Fuel tank arrangement and method in a liquid hydrogen fuel supply system

Abstract

The invention relates to a fuel tank arrangement in a liquid hydrogen fuel supply system (1) for storing and providing hydrogen for a gas consumer (8), the system comprising: - an inlet line (11) for providing fuel to a tank (10), - the inlet line (11) having a first valve (111) at a first end and a second valve (112) at a tank end, - the inlet line (11) being provided with an inert gas flushing medium line (13) having a first end connected to the inlet line (11) downstream of the first valve (111) and a second end controllably connected to an inert gas source (130) for inert gas flushing of the inlet line (11), - the inlet line (11) being provided with a fuel gas flushing medium line (14) having a first end controllably connected to the inlet line (11) downstream of the first valve (111) and a second end connected to a gaseous hydrogen source (15) for feeding gaseous hydrogen to the inlet line (11) for performing a first flushing of the inlet line (11). The invention also relates to a method using the arrangement.

Description

Technical Field

[0001] This invention relates to the arrangement structure of fuel storage tanks in a liquid hydrogen fuel supply system. The invention also relates to a method for filling a liquid hydrogen fuel supply system.

[0002] More specifically, the present invention relates to a fuel tank arrangement structure in a liquid hydrogen fuel supply system for storing and supplying hydrogen to a gas consumer, the system comprising:

[0003] - Inlet pipeline used to supply fuel to the storage tank;

[0004] -The inlet pipeline has a first valve at the first end and a second valve at the tank end;

[0005] - The inlet pipeline is provided with an inert gas flushing medium pipeline, the first end of which is connected to the inlet pipeline downstream of the first valve, and the second end of which is controllably connected to an inert gas source for performing inert gas flushing on the inlet pipeline.

[0006] More specifically, the method of the present invention relates to a method for filling a liquid hydrogen fuel supply system for storing and supplying liquid hydrogen to a gas consumer, the method comprising the following steps:

[0007] - A predetermined amount of liquid hydrogen is supplied from the fuel loading station to the storage tank via an inlet pipeline having a first valve at a first end and a second valve at the storage tank end, and the first valve is closed after the supply;

[0008] - The inlet line is inertized by supplying inert gas via an inert gas flushing medium line that is controllably connected downstream of the first valve, the supplied inert gas flushing hydrogen from the inlet line into the storage tank. Background Technology

[0009] Because its combustion results are less harmful than those of heavy or light fuel oils, natural gas has become increasingly common as a fuel for internal combustion engines in marine vessels, power plants, and other applications due to environmental concerns. However, gaseous fossil fuels are generally also harmful to the environment, so any leakage into the atmosphere is undesirable. This is why all equipment used for handling and regulating gaseous fuels is subject to stringent safety regulations. In the transition from fossil fuels to renewable fuels, the next step may be hydrogen. If the gaseous fuel is hydrogen, the same or even stricter regulations apply because it has a lower boiling point than liquefied natural gas (LNG). Hydrogen molecules are also smaller, making them more prone to leakage.

[0010] Hydrogen is one of the most promising alternative fuels for the future. It can be used in internal combustion piston engines as a fuel mixture. For example, with LNG, it can be used in a manner that includes up to a certain percentage of the total fuel mixture. Alternatively, hydrogen can be used as the sole fuel for fuel cells. A fuel cell is an electrochemical cell that converts the chemical energy of a fuel such as hydrogen and an oxidant into electricity through a pair of redox reactions. Fuel cell systems differ from most batteries in that they require a continuous source of fuel and oxygen to sustain the chemical reactions. In this sense, the requirements of hydrogen-based power systems are closer to those of LNG fuel systems than those of battery-based systems.

[0011] However, for various reasons, both the storage tanks and the spaces connecting them require special attention. First, the storage and processing of hydrogen typically carries a high risk of fire and explosion, partly due to the wide range of mixtures that can create explosive atmospheres, and partly due to the low typical ignition energy of hydrogen. Second, hydrogen detection is relatively slow.

