DE102021001004A1 - Storage tank - Google Patents

Abstract

Storage container (5) for liquid hydrogen (H2), with a first container (8) for receiving the liquid hydrogen (H2), a second container (15) in which the first container (8) is accommodated, one with a vacuum applied to it Gap (19) which is provided between the first container (8) and the second container (15), a first insulation element (20) which is received in the gap (19) and which encloses the first container (8), and a second insulation element (25) which differs from the first insulation element (20) and which is received in the gap (19) and which surrounds the first insulation element (20).

Description

The invention relates to a storage container for liquid hydrogen.

The applicant is familiar with in-house double-walled storage containers for liquid hydrogen which have an inner container, an outer container and thermal insulation arranged between the inner container and the outer container. When such storage containers are used for maritime purposes, there is a risk that the thermal insulation of the storage container will be damaged in the event of a fire. This can have the consequence that the hydrogen evaporates in an undesirable way and also ignites the fire. Since there are limited possibilities of escape when using such a storage container on a ship, protection of the thermal insulation against heat-related impairment is desirable.

Against this background, the object of the present invention is to provide an improved storage container.

Accordingly, a storage container for liquid hydrogen is proposed. The storage container comprises a first container for receiving the liquid hydrogen, a second container in which the first container is received, a gap to which a vacuum is applied, which is provided between the first container and the second container, a first insulation element which is in the Gap is received and which encloses the first container, and a different from the first insulation element second insulation element which is received in the gap and which encloses the first insulation element.

Because the second insulation element is provided between the first insulation element and the second container, the first insulation element is protected from damage in the event of a fire. In particular, the heat input into the first insulation element is reduced. This significantly increases the length of time that the storage container can withstand a fire.

The storage container is particularly suitable for maritime applications. The storage tank can therefore be referred to as a maritime storage tank. For example, the storage container can be mounted on or on a vehicle, in particular on or on a watercraft. Accordingly, a vehicle, in particular a watercraft, with such a storage container is also proposed. The storage container can also be referred to as a storage tank, a hydrogen storage container or a hydrogen storage tank. The storage container is preferably suitable for holding liquid hydrogen. However, the storage container can also be used for other cryogenic liquids. Examples of cryogenic fluids or liquids, or cryogens for short, are, for example, liquid helium, liquid nitrogen or liquid oxygen.

After or during the filling of the hydrogen, a gas zone with gaseous hydrogen and a liquid zone below with liquid hydrogen are formed in the storage container. A phase boundary is provided between the gas zone and the liquid zone. After filling the storage container, the hydrogen thus has two phases with different states of aggregation, namely liquid and gaseous. The hydrogen can pass from the liquid phase to the gaseous phase and vice versa.

The first container can also be referred to as an inner container or an inner tank, and the second container can also be referred to as an outer container or an outer tank. The first container and the second container in particular each have a tubular or cylindrical base section which is closed on both sides by a cover section. The gap envelops or completely encloses the first container in particular. That is, the first gap is thus provided both between the base portions of the first container and the second container and between the lid portions of the first container and the second container. The gap thus runs completely around the first container.

The fact that the first insulation element is “received” in the first gap means in the present case that the first insulation element is arranged in the gap. That is to say, the first insulation element is completely enclosed by the second container.

Furthermore, the first insulation element completely encloses the first container. The first insulation element thus accommodates the first container or envelops it. The first insulation element is used in particular to provide thermal insulation for the first container. The first insulation element can therefore also be referred to as the first thermal insulation element. The terms “insulation element” and “thermal insulation element” can therefore be interchanged.

The second insulation element is also, in particular, completely enclosed by the second container. Furthermore, the second insulation element completely encloses the first insulation element and thus accommodates the first insulation element and the first container. The second The insulation element thus accommodates the first insulation element or envelops it. The second insulation element also serves in particular for thermal insulation. The second insulation element can therefore also be referred to as a second thermal insulation element.

The fact that the second insulation element “differs” from the first insulation element means in the present case that the first insulation element and the second insulation element are two separate components. However, this does not rule out the fact that the second insulation element and the first insulation element are placed on top of one another or in one another. The first insulation element and the second insulation element can differ from one another in that the first insulation element is made of a different material than the second insulation element. The first insulation element and the second insulation element can also differ from one another in terms of their structure. For example, the first insulation element can have a multilayer structure and the second insulation element can be in the form of granules.

