KR20210058937A - Storage facilities for liquefied gas - Google Patents

Abstract

The present invention relates to a storage facility comprising a load-bearing structure and a tank, wherein the tank comprises at least a first tank wall and a second tank wall, each tank wall having at least one sealing membrane and at least one thermal insulation. Comprising a barrier, the facility comprises a connection structure (11), the connection structure (11) comprises a main beam (12) consisting of first and second panels (14), the connection structure (11) Also includes at least one first connection plate 19 attached to the first panel 13 and a second connection plate 20 attached to the second panel 14, wherein the load-bearing structure It comprises at least one first attachment flange 21 and at least one second attachment flange 22, the first connection plate 19 being attached to the first attachment flange 21 and the second connection plate ( 20) is attached to the second attachment flange 22.

Description

Storage facilities for liquefied gas

The present invention relates to the field of membrane type sealing and insulating tanks. The present invention provides, for example, tanks for transport of liquefied petroleum gas (LPG) at temperatures between -50° C. and 0° C. or liquefied natural gas (LNG) at about -162° C. at atmospheric pressure, especially at low temperatures. It relates to the field of sealed and insulated tanks for storage and/or transport of liquefied gases. These tanks can be installed on land or on floating structures. In the case of a floating structure, the tank may be intended to transport liquefied gas or to contain a liquefied gas serving as fuel for propulsion of the floating structure.

In one embodiment, the liquefied gas is LNG, ie a mixture with a high methane content stored at a temperature of approximately -162° C. at atmospheric pressure. Other liquefied gases, in particular ethane, propane, butane or ethylene may also be envisioned.

Patent document WO2013124556 describes a sealing and insulating tank in which an insulating barrier is formed of a plurality of juxtaposed insulating blocks. These insulating blocks include a lower plate, a lower structural insulating foam, an intermediate plate, an upper structural insulating foam and a cover plate successively in the thickness direction of the tank wall. In these insulating blocks, the plates are held at a distance from each other in the thickness direction of the tank wall by structural insulating foam.

When loading and unloading LNG, changes in temperature and the state of charge of the tank impose high stresses on the membranes of the tank. Likewise, the movement of the ship during marine transport exerts a high force on the barriers of the tank. In order to prevent deterioration of the sealing and thermal insulation properties of the tank, at least the secondary sealing membrane is fixed to the load-bearing structure with the aid of a connecting structure at the level of the corners between the transverse and longitudinal walls of the tank.

Fastening the connecting structures to the load-bearing structure on the one hand and to the sealing membranes on the other makes it possible to transfer forces between the membranes and the hull of the ship, thereby reinforcing the overall structure of the tank.

The connection structure makes it possible in particular to absorb the tensile forces due to the heat shrinkage of the metallic elements forming the sealing barriers, the deformation of the hull in the sea and the state of filling of the tanks.

Some aspects of the invention are that this type of insulating barrier assembled with this type of connection structure will cause thickness differences in the tank walls when the tank is subjected to high temperature changes, for example when loading liquefied gas into the tank. It comes from the observation that it can be. In practice, if the insulating barrier shrinks more than the connecting structure supporting the sealing membrane, the result is to move the sealing membrane away from the insulating barrier. Nowadays, the insulating barrier also has the function of supporting the sealing membrane. Thus, this type of difference tends to weaken the sealing membrane and increase the risk of damage.

In the remainder of the description, the offset between the insulating barrier and the sealing membrane during high temperature changes will be referred to as the barrier/membrane offset.

One idea behind the invention is to limit this offset.

According to one embodiment, the present invention provides a liquefied gas storage facility comprising a load-bearing structure and a sealing and insulating tank disposed within the load-bearing structure, wherein the tank comprises at least a first load of the load-bearing structure. -A first tank wall attached to a bearing wall and a second tank wall attached to a second load-bearing wall of the load-bearing structure, each tank wall having at least one sealing membrane and at least one insulating barrier Wherein the insulating barrier is disposed between the sealing membrane and the load-bearing structure, and the storage facility attaches the sealing membrane to the load-bearing structure along an edge between the first and second load-bearing walls. It includes a connection structure configured to allow,

The connection structure is parallel to the first load-bearing wall and is sealed to the second load-bearing wall and parallel to the first panel and the second load-bearing wall, which are attached in a sealing manner to the sealing membrane of the first tank wall. And a main beam consisting of a second panel attached to the membrane in a sealing manner, and the connection structure is also attached to the first panel and to the first panel in the direction of the second load-bearing wall. At least one first connection plate extending in parallel, and at least one second connection plate attached to the second panel and extending parallel to the second panel in the direction of the first load-bearing wall,

The load-bearing structure has at least one first attachment flange protruding from the second load-bearing wall parallel to the first tank wall at a distance from the edge, and the first load- At least one second attachment flange protruding from the supporting wall parallel to the second tank wall,

The first connection plate is attached to the first attachment flange, the second connection plate is attached to the second attachment flange,

The first assembly extending between the second load-bearing wall and the second panel of the main beam and including the first attachment flange and the first connecting plate is balanced when the tank is empty and filled from ambient temperature. It has substantially the same heat shrinkage as the heat shrinkage of the insulating barrier of the second tank wall when cooled to temperature, extends between the first load-bearing wall and the first panel of the main beam, the second attachment flange and the second The second assembly including the connection plate is the sealing membrane so that the tank has substantially the same heat shrink as the heat shrink of the insulating barrier of the first tank wall when the tank is cooled from an ambient temperature in an empty state to an equilibrium temperature in a filled state. and the main beam is 0.5x10 ^-6 to 7.5x10 ^-6 K ^-1 between is made of a metal alloy having a coefficient of thermal expansion (inclusive), the at least first and second mounting plates are thermal expansion coefficient 20x10 ^-6 to 60x10 ^-6 K ^-1 is made of a material between a (inclusive), the heat insulating barrier is made of a thermal expansion coefficient of 20x10 ^-6 to 60x10 ^-6 K ^-1 between a (inclusive) material.

The filled state corresponds to a state in which the tank is partially or completely filled.

