EP4332423A1 - Brenngasspeichersystem - Google Patents

Abstract

The application relates to a fuel gas storage system (200, 300), comprising at least one fuel gas connection (222, 322), set up to provide a fuel gas from a fuel gas distribution network (202, 302), and at least one fuel gas compression arrangement (204, 304), set up to compress the fuel gas provided , at least one fuel gas storage (206, 306), set up for storing the compressed fuel gas, at least one fuel gas expansion arrangement (208, 308), set up for expanding the fuel gas taken from the fuel gas storage (206, 306), the fuel gas connection (222, 322) being set up is for feeding the expanded fuel gas into the fuel gas distribution network (202, 302), the fuel gas expansion arrangement (208, 308) comprising at least one expansion work machine (230, 330, 430).

Description

The application relates to a fuel gas storage system, comprising at least one fuel gas connection, set up to provide a fuel gas from a fuel gas distribution network, at least one fuel gas compression arrangement, set up to compress the fuel gas provided, at least one fuel gas storage (e.g. a cavity artificially created in salt rock), set up to store the compressed Fuel gas, at least one fuel gas expansion arrangement, set up to expand the fuel gas removed from the fuel gas storage, the fuel gas connection being set up to feed the expanded fuel gas into the (public) fuel gas distribution network. In addition, the application relates to a method for operating a fuel gas storage system.

To generate electrical energy and/or heat, it is known from the prior art to burn a fuel gas in a power plant. Examples of fuel gases include natural gas, biogas and hydrogen. A fuel gas is transported via a pipeline network or fuel gas distribution network and is regularly stored using fuel gas storage systems.

Known fuel gas storage systems include at least one fuel gas storage in which the fuel gas is temporarily stored. For this purpose, the fuel gas provided via the fuel gas distribution network is first compressed by a compression arrangement. The compressed fuel gas is then stored in the fuel gas storage. When there is a need for fuel gas, the fuel gas is removed from the storage via an expansion arrangement. The expanded fuel gas is then fed back into the fuel gas distribution network. Furthermore, at least one further process engineering system can be used to prepare the stored fuel gas in accordance with the specifications Return line to the fuel gas distribution network can be provided, such as fuel gas drying or the like.

The Figure 1 shows an exemplary fuel gas storage system 100 of the prior art. The fuel gas storage system 100 includes a fuel gas compression arrangement 104, a fuel gas storage 106 and a fuel gas expansion arrangement 108. Furthermore, an internal fuel gas distribution network 126 is provided in the form of a plurality of pipes.

The fuel gas storage system 100 is coupled to a public fuel gas distribution network 102 via a fuel gas connection 122. The fuel gas connection 122 is set up to provide fuel gas from the fuel gas distribution network 102. This fuel gas is in particular provided or supplied to the fuel gas compression arrangement 104. It should be noted that the direction of flow of the fuel gas in the internal fuel gas distribution network 126 is indicated by arrows.

A fuel gas compression arrangement 104 generally has a plurality of compression stages 114.1, 114.2, 114.x, where x is a natural number. A compression stage 114.1, 114.2, 114.x of the prior art has in particular a compressor 110 and an air cooler 112 downstream of the respective compressor 110.

The fuel gas provided by the fuel gas connection 122 normally has a temperature between approximately 8 ° C and 15 ° C before the first compression stage 114.1. The compressor 110 of the first compression stage 114.1 increases the temperature of the fuel gas to approximately 50 ° C to 150 ° C. In particular, the work done on the fuel gas by the compressor 110 increases the internal energy of the fuel gas and thus its temperature.

In order to avoid damage to the technical components of the compression stages 114.1, 114.2, particularly with a large number of compression stages 114.1, 114.2, 114.x, To avoid 114.x, it is known that an air cooler 112 is connected downstream of each compressor 110. For example, in the first compression stage 114.1, the fuel gas heated to a temperature of up to approximately 150 ° C can be cooled back down to approximately 45 ° C by a downstream air cooler 112.

After the fuel gas has been compressed by the last compression stage 114.x and then cooled down, it is fed into the fuel gas storage 106 through a storage connection 124 of the fuel gas storage 106 and stored there, in particular temporarily stored.

In particular, if there is or is a need for fuel gas in the external fuel gas distribution network 102, the stored fuel gas is removed from the fuel gas storage 106 via the storage connection 124 and, in particular, is made available to a fuel gas expansion arrangement 108. In the case of natural gas, in the prior art the natural gas removed is first heated via a heating device 116 of the fuel gas expansion arrangement 108. Then the preheated natural gas is expanded via a control valve 118 or expansion valve 118. The relaxed natural gas is fed to a gas processing unit 120 and fed into the fuel gas distribution network 102 via the fuel gas connection.

If the fuel gas is hydrogen, then due to the negative Joule-Thomson coefficient of hydrogen compared to natural gas, instead of heating the hydrogen removed, the hydrogen removed is pre-cooled by a cooling device 116 of the fuel gas expansion arrangement 108. The pre-cooled hydrogen is then relaxed via the control valve 118 or expansion valve 118. The relaxed hydrogen is fed to a gas processing unit 120 and fed into the fuel gas distribution network 102 via the fuel gas connection.

A significant amount of external energy is required to operate such a fuel gas storage system. It is therefore necessary to supply the compressors and the air coolers of the fuel gas compression arrangement with electrical energy from an external energy source. It is also necessary to supply the electrical components of the relaxation arrangement described with electrical energy from an external energy source. In other words, the energy expenditure when storing and/or retrieving fuel gas in the known fuel gas storage systems is high.

