Modular unit for insulation of sealed thermally insulated tanks

Abstract

The present invention relates to a thermally insulating modular unit (3, 7) for insulating a sealed liquid storage tank, the modular unit (3, 7) comprising a thermally insulating filler, the thermally insulating filler comprising a powdered insulating material and at least one anion exchange compound, the powdered insulating material comprising a main component selected from fumed silica, silica aerogel, and mixtures thereof, the anion exchange compound being in the form of a powder mixed with the powdered insulating material, wherein the thermally insulating filler is not enclosed in an airtight box.

Description

Technical Field

[0001] The present invention relates to the field of sealed and thermally insulated tanks. More specifically, the present invention relates to the field of sealed and thermally insulated tanks comprising a metal sealing membrane and a thermally insulating modular block.

[0002] The invention also relates to thermally insulating modular blocks for insulating sealed tanks for storage and transportation of liquids. Background Art

[0003] Document WO-A-2019122757 discloses a thermal insulation barrier for a storage tank of cold liquids, the thermal insulation barrier comprising a plurality of juxtaposed insulation boxes. The box has a compartment and a powdered thermal insulation filler positioned in the compartment. The powdered filler presents an excellent compromise between low density and satisfactory thermal insulation performance, and is insensitive or only slightly sensitive to irreversible sedimentation phenomena after being immersed in the liquid stored in the tank. The powdered filler is generally selected from fumed silica, silica aerogel, and mixtures thereof.

[0004] These powdered fillers systematically contain small amounts of chlorine, i.e., about 10 parts per million (ppm) or more, due to their manufacturing process. Solid-state diffusion of the insulation in the form of dust, by being suspended in the air and moving with the movement of the air, or by movement caused by gravity or by all the accelerations experienced by the tanker, can lead to the chlorine coming into contact with the metal sealing membrane, for example, made of stainless steel or an alloy with a low thermal expansion coefficient, in particular an alloy of iron and nickel, such as Moisture may also carry chlorine present in the powdered filler, which then condenses and brings the chlorine into contact with the sealing membrane, causing pitting of the metal.

[0005] It is possible to get those powdered fillers without the chlorine element, but they cost much more.

[0006] Thus, in general, for any thermal insulation barrier comprising a gas-permeable envelope and comprising a powdered filler selected from fumed silica with a small amount of chlorine, silica aerogels, and mixtures thereof, corrosion phenomena of the external metal structure may be observed. Thus, depending on the technology used, this corrosion phenomenon, which weakens the sealing membrane, is very detrimental, in particular for sealed and thermally insulated tanks for the storage and / or transportation of liquids.

[0007] Therefore, it is generally recommended to solve this corrosion problem without compromising the thermal insulation performance qualities of the thermal insulation barrier, thereby developing a tank combined with a breathable thermal insulation barrier, the thermal insulation filling of which is based on fumed silica, silica aerogel, and mixtures thereof, and the external metal structure of the tank, which is sensitive to low concentrations of chlorine, is no longer corroded.

[0008] More specifically, it is proposed to improve the thermal insulation barrier for storage tanks for liquids, such as for example disclosed in FR 3 075 918, in order to overcome the drawbacks of corrosion observed on metal sealing membranes sensitive to low-density chlorine, such as for example an alloy of iron and nickel, more specifically known as An alloy of iron (64%) and nickel (36%).

[0009] Furthermore, the following documents are known in the field of thermal insulation or protection materials including fumed silica.

[0010] Document WO-A-2014184393 describes a composition comprising 40% to 93% of fumed silica or silica aerogel and 5% to 50% of a silica having a BET value of less than or equal to 100 m 2 / g of specific surface area. These particles are selected from a large number of products and are selected for scavenging gas molecules, thereby delaying the rise in internal pressure and thus maintaining optimal insulation properties. The size of the fumed silica particles is between 5nm and 50nm. Depending on the manufacturing process, the size of the silica aerogel particles is between 2nm and 50nm or between 50nm and 2000nm. It has a particle size determined by BET of less than or equal to 100m 2 Particles having a specific surface area of ​​less than or equal to 50 m / g may alternatively have a specific surface area of ​​less than or equal to 50 m 2 / g or alternatively has a specific surface area of ​​less than or equal to 30m 2 The composition is used to manufacture vacuum insulation panels (VIPs), which are used for the construction of new buildings and the insulation of existing buildings, such as insulation members in refrigeration equipment and for the insulation of pipes and / or machinery in industry.