Thanks to the above features, the connection structure has connection plates having a coefficient of expansion that is higher than the coefficient of expansion of the main beam and is about the same size as the coefficient of thermal expansion of the insulating barrier, which means that the connection structure and thus the sealing membrane are insulated. During thermal contraction of the barrier it is possible to follow the movement in the thickness direction. Thus, the construction of a load-bearing structure composed of different materials enables efficient management of the phenomenon of thickness change of the tank walls of the sealing and insulating tank after a high temperature change to prevent too high membrane/barrier offset.

Embodiments of the above type of storage facility have one or more of the following features.

According to one embodiment, the attachment between the first connection plate and the first attachment flange and/or the attachment between the second connection plate and the second attachment flange may be performed by welding, bonding, rivets or bolts.

According to an embodiment, the attachment between the first connection plate and the first panel and/or the attachment between the second connection plate and the second panel may be performed by welding, bonding, rivets or bolts.

According to one embodiment, the first panel is welded to the sealing membrane of the first wall in a sealing manner, ie with a continuous welding bead between the two elements.

According to one embodiment, the second panel is welded to the sealing membrane of the first tank wall in a sealing manner, ie with a continuous welding bead between the two elements.

Thus, the connection structure provides continuity of the sealing membrane in the region of the intersection between the first tank wall and the second tank wall.

According to one embodiment, the sealing membrane is made of an iron and nickel alloy having a coefficient of thermal expansion between ^{0.5x10 -6} and 2x10 ^-6 K ^{-1 (including a boundary value).}

According to one embodiment, the sealing membrane is 6.5x10 ^-6 to 7.5x10 ^-6 K ^-1 iron and manganese, with a thermal expansion coefficient between the (inclusive), for example, with manganese of 19 to 22% by weight It is made of an alloy.

According to one embodiment, the connection structure is attached to the first panel and includes a plurality of first connection plates regularly or irregularly spaced apart from each other along the edge, the connection structure is attached to the second panel, And a plurality of second connecting plates regularly or irregularly spaced from each other along the edge.

Thanks to these features, the attachment between the sealing membrane and the load-bearing structure is carried out in a discontinuous manner by means of connecting plates spaced apart from each other. This separate attachment makes it possible to prevent unwanted bending between these various elements and thus avoid damage.

According to one embodiment, the first and second attachment flanges are made of stainless steel having a ^{coefficient of thermal expansion between 12x10 -6} and 16x10 ^-6 K ^{-1 (including threshold).}

According to one embodiment, the insulating barrier is made of a fiber-reinforced foam having a ^{coefficient of thermal expansion between 35x10 -6} and 60x10 ^-6 K ^{-1 (including a boundary value).}

According to one embodiment, the foam is a polyurethane foam.

According to one embodiment, the insulating barriers of the first tank wall and the second tank wall are each made of fiber reinforced foam, the fibers being oriented parallel to the first load-bearing wall and the second load-bearing wall, respectively.

According to an embodiment, the first and second connection plates are ^{iron-nickel having a coefficient of thermal expansion between 25x10 -6} to 30x10 ^-6 K ^-1 (including a boundary value), for example iron-nickel-manganese or iron. -Made of nickel-chromium metal alloy.

According to one embodiment, the first and second connection plates are of aluminum having a thermal expansion coefficient between 20x10 ^-6 to 30x10 ^-6 K ^-1 (inclusive) made of a zinc alloy metal.

According to an embodiment, the first and second connecting plates have ^{a high content of manganese having a coefficient of thermal expansion between 20x10 -6} to 30x10 ^-6 K ^-1 (including a boundary value), for example, at least 50% It is made of an alloy with manganese.

According to one embodiment, the first and second connecting plates are made of a polymer material, possibly a fiber reinforced polymer material, with a coefficient of thermal expansion between ^{20x10 -6} and 60x10 ^-6 K ^{-1 (inclusive).}

According to one embodiment, the insulating barrier has a dimension of between 250 and 800 mm (including a boundary value) in the thickness direction of the tank wall.

According to an embodiment, the first and second connection plates are of a dimension greater than 150 mm in the thickness direction of the tank wall, preferably between 200 and 500 mm (including a boundary value), more preferably 300 to 400 mm. Have.

Thanks to the above features, the first and second connecting plates are dimensioned sufficient to ensure that the heat shrinkages of the first assembly and the second assembly are substantially equal to the heat shrinkage of the insulating barrier.

According to one embodiment, the first and second attachment flanges have a dimension of greater than 30 mm, preferably between 40 and 80 mm (including threshold) in the thickness direction of the sealing tank.

Thanks to the above features, the first and second attachment flanges are sufficient to enable the attachment of the first and second attachment flanges to the first and second connection plates, for example welding with the help of a welding torch. Have dimensions.

According to an embodiment, the first connecting plate is attached to the first panel between the primary insulating barrier of the first wall and the secondary insulating barrier of the first wall, and the second connecting plate is It is attached to the second panel between the primary insulating barrier and the secondary insulating barrier of the second wall.

According to an embodiment, the first connection plate includes a first end, a second end, and a central portion between the first and second ends, the first end being attached to the first attachment flange, and the The second end is attached to the first panel, the cross section of the center is different from the cross section of the first and second ends, and the cross section of the center is preferably smaller than the cross section of the first and second ends.

According to an embodiment, the second connection plate includes a first end, a second end, and a central portion between the first and second ends, the first end being attached to the second attachment flange, and the The second end is attached to the second panel, the cross section of the center is different from the cross section of the first and second ends, and the cross section of the center is preferably smaller than the cross section of the first and second ends.

Thus, the difference in cross-section between the center and the ends makes it possible to reduce the flow of heat between the secondary insulating barrier and the load-bearing wall and to increase the mechanical fatigue strength.

According to one embodiment, the first panel includes a first anchor portion extending between the second load-bearing wall and the sealing membrane of the second wall, and the second panel comprises the first A second fixing portion extending between the load-bearing wall and the sealing membrane of the first wall, the first connection plate is attached to the first fixing portion, and the second connection plate is the second fixing portion Is attached to.