The application is therefore based on the task of providing a fuel gas storage system in which the need for energy from external energy sources is at least reduced.

This object is achieved according to a first aspect of the application by a fuel gas storage system according to claim 1. The fuel gas storage system comprises at least one fuel gas connection. The fuel gas connection is set up to provide a fuel gas from a fuel gas distribution network. The fuel gas storage system includes at least one fuel gas compression arrangement. The fuel gas compression arrangement is set up to compress the fuel gas provided. The fuel gas storage system includes at least one fuel gas storage. The fuel gas storage is set up to store the compressed fuel gas. The fuel gas storage system includes at least one fuel gas expansion arrangement. The fuel gas expansion arrangement is set up to expand the fuel gas taken from the fuel gas storage. The fuel gas connection is set up to feed the expanded fuel gas into the fuel gas distribution network. The fuel gas expansion arrangement comprises at least one expansion work machine, in particular set up to expand the removed fuel gas, particularly preferably for making use of the internal energy of the fuel gas.

By providing, in contrast to the prior art, a fuel gas storage system with a fuel gas expansion arrangement according to the application, the fuel gas expansion arrangement comprising at least one expansion work machine, in particular set up to expand the removed fuel gas, the need for energy from external energy sources is at least reduced. The expansion work machine can thus replace a heating device or a cooling device as well as the control valve, preferably in the form of a turbine device, so that the external energy requirement is reduced. In addition, the use of a turbine device in particular offers the possibility of recovering energy through the expansion process or during the expansion process. In particular, the internal energy of the fuel gas can be converted into usable energy by the relaxation work machine.

The fuel gas storage system is used to store a fuel gas, in particular for temporarily storing the fuel gas.

A fuel gas is to be understood in particular as meaning a combustible useful gas which is burned or oxidized in an electrochemical converter (e.g. a combustion device, a fuel cell, etc.) of a fuel gas consumer in order to provide, for example, thermal energy and/or electrical energy. According to a preferred embodiment of the fuel gas storage system according to the application, the fuel gas can be selected from the group comprising: natural gas, biogas and hydrogen. In other words, the fuel gas storage system is particularly set up for storing and retrieving natural gas or hydrogen.

A fuel gas is transported in particular via an (external and in particular public) fuel gas distribution network from a fuel gas source to a fuel gas consumer (e.g. gas power plant, gas heating of a building, etc.). A fuel gas distribution network or fuel gas transport network usually comprises a plurality of Transport network pipes or transport network lines through which the fuel gas is transported.

A fuel gas storage system is connected to such an external fuel gas distribution network via at least one fuel gas connection. If, for example, more fuel gas is fed into the external fuel gas distribution network by the at least one fuel gas source than is (currently) required by the at least one fuel gas consumer, then in particular fuel gas can be taken from the external fuel gas distribution network and stored in a fuel gas storage of the fuel gas storage system.

If the fuel gas is natural gas, for example, the fuel gas storage system in particular can be operated essentially seasonally. This means in particular that fuel gas is stored during the warm months and fuel gas is stored out during the cold months.

With the particularly preferred fuel gas hydrogen, multicyclic operation of the fuel gas storage system can be provided. The operation of the fuel gas storage system can in particular follow the availability of electrical energy from so-called renewable energy sources (e.g. sun, wind, etc.). For hydrogen, the fuel source can in particular be an electrically operated electrolysis system. The electrolysis system can in particular be operated with electrical energy to produce hydrogen when electrical energy is available from renewable energy sources, for example from wind power parks and/or photovoltaic parks due to the corresponding meteorological conditions (e.g. high wind speed and/or high solar radiation). Electrical energy is generated than is required by electrical consumers of an external (public) power distribution network. The hydrogen produced can be at least partially taken from the external fuel gas distribution network in the form of a hydrogen distribution network and (intermediately) stored in the fuel gas storage system.

If electrical energy from renewable energy sources is not or hardly available, i.e. if, for example, wind power parks and/or photovoltaic parks generate less electrical energy than is required by electrical consumers of the electricity distribution network due to the corresponding meteorological conditions (e.g. low wind speed and/or low solar radiation). is, stored hydrogen can be removed from the fuel gas storage system, fed into the hydrogen distribution network and made available to a hydrogen power plant in order to generate electrical energy, in particular by burning the hydrogen provided.

The fuel gas connection (e.g. comprising a controllable valve arrangement) is fluidly coupled or connected to a fuel gas compression arrangement. In particular, the fuel gas storage system can include an internal refrigerant distribution network (e.g. formed by a plurality of transport pipes). It is understood that further modules, for example for fuel gas cleaning and/or processing, can be arranged between the fuel gas connection and the fuel gas compression arrangement.

The fuel gas compression arrangement is set up to compress the fuel gas provided. The fuel gas compression arrangement can comprise at least one compressor. A compressor is set up to supply mechanical work to the (enclosed) fuel gas, so that in particular the pressure and density of the fuel gas increases.

Preferably, a fuel gas compression arrangement can comprise a plurality of compression stages, each with a compressor, in order to bring about a specific (predeterminable) compression of the fuel gas provided.

The fuel gas compression arrangement is fluidly coupled or connected to the fuel storage. In particular, the fuel gas storage can have one Include memory port. The fuel gas compression arrangement is connected in particular to the storage connection.

