CN116951302A

CN116951302A - Tank wall comprising a through duct

Info

Publication number: CN116951302A
Application number: CN202310473098.1A
Authority: CN
Inventors: 马蒂厄·马龙切特; 尼古拉·萨特; P·兰德鲁
Original assignee: Gaztransport et Technigaz SA
Current assignee: Gaztransport et Technigaz SA
Priority date: 2022-04-27
Filing date: 2023-04-27
Publication date: 2023-10-27
Also published as: TW202408878A; FR3135125A1; JP2023163168A; EP4269863A1; KR20230152588A

Abstract

The application relates to a tank wall comprising a through conduit. The sealed and thermally insulated tank has a tank wall, a secondary thermal insulation barrier (9), a secondary sealing membrane (8), a primary thermal insulation barrier (7) and a primary sealing membrane (6). The tank also has a through duct (5) arranged through the wall of the tank. Around the through duct (5), the tank wall has a secondary insulation block (17) forming a secondary insulation barrier (9), a first sealing layer (20) forming a secondary sealing membrane (8), a primary insulation block (35) forming a primary insulation barrier (6) and a closing plate sealingly connected to the primary sealing membrane (6).

Description

Tank wall comprising a through duct

Technical Field

The present application relates to the manufacture of sealed insulated cans. In particular, the present application relates to tanks designed to contain hot or cold liquids, and more particularly to tanks for storing and/or transporting liquefied gases in an offshore load-bearing structure.

Background

Sealed insulated tanks can be used in different industries to store cold or hot products. For example, in the energy industry, such a product may be Liquefied Natural Gas (LNG). Liquefied Natural Gas (LNG) is a liquid that may be stored at atmospheric pressure in land tanks or tanks carried on floating structures at about-163 ℃. In particular, such floating structures include barges, liquefied natural gas carriers for transporting products, and offshore facilities for storage, liquefaction or regasification of products known as FPSOs and FSRUs.

These sealed and thermally insulated tanks are made of one or several sealing membranes associated with the insulating layer. In particular, from document FR 2781557a sealed and thermally insulated tank is known comprising a tank wall fastened to a carrying structure, wherein the tank wall has a multilayer structure comprising, in order, a primary sealing film, a primary thermally insulating barrier, a secondary sealing film and a secondary thermally insulating barrier for contact with the product contained in the tank.

The sealing membrane is sufficiently elastic to withstand forces caused by, for example, hydrostatic pressure, dynamic pressure and/or temperature changes as the cargo moves. However, such sealing films and underlying insulation are relatively fragile and do not necessarily bear the weight of a cradle (e.g., LNG tank loading/unloading cradle). For this purpose, support feet can be provided, as shown in document FR 2961580A.

Furthermore, during storage of such liquids, the thermodynamic conditions of the sealed and insulated tank lead to a certain amount of evaporation, which leads to a variation of the internal pressure of the tank. To control the pressure of these tanks, the boil-off gas is collected and delivered to a boil-off manifold for re-liquefaction or combustion, for example in the propulsion engine of the ship. For this purpose, manifold ducts may be provided, as shown in document FR 2984454A.

Thus, there are different functions of the multilayer structure that may require through-ducts to pass through the tank wall.

Disclosure of Invention

In the above tanks, all elements are deformed by the effect of temperature changes on the tank wall when the tank is filled with a very cold liquid, such as LNG, and when the tank is emptied, resulting in a return to ambient temperature. In addition to these thermal contraction and expansion effects, which occur repeatedly over the life of the sealed and thermally insulated tank, the tank in the vessel is also subjected to stresses due to deformation of the hull of the vessel at sea. This results in fatigue of the component, which must be monitored over time to prevent failure.

One idea of the invention is to increase the fatigue strength of the tank wall in the area around the multilayer structure penetrated by the through duct.

According to one embodiment, the present invention provides a sealed insulated tank arranged in a load-bearing structure to contain a fluid, the sealed insulated tank comprising:

tank wall, the tank wall anchor is in on the bearing structure, the tank wall has multilayer structure, multilayer structure is along the thickness direction from the outside to inside of sealed thermal-insulated jar includes in proper order: a secondary thermal insulation barrier, a secondary sealing film carried by the secondary thermal insulation barrier, a primary thermal insulation barrier carried by the secondary sealing film, and a primary sealing film carried by the primary thermal insulation barrier, the primary sealing film for contact with a fluid contained in the sealed thermal insulation tank, the multilayer structure comprising a primary space disposed between the primary sealing film and the secondary sealing film, the primary space comprising the primary thermal insulation barrier, and

A through duct disposed through the tank wall, the primary sealing membrane being sealingly connected to the through duct,

the tank wall surrounding the through conduit comprises:

a plurality of secondary insulation blocks anchored on the load-bearing structure, the secondary insulation blocks forming the secondary insulation barrier around the through duct, each secondary insulation block having at least one side extending in the thickness direction of the tank wall, the secondary insulation blocks being arranged in relation to each other such that: a channel is formed between the opposite sides of two adjacent secondary insulation blocks,

a sealing layer covering the secondary insulation, the sealing layer forming the secondary sealing film,

a sealing plate arranged parallel to the tank wall, the sealing plate having an inner surface facing the interior of the sealed insulated tank, the inner surface being at the same level as the sealing layer, the sealing plate being arranged around the through duct, the secondary sealing membrane extending to the sealing plate,

an outer conduit extending from the sealing plate toward the outside of the sealed and thermally insulated tank in parallel with the through conduit around the through conduit, the outer conduit communicating with the primary space to allow inert gas to flow between the primary space and the outer conduit,

A plurality of primary insulation blocks disposed on the secondary sealing film, the primary insulation blocks forming the primary insulation barrier around the through duct, a first and a second of the primary insulation blocks each having a side edge extending in a thickness direction of the tank wall, the side edge having a cutout portion for receiving a portion of the through duct and at least one interface portion adjacent to the cutout portion, the interface portion of the first primary insulation block being disposed opposite the interface portion of the second primary insulation block,

the secondary insulation is arranged in relation to the first primary insulation and the second primary insulation to: such that the interface portion of the first primary insulation block and the interface portion of the second primary insulation block do not overlap with the channels between two adjacent secondary insulation blocks in the thickness direction.