According to an embodiment, the first panel portion and the second panel portion have a dimension greater than 30 mm, preferably between 40 and 80 mm, in the thickness direction of the sealing and insulating tank.

Thanks to the above features, the first panel portion and the second panel portion are welded to the first and second panel portions with the help of a welding torch on each of the first and second connection plates. It has a specific dimension that makes it possible.

According to an embodiment, the first panel portion and the second panel portion are a first panel fixing portion and a second panel fixing portion, respectively, and the first panel accommodates a first panel attached to the sealing membrane of the first wall. A portion, and the second panel includes a second panel receiving portion attached to the sealing membrane of the second wall.

According to an embodiment, the first panel and the second panel are attached at right angles to each other by a welding connection, and the first panel accommodating portion and the first panel fixing portion are respectively located on both sides of the welding connection, and accommodating the second panel The part and the second panel fixing part are respectively located on both sides of the welding connection part.

According to an embodiment, the insulating barrier is a secondary insulating barrier and the sealing membrane is a secondary sealing membrane, and the first tank wall and the second tank wall are in a thickness direction from the outside to the inside of the tank, the secondary insulating barrier , The secondary sealing membrane, a primary insulating barrier supported by the secondary sealing membrane, and a primary sealing membrane supported by the primary insulating barrier.

According to an embodiment, the secondary insulating barrier includes a plurality of parallel parallelepiped insulating blocks, the secondary sealing membrane includes a plurality of parallel strkes, and the strake is an insulating panel of the secondary insulating barrier. A planar center placed on the upper surface of the wires and two raised edges protruding toward the primary sealing membrane compared to the center, and the strakes are juxtaposed according to a repeating pattern and welded together in a sealing manner at the level of the raised edges. And fixing flanges fixed to the insulating blocks of the secondary insulating barrier are disposed between the juxtaposed strakes to hold the secondary sealing membrane on the secondary insulating barrier.

According to one embodiment, the primary sealing membrane is corrugated metal plates.

According to one embodiment, the present invention provides a method of manufacturing a liquefied gas storage facility comprising a load-bearing structure and a sealing and insulating tank disposed within the load-bearing structure, wherein the tank comprises at least the load-bearing structure A first tank wall attached to the first load-bearing wall of the load-bearing structure and a second tank wall attached to the second load-bearing wall of the load-bearing structure, each tank wall having at least one sealing membrane and at least An insulating barrier, wherein the insulating barrier is disposed between the sealing membrane and the load-bearing structure, the storage facility load-bearing the sealing membrane along an edge between the first and second load-bearing walls. It includes a connection structure configured to be attached to the support structure,

The connection structure is parallel to the first load-bearing wall and is sealed to the second load-bearing wall and parallel to the first panel and the second load-bearing wall, which are attached in a sealing manner to the sealing membrane of the first tank wall. And a main beam consisting of a second panel attached to the membrane in a sealing manner, and the connection structure is also attached to the first panel and to the first panel in the direction of the second load-bearing wall. At least one first connection plate extending in parallel, and at least one second connection plate attached to the second panel and extending parallel to the second panel in the direction of the first load-bearing wall,

The load-bearing structure has at least one first attachment flange protruding from the second load-bearing wall parallel to the first tank wall at a distance from the edge, and the first load- At least one second attachment flange protruding from the supporting wall parallel to the second tank wall,

The first connection plate is attached to the first attachment flange, the second connection plate is attached to the second attachment flange,

The sealing membrane and the main beam is made of a metal alloy having a thermal expansion coefficient between 0.5x10 ^-6 to 7.5x10 ^-6 K ^-1 (inclusive),

The method is:

-Selecting a material of at least the first and second attachment plates having a coefficient of thermal expansion between ^{20x10 -6} and 60x10 ^-6 K ^{-1 (including a boundary value),}

-Selecting a material of the insulating barrier having a coefficient of thermal expansion between ^{20x10 -6} to 60x10 ^-6 K ^{-1 (including a boundary value),}

The first assembly extending between the second load-bearing wall and the second panel of the main beam and including the first attachment flange and the first connecting plate is balanced when the tank is empty and filled from ambient temperature. It has substantially the same heat shrinkage as the heat shrinkage of the insulating barrier of the second tank wall when cooled to temperature, extends between the first load-bearing wall and the first panel of the main beam, the second attachment flange and the second The second assembly comprising the connection plate, the selection step so that when the tank is cooled from an ambient temperature in an empty state to an equilibrium temperature in a filled state, the second assembly has substantially the same heat contraction as that of the insulating barrier of the first tank wall. Are executed.

According to one embodiment, the method comprises selecting a dimension of the insulating barrier in the thickness direction of the sealing and insulating tank, for example between 250 and 500 mm.

According to one embodiment, the method comprises selecting a dimension of the first and second connecting plates in the thickness direction of the sealing and insulating tank, for example to a value greater than 150 mm.

According to one embodiment, the method comprises selecting a dimension of the first and second attachment flanges in the thickness direction of the sealing and insulating tank, for example to a value greater than 50 mm.

According to one embodiment, the method comprises selecting dimensions of the first panel portion and the second panel portion in the thickness direction of the sealing and insulating tank, for example to a value greater than 50 mm.

Storage facilities of the above type are, for example, onshore storage facilities, for storing LNG, or offshore or oceanic, in particular methane carriers, floating storage and regasification units (FSRU), floating production storage and unloading (FPSO) units, It may be a floating storage facility such as. This type of storage facility may serve as a fuel tank in any type of ship.

According to one embodiment, a ship for transporting low-temperature liquid products comprises a double hull and a storage facility as mentioned above, the portion of the double hull forming the load-bearing structure of the storage facility.

According to one embodiment, the present invention provides a method of loading or unloading a vessel of the above type, wherein the low-temperature liquid product is floated from the floating or onshore storage facility to the tank of the vessel or from the tank of the vessel through insulated pipes or Transported to onshore storage facilities.