The storage connection (e.g. comprising a controllable valve arrangement) can be set up to feed the compressed fuel gas to be stored into the fuel gas storage and/or to remove the stored fuel gas from the fuel gas storage.

In addition, the fuel gas storage system comprises at least one fuel gas expansion arrangement, which is fluidly connected in particular to the storage connection. According to the application, the fuel gas expansion arrangement has at least one expansion work machine which is set up to expand the fuel gas taken from the fuel gas storage. Relaxation means in particular that the pressure and density of the fuel gas are reduced.

The relaxation work machine can preferably be a turbine device. In other variants of the application, the relaxation work machine can also be a rotary piston device or the like.

A turbine device according to the application may comprise a turbine housing. The turbine housing can be made of metal, especially steel. The turbine housing can have an inlet to which a pipe or line of the internal refrigerant distribution network can be connected. The pipe can lead to the storage connection.

The turbine housing can, in particular on the side of the turbine housing opposite the inlet, have an outlet to which a further pipe or a second line of the internal refrigerant distribution network can be connected. The pipes can in particular be flangeable at the inlet or the outlet.

The turbine device in particular comprises at least one running device arranged (or mounted) on a turbine shaft. The turbine shaft is arranged in particular within the turbine housing. The turbine shaft can therefore be coupled to the running device (mechanically, in particular torque-locked). The running device includes in particular an impeller with a plurality of impeller blades.

The fuel gas flowing from the inlet to the outlet of the turbine device causes in particular a mechanical movement of the running device. This leads to a relaxation of the fuel gas or the fuel gas pressure. In addition, the mechanical movement of the running device is transmitted to the turbine shaft, in particular in a rotational movement of the turbine shaft. The rotational movement can be used further, as will be described.

The relaxed fuel gas is fed (again) into the external fuel gas distribution network via the fuel gas connection, if necessary after further fuel gas processing.

According to a further embodiment of the fuel gas storage system according to the application, the at least one fuel gas storage can be a cavern, in particular a salt cavern. The particular advantage of a salt cavern is that an additional lining is not necessary due to the petrophysical properties of salt.

According to a further preferred embodiment of the fuel gas storage system according to the application, the expansion work machine can be a turbine device and comprise at least one generator. The generator can be set up to generate electrical energy.

Preferably, the turbine shaft is (mechanically) coupled to the at least one generator. The generator is therefore particularly on the turbine shaft arranged or stored. In other variants, an indirect coupling can be provided, for example a gearbox can be interposed.

The generator can in particular convert the rotational movement of the shaft or the rotational energy into electrical energy. In other words, the at least one generator, which is preferably coupled to the turbine shaft, is in particular designed to convert the mechanical energy occurring during the expansion process into electrical energy.

The generator can be an asynchronous machine, for example. The at least one generator can in particular be arranged "floating" in the turbine housing. The generator or the generator housing can be at least partially flowed around by the fuel gas.

The at least one generator can be arranged in front of the running device in the direction of flow. Alternatively, the at least one generator can be arranged behind the running device as seen in the direction of flow or, in addition to the generator as seen in the direction of flow, a further generator can be arranged behind the running device in front of the running device. The arrangement of the at least one generator can depend in particular on the fuel gas to be expanded.

Particularly with hydrogen, it is advantageous to arrange the generator in front of the running device in the direction of flow. With hydrogen, an appropriate arrangement can achieve optimized cooling of the generator.

With natural gas or biogas, it can be advantageous to arrange the generator behind the running device in the direction of flow. The reason for this is that the gas temperature drops due to the gas expansion and therefore the gas in the direction of flow behind the running device has a lower temperature than in front of the running device. Cooling can be improved. The advantage of two generators can in particular, that these can have a smaller interference contour with the same overall performance.

According to a further embodiment of the fuel gas storage system according to the application, the fuel gas storage system can comprise an internal power network. The internal power network can be formed from at least one electrically conductive line, in particular a plurality of lines. It goes without saying that further components such as fuses, switches, etc. can be provided.

The internal power network can in particular be set up to supply at least one electrical consumer of the fuel gas storage system at least partially with the electrical energy generated by the generator. As a result, the electrical energy from an external power source (in particular an external power distribution network), which is required to operate the fuel gas storage system, can be reduced even further. In particular, the at least one electrical consumer can be the at least one compressor of the fuel gas compression arrangement. Preferably, each electrical consumer of the fuel gas storage system can be connected to the internal power network.

In variants of the application, it can be provided that the electrical energy generated by the at least one generator of the turbine device can be fed into the (external) power distribution network (via an electrical network connection) if more electrical energy is generated by the generator than in the fuel gas storage system is needed, and/or if there is high energy demand in the (external) electricity distribution network (or during peak load times).

In particular, it has been recognized that with hydrogen, hydrogen is often swapped out during peak load times, i.e. when (currently) less electrical energy is fed into the external power distribution network than is taken from it. On the one hand, the hydrogen removed can be used Generation of electrical energy is burned by a hydrogen power plant. In addition, in particular to further stabilize the power distribution network, the electrical energy generated by the at least one generator of the turbine device can be fed into the power distribution network.

In addition, according to a further embodiment of the fuel gas storage system according to the application, the fuel gas storage system can comprise at least one rechargeable battery connected to the internal power network. In particular, if the electrical energy requirement of the fuel gas storage system during the expansion of the fuel gas or during storage is lower than the electrical energy generated by the at least one generator, excess electrical energy can be (at least partially) stored in the battery. During the storage or compression of the fuel gas, the at least one electrical consumer of the fuel gas compression arrangement can then preferably be supplied (at least partially) with the electrical energy stored in the battery.