[0011] Document KR-A-20130067712 discloses a flame retardant insulating material, which includes 35% to 99.5% by weight of fumed silica with a microporous structure, 0.3% to 25% by weight of a reinforcement, and 0.2% to 55% by weight of a heat-resistant filler. The reinforcement is selected from glass fiber, ceramic fiber, carbon fiber, quartz fiber, and a mixture thereof. The heat-resistant filler can be silicon carbide, zirconium silicate, graphite, metakaolin, titanium dioxide, pyrophyllite, vermiculite, perlite, calcium silicate, etc.

[0012] The document JP-A-201310449 relates to the field of processes for manufacturing vacuum insulating materials. The powder is sealed in a gas-impermeable packaging material under reduced pressure, in particular for use in buildings or freezers or refrigerators. It is stated that the powder is fumed silica, the average size of the main particles of which is between 5nm and 100nm, and the water content of the fumed silica is less than 1% by weight. In addition, the powder may contain gas and moisture adsorbing components such as synthetic zeolites, activated carbon, activated alumina, silica gel, dawsonite or hydrotalcite, and chemical adsorbent particles such as oxides and hydroxides of alkali metals and alkaline earth metals. Summary of the invention

[0013] Therefore, the overall goal of the present invention is to reduce or even eliminate the corrosion of the metal sealing film of the sealing tank, which is combined with a plurality of thermally insulating modular blocks, wherein the plurality of thermally insulating modular blocks include thermally insulating fillers mainly based on fumed silica, silica aerogel, and mixtures thereof.

[0014] More specifically, the present invention aims to reduce or even eliminate corrosion of the sealing membrane of a sealed and thermally insulated tank, which includes a plurality of gas-permeable modular blocks and is used to store a liquid selected from liquefied natural gas, liquefied petroleum gas, liquid methane, liquid ethane, liquid propane, liquid argon and liquid hydrogen.

[0015] The first subject matter according to the present invention relates to a thermally insulating modular block for insulating a sealed tank for storing liquids, the modular block comprising a thermally insulating filler, the thermally insulating filler comprising a powdered insulating material and at least one anion exchange compound, the powdered insulating material comprising a main component selected from fumed silica, silica aerogel, and mixtures thereof, the anion exchange compound being capable of capturing chloride anions in exchange for releasing at least one other anion, the anion exchange compound being in the form of a powder mixed with the powdered insulating material, the thermally insulating filler being not enclosed in an airtight enclosure.

[0016] The thermal insulation filler may also include fibers, such as glass fibers or carbon fibers. The thermal insulation filler may also contain infrared opacifiers such as SiC, TiO2, graphite or carbon black. The thermal insulation filler may also contain fillers such as perlite to limit the sedimentation of the thermal insulation filler, especially in the case of accidental infiltration of liquefied gas.

[0017] The following definitions allow a better understanding of the scope of the present disclosure.

[0018] The term "modular block" is understood to mean a self-supporting solid entity, such as a box or a rigid plate, which can be arranged as needed and in the desired number. The geometry can vary: cylindrical, parallelepiped or other.

[0019] The term "powdered insulating material" is understood to mean any composition in powder form that prevents heat loss. This powder may be packed in bulk, lightly pressed in a rigid container or flexible enclosure or pressed and densified in the form of a block or board sufficiently self-supporting to operate. This powder may also be packed in a flexible enclosure that is itself inserted into a rigid container to form a self-supporting board capable of operating. For example, depending on the envisaged application and the required mechanical properties, a powder may be packed in a powdered form at a rate of between 80 kg / m 3 With 500kg / m 3 The powder is packed with a density between

[0020] The term "anion exchange compound capable of trapping chloride anions" is understood to mean any chemical compound in powder form which exhibits OH - or CO3 2- The invention relates to a group and has the ability to exchange the anion included in the structure of the chemical compound with another chloride anion present in the thermal insulation filler. For example, clay, layered dihydrogen (LDH) compounds, synthetic hydrotalcite, cross-linked ion exchange polymers, and mixtures thereof can be mentioned. LDH compounds are solid compounds formed by stacks of sheets containing metal cations, and anionic entities and water molecules can be inserted between sheets. The structure of LDH compounds is based on the structure of brucite Mg (OH) 2, in which a part of divalent ions is randomly replaced by trivalent ions, thereby giving excess positive charge at the octahedral level. In order to ensure overall electrical neutrality, the excess charge is compensated by the negative charge of the anion inserted in the space between the sheets. The LDH used herein can include hydrated form and dehydrated form. Anion exchange compounds can also capture another ion halogen, such as fluorine, and the physical properties of the ion halogen are similar to those of chlorine.

[0021] The term "sealing film" is understood to mean a film or sheet of material comprising a metal or a metal alloy, which makes the tank sealed with respect to the liquid. For example, one may mention

[0022] The term "particles having an average apparent size" is understood to mean that the particles have a particle size distribution, thus defining the average value of this particle size distribution.

