Dome structure for a closed heat-insulated tank

Abstract

The present invention relates to a dome structure for a hermetically insulated tank, the dome structure having a horizontal lid and a side dome wall including a hermetic membrane with at least one corrugated portion, the dome structure comprising at least one heat insulation block anchored to the lower surface of the lid, the heat insulation block and the corrugated portion being spaced apart from each other by a first distance in a projection on a horizontal plane, a heat insulating linear portion including one or more linear elements, the heat insulating linear portion being adjacent to the side wall and positioned with respect to the lid and disposed between the heat insulation block and the side wall, each of the one linear element or the plurality of linear elements having a thickness less than the first distance in a direction perpendicular to the side dome wall, and a holding plate anchored to the lower surface of the heat insulation block and extending at the lower surface of the heat insulating linear portion.

Description

Technical Field

[0001] The present invention relates to the field of hermetic insulated tanks for the storage and / or transportation of fluids such as cryogenic fluids. In particular, for the storage of liquefied natural gas (LNG) stored at atmospheric pressure at about -162°C, a hermetic and highly heat-insulating tank is employed.

Background Art

[0002] International Publication No. 2019 / 215414 discloses a liquefied gas storage facility including a support structure constituting a double hull of a ship and a hermetic insulated tank disposed within the support structure. This facility includes a dome structure that functions as a penetration point for a loading / unloading tower including pipes for loading the tank or unloading from the tank. This dome structure protrudes upward from an upper support wall. It includes a vertical support wall rising above the deck of the ship and a horizontal wall disposed at the top of the vertical support wall. The horizontal wall supports a lid including a metal lid wall and a heat insulating material fixed to the lower surface of the metal lid wall. Further, the vertical support wall of the dome structure is covered from the outside to the inside by a multi-layer structure including a secondary heat insulating barrier, a secondary hermetic membrane, a primary hermetic membrane, a primary heat insulating barrier, and a primary hermetic membrane. The primary hermetic membrane includes a plurality of corrugated portions that impart elasticity to itself and protrude toward the inside of the dome structure.

[0003] As described with reference to FIGS. 15 and 16 of the above-mentioned document, when the metal lid wall is attached to and welded to the other wall of the dome structure and the loading / unloading tower is fixed to the metal lid, the heat insulating element is fixed to the central portion of the lid. At this stage, the peripheral portion of the metal lid wall is not covered with the heat insulating element. In a subsequent step, the edge heat insulating element is positioned relative to the peripheral portion of the metal lid wall. However, at the upper part of the vertical wall of the dome structure, the presence of the corrugated portion of the primary sealing membrane protruding inward prevents the positioning of the edge heat insulating element relative to the peripheral portion of the metal lid wall in the space formed between one of the primary sealing membranes of one of the dome vertical walls and one of the heat insulating elements fixed to the central portion of the metal lid wall. SUMMARY OF THE INVENTION

[0004] One idea underlying the present invention is to propose a dome structure that facilitates the arrangement of heat insulating materials for the lid of the dome structure.

[0005] According to one embodiment, the present invention provides a dome structure for a hermetically insulated tank, the dome structure being intended to project vertically from the ceiling wall of the tank and defining a passage intended to pass at least one pipe for loading liquefied gas into the tank or unloading the liquefied gas from the tank, the plurality of side dome walls including a first side dome wall including a corrugated sealing membrane, the corrugated sealing membrane including at least one corrugated portion projecting in the direction of the passage, the dome structure including at least one heat insulation block anchored to the lower surface of the lid, the heat insulation block and the corrugated portion being spaced apart from each other by a first distance in a projection on a horizontal plane, a heat insulation linear portion including one or a plurality of linear elements, the heat insulation linear portion being adjacent to the first side wall, positioned with respect to the lid, and disposed between the heat insulation block and the first side wall, each of the one linear element or the plurality of linear elements having a thickness less than the first distance in a direction perpendicular to the first side dome wall or being compressible to be less than the first distance in the direction perpendicular to the first side dome wall, and a holding plate anchored to the lower surface of the heat insulation block and extending at the lower surface of the heat insulation linear portion.

[0006] With these features, the heat insulation of the dome-shaped structure is completed, and the heat insulation linear portion enables heat insulation at the edge of the corrugated sealing membrane. Further, with the above-described features of the heat insulation linear portion, the latter can be easily installed despite the presence of the corrugated portion in the sealing membrane.

[0007] According to some embodiments of the present invention, this type of dome structure can have one or more of the following features.

[0008] According to one embodiment, the holding plate is disposed at a distance from the sealing membrane.