According to a particularly preferred embodiment of the fuel gas storage system according to the application, the expansion work machine, in particular the turbine device, can comprise at least a first heat exchanger. The at least one first heat exchanger can be set up to cool a fluid refrigerant. In variants of the registration, for example, two first heat exchangers can also be provided in the relaxation work machine. A first heat exchanger is in particular designed to (partially) transfer the thermal energy of the fuel gas to the fluid refrigerant.

Preferably, the fluid refrigerant may be selected from the group comprising R124a, COz and NH ₃ . It goes without saying that a different refrigerant can also be used in other variants of the application. In particular, partially halogenated hydrocarbons can be used as refrigerants.

Preferably, the at least one first heat exchanger can be integrated in the turbine housing, in particular can be arranged behind the running device when viewed in the flow direction.

In a preferred embodiment, the generator can be arranged or mounted in particular on the turbine shaft in the flow direction in front of the running device and the first heat exchanger can in particular be arranged or mounted on the turbine shaft in the flow direction behind the running device. In variants of the application, the at least one first heat exchanger can also be arranged in the area of the outlet of the turbine housing or behind the outlet of the turbine housing.

In particular, it has been recognized that the fuel gas cools down as a result of the expansion using the turbine device. The cooled fuel gas can in particular be used for cooling and condensing the fluid refrigerant.

According to a further preferred embodiment of the fuel gas storage system according to the application, the fuel gas compression arrangement can comprise at least a second heat exchanger. The second heat exchanger can be set up to cool the fuel gas. In particular, the second heat exchanger is set up to cool the fuel gas flowing into and/or through the fuel gas compression arrangement.

The fuel gas storage system can preferably include at least one internal refrigerant distribution network. The refrigerant distribution network can comprise at least one pipe or line, in particular a plurality of pipes or lines. The internal refrigerant distribution network can be set up to supply the at least one second heat exchanger at least partially with the fluid refrigerant cooled by the first heat exchanger. In particular can at least the second heat exchanger can be connected to the first heat exchanger (directly or indirectly) via the internal refrigerant distribution network.

In particular, the refrigerant cooled by the first heat exchanger can be transported through the internal refrigerant distribution network via, for example, a forward channel to the second heat exchanger, such that fuel gas and/or compressed fuel gas provided is cooled. The refrigerant heated by the second heat exchanger can be transported through the internal refrigerant distribution network via, for example, a return channel to the first heat exchanger, such that the heated refrigerant is (re)cooled by the cooled fuel gas. In other words, the fuel gas storage system can preferably comprise a refrigeration circuit, which can be formed at least by a first heat exchanger, a second heat exchanger and the internal refrigerant distribution network.

The need for energy from external energy sources can be reduced even further. Air coolers can be dispensed with in the fuel gas compression arrangement or at least the number of air coolers and/or the performance of the air coolers can be reduced.

According to a further preferred embodiment of the fuel gas storage system according to the application, the at least one second heat exchanger can be arranged in the fuel gas compression arrangement, such that the fuel gas provided (seen in the direction of flow) is cooled in front of the at least one compressor (or the first compression stage) of the fuel gas compression arrangement. In other words, viewed in the direction of flow, the at least one second heat exchanger can be positioned between the fuel gas connection and the first compression stage of the fuel gas compression arrangement.

In particular, it has been recognized according to the application that, in contrast to the prior art, in which due to the low performance of an air cooler before the first Compression stage no air cooler is provided, a second heat exchanger can advantageously be installed before the first compression stage in order to cool the fuel gas provided before the first compression.

In particular, tests have shown that the fuel gas provided by the second heat exchanger is heated to a temperature of at least less than 0° C., in particular less than -10° C., preferably less than -15° C., particularly preferably at least (less than) -20 °C can be cooled down. It can thus be achieved that the fuel gas (in particular regardless of the outside temperature) can be fed into the first compressor at a temperature between in particular -10° C and -20° C instead of a temperature between 8 ° C and 15 ° C. This temperature difference can extend through all compression stages. This makes it possible in particular to design the at least one compressor or the at least one compression system, in particular all compressors, with lower performance compared to a fuel gas compression arrangement of the prior art.

According to a further embodiment of the fuel gas storage system according to the application, at least one further second heat exchanger can be arranged after the at least one first compressor and in particular before a further compressor of the fuel gas compression arrangement. For example, at least one further second heat exchanger can be arranged after each compressor. In particular, every second heat exchanger can be connected to the internal refrigerant distribution network. In variants of the application, only one or two second heat exchangers and in particular additionally at least one air cooler can be provided.

In addition, according to a further preferred embodiment of the fuel gas storage system according to the application, the fuel gas storage system can comprise at least a first refrigerant storage. The at least one first refrigerant storage can be set up for storage (in particular Intermediate storage) of the fluid refrigerant cooled by the first heat exchanger. The at least one first refrigerant storage can be connected to the internal refrigerant distribution network, in particular to the forward channel.

By providing at least a first refrigerant storage, it can be achieved that in the event that no cooling of the fuel gas is required by the at least one second heat exchanger during expansion, the cooled down refrigerant can be temporarily stored in the first refrigerant storage. If cooling of the fuel gas is then required by the at least one second heat exchanger (and in particular no expansion is carried out), the second heat exchanger can be supplied with cooled down refrigerant from the first refrigerant storage.