These features help to increase the fatigue resistance of the secondary sealing membrane while maintaining a flexible sealing membrane layer disposed across the secondary insulation. In fact, the interface portion of two adjacent primary insulation blocks does not have any overlap in the thickness direction with the channels of the adjacent secondary insulation blocks, avoiding the risk of increasing the stress on the secondary sealing film due to thermal shrinkage or compression forces.

According to embodiments, such a sealed and thermally insulated tank may have one or more of the following features.

According to one embodiment, the sealing layer is a first sealing layer covering the secondary insulation and the tank wall comprises a second sealing layer sealingly secured around the through conduit across the first sealing layer and the inner surface of the sealing plate, the second sealing layer extending the secondary sealing film to the sealing plate.

According to one embodiment, the second sealing layer comprises at least two sealing strips, each sealing strip being arranged across two adjacent secondary insulation blocks.

According to one embodiment, the second sealing layer has two sealing strips aligned with each other on both sides of the through duct so as to cover the channel.

According to one embodiment, the two sealing strips of the second sealing layer are arranged to: perpendicular to at least one interface portion of the first primary insulation block and at least one interface portion of the second primary insulation block.

According to one embodiment, the tank wall comprises two prefabricated panels arranged on both sides of the through duct, each of the prefabricated panels comprising a lower insulation block forming a secondary insulation block, a first sealing layer covering the secondary insulation block, and an upper insulation block arranged in a central region of the first sealing layer and the lower insulation block without covering a peripheral region of the first sealing layer, the upper insulation block being part of the primary insulation barrier, the primary insulation block being arranged between the upper insulation blocks of the two prefabricated panels on the peripheral region of the first sealing layer of the two prefabricated panels and on the channel.

According to one embodiment, the primary sealing film has a plurality of sealing plates sealingly connected to each other at edges of the sealing plates, wherein an upper insulation block of the two prefabricated plates has an anchoring strip at the edges of the sealing plates to anchor the sealing plates to the prefabricated plates, and the primary insulation block has a thermal protection strip at the edges of the sealing plates such that the sealing plates are not anchored to the primary insulation block.

According to one embodiment, the primary sealing film comprises at least one series of corrugations comprising corrugations extending along quasi-lines parallel to each other, the corrugations protruding towards the interior of the sealed and thermally insulated tank, and wherein a window interrupts the quasi-line of at least one of the series of corrugations, preferably the corrugations have an open end at the window, the sealed and thermally insulated tank having at least one end piece for closing the open end of the at least one corrugation.

According to one embodiment, the window interrupts at least two directrixes of the corrugations in the at least one series of corrugations, and the through conduit is centered at a position between the two directrixes of the interrupted corrugations.

The arrangement and features described above for a series of parallel corrugations may be applied to a plurality of series of parallel corrugations extending in different directions, if necessary.

According to one embodiment, the primary sealing film has a first series of corrugations and a second series of corrugations intersecting the first series of corrugations, the window interrupts at least two quasi-lines of corrugations in the first series of corrugations and at least two quasi-lines of corrugations in the second series of corrugations, and the through conduit is centered at a position between the two interrupted quasi-lines of corrugations in the first series of corrugations and the two interrupted quasi-lines of corrugations in the second series of corrugations.

According to one embodiment, the directrix of the corrugations in the first series of corrugations is perpendicular to the directrix of the corrugations in the second series of corrugations.

The window may have different shapes, in particular depending on the shape of the through duct and/or the shape of the constituent parts of the primary sealing membrane.

According to one embodiment, the window is a quadrilateral, two sides of the quadrilateral being parallel to the directrix of the corrugations in the first series of corrugations, and the other two sides being parallel to the directrix of the corrugations in the second series of corrugations. In particular, the window may be square, rectangular or parallelogram.

According to one embodiment, the through duct has a circular cross-section and passes through the centre of the window.

According to one embodiment, the outer duct comprises a first peripheral connection plate and a second peripheral connection plate, the second peripheral connection plate being sealingly fastened to the first peripheral connection plate around the whole of the first peripheral connection plate, the first peripheral connection plate extending from the second peripheral connection plate to the outside of the sealed insulated tank in a manner parallel to the through duct, the second peripheral connection plate being sealingly fastened to the sealing plate and protruding towards the carrying structure in a manner parallel to the through duct.

According to one embodiment, the tank wall also has at least one closing plate arranged on the primary insulation block around the through duct and sealingly connected to the through duct.

According to one embodiment, the closing plate is constituted by a unitary metal plate surrounding the through duct.

According to one embodiment, at least one of the primary insulation blocks has at least one slot, wherein the closing plate has at least one slot, the slot of the closing plate being covered by an end piece and superposed on the slot of the primary insulation block so as to allow inert gas to flow between the corrugation and the outer conduit.

According to one embodiment, the tank wall has a heat protection plate interposed between the primary insulation block and the closing plate.

Advantageously, the heat protection plate is integrally wrapped around the through duct.

Advantageously, the heat protection plate comprises at least one groove superposed on and under one groove of the primary insulation block.

According to one embodiment, the through conduit forms a passage between the interior of the sealed insulated tank and a steam manifold arranged outside the sealed insulated tank.

Such tanks may be part of an onshore storage facility, such as an onshore storage facility for storing liquefied gas, or mounted on a coastal or deepwater floating structure, in particular a liquefied natural gas carrier, an LPG carrier, a floating storage and regasification unit (floating storage and regasification unit, FSRU), a floating production and storage and offloading (floating production, storage and unloading, FPSO) unit, etc.

According to one embodiment, the present invention also provides a vessel for transporting a cold liquid product, the vessel having a double hull and sealed insulated tanks arranged in the double hull.