[0012] For reference, WO 2020 / 182308 A1 discloses a fuel tank arrangement structure for a marine vessel, comprising: a liquid hydrogen fuel tank; a tank connection space arranged in communication with the liquid hydrogen fuel tank, the tank connection space being provided with a ventilation mast having a lower end, an upper end, and an interior, the interior of the ventilation mast forming a ventilation outlet pipeline for discharging gas from the tank connection space; and an emergency pressure relief valve connected to the gas space of the fuel tank via a safety valve pipeline, wherein a first hydrogen outlet pipeline disposed in the ventilation mast is separate from the ventilation outlet pipeline, the first hydrogen outlet pipeline extending from the lower end of the ventilation mast to its upper end, and being arranged in flow communication with the emergency pressure relief valve.

[0013] In EP 2212186 B1, a method for operating an LNG-fueled marine vessel is proposed. The vessel includes: a refueling station comprising an inlet pipe to which an LNG source is arranged; and an LNG storage tank connected to the refueling station and an LNG-fueled power plant. In this method relating to refueling operations, LNG is supplied to the marine vessel by connecting the LNG source to the vessel's refueling line via the refueling station's inlet pipe and subsequently supplying LNG to the LNG storage tank via the refueling line. Before the marine vessel arrives at the refueling facility, the refueling line is cooled to a temperature level corresponding to the LNG temperature level by recirculating LNG from the lower part of the LNG storage tank to the refueling line and then returning it to the LNG storage tank via the refueling line.

[0014] The basic configuration for fuel supply to a hydrogen-based power generation system would be to connect fuel-consuming units (such as multiple interconnected fuel cells) to a storage tank that can be filled externally. This system could be used, for example, in marine applications where the fuel cells serve as the power source for the vessel, the storage tank is located on board, and the fuel filling system is in a port or truck, or in a refueling system. Alternatively, the fuel-consuming units could be arranged to form a land-based power station, with fuel delivered to the station by truck or train. The same principle can even be applied to ordinary passenger cars, buses, or trucks.

[0015] One aspect to consider is the extremely low boiling point of liquefied gaseous fuels. LNG has a temperature of -163°C, which impacts the design of LNG fuel supply systems. Normal atmospheric temperatures are significantly higher than the boiling point of LNG, meaning that when associated with any non-cryogenic components such as fuel supply system parts, pipelines, valves, etc., at atmospheric temperatures, the liquid fuel will boil and rapidly transition to the gas phase. For economic and practical reasons, cryogenic conditions are limited to a minimum, such as to the storage tank and its vicinity (e.g., tank connection spaces). The tank is surrounded by valves, meaning any connections, such as fuel supply lines leading to or originating from the tank, are also equipped with valves. After filling the tank, the fuel supply system must be inertized. These fuel supply systems can be particularly long in the case of offshore vessels, where fuel supply pipelines can be tens or even hundreds of meters long. In the case of LNG, this inertization is accomplished using nitrogen. The gas phase temperature of nitrogen is suitable for this purpose, as nitrogen condenses at -196°C and freezes at -210°C. This means that if nitrogen is supplied to the pipeline after LNG, the nitrogen is still in the gas phase. However, the same methods and materials cannot be applied to hydrogen fuel supply systems. One of the key differences between liquid hydrogen and LNG is the boiling point of the liquid, and hydrogen has a boiling point of -252.87°C. This means that if nitrogen is supplied to the pipeline after liquefied hydrogen, it will condense or even freeze in the pipeline, which is most likely to cause problems.

[0016] The object of this invention is to provide an arrangement in a liquid hydrogen fuel supply system, which can be connected to a refueling station for supplying liquid hydrogen to the system. Another object of this invention is to provide a method in a liquid hydrogen fuel supply system, which can be connected to a refueling station for supplying liquid hydrogen to the system. Both this arrangement and this method represent a significant improvement in performance compared to prior art solutions. Summary of the Invention

[0017] The objectives of this invention can be essentially achieved as described below.

[0018] According to an embodiment of the present invention, a fuel tank arrangement structure is provided in a liquid hydrogen fuel supply system for storing and supplying hydrogen to a gas consumer, the system comprising:

[0019] -Inlet pipeline used to supply fuel to the storage tank,

[0020] - The inlet pipeline has a first valve located at the first end and a second valve located at the storage tank end.

[0021] - The inlet pipeline is provided with an inert gas flushing medium pipeline. A first end of the inert gas flushing medium pipeline is connected to the inlet pipeline downstream of the first valve, and a second end of the inert gas flushing medium pipeline is controllably connected to an inert gas source for performing inert gas flushing on the inlet pipeline.