According to a further embodiment of the fuel gas storage system according to the application, the fuel gas storage system can comprise at least a second refrigerant storage. The second refrigerant storage can be set up to store the fluid refrigerant heated by the at least one second heat exchanger. The at least one second refrigerant storage can be connected to the internal refrigerant distribution network, in particular to the return channel.

By providing at least one second refrigerant storage, it can be achieved that in the event that cooling of the fluid refrigerant by the at least one first heat exchanger is not possible during compression (since, for example, no expansion is taking place at the moment), the heated refrigerant is temporarily stored in the second refrigerant storage can be. This can, for example, prevent the heated refrigerant from heating the refrigerant that has been cooled down and stored in the first refrigerant storage.

If cooling is then possible through the at least one first heat exchanger (and in particular expansion of the fuel gas is carried out), the first heat exchanger can be supplied with the heated refrigerant from the second refrigerant storage.

In particular, the refrigeration circuit can include the first refrigerant storage and/or the second refrigerant storage.

Preferably, the fuel gas storage system can comprise at least one refrigerant compressor. The refrigerant compressor can be set up to compress the fluid refrigerant heated by the at least one second heat exchanger. In particular, the refrigerant compressor can be installed in the return channel, in particular behind the optional second refrigerant reservoir when viewed in the flow direction.

In particular, for an optimized flow of fuel gas to the running device (in particular the impeller blades), a guide device or steering device can be arranged in the flow direction in front of the running device of the turbine device. The guide device is coordinated in particular with the running device. Preferably, the guide device is set up to direct the fuel gas to the running device in a specific direction.

Furthermore, the fuel gas storage system can preferably comprise a control device set up to control the fuel gas storage system. In particular, the control device can be set up to control the storage process, i.e. in particular by appropriately controlling the fuel gas connection (e.g. the valve arrangement), the fuel gas compression arrangement (e.g. the at least one compressor) and/or the storage connection (e.g. the valve arrangement). In addition, the control device can be set up to control the removal process, i.e. in particular by appropriately controlling the fuel gas connection (eg the valve arrangement). Fuel gas expansion arrangement and/or the storage connection (e.g. the valve arrangement).

Particularly preferably, the control device can control the previously described refrigeration circuit (as was previously described), in particular by controlling the first and/or second heat exchanger (e.g. the corresponding valves), the first and/or second refrigerant storage (e.g. the corresponding valves) and/or of the refrigerant compressor. Controlling the refrigeration circuit can depend on temperature data, for example from the first and/or second refrigerant storage, which can be provided, for example, by temperature sensors of the control device.

In addition, the control device can be set up to control the distribution of the electrical energy generated by the generator. The control can depend on the network status (in particular on the network frequency) of the external power distribution network to which the fuel gas storage system is connected and/or on the internal power requirement of the fuel gas storage system, as described above.

In particular, the control device can comprise a communication module, set up to receive an instruction message for storing and/or retrieving fuel gas. The control device can then control the fuel gas storage system accordingly.

• Bereitstellen, durch mindestens einen Brenngasanschluss, eines Brenngases aus einem Brenngasverteilnetz,
• Verdichten, durch mindestens eine Brenngasverdichtungsanordnung, des bereitgestellten Brenngases,
• Speichern, durch mindestens einen Brenngasspeicher, des verdichteten Brenngases,
• Entspannen, durch mindestens eine Turbinenvorrichtung mindestens einer Brenngasentspannungsanordnung, des aus dem Brenngasspeicher entnommenen Brenngases, und
• Einspeisen, durch den Brenngasanschluss, des entspannten Brenngases in das Brenngasverteilnetz.

Another aspect of the application is a method for operating a fuel gas storage system, in particular a previously described fuel gas storage system. The procedure includes:

• Providing, through at least one fuel gas connection, a fuel gas from a fuel gas distribution network,
• Compressing, by at least one fuel gas compression arrangement, the fuel gas provided,
• Storing, through at least one fuel gas storage, the compressed fuel gas,
• Relaxing, by at least one turbine device at least one fuel gas expansion arrangement, the fuel gas taken from the fuel gas storage, and
• Feeding the relaxed fuel gas into the fuel gas distribution network through the fuel gas connection.

It should be noted that a module, a device (e.g. the control device), etc. in the present case is at least partially formed by software elements (in particular in the form of computer code that can be executed by a processor) and/or at least partially by hardware elements (processor, memory means, actuator, etc.). can be formed. Furthermore, it should be noted that expressions such as "first", "second", etc. do not indicate an order, but only serve to distinguish two elements.

The features of the fuel gas storage systems and processes can be freely combined with one another. In particular, features of the description and/or the dependent claims can be independently inventive, even if features of the independent claims are completely or partially circumvented, on their own or freely combined with one another.

Fig. 1

eine schematische Ansicht eines beispielhaften Brenngasspeichersystems des Stands der Technik,

Fig. 2

eine schematische Ansicht eines Ausführungsbeispiels eines Brenngasspeichersystems gemäß der vorliegenden Anmeldung,

Fig. 3

eine schematische Ansicht eines weiteren Ausführungsbeispiels eines Brenngasspeichersystems gemäß der vorliegenden Anmeldung,

Fig. 4

eine schematische Ansicht eines Ausführungsbeispiels einer Turbinenvorrichtung gemäß der vorliegenden Anmeldung für ein Brenngasspeichersystem gemäß der vorliegenden Anmeldung, und

Fig. 5

ein Diagramm eines Ausführungsbeispiels eines Verfahrens gemäß der vorliegenden Anmeldung.

