KR102506308B1 - Sealed and insulated tank containing gas dome structure - Google Patents

Abstract

The present invention relates to a sealed and insulated tank for storing liquefied gas, the tank including an upper wall having a multi-layer structure, the tank further including a gas dome structure (10), the gas dome structure (1) is:
- vapor collection pipe (15);
- a sheath (19) arranged around the vapor collection pipe (15) and sealably connected to the secondary sealing membrane (6), said sheath (19) transversally between the sheath (19) and the vapor collection pipe (15). is sealably connected to the vapor collection pipe 15 by the upper annular plate 20 extending to provide a primary sealed space 22 communicating with the primary thermal insulation barrier 7, and the sheath 19 between the silver upper annular plate 20 and the secondary sealing membrane 6 sheath 19 with a truncated cone portion 43 tapering towards the secondary sealing membrane 6; and
- a primary exhaust device adapted to discharge fluid from the primary thermal insulation barrier (7), comprising a pipe (27) sealably connected to the upper annular plate (20);
includes

Description

Sealed and insulated tank containing gas dome structure

The present invention relates to the field of sealed and insulated tanks for storing and/or transporting fluids, such as cryogenic fluids.

Sealed and insulated tanks are used in particular to store liquefied natural gas (LNG), which is stored at atmospheric pressure of about -162°C.

The prior art, in particular patent application WO 2015/155377, discloses a sealed and insulated tank for storing liquefied natural gas equipped with a gas dome structure. This sealed and insulated tank consists successively in the thickness direction of a secondary thermal insulation barrier lying against the supporting structure, a secondary sealing membrane lying against the secondary thermal insulation barrier, a primary thermal insulation barrier lying against the secondary sealing membrane, and a tank contained therein. It includes walls with a primary sealing membrane adapted to come into contact with the liquefied gas.

The gas dome structure includes a vapor collection pipe for forming a vapor circulation channel between an inner space of the tank and a vapor collector (not shown) disposed outside the tank.

The gas dome structure also incorporates a primary exhaust device that allows gases present within the primary thermal insulation barrier to be expelled. For this purpose, the primary exhaust system comprises a pipe leading to a primary sealed space in communication with the primary thermal insulation barrier of the tank.

Gas dome structures as disclosed in the aforementioned documents are not entirely satisfactory. In particular, the exhaust flow rate of the fluid present in the insulating barrier can only be made by compromising the bulk growth of the gas dome in the vicinity of the secondary sealing membrane, which in some types of tanks the mechanical performance of the secondary sealing membrane. leads to damage in

One idea behind the present invention is a gas dome structure that is equipped with a primary exhaust device that allows the fluid present in the primary thermal insulation barrier to be discharged and can quickly discharge a significant amount of the fluid present in the primary thermal insulation barrier. It is to provide a sealed and insulated tank comprising a, which is to do this without degrading the mechanical performance of the walls of the tank in the vicinity of the gas dome structure.

According to one embodiment, the present invention is a sealed and insulated tank adapted to store liquefied gas, in thickness direction, a secondary thermal insulation barrier lying against a supporting structure, a secondary seal lying against a secondary thermal insulation barrier (5). an upper wall continuously provided with a membrane, a primary thermal insulation barrier placed against the secondary sealing membrane, and a primary sealing membrane adapted to be in contact with a liquefied gas contained in the tank, the tank further comprising a gas dome structure; The gas dome structure is:

- a vapor collection pipe adapted to extract vapors produced by evaporation of liquefied gas in the tank, the vapor collection pipe passing through an opening provided in the supporting structure and passing through the upper wall of the tank, a vapor collection pipe comprising a perimeter wall sealably connected to the primary sealing membrane;

- a cladding disposed around the vapor collection pipe, the cladding comprising a lower end sealably connected to a secondary sealing membrane, the cladding being provided with an upper annular plate extending transversely between the cladding and the vapor collection pipe, the vapor being It is sealably connected to the collection pipe to provide a primary sealed space between the cladding and the vapor collection pipe, the primary sealed space communicating with the primary thermal insulation barrier, and the cladding between the upper annular plate and the secondary sealing membrane. a sheath having a shape arranged such that an outer diameter of the sheath tapers toward the secondary sealing membrane between the upper annular plate and the secondary sealing membrane at ; and

- a primary exhaust device adapted to discharge fluid from the primary thermal insulation barrier, the primary exhaust device comprising a pipe sealably connected to the upper annular plate and communicating with the primary thermal insulation barrier through a primary sealed space; car exhaust system

It provides a sealed and insulated tank comprising a.