[0022] The system also includes:

[0023] - The inlet pipeline is provided with a fuel gas flushing medium pipeline. The first end of the fuel gas flushing medium pipeline is controllably connected to the inlet pipeline downstream of the first valve, and the second end of the fuel gas flushing medium pipeline is connected to a gaseous hydrogen source to supply gaseous hydrogen to the inlet pipeline to perform a first flush on the inlet pipeline.

[0024] This provides an arrangement with significantly improved performance and inertization operations that can be performed efficiently and safely. It requires a specialized component arrangement suitable for these very harsh cryogenic freezing conditions. However, the arrangement largely utilizes features needed for other purposes, and the number of additional components is relatively small.

[0025] According to one embodiment, a method for filling a liquid hydrogen fuel supply system for storing and supplying liquid hydrogen to a gas consumer using this arrangement structure, the method comprising the following steps:

[0026] - A supply step, in which a predetermined amount of liquid hydrogen is supplied from the refueling station connection to the storage tank via an inlet line having a first valve at a first end and a second valve at the storage tank end, wherein the first valve is closed after the supply.

[0027] - An inertization step, which inertizes the inlet line by supplying inert gas via an inert gas flushing medium line controllably connected downstream of the first valve, the supplied inert gas flushing hydrogen from the inlet line into the storage tank.

[0028] Between the supply step and the inerting step, a fuel gas flushing step is performed, wherein gaseous hydrogen is supplied from a gaseous hydrogen source to the inlet line via a fuel gas flushing medium line connected to the inlet line downstream of the first valve, the gaseous hydrogen flushing the inlet line and simultaneously warming the inlet line.

[0029] According to an embodiment of the invention, the gaseous hydrogen source is a device for increasing the pressure and temperature of the gaseous hydrogen, and it is connected to or supplied by gaseous or liquid hydrogen in the storage tank. Thus, the same fuel already filled for consumption is the medium used for flushing, and it is first taken from the storage tank to the device for increasing pressure and temperature, and then directed to flush and warm the inlet line. The flushing gas can be taken from the gas space of the storage tank. A portion of the liquid hydrogen in the storage tank evaporates and forms so-called boil-off gas (or flash vapor). It is already in the gas phase, and the step of evaporating the liquid to the gas phase can be avoided. During the flushing operation, the warmed gas is returned to the storage tank. Using evaporated and heated liquid hydrogen for the fuel gas flushing operation and reintroducing it as gas into the storage tank increases the pressure in the storage tank more than using heated boil-off gas from the storage tank for the flushing operation. Therefore, using boil-off gas and then simply reintroducing the heated gas into the storage tank is a more economical alternative since the step of evaporating liquid hydrogen is avoided. However, for flushing, it is necessary to increase the pressure of the flushing gas by suitable means in any case. Otherwise, the pressure in both the inlet line and the fuel flushing medium line will be the same, and flushing will not occur.

[0030] Several alternatives exist for increasing the pressure and temperature of hydrogen and for the heater / evaporator used in flushing operations. One option is a main gas evaporator in a tank arrangement that uses the tank to evaporate either gaseous or liquid hydrogen as the gaseous hydrogen source. During normal operation, the main gas evaporator is used to evaporate and heat the liquid gas when the gas consumer uses fuel from the tank arrangement. Another alternative is a pressurized gaseous hydrogen source, which is a pressure accumulator evaporator. Used in pressurized tank arrangements, pressure accumulator evaporators are an option for pump-operated tank arrangements to increase and maintain sufficient pressure in the tank for the gas consumer during operation. Another possible hydrogen source for flushing operations is a pressure-increasing device, such as a pump, pressure accumulator, or the like. This choice of gaseous hydrogen source depends on the actual configuration of the system, and many configurations are possible.

[0031] According to this method, the inlet pipeline safety procedure is a two-step process. First, a fuel gas flush pushes any remaining liquid hydrogen into the storage tank and evaporates any possible trace amounts of residual liquid hydrogen, while also warming the inlet pipeline. The next step is an inert gas flush, which replaces the fuel gas in the inlet pipeline by pushing it into the storage tank. For both steps, the appropriate flushing volume and pressure are selected based on the actual configuration, inlet pipeline diameter, and length. The flushing pressure and flow rate need to be sufficient to move the medium forward of the flushing medium.