The fact that the gap is “acted upon” by a vacuum means in the present case that there is a negative pressure in the gap. In the present case, a “vacuum” is to be understood as meaning, in particular, a pressure of less than 300 mbar, preferably less than 10 ^-3 mbar, more preferably less than 10 ^{-7 mbar.} However, the pressure can also be lower. The vacuum can be a rough vacuum or a fine vacuum. The first insulation element and the second insulation element are preferably not fluid-tight, in particular not gas-tight, so that the first insulation element and the second insulation element can be subjected to the vacuum.

According to one embodiment, the storage container comprises a metal foil which is arranged between the first insulation element and the second insulation element.

The metal foil thus separates the first insulation element from the second insulation element. The metal foil is used in particular to fix the first insulation element to the first container.

According to a further embodiment, the metal foil is an aluminum foil or a copper foil.

Other suitable materials for the metal foil can also be used. In any case, however, the metal foil is free from organic components. A high temperature resistance of the metal foil can hereby be achieved.

According to a further embodiment, the metal foil completely encloses the first insulation element.

That is, the first insulation element with the first container received in it is completely enveloped or enclosed by the metal foil.

According to a further embodiment, the metal foil is permeable to fluid.

As a result, the vacuum prevailing in the gap can be applied to the first insulation element. The metal foil can have openings or a perforation.

According to a further embodiment, the first container and the second container are constructed to be rotationally symmetrical with respect to a common axis of symmetry.

The storage container can be arranged in such a way that the axis of symmetry is oriented perpendicular to a direction of gravity. In this case, the storage container is arranged horizontally or horizontally. However, the storage container can also be arranged such that the axis of symmetry is arranged parallel to the direction of gravity. In this case, the storage container is arranged upright or vertically.

According to a further embodiment, the second container is cylindrical.

In particular, the second container is circular-cylindrical. In the present case, a “cylinder” is to be understood as a geometry that is rotationally symmetrical to the axis of symmetry. According to a further embodiment, the second container has a cylindrical base section and two cover sections closing the base section at the ends, the cover sections being curved outward with respect to the base section.

According to a further embodiment, the second container has a cylindrical base section and two cover sections closing the base section at the ends, the cover sections being curved outward with respect to the base section.

The base section is constructed to be rotationally symmetrical to the axis of symmetry. The base section has a cylindrical or tubular geometry. A first cover section and a second cover section are provided at the end of the base section. The cover sections are curved in opposite directions.

According to a further embodiment, the first insulation element is multilayered and has alternately arranged layers of aluminum foil and glass paper.

The glass paper can be perforated and / or perforated. In this way, the first insulation element arranged in the gap can be subjected to the vacuum. In the present case, an “aluminum foil” can be understood to mean both a foil made entirely of aluminum and a plastic foil coated with aluminum. Instead of an aluminum foil, however, a gold foil or gold-coated plastic foil can also be used. The first insulation element is in particular a so-called multilayer insulation (MLI). The aforementioned metal foil differs from the aluminum foil at least in terms of its wall thickness. The wall thickness of the metal foil is greater than the wall thickness of the aluminum foil.

According to a further embodiment, the first insulation element and the second insulation element completely fill the gap.

That is, the second insulation element contacts both the first insulation element and the second container. Alternatively, the second insulation element can only partially fill the gap. In this case, an intermediate space can be provided between the second insulation element and the second container. In particular, a gap is provided between the first insulation element and the second container, which gap is filled by the second insulation element. This aforementioned gap can, for example, have a gap width of 100 mm.

According to a further embodiment, the first container and the second container are made of stainless steel.

In this way, sufficient strength of the container can be achieved even at low temperatures.

According to a further embodiment, the first container is supported on the second insulation element.

That is, the first insulation element is in contact with the second insulation element. The second insulation element can - but does not have to - absorb a weight force of the filled first container, the first insulation element and the metal foil at least partially. However, the proportion of the weight force absorbed is preferably so small that the first insulation element is not or at least only slightly compressed. As a result, the insulating properties or insulating properties of the first insulating element are not adversely affected. In particular, because the first container is supported on it, the second insulation element can dampen movements or vibrations of the, in particular filled, first container.

According to a further embodiment, the second insulation element is introduced into the gap as bulk material.

This enables the second insulation element to be easily introduced into the gap. The second insulation element preferably comprises a multiplicity of granules which in their entirety form the second insulation element.

According to a further embodiment, the second insulation element has pearlite.

In particular, the second insulation element is formed from a large number of pearlite grains or pearlite granules. Alternatively, the second insulation element can also comprise glass wool, rock wool or another suitable thermal insulation material.

According to a further embodiment, the storage container further comprises a monitoring device for monitoring the vacuum in the gap.

The monitoring device can have a pressure sensor or be designed as such. The monitoring device can, for example, also be designed as a manometer.