[0023] The term "proportion by weight" is understood to mean percentage by weight (%w) to indicate the proportion by weight of a component in the total mixture.

[0024] The term "fraction by volume" is understood to mean the volume of the component divided by the sum of the volumes of all components of the mixture.

[0025] The term "breathable envelope" is understood to mean a rigid or semi-rigid or flexible material defining an enclosed space. Examples of these breathable materials are, for example, wood, damping materials, textile materials, composite materials such as glass fiberboard, polymer fiberboard, plywood, compressed cardboard. Non-limiting examples of envelopes comprising a rigid frame can be found in particular in documents FR-A-2 867 831, WO-A-2013017773 and WO-A-2014020257.

[0026] In one embodiment, the thermally insulating modular block comprises a gas permeable envelope defining at least one compartment in which a thermally insulating filler is disposed.

[0027] In one embodiment, the powdered thermal insulation material includes little or no binder, such as a binder polymer.

[0028] In one embodiment, the proportion by weight of the binder used to condition the thermal insulation filler is less than 12%, for example between 0.3% and 12% of the thermal insulation filler. Larger amounts will lead to a deterioration in the performance quality of the thermal insulation of the modular blocks.

[0029] In one embodiment, the anion exchange compound is hydrated and includes water molecules.

[0030] In one embodiment, the anion exchange compound is selected from clay, layered dihydrogen (LDH) compounds, synthetic hydrotalcite (chemical composition is Mg6Al2(OH) 16 CO3.4H2O magnesium aluminate carbonate), such as ion exchanger III ( The product code 104767) contains the exchangeable anion OH - or CO3 2- Crosslinked ion exchange polymers, and mixtures thereof.

[0031] In one embodiment, the anion exchange compound exhibits a hydroxide ion (OH - ) and carbonate ions (CO3 2- ) group.

[0032] In one embodiment, the LDH compound has the formula [M II 1-x M III x (OH)2] x+ [A m-x / m .nH2O] x- , where M II and M III are the divalent and trivalent cations of the sheet, respectively, and A represents the anionic interlayer entity.

[0033] A may be any anion capable of exchanging with the chloride anions present in the thermally insulating filler. Preferably, A will not be a halogen anion or a sulphur anion.

[0034] In one embodiment, the anionic entity A of the LDH compound is selected from the group consisting of hydroxide ions (OH - ) and carbonate ions (CO3 2- ).

[0035] By way of example, different types of LDH minerals suitable according to the invention may be mentioned:

[0036] The molecular formula is Mg6Al2(OH) 16 Hydrotalcite of CO3.4H2O (rhombohedral structure)

[0037] The molecular formula is Mg6Al2(OH) 16 Hydromagnesium magnesia of CO3.4H2O (hexagonal structure)

[0038] The molecular formula is Mg6Al2(OH) 18 .4H2O hydroxymagnesia

[0039] The molecular formula is Mg6Fe2(OH) 16 CO3.4H2O pyroxenite (rhombohedral structure)

[0040] The molecular formula is Mg6Fe2(OH) 16 Hydromaficite (hexagonal structure) of CO3.4H2O

[0041] The molecular formula is Mg 10 Fe2(OH) 24 CO3.2H2O pyrocatecholite

[0042] The molecular formula is Mg6Cr2(OH) 16 CO3.4H2O magnesium chromite (rhombohedral structure)

[0043] The molecular formula is Mg6Cr2(OH) 16 Hydromagnesia chrome ore of CO3.4H2O (hexagonal structure)

[0044] The molecular formula is Ni6Cr2(OH) 16 Hydroaluminum Nickel Oxide in CO3.4H2O

[0045] The molecular formula is Ni6Fe2(OH) 16 CO3.4H2O meteorite nickel

[0046] The molecular formula is Mg6Mn2(OH) 16 Hydrocarbonite of CO3.4H2O

[0047] In one embodiment, the anion exchange compound will be selected from the group consisting of synthetic hydrotalcites (see Example 1), cross-linked polymers (see Example 2), and mixtures thereof.

[0048] According to one embodiment, the anion exchange compound is provided in the form of particles having an average apparent size between 1 μm and 50 μm, preferably between 1 μm and 25 μm and more advantageously between 1 μm and 10 μm.

[0049] According to one embodiment, the proportion by weight of the anion exchange compound is between 1% and 30% by weight of the thermal insulation filler, preferably between 5% and 20% by weight of the thermal insulation filler.

[0050] According to one embodiment, the fraction by volume occupied by the anion exchange compound in the thermally insulating filling is less than 5%, preferably less than 1%.