[0009] Therefore, this type of configuration prevents abrasion between the holding plate and the corrugated sealing membrane, such abrasion leading to premature wear of the holding plate and the corrugated sealing membrane, and possibly being exacerbated by the effects of the heat shrinkage phenomenon and deformation of the support structure.

[0010] According to one embodiment, the distance between the holding plate and the sealing membrane is a value included between 5 mm and 25 mm.

[0011] According to a preferred embodiment, the distance between the holding plate and the sealing membrane is a value included between 10 mm and 20 mm.

[0012] More preferably, the target value of the distance between the holding plate and the sealing membrane is 15 mm.

[0013] Therefore, such a value of the distance enables reduction of the risk that the holding plate rubs on the surface of the sealing membrane.

[0014] According to one embodiment, the holding plate is made of wood.

[0015] According to one embodiment, the holding plate is provided with a notch through which a vertical corrugated portion passes.

[0016] According to a preferred embodiment, the holding plate is made of plywood.

[0017] In fact, wood, especially plywood, is a material with low thermal conductivity. Furthermore, in the case where the holding plate and the sealing membrane come into accidental contact, a wooden holding plate has less risk of scratching the sealing membrane than when the holding plate is made of other materials (for example, metal).

[0018] According to one embodiment, at least one heat-insulating linear element is made of one material selected from glass wool, rock wool, and polyester wadding.

[0019] Therefore, the linear element is made of a flexible and heat-insulating material.

[0020] Furthermore, such a material is compressible and thus can facilitate the insertion of one or more linear elements.

[0021] According to one embodiment, at least one heat-insulating linear element is composed of a heat-insulating polymer foam.

[0022] Therefore, the linear element is composed of a heat-insulating material that realizes the heat-insulating property of the dome structure.

[0023] According to one embodiment, the corrugated sealing membrane includes vertical corrugations, and the heat-insulating linear part includes a plurality of linear elements. Among these linear elements, one contact element is arranged with respect to the sealing membrane between two consecutive vertical corrugations.

[0024] According to one embodiment, the contact linear element has an angled end.

[0025] Therefore, the contact linear element can optimally conform to the corrugated shape of the corrugated sealing membrane, thereby providing optimal heat-insulating performance.

[0026] According to one embodiment, the contact linear element has the same thickness as the height of the corrugation in a direction perpendicular to the side dome wall.

[0027] According to one embodiment, the linear element includes a secondary linear element, and the secondary linear element extends into the space between the contact linear element and the heat-insulating block and has a dimension larger than the dimension of the contact linear element in the said direction in a direction perpendicular to the symmetry plane of the vertical corrugation.

[0028] Therefore, since the secondary linear element is common to a plurality of contact linear elements, the number of steps for fitting the heat-insulating linear part is reduced.

[0029] According to one embodiment, in the portion of the sealed membrane disposed above the holding plate, it is covered with a heat-insulating linear element.

[0030] Therefore, the dome structure can be completely insulated using the heat-insulating linear portion.

[0031] According to one embodiment, at least one heat-insulating block is anchored to the lid by means of studs, the studs pass completely through the at least one heat-insulating block, a bearing plate is positioned against the lower surface of the at least one heat-insulating block, and a nut is screwed onto the stud to hold the bearing plate.

[0032] Therefore, such a feature enables easy fixing of at least one heat-insulating block.

[0033] According to one embodiment, the present invention provides a sealed heat-insulating tank including the above-described dome structure.

[0034] According to one embodiment, the sealed heat-insulating tank has a loading / unloading tower including at least two vertical masts that pass through the lid and are fixed to each other by cross members, and each of the two vertical masts forms a pipe for loading the tank or unloading from the tank.

[0035] According to one embodiment, the present invention provides a ship for transporting a fluid, the ship including the above-described sealed heat-insulating tank.

[0036] According to one embodiment, the present invention provides a transportation system for fluids, comprising the above-described ship, a heat-insulating pipe arranged to connect the tank of the ship to a floating or onshore storage facility, and a pump for driving the fluid through the heat-insulating pipe from the floating or onshore storage facility to the tank of the ship or from the tank of the ship to the floating or onshore storage facility.