[0032] According to one embodiment of the invention, the inlet line is equipped with a temperature sensor (or multiple sensors) for determining the inlet line temperature. This feature enables temperature monitoring of the inlet line. For fuel gas flushing, a certain amount of liquid hydrogen has boiled or evaporated into a gaseous phase and been warmed to a predetermined temperature above Tn, where Tn is the condensation temperature of the inert gas. During fuel gas flushing, the temperature of the inlet line is monitored, and after it is determined that the inlet line temperature is above Tn, the fuel gas flushing medium line is shut off and flushing with inert gas can begin. It is useful for the operator to know whether the inlet line temperature is low enough that the inert gas will condense or freeze. In other words, fuel gas flushing advantageously continues until the inlet line temperature has first risen above the freezing temperature of the inert gas, and then above the condensation temperature of the inert gas. Only after this is it safe to introduce inert gas into the inlet line and flush it to an inert state so that there is no risk of the inlet line containing flammable or explosive amounts of residual fuel. The completion of inert gas flushing can be determined, for example, by measuring the concentration of inert gas in the tank end of the inlet line. The completion of the inerting phase can also be confirmed by considering that a certain amount of volume exchange has been completed. For example, if the amount of nitrogen used for flushing is, for instance, five times the volume of the inlet pipeline, this means that sufficient flushing has been performed, and the pipeline can be considered inerted. Nitrogen is the most suitable inerting gas because it is cheaper than other inerting gases, thus keeping operating costs low for power generation system operators. Other alternatives such as argon or helium can also be considered.

[0033] Exemplary embodiments of the invention presented in this patent application shall not be construed as limiting the applicability of the appended claims. The verb "comprising" is used in this patent application as an open-ended limitation and does not exclude the presence of features not listed. Unless otherwise expressly stated, the features set forth in the dependent claims can be freely combined with each other. Novel features considered to be characteristic of the invention are specifically set forth in the appended claims. Attached Figure Description

[0034] The invention will now be described with reference to the accompanying exemplary schematic diagrams, in which:

[0035] Figure 1 An example of a fuel supply system according to one embodiment of the present invention is shown;

[0036] Figure 2 Another fuel supply system according to another embodiment of the invention is illustrated.

[0037] List of reference numerals

[0038] 1. Fuel Supply System

[0039] 10 storage tanks

[0040] 100 Tank Connection Space

[0041] 11 Inlet Pipeline

[0042] 11a Inlet pipe leading to the gas space

[0043] 11a1 valve

[0044] 11b Inlet line to the liquid space

[0045] 11b1 valve

[0046] 111 First Valve

[0047] 112 Second Valve

[0048] 116 Temperature Sensor

[0049] 12. Outlet Pipeline

[0050] Valves 121, 122, 123, 124, 125, 126, 127, 128

[0051] 13 Inert gas flushing medium pipeline

[0052] 130 Inert gas source

[0053] 14 Fuel gas flushing medium pipeline

[0054] 15. Gaseous hydrogen source

[0055] 151 Pressure Accumulation Evaporator

[0056] 152 Main Gas Evaporator

[0057] 153 Fuel Pump

[0058] 8. Gas Consumer

[0059] Tn, the condensation temperature of inert gas

[0060] B Fueling station connector Detailed Implementation

[0061] Figure 1 The schematic depiction illustrates the arrangement of fuel storage tanks in a liquid hydrogen fuel supply system 1 for storing and supplying hydrogen to a gas consumer 8, the system comprising:

[0062] -Inlet pipeline 11 for supplying fuel to storage tank 10,

[0063] -Inlet pipeline 11 has a first valve 111 located at the first end and a second valve 112 located at the tank end.

[0064] - An inert gas flushing medium line 13 is provided for the inlet line 11. The first end of the inert gas flushing medium line 13 is connected to the inlet line 11 downstream of the first valve 111, and the second end of the inert gas flushing medium line 13 is controllably connected to an inert gas source 130 for performing inert gas flushing on the inlet line 11.

