Cryogenic storage system

Abstract

Storage system for storing a cryogenic medium, in particular for storing hydrogen, comprising a storage container (1) for receiving the medium, wherein a first extraction line forms a fluid-conducting connection from the interior of the storage container (1) to a consumer connection (10) for connecting a consumer, wherein at least a first controllable line shut-off valve (6) and a first heat exchanger (3) are arranged in the first extraction line, wherein a second extraction line, different from the first extraction line, forms a fluid-conducting connection from the interior of the storage container (1) to a consumer connection (10) for connecting the same consumer, wherein at least a second controllable line shut-off valve (7) and a further first heat exchanger (3) are arranged in the second extraction line, characterized in thatthat the first withdrawal line additionally has a third controllable line shut-off valve (9) immediately before the consumer connection (10) and the second withdrawal line additionally has another third controllable line shut-off valve (9) immediately before the consumer connection (10).

Description

Field of invention

[0001] The present invention relates to a storage system for storing a cryogenic medium, in particular hydrogen. The invention also relates to a device comprising such a storage system and a consumer for the medium contained in the storage container of the storage system. State of the art

[0002] It is known that cryogenic media, i.e., extremely cold and at least partially liquid media such as hydrogen or helium, can be stored in a storage container to transport energy, for example to power a vehicle, an aircraft, or a rocket. The medium is typically present partly in liquid form and partly in gaseous form within the storage container.

[0003] In known cryogenic storage systems, various pipes connect the inner tank to the external environment. These pipes serve different purposes, such as conveying cryogenic liquid from the inner tank to a heat exchanger or evaporator, and ultimately to a consumer. Sometimes, such storage systems also include a pressure build-up system, which, depending on the type, can be either open or closed. A pressure build-up system compensates for the pressure drop that occurs when gaseous or liquid liquid, for example, hydrogen, is withdrawn. This is typically achieved either through an inner tank heat exchanger (closed piping system) or through direct evaporation (open system).

[0004] In known cryogenic storage systems, there is a supply line that connects the inside of the tank to a consumer. If a component in this supply line fails, the system typically shuts down because the supply of the medium from the inner tank to the consumer is no longer possible.

[0005] From DE 10 2006 025 656 A1, a device for the cryogenic storage and conveyance of fuel for supplying a consumer, in particular an internal combustion engine powering a motor vehicle, is known, wherein the device comprises at least: a cryogenic tank, consisting of at least an inner container for receiving the cryogenic medium, which is held in a thermally insulated outer container, a coolable cooling shield between the inner container and the outer container of the cryogenic tank, a heat sink which, as a heat energy storage device, is in heat-transferring contact with the cooling shield, and a filling and extraction device with at least one line penetrating the outer container and opening into the inner container, at least for filling with or extracting the fuel.for the extraction of cryogenic medium, wherein the heat sink is in heat-transferring contact with the line for the cryogenic medium in order to reduce the heat input from the environment into the inner container by releasing heat, wherein the inner container has a recess in which at least the heat sink and the line for the cryogenic medium are accommodated in such a way that they are substantially within the circumferential contour of the inner container. Summary of the invention

[0006] It is an object of the invention to provide a storage system for storing a cryogenic medium and a device comprising such a storage system and a consumer for the medium contained in the storage container of the storage system, which is fault-tolerant, wherein in particular a failure of a single component of a withdrawal line should not lead to a total failure of the supply of a consumer from the storage system.

[0007] The problem is solved by a storage system for storing a cryogenic medium, in particular for storing hydrogen, with the further features according to claim 1.

[0008] The storage system comprises a storage tank for receiving the medium, wherein a first extraction line forms a fluid-conducting connection from the interior of the storage tank to a consumer connection for connecting a consumer, wherein at least a first controllable line shut-off valve and a first heat exchanger are arranged in the first extraction line, wherein a second extraction line, distinct from the first extraction line, forms a fluid-conducting connection from the interior of the storage tank to a consumer connection for connecting the same consumer, wherein at least a second controllable line shut-off valve and a further first heat exchanger are arranged in the second extraction line.

[0009] According to the invention, the first supply line additionally has a third controllable shut-off valve immediately before the consumer connection, and the second supply line additionally has a further third controllable shut-off valve immediately before the consumer connection. The third controllable shut-off valve can serve as a shut-off device upstream of the connected consumer.