Thanks to the specific shape of the sheathing, therefore, the cross-section of the pipes of the primary exhaust system sealably connected to the upper annular plate and the bulk of the sheathing in the vicinity of the secondary sealing membrane are independent of each other. Therefore, the cross section of the pipe of the primary exhaust system can be optimized to obtain a sufficient discharge flow rate, but this optimization of the cross section does not lead to an increase in the cross section of the sheath near the secondary sealing membrane, as a result of which the secondary sealing membrane does not impair the mechanical properties of

According to embodiments, such a sealed and insulated tank for storing fluid includes one or more of the following features.

According to one embodiment, the sheath has a shape arranged so that the outer diameter of the sheath tapers between the upper annular plate 20 and the secondary sealing membrane towards the secondary sealing membrane.

According to one embodiment, the cladding has an inner cross-section greater than the inner cross-section of the cladding near its sealed connection to the secondary sealing membrane, along a plane perpendicular to the longitudinal direction of the gas dome structure near the upper annular plate. .

According to one embodiment, the cladding has a frustoconical portion between the upper annular plate and the secondary sealing membrane that tapers towards the secondary sealing membrane.

According to one embodiment, the primary sealed space communicates with the thermal insulation barrier through a passage provided between the vapor collection pipe and the secondary sealing membrane and/or through the secondary sealing membrane.

According to one embodiment, the gas dome structure includes an insulating lining disposed in a primary sealed space provided between the cladding and the vapor collection pipe, and a passage provided in the insulating lining connects the pipe to the primary insulating barrier.

According to one embodiment, the secondary sealing membrane has an opening through which the vapor collection pipe passes, the opening having a larger diameter than the circumferential wall of the vapor collection pipe so as to form a gap between the circumferential wall of the vapor collection pipe and the secondary sealing membrane. An annular passage connecting the primary sealed space and the primary thermal insulation barrier is provided.

According to one embodiment, the cladding has a lower end welded to the lower annular plate, which is welded to the secondary sealing membrane, through which the vapor collection pipe passes and has a larger diameter than the circumferential wall of the vapor collection pipe. and an opening connecting the primary sealed space and the primary thermal insulation barrier.

According to one embodiment, a passage is provided in the insulating lining so that from the pipe of the primary exhaust system towards the annular passage the passage converges towards the vapor collection pipe. This allows the pipe of the primary exhaust system to be positioned far enough away from the vapor collection pipe to allow the passage of welding tools.

According to one embodiment, the passage is provided in the insulating lining such that its cross-section remains at all points greater than or equal to the cross-section of the pipe of the primary exhaust system.

According to one embodiment, the passage is formed by a series of cylindrical cavities cut into the insulating lining and communicating with one another.

According to one embodiment, the upper annular plane is positioned above the support structure.

According to one embodiment, the pipe of the primary exhaust device is welded around an opening provided in the upper annular plate.

According to one embodiment, the pipe of the primary exhaust device is connected to a valve which can be opened when the pressure of the primary thermal insulation barrier is greater than the threshold pressure.

According to one embodiment, the secondary sealing membrane comprises a plurality of corrugated metal sheets sealably welded to each other and each comprising at least two orthogonal corrugations. The aforementioned gas dome structure can be limited in number of corrugations interrupted by the gas dome structure by limiting the size of the gas dome structure in the vicinity of the secondary sealing membrane, especially when the secondary sealing membrane is a corrugated membrane. Advantageously, this allows the loss in elasticity of the secondary sealing membrane near the passage of the gas dome structure to be limited. This makes it possible to maintain homogeneity in the working process of the pleats, in particular to limit constraints in the sealed connection between the sheath and the secondary sealing membrane.