According to one embodiment, the present invention also provides a conveying system for a low-temperature liquid product, the system comprising the above-described ship, an insulated pipe arranged in a manner that connects the tank installed in the hull of the ship to a floating or onshore storage facility. And a pump for driving the flow of a low-temperature liquid product from the floating or onshore storage facility to the tank of the ship or from the tank of the ship to the floating or onshore storage facility through the insulating pipes.

The invention will be better understood during the following description with reference to the accompanying drawings of specific embodiments of the invention provided solely as a non-limiting illustration, and other objects, details, features and advantages of the invention. Will become clearer.
1 is a cross-sectional view of the tank at the level of the corner formed by two tank walls.
-Figure 2 is a schematic perspective view of the tank of Figure 1 showing only the connection structure and the load-bearing structure.
-FIG. 3 is a graph showing the coefficient of thermal expansion that a connecting plate can have according to an acceptable membrane/barrier offset for a number of insulating barrier embodiments.
4 is a graph showing the coefficient of thermal expansion that the connecting plate can have according to the coefficient of thermal expansion of the insulating barrier for a plurality of values of the membrane/barrier offset.
-Figure 5 is a schematic cut-away view of a methane transport ship including a sealed and insulated tank and a terminal for loading/unloading the tank.

The tank wall is attached to the load-bearing wall of the load-bearing structure. By convention, no matter what the orientation of the tank wall relative to the Earth's gravitational field, "on" or "above" refers to a position that lies closer to the interior of the tank, and "under or below". Denotes the position that lies closer to the load-bearing structure.

1 shows a multi-layered structure of two tank walls 1, 101 of a sealed and insulated tank for storage of liquefied gas, for example liquefied natural gas (LNG). Each tank wall (1, 101) is, in the thickness direction, from the outside to the inside of the tank, a secondary insulating barrier (2, 102) held on the load-bearing walls (3, 103), the secondary insulating barrier (2). , A secondary sealing membrane (4, 104) leaning against the secondary sealing membrane (4, 104), a primary insulating barrier (5, 105) leaning against the secondary sealing membrane (4, 104), a primary sealing membrane intended to contact the liquefied gas contained in the tank ( 6, 106) are included in succession.

The load-bearing structure can in particular be formed by the hull or double hull of a ship. The load-bearing structure comprises a plurality of load-bearing walls (3, 103) forming the general shape of the tank, usually a polyhedral shape. The two load-bearing walls 3 and 103 are connected at the edge 100 to form a dihedral angle, which can have various values. Here, a value of 90° is displayed.

The secondary insulating barrier 2, 102 comprises a plurality of secondary insulating panels 7, 107 fixed to the load-bearing wall 3, 103 by means of holding devices (not shown) known per se.

The secondary insulating panels 7 and 107 comprise, for example, a lower plate made of plywood, a cover plate and, if applicable, an intermediate plate. In addition, the secondary insulating panels 7 and 107 comprise one or more layers of insulating polymer foam sandwiched between and adhered to a lower plate, a cover plate and, if applicable, an intermediate plate. The insulating polymer foam may in particular be a polyurethane-based foam, optionally reinforced by fibers.

The secondary sealing membrane 4, 104 comprises a continuous layer of metal strakes with raised edges. The strakes are welded to parallel welding supports fixed in grooves formed in the cover plates of the secondary insulating panels 7 and 107 by their raised edges. Strkes are made, for example, of Invar®: ie an alloy of iron and nickel with a coefficient of thermal expansion ^{generally between 1.2x10 -6} and 2x10 ^-6 K ^{-1 (inclusive).} It is also possible to use alloys of iron and manganese with a coefficient of thermal expansion of approximately 7x10 ^-6 K ^{-1 in general.}

The primary insulating barrier (5, 105) comprises a plurality of primary insulating panels (8, 108), which can be manufactured according to various structures known per se.

The primary sealing membranes 6 and 106 can be manufactured in a variety of ways. In Figure 1, the primary sealing membrane comprises a continuous layer of sheet metal characterized by two series of mutually orthogonal corrugations. The first series of corrugations 9 and 109 extend at right angles to the edge 100. The second series of corrugations 10 and 110 extend parallel to the edge 100. The two series of corrugations may have regular spacing or periodically irregular spacing.

Now with reference to FIGS. 1 and 2 the structure of the secondary element of the tank at the level of the connection point between the two tank walls 1, 101 will be described in more detail.

The secondary sealing membrane (4) of the first tank wall (1) and the secondary sealing membrane (104) of the second tank wall (101) are at the level of the corner of the tank, i.e. two load-bearing walls (3, 103). ) Is fixed to the load-bearing structure with the help of the connection structure 11 near the edge 100 to which it is connected.

The connection structure 11 includes a metal main beam 12 disposed parallel to the edge 100. The main beam 12 comprises a first panel 13 extending parallel to the load-bearing wall 3 and a second panel 14 extending parallel to the load-bearing wall 103. These two panels 13, 14 are assembled at an angle formed between the two load-bearing walls 3, 103 by welding connection, ie an angle corresponding to a right angle here. For example, the second panel 14 may be formed of two plates welded to each of the opposite sides of the first panel 13, and these are manufactured integrally or a plurality of plates welded to each other. They can be manufactured in the same way. Thus, the main beam 12 has a cross shape.

The portion of the first panel 13 that extends between the load-bearing structure and the welded connection of the panels 13, 14 has a connection structure 11 to absorb the tensile force in the secondary sealing membrane 4 It is an anchor portion 15 capable of being connected to the load-bearing wall 103. Likewise, the portion of the second panel 14 extending between the load-bearing structure and the welded connection of the panels 13, 14 is the connecting structure 11 to absorb the tensile force in the secondary sealing membrane 104. ) To the load-bearing wall (3).

The portion of the first panel 13 extending beyond the welded connection of the two panels 13, 14 and between the secondary insulating barrier 2 and the primary insulating barrier 5 has an edge of the secondary sealing membrane 4 It is a receiving portion 17 to be welded. Similarly, the portion of the second panel 14 extending beyond the welded connection of the two panels 13 and 14 and between the secondary insulating barrier 102 and the primary insulating barrier 105 is It is the receiving part 18 to which the edge is welded.