[0010] According to the invention, the extraction line of a storage system comprises a controllable shut-off valve to regulate the withdrawal of the medium from the storage container into the extraction line, and downstream of this shut-off valve, a first heat exchanger. This heat exchanger serves to temper the withdrawn medium, particularly hydrogen, to the desired extraction conditions, in particular to heat it and, if liquid medium is withdrawn, to evaporate it. According to the invention, such an extraction line, from the inner container to a consumer, is redundantly configured twice—or even more often. Therefore, according to the invention, there is a first extraction line and a different second extraction line, each extraction line having identical components so that the extraction lines can perform the same function.In particular, both the first and second extraction lines have an associated line shut-off valve to control the flow into the extraction line, as well as an associated heat exchanger to temper the medium to the desired extraction conditions.

[0011] In conventional cryogenic storage systems, the number and type of piping are limited to a minimum for thermodynamic reasons. In contrast, the invention uses a higher number of components.

[0012] Individual component failures therefore no longer lead to a total system failure (shutdown), since the components and the connection to the consumer are not simply connected to the internal tank, but are redundantly designed.

[0013] The first and second extraction lines can, for example, both be configured to extract gaseous medium from the storage tank, or both be configured to extract liquid medium from the storage tank. Alternatively, the first extraction line can be configured to extract gaseous medium from the storage tank and the second extraction line to extract liquid medium from the storage tank.

[0014] In one embodiment, the consumer connection of the first supply line and the consumer connection of the second supply line are combined into a single common connection. In an alternative embodiment, the two consumer connections are not combined into a single common connection. The two consumer connections can therefore form either one common connection or two separate connections on the same consumer.

[0015] Preferably, the first extraction line additionally includes an internal tank heat exchanger downstream of the first heat exchanger, and the second extraction line additionally includes a further internal tank heat exchanger downstream of the second internal tank heat exchanger. The internal tank heat exchanger in each extraction line serves to control or regulate the pressure inside the storage tank by means of the heated extracted medium.

[0016] Preferably, the first extraction line has an additional second heat exchanger downstream of the internal tank heat exchanger, and the second extraction line has a further second heat exchanger downstream of the additional internal tank heat exchanger. These second heat exchangers ensure that the desired extraction conditions for the medium are maintained even after heat transfer by the internal tank heat exchanger of the respective extraction line.

[0017] Preferably, the first extraction line additionally has a partial flow control valve after the first controllable line shut-off valve and before the inner tank heat exchanger, and the second extraction line additionally has another partial flow control valve after the second controllable line shut-off valve and before the second inner tank heat exchanger. The partial flow control valves allow, optionally, only a portion of the extracted and heated medium to be returned to the storage tank or to the respective inner tank heat exchanger.

[0018] In general, in a storage system according to the invention, all components of the first extraction line up to the consumer connection, such as pipes, heat exchangers and valves, can also be redundantly present in the second extraction line and arranged in the same order.

[0019] Preferably, the storage tank is double-walled, with an insulating vacuum space between the two walls. According to one embodiment, the first and second controllable line shut-off valves and / or the first two heat exchangers of the first and second extraction lines are arranged in the vacuum space; more preferably, the second heat exchangers of the first and second extraction lines are also located there.

[0020] According to another embodiment, the first and second controllable line shut-off valves and / or the first heat exchangers of the first and second extraction lines are arranged outside an outer container of the storage tank, wherein at least parts of lines outside an outer container of the storage tank are designed as vacuum-insulated lines.

[0021] The problem can also be solved by a device comprising a storage system, as previously described, and a consumer for the medium contained in the storage vessel, wherein the consumer connection of the first withdrawal line and the consumer connection of the second withdrawal line are connected to the consumer. The consumer connection of the first withdrawal line and the consumer connection of the second withdrawal line can be combined into a common connection on the consumer, or alternatively, they can be separated into two distinct connections on the consumer. Brief description of the drawings

