, to the first anchoring wing by means of a first connecting piece, and on the other hand, to the second wing anchoring via a second connecting piece. The sealing angle is tightly connected to the sealing membrane of the first wall and to the sealing membrane of the second wall, the sealing angle having a first planar branch extending in the plane of the sealing membrane of the second wall, and a second planar branch extending in the plane of the sealing membrane of the first wall, the first connecting part comprising a first planar branch parallel to the first anchoring wing, and a second planar branch parallel to the sealing membrane of the second wall, the second connecting part comprising a first planar branch parallel to the second anchoring wing, and a second planar branch parallel to the sealing membrane of the first wall, the first planar branch of the first connecting part being welded to the first anchoring wing, the first branch flat che of the second connecting part being welded to the second anchoring wing, the first flat branch of the sealing angle being welded to the second flat branch of the first connecting part, and the second flat branch of the angle of sealing being welded on the second planar branch of the second connecting piece, the sealing membrane of the first wall being welded on the second planar branch of the sealing angle, and the sealing membrane of the second wall being welded to the first flat branch of the sealing angle.

This angle structure makes it possible to adjust the position of the angle sealing membranes by adapting the position of the anchoring of the connecting pieces on the anchoring wings to the desired position of the sealing angle. This adjustment of the position of the sealing angle allows the angle structure to be easily adapted to the thickness of the insulation barriers of the tank walls. Indeed, the position of the first planar branch of the first connecting piece on the first anchoring wing makes it possible to adjust the distance between the second planar branch of the first connecting piece and the load-bearing wall of the second wall and therefore between the first planar branch of the sealing angle and the supporting wall of the second wall. Likewise, the position of the second planar branch of the second connecting part on the second anchoring wing makes it possible to adjust the distance between the second planar branch of the second connecting part and the load-bearing wall of the first wall and therefore between the second planar branch of the sealing angle and the supporting wall of the first wall.

According to embodiments, such a tank may include one or more of the following characteristics.

According to some embodiments, the sealing angle comprises a plurality of cross sections, two adjacent cross sections being tightly connected to each other by means of a corrugated connection projecting in the direction of the inside of the tank, the sealing membrane of the first and of the second wall each comprising a series of undulations projecting towards the inside of the tank and developing in a direction perpendicular to the edge, each undulation of the first wall and the second wall being aligned with a corrugated connection of the sealing angle. Such corrugated connections are simple to produce and to fit on a corrugation of the first wall and on a corrugation of the second wall, so as to ensure the continuity of the seal between the sealing angle and the sealing membranes while being able to deform with the waterproofing membranes.

According to some embodiments, the sealing angle comprises a plurality of cross sections, two adjacent cross sections being tightly connected to each other by means of a corrugated connection projecting in the direction of the inside the tank, the sealing membrane of the first and of the second wall each comprising a series of undulations projecting towards the outside of the tank and developing in a direction perpendicular to the edge, each undulation of the first wall and the second wall being aligned with a corrugated connection of the sealing angle.

According to certain embodiments, a corrugated connector has a central part, a first bent end, and a second bent end, the first bent end fitting, on the one hand, on a corrugation of the sealing membrane of the first wall, and on the other hand, on the central part, the second bent end fitting, on the one hand, on a corrugation of the sealing membrane of the second wall, and on the other hand, on the central part . The fact that the corrugated fittings are in three parts simplifies the connection with the waterproofing membranes and makes it possible to correct any misalignments between the corrugations.

According to certain embodiments, the first anchor wing extends parallel to the load-bearing wall of the first wall, the second anchor wing extends parallel to the load-bearing wall of the second wall.

According to certain embodiments, at the edge, the load-bearing wall of the first and the load-bearing wall of the second wall together form a projecting angle on the inside of the tank, the first anchoring wing extending in the extension of the load-bearing wall of the first wall, and the second anchor wing extending in the extension of the load-bearing wall of the second wall.

According to certain embodiments, at the edge, the load-bearing wall of the first and the load-bearing wall of the second wall together form an angle returning from the inside of the tank, the first anchoring wing extending parallel to distance from the bearing wall of the first wall, the second anchoring wing extending parallel to the distance from the bearing wall of the second wall.

According to certain embodiments, the thermally insulating barrier of the first wall and / or of the second wall comprises a plurality of heat-insulating elements, each heat-insulating element comprising a cover panel turned towards the inside of the tank, the inside face of the heat-insulating element bordering the edge comprising a recess vis-à-vis the sealing membrane, a connection plate being housed in the recess and flush with the interior face of the heat-insulating element and the face inside of the flat branch of the sealing angle to which the waterproofing membrane is fixed in order to form a continuous flat support surface for the waterproofing membrane.

According to certain embodiments, slots are provided in the first anchor wing and / or in the second anchor wing, the slots being arranged at the level of the corrugated connections. These slots make it possible to at least partially limit the mechanical stresses undergone by the welds between the corrugated fittings and the cross sections of the sealing angle.