The connection structure 11 is also attached to the fixing portion 15 of the first panel 13 and at least one first connection extending parallel to the first panel 13 in the direction of the load-bearing wall 103 Includes plate 19. Likewise, the connection structure 11 is attached to the fixing portion 16 of the second panel 14 and extends parallel to the second panel 14 in the direction of the load-bearing wall 3. It includes a connection plate (20).

The load-bearing structure has a first attachment flange (21) protruding parallel to the tank wall (1) from the load-bearing wall (103) at a distance from the edge (100), and a load at a distance from the edge (100). -Comprising a first attachment flange 22 protruding parallel to the tank wall 101 from the bearing wall 3.

The first connection plate 19 is attached to the first attachment flange 21 in a manner that connects the fixing portion 15 of the first panel 13 to the load-bearing wall 103. Likewise, the second connection plate 20 is attached to the second attachment flange 22 in a way that connects the fixing part of the second panel to the load-bearing wall 3. In this way, the secondary sealing membranes 4 and 104 are fixed to the load-bearing structure through the intermediation of the connection structure 11.

The attachment between the connection structure and the load-bearing walls 3, 103 can be made in a separate manner. The fixing portion 15 of the first panel 13 is attached to the first attachment flange 21 by a plurality of first connecting plates 19 regularly spaced apart from each other along the edge 100. Similarly, the fixing portion 16 of the second panel 14 is attached to the second attachment flange 22 by a plurality of second connecting plates 20 regularly spaced from each other along the edge 100. .

2 shows in perspective view an attachment according to another embodiment between the connection structure and the load-bearing walls 3, 103. As in the embodiment of FIG. 1 and as shown in FIG. 2, the attachment between the connection structure and the load-bearing walls 3, 103 is carried out in a separate manner. The first panel 13 is attached to the first attachment flange 21 by a plurality of first connecting plates 19 regularly spaced from each other along the edge 100. Likewise, the second panel 14 is attached to the second attachment flange 22 by a plurality of second connecting plates 20 regularly spaced from each other along the edge 100.

Moreover, in this embodiment, the second panel 14 is formed of only one plate and the first panel 13 is formed of only one plate, as a result of which the first panel 13 and the second The panels 14 are either welded to each other by one of their edges, or are manufactured by bending at an angle equal to the angle between the first load-bearing wall 3 and the second load-bearing wall 103. Thus, the first panel 13 and the second panel 14 only extend between the secondary insulating barriers 2 and 102 and the primary insulating barriers 5 and 105. Accordingly, here the connecting plates 19 and 20 are fixed to the main beam 12 between the secondary insulating barriers 2 and 102 and the primary insulating barriers 5 and 105. Thus, in the illustrated example, the main beam 12 is L-shaped.

Additionally, the first connection plates 19 and the second connection plates 20 may alternate along the edge 100 as shown in FIG. 2. The connection plates 19 and 20 may be equally attached to the first panel 13 and the second panel 14 at the same level of the edge 100.

The first connecting plates 19 and the second connecting plates 20 have a first end, a first panel 13 and a first end welded to the first attachment flange 21 and the second attachment flange 22, respectively. It includes a second end welded to the two panels, respectively, and a central portion between the first end and the second end. Thus, the central portion may have a cross-section different from the cross-sections at the welded ends, for example, the central portion is smaller than the cross-section at the ends. This advantageously makes it possible to reduce the flow of heat between the secondary barriers 104, 4 and the load-bearing walls 3, 102 and improve the mechanical fatigue strength.

In an embodiment not shown, the attachment between the connection structure 11 and the load-bearing walls 3, 103 is carried out in a continuous manner. In fact, the fixing portion 15 of the first panel 13 is terminated by a single first connecting plate 19 having a size equal to the size of the first attachment flange 21 or along the edge 100. It is fixed to the first attachment flange 21 by a plurality of first connection plates 19 arranged at the end of and in succession. Similarly, the fixing portion 16 of the second panel 14 is terminated by a single second connecting plate 20 having a size equal to the size of the second attachment flange 22 or along the edge 100. It is fixed to the second attachment flange 22 by a plurality of second connection plates 20 arranged at the end of and in succession.

Now, methods are described which enable the selection of available materials for manufacturing the connection structure 11 to limit the barrier/membrane offset. To this end, the material of the connecting plates 19 and 20 is such that the connecting plate 11 and the secondary insulating barrier 2 and 102 contact in substantially the same manner depending on the material of the secondary insulating barrier 2 and 102. Can be chosen in any way.

In the following examples, the dimensions and materials of the connection structure 11, the secondary insulating barriers 2 and 102 and the attachment flanges 21 and 22 are determined as follows.

-Dimensions in the thickness direction of the secondary insulating barriers (2, 102): 400 mm.

-Dimensions in the thickness direction of the attachment flanges (21, 22): 50mm.

-Dimensions in the thickness direction of the fixing portions 15 and 16 of the first and second panels 13 and 14: 50 mm.

-Material of main beam 12: Invar® with a coefficient of thermal expansion of ^{1.2x10 -6} K ^-1.

-Material of attachment flanges (21, 22): steel with a coefficient of thermal expansion of ^{15x10 -6} K ^-1

The thermal gradient in the materials used is equally assumed to be substantially linear. It is assumed that the change in temperature between the secondary sealing membranes 4 and 104 and the load-bearing walls 3 and 103 is equal to 130 K.

3 shows a graph in which the barrier/membrane offset is expressed in mm on the abscissa and the coefficient of thermal expansion that the material of the connecting plates can have in the ordinate ^{is expressed as K -1.} A number of curves 23 to 28 for different types of secondary insulating barriers 2 and 102 are shown.

Curve 23 can have the connecting plates 19, 20 depending on the barrier/membrane offset for the secondary insulating barrier 2, 102 made of plywood box sections with a coefficient of thermal expansion of approximately 6x10 ^-6 K ^-1. Indicates the coefficient of thermal expansion. Moreover, line 34 represents the coefficient of thermal expansion of the material Invar®. Thus, the intersection between line 34 and curve 23 represents a combination of connecting plates 19, 20 made of Invar® and secondary insulating barriers 2, 102 made of plywood.