[0065] -The system also includes:

[0066] - The inlet line 11 is provided with a fuel gas flushing medium line 14, the first end of which is controllably connected to the inlet line 11 downstream of the first valve 111.

[0067] Furthermore, the second end of the fuel gas flushing medium line 14 is connected to a gaseous hydrogen source 15 to supply gaseous hydrogen to the inlet line 11, thereby performing a first flush on the inlet line 11.

[0068] According to one embodiment, a method for filling a liquid hydrogen fuel supply system 1 for storing and supplying liquid hydrogen to a gas consumer 8 using this arrangement structure includes the following steps:

[0069] - A predetermined amount of liquid hydrogen is supplied from a fuel station (not shown) connected to fuel station connector B to a storage tank 10 via an inlet line 11, the inlet line 11 having a first valve 111 at a first end and a second valve 112 at a storage tank end, and the first valve 111 is closed after the supply.

[0070] - The inlet line 11 is inertized by supplying inert gas via an inert gas flushing medium line 13 that is controllably connected downstream of the first valve 111, and the supplied inert gas flushes hydrogen from the inlet line 11 into the storage tank 10.

[0071] Between the supply step and the inertization step, a fuel gas flushing step is performed, wherein gaseous hydrogen is supplied from a gaseous hydrogen source 15 to the inlet line 11 via a fuel gas flushing medium line 14 connected downstream of the first valve 111 to the inlet line 11, the gaseous hydrogen flushing the inlet line 11 and simultaneously warming the inlet line 11.

[0072] exist Figure 1 In this configuration, the liquid hydrogen fuel supply system 1 is arranged such that the gaseous hydrogen source 15 is a device for increasing the pressure and temperature of the gaseous hydrogen, and it is connected to or supplied with gaseous or liquid hydrogen from the storage tank 10. Regarding the gaseous hydrogen source 15, reference numeral 15 is used in the accompanying drawings. Figure 1 The symbol illustratively refers to the initial point in the fuel gas flushing medium pipeline 14; the actual device outlet can be connected to this initial point. For example, in... Figure 1 In the attached diagram, reference numeral 15 points to the intersection where either a main gas evaporator 152 or a pressure accumulation evaporator 151 can be optionally connected. Using this evaporator device, a certain amount of liquid hydrogen is evaporated into a gaseous phase and warmed (or only if the hydrogen is already in the gaseous phase) to a predetermined temperature above Tn, where Tn is the condensation temperature of the inert gas. Evaporation and subsequent heating can be powered, for example, by an external heat source such as a gas consumer cooling system, as in... Figure 1 The reference diagram illustrates the heat input (H_in) and heat output (H_out) of the heating fluid. For this purpose, electric heating can also be used. The electric heater can be integrated into the evaporator to provide heat directly at the evaporator, or integrated into the heating fluid circuit to provide additional heating to the fluid before it enters the evaporator. Thus, the added electric heater solves the problem that there may not be enough heat available in the heating fluid at the time the fuel filling operation is complete, and the fuel line should be flushed and inertized.

[0073] During the fuel gas flushing step, warm gaseous hydrogen is supplied to the inlet line 11 downstream of the first valve 111. The gaseous hydrogen flushes the inlet line 11 while simultaneously warming it. The fuel gas flushing pushes any remaining liquid hydrogen in the inlet line 11 to the storage tank 10 and evaporates any possible small amount of residual liquid hydrogen. The operator of the system can select whether the end of the inlet line 11 leads to the gas space via inlet line 11a or to the liquid space via inlet line 11b by opening and closing appropriate valves 11a1 and 11b1. For fuel gas flushing, the portion of the flushing line located between valves 111 and 112 is relevant in pushing any remaining liquid hydrogen in the inlet line 11 to the storage tank 10. It is recommended to open only valve 11a1, as the medium to be flushed consists of hydrogen in both liquid and gas phases. It is inconvenient to flush the liquid portion leading to the liquid space in the storage tank; instead, flushing is performed on the gaseous portion of the inlet line 11a leading to the gas space in the storage tank. At the end of this step, the inlet line temperature is higher than the condensation temperature Tn of the inert gas, and it is filled with fuel gas, i.e., gaseous hydrogen. A temperature sensor 116 or multiple temperature sensors along the inlet line 11 are provided to determine the temperature of the inlet line 11. Additionally, advantageously, the fuel gas flushing medium line 14 is equipped with a temperature sensor 116. Using the temperature information, it can be determined whether the inlet line 11 is in a safe condition and ready for the next process step, i.e., inert gas flushing. When the temperature of the inlet line 11 is being monitored and after it is determined that the temperature of the inlet line 11 is higher than Tn, the fuel gas flushing medium line 14 is shut off, and flushing with inert gas can begin.