There are now a variety of options for designing and further developing the fuel gas storage system according to the application and the method according to the application. On the one hand, reference is made to the patent claims subordinate to the independent patent claims, and on the other hand to the description of exemplary embodiments in conjunction with the drawing. In the drawing shows:

Fig. 1

a schematic view of an exemplary fuel gas storage system from the prior art,

Fig. 2

a schematic view of an exemplary embodiment of a fuel gas storage system according to the present application,

Fig. 3

a schematic view of a further embodiment of a fuel gas storage system according to the present application,

Fig. 4

a schematic view of an embodiment of a turbine device according to the present application for a fuel gas storage system according to the present application, and

Fig. 5

a diagram of an embodiment of a method according to the present application.

Similar reference numerals are used below for similar elements.

The Figure 2 shows a schematic view of an embodiment of a fuel gas storage system 200 according to the present application. The fuel gas storage system 200 is used to temporarily store a fuel gas, preferably natural gas or hydrogen.

The fuel gas storage system 200 includes at least one fuel gas connection 222 (e.g. with a controllable valve arrangement (not shown), set up to provide a fuel gas from an (external) fuel gas distribution network 202. In other words, fuel gas can be supplied from the (external) fuel gas distribution network 202 through the fuel gas connection 222 are removed and fed into the internal fuel gas distribution network 226 of the fuel gas storage system 200. The direction of flow of the fuel gas is indicated in particular by the arrows in the figures.

Furthermore, the fuel gas storage system 200 includes at least one fuel gas compression arrangement 204, in particular with at least one Compressor 210 or a compression system, set up to compress the fuel gas provided.

The fuel gas storage system 200 includes at least one fuel gas storage 206. Preferably, the fuel gas storage 206 can be a salt cavern 206. The compressed fuel gas can be fed into the fuel gas storage 206 via a storage connection 224 (e.g. with a controllable valve arrangement) of the fuel gas storage 206. In other words, the fuel gas storage 206 is set up to store the compressed fuel gas.

How further from the Figure 2 can be seen, the fuel gas storage system 200 comprises at least one fuel gas expansion arrangement 208, set up to expand the fuel gas removed from the fuel gas storage 206. In particular, the fuel gas can be removed from the fuel gas storage 206 via the storage connection 224.

In contrast to the state of the art (cf. Figure 1 ) the fuel gas storage system 200 according to the application comprises at least one expansion work machine 230. In the preferred embodiment shown, the expansion work machine 230 is a turbine device 230, set up to expand the fuel gas taken from the fuel gas storage 206 and in particular still compressed. In other variants of the application, the relaxation work machine can be a rotary piston device, reciprocating piston device or the like.

The fuel gas flowing from the inlet to the outlet of the turbine device 230 causes in particular a mechanical movement of a running device of the turbine device 230. This leads to a relaxation of the fuel gas or the fuel gas pressure.

The fuel gas connection 222 is also set up to feed the expanded fuel gas into the fuel gas distribution network 202.

The Figure 3 shows a schematic view of a further preferred embodiment of a fuel gas storage system 300 according to the present application. To avoid repetition, essentially only the differences from the previous exemplary embodiment are described below Figure 2 described and otherwise reference is made to the comments on this exemplary embodiment.

In the illustrated preferred embodiment, the turbine device 330 includes a generator 334 and a first heat exchanger 336. It is understood that in variants of the application only a generator (with a corresponding internal power network) and no heat exchanger or only a first heat exchanger (with a corresponding refrigerant distribution network ) and no generator can be provided.

The generator 334 is set up to generate electrical energy. The generated electrical energy can be fed into an internal power grid 340 (formed by a plurality of electrically conductive lines) and/or into an external (public) power distribution grid 350. The distribution of the electrical energy to the internal power network 340 and/or the external power distribution network 350 can be carried out in particular by a control device 348 of the fuel gas storage system 300. This can depend in particular on the internal power requirement and/or on the network status of the external power distribution network 350.

In particular, at least one electrical consumer 310, 348 (compressor 310 and control device 348 are shown as electrical consumers as examples) of the fuel gas storage system 300 can be supplied with the electrical energy generated by the generator 334. This can be optional Fuel gas storage system 300 include at least one rechargeable battery (not shown).

How further the Figure 3 As can be seen, the fuel gas storage system 300 in the present case comprises a refrigeration circuit 352. The refrigeration circuit 352 includes the at least one first heat exchanger 336. The first heat exchanger 336 is in particular set up for cooling or cooling a fluid refrigerant (in particular partially fluorinated hydrocarbons) of the refrigeration circuit 352.

The cooled refrigerant can be routed via the internal refrigerant distribution network 342 of the refrigeration circuit 352 to at least one second heat exchanger 338.1, 338.2. In particular, the fuel gas compression arrangement 304 includes the at least one second heat exchanger 338.1, 338.2. A second heat exchanger 338.1, 338.2 is in particular designed to cool the fuel gas that flows through the fuel gas compression arrangement 304.

Like in the Figure 3 is shown, the at least one second heat exchanger 338.1 can be arranged in front of the first compressor 310 or the first compression stage 310, in particular in the flow direction. This second heat exchanger 338.1 is in particular designed to cool the fuel gas provided by the fuel gas connection 322 to at least less than -10 ° C, preferably to less than -15 ° C, particularly preferably to at least -20 ° C.