Thus, as can be seen in Figure 3, the plywood/Invar® combination has a barrier/membrane offset less than 0.1, and this value lies within the acceptable range.

It is noted that it is desirable to limit the barrier/membrane offset to a value between 0 and 1 mm, more preferably between 0 and 0.8 mm in order to prevent damage to the secondary sealing membranes 4 and 104. In fact, if it exceeds 1 mm, the secondary sealing membrane 4, 104 undergoes a so-called "step" effect in which the secondary sealing membrane is no longer sufficiently supported by the secondary insulating barriers 2, 102 and has a high bending force ( bending force). Moreover, the negative barrier/membrane offset, i.e. in the case where the connecting structure 11 shrinks more than the secondary insulating barriers 2, 102, the secondary sealing membranes 4, 104 are preferred for the secondary insulating barriers 2, 102. It may result in the application of a compressive force that is not. Therefore, the ideal value of the barrier/membrane offset is a positive value and is closest to 0 mm. However, the material chosen for the connecting plates 19, 20 must be able to withstand the forces experienced by the secondary sealing membrane 4, 105 evenly so that its ends are, in particular, in pulling/compression at relatively low temperature values. , It must be strong enough.

Curves 24, 25, 26, 27 and 28 represent the coefficient of thermal expansion that the connecting plates 19 and 20 can have depending on the barrier/membrane offset.

Secondary, for example made of insulating foam, with a coefficient of thermal expansion of ^{20x10 -6} K ^-1 , 30x10 ^-6 K ^-1 , 40x10 ^-6 K ^-1 , 50x10 ^-6 K ^-1 , and 6x10 ^-6 K ^{-1 respectively} It shows the coefficient of thermal expansion that the connecting plates 19 and 20 can have according to the barrier/membrane offset for the insulating barriers 2 and 102.

In these examples, from the curve, the material Invar® for the connection plates 19 and 20 is thermal expansion coefficient of 20x10 ^-6 K ^-1 to 60x10 ^-6 K ^-1 for the insulation between the foam (inclusive) You can see that it's not the best fit. In practice, the allowable offset is even greater than 0.8 mm for coefficients of thermal expansion values greater than ^{40x10 -6} K ^-1.

For example, in the case of a polyurethane foam reinforced with fibers oriented in a direction perpendicular to the thickness direction and having a coefficient of thermal expansion of 50x10 ^-6 K ^-1 , in order to obtain a barrier/membrane offset of 0.8 mm, on the curve 27 Point 30 shows that the material of the connecting plates 19 and 20 should have a coefficient of thermal expansion ^{of approximately 25x10 -6} K ^-1. Moreover, in order to keep the barrier/membrane offset within the acceptable range between 0 and 0.8 mm, the coefficient of thermal expansion of the connecting plates 19, 20 should be between ^{approximately 25x10 -6} K ^-1 to 65x10 ^-6 K ^-1. do.

The curves in FIG. 3 show how to select the available material for the connecting plates 19 and 20. The person skilled in the art will know how to determine similar curves under different hypotheses, for example at different thicknesses of the insulating barrier.

In practice, the following equation makes it possible to determine the coefficient of thermal expansion of the connecting plates 19 and 20 according to these various parameters.

here,

α _p is the coefficient of thermal expansion of the connecting plates 19, 20,

Lp is the dimension of the connecting plates 19, 20 in the thickness direction of the tank wall,

Li is the dimension of the fixing parts 15 and 16 in the thickness direction,

La is the dimension in the thickness direction of the attachment flanges 21, 22,

α _m is the coefficient of thermal expansion of the secondary insulating barrier (2, 102),

ΔTmax is the temperature change between the secondary sealing membrane (4, 104) and the load-bearing wall (3, 103),

Ead is the allowed barrier/membrane offset.

FIG. 4 shows, under the same hypotheses as used in FIG. 3, the coefficient of thermal expansion of the secondary insulating barriers 2 and 102 on the ^{abscissa axis as K -1} and the connection plates 19 and 20 on the ordinate axis. A graph in which the coefficient of thermal expansion of the material ^{is expressed as K -1 is shown.} A number of curves are shown for different values of barrier/membrane offset.

Curves 31, 32 and 33 can have the connecting plates 19, 20 according to the coefficient of thermal expansion of the secondary insulating barriers 2, 102 for each of the barrier/membrane offsets 0.1 mm, 0.8 mm and 1.2 mm. Indicates the coefficient of thermal expansion.

The table below shows examples A, B, C of different choices indicated by dots A, B and C in Figure 3, wherein the material of the secondary insulating barrier combined with the material of the connecting plate has barrier/membrane offsets within the acceptable range. So that it can be obtained.

Yes Secondary insulating barrier Connecting plate Barrier/membrane offset
A Perpendicular to the thickness
Fiber-reinforced PU foam
α=50 10 ^-6 K ^-1 15 to 25% by weight of Ni and
Fe/Ni alloy with some weight% Mn
α=30 10 ^-6 K ^-1
0.7mm B PU foam
α=60 10 ^-6 K ^-1 Polyetherimide resin
α=56 10 ^-6 K ^-1 0.5mm
C Fiber-reinforced PU foam inside the thickness of the tank wall
α=30 10 ^-6 K ^-1 15 to 25% by weight of Ni and
Fe/Ni alloy with some weight% Cr
α=25 10 ^-6 K ^-1
0.3mm

Example of selection of materials for secondary insulating barriers and connecting plates

Referring to FIG. 10, a cut-away view of the methane transport ship 70 shows the sealing and insulating tank 71 of the overall shape of the prism mounted in the double hull 72 of the ship. The walls of the tank 71 include a primary sealing barrier intended to contact the LNG contained in the tank, a secondary sealing barrier disposed between the primary sealing barrier and the double hull of the ship, and the primary sealing barrier and the secondary sealing barrier. And two insulating barriers respectively disposed between and between the secondary sealing barrier and the double hull 72.