According to certain embodiments, the thermal insulation barrier fixed to the load-bearing wall is a secondary thermal insulation barrier, the waterproofing membrane fixed to the secondary thermal insulation barrier being a secondary waterproofing membrane, the angle iron sealing connected in leaktight manner to the secondary sealing membrane of the first wall and to the secondary sealing membrane of the second wall being a secondary sealing angle, the first and the second wall comprising, in addition, in the thickness direction of the tank, from outside to inside, over the secondary thermal insulation barrier and the secondary waterproofing membrane, a primary thermal insulation barrier and a primary waterproofing membrane intended to be in contact with the liquid contained in the tank, the corner structure further comprising an angle iron Primary seal sealingly connected to the primary seal membrane of the first wall and to the primary seal membrane of the second wall.

According to certain embodiments, the primary sealing angle is fixed to the secondary sealing angle by means of one or more spacers.

According to certain embodiments, an outer face of the primary sealing angle carries primary studs, each spacer comprising at least one orifice traversed by a primary stud, the spacer being held in abutment against the external face of the angle primary sealing by a primary nut mounted on the primary stud, an inner face of the secondary sealing angle carrying secondary studs, a spacer having fixing lugs, a secondary stud being positioned between the fixing lugs of two adjacent spacers, a support plate comprising an orifice being mounted on the secondary stud, the two adjacent spacers being held in abutment by said support plate against an inner face of the secondary sealing angle by a secondary nut mounted on the secondary stud.

According to certain embodiments, the secondary sealing membranes are composite membranes, the secondary sealing angle comprising a plurality of cross sections, two adjacent cross sections being tightly connected to each other by means of a composite sealing strip.

According to certain embodiments, the composite sealing strips are glued between the angles.

Such a tank can be part of a terrestrial storage installation, for example for storing liquefied gas or be installed in a floating structure, coastal or deep water, in particular an LNG tanker, an LPG transport ship, a floating unit storage and regasification (FSRU), a floating production and remote storage unit (FPSO) and others.

According to one embodiment, a ship for transporting a cold liquid product comprises a hull and aforementioned tank disposed in the hull.

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

According to one embodiment, the invention also provides a transfer system for a cold liquid product, the system comprising the aforementioned ship, isolated pipes arranged so as to connect the tank installed in the hull of the ship to a floating storage installation. or terrestrial and a pump to drive a flow of cold liquid product through the isolated pipes from or to the floating or terrestrial storage facility to or from the vessel of the ship.

Brief description of the figures

The invention will be better understood, and other objects, details, characteristics and advantages thereof will appear more clearly during the following description of several particular embodiments of the invention, given solely by way of illustration and without limitation. , with reference to the accompanying drawings.

• Figure 1 is a perspective view of a tank according to an embodiment of the invention.

• Figure 2 is a perspective view of a portion of the tank of Figure 1 illustrating the gas dome seen from the inside of the tank.

• Figures 3 to 6 are perspective views of a projecting corner structure according to an embodiment of the invention during different stages of its construction.

• Figure 7 is a sectional view of the corner structure of Figure 6.

• Figures 8 to 11 are sectional views of a corner structure for a tank having two sealing membranes interposed with two thermal insulation barriers, according to different embodiments of the invention. In particular, Figures 9 and 10 illustrate a particular embodiment of anchoring the primary sealing angle to the secondary sealing angle, Figure 10 being a sectional view in the plane of two studs fixed to the angle primary sealing while Figure 9 is a sectional view in the plane of two studs attached to the secondary sealing angle. FIGS. 10b to 10f are sectional views in a plane perpendicular to the primary sealing angle and parallel to the edge and illustrate the different stages of a particular embodiment of the mounting of the primary sealing angle on the secondary sealing angle. FIG. 11 illustrates an alternative embodiment for anchoring the primary sealing angle to the secondary sealing angle.

• Figure 12 is a side view of a sealing angle.

• Figure 13 is a sectional view of a re-entrant angle structure according to another embodiment of the invention.

• Figure 14 is a cutaway view of an LNG or propane vessel comprising a tank according to an embodiment of the invention.

• Figure 15 is a partial perspective view of a projecting corner structure according to certain embodiments of the invention.

Detailed description of embodiments

The figures are described below in the context of a load-bearing structure constituted by the internal walls of a double hull of a ship for the transport of liquefied gas. Such a supporting structure may in particular have a polyhedral geometry, for example of prismatic shape. FIG. 1 illustrates such a support structure in which longitudinal walls, comprising an upper wall 104, a lower wall 105 and side walls 106, 107, 108, 109, 110, 111, of the support structure extend parallel to the longitudinal direction of the ship and form a polygonal section in a plane perpendicular to the longitudinal direction of the ship. The general structure of a ship fitted with such polyhedral tanks is for example described with reference to FIG. 1 of the document FR3008765.

The longitudinal walls 104, 105, 106, 107, 108, 109, 110, 111 are interrupted in the longitudinal direction of the ship by transverse bearing walls 101, 103 which are perpendicular to the longitudinal direction of the ship. The longitudinal walls 104, 105, 106, 107, 108, 109, 110, 111 and the transverse walls 101, 103 meet at reentrant edges.

Each wall of the supporting structure carries a respective vessel wall. In FIGS. 2 to 7, each of the tank walls is composed of a thermally insulating barrier carrying a sealing membrane in contact with a fluid stored in the tank such as liquefied petroleum gas comprising butane, propane, propene or other and having an equilibrium temperature for example between -50 ° C and 0 ° C.

The upper wall 104 has a space, for example of rectangular parallelepiped shape, projecting upwards, called liquid dome 112.