According to one embodiment, the gas dome structure has a central axis with two guide lines of two mutually orthogonal central corrugations of the secondary sealing membrane intersecting at the central axis of the gas dome structure.

According to one embodiment, each of the two central pleats is disposed between two adjacent pleats, and the two adjacent pleats of each of the two central pleats form a peripheral region in which the sheath is to the secondary sealing membrane. Sealably connected.

According to one embodiment, the gas dome structure includes a vapor collection pipe and an outer shaft disposed around the cladding and sealably welded to the support structure.

According to one embodiment, an annular passage is provided between the support structure and the cladding, allowing fluid present in the secondary sealed barrier to circulate towards the secondary sealed space provided between the outer shaft and the vapor collection pipe.

Such tanks may form part of an onshore storage installation, for example for storing LNG, or floating, offshore or pelagic structures, in particular LNG transport vessels, floating storage and regas units (FSRUs), offshore floating It can be installed in a manufacturing and storage unit (FPSO).

According to one embodiment, a vessel comprises a double hull and the aforementioned tank disposed on the double hull, the double hull comprising an inner hull forming a supporting structure of the tank.

According to one embodiment, the present invention also provides a method for loading or unloading such a vessel, wherein fluid is suspended via insulated pipelines from a floating or onshore storage facility to or from a vessel's tank. It is transported either to food or to an onshore storage facility.

According to one embodiment, the present invention also provides a conveying system for fluids, the system comprising insulated pipelines arranged to connect the aforementioned vessel, a tank mounted on the vessel's hull, to a floating or land storage facility. , and pumps for transferring fluid from the floating or land storage facility to the tank of the ship or from the tank of the ship to the floating or land storage facility via insulated pipelines.

The present invention will be better understood and its additional objects, details, features and advantages will become more apparent through the following description of a plurality of specific embodiments of the present invention, which are provided by way of non-limiting description only and with reference to the accompanying drawings. .
1 is a partial cross-sectional view of a sealed and insulated tank and gas dome structure.
Figure 2 is a cross-sectional view showing a detailed view of the lower portion of the gas dome of Figure 1;
Figure 3 shows the secondary sealing membrane in the region of the gas dome.
4 is a schematic cut-away view of a tank of an LNG transport ship and a terminal for loading/unloading the tank.

Referring to FIG. 1 , a partially sealed and insulated tank for storing liquefied gas such as liquefied natural gas (LNG) or liquefied petroleum gas (LPG) is shown. The tank is equipped with a gas dome structure 1 configured to form a vapor circulation channel between the inner space 2 of the tank and a vapor collector, not shown, located outside the tank.

The tank is arranged inside the double hull of the vessel comprising an outer hull (3) and an inner hull (4). The inner hull 4 forms the supporting structure of the tank. The tank overall has a polyhedral shape.

Each wall of the tank has a multi-layer structure, which includes a secondary thermal insulation barrier 5 laid against the inner hull 4 from the outside to the inside in the thickness direction of the tank, and two fixed to the secondary thermal insulation barrier 5. A primary sealing membrane (6), a primary thermal insulation barrier (7) placed against the secondary sealing membrane (6), and a primary sealing membrane (8) fixed to the primary thermal insulation barrier (7) and brought into contact with the fluid stored in the tank. ).

The secondary insulation barrier 5 includes a plurality of secondary insulation panels fixed to the inner hull 4 by resin beads (not shown) and/or studs (not shown) welded to the inner hull 4. include them According to one embodiment, each secondary insulation panel comprises a polymer foam layer sandwiched between two rigid outer and inner plates, for example made of polyurethane foam and made for example of plywood. Each outer rigid plate is equipped with metal plates for fixing the secondary sealing membrane 6 .