[0074] In inert gas flushing, inert gas is supplied to inlet line 11 via inert gas flushing medium line 13, which is controllably connected to inlet line 11 downstream of first valve 111. The supplied inert gas flushes hydrogen from inlet line 11 into storage tank 10. Here, inert gas flushing replaces fuel gas in inlet line 11 by pushing it into storage tank 10. Therefore, the pressure and flow rate of the inert gas need to be selected to allow flushing to occur.

[0075] exist Figure 1This paper presents one embodiment of a liquid hydrogen fuel supply system 1 for storing and supplying hydrogen to a gas consumer 8. During normal operation of the system, gas is supplied from an isolated storage tank 10 via an outlet line 12 to one of the evaporators, either to a pressure accumulating evaporator 151 and back to the storage tank 10, or to a main gas evaporator 152, and then further supplied to the gas consumer 8, such as an engine or fuel cell. The pressure accumulating evaporator is used to evaporate the liquefied gas and supply it back to the storage tank in order to maintain a sufficiently high pressure in the storage tank for system operation. The pressure accumulating evaporator operates based on the need to increase the pressure in the storage tank.

[0076] According to Figure 1 In this system, the generation of fuel flushing gas can be carried out in several ways, described here without particular priority. The first option is to use a pressure accumulator evaporator. With this option, valve 121 of the outlet line 12 from tank 10 is open, and valve 122 of the line leading to the main gas evaporator 152 is closed. Heating fluid is arranged to flow through the pressure accumulator 151. Valves 123 and 127 are open, allowing circulation through the pressure accumulator 151 for evaporating liquid hydrogen. With valves 128, 125, and 126 closed and valves 124 and 141 open, the evaporated gas flows to the fuel gas flushing medium line 14. With valves 141 and 112 open and valve 111 closed, the fuel flushing gas flows towards the tank flushing inlet line 11. The second option is to use the main gas evaporator 152 in conjunction with liquid hydrogen from tank 10. Unlike the first option, valve 122 of the line leading to the main gas evaporator 152 is opened, while valve 123, which allows circulation through the pressure build-up evaporator 151, is closed. The heating fluid is then arranged to flow through the main gas evaporator 152. With valve 81 leading to the gas consumer 8 closed and valves 125 and 124 open while valve 127 is closed, fuel flushing gas is generated and directed to line 11 in the same manner as in the first option. The third option uses gaseous hydrogen, i.e., so-called vaporized gas from the storage tank 10. By opening valves 126 and 128 and closing valves 121, 123, and 127, gaseous hydrogen is directed to the main gas evaporator 152 to increase pressure and temperature. With valve 81 leading to the gas consumer 8 closed and valves 125 and 124 open while valve 127 is closed, fuel flushing gas is generated and directed to line 11 in the same manner as in the first and second options.

[0077] It will be clear to those skilled in the art that, in Figure 1 In some implementations, both the pressure accumulation evaporator 151 and the main gas evaporator 152 can be used as parallel evaporators to generate fuel flushing gas.

[0078] Figure 1 The fuel storage tank arrangement includes a tank connection space 100 to separate the connections for entering and exiting the storage tank 10. The fuel supply system is equipped with... Figure 1 and Figure 2 The valves in the diagram are indicated by standard symbols 121, 122, 123, 124, 125, 126, 127, 128, and 81. Those skilled in the art will understand which valves need to be closed, which need to be opened, or which need to be regulated in order to perform the functions of the system.

[0079] exist Figure 2 The image shows the arrangement of fuel storage tanks in a liquid hydrogen fuel supply system 1 for storing and supplying hydrogen to a gas consumer 8. This system includes:

[0080] -Inlet pipeline 11 for supplying fuel to storage tank 10,

[0081] -Inlet pipeline 11 has a first valve 111 located at the first end and a second valve 112 located at the tank end.