According to one embodiment, the invention also provides the use of the vessel for loading or unloading a cold liquid product, wherein the cold liquid product is guided from a sealed insulated tank on the vessel to a land or floating storage facility by means of an insulated pipeline or from a land or floating storage facility to a sealed insulated tank on the vessel by means of the insulated pipeline.

According to one embodiment, the invention also provides a transfer system for cold liquid, the system comprising the vessel, an insulated conduit arranged to connect a sealed insulated tank mounted in the hull of the vessel to a land or floating storage facility, and a pump for driving cold liquid product from the sealed insulated tank on the vessel to the land or floating storage facility via the insulated conduit or from the land or floating storage facility to the sealed insulated tank on the vessel via the insulated conduit.

Drawings

The invention may be better understood and its additional objects, details, features and advantages will be more clearly set forth in the following detailed description of several specific embodiments thereof, given by way of non-limiting example only, with reference to the accompanying drawings.

Fig. 1 is a cross-sectional view of a tank wall including a fluid collection device according to one embodiment of the invention.

Fig. 2 is an enlarged sectional view of region II in fig. 1.

Fig. 3 is a partially exploded perspective view of the tank wall area shown in fig. 2.

Fig. 4 is a plan view along the axis of the through conduit of the tank wall region shown in fig. 2, showing the secondary insulation barrier surrounding the through conduit, with the primary insulation barrier omitted.

Fig. 5 is a view similar to fig. 4 showing the primary thermal insulation barrier.

Fig. 6 is an exploded perspective view of a primary insulation block that may be used in the primary insulation barrier.

Fig. 7 is a view similar to fig. 5 showing the positioning of the heat protection plate and the heat protection strips on the primary insulation barrier.

Fig. 8 is a view similar to fig. 7 and at an intermediate stage of assembly of the primary sealing film.

Fig. 9 is a view similar to fig. 8 and at a further stage of assembly of the primary sealing film.

Fig. 10 is a view similar to fig. 9 showing the primary sealing film.

Fig. 11 is a perspective view of an end piece that may be used in manufacturing the primary sealing film shown in fig. 10.

Figure 12 is a cross-sectional view of a tank in a lng carrier and a loading/unloading terminal for the tank.

Detailed Description

Referring to fig. 1, a sealed insulated tank 1 has a tank wall 2 secured to the inner surface of a corresponding wall of a load bearing structure 3. The carrier structure 3 is for example the inner hull of a double hull vessel or an onshore structure. Fig. 1 is a partial view of a sealed insulated tank 1, only the top wall being shown.

Conventionally, the terms "upper", "above", "upper" and "top" generally refer to a position towards the inside of the sealed insulated tank 1, while the terms "lower", "below", "lower" and "bottom" generally refer to a position towards the outside of the sealed insulated tank 1, irrespective of the orientation of the tank wall 2 with respect to the earth's gravitational field.

The sealed and thermally insulated tank 1 may have different geometries, such as prismatic geometry in the hull or cylindrical geometry on land, or other shapes.

The following embodiments are described in relation to a sealed and thermally insulated tank 1 for offshore storage and/or transportation of liquefied natural gas. In a variant not described, such a sealed and thermally insulated tank 1 may be a tank for storing other cold or hot products on land.

Fig. 1 and 2 show a fluid collection device 4. The device comprises a through duct 5 passing through the tank wall 2, for example sealing the top wall of the insulated tank 1.

Referring to fig. 1, a tank wall 2 has, in order from the inside of a sealed and thermally insulated tank 1 toward a load-bearing structure 3, in a thickness direction: a primary sealing membrane 6 in contact with the liquefied gas, a primary thermal insulation barrier 7, a secondary sealing membrane 8 and a secondary thermal insulation barrier 9. The primary thermal insulation barrier 7, the secondary sealing film 8 and the secondary thermal insulation barrier 9 are essentially a set of preformed sheets which are placed on the adhesive bead 11 and fastened to the load-bearing structure 3.

The fluid collection device 4 comprises a cylinder 12 extending outside the carrying structure 3, and a through duct 5 anchored inside the cylinder 12. The cylinder 12 and the through duct 5 are cylindrical bodies having circular cross sections. However, other shapes are also possible. The carrier structure 3 has a circular opening 13. The cylinder 12 is welded around the circular opening 13. The through duct 5 passes through the tank wall 2 at the centre of the circular opening 13. Thus, the through duct 5 passes through the primary sealing membrane 6, the secondary sealing membrane 8, the primary thermal insulation barrier 7 and the secondary thermal insulation barrier 9 into the sealed thermal insulation tank 1. In particular, the through duct 5 is connected to a steam manifold external to the sealed insulated tank, which extracts the steam and delivers it to the propulsion system of the ship to power the ship, or to the liquefaction system to subsequently return the liquefied gas to the tank.

The primary sealing membrane 6 is sealingly connected to the through duct 5. The secondary sealing membrane 8 is also sealingly connected to the through duct 5 except at a channel that enables the gas phase between the primary sealing membrane 6 and the secondary sealing membrane 8 to flow to the two secondary ducts 14, 15. The gas phase is typically molecular nitrogen or other inert gas. Thus, the space between the primary sealing membrane 6 and the secondary sealing membrane 8 forms a primary sealing space which is connected to the two secondary ducts 14, 15.

Furthermore, the cylinder 12 is sealingly connected to the carrier structure 3. The insulating layer 16 is uniformly distributed on the outside of the through duct 5, the diameter of which is smaller than the diameter of the circular opening 13. In this way, the gap between the insulating layer 16 and the circular opening 13 enables a gas phase to flow between the secondary insulation barrier 9 and the intermediate space between the cylinder 12 and the insulating layer 16. The gas phase is typically molecular nitrogen or other inert gas. The intermediate space and the space between the load-bearing structure 3 and the secondary heat insulation barrier 9 thus form a secondary sealed space.