[0022] The invention is described below by way of example with reference to the drawings. Fig. Figure 1 is a schematic representation of a storage system according to the invention. Fig. Figure 2 is a schematic representation of a storage system according to the invention in an alternative embodiment. Fig. Figure 3 is a schematic representation of a storage system according to the invention in an alternative embodiment. Fig. Figure 4 is a schematic representation of a storage system according to the invention in an alternative embodiment. Fig. Figure 5 is a schematic representation of a storage system according to the invention in an alternative embodiment. Fig. Figure 6 is a schematic representation of a storage system according to the invention in an alternative embodiment. Fig. Figure 7 is a schematic representation of a storage system according to the invention in an alternative embodiment. Fig. Figure 8 is a schematic representation of a storage system according to the invention in an alternative embodiment. Fig. Figure 9 is a schematic representation of a storage system according to the invention in an alternative embodiment. Fig. Figure 10 is a schematic representation of a storage system according to the invention in an alternative embodiment. Detailed description of the invention

[0023] In the Fig. Figure 1 shows a storage system according to the invention for storing a cryogenic medium, in particular for storing hydrogen.

[0024] The storage system comprises a storage container 1 for holding the medium. The storage container 1 forms an inner container of a double-walled container, which additionally comprises an outer container 11. A vacuum is created between the outer container 11 and the inner container, i.e., storage container 1. Furthermore, suspensions 13 are arranged section by section between the outer container 11 and the inner container to position the two halves of the double-walled container relative to each other.

[0025] The cryogenic medium, in particular hydrogen, is located in the lower part of the storage container 1, namely below the liquid surface shown as a wavy line in the Fig. as liquid in the container, and above the wavy liquid surface in a gaseous state.

[0026] A gas extraction line 2 is configured to extract the gaseous medium from the storage container 1, such that the free end of the gas extraction line 2 terminates in the storage container 1 above the liquid surface, near the top of the container. The first extraction line begins with the gas extraction line 2.

[0027] A liquid extraction line 5 is configured to extract the liquid medium from the storage tank 1, such that the free end of the liquid extraction line 5 terminates below the liquid surface, near the bottom of the storage tank 1. The second extraction line begins with the liquid extraction line 5.

[0028] The terms "ceiling" and "floor" refer to the usual installation position of the storage container, for example in a moving or flying transport device, whereby gravity acts towards the bottom of the storage container during normal operation of the transport device.

[0029] A first controllable line shut-off valve 6 is arranged in the gas extraction line 2, and a second controllable line shut-off valve 7 is arranged in the liquid extraction line 5. Both line shut-off valves are located outside the storage tank 1. Fig. 1. The line shut-off valves are also located outside the outer tank 11.

[0030] In the alternative version of the storage system, which is in Fig. As shown in Figure 2, the two line shut-off valves 6, 7 are arranged inside the outer container 11, i.e. between the inner container, storage container 1, and the outer container 11 of the double-walled storage container, namely in the vacuum space.

[0031] The line shut-off valves are controlled by a control device, which is also located in the vacuum chamber ( Fig. 2) or outside the entire container ( Fig. 1) can be arranged, controllable. In this case, the flow through the line shut-off valves can preferably not only be interrupted or released, but also reduced.

[0032] The storage tank 1 can also be refuelled from a refuelling device 14 via the gas extraction line 2 and / or the liquid extraction line 5, preferably also via the first line shut-off valve 6 and / or the second line shut-off valve 7.

[0033] The gas extraction line 2 and the liquid extraction line 5 also run as two separate lines after the two line shut-off valves 6, 7, each with its own assigned components, and therefore form two separate extraction lines.

[0034] The gas extraction line 2 and the liquid extraction line 5 are separate extraction strands with their respective assigned connections outside the storage tank 1, for example between storage tank 1 and outer tank 11 of the double-walled storage tank ( Fig. 2), arranged, first heat exchanger 3 for heating the extracted medium flow-connected.

[0035] Downstream of the first heat exchanger 3, an inner tank heat exchanger 4 is arranged within the storage tank 1 for heating the liquid medium in the storage tank 1. The heated medium, drawn from the storage tank 1, flows through this inner tank heat exchanger. The heating process in the inner tank heat exchanger 4 partially heats and evaporates the liquid medium in the storage tank 1.