In a manner known per se, loading/offloading pipes 73 arranged on the upper deck of the ship for transporting LNG cargo from or to the tank 71 The silver is connected to the terminal of the marine or port by means of suitable connectors.

10 shows an example of a marine terminal comprising a loading and/or unloading station 75, an underwater pipe 76 and an onshore facility 77. The loading and/or unloading station 75 is a fixed offshore installation comprising a mobile arm 74 and a tower 78 supporting the mobile arm 74. The movable arm 74 supports a bundle of insulating flexible tubes 79 that can be connected to the loading/unloading pipes 73. The directional movable arm 74 is adapted to all methane tanker loading gauges. A connection pipe, not shown, extends into the tower 78. The loading and/or unloading station 75 enables loading and unloading of the methane carrier 70 from or to the onshore facility 77. The onshore facility 77 includes liquefied gas tanks 80 and connecting pipes 81, the connecting pipes 81 being the loading and/or unloading station 75 through the underwater pipe 76. ). The underwater pipe 76 allows the transfer of liquefied gas between the loading or unloading station 75 and the onshore facility 77 over a long distance, e. (70) is allowed to remain a long distance from the coast

In order to generate the pressure required for the transfer of the liquefied gas, pumps mounted on the vessel 70 and/or pumps equipped at the loading and unloading station 75 are used.

Although the present invention has been described in terms of a number of specific embodiments, this is by no means intended to limit the present invention, and all technical equivalents and combinations of the described means, provided they fall within the scope of the invention as defined by the claims. It is clear to cover them.

The use of the verb "include or comprise" and its conjugations does not exclude the presence of elements or steps other than those recited in a claim.

In the claims, any reference signs between parentheses should not be construed as a limitation of the claim.

Claims (16)