In the insulating layer 16, two secondary ducts 14, 15 extend from the outside of the cylinder 12 to the primary sealed space in parallel to the through duct 5. The first secondary conduit 14 provides a passage between the primary sealed space and a discharge member (not shown) controlling the gas phase in the primary space. The second secondary conduit 15 provides a passage between the primary space and a pressure measuring device (not shown). In particular, the two secondary ducts 14, 15 enable flushing of the primary sealed space with an inert gas (for example nitrogen).

Two further conduits (not shown) are welded to the cylinder 12 and open into the secondary sealed space inside the cylinder 12, also enabling the management of the gas phase and the measurement of the pressure in the secondary sealed space. The conduit connected to the secondary sealed space also enables flushing of the secondary sealed space with an inert gas, such as nitrogen.

The region II of the tank wall 2 penetrated by the through duct 5 is described in more detail below with reference to fig. 2 to 10.

Two prefabricated panels 10a, 10b are arranged close to the through duct 5. Referring to fig. 4, the prefabricated panels 10a, 10b have secondary insulation blocks 17 anchored to the load bearing structure 3. The secondary insulation 17 has a rigid base plate 18 supported by adhesive droplets 11 and an insulation layer 19 made of polyurethane foam.

A first sealing layer 20 of composite material, for example a layer of glass fibres comprising metal sheets and impregnated resin, is adhered to the entire surface of the insulating layer 19 of the secondary insulating block 17. The first sealing layer 20 is an integral part of the secondary sealing film 8.

The prefabricated panels 10a, 10b further include upper insulation blocks 21a, 21b. The upper insulation blocks 21a, 21b have an insulation layer 22 made of polyurethane foam, which partially covers and adheres to the first sealing layer 20. A rigid top plate 23 covers the insulation layer 22 and forms, together with the insulation layer, the constituent elements of the primary insulation barrier 7.

As explained above with reference to fig. 1, the through duct 5 passes through the circular opening 13, the secondary thermal insulation barrier 9, the secondary sealing membrane 8, the primary thermal insulation barrier 7 and the primary sealing membrane 6. A circular closing plate 24 extends around the through duct 5 in an area beyond the carrying structure 3. The closing plate 24 has an upper surface parallel to the tank wall 2, to which an insulating layer 16 surrounding the through duct 5 is glued. The closing plate 24 also has two holes 25, 26 to which the two secondary ducts 14, 15 are welded.

The seal between the secondary thermal insulation barrier 9 and the through duct 5 is achieved by means of the closing plate 24, the first peripheral connection plate 27, the second peripheral connection plate 28 and the sealing plate 29. A tubular first peripheral web 27 is sealingly fastened to the closure plate 24 around its entire periphery and extends into the sealed insulated tank 1 in parallel to the through duct 5 to form an outer duct. Which is connected at the end opposite the closing plate 24 to a circular sealing plate 29 by a second peripheral connecting plate 28, which is likewise tubular. Thus, the closing plate 24, the sealing plate 29 and the peripheral connection plates 27, 28 form an inner space 30 in the outer duct, said inner space 30 being adjacent to the outer wall of the through duct 5. The second seal layer 31 is sealingly fixed to the first seal layer 20 and the seal plate 29 to seal the secondary seal film 8.

The sealing plate 29 has a circular channel 32 through which the through duct 5 passes. The diameter of the circular channel 32 is larger than the diameter of the through duct 5, leaving a gap between the sealing plate 29 and the through duct 5. The gap enables the gas phase to flow from the primary seal space between the primary seal membrane 6 and the secondary seal membrane 8 toward the inner space 30.

To remove steam from the interior space 30, the two secondary ducts 14, 15 are sealingly connected to the closing plate 24. This structure enables flushing with inert gas. To provide insulation, the interior space 30 is filled with a vapor and gas permeable insulation material.

The second peripheral connection plate 28 is tubular and welded to the lower surface of the sealing plate 29. The inner diameter of the second peripheral web 28 is substantially equal to the outer diameter of the first peripheral web 27. Thus, the peripheral webs 27, 28 may be assembled together and slidingly mated without welding. Thus, when the second peripheral web 28 is welded to the first peripheral web 27, the gap between the sealing plate 29 and the carrier structure 3 can be adjusted to accurately align the sealing plate 29 with the secondary sealing membrane 8. Furthermore, fitting the first and second peripheral connection plates 27, 28 together enables centering of the through duct 5 in the opening 13 and orientation of the sealing plate 29. Welds between the closure plate 24 and the first peripheral web 27, between the first peripheral web 27 and the second peripheral web 28, and between the second peripheral web 28 and the sealing plate 29 are made to form seals between these elements.

The closing plate 24, the sealing plate 29, the first peripheral connection plate 27 and the second peripheral connection plate 28 are metal elements, for example made of stainless steel.

Referring to fig. 1, in order to reduce the forces exerted on the adhesive bond formed around the through duct 5, the through duct is anchored at a portion 33 of the through duct, said portion 33 being spaced apart from the load-bearing structure 3 in a direction away from the inside of the sealed insulated tank 1. This reduces the stress on the adhesion of the tank wall 2. Such anchoring comprises a frustoconical metal element 34 extending into the barrel 12.

Referring to fig. 1 and 2, the fins 40 are regularly arranged in the inner space 30 between the through duct 5 and the first peripheral connection plate 27 to position and fix the first peripheral connection plate 27 with respect to the through duct 5.

Referring to fig. 2 to 5, two primary insulation blocks 35 are arranged across the secondary insulation blocks 17 and the sealing plates 29 of the prefabricated panels 10a, 10b to form a primary insulation barrier 7 between the through duct 5 and the prefabricated panels 10a, 10 b. As with the upper insulation blocks 21a, 21b, the primary insulation block 35 has an insulation layer 36 against the secondary insulation barrier 9. A top plate 37 is arranged on top of the insulating layer 36.