The secondary sealing membrane 6 includes a plurality of corrugated metal sheets. The corrugated metal sheets are arranged offset relative to the secondary thermal insulation barrier 5 so that each of the corrugated sheets extends jointly on four adjacent secondary thermal insulation panels. The corrugated metal sheets of the secondary sealing membrane 6 are lap welded together and also along their edges on the metal plates of the secondary thermal insulation barrier 5 . According to one embodiment, the corrugations of the secondary sealing membrane 5 protrude towards the outside of the tank, ie towards the inner hull 4 . The corrugations of the secondary sealing membrane are accommodated in grooves provided in the inner plate of the secondary thermal insulation panels.

The primary thermal insulation barrier 7 includes a plurality of primary thermal insulation panels. The primary insulation panels are fixed on studs protruding from the secondary insulation panels through the secondary sealing membrane 6 toward the inside of the tank. Primary insulation panels have a structure similar to their secondary insulation panels and comprise a polymer foam layer made of, for example, polyurethane foam and sandwiched between two rigid outer and inner panels, for example made of plywood. In addition, each outer rigid plate of the secondary insulation panels is equipped with metal plates for fixing the primary sealing membrane 8 .

The primary sealing membrane 8 is obtained by assembling a plurality of corrugated metal sheets. The corrugated metal sheets of the primary sealing membrane 8 are lap welded together and also welded along their edges on the metal plates of the primary thermal insulation barrier 7 . The pleats of the primary sealing membrane 8 protrude toward the inside of the tank.

As an example, such a tank is specifically disclosed in application WO 2016/166481 with its arrangement within a gas dome structure.

The gas dome structure 1 includes a cylinder-shaped outer shaft 9, which extends in a longitudinal direction oriented perpendicular to the upper wall of the tank. The outer shaft (9) is welded to a collar (41), which extends radially outward with respect to the longitudinal axis of the outer shaft (9) and attaches the outer shaft (9) to the outer hull (3). It is welded on the outer hull (3) to fix.

Further, the lower end of the outer shaft 9 is sealably welded to the inner hull 4 on the circumference of the circular opening 11 provided in the inner hull 4 .

The upper end of the outer shaft 9 is sealably closed by a detachable cover 12 . The cover 12 is secured to an annular assembly clamp 13 extending transversely to the length of the outer shaft 9 and radially extending outward thereof. The cover 12 is secured to the assembly clamp by means of a plurality of fastening components. A sealing gasket (not shown) is compressed between the cover 12 and the assembling clamp 13 and thus provides a seal between the outside and the inside of the outer shaft 9 .

The cover 12 has a central orifice 14 adapted to be connected to a vapor collector, not shown, capable of circulating the vapor towards a degasification mast, burner, vessel propulsion device and/or liquefaction device. In this liquefaction device, the vapor phase gas is re-liquefied and reintroduced into the tank as a liquid phase.

In addition, the gas dome structure 1 includes a vapor collection pipe 15 fixed inside the outer shaft 9 . The vapor collection pipe 15 is concentric with the outer shaft 9 and passes through the double hull by successively passing through the opening 10 provided in the outer hull 3 and the opening 11 provided in the inner hull 4, It passes. A vapor collection pipe 15 also passes through the upper wall of the tank. The vapor collection pipe 15 comprises a cylindrical perimeter wall sealably welded to the primary sealing membrane 8, thereby sealing the primary thermal insulation barrier 7 with respect to the interior space 2 of the tank. The vapor collection pipe 15 has a lower end leading to the inner space 2 of the tank. The vapor collection pipe 15 thus provides a vapor circulation channel between the inner space 2 of the tank and a vapor collector, not shown, which is disposed outside the tank and is located in a central orifice 14 provided in the cover 12. Connected.

In the illustrated embodiment, a deflector 16 is installed at the lower end of the vapor collection pipe 15 to prevent liquid gas from being generated in the vapor collection pipe 15. Arranged perpendicular to the longitudinal direction, the cylindrical circumferential wall of the vapor collection pipe 15 has openings 17 through which the vapor phase present in the internal space 2 of the tank can access the vapor collection pipe 15 includes

Also in the vapor collection pipe 15 is a filter 17, in this example disposed at its upper end, which creates a pressure drop and thus prevents gas, which is liquid, from passing through the vapor collection pipe 15 to the vapor collector. are also equipped

The gas dome structure 1 further comprises an annular heat insulating layer 18, which is evenly distributed over the outer extent of the vapor collection pipe 15.