As illustrated in more detail in FIG. 2, the liquid dome 112 is defined by two transverse walls, front 113 and rear 114, and by two side walls 115, 116 which extend vertically and project from the upper wall 104 towards the high. The liquid dome 112 also comprises a horizontal cover, not shown in FIG. 2, which is intended to cover the opening made between the front 113, rear 114 and side walls 115, 116 of the liquid dome 112. The horizontal cover is crossed by a series of pipes intended to load or unload the liquids and gases previously quoted. The upper longitudinal wall 104 and the walls of the liquid dome 112 meet at protruding edges 100. The front 113 and side walls 115, 116 of the liquid dome 112 meet at re-entrant edges 201.

FIG. 3 is a view from inside the tank of a tank angle at a projecting edge 100 between a first support wall 5 and a second support wall 25 carrying respectively a first tank wall 1 and a second tank wall 2. The first support wall 5 and the second support wall 25 form an angle a between them. The first tank wall 1 and the second tank wall 2 meet at a corner structure 10 of the tank.

In particular, as will be described in relation to FIGS. 3 to 6, the corner structure 10 can be a projecting corner structure (the angle a towards the inside of the tank between the two load-bearing walls is between 180 ° and 360 °, so that the edge projects from the inside of the tank), which is for example the case between an edge between the upper longitudinal wall 104 and one of the front walls 113, rear 114 and side 115, 116 of the liquid dome 112. FIGS. 3 to 6 illustrate the particular case of an angle a of 270 °.

As will be described in relation to FIG. 13, the angle structure 10 can be a reentrant angle structure (the angle a is between 0 ° and 180 °, so that the edge is reentrant seen from l 'interior of the tank), which is for example the case between an edge 10 longitudinal walls 104, 105, 106, 107, 108, 109, 110, 111 and the transverse walls 101, 103. Figure 13 illustrates the special case of an angle a of 90 °.

As illustrated in FIG. 6, the first tank wall 1 comprises, in a thickness direction, a support wall 5, a thermal insulation barrier 6 fixed to the support wall 5, a sealing membrane 7 parallel to the support wall 5. The second tank wall 2 comprises, in a thickness direction, a support wall 25, a thermal insulation barrier 26 fixed to the support wall 25, a sealing membrane 27 parallel to the support wall 25.

As illustrated in FIG. 3, the thermal insulation barrier 6 of the first tank wall 1 consists of a plurality of heat-insulating elements 61 anchored on the first support wall 5. These heat-insulating elements 61 jointly form a flat surface on which is anchored the sealing membrane 27. Likewise, the thermal insulation barrier 25 of the second tank wall 2 consists of a plurality of heat-insulating elements 61 anchored on the second support wall 25. These heat-insulating elements 61 jointly form a flat surface on which the sealing membrane 7 is anchored. The heat-insulating elements 61 are anchored to the support structure by any suitable means.

In one embodiment, the heat-insulating elements 61 are produced in the form of boxes anchored to the support wall by studs, as described in the publication WO-A-2017064413.

As illustrated in FIG. 6, the sealing membrane 7, 27 is made up of a plurality of metal plates juxtaposed with each other with overlap. These metal plates are preferably rectangular in shape. The metal plates are welded together to ensure the sealing of the waterproofing membrane. The metal plates are for example made of stainless steel, an iron-based alloy with a high nickel or manganese content of 0.5 to 1.5 mm thick.

In order to allow the deformation of the waterproofing membrane in response to the various stresses undergone by the tank, in particular in response to the thermal contraction resulting from the loading of liquefied gas into the tank, the metal plates comprise a plurality of corrugations 71, 72 oriented towards the inside of the tank. More particularly, the sealing membrane 7 comprises a first series of corrugations 71 and a second series of corrugations 72 forming a regular rectangular pattern. The first series of corrugations 71 is perpendicular to the edge 100 and the second series of corrugations 72 is parallel to the edge 100. Preferably, the corrugations 71, 72 develop parallel to the edges of the rectangular metal plates. The distance between two successive undulations 71, 72 of a series of undulations is for example of the order of 300 mm to 800 mm and ideally 600 mm.

As illustrated by FIG. 3, the angle structure 10 comprises a first anchoring wing 11 extending from and in the extension of the bearing wall 5 of the first tank wall 1, and a second wing of anchor 211 extending from and in the extension of the load-bearing wall 25 of the second tank wall 2. The first anchor wing 11 may not extend in the extension of the load-bearing wall 5 of the first wall of tank 1 as long as it extends in a direction not parallel to the load-bearing wall 25 of the first wall 2. The row of heat-insulating elements 61 of the thermally insulating barrier 6 bordering the edge 100 are arranged so as to provide a space between the row of heat-insulating elements 61 bordering the edge 100 and the second anchor wing 211. Likewise, the second anchor wing 211 may not extend in line with the load-bearing wall 25 of of the second tank wall 2 as long as it extends in a direction not parallel to the load-bearing wall 5 of the first wall 1. The row of heat-insulating elements 61 of the thermally insulating barrier 26 bordering the edge 100 are arranged so as to provide a space between the row of heat-insulating elements 61 bordering the edge 100 and the first anchoring wing 11.