The upper insulation blocks 21a, 21b and the primary insulation block 35 of the prefabricated panels 10a, 10b support the primary sealing film 6, which is made of a metal plate with corrugations 38a, 38 b. These corrugations 38a, 38b form elastic regions intended to absorb thermal contraction as well as static and dynamic compressive forces. Such corrugated or checkerboard metal seal barriers are described in detail in FR 1379651A, FR 1376525A, FR 2781557A and FR 2861060A.

The primary sealing membrane 6 is sealingly connected to the through-conduit 5 by means of a flange 39 having an L-shaped cross-section. The flange 39 is welded to the primary sealing membrane 6 and the through duct 5.

Fig. 3 shows in more detail the structure of the elements forming the tank wall 2 around the through duct 5.

The through duct 5 and the first peripheral connection plate 27 pass through the carrier structure 3 at the centre of the opening 13. The first peripheral web 27 is centered in the opening.

A glass wool packing is inserted into the inner space 30. As previously mentioned, the packing is porous to enable free flow of the gas phase in the interior space 30 between the primary and secondary conduits 14, 15 (not shown in fig. 3).

By welding the second peripheral web 28 to the first peripheral web 27, the sealing plate 29 is positioned in precise alignment with the secondary sealing membrane 8. In order to avoid the risk of burning out the glass wool filler, a thermal protection (not shown) is provided between the filler and the peripheral connection plates 27, 28.

Referring to fig. 3 to 5, the secondary heat insulation barrier 9, the secondary sealing film 8 and the primary heat insulation barrier 7 are made of two prefabricated panels 10a, 10 b. Each prefabricated panel 10a, 10b surrounding the through duct 5 is stepped so that the secondary insulation block 17 constitutes a constituent element of the secondary insulation barrier 9, the first sealing layer 20 completely covers the upper surface of the secondary insulation block 17, and the smaller upper insulation blocks 21a, 21b constitute a constituent element of the primary insulation barrier 7. The upper insulation blocks 21a, 21b of the prefabricated panels 10a, 10b have a U-shaped cross section when viewed from above, and are positioned with respect to the secondary insulation block 17 such that the peripheral region of the first sealing layer 20 is exposed.

Specifically, each secondary insulation block 17 has a side 41 with a semicircular cutout to accommodate the first and second perimeter connection plates 27, 28. As shown in fig. 2, the semi-circular shape has a diameter larger than the diameters of the first and second peripheral connection plates 27, 28, leaving a space for inserting the glass wool filler 73 between the first and second peripheral connection plates 27, 28 and the secondary insulation block 17.

The two secondary insulation blocks 17 are designed to: forming a space in the form of two radial inter-plate passages (42 a, 42 b) between the blocks. To ensure continuity of the secondary insulation barrier 9, each of the two radial inter-plate channels 42a, 42b is filled with a glass wool filler (not shown) that allows a gas phase to flow through the secondary insulation barrier 9, which is particularly used to inertize the tank wall with an inert gas (such as nitrogen).

The prefabricated panels 10a, 10b may be prefabricated by bonding with polyurethane foam and plywood for the primary and secondary heat insulation barriers 7, 9. Accordingly, the secondary insulation block 17 comprises a bottom plate 18 and an insulating foam layer 19, and the upper insulation blocks 21a, 21b comprise an insulating layer 22 and a top plate 23. The top plate 23 of the upper insulation block 21a, 21b has transverse and longitudinal countersink surfaces designed to receive an anchor strip 43 to which the primary sealing film 6 is welded, as described below.

Two prefabricated panels 10a, 10b are juxtaposed to surround the through duct 5. Each prefabricated panel 10a, 10b also has a channel 44 that enables access to pins 71 previously welded to the load bearing structure during assembly to anchor the prefabricated panel 10a, 10b.

The second sealant 31 is bonded across the first sealant 20 and is bonded to the sealing plate 29. The second sealing layer 31 further comprises two radial sealing strips 31a, 31b arranged across the two secondary insulation blocks 17 above the channels 42a and 42 b.

Two primary insulation blocks 35 and two intermediate blocks 45 are located above the second seal layer 31 and the first seal layer 20 to complete the primary insulation barrier 7. The intermediate blocks 45 are mounted on the radial sealing strips 31, 31b of the second sealing layer 31.

Referring to fig. 6, each primary insulation block 35 has a side 46 with a semicircular cutout 76 to accommodate the through duct 5, and a straight interface portion 47 adjacent the cutout 76. When the primary insulation block 35 is assembled, the cutout 76 defines a diameter that is greater than the diameter of the through conduit 5, as shown in fig. 2.

Referring to fig. 5, the two primary insulation blocks 35 are designed to meet without touching at the two interface portions 47. The two primary insulation blocks 35 are located above the second seal layer 31 such that the interface portion 47 and the radial inter-plate channels 42a, 42b do not overlap in the thickness direction. In FIG. 3, the direction D of the interface portion 47 of the primary insulation block 35 ₁ Direction D perpendicular to the radial inter-plate channels 42a, 42b ₂ 。

Referring to fig. 9 and 10, the primary sealing membrane 6 is formed of a plurality of corrugated sealing plates 48, the inner surfaces of which are intended to be in contact with the fluid contained in the sealed insulated tank 1. The seal plate 48 is a thin metal member such as a stainless steel plate. These corrugated sealing plates 48 are cut to form square windows 49 around the through duct 5, allowing the through duct 5 to pass through. In this example, the window 49 is square, which is advantageous for cutting the seal plate 48 into the desired shape. However, the window 49 may also have a different shape, depending inter alia on the geometry of the through duct 5.

The sealing plate 48 of the primary sealing film 6 has a plurality of corrugations 38a, 38b protruding toward the inside of the sealed and insulated tank 1. More specifically, the primary sealing film 6 has a first series of waves 38a called transverse waves and a second series of waves 38b called longitudinal waves, which are arranged perpendicular to each other. The first series of corrugations 38a are taller than the second series of corrugations 38b.

In fig. 9, the edges of the sealing plate 48 are shown with continuous lines. The sealing plates 48 are welded together in the rim overlap region 77 to seal the primary sealing film 6. The weld is a lap weld and the related method is described in detail in, for example, patent FR 1387955A. The seal plate 48 may be made in a variety of shapes and sizes so that the weld area may be positioned differently.