[0037] According to one embodiment, the present invention provides a method of assembling a dome structure for a hermetically sealed heat-insulated tank, the dome structure being intended to project vertically from the ceiling wall of the tank and defining a passage for at least one pipe for loading liquefied gas into or unloading liquefied gas from the tank, the plurality of side dome walls including a first side dome wall including a corrugated sealed membrane including at least one corrugated portion projecting in the direction of the passage, the dome structure including at least one heat-insulating block anchored to the lower surface of the lid, the heat-insulating block and the corrugated portion being spaced apart from each other by a first distance in a projection on a horizontal plane, the assembling method including arranging a heat-insulating linear portion including one or more linear elements between the heat-insulating block and the first side wall such that each of the one linear element or the plurality of linear elements has a thickness less than the first distance in a direction perpendicular to the first side dome wall or is compressed to be less than the first distance in the direction perpendicular to the first side dome wall, and anchoring a holding plate extending below the heat-insulating linear portion to the lower surface of the heat-insulating block to hold the heat-insulating linear portion.

[0038] According to one embodiment, in the assembling method, the at least one linear element is vertically inserted into the space between the corrugated sealed membrane and the heat-insulating block and then moved to contact the corrugated sealed membrane.

[0039] According to one embodiment, in the assembling method, the at least one heat insulation block is pre-fixed to the lid by means of studs, the studs pass completely through the at least one heat insulation block, a bearing plate is positioned against the lower surface of the at least one heat insulation block, and nuts are screwed onto the studs to hold the bearing plate.

[0040] According to one embodiment, in the assembling method, the linear element covers a part of the corrugated sealing membrane located above the holding plate.

[0041] According to one embodiment, the method further includes steps of arranging the contact linear element between two consecutive vertical corrugated portions, the contact linear element having the same height as the corrugation height, and arranging the secondary linear element to occupy a gap between the contact linear element and the at least one heat insulation block.

[0042] According to one embodiment, the secondary linear element has a dimension larger than the dimension of the contact linear element in the direction perpendicular to the symmetry plane of the corrugated portion in the direction.

[0043] According to one embodiment, in this assembling method, before being inserted into the space between the corrugated sealing membrane and the heat insulation block, the linear element is configured such that its ends are beveled.

[0044] According to one embodiment, the present invention further provides a method of loading or unloading a ship as described above, wherein the fluid is guided through a heat insulation pipe from a floating or onshore storage facility to the tank of the ship or from the tank of the ship to the floating or onshore storage facility.

[0045] The present invention can be better understood in the following detailed description of some specific embodiments of the present invention given as non-limiting examples with reference to the accompanying drawings, and additional objects, details, features and advantages are more clearly shown.

Brief Description of the Drawings

[0046]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13

Figure 14

Figure 15

Figure 16

Figure 17

Mode for Carrying Out the Invention

[0047] Figure 1 shows the rear part of the support structure 1 intended to receive the wall of the hermetic heat - insulating tank. The support structure 1 is formed by the double hull of the ship. The support structure 1 usually has a polyhedral shape. The support structure 1 has a front wall 2 and a rear wall 3, which are octagonal here. In Figure 1, the front wall 2 is only partially shown so as to enable visual recognition of the internal space of the support structure 1. The front wall 2 and the rear wall 3 are the closing walls of the ship and extend laterally in the longitudinal direction of the ship. Also, the support structure 1 includes an upper wall 4, a lower wall 5, and side walls 6, 7, 8, 9, 10, 11. The upper wall 4, the lower wall 5, and the side walls 6, 7, 8, 9, 10, 11 extend in the longitudinal direction of the ship and connect the front wall 2 and the rear wall 3.

[0048] The upper wall 4 includes a rectangular parallelepiped - shaped space protruding upward in the vicinity of the rear wall 3 of the support structure 1 and is known as the fluid dome 12. The fluid dome 12 is partitioned by a front transverse wall 13 and a rear transverse wall 14, and two transverse walls 15, 16 that extend vertically and protrude upward from the upper wall 4. The fluid dome 12 further includes a horizontal lid not shown in Figure 1, and this lid is intended to cover the opening between the front wall 13, the rear wall 14, and the transverse walls 15, 16 of the fluid dome 12 in a sealing manner.

[0049] Referring to FIG. 2, the tank which is the object of the assembling method described below is a membrane tank having a multilayer structure. Also, as schematically shown in FIG. 2, each wall of the tank, from the outside to the inside, in the thickness direction of the wall, includes a secondary heat insulation barrier 44 including a heat insulation element leaning against the support structure 1, a secondary sealing membrane 18 anchored to the heat insulation element of the heat insulation barrier 44, a primary heat insulation barrier 19 including a heat insulation element leaning against the secondary sealing membrane 18, and a primary sealing membrane 20 anchored to the heat insulation element of the primary heat insulation barrier 19 and intended to be in contact with the fluid contained in the tank, and continuously includes them. This multilayer structure of the tank is arranged on each of the walls 4, 5, 6, 7, 8, 9, 10, 11 of the support structure 1. This multilayer structure also exists on the wall of the fluid dome 12, except in the case at the level of the lid.