As illustrated in FIG. 4, the corner structure 1 comprises a first connection part 12 and a second connection part 212. The first connection part 12 comprises a first planar branch 122 fixed to the anchoring wing 11 and extending in the extension of the anchoring wing 11, and a second planar branch 121 extending parallel to the bearing wall 25 in the space provided between the first anchoring wing 11 and the row of heat-insulating elements 61 of the thermal insulation barrier 26 bordering the edge 100. The first connecting piece 12 can in particular be composed of a plurality of successive sections 125. Likewise, the second connecting piece 212 comprises a first planar branch 2122 fixed to the anchoring wing 211 and extending in the extension of the anchoring wing 211, and a second planar branch 2121 extending parallel to the load-bearing wall 5 in the space provided between the first anchoring wing 211 and the row of heat-insulating elements 61 of the thermal insulation barrier 6 bordering the edge 100. The second connecting piece 212 can in particular be composed of a plurality of successive sections 215. The connecting piece 12, 212 is welded indifferently to the face of the anchoring wing 11, 211 facing the insulating blocks 61 of the tank wall 1 or 2. As illustrated in FIG. 7, the connecting pieces 12 and 212 may include a reinforcement between their two planar branches to increase their rigidity.

The spaces provided between the first anchoring wing 11, the row of heat-insulating elements 61 of the thermal insulation barrier 26 bordering the edge 100, the second planar branch 121 and the load-bearing wall 25 are advantageously filled with heat-insulating lining such than glass wool or polyurethane foam. The spaces provided between the second anchoring wing 211, the row of heat-insulating elements 61 of the thermal insulation barrier 6 bordering the edge 100, the second planar branch 211 and the load-bearing wall 5 are advantageously filled with heat-insulating lining such than glass wool or polyurethane foam.

As illustrated in FIG. 5, the corner structure 10 further comprises a sealing angle 13 fixed, on the one hand, to the first anchoring wing 11 by means of the first connecting piece 12, and on the other hand, to the second anchor wing 211 via the second connecting piece 212.

The sealing angle 13 is a plate, for example metallic, having a thickness greater than that of the sealing membrane 7, 27. The sealing angle 13 has for example a thickness of between 3 mm and 10 mm. gives sufficient rigidity to support itself, which is not necessarily the case with the sealing membranes 7, 27.

The sealing angle 13 comprises a first planar branch 131 extending in the plane of the sealing membrane Ί of the second tank wall 2, and a second planar branch 132 extending in the plane of the membrane tightness 27 of the first tank wall 1. The first planar branch 131 is fixed to the first connecting part 12 (more precisely welded to the second planar branch 121 of the first connecting piece 12), and the second planar branch 132 is welded to the second connecting piece 212 (more precisely welded to the second planar branch 2121 of the second connecting piece 212). As illustrated in FIG. 12, the sealing angle 13 may include a reinforcement 134 on its outer face.

Such a corner structure makes it possible to adjust the position of the sealing angle 13 by adapting on the one hand the position of the anchoring of the first planar branches 122, 2122 of the connecting pieces 12, 212 on the wings of anchoring 11, 211 and on the other hand the position of the anchoring of the flat branches 131, 132 of the sealing angle 13 on the second flat branches 121, 2121 of the connecting pieces 12, 212. This adjustment of the position of the sealing angle 13 allows the angle structure to be easily adapted to the thickness of the heat-insulating elements 61 of the insulation barriers 6, 26.

The first branch 131 of the sealing angle forms a flat support for the sealing membrane 7 of the second tank wall 2, and the second branch 132 of the sealing angle forms a flat support for the sealing membrane 27 of the first tank wall 1.

As illustrated in FIG. 6, the sealing membrane 7 of the second wall rests on the first branch 131 of the sealing angle 13. The sealing membrane 27 of the first wall rests on the second branch 132 of the angle sealing 13. To ensure continuity between the sealing membrane 7 of the second wall and the sealing membrane 27 of the first wall at the corner structure 10, the sealing angle 13 is connected sealingly to the sealing membrane 7 of the second wall and to the sealing membrane 27 of the first wall. For example, the sealing membrane 7 of the second wall can be welded to the first branch 131 of the sealing angle 13 on which it rests, and the sealing membrane 27 of the first wall welded to the second branch 132 of the sealing angle on which it rests.

As illustrated in FIG. 5, the sealing angle 13 can comprise a plurality of transverse sections 135. The transverse sections 135 of the sealing angle are for example fixed in overlap on two adjacent sections 125 of the first connecting piece 12 and on two adjacent sections 215 of the second connecting piece 212.

As illustrated in FIG. 6, two adjacent cross sections 135 can be tightly connected to each other by means of a corrugated connection 15. Each corrugation of the first series of corrugations 71 of the first wall and of the second wall is aligned with a corrugated connection 15 of the sealing angle. The corrugated connector 15 fits on a corrugation 71 of the sealing membrane 27 of the first wall and on a corrugation 71 of the sealing membrane 7 of the second wall. The corrugated connections 15 allow the sealing angle 13 to deform with the sealing membranes 7, 27.