By way of example, the refrigeration circuit 352 can comprise at least one further second heat exchanger 338.2, for example arranged between two compressors 310. In further variants of the application, at least one further second heat exchanger can be provided and/or at least one air cooler (which can in particular be connected to the internal power network). It is understood that the fuel gas compression arrangement 304 may include three or more compressors or compression stages in other variants of the application.

Optionally, the refrigeration circuit 352 can include at least a first refrigerant storage 344. In particular, if no cooling of the fuel gas is currently required by the second heat exchanger 338.1, 338.2 (for example because no fuel gas is currently being compressed), the cooled refrigerant can be temporarily stored in the first refrigerant storage 344. If cooling of the fuel gas by a second heat exchanger 338.1, 338.2 is then required (for example because a fuel gas is currently being compressed), the refrigerant can be provided to the second heat exchanger 338.1, 338.2 in particular by the first refrigerant storage 344 (particularly if there is currently no expansion of the fuel gas he follows).

In addition, the refrigeration circuit 352 may include at least a second refrigerant storage 346. In particular, if the fluid refrigerant cannot currently be cooled by a first heat exchanger 336 (for example because no fuel gas is currently being expanded), the heated refrigerant can be temporarily stored in the second refrigerant storage 346. If the fluid refrigerant can then be cooled by a first heat exchanger 336 (for example because a fuel gas is currently being expanded), the refrigerant can be provided to the first heat exchanger 336 in particular by the second refrigerant storage 346 (in particular if the fuel gas is not currently being expanded).

In variants of the application, the refrigeration circuit 352 may include further components, such as at least one refrigerant compressor (not shown), for example between the second refrigerant storage and the first heat exchanger.

The control of the refrigeration circuit 352, in particular the components 336, 344, 338.1, 338.2, 346 (or the various valves, not shown) of the refrigeration circuit 352, can be carried out by the control device 348. Sensors not shown in the refrigeration circuit (e.g. temperature sensors for detecting the Temperature in the refrigerant stores 344, 346, level sensors for detecting the level in the refrigerant stores 344, 346 etc.), which can provide the control device 348 with the respectively recorded sensor data. The control of the refrigeration circuit 352 may depend on this sensor data.

In addition, the control device 348 can be set up to control the storage process and / or the removal process, for example depending on a received control signal or instruction message, for example containing an instruction to store a certain amount of fuel gas, for example within a certain period of time or to remove a certain amount of fuel gas, for example within a certain period of time.

It is understood that in variants of the application, a plurality of sequentially switched expansion machines, in particular turbine devices, can be implemented in the fuel gas expansion arrangement, in particular in order to obtain a specific pressure level.

The Figure 4 shows a schematic view of a preferred embodiment of a turbine device 430 according to the present application for a fuel gas storage system according to the present application, for example as described in FIG Figure 2 or Figure 3 is shown.

The turbine device 430 is used in particular to carry out a fuel gas pressure relief from a first fuel gas pressure level (before the turbine device 430) to a second, lower fuel gas pressure level (after the turbine device 430), preferably at the same time mechanical energy being converted into electrical energy by a generator 434 of the turbine device 430 and in particular a fluid refrigerant is cooled by a first heat exchanger 436.

The turbine device 430 shown includes a turbine housing 456 (e.g. made of steel or another metal). The turbine housing 456 is in particular essentially tubular. In variants of registration, a different form may also be provided.

The turbine housing 456 has an input 468 and an output 470. In the present exemplary embodiment, the arrow 472 shows the direction of flow of the fuel gas through the turbine device 430. As can be seen, the fuel gas flows through the turbine housing 456 from the inlet 468 to the outlet 470 essentially without a change in direction.

The turbine device 430 shown comprises at least one running device 464 arranged on a turbine shaft 466. The running device 464 can in particular comprise an impeller with a plurality of impeller blades.

Furthermore, the turbine device 430 in the present exemplary embodiment comprises at least one guide device 462 arranged in front of the running device 464 in the flow direction 472. The guide device 462 can in particular have a plurality of nozzle channels, which in particular can and preferably impart a swirl to the fuel gas in accordance with the blading of the impeller 464 accelerate.

The turbine device 430 shown includes at least one generator 434 coupled to the turbine shaft 466 and set up to convert the mechanical energy into electrical energy. In particular, the kinetic energy of the fuel gas flowing through the turbine device 430 is converted into electrical energy by the running device 464, turbine shaft 466 and generator 434. The electrical energy generated can, for example, be fed into the described internal power network or external power distribution network.

Like from the Figure 4 As can be seen, in the present exemplary embodiment the generator 434 is arranged in front of the guide device 462. As already described, the generator 434 can be held “floating” in the turbine housing 456 by a carrier 458. The guide device 462 is integrated into the carrier 458 in this exemplary embodiment.

In addition, in the present case the first heat exchanger 436 is arranged behind the guide device 462 in the flow direction 472. In particular, the thermal energy of the fuel gas flowing through the turbine device 430 is used by the first heat exchanger 436. The fluid refrigerant can be cooled in a simple manner. The first heat exchanger 436 can be held or stored in the turbine housing 456 via a further carrier 458.

The Figure 5 shows a diagram of an exemplary embodiment of a method according to the present application. The method is used in particular to operate a fuel gas storage system, such as that in Figure 2 or 3 is described. The method can in particular be carried out under control by a control device of the fuel gas storage system.

In a first step 501, a fuel gas from a fuel gas distribution network is provided through at least one fuel gas connection, as described above.