[0050] For example, each wall of the tank may be, in particular, of the Mark III type as described in, for example, French Patent Application No. 2691520, or of the Mark V type as described in, for example, International Publication No. 14 / 057221.

[0051] Each wall of the tank is anchored to the corresponding wall in the support structure 1, and as it progresses from the outside to the inside of the tank, that is, the heat insulation element of the secondary heat insulation barrier 44 is anchored to the corresponding wall of the support structure 1, the secondary sealing membrane 18 is anchored to the heat insulation element of the secondary heat insulation barrier 44, the heat insulation element of the primary heat insulation barrier 19 is anchored to the support structure 1 via the heat insulation element of the secondary heat insulation barrier 44 or the secondary sealing membrane 18, and the primary sealing membrane 20 is anchored to the heat insulation element of the primary heat insulation barrier 19.

[0052] Furthermore, the tank includes a loading / unloading tower as shown in FIGS. 3 and 4, and in particular enables loading of goods into the tank before transportation and / or unloading of goods after transportation. The loading / unloading tower 21 is installed near the rear wall 3 of the support structure 1. This is because when unloading goods, the ship tilts towards the rear, so the amount of goods that can be loaded and unloaded via the loading / unloading tower 21 can be optimized.

[0053] The loading / unloading tower 21 is suspended from the upper wall 4 of the support structure 1, and more specifically from the lid of the fluid dome 12. The loading / unloading tower 21 extends substantially over the entire height of the tank. The loading / unloading tower 21 supports one or more pumps at its lower end for loading and unloading goods.

[0054] It can be verified that the loading / unloading tower 21 has a tripod structure, that is, it includes three vertical masts 22, 23, 24 fixed to each other by cross members 25. Each of the masts 22, 23, 24 is hollow and passes through the lid of the fluid dome 12. Thus, each of the masts 22, 23, 24 forms either a loading / unloading line that enables loading fluid into the tank or unloading fluid from the tank, or a standby well that enables lowering a backup pump and making the unloading line usable in case other unloading pumps fail. In one embodiment, two masts 22, 23 are shown, each associated with unloading pumps 26, 27 fixed to the lower end of the loading / unloading tower 21 to form a line for unloading from the tank, and the third mast 24 forms a standby well. In this type of embodiment, the loading / unloading tower 21 carries one or more loading lines (not shown) that do not form one of the tripod-structured masts 22, 23, 24.

[0055] The method of attaching the heat insulation material to the lid 17 of the dome structure 12 will be described with reference to FIGS. 5 to 8.

[0056] In the first step, schematically shown in FIG. 5, the dome structure 12 is in a preliminary state where the central heat insulation block 30 is anchored to the lid 17. The side wall 15 is covered by the sealing membrane 32. The mounting member 36 is fixed to the lid 17 and is placed vertically.

[0057] The first step consists of arranging the edge heat insulation block 31 with respect to the central heat insulation block 30 and the sealing membrane 32. The edge heat insulation block 31 has dimensions such that it can be vertically inserted between the central heat insulation block 30 and the sealing membrane 32 without contacting the corrugated portion 33, and the corrugated portion 33 extends in a direction perpendicular to the plane of FIG. 5.

[0058] The edge heat insulation block 31 is fixed to the lid by the mounting member 36, and the mounting member 36 is intended to pass completely through the edge heat insulation block 31.

[0059] The edge heat insulation block 31 and the central heat insulation block 30 can be made of a heat insulating polymer foam, such as polyurethane foam, or wood with a thinner thickness, preferably plywood.

[0060] Referring to FIG. 6, after the first mounting step, the edge heat insulation block 31 has a mounting member 36 that penetrates so as to protrude from the lower surface of the edge heat insulation block 31. The mounting member 36 is preferably located at the center of the edge heat insulation block 31.

[0061] The edge heat insulation block 31 is arranged with respect to the central heat insulation block 30, leaving a gap 34 between the edge heat insulation block 31 and the sealing membrane 32. Further, the height of the edge heat insulation block 31 in the direction perpendicular to the lid 17 is the same as the height of the central heat insulation block 30. As depicted in this FIG. 6, the edge heat insulation block 31 and the corrugated portion 33 having the highest height are separated from each other by a first dimension corresponding to the reference d1 in FIG. 6 in the projection in the horizontal plane.