As best seen in Figure 7, the corrugated connector 15 has a central portion 153, a first angled end 151, and a second angled end 152. The central portion 153 has two side tabs, one of the side tabs being welded to the central portion 133 of a section 155 of the sealing angle, and the other lateral tab being welded to the central part of an adjacent section 155 of the sealing angle. The first bent end 151 fits on the one hand on a corrugation 71 of the first wall, and on the other hand on the central part 153. The first bent end 151 has two lateral tabs, one of the lateral tabs being welded to a section 155 of the sealing angle, and the other lateral tab being welded to the adjacent section 155 of the sealing angle, covering the overlapping zone between the sealing angle 13 and the sealing membrane 7 of the second tank wall 2. Likewise, the second bent end 152 has two lateral tabs, one of the lateral tabs being welded to a section 155 of the sealing angle, and the other lateral tab being welded to the adjacent section 155 of the sealing angle, covering the overlapping area between the sealing angle 13 and the sealing membrane 27 of the first wall of c uve 1.

Such corrugated connections 15 are simple to produce and to fit on a corrugation 71 of the first wall and on a corrugation 71 of the second wall, so as to ensure the continuity of the seal between the sealing angle 13 and the membranes sealing 7, 27, while being able to deform with the sealing membranes 7, 27. The fact that the corrugated connections 15 are in three parts simplifies the connection with the sealing membranes 7, 27 and makes it possible to correct misalignments between the corrugations 71.

As illustrated in FIG. 15, slots 119 are optionally provided in the first anchoring wing 11. Likewise, slots 2119 are optionally provided in the second anchoring wing 211. The slots 119 and / or 2119 can in particular be extend from the end of the anchoring wing 11, 211 in a direction perpendicular to the edge 100, and, in particular, over a distance equal to between and 2/3 of the dimension of the anchor wing 11, 211 in this direction. The slots 119 and / or 2119 can in particular be arranged at the level of the corrugated connections 15, that is to say typically every 600 mm. These slots 119, 2119 make it possible to release the mechanical stresses undergone by the welds between the corrugated fittings 15 and the cross sections 135 of the sealing angle 13.

As illustrated in FIG. 5, each heat-insulating element 61 comprises a cover panel turned towards the inside of the tank. By convention, the adjective "inside" applied to an element of the tank designates the part of this element oriented towards the inside of the tank and the adjective "outside" indicates the part of this element oriented towards the outside of the tank. tank, regardless of the orientation of the tank wall with respect to the earth's gravity field. On the side of the heat-insulating elements 61 immediately adjacent to the corner structure 10, the inner face of the cover panel has a recess 62 facing the connecting piece 12, 212. As illustrated in FIG. 6, a connecting plate 63 is housed in the recess 62 and is flush with the inside face of the heat-insulating element 61 and the inside face of the planar branch 132 of the sealing angle on which the sealing membrane is fixed 27 in order to form a continuous flat support surface for the sealing membrane 27. Furthermore, the connection plate 63 makes it possible to make up for the construction clearances which may appear during the construction of the tank. The connection plate 63 may also have a recess on its outer face, the first branch 2122 of the connecting piece 212 on which is fixed the planar branch 132 of the sealing angle coming to be received in the recess of the plate connection 63. The connection plate 63 is thus supported both on the internal face of the heat-insulating element 61 and on the internal face of the first branch 2122 of the connecting piece 212. The connection plate 63 is described in relationship with the first tank wall 1, but it is understood that a similar connecting plate can be provided on the second tank wall 2.

The technique described above for producing a tank having a single waterproofing membrane can be used in different types of tanks, for example to constitute a double membrane tank for liquefied natural gas (LNG) in a terrestrial installation or in a structure. floating like an LNG tanker or whatever. In this context, it can be considered that the waterproofing membrane illustrated in the previous figures is a secondary waterproofing membrane, and that a primary thermal insulation barrier as well as a primary waterproofing membrane must still be added on this secondary waterproofing membrane. In this way, this technique can also be applied to tanks having a plurality of thermally insulating barriers and superimposed waterproof membranes.

FIG. 8 shows two walls of the tank at an edge 100 according to an alternative embodiment in which the first tank wall comprises, in the thickness direction of its tank, from the outside towards the inside, a secondary thermal insulation barrier 6, which corresponds to the thermal insulation barrier 6 described in relation to the previous figures, a secondary waterproofing membrane 27, which corresponds to the waterproofing membrane 27 described in relation to the previous figures , a primary thermal insulation barrier 6 and a primary sealing membrane 9 intended to be in contact with the liquid contained in the tank. Likewise, the second tank wall 2 comprises, in the thickness direction of the tank, from the outside to the inside, a secondary thermal insulation barrier 26, which corresponds to the thermal insulation barrier described in in relation to the previous figures, a secondary waterproofing membrane 7, which corresponds to the waterproofing membrane 7 described in relation to the previous figures, a primary thermal insulation barrier 26 and a primary waterproofing membrane 29 intended to be in contact with the liquid contained in the tank.

The primary thermal insulation barrier 6, 26 and the primary waterproofing membrane 29, 9 may be similar to the secondary thermal insulation barrier 6, 26 and the secondary waterproofing membrane 27, 7 will not be described further. in detail.

In a version not shown, the primary sealing membranes 9, 29 are different from the secondary sealing membranes 7, for example, the undulations of its secondary sealing membrane 7, 27 can be turned towards the outside of the wall. tank.