A liquefied gas storage facility comprising a load-bearing structure and a sealed and insulating tank disposed within the load-bearing structure,
The tank 71 is attached to at least a first tank wall (1) attached to the first load-bearing wall (3) of the load-bearing structure and a second load-bearing wall (103) of the load-bearing structure. A second tank wall (101), each tank wall (1, 101) comprising at least one sealing membrane (4, 104) and at least one insulating barrier (2, 102), the insulating barrier (2, 102) is arranged between the sealing membrane (4, 104) and the load-bearing structure, the storage facility having an edge (100) between the first and second load-bearing walls (3, 103). Thus, it comprises a connection structure 11 configured to attach the sealing membranes 4, 104 to a load-bearing structure,
The connection structure 11 includes a first panel 13 parallel to the first load-bearing wall 3 and attached in a sealing manner to the sealing membranes 4 and 104 of the first tank wall 1 A main beam consisting of a second panel 14 parallel to the second load-bearing wall 103 and attached in a sealing manner to the sealing membranes 4 and 104 of the second tank wall 101 ( 12), wherein the connection structure 11 is also attached to the first panel 13 and extending parallel to the first panel 13 in the direction of the second load-bearing wall 103 At least one first connecting plate 19 and at least one attached to the second panel 14 and extending parallel to the second panel 14 in the direction of the first load-bearing wall 3 It includes a second connection plate 20,
The load-bearing structure comprises at least one first attachment flange (21) protruding parallel to the first tank wall (1) from the second load-bearing wall (103) at a distance from the edge (100) and , At least one second attachment flange (22) protruding parallel to the second tank wall from the first load-bearing wall at a distance from the edge (100),
The first connection plate 19 is attached to the first attachment flange 21, the second connection plate 20 is attached to the second attachment flange 22,
A first assembly extending between the second load-bearing wall and the second panel 14 of the main beam 12 and comprising the first attachment flange 21 and the first connecting plate 19 is the tank When (71) is cooled from the ambient temperature in the empty state to the equilibrium temperature in the filled state, it has substantially the same heat contraction as that of the heat insulation barrier 102 of the second tank wall 101, and the first load-bearing A second assembly extending between the wall (3) and the first panel (13) of the main beam (12) and comprising the second attachment flange (22) and a second connecting plate (20) is the tank (71) The sealing membranes (4, 104) so that the sealing membrane (4, 104) has substantially the same heat shrinkage as that of the insulating barrier (2) of the first tank wall (1) when cooled from the ambient temperature in the empty state to the equilibrium temperature in the filled state. and the main beam (12) is 0.5x10 ^-6 to 7.5x10 ^-6 K ^-1 between is made of a metal alloy having a coefficient of thermal expansion (inclusive), at least a first and a second mounting plate are thermal expansion coefficient of 20x10 ^{- 6} to 60x10 ^-6 K ^-1 is made of a material between (inclusive), the heat insulating barrier has a thermal expansion coefficient of 20x10 ^-6 to 60x10 ^-6 K ^-1 between is made of a material (inclusive), liquid Gas storage facility. The method of claim 1,
The connection structure 11 is attached to the first panel 13 and includes a plurality of first connection plates 19 regularly spaced apart from each other along the edge 100, and the connection structure 11 Liquefied gas storage facility, comprising a plurality of second connecting plates (20) attached to the second panel (14) and regularly spaced from each other along the edge (100). The method according to claim 1 or 2,
The first and second attachment flanges (21, 22) are made of stainless steel having a ^{coefficient of thermal expansion between 12x10 -6 and 16x10 -6} K ^-1 (including threshold). The method according to any one of claims 1 to 3,
The insulating barriers (19, 20) are ^{made of fiber-reinforced foam having a coefficient of thermal expansion between 35x10 -6} to 60x10 ^-6 K ^-1 (including boundary value), a liquefied gas storage facility. The method according to any one of claims 1 to 4,
The first and second attachment plates (19, 20) are made of an iron-nickel metal alloy having a coefficient of thermal expansion between ^{25x10 -6} to 30x10 ^-6 K ^{-1 (including threshold).} The method according to any one of claims 1 to 4,
The first and second connecting plates (19, 20) are made of a polymer material having a coefficient of thermal expansion between ^{40x10 -6} and 60x10 ^-6 K ^{-1 (including threshold).} The method according to any one of claims 1 to 6,
The insulating barrier (2, 102) has a dimension of between 250 to 800 mm (including a threshold value) in the thickness direction of the sealing and insulating tank, liquefied gas storage facility. The method according to any one of claims 1 to 7,
The first and second connection plates (19, 20) have a dimension greater than 150 mm in the thickness direction of the sealing and insulating tank, liquefied gas storage facility. The method according to any one of claims 1 to 8,
The first and second attachment flanges (21, 22) have a dimension greater than 30 mm in the thickness direction of the sealing tank. The method according to any one of claims 1 to 9,
The first panel 13 comprises a first anchor portion 15 extending between the second load-bearing wall 103 and the sealing membrane 104 of the second wall 101, and , The second panel (14) comprises a second fixing portion (16) extending between the first load-bearing wall (3) and the sealing membrane (4) of the first wall (1), 1 connecting plate (19) is attached to the first fixing portion (15), and the second connecting plate (20) is attached to the second fixing portion (16), liquefied gas storage facility. The method according to any one of claims 1 to 9,
The insulating barrier (2, 102) is a secondary insulating barrier (2, 102) and the sealing membrane (4, 104) is a secondary sealing membrane (4, 104), the first tank wall (1) and the second tank wall 101 is a primary supported by the secondary insulating barrier (2, 102), the secondary sealing membrane (4, 104), and the secondary sealing membrane (4, 104) in the thickness direction from the outside of the tank to the inside. A liquefied gas storage facility, further comprising an insulating barrier (5, 105), and a primary sealing membrane (6, 106) supported by the primary insulating barrier (5, 105). The method of claim 11,
The first connecting plate 19 is attached to the first panel 13 between the primary insulating barrier 5 of the first wall 1 and the secondary insulating barrier 2 of the first wall 1 , The second connection plate 20 is attached to the second panel 14 between the primary insulating barrier 105 of the second wall 101 and the secondary insulating barrier 102 of the second wall 101 Become, liquefied gas storage facilities. A method of manufacturing a liquefied gas storage facility comprising a load-bearing structure and a sealed and insulating tank disposed within the load-bearing structure,
The tank 71 is attached to at least a first tank wall (1) attached to the first load-bearing wall (3) of the load-bearing structure and a second load-bearing wall (103) of the load-bearing structure. A second tank wall (101), each tank wall (1, 101) comprising at least one sealing membrane (4, 104) and at least one insulating barrier (2, 102), the insulating barrier (2, 102) is arranged between the sealing membrane (4, 104) and the load-bearing structure, the storage facility having an edge (100) between the first and second load-bearing walls (3, 103). Thus, it comprises a connection structure 11 configured to attach the sealing membranes 4, 104 to a load-bearing structure,
The connection structure 11 includes a first panel 13 parallel to the first load-bearing wall 3 and attached in a sealing manner to the sealing membranes 4 and 104 of the first tank wall 1 A main beam consisting of a second panel 14 parallel to the second load-bearing wall 103 and attached in a sealing manner to the sealing membranes 4 and 104 of the second tank wall 101 ( 12), wherein the connection structure 11 is also attached to the first panel 13 and extending parallel to the first panel 13 in the direction of the second load-bearing wall 103 At least one first connecting plate 19 and at least one attached to the second panel 14 and extending parallel to the second panel 14 in the direction of the first load-bearing wall 3 It includes a second connection plate 20,
The load-bearing structure comprises at least one first attachment flange (21) protruding parallel to the first tank wall (1) from the second load-bearing wall (103) at a distance from the edge (100) and , At least one second attachment flange (22) protruding parallel to the second tank wall from the first load-bearing wall at a distance from the edge (100),
The first connection plate 19 is attached to the first attachment flange 21, the second connection plate 20 is attached to the second attachment flange 22,
The sealing membranes 4 and 104 and the main beam 12 are made of a metal alloy having a coefficient of thermal expansion between ^{1.2x10 -6} and 7.5x10 ^-6 K ^{-1 (including a boundary value),}
The method is:
-Selecting a material of at least the first and second attachment plates having a coefficient of thermal expansion between ^{20x10 -6} and 60x10 ^-6 K ^{-1 (including a boundary value),}
-Selecting a material of the insulating barrier having a coefficient of thermal expansion between ^{20x10 -6} to 60x10 ^-6 K ^{-1 (including a boundary value),}
A first assembly extending between the second load-bearing wall and the second panel 14 of the main beam 12 and comprising the first attachment flange 21 and the first connecting plate 19 is the tank When (71) is cooled from the ambient temperature in the empty state to the equilibrium temperature in the filled state, it has substantially the same heat shrinkage as that of the heat insulation barrier 102 of the second tank wall 101, and the first load-bearing A second assembly extending between the wall (3) and the first panel (13) of the main beam (12) and comprising the second attachment flange (22) and a second connecting plate (20) comprises the tank (71) Liquefaction, in which the selection steps are carried out such that the selected steps are carried out so that when cooled from the ambient temperature in the empty state to the equilibrium temperature in the filled state, it has substantially the same heat contraction as the heat shrinkage of the insulating barrier 2 of the first tank wall 1. How to manufacture a gas storage facility. As a ship 70 for transporting low-temperature liquid products,
The ship comprises a double hull (72) and a storage facility (71) according to any one of claims 1 to 12, wherein a portion of the double hull forms a load-bearing structure of the storage facility, Vessels for transporting liquid products. As a transfer system for low temperature liquid products,
The system comprises insulated pipes (73, 79, 76, 81) arranged in a manner that connects the ship (70) according to claim 14, the tank (71) installed in the hull of the ship to a floating or onshore storage facility (77). ), and a pump for driving the flow of the low-temperature liquid product from the floating or onshore storage facility to the tank of the ship or from the tank of the ship to the floating or onshore storage facility through the insulating pipes, . As a method of loading or unloading a ship (70) according to paragraph 14,
The low-temperature liquid product is transferred from a floating or onshore storage facility 77 to the tank 71 of the ship or from a floating or onshore storage facility ( 77), the method of loading or unloading the ship.

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