[0051] According to one embodiment, the enclosure comprises a rigid frame comprising a bottom plate, a cover plate and spacer elements which hold the bottom plate and the cover plate parallel and spaced a distance from each other to absorb pressure, the spacer elements of the modular blocks being made in various ways.

[0052] In one embodiment, the spacer elements of the modular block include side walls, internal partitions and / or load-bearing columns, in particular load-bearing columns of small cross-section, wherein the side walls are positioned on the edges of the bottom plate and the cover plate, the internal partitions extend between two opposite edges of the bottom plate and between two opposite edges of the cover plate, and the load-bearing columns are distributed on the inner surfaces of the bottom plate and the cover plate.

[0053] A second subject matter according to the invention consists in a sealed and thermally insulated tank comprising at least one thermally insulating barrier and a sealing membrane which abuts against said thermally insulating barrier and wherein the thermally insulating barrier comprises a plurality of modular blocks as described above.

[0054] According to one embodiment of the second subject of the present invention, the sealing film is made of a nickel-iron alloy having a low thermal expansion coefficient, that is, a linear (in length) thermal expansion coefficient of less than or equal to 2.0×10 -6 K -1 , where K represents Kelvin. Preferably, the sealing film is More specifically, the sealing film is an alloy of iron (64%) and nickel (36%).

[0055] In a specific embodiment, the thermal insulation barrier is a secondary insulation barrier and the sealing film is a secondary sealing film, and the tank additionally includes a primary thermal insulation barrier and a primary sealing film, the primary thermal insulation barrier abuts the secondary sealing film, and the primary sealing film abuts the primary insulation barrier and is used to contact the fluid contained in the tank.

[0056] In another specific embodiment, the thermal insulation barrier is a primary insulation barrier, and the sealing film is a primary sealing film for contacting the fluid contained in the tank, and the tank additionally includes a secondary sealing film and a secondary insulation barrier, the primary thermal insulation barrier abuts against the secondary sealing film, and the secondary sealing film abuts against the secondary insulation barrier.

[0057] In one embodiment, the sealed and thermally insulated tank is used to store a liquid selected from the group consisting of liquefied natural gas, liquefied petroleum gas, liquid methane, liquid ethane, liquid propane, liquid argon, and liquid hydrogen.

[0058] Such a tank may form part of an onshore storage facility, for example, for storing LNG, or be installed in a floating structure in coastal waters or at sea, in particular in an LNG tanker, a floating storage and regasification unit (FSRU), a floating production storage and offloading unit (FPSO), etc. In the case of a floating structure, the tank may be used for transporting liquefied gas or for receiving liquefied gas used as fuel for propelling the floating structure, for example in a tanker of any type.

[0059] According to one embodiment, a liquid cargo ship for transporting liquid products comprises a double hull and the above-mentioned tank arranged in the double hull.

[0060] According to one embodiment, the present invention also provides a method for loading and unloading such a tank, wherein the liquid product is transferred from a floating or onshore storage device to the tank of a liquid cargo ship through an isolated pipeline, or the liquid product is transferred from the tank of a liquid cargo ship to a floating or onshore storage device through an isolated pipeline.

[0061] According to one embodiment, the present invention also provides a transmission system for liquid products, which includes: the above-mentioned tank; an isolated pipeline, which is arranged to connect the tank installed in the hull of a liquid cargo ship to a floating or onshore storage device; and a pump, which is used to drive the liquid product flow from the floating or onshore storage device to the tank of the liquid cargo ship through the isolated pipeline or to drive the liquid product flow from the tank of the liquid cargo ship to the floating or onshore storage device through the isolated pipeline. BRIEF DESCRIPTION OF THE DRAWINGS

[0062] A better understanding of the present invention will be obtained, and other objects, details, features and advantages of the present invention will become more apparent, from the following description of a number of specific embodiments thereof, given by way of illustration only and not by way of limitation, with reference to the accompanying drawings, in which:

[0063] [ Figure 1 ] is a partial cross-sectional view of a sealed tank wall comprising thermally insulated modular blocks presenting a rigid wood encapsulation.

[0064] [ Figure 2 ] is a three-dimensional schematic diagram of a thermally insulated modular block, which may be included in Figure 1 in the tank wall and includes columns.

[0065] [ Figure 3 ] is a perspective view of a modular formwork element having a plurality of anchor studs and a load bearing structure for coupling with thermally insulating modular blocks.

[0066] [ Figure 4 ] is related to Figure 3 A similar perspective view in which the modular formwork elements have been removed and the connecting partitions have been added.

[0067] [ Figure 5 ] is the same as described in Example 4 Cross-sectional view of the complete setup of the sample corresponding to the corrosion reduction test.