[0062] Referring to FIGS. 6 and 7, the second mounting step is shown. The second mounting step consists of inserting a heat-insulating linear part 40 between the edge heat-insulating block 31 and the sealing membrane 32, and the heat-insulating linear part 40 is inserted through the gap 34. The heat-insulating linear part 40 is inserted in such a way as to completely fill the gap 34.

[0063] In one embodiment, the heat-insulating linear part 30 includes a linear element having a dimension d2 greater than the dimension d1 in a direction perpendicular to the side wall 15. In this case, the heat-insulating linear part 40 is made of a compressible material, and the heat-insulating linear part 40 is compressed in such a manner that it can later occupy all of the gap 34.

[0064] In an alternative embodiment, the heat-insulating linear part 40 may be equally composed of a plurality of linear elements, and each linear element has a dimension d2 less than d1 in a free state or a compressed state. Therefore, these linear elements can be inserted sequentially and then juxtaposed in the gap.

[0065] In this case, these linear elements are inserted vertically into the gap and then moved horizontally until they contact the sealing membrane 32 or until they contact a preceding linear element pre-arranged with respect to the sealing membrane 32. These sealing elements, when having a dimension d2 less than d1, although not essential, may be compressed to pass through the gap.

[0066] The heat-insulating linear part 40 is composed of heat-insulating elements such as glass wool, rock wool, polyester wadding, or flexible foam. The heat-insulating linear part 40 can similarly include a polymer foam, such as polyurethane foam.

[0067] Furthermore, it is possible to combine different types of materials and to have heterogeneous linear elements consisting of two different elements.

[0068] Referring to FIGS. 7 and 8, the third mounting step consists of placing the holding plate 35 under the heat-insulating linear part 40 in such a way as to hold the holding plate 35 in a predetermined position. The holding plate 35 is made of wood, preferably plywood.

[0069] The holding plate 35 is arranged so as to partially overlap the lower surface of the edge heat-insulating block 31 and is anchored to the lower surface. The holding plate 35 extends below the heat-insulating linear part 40 up to the sealing membrane 32 (without being in direct contact with the sealing membrane 32) so as not to let the heat-insulating linear part 40 pass through.

[0070] The holding plate 35 can be, for example, adhered or screwed to the edge heat-insulating block.

[0071] Referring to FIGS. 9 to 11, a part of the dome structure 12 is shown in perspective in a provisional state. The lid 17 is provided with regularly distributed mounting members 36 such as studs.

[0072] The central heat-insulating block 30 is arranged in contact with the lid 17 and is intended to be fixed thereto, for example, by adhering thereto or by means of an anchoring device (not shown).

[0073] The first side wall 15 is covered by the first sealing membrane 321. The second side wall 16 is covered by the second sealing membrane 322.

[0074] The first sealing membrane 321 and the second sealing membrane 322 include horizontal corrugated parts 33 extending parallel to the plane of the lid 17.

[0075] The first sealing membrane 321 and the second sealing membrane 322 further include vertical corrugated parts 39 perpendicular to the horizontal corrugated parts 33 and parallel to the direction perpendicular to the plane of the lid 17.

[0076] Referring to FIG. 10, the first edge heat insulation block 311 is disposed between the central heat insulation block 30 and the first sealing membrane 321. The second edge heat insulation block 312 is disposed between the central heat insulation block 30 and the second sealing membrane 322.

[0077] However, the first edge heat insulation block 311 and the second edge heat insulation block 312 do not directly contact the first sealing membrane 321 and the second sealing membrane 322, respectively.

[0078] The first edge heat insulation block 311 and the second edge heat insulation block 321 are fixed to the lid by attachment members 36, here pins. The attachment members 36 form a grid on the lid wall 17 and are arranged equidistant from each other. The attachment members 36 project from the surface of the lid wall 17. The attachment members 36 completely penetrate the edge heat insulation blocks 311, 321 and are held at the level of the lower surface of the heat insulation blocks. For this purpose, for example, a bearing plate is attached to the end of the attachment member 36, is disposed in contact with the lower surface of the heat insulation block, and is held in place by bolts.

[0079] Referring to FIGS. 11 to 15, the arrangement of the linear elements between the edge heat insulation block 31 and the sealing membrane 32 according to an embodiment is described. In the foregoing figures, the details of the corner region of the dome structure 12 are represented in a perspective view.