In another version not shown, the primary sealing membranes 9,29 and the secondary sealing membrane 7, 27 have corrugations facing outwards from the tank wall

Another version not shown, the secondary sealing membranes 7, 27 are composite sealing barriers. A composite connecting strip is bonded on one side to the secondary sealing angle 13 on the second planar branch 132 and on the other to the composite sealing barrier present on the insulating blocks 61 above. Alternatively, the strip of composite connection may be glued on one side to the second connecting piece 212 and on the other to the composite sealing barrier present on the top of the insulating blocks 61. In order to ensure the sealing of the secondary barrier, composite sealing strips are glued between your angles 135. The composite sealing barrier can in particular be made of a composite material comprising three layers: the two outer layers are glass fiber fabrics and the intermediate layer is a thin metal foil, e.g. aluminum foil about 0.1mm thick. This metal sheet constitutes the secondary sealing barrier and it is bonded to the insulating blocks 61 of the thermal insulation barrier 6, 26. The composite bonding strips and the composite sealing strips can in particular be bonded with polyurethane or epoxy adhesive.

A primary sealing angle 913 is fixed to the secondary sealing angle 13, which corresponds to the sealing angle 13 described in relation to FIGS. 3 to 6. The primary sealing angle 913 will not be described in detail because it is similar to the sealing angle 13 described in relation to FIGS. 3 to 6. The primary sealing angle 913 is connected in leaktight manner to the primary sealing membrane 29 of the first tank wall 1 and to the primary sealing membrane 9 of the second tank wall 2.

Several possibilities exist for fixing the primary sealing angle 913 to the secondary sealing angle 13. As illustrated in FIGS. 9 to 11, the primary sealing angle 913 can in particular be fixed to the secondary sealing angle 13 by anchoring members 30.

As illustrated by FIGS. 9 and 10, the anchoring members 30 may comprise one or more spacers 32 fixed to the primary sealing angle 913 before the assembly formed by the spacers 32 and the primary sealing angle 913 does is fixed on the secondary sealing angle 13.

As illustrated in FIG. 9, the inner face of the secondary sealing angle 13 can carry secondary studs 31 fixed, by welding and / or screwing. Figure 9 is a sectional view in the plane of two studs 31 fixed to the secondary sealing angle 13. In particular, each cross section 135 of the secondary sealing angle 13 may include two studs 31. Each stud 31 is develops perpendicular to the central part 133 of the secondary sealing angle 13 towards the inside of the tank.

As illustrated in FIG. 10, the outer face of the primary sealing angle 913 can carry primary studs 35 fixed, by welding and / or screwing. Figure 10 is a sectional view in the plane of two studs 35 fixed to the primary sealing angle 913. In particular, each cross section of the primary sealing angle 913 may comprise two studs 35. Each stud 35 develops perpendicular to the central part of the primary sealing angle towards the outside of the tank.

An embodiment of the mounting of the primary sealing angle 913 on the secondary sealing angle 13 is now described in relation to FIGS. 10b to 10f.

As illustrated in FIG. 10b, each cross section 9135 of the primary sealing angle 913 has one or more primary studs 35. One end of the studs opposite the primary sealing angle 913 has a thread. Each spacer 32 has one or more orifices 322 extending from its inner face. In particular, each spacer 32 may have two orifices 322 extending from its inner face.

As illustrated in FIG. 10c, each spacer 32 is mounted on one or more studs 35 so that each orifice 322 of the spacer is crossed by a stud 35.

As illustrated in FIG. 10d, a nut 351 is mounted on the threaded end of each stud 35. The internal face of the spacer 32 is thus held in abutment by said nut 351 against the external face of the primary sealing angle 913. A chimney 321 formed in the spacer 32 in line with the orifice through which the stud 31 allows the nut 351 to be screwed onto the stud and is filled with an insulator after the nut 351 has been screwed.

As illustrated by FIGS. 10e and 10f, the external face of the spacer 32 (that is to say the face of the spacer 32 opposite the primary sealing angle 913) is then fixed by any means, by example bonding, riveting, or screwing, on the inner face of the secondary sealing angle 13.

As illustrated in Figure 10e, each cross section 135 of the secondary sealing angle 13 includes one or more studs 31. One end of the studs 31 opposite the secondary sealing angle 13 has a thread. A spacer 32 has fixing lugs 323 extending in alignment with the outer face of the spacer. A stud 31 is positioned between the fixing lugs 323 of two adjacent spacers 32.

As illustrated in FIG. 10f, a support plate 33 comprising an orifice is mounted on the stud 31. A nut 311 is mounted on the threaded end of the stud 31. The two adjacent spacers 32 are thus held in abutment by said plate bearing 33 against an inner face of the secondary sealing angle 13.

Alternatively, according to a variant not shown, the studs 31 extending from the secondary sealing angle 31 pass through holes in the primary sealing angle 913, the nut being mounted on the inner face of the angle primary sealing 913, the primary sealing angle 913 thus being held in abutment by said nut against the inner face of the spacer 32, the spacer 32 itself being held in abutment by said nut against an inner face of the angle secondary seal 13.

As illustrated in FIG. 11, the primary sealing angle 913 may alternatively comprise two planar branches forming between them an angle equal to the angle a between the bearing walls of the edge, that is to say 90 ° in the case illustrated by FIG. 11. The primary sealing angle 913 is then fixed on a support 37 forming an angle equal to the angle a. Such a support 37 can for example be a beam of isosceles triangular section, the base of the triangle being fixed on the external face of the spacer 32.