[0068] [ Figure 6 ] is a schematic cross-sectional view of an LNG liquid cargo ship tank and a dock for loading / unloading the tank. DETAILED DESCRIPTION

[0069] Reference Figure 1, the area of ​​the double hull of the tanker, indicated by the number 1, can be seen. The tank wall comprises, in order along the thickness of the tank wall: a secondary insulation barrier 2 formed by juxtaposed modular blocks 3 on the double hull 1, which are retained on the double hull 1 by secondary retaining elements 4; then a secondary sealing membrane 5, which is carried by the modular blocks 3; then a primary insulation barrier 6 formed by juxtaposed modular blocks 7, which are retained on the secondary sealing membrane 5 by primary retaining elements 8, which are themselves fixed to the secondary retaining elements 4; and finally a primary sealing membrane 9, which is carried by the modular blocks 7. Further details of the structure of the modular blocks 3 and 7 can be found in publication FR-A-2867 831.

[0070] The internal space of the modular block 3 is filled with a heat-insulating filler not shown, which is packed in a flexible bag or in the form of a compacted block, and the heat-insulating filler includes a mixture of a powdered insulating material and at least one anion exchange compound, wherein the powdered insulating material includes a main component selected from fumed silica, silica aerogel, and a mixture thereof. The anion exchange compound includes an LDH compound and / or an exchangeable anion OH - or CO3 2- A cross-linked anion exchange polymer, such as a cross-linked ion exchange polymer III ( product code 104767).

[0071] Reference Figure 2 According to another embodiment, the modular block 53 comprises a bottom plate 54 on which a distributed support plate 55 is fixed. Column rows 56 and column rows 60 rest on the corresponding distributed support plates 55 and are always fixed to the corresponding distributed support plates 55. In particular, the columns 57 in each column row 56 or column row 60 extend along the thickness of the modular block 53 and therefore extend in a direction perpendicular to the load-bearing wall 1. The columns 57 present a solid rectangular cross-section. Each column row 56 or column row 60 is parallel relative to the lateral ends 58 of the modular block 53. The column rows carry the reinforced covering plates 59. In particular, the columns 57 enable the stress applied to the covering plates 59 to be transferred to the wall 1 and have a compressive strength function. Further details about the structure of the modular block 53 can be found in the publication WO-A-2014020257.

[0072] The space between the columns 57 is filled with a thermal insulation filler not shown, which is packaged in a flexible bag or in the form of a compacted block, and includes a mixture of a powdered insulation material and at least one anion exchange compound, the powdered insulation material including a main component selected from fumed silica, silica aerogel, and a mixture thereof.

[0073] Reference Figure 3 , describes the incorporation of thermally insulating modular blocks into a sealed and thermally insulating tank wall according to one embodiment. Such a sealed wall makes it possible to produce tanks or closed chambers for the storage and / or transportation of cryogenic fluids such as liquefied gases, such as methane. Anchoring studs 11, also referred to as couplers, are uniformly positioned and fixed to an external load-bearing structure 12. In particular, the load-bearing structure 12 can be a self-supporting metal sheet or more generally any type of rigid partition presenting appropriate mechanical properties, such as a concrete wall in an onshore structure. Modular formwork elements 13 are placed against the load-bearing structure 12 between the anchoring studs 11. Therefore, the modular formwork elements 13 present an inwardly protruding shape relative to the plane of the load-bearing structure 12. The modular formwork elements 13 form a plurality of compartments together with the anchoring studs 11 and the load-bearing structure 12. The modular formwork elements 13 are longitudinal beams arranged perpendicularly relative to each other to form compartments presenting a rectangular shape. The modular formwork elements 13 may be provided with releasable fixing elements so that the modular formwork elements 13 can be fixed to the load bearing structure 12 and / or the anchor studs 11. The compartments are subsequently filled with compressed sheets of thermal insulating filler 15 through their open sides to form a plurality of insulating areas of compressed thermal insulating filler 15. The compartments thus define a formwork for the production of said insulating areas 15.

[0074] In one embodiment, the powdered insulating material is mixed with short fibers, such as glass fibers, before forming the compressed panel. In this embodiment, the compressed panel comprises a thermally insulating filler which comprises fibers in addition to the powdered insulating material.

[0075] The compartments are filled with a heat-insulating filler not shown, and the heat-insulating filler includes a mixture of a powdered insulating material including a main component selected from fumed silica, silica aerogel, and a mixture thereof, and at least one anion exchange compound.

[0076] When modular formwork elements 13 are removed, the insulating areas made of compressed thermal insulating filler 15 are separated by the gaps formed by the removal of the formwork elements.