[0080] Referring to FIG. 11, the first contact linear element 41 is inserted into the gap 34 and then disposed relative to the sealing membrane 32. The first contact linear element 41 has a height in a direction perpendicular to the plane of the lid 17 such that the first contact linear element 41 occupies the space between the lid 17 and the edge horizontal corrugated portion 331, and the edge horizontal corrugated portion 331 is the horizontal corrugated portion closest to the lid 17.

[0081] The first contact linear element 41 further has dimensions such that it can be accommodated between two consecutive vertical corrugated portions 39 or between the edge of the dome structure 12 and the first vertical corrugated portion 39.

[0082] Finally, the thickness of the first contact linear element 41 in the direction perpendicular to the first side wall 15 is the same as or substantially the same as the height of the corrugated portion 33. However, in other embodiments, the contact linear element 41 can have a greater thickness, and in particular, when the contact linear element 41 is made of a compressible material, it can occupy all of the gap 34.

[0083] Referring to FIG. 12, a secondary linear element 42 is inserted between the contact linear element 41 and the edge heat insulation block 31. The secondary linear element 42 has a length greater than the length of the contact linear element 41. In fact, the secondary linear element 42, in contrast to the contact linear element 41, is not limited in length by the presence of the vertical corrugated portion 39.

[0084] Referring to FIGS. 13 and 14, the contact linear element 41 is disposed between each pair of consecutive horizontal corrugated portions 33. Further, the secondary linear element 42 has a length greater than that of the contact linear element 41 and can be common to a plurality of consecutive contact linear elements 41. According to a preferred embodiment, the contact element 41 has an inclined surface 43 with an inclination such that the contact linear element 41 is tangent to the corrugation of the sealing membrane 32 and the horizontal corrugated portion 33 has two curved sides.

[0085] The secondary linear element 42 is disposed with respect to the contact linear element 41 and is in a tangential direction with respect to the top of the horizontal corrugated portion 33.

[0086] Referring to FIG. 14, it can be seen that the linear elements can have different thicknesses for each dimension of the dome structure 12. In fact, when the sealing membrane includes corrugated portions having various heights, the tallest corrugated portion is the one oriented in the longitudinal direction of the ship, while the shortest corrugated portion is oriented in the transverse direction of the ship. This is the reason why, depending on the orientation of the side walls of the dome structure, the vertical corrugated portions 33 of the sealing membrane 32 can be the largest at the side walls (when oriented transversely) and the smallest at the adjacent side walls (when oriented vertically). FIG. 15 shows that the holding plate 35 is not in contact with the sealing membrane 32. In fact, the distance between the sealing membrane 32 and the holding plate 35 is between 5 mm and 25 mm. The existence of such a clearance can prevent the sealing membrane 32 and the holding plate 35 from coming into contact even if the tank undergoes high thermal deformation during use. Also, the holding plate 35 uniformly includes notches through which the vertical corrugated portions pass.

[0087] The adjustment affects at the level of the edge insulation block 31. In fact, depending on the required margin, the holding plate 35 may be fixed more or less closely to the sealing membrane 32. The holding plate 35 may be fixed by screws or adhesives.

[0088] Referring to FIG. 16, a more overall view of the corner area of the dome structure is represented. The linear elements are in contact with the edges of the insulation block 31 facing the sealing membrane 32.

[0089] According to the embodiment described herein, each linear element of the heat-insulating linear portion 40 occupies all of the area delimited by the sealing membrane 32, the edge insulation block 31, and two consecutive vertical corrugated portions 39.

[0090] The liquefied gas intended to be stored in the tank may in particular be liquefied natural gas (LNG), i.e. a gas mixture containing mainly methane together with one or more other hydrocarbons. The liquefied gas may equally well be hydrogen, ethane or liquefied petroleum gas (LPG), i.e. a mixture of hydrocarbons resulting from the refining of oil containing essentially propane and butane.

[0091] Referring to Figure 17, the cross-sectional view of the methane tanker ship 70 shows a hermetically insulated tank 71 of generally prismatic shape, which is mounted within the double hull 72 of the ship. The walls of the tank 71 include a primary hermetic barrier intended to be in contact with the LNG contained within the tank, a secondary hermetic barrier disposed between the primary hermetic barrier and the double hull 72 of the ship, and two insulation barriers respectively disposed between the primary hermetic barrier and the secondary hermetic barrier, and between the secondary hermetic barrier and the double hull 72.

[0092] In a method known per se, the loading / unloading pipe 73 disposed on the upper deck of the ship can be connected by suitable connectors to an offshore or port terminal in order to transfer LNG cargo to or from the tank 71.