Unlike the upper insulation blocks 21a, 21b of the prefabricated panels 10a, 10b, the primary insulation block 35 does not have the anchor strip 43. In fact, in order to make the primary sealing membrane 6 surround the through duct 5, as shown in fig. 3 and 8 to 10, the closing plate 51 arranged on the heat protection plate 72 defines a square slightly larger in size than the window 49 provided in the sealing plate 48. The centre of the closing plate 51 is cut with an opening to allow the through conduit 5 to pass through. The closing plate 51 is sealingly welded to the through duct 5 via the flange 39.

Referring to fig. 7 to 9, the sealing plate 48 of the primary sealing film 6 is welded to the anchoring strips 43 and the intermediate blocks 45 of the upper insulation blocks 21a, 21 b. The sealing plate 48 is welded to the anchor strip 43 so that the primary sealing film 6 can be held on the primary insulation barrier 7. To prevent damage to the primary insulation 35, particularly when welding the seal plates 48 together, a thermal protection strip 50 is disposed on the primary insulation 35 at the edges of the seal plates 48. The heat protection plate 72 and the heat protection strip 50 are made of a heat resistant material such as a composite glass fiber material. An opening is cut in the center of the heat shield plate 72 to allow the through conduit 5 to pass through.

The primary sealing membrane 6 surrounding the through duct 5 is first completed by first welding the edge of the sealing plate 48 defining the window 49 to the closing plate 51 and then sealing the ends of the interrupted corrugations 38a, 38b with the end piece 52. In fact, since the diameter of the through duct 5 is greater than the gaps between the corrugations in the first series of corrugations 38a, some of the transverse corrugations, where the directrix intersects the through duct, are interrupted by windows 49. Similarly, since the diameter of the through-conduit 5 is larger than the gaps between the corrugations in the second series of corrugations 38b, some of the longitudinal corrugations intersecting the through-conduit 5 are interrupted by windows 49 around the through-conduit 5.

Referring to fig. 11, the end piece 52 has two-part base plates 53, 54 and a housing 55, the two-part base plates 53, 54 being designed to be sealingly welded to the closing plate 51 and the sealing plate 48, respectively, and the housing being designed to be sealingly welded to the ends of the corrugations. The width of the recess 56 between the portions 53, 54 of the base plate is substantially equal to the thickness of the sealing plate 48.

Referring to fig. 3, 5 and 6, the top plate 37 of the primary insulation block 35 has four slots 57 extending through the top plate 37, the closing plate 51 has slots 69 overlying the slots 57 of the primary insulation block 35, and the heat protecting plate 72 has slots 70 overlying the slots 57 of the primary insulation block 35 and underlying the slots 69 of the closing plate 51. During installation of the primary sealing membrane 6, the end pieces 52 are superposed on the grooves 57, 69, 70 so as to enable the gas phase in the corrugations 38a, 38b to flow towards the insulating layer 36 of the primary insulation block 35. The insulating layer 36 also has a connecting slot 74 below the slot 57 of the top plate 37, from which three parallel slots 75 extend respectively towards semi-circular cutouts 76 in the primary insulation block 35. Thus, the gas phase having passed through the top plate 37 can flow to the outside of the primary insulation block 35, and enter into the space between the primary insulation block 35 and the through duct 5.

This particular structure of the primary insulation 35, coupled with the gap between the circular channel 32 and the through duct 5 and the internal space 30 comprising porous filler, establishes a circuit promoting the flow of the gas phase in the primary sealed space, in particular from the corrugations 38a, 38b to the secondary ducts 14, 15 and vice versa. Similarly, as described above, the space between the opening 13 and the first peripheral connection plate 27 and between the load-bearing structure 3 and the secondary insulation 17 forms a circuit that promotes the flow of gas phase between the secondary sealed space and the cylinder 12. These circuits enable, inter alia, the tank wall 2 to be inerted with an inert gas, such as nitrogen molecules.

Figures 9 and 10 show that the size of the window 49 is actually larger than the diameter of the through duct 5. Thus, the window 49 formed in the primary sealing film 6 also tends to interrupt the corrugations that closely approximate the guideline to the through conduit 5 without actually intersecting the through conduit 5.

As shown in fig. 9 and 10, the center of the through duct 5 is located between the directrixes of the interrupted transverse corrugations 38a and between the directrixes of the interrupted longitudinal corrugations 38b, more precisely the center of the through duct is located at the center of these directrixes. As a result of this positioning, the directrix intersects the through duct 5 in any case along a chord shorter than the diameter of the through duct 5. Thus, this positioning of the through duct 5 allows to interrupt the transverse corrugation 38a or the longitudinal corrugation 38b over a shorter distance, considering the space between the edge of the window 49 and the through duct 5, compared to the case where the quasi-line intersects the through duct 5 along its largest transverse or longitudinal dimension (i.e. its diameter), since in this case the through duct 5 is a cylinder with a circular cross section. In view of the ease with which these interruptions locally reduce the flexibility of the primary sealing film 6 and thereby increase the likelihood of local fatigue and wear, it is beneficial to interrupt the corrugations 38a, 38b of the primary sealing film 6 over as short a distance as possible.

Centering the through duct 5 in the middle between the interrupted transverse corrugation 38a and the interrupted longitudinal corrugation 38b provides the best results. However, other shapes and different centering of the through duct 5 are also contemplated. In each case, one principle that can be used to adjust the positioning of the through duct 5 between the corrugations 38a, 38b is: the position is selected to minimize or at least reduce the size of the through duct 5 intersecting the quasi-line of interrupted corrugations 38a, 38 b. In the case of a specific geometry of the primary sealing film 6 such that several corrugations 38a, 38b are interrupted over different lengths, the relevant parameter for optimizing the positioning of the through duct 5 may be the length of the longest interruption or the cumulative length of these obtained interruptions.