The gas dome structure 1 also includes a sheath 19 detailed in FIG. 2 , which is concentric with the vapor collection pipe 15 and runs radially between the vapor collection pipe 15 and the outer shaft 9 . are placed

The upper end of sheath 19 is sealably welded to upper annular plate 20 . The upper annular plate 20 surrounds the vapor collection pipe 15 and is sealably welded to the vapor collection pipe 15 . The upper annular plate 20 is disposed above the inner hull 4 and thus extends into the space between the inner hull 4 and the outer hull 3 of the double hull. In the illustrated embodiment, the upper annular plate 20 supports an annular insulating layer 18, which is optionally attached to the upper annular plate 20.

In addition, the sheath 19 is sealably connected to the secondary sealing membrane 6 . Thus, a primary sealed space 22 is provided between the sheath 19 and the vapor collection pipe 915. For this purpose, a lower annular plate 21 extending in a plane perpendicular to the longitudinal direction of the gas dome structure 1 is sealably welded to the secondary sealing membrane 6 . Further, the lower annular plate 21 is welded to the tubular part 23, which protrudes toward the outside of the tank, into which the lower end of the sheath 19 is fitted, the lower end of the sheath 19 being tubular. It is sealably welded to part 23 .

The lower annular plate 21 has a circular opening 24 with a larger diameter than the vapor collection pipe 15 through which the vapor collection pipe 15 passes. In addition, the secondary sealing membrane 6 is not welded to the circumferential wall of the vapor collection pipe 15, and also has a circular opening 35 whose diameter is larger than that of the vapor collection pipe 15. Thus, a circular passage 25 is provided around the vapor collection pipe 15, and a primary sealed space where the fluid present in the primary heat insulation barrier 78 is provided between the sheath 19 and the vapor collection pipe 15. It makes it possible to cycle towards (22).

The sheath 19 comprises a frusto-conical section 43 whose diameter decreases from the outside to the inside of the tank between the lower annular plate 21 and the upper annular plate 22. In other words, the sheath 19 has an inner diameter larger than its inner diameter at the upper annular plate 22 than that at the lower annular plate 21 .

An insulating lining 26 made of a polymer foam, for example polyurethane foam, is placed between the primary sealed space 22, i.e., the sheath 19 and the vapor collection pipe 15.

In addition, the gas dome structure 1 includes a primary exhaust device adapted to protect the primary sealing membrane 8 against overpressure likely to occur in the primary thermal insulation barrier 7 . This primary evacuation device is particularly useful for evacuating vapors that tend to form inside the primary thermal insulation barrier 7 in case of leakage of liquefied gas through the primary sealing membrane 8 .

The primary exhaust device comprises a pipe (27) that passes through the outer shaft (9) and follows the vapor collection pipe (9) inside the annular insulation layer (18) until it reaches the upper annular plate (20). . In the illustrated embodiment, the pipe 27 includes a coiled region that allows for thermal expansion and contraction of the pipe 27 .

The diameter of the pipe 27 is greater than 5 cm and is preferably greater than or equal to 7.5 cm to allow for a sufficient discharge flow rate.

The pipe 27 is sealably connected to the upper annular plate 20, for example by welding. For this purpose, in the illustrated embodiment, the upper annular plate 20 has an opening into which the end of the pipe 27 is inserted, and a weld is made between the pipe 27 and the circumference of this opening. Due to the flared shape of the sheath 19, the upper annular plate 20 is larger in the direction transverse to the longitudinal direction of the gas dome structure 1, which enables the cross section of the pipe 27 to be increased, while Provide sufficient clearance between the vapor collection pipe 15 and the pipe 27 to allow the passage of welding tools.

The pipe 27 is connected to a valve not shown, which is closed in the default state and opens when the pressure in the primary thermal insulation barrier 7 exceeds a predetermined threshold pressure.