[0093] FIG. 17 shows an example of an offshore terminal including a loading / unloading station 75, a subsea pipe 76, and onshore facilities 77. The loading / unloading station 75 is a fixed offshore facility including a movable arm 74 and a tower 78 supporting the movable arm 74. The movable arm 74 carries a bundle of insulated flexible tubes 79 connectable to the loading / unloading pipe 73. The orientable movable arm 74 adapts to the loading gauges of all methane tankers. A connecting pipe (not shown) extends inside the tower 78. The loading / unloading station 75 enables loading from the onshore facilities 77 to the methane tanker 70 or unloading from the methane tanker 70 to the onshore facilities 77. The onshore facilities 77 include a liquefied gas storage tank 80 and a connecting pipe 81 connected to the loading / unloading station 75 via the subsea pipe 76. The subsea pipe 76 enables the transfer of liquefied gas between the loading / unloading station 75 and the onshore facilities 77 over a large distance, for example 5 km, thereby allowing the methane tanker vessel 70 to stay at a large distance from the shore during loading and unloading operations.

[0094] The pumps mounted on the vessel 70 and / or the pumps installed in the onshore facilities 77 and / or the pumps installed in the loading / unloading station 75 are used to generate the pressure required to transfer the liquefied gas.

[0095] Although the present invention has been described in connection with several specific embodiments, the present invention is in no way limited thereto, and it is clear that all technical equivalents of the described means and combinations thereof are included within the scope of the present invention as long as the conditions are met.

[0096] The use of the terms “to comprise” or “to include” and their conjugations does not exclude the presence of other elements or other steps in addition to those recited in the claims.

[0097] In each claim, the reference signs in parentheses shall not be construed as constituting limitations of the claim.

Claims

1. A dome structure (12) for a sealed insulated tank, The aforementioned dome structure is A plurality of lateral dome walls (13, 14, 15, 16) are intended to project vertically from the ceiling wall of the tank and define a passage intended to allow at least one pipe (21) for loading liquefied gas into or unloading liquefied gas from the tank to pass through, Includes a horizontal cover (17) that closes the passage, The plurality of lateral dome walls are a first lateral dome wall including a corrugated sealing membrane (32), the corrugated sealing membrane including a first lateral dome wall including at least one corrugated portion (33) protruding in the direction of the passage, The aforementioned dome structure (12) is At least one heat insulating block (31) anchored to the lower surface of the lid, wherein the heat insulating block and the corrugated portion (33) are arranged such that, in a projection on a horizontal plane, they are spaced apart from each other by a first distance, A thermal insulation linear portion comprising one or more linear elements (40, 41, 42), wherein the thermal insulation linear portion is adjacent to the first lateral wall (15), positioned relative to the lid (17), and arranged between the thermal insulation block and the first lateral wall, and each of the one linear element (40, 41, 42) or the plurality of linear elements (40, 41, 42) has a thickness of less than the first distance in a direction perpendicular to the first lateral dome wall, or can be compressed to have a thickness of less than the first distance in the direction perpendicular to the first lateral dome wall, A dome structure (12) including a retaining plate (35) anchored to the lower surface of the heat insulating block and extending from the lower surface of the heat insulating linear portion.

2. The dome structure (12) according to claim 1, wherein the retaining plate (35) is positioned at a distance from the sealing membrane (32).

3. The dome structure (12) according to claim 2, wherein the distance between the retaining plate (35) and the sealing membrane (32) is between 5 millimeters and 25 millimeters.

4. The dome structure (12) according to claim 1 or claim 2, wherein the retaining plate (35) is made of wood.

5. The dome structure (12) according to claim 1 or 2, wherein at least one linear element (40, 41, 42) is made from one material selected from glass wool, rock wool, and polyester wadding.

6. The dome structure (12) according to claim 1 or 2, wherein the at least one linear element (40, 41, 42) is made of a thermal insulation polymer foam.

7. The dome structure (12) according to claim 1 or 2, wherein the corrugated sealing membrane (32) includes a plurality of vertical corrugated portions, and in the plurality of vertical corrugated portions, among the plurality of linear elements (40, 41, 42) included in the adiabatic linear portion, a contact element (41) is positioned between two consecutive vertical corrugated portions relative to the sealing membrane.

8. The at least one linear element (40, 41, 42) is made of a thermal insulation polymer foam, The dome structure (12) according to claim 7, wherein the contact linear element (41) has an oblique end (43).

9. The dome structure (12) according to claim 7, wherein the contact linear element (41) has a thickness equal to the corrugation height in a direction perpendicular to the lateral dome wall.