[0077] To ensure continuity of thermal insulation, Figure 4The connecting insulating element 18 shown in fills the gap between the insulating areas made of compressed thermal insulating fillers 15. The connecting insulating element 18 is also arranged between the insulating areas made of compressed thermal insulating fillers 15 under compressive stress. Therefore, when the insulating areas made of compressed thermal insulating fillers 15 shrink under the influence of low temperature, the connecting insulating element 18 can relax and fill the gap between the areas. According to one embodiment, the connecting insulating element 18 is a strip made of a flexible material, such as glass wool, polyester filler, polyurethane (PU) foam, melamine foam, polyethylene (PE) foam, polypropylene (PP) foam or silicone foam. The width of these strips is determined so that: at ambient temperature, the strip is subjected to the compressive stress generated between the insulating areas made of compressed thermal insulating fillers 15.

[0078] The composition and preparation process of the thermal insulation filler used to form the thermally insulating modular blocks will be described below.

[0079] The thermal insulation filler is produced from a powdered insulation material and at least one anion exchange compound, the powdered insulation material including silica aerogel, hydrophobic fumed silica, and mixtures thereof.

[0080] Hydrophobic fumed silica is available, for example, under the commercial reference Aerosil R974 or the commercial reference Aerosil R812S, which compounds are produced by Evonik.

[0081] Silica aerogels are available, for example, under the commercial reference P100 produced by Cabot Corporation and ground into particles with a size of less than 100 μm.

[0082] The thermal insulation filler may also include a granular filler comprising small expanded perlite available under the trade designation CR615 produced by KD One Co., or glass microspheres available under the trade designation Glass Bubble K1 produced by 3M, or a granular silica aerogel known to be compatible with liquid nitrogen under the trade designation P400 produced by Cabot Corporation.

[0083] Example 1: Preparation of anion exchange compounds of the hydrotalcite type

[0084] Anion exchange compounds were purchased from Sigma-Aldrich. The anion exchange compound is a white powder of synthetic hydrotalcite, the product code of which is 652288 and has a molecular weight of 603.98 g / mol. The density of the anion exchange compound is 2.06, and the particle size of the anion exchange compound is between 1 μm and 5 μm.

[0085] Example 2: Preparation of polymer-based anion exchange compounds

[0086] Anion exchange compounds were purchased from Sigma-Aldrich. The ion exchange resin obtained under product number 104767 and named as ion exchanger III (strongly basic anion exchanger, OH-form) was used for analysis. The anion exchange compound is a powder of a cross-linked polymer. The density of the anion exchange compound is 650 kg / m 3 Up to 700kg / m 3 The particle size of the anion exchange compound is between 496 μm and 674 μm.

[0087] The polymer was placed in a 70ZPS impact mill at 16,000 rpm for 80 min. 3 For an air circulation flow rate of 1.25 rpm / h, the selector of the impact mill was adjusted to 8000 rpm.

[0088] The table below gives the results of the particle size distribution of the powders before and after grinding as measured by a Malvern brand Mastersizer 3000.

[0089] [Table 1]

[0090] D10(v) D50(v) D90(v) Before grinding 559 683 835 After grinding 4.25 11.2 19.6

[0091] "DXX(v)=A" means that the proportion by volume of the particle distribution is XX% exhibiting a diameter smaller than A μm.

[0092] A powder exhibiting a particle size between 1 μm and 50 μm is obtained, wherein only 10% of the particles exhibit a diameter greater than 19.6 μm.

[0093] Example 3: Preparation of a corrosion-resistant pyrolytic filling with a chloride anion exchanger

[0094] The hydrophobic fumed silica used is of two types:

[0095] -According to the number of Evonik Resource Efficiency GmbH R974 obtained silica having a particle size of less than 200 μm,

[0096] -According to Wacker Chemie AG H30 obtained silica, which exhibits a particle size of less than 200 μm.

[0097] The hydrophobic fumed silica was mixed with hydrotalcite or with a ground ion exchange resin as shown in Table 2.

[0098] Example 4: Addition of anion exchanger to fumed silica Corrosion reduction test

[0099] The alloy was obtained from Aperam Imphy. The alloy was in the form of a hot rolled strip having a thickness of 0.7 mm.

[0100] A specimen having a length of 65 mm and a width of 31.5 mm was taken from the tape. The specimen had no surface defects. To clean the specimen, it was immersed in 95% ethanol for 15 minutes with the application of ultrasound. The blade was then dried under dry filtered compressed air.

[0101] Various tests shown in Table 2 below were performed.