Furthermore, according to one embodiment, the device also comprises a primary inert device allowing an inert gas such as nitrogen to be circulated within the primary thermal insulation barrier 7 . For this purpose, the gas dome structure 1 is equipped with a pipe 30, which passes through the outer shaft 9 and within the annular insulating layer 18 until it reaches the upper annular plate 20. In parallel with the vapor collection pipe (15). In the illustrated embodiment, the pipe 30 also includes a coiled region that allows for thermal expansion and contraction of the pipe 30 .

The pipe 30 is sealably connected to the upper annular plate 20, for example by welding. The end of the pipe 30 passes through an opening provided in the upper annular plate 20 and is welded around the opening. Further, the insulating lining 26 is provided with a passage 31 provided facing the pipe 30 and an annular passage 25 provided around the vapor collection pipe 15 . The pipe 30 is connected to an inert gas reservoir, not shown, and the device includes another pipe, not shown, which is connected to the inert gas reservoir, for example in the vicinity of the liquid dome structure, and which is connected to the primary thermal insulation barrier 7. Leading to the inside, it creates an inert gas circulation circuit capable of circulating the inert gas inside the primary thermal insulation barrier (7).

In addition, as shown in FIG. 2, the cladding 19 is not welded to the inner hull of the double hull (4), so that between the cladding 19 and the inner hull 4, the secondary insulation barrier 5 exists. An annular passage 32 is provided to allow fluid to circulate towards the secondary sealed space 33 shown in FIG. A secondary sealed space 33 is provided radially between the annular heat insulating layer 18 and the outer shaft 9, and is defined by an annular ring 42 at the upper part of the gas dome structure 1, which An annular ring sealably connects the outer shaft (9) to the vapor collection pipe (15).

According to one embodiment, two other pipes, not shown, pass sealably through the outer shaft 9 to lead to the secondary sealed space 33 . One of these pipes forms part of a secondary exhaust system to protect the secondary sealing membrane 6 from overpressure likely to occur within the secondary thermal insulation barrier 5 . For this purpose, the pipe is connected to a valve which is closed in the basic state and which opens when the pressure inside the secondary thermal insulation barrier 5 exceeds a predetermined threshold. The other pipe forms part of a secondary inert device which allows the inert gas to circulate within the secondary thermal insulation barrier (5).

4 shows the structure of the secondary sealing membrane 6 in the region of the gas dome structure 1 . The secondary sealing membrane 6 includes a secondary square-shaped metal closing plate 34 . A circular opening 35 through which the vapor collection pipe 15 passes, not shown in FIG. 4 , is provided in the secondary closure plate 34 . The two corrugated metal sheets 36, 37 disposed on both sides of the secondary closure plate 34 are cut to form an opening slightly smaller than the secondary closure plate 34. The two corrugated metal sheets 36 , 37 are sealably lap welded onto the secondary closure plate 34 .

The central axis of the gas dome structure 1 is centered at a position corresponding to the intersection between the guide lines of the two orthogonal corrugations 38 and 39 . These two corrugations 38 , 39 are thus interrupted at the secondary closure plate 34 . For this purpose, the corrugations 38 and 39 are sealably closed with end pieces 40 . Other adjacent corrugations pass through both sides of the gas dome structure uninterrupted.

The lower annular plate 21 is welded to the closure plate 34 in its central region defined by corrugations. It is understood that by defining the diameter of the lower part of the sheath 19 and thus the diameter of the lower annular plate 21 , it is possible to interrupt only the two corrugations 38 , 39 of the secondary sealing membrane 6 . However, this enables the loss of elasticity of the secondary sealing membrane 4 in the vicinity of the passage of the gas dome structure 1 to be limited.

The technology for sealed and insulated tanks described above can be used in various types of storage, such as LNG storage on land installations or floating structures such as LNG transport vessels.

Referring to FIG. 4 , a cutaway view of an LNG transport vessel 70 shows a sealed and insulated tank 71 having an overall prismatic shape mounted on the double hull 72 of the vessel. The wall of the tank 71 has a primary sealing barrier brought into contact with the LNG contained in the tank, a secondary sealing barrier disposed between the primary sealing barrier and the double hull 72 of the ship, and a primary sealing barrier and secondary sealing. It includes two thermal insulation barriers disposed between the barriers and between the secondary sealing barrier and the double hull 72, respectively.