10. The linear elements (40, 41, 42) include a secondary linear element (42), The secondary linear element (42) extends into the space between the contact linear element (41) and the heat insulating block (31), and has dimensions larger than those of the contact linear element (41) in the direction perpendicular to the plane of symmetry of the vertical corrugated portion. The dome structure (12) according to claim 9.

11. The dome structure (12) according to claim 1 or 2, wherein the sealing membrane (32) is covered by a heat insulating linear element in the portion above the retaining plate (35).

12. The dome structure (12) according to claim 1 or 2, wherein at least one insulating block is anchored to the lid by means of a stud, the stud passes completely through the at least one insulating block, a bearing plate is positioned relative to the lower surface of the at least one insulating block, and a nut is screwed onto the stud to hold the bearing plate.

13. A sealed, insulated tank comprising the dome structure (12) according to claim 1 or claim 2.

14. A sealed insulated tank according to claim 13, comprising a loading / unloading tower (21) including at least two vertical masts passing through the lid and fixed to each other by a cross member, each of the two vertical masts forming a pipe for loading into or unloading from the tank.

15. A vessel for transporting fluids, having a sealed, insulated tank as described in claim 13.

16. A transport system for fluids, The vessel described in claim 15, An insulated pipe arranged to connect the tank of the vessel to a floating or land-based storage facility, A pump for driving fluid through the insulated pipe from the floating or land-based storage facility to the tank of the vessel, or from the tank of the vessel to the floating or land-based storage facility, A transportation system having

17. A method for assembling a dome structure (12) for a sealed insulated tank, the dome structure comprising a plurality of lateral dome walls intended to project vertically from the ceiling wall of the tank and defining a passage intended to allow at least one pipe to pass through for loading or unloading liquefied gas into or from the tank, and a horizontal lid closing the passage, wherein the plurality of lateral dome walls (13, 14, 15, 16) comprises a first lateral dome wall (15) including a corrugated sealing membrane (32), the corrugated sealing membrane including at least one corrugated portion (33) projecting in the direction of the passage, and the dome structure comprising at least one insulated block (31) anchored to the lower surface of the lid (17), the insulated block (31) and the corrugated portion (33) including at least one insulated block (31) spaced apart from each other at a first distance in a horizontal projection, The assembly method includes the steps of arranging a heat insulating linear portion, which includes one or more linear elements (40, 41, 42), between the heat insulating block (31) and the first lateral wall (15), such that each of the one linear element (40, 41, 42) or the plurality of linear elements (40, 41, 42) has a thickness less than the first distance in the direction perpendicular to the first lateral dome wall, or is compressed until it is less than the first distance in the direction perpendicular to the first lateral dome wall, A method for assembling a dome structure (12), comprising the step of anchoring a retaining plate (35) extending downward from the insulating linear portion to the lower surface of the insulating block so as to hold the insulating linear portion.

18. A method for assembling the dome structure (12) according to claim 17, comprising inserting the at least one linear element (40, 41, 42) vertically into the space between the corrugated sealing membrane (32) and the insulating block (31), and subsequently moving it to contact the corrugated sealing membrane (32).

19. A method for assembling a dome structure (12) according to claim 17 or 18, wherein the at least one heat insulating block (31) is pre-fixed to the lid (17) by means of a stud (36), the stud passes completely through the at least one heat insulating block (31), the bearing plate is positioned relative to the lower surface of the at least one heat insulating block, and a nut is screwed onto the stud to hold the bearing plate.

20. A method for assembling the dome structure (12) according to claim 17 or claim 18, wherein the linear elements (40, 41, 42) cover the corrugated sealed membrane (32).

21. The heat insulating linear portion has a plurality of linear elements (40, 41, 42) including a contact linear element (41) and a secondary linear element (42), The step of arranging the aforementioned insulating linear portion is: The contact linear element (41) is positioned between two consecutive vertical waveform sections, and the contact linear element has the same height as the waveform height. A method for assembling the dome structure (12) according to claim 20, comprising arranging the secondary linear element in the gap (34) between the contact linear element (41) and the at least one heat insulating block (31), wherein the secondary linear element has a dimension larger than that of the contact linear element in the direction perpendicular to the plane of symmetry of the corrugated portion.

22. A method for assembling the dome structure (12) according to claim 21, wherein the contact linear element (41) has an angled end (43) before being inserted into the space between the corrugated sealing membrane (32) and the insulating block (31).

23. A method for loading or unloading cargo onto or from a vessel according to claim 15, wherein the fluid is guided through an insulated pipe from a floating or onshore storage facility to the tank of the vessel, or from the tank of the vessel to the floating or onshore storage facility.

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