[0102] [Table 2]

[0103]

[0104] The following accelerated aging protocol was applied. Accelerated aging conditions included a temperature of 55°C and an ambient humidity of 96% RH. Figure 5 The sample holder comprises a bottle 63, a perforated plug 64 including a stopper lip 65, a filter 66, Sample 67 and powder 68.

[0105] The sampling periods for each powder number tested were 100h, 250h, 500h and 1000h.

[0106] Four were tested for each number. Samples (each sample is run for one duration).

[0107] At each sampling, The blade was removed from the sample holder and cleaned of remaining powder traces by a jet of compressed air, then The blades are kept under vacuum to stop corrosion.

[0108] For each campaign, a series of "numbered" samples is added. The samples consist of blade.

[0109] Will The blades were immersed in the mixtures shown in Table 2 above to obtain the quantitative results of surface corrosion rates shown in Tables 3 and 4.

[0110] [Table 3]: Tests on hydrotalcite

[0111]

[0112] * Localized corrosion points

[0113] [Table 4]: Tests on polymer-type ground basic anion exchangers

[0114] Duration No. 2 R974+10R H30+10R R974+20R H30+20R 100h 0.00％ 0.00％ 0.00％ 0.00％ 0.00％ 250h 0.00％ 0.00％ 0.00％ 0.00％ 0.00％ 500h 0.00％ 0.00％ 0.00％ 0.00％ 0.00％ 1000h 0.00％ 0.00％ 0.00％ 0.00％ 0.00％

[0115] In summary, this experiment has demonstrated that the addition of a mixture of ion exchangers precharged with OH- inhibits the effect of fumed silica on Corrosiveness of the specimen.

[0116] The above-described insulating blocks can be used in different types of containers, for example, to form a primary insulating barrier or a secondary insulating barrier of an LNG container in an onshore facility or a floating structure such as an LNG tanker, etc. In a preferred embodiment, the thermal insulating barrier using modular insulating blocks is kept at a low pressure during operation of the container, that is, for example, a partial vacuum is formed in the space between the load-bearing wall and the secondary membrane or between the secondary membrane and the primary membrane to further improve thermal insulation.

[0117] Reference Figure 6 , a terminal for loading / unloading tanks of LNG tankers includes a loading and unloading station 75, a submarine pipeline 76 and a land-based equipment 77. The loading and unloading station 75 is a fixed offshore equipment including a movable arm 74 and a tower 78, which supports the movable arm 74. The movable arm 74 carries a bundle of insulated flexible hoses 79 that can be connected to the loading / unloading pipeline 73. The rotating movable arm 74 is suitable for LNG tankers of all sizes. A connecting pipeline (not shown) extends inside the tower 78. The loading and unloading station 75 allows the LNG tanker 70 to be loaded from the land-based equipment 77 and the LNG tanker 70 to be unloaded to the land-based equipment 77. The equipment includes a liquefied gas storage tank 80 and a connecting pipeline 81, which is connected to the loading or unloading station 75 via an underwater pipeline 76. The underwater pipeline 76 allows the transfer of liquefied gas between the loading or unloading station 75 and the land-based facility 77 over greater distances, such as 5 km, which can keep the LNG tanker 70 at a greater distance from the coast during loading and unloading operations.

[0118] To generate the pressure required for the transfer of the liquefied gas, pumps carried on board the tanker 70 and / or pumps provided by the land-based facility 77 and / or pumps provided by the loading and unloading station 75 may be used.

[0119] Although the present invention has been described in conjunction with a number of specific embodiments, it is very obvious that the present invention is by no means limited thereto and that if technical equivalents of the described devices and combinations thereof fall within the scope of the present invention, the present invention includes all technical equivalents and combinations of these technical equivalents.

[0120] Use of the verb "comprise" or "include" and its conjugations does not exclude the presence of other elements or stages than those stated in a claim.

[0121] In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim.

[0122] Although the present invention has been described in conjunction with a number of specific embodiments, it is very obvious that the present invention is by no means limited thereto and that if technical equivalents of the described devices and combinations thereof fall within the scope of the present invention, the present invention includes all technical equivalents and combinations of these technical equivalents.

[0123] Use of the verb "comprise" or "include" and its conjugations does not exclude the presence of other elements or stages than those stated in a claim.

[0124] In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim.

Claims

1. A thermally insulating modular block (3, 7) for insulating a sealed tank for storing liquid, the modular block (3, 7) comprising a thermally insulating filler, the thermally insulating filler comprising a powdered insulating material and at least one anion exchange compound, the powdered insulating material comprising a main component selected from the following and a mixture of the following: fumed silica, silica aerogel, the anion exchange compound capable of capturing chloride anions in exchange for releasing at least one other anion, the anion exchange compound exhibiting a selected from OH - and CO3 2- and in the form of a powder mixed with said powdered insulating material, The thermally insulating filler is not enclosed in an airtight enclosure.