A similar angle structure can also be used in a re-entrant edge 201 of the tank. Figure 13 shows a tank edge between two tank walls forming an interior angle of the order of 90 °. Such a vessel edge has a corner structure 510 similar to the corner structure 10 as described with reference to FIGS. 2 to 6, with the difference that the first anchoring wing 11 extends parallel away from the load-bearing wall 5 of the first tank wall 1, and the second anchor wing 211 extends parallel away from the support wall 25 of the second tank wall 2.

With reference to FIG. 14, a cutaway view of an LNG or propane vessel 1070 shows a sealed and insulated vessel 1000 of general prismatic shape mounted in the double hull 1072 of the vessel. The wall of the tank comprises at least one waterproof barrier intended to be in contact with the liquefied gas contained in the tank and at least one insulating barrier arranged between the waterproof barrier and the double shell 1072.

In a manner known per se, loading / unloading lines 1073 arranged on the upper deck of the ship can be connected, by means of appropriate connectors, to a maritime or port terminal for transferring a cargo of liquefied gas from or to the tank 1000.

FIG. 14 represents an example of a maritime terminal comprising a loading and unloading station 1075, an underwater pipe 1076 and an onshore installation 1077. The loading and unloading station 1075 is a fixed offshore installation comprising a movable arm 1074 and a tower 1078 which supports the movable arm 1074. The movable arm 1074 carries a bundle of insulated flexible pipes 1079 which can be connected to the loading / unloading lines 1073. The movable arm 1074 can be adjusted to suit any size of LNG carrier. A connecting pipe, not shown, extends inside the tower 1078. The loading and unloading station 1075 allows the loading and unloading of the ship 1070 from or to the shore installation 1077. This includes liquefied gas storage tanks 1080 and connection pipes 1081 connected by the submarine pipe 1076 to the loading or unloading station 1075. The submarine pipe 1076 allows the transfer of liquefied gas between the loading or unloading station 1075 and the shore installation 1077 over a long distance, for example 5 km, which makes it possible to keep the ship 1070 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 1070 and / or pumps fitted to the shore installation 1077 and / or pumps fitted to the loading and unloading station 1075 are used.

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 are within the scope of the invention.

The use of the verb "behave", "understand" or "include" and its conjugate forms do not exclude the presence of other elements or steps than those set out in a claim. The use of the indefinite article "a" or "an" for an element or a stage does not exclude, unless otherwise stated, the presence of a plurality of such elements or stages.

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

Claims (15)