[0036] In the gas extraction line 2 and in the liquid extraction line 5 of the design according to Fig. 1 to Fig. 3 is not a controllable three-way valve, i.e., no partial flow valve 15 is arranged, so that all the medium drawn off through the gas extraction line 2 and / or through the liquid extraction line 5 and heated by the first heat exchanger 3 reaches the inner tank heat exchanger 4. In the embodiments according to Fig. 4 to Fig. 4 a partial flow valve 15 is arranged in each extraction line, so that optionally only a part of the medium extracted through the gas extraction line 2 and / or through the liquid extraction line 5 and heated by the first heat exchanger 3 reaches the respective inner tank heat exchanger 4.

[0037] Downstream of the respective inner tank heat exchanger 4 and outside the storage tank 1, outside ( Fig. 1) or within ( Fig. 2) of the outer container 11 of the double-walled container, a second heat exchanger 8 is arranged for heating the medium in the first extraction line and in the second extraction line.

[0038] The medium flowing through the first and / or second extraction line is fed downstream of the respective internal tank heat exchanger 4 to the same consumer via a respective consumer connection 10, in particular a fuel cell. A third line shut-off valve 9 is arranged in each extraction line between the second heat exchanger 8 and the consumer 10.

[0039] The embodiment of the Fig. 2 differs from the Fig. 1, that control-relevant components of both extraction lines of the storage system, such as the first heat exchangers 3, the second heat exchangers 8, the first line shut-off valve 6 and the second line shut-off valve 7, are arranged inside the outer tank 11, not outside the outer tank 11 as in Fig. 1, and are thus arranged in the space between the double-walled container, which forms a vacuum space.

[0040] Two separate areas of the vacuum chamber can be used exclusively for the heat exchangers 3 and 8 of the first extraction line and for the heat exchangers 3 and 8 of the second extraction line. This allows faults in one extraction line to be detected more easily and assigned to the affected extraction line. The separation of the two areas of the vacuum chamber can be achieved by the suspensions 13.

[0041] In the execution of the Fig. 3 The lines running outside the storage container between the components of the respective extraction line are designed as vacuum-insulated lines 16.

[0042] Thus, the cryogenic valves 6 and 7, as well as the heat exchangers 3 and 8, and the shut-off devices 9 can all be positioned outside the tank system ( Fig. 1) For example, in cryogenic storage systems, where this cannot be easily implemented technically due to the very low temperatures and associated ice formation or other safety-relevant conditions, these components can be located within the vacuum range ( Fig. 2) Place only those components outside that are necessary for the isolation. Alternatively, for example to better utilize the installation space because no components need to be placed between inner tank 1 and outer tank 11, the cryogenic lines and components can be connected using vacuum-insulated lines 16 to minimize or eliminate the occurrence of cryogenic temperatures or other safety-related problems ( Fig. 3).

[0043] As already mentioned, the entire extraction flow can be routed through the internal tank heat exchanger 4 (see Fig. 1, Fig. 2 and Fig. 3) However, this may be undesirable in some applications, which may necessitate an additional component, namely a partial flow control valve 15. This serves, for example, to direct a percentage-controlled mass flow through the internal tank heat exchanger 4, thereby establishing a controlled and thus stabilized operating range (see Fig. 4, Fig. 5 and Fig. 6).

[0044] To ensure the continued extraction of the medium for mobile applications even in the event of a single failure, redundancy is introduced into the storage system according to the invention. However, doubling the cryogenic valves, i.e., the first and second controllable line shut-off valves 6 and 7, is not necessary. This measure allows for the implementation of a system that can compensate for the failure of individual components and therefore prevent the loss of functionality of the storage system. There are two extraction lines, which can differ in the type of extraction (gas, liquid). Due to the redundant design with two unconnected extraction lines, if a component in one extraction line fails or leaks, the other can take over the full functionality of the other.Particularly in the aviation and automotive sectors, a scenario where a single failure or fault leads to the shutdown of the entire tank system is undesirable. A further advantage is that, despite the redundant design, significantly more components are not required. One extraction line can be designed and configured for the extraction of liquid cryogenic medium. The second line can provide the capability for extraction of gaseous medium. This allows the storage system, despite the new type of piping, to switch between the extraction methods, which can be desirable for improved tank system performance.

[0045] In order to detect an error in the event of a single fault and to enable a change in the withdrawal method, various methods for monitoring the system can be implemented: One method involves installing the components (all components necessary for extraction, downstream of the cryogenic valves) in an extended vacuum zone (secondary vacuum), for example, at the end face or along the tank axis. This allows leaks to be detected quickly and a change in the extraction method can be implemented before the system fails.