In the present case, “a” is not necessarily to be understood as restricting to exactly one element. Rather, several elements, such as two, three or more, can also be provided. Every other counting word used here is also not to be understood to the effect that an exact restriction to exactly the corresponding number of elements must be implemented. Rather, numerical deviations upwards and downwards are possible.

Further possible implementations of the storage container also include combinations, not explicitly mentioned, of features or embodiments described above or below with regard to the exemplary embodiments. The person skilled in the art will also add individual aspects as improvements or additions to the respective basic shape of the storage container.

• 1 zeigt eine schematische Seitenansicht einer Ausführungsform eines Fahrzeugs;
• 2 zeigt eine schematische Schnittansicht einer Ausführungsform eines Speicherbehälters für das Fahrzeug gemäß 1; und
• 3 zeigt die Detailansicht III gemäß der 2.

Further advantageous configurations of the storage container are the subject matter of the subclaims and of the exemplary embodiments of the storage container described below. in the Furthermore, the storage container is explained in more detail on the basis of preferred embodiments with reference to the accompanying figures.

• 1 shows a schematic side view of an embodiment of a vehicle;
• 2 FIG. 11 shows a schematic sectional view of an embodiment of a storage container for the vehicle according to FIG 1 ; and
• 3 shows the detailed view III according to FIG 2 .

In the figures, elements that are the same or have the same function have been given the same reference symbols, unless otherwise stated.

the 1 shows a greatly simplified side view of an embodiment of a vehicle 1 . The vehicle 1 can for example be a maritime watercraft, in particular a ship. The vehicle 1 can be described as a maritime vehicle. In particular, the vehicle 1 be a maritime passenger ferry. Alternatively, the vehicle can 1 also be a land vehicle or an aircraft. In the following, however, it is assumed that the vehicle 1 is a watercraft.

The vehicle 1 includes a fuselage 2 that is buoyant. On or on the fuselage 2 is a bridge 3 intended. The vehicle 1 is preferably operated with hydrogen. The vehicle can do this 1 a fuel cell 4th exhibit. In the present case, a “fuel cell” is to be understood as a galvanic cell which converts the chemical reaction chemistry of a continuously supplied fuel, in this case hydrogen, and an oxidizing agent, in this case oxygen, into electrical energy. With the aid of the electrical energy obtained, for example, an electric motor (not shown) can be driven, which in turn is a propeller for driving the vehicle 1 drives.

To supply the fuel cell 4th with hydrogen is a storage tank 5 intended for storing liquid hydrogen. The storage container 5 is rotationally symmetrical to a central or symmetry axis 6th built up. The storage container 5 can for example be inside the fuselage 2 , especially within an engine room, on the bridge 3 or on one as a foundation 7th acting deck of the hull 2 be arranged. Here is the axis of symmetry 6th perpendicular to a direction of gravity G oriented. That is, the storage container 5 is positioned horizontally or horizontally. Thus is the axis of symmetry 6th parallel to the foundation 7th placed. Alternatively, the storage container 5 however, it can also be positioned upright or vertically. In this case is the axis of symmetry 6th along the direction of gravity G oriented. Furthermore, the axis of symmetry is 6th in this case also perpendicular to the foundation 7th placed.

the 2 shows a schematic sectional view of an embodiment of a storage container as mentioned above 5 . the 3 shows the detailed view III according to FIG 2 . In the following, the 2 and 3 referenced at the same time.

The storage container 5 can also be referred to as a storage tank. As previously mentioned, the storage container is 5 for the absorption of liquid hydrogen H2 (Boiling point: 1 bara: 20.268 K = -252.882 ° C). Therefore, the storage container 5 can also be referred to as a hydrogen storage tank or as a hydrogen storage tank. The storage container 5 however, it can also be used for other cryogenic liquids. Examples of cryogenic fluids or liquids, or cryogens for short, are, in addition to the aforementioned hydrogen H2 liquid helium He (boiling point 1 bara: 4.222 K = -268.928 ° C), liquid nitrogen N2 (boiling point 1 bara: 77.35 K = -195.80 ° C) or liquid oxygen O2 (boiling point: 1 bara: 90.18 K = -182.97 ° C).