In a manner known per se, the loading/unloading pipelines 73 arranged on the upper deck of the vessel are connected to the shore or harbor by suitable connectors to transfer the LNG cargo to and from the tank 71. can be connected to a terminal.

FIG. 4 shows an example of a shore terminal comprising a loading and unloading station 75 , an underwater pipe 76 and an onshore installation 77 . The loading and unloading station 75 is a fixed offshore installation comprising a movable arm 74 and a turret 78 supporting the movable arm 74 . The movable arm 74 supports a bundle of insulated flexible hoses 79 which can be connected to the loading/unloading pipelines 73. The orientable movable arm 74 is suitable for all types of LNG carriers. A connecting pipe (not shown) extends into the turret 78 . The loading and unloading station 75 enables the LNG carrier 70 to be loaded from and unloaded to the shore installation 77, which has liquefied gas storage tanks 80 and submersible pipes. and connecting pipes 81 connected by means of 76 to the loading or unloading station 75. The submersible pipe 76 allows liquefied gas to be transferred between the loading or unloading station 75 and the shore installation 77 over a considerable distance, for example 5 km, which allows the LNG transport vessel 70 to perform loading and unloading operations. In the process, it allows you to stay at a considerable distance from the shore.

Pumps aboard the vessel 70 and/or pumps aboard the shore installation 77 and/or pumps aboard the loading and unloading station 75 to create the pressure required to transport the liquefied gas. are used

Although the present invention has been described with reference to a plurality of specific embodiments, it is to be understood that the present invention is not limited thereto in any sense and includes all technical equivalents of the described means as well as combinations thereof, provided that they fall within the scope of the present invention. it is clear

The verb 'to include' or 'to accomplish' and its conjugations do not exclude the presence of elements or steps other than those recited in the claims.

In the claims, reference numbers placed in parentheses shall not be construed as limiting the claim.

Claims (16)