In the next step 502, the provided fuel gas is compressed by at least one fuel gas compression arrangement, as described above.

In step 503, the compressed fuel gas is stored by at least one fuel gas storage, as described above. Steps 501 to 503 are in particular steps of storage process 507.

In step 504, fuel gas can be removed from the fuel gas storage.

Then, in step 505, the fuel gas removed from the fuel gas storage is expanded by at least one expansion machine, in particular a turbine device, at least one fuel gas expansion arrangement, as described above.

In step 506, the expanded fuel gas is fed into the fuel gas distribution network through the fuel gas connection, as described above. Steps 504 to 506 are in particular steps of the storage process 508.

Reference symbol list

100

Prior art fuel gas storage system

102

Fuel gas distribution network

104

fuel gas compression arrangement,

106

Fuel gas storage

108

Fuel gas expansion arrangement

110

compressor

112

Air cooler

114

compression stage

116

Cooling device, heating device

118

Control valve or relief valve

120

Gas processing

122

Fuel gas connection

124

Memory port

126

Fuel gas distribution network

200

Fuel gas storage system

202

Fuel gas distribution network

204

Fuel gas compression arrangement

206

Fuel gas storage

208

Fuel gas expansion arrangement

210

compressor

222

Fuel gas connection

224

Memory port

226

Fuel gas distribution network

230

Relaxation work machine, especially turbine device

300

Fuel gas storage system

304

Fuel gas compression arrangement

310

compressor

322

Fuel gas connection

330

Relaxation work machine, especially turbine device

334

generator

336

first heat exchanger

338

second heat exchanger

340

power grid

342

Refrigerant distribution network

344

first refrigerant storage

346

second refrigerant storage

348

Control device

350

Electricity distribution network

352

Refrigeration cycle

430

Relaxation work machine, especially turbine device

434

generator

436

first heat exchanger

456

Turbine housing

458

carrier

462

Guidance device

464

Running facility

466

turbine shaft

468

Entrance

470

Exit

472

Direction of flow

Claims (10)

Fuel gas storage system (200, 300), comprising: - at least one fuel gas connection (222, 322), set up to provide a fuel gas from a fuel gas distribution network (202, 302), - at least one fuel gas compression arrangement (204, 304), set up to compress the fuel gas provided, - at least one fuel gas storage (206, 306), set up to store the compressed fuel gas, - at least one fuel gas expansion arrangement (208, 308), set up to expand the fuel gas taken from the fuel gas storage (206, 306), - wherein the fuel gas connection (222, 322) is set up to feed the expanded fuel gas into the fuel gas distribution network (202, 302),
characterized in that - The fuel gas expansion arrangement (208, 308) comprises at least one expansion work machine (230, 330, 430). Fuel gas storage system (200, 300) according to claim 1, characterized in that - the fuel gas is selected from the group comprising: natural gas, biogas and hydrogen. Fuel gas storage system (200, 300) according to claim 1 or 2, characterized in that - The relaxation work machine (230, 330, 430) is a turbine device (230, 330, 430) and comprises at least one generator (334, 434), set up to generate electrical energy. Fuel gas storage system (200, 300) according to claim 3, characterized in that - the fuel gas storage system (200, 300) comprises an internal power network (340), set up to supply at least one electrical consumer (310, 348) of the fuel gas storage system (200, 300) at least partially with the electrical energy generated by the generator (334, 434). . Fuel gas storage system (200, 300) according to one of the preceding claims,
characterized in that - The expansion work machine (230, 330, 430) comprises at least one first heat exchanger (336, 436), set up for cooling a fluid refrigerant. Fuel gas storage system (200, 300) according to claim 5, characterized in that - the fuel gas compression arrangement (204, 304) comprises at least one second heat exchanger (338.1, 338.2), set up to cool the fuel gas, and - the fuel gas storage system (200, 300) comprises at least one internal refrigerant distribution network (342), set up to supply the at least one second heat exchanger (338.1, 338.2) at least partially with the fluid refrigerant cooled by the first heat exchanger (336). Fuel gas storage system (200, 300) according to claim 6, characterized in that - The at least one second heat exchanger (338.1, 338.2) is arranged in the fuel gas compression arrangement (204, 304) in such a way that the fuel gas provided is cooled in front of the at least one compressor (310) of the fuel gas compression arrangement (204, 304). Fuel gas storage system (200, 300) according to one of claims 5 to 7, characterized in that - The fuel gas storage system (200, 300) comprises at least one first refrigerant storage (344), set up to store the fluid refrigerant cooled by the first heat exchanger (336). Fuel gas storage system (200, 300) according to one of claims 5 to 8, characterized in that - The fuel gas storage system (200, 300) comprises at least one second refrigerant storage (346), set up to store the fluid refrigerant heated by the at least one second heat exchanger (338.1, 338.2). Method for operating a fuel gas storage system (200, 300), in particular a fuel gas storage system (200, 300) according to one of the preceding claims, comprising: - Providing, through at least one fuel gas connection (222, 322), a fuel gas from a fuel gas distribution network (202, 302), - Compressing, by at least one fuel gas compression arrangement (204, 304), the fuel gas provided, - storing, through at least one fuel gas storage (206, 306), the compressed fuel gas, - Relaxing, by at least one expansion machine (230, 330, 430) at least one fuel gas expansion arrangement (208, 308), the fuel gas taken from the fuel gas storage (206, 306), and - Feeding the relaxed fuel gas into the fuel gas distribution network (202, 302) through the fuel gas connection (222, 322).

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