The storage container 5 is rotationally symmetrical to the axis of symmetry 6th built up. The storage container 5 comprises an inner container or first container 8th , which is also rotationally symmetrical to the axis of symmetry 6th is constructed. The first container 8th comprises a tubular or cylindrical base section 9 , which is also rotationally symmetrical to the axis of symmetry 6th is constructed. The base section 9 can have a circular or approximately circular geometry in cross section. The base section 9 is on the front on both sides with the help of a cover section 10 , 11 locked. The lid sections 10 , 11 are arched. A first cover section 10 and a second lid portion 11 are curved in opposite directions, so that the cover sections 10 , 11 with respect to the base section 9 are curved outwards. The first container 8th is fluid-tight, in particular gas-tight. The first container 8th is made of stainless steel.

In the first container 8th is the liquid hydrogen H2 recorded. In the first container 8th can as long as the hydrogen H2 located in the two-phase area, a gas zone 12th with vaporized hydrogen, H2 and a liquid zone 13th with liquid hydrogen H2 be provided. The hydrogen H2 so points after filling into the first container 8th two phases with different states of aggregation, namely liquid and gaseous. That is, in the first container 8th there is a phase boundary 14th between the liquid hydrogen H2 and the gaseous hydrogen H2 .

The first container 8th is completely within a second container 15th arranged. The second container 15th can also be referred to as an outer container. The second container too 15th is rotationally symmetrical to the axis of symmetry 6th built up. The second container 15th includes, like the first container 8th , a tubular or cylindrical base section 16 , which is rotationally symmetrical to the axis of symmetry 6th is constructed. The base section 16 can have a circular or approximately circular geometry in cross section. The base section 16 is on the front side of a cover section 17th , 18th locked. In particular, there is a first cover section 17th and a second lid portion 18th intended. The lid sections 17th , 18th are curved in opposite directions, so that the cover sections 17th , 18th with respect to the base section 16 are curved outwards. The second container 15th is fluid-tight, in particular gas-tight. The second container too 15th is made of stainless steel.

Between the first container 8th and the second container 15th is a first vessel 8th completely enveloping or enveloping gap 19th intended. The gap 19th is applied with a vacuum. In the present case, a “vacuum” is to be understood as meaning, in particular, a pressure of less than 300 mbar, preferably less than 10 ^-3 mbar, more preferably less than 10 ^{-7 mbar.} That the gap 19th the first container 8th completely “enveloped” or “enveloped” means here that the gap 19th on the one hand, completely around the circumference of the base section 9 and on the other hand between the two cover sections 10 , 17th as well as between the two cover sections 11 , 18th is provided.

In the gap 19th is a first vessel 8th completely enveloping or enclosing first insulation element 20th ( 3 ) intended. That is, the first insulation element 20th encloses both the base section 9 as well as the lid sections 10 , 11 of the first container 8th . The first isolation element 20th is used for thermal insulation. Therefore, the first insulation element 20th can also be referred to as the first thermal insulation element. The first isolation element 20th is multilayer. That is, the first insulation element 20th comprises a multitude of plies or layers. The first isolation element 20th can therefore also be referred to as a multi-layer insulation element or a multi-layer thermal insulation element.

In particular, is the first insulation element 20th a so-called multilayer insulation (MLI). The first isolation element 20th comprises several alternately arranged layers or plies of perforated and / or embossed aluminum foil 21 as a reflector and glass paper 22nd as a spacer between adjacent aluminum foils 21 . The glass paper 22nd can be perforated and / or perforated. In the 3 are only two layers of aluminum foil each 21 and two layers of glass paper 22nd provided with a reference number. The glass paper 22nd acts as a spacer between two neighboring aluminum foils 21 , whereby the first isolation element 20th with the one in the gap 19th can apply the prevailing vacuum. The first isolation element 20th fills the gap 19th only partially. The first isolation element 20th lies on the outside of the first container 8th at.

The first insulation element is a metal foil 23 assigned to which the first insulation element 20th or the first container 8th completely enveloped or enveloped. The metal foil 23 can for example be an aluminum foil or a copper foil. Compared with the aluminum foil 21 exhibits the metal foil 23 a greater thickness or wall thickness. The metal foil 23 is optional. The metal foil 23 can be part of the first insulation element 20th be. The metal foil 23 is preferably not fluid-tight and therefore fluid-permeable, so that the first insulation element 20th can be evacuated. Between the first insulation element 20th or between the metal foil 23 and the second container 15th is the first insulation element 20th completely enveloping or enveloping gap 24 intended. The gap 24 is in particular part of the gap 19th . The gap 24 can for example have a gap width of 100 mm.

In the gap 19th or in the gap 24 is a different from the first insulation element 20th distinguishing second insulation element 25th arranged. The second isolation element 25th envelops or encloses the first insulation element 20th with the optional metal foil 23 and the first container 8th . The second isolation element 25th encloses the first insulation element 20th Completely. The second isolation element 25th fills together with the first insulation element 20th the gap 19th preferably completely off. However, this is not absolutely necessary. The second isolation element 25th is used for thermal insulation. Therefore, the second insulation element 25th can also be referred to as a second thermal insulation element.