1. Watertight and thermally insulating tank (1000) for storing a fluid comprising a first wall (1) and a second wall (2), the first (1) and the second wall (2) each comprising, in a direction d thickness, a load-bearing wall (5, 25), a thermal insulation barrier (6, 26) fixed to the load-bearing wall (5, 25), a sealing membrane (7, 27) parallel to the load-bearing wall ( 5, 25) and fixed to the thermal insulation barrier (6, 26), the sealed and thermally insulating tank (1000) comprising, at an edge (100, 201) between the bearing wall (5) of the first wall ( 1) and the supporting wall (25) of the second wall (2), a corner structure (10), the corner structure comprising: - a first anchoring wing (11) fixed to the supporting wall (5) of the first wall (1), - a second anchoring wing (211) fixed to the load-bearing wall (25) of the second wall (2), - a sealing angle (13) fixed, on the one hand, to the first anchoring wing (11) by means of a first connecting piece (12), and on the other hand, to the second anchor wing (211) by means of a second connecting piece (212), the sealing angle (13) being connected in leaktight manner to the sealing membrane (27) of the first wall and to the sealing membrane (7) of the second wall, the sealing angle (13) comprising a first planar branch (131) extending in the plane of the sealing membrane (7) of the second wall (2 ), and a second planar branch (132) extending in the plane of the sealing membrane (27) of the first wall (1), the first connecting piece (12) comprising a first planar branch (122) parallel to the first anchoring wing (11), and a second planar branch (121) parallel to the waterproofing membrane (7) of the second wall (2), the second connecting piece (212) comprising a first planar branch (2122) parallel to the second anchoring wing (211), and a second planar branch (2121) parallel to the sealing membrane (27) of the first wall (1), the first planar branch (122) of the first connecting piece (12) being welded to the first anchoring wing (11), the first planar branch (2122 ) of the second connecting piece (212) being welded to the second anchoring wing (211), the first planar branch (131) of the sealing angle (13) being welded to the second planar branch (121) of the first connecting piece (12), and the second planar branch (132) of the sealing angle (13) being welded to the second planar branch (2121) of the second connecting piece (212), the membrane sealing (27) of the first wall (1) being welded to the second planar branch (132) of the a sealing angle (13), and the sealing membrane (7) of the second wall (2) being welded to the first planar branch (131) of the sealing angle (13). 2. Tank (1000) according to the preceding claim wherein the sealing angle (13) comprises a plurality of transverse sections (135), two adjacent transverse sections (135) being tightly connected to each other by by means of a corrugated connection (15) projecting towards the interior of the tank, the sealing membrane (27, 7) of the first and of the second wall each comprising a series of corrugations (71 , 271) projecting towards the interior of the tank and developing in a direction perpendicular to the edge (100, 201), each corrugation (71) of the first wall and of the second wall being aligned with a connector corrugated (15) of the sealing angle. 3. Tank (1000) according to claim 1 wherein the sealing angle (13) comprises a plurality of cross sections (135), two adjacent cross sections (135) being sealingly connected to each other by by means of a corrugated connection (15) projecting towards the interior of the tank, the sealing membrane (27, 7) of the first and of the second wall each comprising a series of corrugations (71 , 271) projecting towards the outside of the tank and developing in a direction perpendicular to the edge (100, 201), each corrugation (71) of the first wall and of the second wall being aligned with a connector corrugated (15) of the sealing angle. 4. Tank (1000) according to one of the preceding claims in which a corrugated connection (15) comprises a central part (153), a first bent end (151), and a second bent end (152), the first bent end (151) fitting, on the one hand, on a corrugation (71) of the sealing membrane (27) of the first wall, and on the other hand, on the central part (153), the second bent end (152) fitting, on the one hand, on a corrugation (71) of the sealing membrane (7) of the second wall, and on the other hand, on the central part (153). 5. Tank (1000) according to one of the preceding claims, in which the first anchoring wing (11) extends parallel to the bearing wall (5) of the first wall (1), the second anchoring wing (211) extending parallel to the support wall (25) of the second wall (2). 6. Tank (1000) according to one of the preceding claims wherein, at the edge (100), the carrier wall (5) of the first wall and the carrier wall (25) of the second wall together form a angle (a) projecting from the inside of the tank, the first anchoring wing (11) extending in the extension of the bearing wall (5) of the first wall (1), and the second anchoring wing ( 211) extending in the extension of the supporting wall (25) of the second wall (2). 7. Tank (1000) according to one of claims 1 to 5 wherein, at the edge (201), the carrier wall (5) of the first wall and the carrier wall (25) of the second wall form together an angle (a) returning from the inner side of the tank, the first anchoring wing (11) extending parallel to the bearing wall (5) from the first wall (1), the second anchoring wing (211) extending parallel to the distance from the supporting wall (25) of the second wall (2). 8. Tank (1000) according to one of the preceding claims wherein the thermally insulating barrier (6, 26) of the first wall (1) and / or the second wall (2) comprises a plurality of heat-insulating elements (61 ), each heat-insulating element (61) comprising a cover panel facing towards the inside of the tank, the internal face of the heat-insulating element 61 (61) bordering the edge (100) comprising a recess (62) facing opposite the waterproofing membrane (27), a connection plate (63) being housed in the recess (62) and flush with the interior face of the heat-insulating element (61) and the interior face of the planar branch (132) of the sealing angle (13) on which the sealing membrane (27) is fixed in order to form a continuous planar support surface for the sealing membrane (27). 9. Tank (1000) according to one of the preceding claims in which the thermal insulation barrier (6, 26) fixed to the load-bearing wall (5, 25) is a secondary thermal insulation barrier, the sealing membrane. (7, 27) fixed to the secondary thermal insulation barrier (6, 26) being a secondary waterproofing membrane, the sealing angle (13) connected in leaktight manner to the secondary waterproofing membrane (27) the first wall and the secondary sealing membrane (7) of the second wall being a secondary sealing angle, the first (1) and the second (2) wall further comprising, in the thickness direction of the tank, from outside to inside, over the secondary thermal insulation barrier (6,26) and the secondary sealing membrane (7, 27), a primary thermal insulation barrier (8, 28) and a primary sealing membrane (9, 29) of the designed to be in contact with the liquid contained in the tank, the angle structure (10) further comprising a primary sealing angle (913) connected in leaktight manner to the primary sealing membrane (9) of the first wall and the primary sealing membrane (29) of the second wall. 10. Tank (1000) according to claim 9 wherein the primary sealing angle (913) is fixed to the secondary sealing angle (13) by means of one or more spacers (32). 11. Tank (1000) according to claim 10 wherein an outer face of the primary sealing angle (913) carries primary studs (35), each spacer (32) comprising at least one orifice through which a primary stud (35 ), the spacer (32) being held in abutment against the external face of the primary sealing angle (913) by a primary nut mounted on the primary stud (35), an internal face of the secondary sealing angle ( 13) carrying secondary studs (31), a spacer (32) having fixing lugs (323), a secondary stud (31) being positioned between the fixing lugs (323) of two adjacent spacers (32), a plate bearing (33) having an orifice being mounted on the secondary stud (31), the two adjacent spacers (32) being held in abutment by said bearing plate (33) against an interior face of the secondary sealing angle (13) by é secondary nut (311) mounted on the secondary stud (31). 12. Tank (1000) according to one of claims 9 to 11 wherein the secondary sealing membranes (27, 7) are composite membranes, the secondary sealing angle (13) having a plurality of cross sections (135 ), two adjacent cross sections (135) being tightly connected to each other by means of a composite sealing strip. 13. Ship (1070) for transporting a cold liquid product, the ship comprising a hull (1072) and a tank (1000) according to one of claims 1 to 12 disposed in the hull. 14. A method of loading or unloading a ship (1070) according to claim 13, in which a cold liquid product is conveyed through insulated pipes (1073, 1079, 1076, 1081) from or to a floating storage installation or terrestrial (1077) to or from the vessel. 15. Transfer system for a cold liquid product, the system comprising a vessel (1070) according to claim 13, isolated pipes (1073, 1079, 1076, 1081) arranged so as to connect the tank (1071) installed in the hull of the ship at a floating or on-shore storage facility (1077) and a pump for driving a flow of cold liquid product through insulated pipelines from or to the floating or on-shore storage facility to or from the ship's tank.