Sealed and insulated tank intended to store liquefied gas, in thickness direction, a secondary thermal insulation barrier (5) lying against the supporting structure (4), a secondary sealing membrane (6) lying against the secondary thermal insulation barrier (5) , an upper wall continuously provided with a primary thermal insulation barrier (7) lying against a secondary sealing membrane (6) and a primary sealing membrane (8) brought into contact with the liquefied gas contained in the tank, the tank comprising: Further comprising a gas dome structure 1, wherein the gas dome structure 1:
- a vapor collection pipe 15 adapted to extract vapors produced by evaporation of liquefied gas in the tank, which vapor collection pipe 15 passes through an opening 11 provided in the supporting structure 4, and which passes through the upper side of the tank Passing through the wall, the vapor collection pipe 15 comprises a peripheral wall sealably connected to the primary sealing membrane 8;
- a sheath (19) disposed around the vapor collection pipe (15), said sheath (19) having a lower end sealably connected to a secondary sealing membrane (6), said sheath (19) comprising the sheath (19) ) and the vapor collection pipe 15, the upper annular plate 20 extending transversely to the vapor collection pipe is sealably connected to the primary sealed space between the sheath 19 and the vapor collection pipe 15. 22, the primary sealed space 22 communicates with the primary thermal insulation barrier 7, and the sheath 19 is provided between the upper annular plate 20 and the secondary sealing membrane 6. a sheath 19 having a shape disposed so that the outer diameter of 19 tapers between the upper annular plate 20 and the secondary sealing membrane 6 towards the secondary sealing membrane 6; and
- a primary exhaust device adapted to discharge fluid from the primary thermal insulation barrier (7), the primary exhaust device being sealably connected to the upper annular plate (20) and via the primary thermally sealed space (22) to the primary thermal insulation device; Primary exhaust device comprising a pipe 27 communicating with the barrier 7
A sealed and insulated tank comprising a. 2. The sheath (19) is sealed and thermally insulated with a frustoconical portion (43) tapering towards the secondary sealing membrane (6), between the upper annular plate (20) and the secondary sealing membrane (6). old tank. 3. The gas dome structure (1) according to claim 1 or 2, comprising a heat insulating lining (26) disposed in the primary sealed space provided between the cladding (19) and the vapor collection pipe (15), A sealed and insulated tank in which a passage (29) provided at (26) connects the pipe (27) to the primary thermal insulation barrier (7). 3. The method according to claim 1 or 2, wherein the secondary sealing membrane (6) has an opening (24) through which the vapor collection pipe (15) passes, said opening (24) around the circumference of the vapor collection pipe (15). An annular passage 25 having a larger diameter than the wall and connecting the primary sealed space 22 and the primary insulation barrier 7 between the peripheral wall of the vapor collection pipe 15 and the secondary sealing membrane 6 is formed. Sealed and insulated tanks provided. 5. The method of claim 4, wherein the sheath (19) has a lower end welded to the lower annular plate (21), which is welded to the secondary sealing membrane (6), and the vapor collection pipe (15) ) passes through and has a larger diameter than the circumferential wall of the vapor collection pipe 15 and has an opening 24 connecting the primary sealed space 22 and the primary thermal insulation barrier 7. . According to claim 4,
The gas dome structure 1 is provided with a heat insulating lining 26 disposed in the primary sealed space provided between the sheath 19 and the vapor collection pipe 15, the heat insulating lining 26, and the pipe 27 as described above. comprising a passage (29) connecting to the primary thermal insulation barrier (7), said passage (29) from the pipe (27) of the primary exhaust device towards the annular passage (25), said passage (29) collecting vapor A sealed and insulated tank provided with an insulating lining (26) so as to converge towards the pipe (15). 3. The sealed and insulated tank according to claim 1 or 2, wherein the upper annular plate (20) is positioned above the supporting structure (4). 3. The sealed and insulated tank according to claim 1 or 2, wherein the pipe (27) of the primary exhaust system is welded around an opening provided in the upper annular plate (20). 3. The sealed and insulated tank according to claim 1 or 2, wherein the pipe (27) of the primary exhaust system is connected to a valve which can be opened when the pressure in the primary thermal insulation barrier (7) is greater than the threshold pressure. 3. The secondary sealing membrane (6) according to claim 1 or 2, comprising a plurality of corrugated metal sheets (34, 36, 37) which are sealably welded to each other and each comprise at least two orthogonal corrugations. Sealed and insulated tank. 11. The gas dome structure (1) according to claim 10, wherein the gas dome structure (1) has two guides of two mutually orthogonal central corrugations (38, 39) of the secondary sealing membrane (6) intersecting at the central axis of the gas dome structure (1). A sealed and insulated tank having a central axis with lines. 12. The method of claim 11, wherein each of the two central pleats (38, 39) is disposed between two adjacent pleats, and the two adjacent pleats of each of the two central pleats (38, 39) form a peripheral area; , a sealed and insulated tank in which the sheathing (19) is sealably connected to the secondary sealing membrane (6). The gas dome structure (1) according to claim 1 or 2, comprising an outer shaft (9) arranged around the vapor collection pipe (15) and the sheath (19) and sealably welded to the support structure (4). A sealed and insulated tank containing A vessel (70) for transporting a fluid, said vessel comprising a double hull (72) and a tank (71) according to claim 1 or 2 arranged in the double hull, the double hull forming a support structure for the tank. Vessel containing the inner hull. A method for loading or unloading a vessel (70) according to claim 14, wherein the fluid is transferred from a floating or onshore storage facility (77) to the vessel's tank (71) via insulated pipelines (73, 79, 76, 81). or from a vessel's tank (71) to a floating or land storage facility (77). A conveying system for a fluid, the system comprising insulated pipelines (73) arranged to connect a vessel (70) of claim 14, a tank (71) mounted on the hull of the vessel to a floating or land storage facility (77), 79, 76, 81), and a pump for transferring fluid through insulated pipelines from a floating or land storage facility to a vessel's tank, or from a vessel's tank to a floating or land storage facility.

Images