A window 49 of approximately twice the size of the gap between the two corrugations 38a, 38b is required for the through duct 5, in this case the two corrugations 38a, 38b being equidistant. To this end, the two corrugations 38a, 38b in each series are interrupted. However, this arrangement of the through duct 5 and the tank wall 2 in its vicinity can also be adapted to other dimensions of the through duct 5. For example, for larger through-catheters, the respective windows 49 may interrupt a greater number of corrugations 38a, 38b in one or each series, e.g., three or four or more corrugations.

Although in the above described embodiment the through duct 5 passes through the top wall of the sealed insulated tank 1, in another embodiment the through duct may pass through the tank wall 2 at the top of the side wall of the sealed insulated tank 1 or through the tank wall at any other location in said sealed insulated tank 1.

The sealed and insulated tank 1 described above may be used in different types of installations (e.g. land-based installations) or in floating structures (e.g. lng carriers etc.).

Referring to fig. 12, a cross-sectional view of the lng carrier 58 shows the sealed insulated tank 1 having an overall prismatic shape mounted in a double hull 59 of the lng carrier 58.

The tank wall 2 comprises a primary sealing membrane 6 for contact with LNG contained in the sealed insulated tank 1, a secondary sealing membrane 8 arranged between the primary sealing membrane 6 and the double hull 59 of the LNG carrier, and two heat insulating barriers 7, 9 arranged between the primary sealing membrane 6 and the secondary sealing membrane 8 and between the secondary sealing membrane 8 and the double hull 59 of the LNG carrier 58, respectively.

In a known manner, the loading/unloading piping 60 arranged on the upper deck of the LNG carrier 58 may be connected to an offshore or port terminal using suitable connectors to transfer liquefied gas cargo, such as LNG, to the insulated tank 1 or from the insulated tank 1.

Fig. 12 also shows a marine terminal comprising a loading/unloading point 61, a subsea pipeline 62 and a land-based facility 63.

The loading/unloading point 61 is a static offshore facility comprising a movable arm 64 and a column 65 holding the movable arm 64. The movable arm 64 carries a bundle of insulated hoses 66 that may be connected to the loading/unloading duct 60. The orientable movable arm 64 may fit all sizes of lng carriers 58. A connecting line (not shown) extends within column 65. The loading/unloading point 61 enables unloading from the lng carrier 58 to an onshore facility 63 or loading from an onshore facility to the lng carrier. The facility has a liquefied gas storage tank 67 and a connection line 68 connected to the loading/unloading point 61 via a subsea line 62.

The undersea pipeline 62 enables liquefied gas to be transported over a large distance (e.g., 5 km) between the loading/unloading point 61 and the onshore facility 63, which enables the liquefied natural gas carrier 58 to remain off shore during loading and unloading operations.

To generate the pressure required to deliver the liquefied gas, pumps carried on lng carrier 58 and/or mounted on land facility 63 and/or mounted on loading/unloading point 61 are used.

While the invention has been described in connection with a number of specific embodiments, it is to be understood that the invention is not limited thereto and includes all technical equivalents of the means described and combinations thereof, which fall within the scope of the invention.

Use of the verb "to comprise" or "to comprise" does not exclude the presence of other elements or steps than those mentioned in the claims.

In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim.

Claims

1. A sealed and thermally insulated tank (1) arranged in a load-bearing structure (3) to contain a fluid, the sealed and thermally insulated tank (1) comprising:

-a tank wall (2) anchored on the load-bearing structure (3), the tank wall (2) having a multilayer structure comprising, in order from the outside to the inside of the sealed and thermally insulated tank (1) in the thickness direction: a secondary thermal insulation barrier (9), a secondary sealing membrane (8) carried by the secondary thermal insulation barrier (9), a primary thermal insulation barrier (7) carried by the secondary sealing membrane (8), and a primary sealing membrane (6) carried by the primary thermal insulation barrier (7) for contact with a fluid contained in the sealed thermal insulation tank (1), the multilayer structure comprising a primary space arranged between the primary sealing membrane (6) and the secondary sealing membrane (8), the primary space comprising the primary thermal insulation barrier (7), and

-a through duct (5) provided through the tank wall (2), the primary sealing membrane (6) being sealingly connected to the through duct (5), the tank wall (2) comprising around the through duct (5):

-a plurality of secondary insulation blocks (17) anchored to the load-bearing structure (3)

On, the secondary insulation blocks (17) form the secondary insulation barrier (9) around the through duct (5), each secondary insulation block (17) having at least one side extending in the thickness direction of the tank wall (2), the secondary insulation blocks (17) being arranged in relation to each other such that: forming a channel (42 a,42 b) between opposite sides of two adjacent secondary insulation blocks (17),

-a sealing layer (20) covering the secondary insulation (17), the sealing layer (20) forming the secondary sealing film (8),

-a sealing plate (29) arranged parallel to the tank wall (2), the sealing plate (29)

Having an inner surface facing the interior of the sealed and thermally insulated tank (1), said inner surface being at the same level as the sealing layer (20), the sealing plate being arranged around the through duct (5),

the secondary sealing membrane (8) extends to the sealing plate (29),

-an outer conduit (27, 28) extending around the through conduit (5) in parallel to the through conduit (5), the outer conduit (27, 28) being in communication with the primary space to allow an inert gas to flow between the primary space and the outer conduit (27, 28),

-a plurality of primary insulation blocks (35) arranged on the secondary sealing film (8), forming the primary insulation barrier (7) around the through duct (5),

the first and second ones of the primary insulation blocks (35) each have a side edge extending in the thickness direction of the tank wall (2), the side edge (46) having a cutout portion (76)

And at least one interface portion (47) adjacent to the cut-out portion (76) for receiving a portion of the through duct (5), the interface portion (47) of the first primary insulation block (35) being arranged opposite to the interface portion (47) of the second primary insulation block (35),

the secondary insulation (17) and the first and second primary insulation (35) are arranged in relation to each other: such that the interface portion (47) of the first primary insulation block (35) and the interface portion (47) of the second primary insulation block (35) do not overlap in the thickness direction with the channels (42 a,42 b) between two adjacent secondary insulation blocks (17).