[0046] For example, if this installation space cannot be used, in a second method the extraction lines can be monitored using vacuum-insulated pipes 16 in order to detect failures and leaks if necessary.

[0047] The components for the auxiliary system must therefore be designed differently, or rather, each is installed for a worst-case scenario for both extraction lines. If necessary, this also means that the storage system can have two pressure build-up systems, since each extraction line should have the ability to regulate the tank pressure independently, as this component could also fail. Reference symbol list 1 storage container 2 Gas extraction lines 3 first heat exchanger 4 first internal tank heat exchanger 5 Liquid extraction line 6 first controllable line shut-off valve 7 second controllable line shut-off valve 8 second heat exchanger 9 third controllable line shut-off valve 10 Consumer connection 11 external containers 13 Suspension 14 Refueling device 15 Partial flow control valve 16 Vacuum-insulated cable

Claims

[1] Storage system for storing a cryogenic medium, in particular for storing hydrogen, comprising a storage container (1) for receiving the medium, wherein a first extraction line forms a fluid-conducting connection from the interior of the storage container (1) to a consumer connection (10) for connecting a consumer, wherein at least a first controllable line shut-off valve (6) and a first heat exchanger (3) are arranged in the first extraction line, wherein a second extraction line, distinct from the first extraction line, forms a fluid-conducting connection from the interior of the storage container (1) to a consumer connection (10) for connecting the same consumer, wherein at least a second controllable line shut-off valve (7) and a further first heat exchanger (3) are arranged in the second extraction line. characterized by, that the first withdrawal line additionally has a third controllable line shut-off valve (9) immediately before the consumer connection (10) and the second withdrawal line additionally has another third controllable line shut-off valve (9) immediately before the consumer connection (10). [2] Storage system according to claim 1, characterized by , that the consumer connection (10) of the first withdrawal line and the consumer connection (10) of the second withdrawal line are combined into a common connection. [3] Storage system according to any of the preceding claims, characterized by , that the first extraction line additionally has an internal tank heat exchanger (4) after the first heat exchanger (3) and the second extraction line additionally has another internal tank heat exchanger (4) after the further first heat exchanger (3) [4] Storage system according to claim 3, characterized by, that the first extraction line additionally has a second heat exchanger (8) after the inner tank heat exchanger (4) and the second extraction line additionally has a further second heat exchanger (8) after the further inner tank heat exchanger (4). [5] Storage system according to claim 3 or 4, characterized by , that the first extraction line additionally has a partial flow control valve (15) after the first controllable line shut-off valve (6) and before the inner tank heat exchanger (4) and the second extraction line additionally has a further partial flow control valve (15) after the second controllable line shut-off valve (7) and before the further inner tank heat exchanger (4). [6] Storage system according to any of the preceding claims, characterized by, that all components of the first extraction line up to the consumer connection (10), such as pipes, heat exchangers and valves, are also redundantly present in the second extraction line and arranged in the same order. [7] Storage system according to any of the preceding claims, characterized by , that the storage container (1) is designed as a double-walled structure, with an insulating vacuum space between the two walls of the storage container (1), wherein the first and second controllable line shut-off valves (6, 7) and / or the first heat exchangers (3) of the first and second extraction line are arranged in the vacuum space, preferably also the second heat exchangers (8) of the first and second extraction line. [8] Storage system according to any of the preceding claims, characterized by, that the storage tank (1) is designed as a double-walled structure with an insulating vacuum space between the two walls of the storage tank (1), wherein the first and second controllable line shut-off valves (6, 7) and / or the first heat exchangers (3) of the first and second extraction line are arranged outside an outer container (11) of the storage tank (1), wherein at least parts of lines outside the outer container (11) of the storage tank (1) are designed as vacuum-insulated lines (16). [9] Device comprising a storage system according to one of the preceding claims and a consumer for the medium contained in the storage container, characterized by, that the consumer connection (10) of the first withdrawal line and the consumer connection (10) of the second withdrawal line are connected to the consumer, wherein the consumer connection (10) of the first withdrawal line and the consumer connection (10) of the second withdrawal line are combined into a common connection at the consumer or are not combined into a common connection at the consumer.

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