2. The modular block according to claim 1, characterized in that The anion exchange compound is selected from the group consisting of clay, layered double hydroxides, synthetic hydrotalcite, anions containing exchangeable OH - and CO3 2- of cross-linked polymers.

3. The modular block according to claim 2, characterized in that The layered double hydroxide has a molecular formula [M II 1-x M III x (OH)2] x+ [A m- x / m .nH2O] x- , where M II and M III are the divalent and trivalent cations of the sheet, respectively, and A represents the anionic interlayer entity.

4. Modular block according to one of claims 1 to 3, characterized in that The anion exchange compound is provided in the form of particles having an average apparent size of between 1 μm and 50 μm.

5. Modular block according to one of claims 1 to 3, characterized in that The proportion by weight of the anion exchange compound is between 1% and 30% by weight of the thermal insulation filler.

6. Modular block according to one of claims 1 to 3, characterized in that The anion exchange compound occupies a fraction by volume of less than 5% in the thermal insulation filler.

7. Modular block according to one of claims 1 to 3, characterized in that The modular block includes a gas-permeable envelope defining at least one compartment, the thermally insulating filler being disposed in the compartment.

8. The modular block according to claim 7, wherein: The air-permeable enclosure comprises a rigid frame including a bottom plate, a cover plate and spacer elements which hold the bottom plate and the cover plate parallel and at a distance from each other to absorb pressure.

9. The modular block according to claim 8, characterized in that The spacer element comprises side walls positioned on the edge of the bottom panel and the edge of the cover panel.

10. The modular block according to claim 8, characterized in that The spacer element comprises an inner divider extending between two opposite edges of the bottom panel and between two opposite edges of the cover panel.

11. The modular block according to claim 8, characterized in that The spacer element comprises a load bearing column (57).

12. Modular block according to one of claims 1 to 3, characterized in that The thermally insulating filler includes fibers.

13. A sealed and thermally insulated tank comprising at least one thermally insulating barrier and a metallic sealing membrane, the metallic sealing membrane resting against the thermally insulating barrier, and wherein, The thermal insulation barrier comprises a plurality of modular blocks (3, 7) according to any one of claims 1 to 3.

14. The tank according to claim 13, wherein The sealing film is made of a nickel-steel alloy, and the nickel-steel alloy has a strength of less than or equal to 2.0×10 -6 K -1 The linear thermal expansion coefficient.

15. The tank according to claim 13, wherein: The thermal insulation barrier is a secondary insulation barrier and the sealing film is a secondary sealing film, the tank additionally comprises a primary thermal insulation barrier and a primary sealing film (9), the primary thermal insulation barrier abuts against the secondary sealing film, the primary sealing film (9) rests against the primary thermal insulation barrier, and the primary sealing film (9) is used to contact with the fluid contained in the tank.

16. The tank according to claim 13, wherein: The thermal insulation barrier is a primary thermal insulation barrier, and the sealing film is a primary sealing film (9) for contacting the fluid contained in the tank, the tank additionally comprising a secondary sealing film and a secondary insulation barrier, the primary thermal insulation barrier being placed against the secondary sealing film, and the secondary sealing film being placed against the secondary insulation barrier.

17. The tank according to claim 13, wherein: The tank is used for storing a liquid selected from the group consisting of: liquefied natural gas, liquefied petroleum gas, liquid methane, liquid ethane, liquid propane, liquid argon and liquid hydrogen.

18. A tanker (70) for transporting liquids, the tanker comprising a double hull (72) and a tank (71) according to claim 13 installed in the double hull.

19. A transmission system for liquid, the transmission system comprising a liquid cargo ship (70) according to claim 18, an isolation pipe (73, 79, 76, 81) and a pump, the isolation pipe (73, 79, 76, 81) being arranged to connect the tank (71) installed in the double hull of the liquid cargo ship to a floating or onshore storage device (77), the pump being used to drive the liquid flow from the floating or onshore storage device through the isolation pipe to the tank of the liquid cargo ship, or being used to drive the liquid flow from the tank of the liquid cargo ship through the isolation pipe to the floating or onshore storage device.

20. A method for loading or unloading a tanker (70) according to claim 18, wherein: Liquid is transferred from a floating or onshore storage facility (77) to the tank (71) of the liquid cargo ship through an insulated pipeline (73, 79, 76, 81), or liquid is transferred from the tank (71) of the liquid cargo ship to a floating or onshore storage facility (77) through an insulated pipeline (73, 79, 76, 81).

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