2. Sealed and thermally insulated tank (1) according to claim 1, wherein the sealing layer (20) is a first sealing layer covering the secondary insulation block (17) and the tank wall comprises a second sealing layer (31) sealingly secured around the through duct (5) across the inner surfaces of the sealing layer (20) and the sealing plate (29), the second sealing layer (31) extending the secondary sealing membrane (8) to the sealing plate (29).

3. Sealed and thermally insulated tank (1) according to claim 2, wherein the second sealing layer (31) comprises at least two sealing strips (31 a,31 b), each sealing strip (31 a,31 b) being arranged across two adjacent secondary thermally insulated blocks (17).

4. A sealed and thermally insulated tank (1) according to claim 3, wherein the two sealing strips (31 a,31 b) of the second sealing layer (31) are aligned with each other on both sides of the through duct (5) to cover the channels (42 a,42 b).

5. Sealed and thermally insulated tank (1) according to claim 3 or 4, wherein the two sealing strips (31 a,31 b) of the second sealing layer (31) are arranged to: perpendicular to at least one interface portion (47) of the first primary insulation block (35) and at least one interface portion (47) of the second primary insulation block (35).

6. Sealed and insulated tank (1) according to any one of claims 2 to 5, wherein the tank wall (2) comprises two prefabricated panels (10 a,10 b) arranged on both sides of the through duct (5), each comprising a lower insulating block forming a secondary insulating block (17), the first sealing layer covering the secondary insulating block (17), and an upper insulating block (21 a,21 b) arranged on a central region of the first sealing layer (20) and the lower insulating block without covering a peripheral region of the first sealing layer (20), the upper insulating blocks (21 a,21 b) being part of the primary insulating barrier (6), the primary insulating blocks (35) being arranged between the insulating blocks (21 a,21 b) on the two prefabricated panels (10 a,10 b) on the peripheral region of the first sealing layer (20) and on the channels (42 a,42 b).

7. Sealed and insulated tank (1) according to claim 6, wherein the primary sealing film (6) has a plurality of sealing plates (48) sealingly connected to each other at the edges (100) of the sealing plates (48), wherein the upper insulation blocks (21 a,21 b) of the two prefabricated plates (10 a,10 b) have anchoring strips (43) at the edges (100) of the sealing plates (48) to anchor the sealing plates (48) to the prefabricated plates (10 a,10 b), the primary insulation blocks (35) having thermal protection strips (50) at the edges (100) of the sealing plates (48) such that the sealing plates (48) are not anchored to the primary insulation blocks (35).

8. Sealed and thermally insulated tank (1) according to any one of claims 1 to 7, wherein the primary sealing film (6) comprises at least one series of corrugations comprising corrugations (38 a,38 b) extending along quasi-lines parallel to each other, the corrugations (38 a,38 b) protruding towards the interior of the sealed and thermally insulated tank (1), and wherein a window (49) interrupts the quasi-line of at least one corrugation (38 a,38 b) of the series of corrugations, preferably the corrugations (38 a,38 b) having an open end at the window (49), the sealed and thermally insulated tank (1) having at least one end piece (52) for closing the open end of the at least one corrugation (38 a,38 b).

9. Sealed and thermally insulated tank (1) according to any one of claims 1 to 8, wherein the outer duct (27, 28) comprises a first peripheral connection plate (27) and a second peripheral connection plate (28), the second peripheral connection plate (28) being sealingly fastened to the first peripheral connection plate (27) around the entire first peripheral connection plate (27), the first peripheral connection plate (27) extending from the second peripheral connection plate to the outside of the sealed and thermally insulated tank (1) in parallel to the through duct (5), the second peripheral connection plate (28) being sealingly fastened to the sealing plate (29) and protruding towards the carrying structure (3) in parallel to the through duct (5).

10. Sealed and thermally insulated tank (1) according to any one of claims 1 to 9, wherein the tank wall (2) further has at least one closing plate (51) arranged on the primary thermally insulating block (35) around a through duct (5) and sealingly connected to the through duct (5).

11. Sealed and thermally insulated tank (1) according to the combination of claims 8 and 10, wherein at least one of the primary thermally insulated blocks (35) has at least one groove (57), wherein the closing plate (51) has at least one groove (69), the groove (69) of the closing plate being covered by one end piece (52) and superposed on the groove (57) of the primary thermally insulated block (35) so as to allow inert gas to flow between the corrugations (38 a,38 b) and the outer duct.

12. Sealed and thermally insulated tank (1) according to claim 10 or 11, wherein the tank wall (2) has a heat protection plate (72) interposed between the primary insulation block (35) and the closing plate (51).

13. Sealed and insulated tank (1) according to any one of claims 1 to 12, wherein the through duct (5) forms a channel between the interior of the sealed and insulated tank (1) and a steam manifold arranged outside the sealed and insulated tank (1).

14. Vessel (58) for transporting a cold liquid product, the vessel (58) having a double hull (59) and a sealed and thermally insulated tank (1) according to any one of claims 1 to 13, the sealed and thermally insulated tank being arranged within the double hull (59).

15. Use of a vessel (58) according to claim 14 for loading or unloading a cold liquid product, wherein cold liquid product is guided from a sealed insulated tank (1) on the vessel (58) to a land or floating storage facility (63) through an insulated conduit (66) or from a land or floating storage facility to a sealed insulated tank on the vessel through the insulated conduit.

16. A transfer system for cold liquid, the system comprising an insulated pipeline (66) arranged to connect a sealed insulated tank (1) installed in the hull of the vessel (58) to a land or floating storage facility (63), a pump for driving cold liquid product from the sealed insulated tank (1) on the vessel (58) to the land or floating storage facility (63) via the insulated pipeline (66), or from the land or floating storage facility to the sealed insulated tank on the vessel via the insulated pipeline.