For example, the second insulation element 25th than in the gap 19th Introduced bulk material formed and comprises a large number of granules 26th , of those in the 3 only three are provided with a reference number. For example, the second insulation element 25th a bed of perlite or the like. In this case, the granules are grains 26th Pearlite grains. As an alternative to perlite, however, rock wool, glass wool or any other suitable insulating material can also be used for the second insulation element 25th can be used.

The first container 8th with the first insulation element 20th rests on the second insulation element 25th away. That is, the first insulation element 20th is with the second insulation element 25th in contact. The second isolation element 25th can - but does not have to - a weight force G of the filled first container 8th , the first insulation element 20th as well as the metal foil 23 at least partially record. The proportion of the weight absorbed G is preferably so small that the first insulation element 20th is not or at least only slightly compressed. This increases the insulating properties or insulating properties of the first insulating element 20th not negatively affected. In particular, the second insulation element 25th Movements or vibrations of the filled first container 8th and the first insulation element 20th dampen.

The storage container 5 also has a monitoring device 27 ( 2 ), which is suitable, the vacuum in the gap 19th to monitor. The monitoring device 27 can be a pressure sensor or a manometer or have a pressure sensor or a manometer.

When using the storage container 5 in combination with a maritime vehicle 1 In the event of a fire, due to the limited range of motion, it is necessary that the first container 8th enveloping first insulation element 20th is protected from damage. If the first insulation element is damaged 20th Otherwise it could lead to evaporation and leakage of the hydrogen and thus to an acceleration of the fire. This problem arises with the previously explained storage container 5 solved.

With the help of the second insulation element 25th it is possible to use the first insulation element 20th to protect against the effects of heat. The heat input into the first insulation element due to fire 20th is significantly reduced. The length of time that the storage container 5 Resists fire, can thereby be extended significantly. The use of perlite for the second insulation element 25th enables, on the one hand, good thermal insulation and, on the other hand, the second insulation element 25th at least part of the weight G record and / or movements of the first container 8th dampen.

Although the present invention has been described on the basis of exemplary embodiments, it can be modified in many ways.

List of reference symbols

1

vehicle

2

hull

3

bridge

4th

Fuel cell

5

Storage tank

6th

Axis of symmetry

7th

foundation

8th

container

9

Base section

10

Cover section

11

Cover section

12th

Gas zone

13th

Liquid zone

14th

Phase boundary

15th

container

16

Base section

17th

Cover section

18th

Cover section

19th

gap

20th

Isolation element

21

Aluminum foil

22nd

Glass paper

23

Metal foil

24

gap

25th

Isolation element

26th

Granules

27

Monitoring device

G

Direction of gravity

G

Weight force

H2

hydrogen

Claims (10)

Storage container (5) for liquid hydrogen (H2), with a first container (8) for receiving the liquid hydrogen (H2), a second container (15) in which the first container (8) is accommodated, one with a vacuum applied to it Gap (19) which is provided between the first container (8) and the second container (15), a first insulation element (20) which is received in the gap (19) and which encloses the first container (8), and one that differs from the first insulation element (20) second insulation element (25) which is received in the gap (19) and which encloses the first insulation element (20). Storage tank after Claim 1 , further comprising a metal foil (23) which is arranged between the first insulation element (20) and the second insulation element (25). Storage tank after Claim 2 wherein the metal foil (23) is an aluminum foil or a copper foil. Storage tank after Claim 2 or 3 , wherein the metal foil (23) completely encloses the first insulation element (20). Storage container according to one of the Claims 2 - 4th , wherein the metal foil (23) is fluid-permeable. Storage container according to one of the Claims 1 - 5 , wherein the first container (8) and the second container (15) are constructed rotationally symmetrical to a common axis of symmetry (6). Storage container according to one of the Claims 1 - 6th wherein the second container (15) is cylindrical. Storage tank after Claim 7 wherein the second container (15) has a cylindrical base section (16) and two cover sections (17, 18) closing the base section (16) at the ends, and wherein the cover sections (17, 18) are curved outward with respect to the base section (16) . Storage container according to one of the Claims 1 - 8th wherein the first insulation element (20) is multilayered and has alternating layers of aluminum foil (21) and glass paper (22). Storage container according to one of the Claims 1 - 9 , wherein the first insulation element (20) and the second insulation element (25) completely fill the gap (19).

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