[0082] - An inert gas flushing medium line 13 is provided for the inlet line 11. The first end of the inert gas flushing medium line 13 is connected to the inlet line 11 downstream of the first valve 111, and the second end of the inert gas flushing medium line 13 is controllably connected to an inert gas source 130 for flushing the inlet line 11 with inert gas.

[0083] - The inlet line 11 is provided with a fuel gas flushing medium line 14, the first end of which is controllably connected to the inlet line 11 downstream of the first valve 111.

[0084] Furthermore, the second end of the fuel gas flushing medium line 14 is connected to a gaseous hydrogen source 15 to supply gaseous hydrogen to the inlet line 11, thereby performing a first flush on the inlet line 11. This embodiment of system 1 is similar to the one described above. Figure 1 The difference between the implementation described herein and the one described above is that the fuel supply system 1 uses a fuel pump 153 to pressurize the fuel for the main gas evaporator 152, therefore the piping and Figure 1 It differs slightly from the above due to the lack of a pressure buildup evaporator. Otherwise, the features and functions remain consistent with those already described. Figure 1 The descriptions are the same.

[0085] According to Figure 2In this system, fuel flushing gas is generated as follows. First, valve 121 of the outlet line 12 from storage tank 10 is opened, valve 126 is closed, and fuel is directed towards the open valve 122 and then to the line leading to the main gas evaporator 152 using fuel pump 153. Heating fluid is arranged to flow through the main gas evaporator 152, which evaporates and heats the liquid hydrogen. With valve 81 leading to gas consumer 8 closed and valves 124 and 141 open, the evaporated gas flows to the fuel gas flushing medium line 14. With valves 141 and 112 open and valve 111 closed, the fuel flushing gas flows towards the flushing inlet line 11 of storage tank 10. Additionally, using… Figure 2 In this implementation, vapor from the storage tank can be used. Therefore, valves 126 and 122 are open while valve 121 is closed, and fuel pump 153 is not used. In other respects, the features and functions remain consistent with those described above. Figure 1 The descriptions are the same.

[0086] While the invention has been described herein by way of examples in conjunction with what is now considered the preferred embodiment, it is to be understood that the invention is not limited to the disclosed embodiments, but is intended to cover various combinations or variations of the features of the invention and a number of other applications included within the scope of the invention as defined in the appended claims. Details mentioned in any of the foregoing embodiments may be used in conjunction with another embodiment where it is technically feasible to combine them with that embodiment.

Claims

1. A fuel tank arrangement in a liquid hydrogen fuel supply system (1) for storing and supplying hydrogen to a gas consumer (8), the system including an inlet line (11) for supplying fuel to a storage tank (10). wherein The inlet pipeline (11) has a first valve (111) at a first end and a second valve (112) at a tank end. The inlet pipeline (11) is provided with an inert gas flushing medium pipeline (13). The first end of the inert gas flushing medium pipeline (13) is connected to the inlet pipeline (11) downstream of the first valve (111), and the second end of the inert gas flushing medium pipeline (13) is controllably connected to an inert gas source (130) for performing inert gas flushing on the inlet pipeline (11). The inlet pipeline (11) is characterized by having a fuel gas flushing medium pipeline (14), the first end of which is controllably connected to the inlet pipeline (11) downstream of the first valve (111), and the second end of which is connected to a gaseous hydrogen source (15) to supply gaseous hydrogen to the inlet pipeline (11) to perform a first flush on the inlet pipeline (11).

2. The fuel tank arrangement in a liquid hydrogen fuel supply system (1) according to claim 1, characterized in that, The gaseous hydrogen source (15) is a device for increasing the pressure and temperature of gaseous hydrogen, and the gaseous hydrogen source (15) is connected to the storage tank (10) or supplied by gaseous or liquid hydrogen in the storage tank (10).

3. The fuel tank arrangement in a liquid hydrogen fuel supply system (1) according to claim 1 or 2, characterized in that, The gaseous hydrogen source (15) is the main gas evaporator (152).

4. The fuel tank arrangement in a liquid hydrogen fuel supply system (1) according to claim 1 or 2, characterized in that, The gaseous hydrogen source (15) is a pressure accumulation evaporator (151).

5. The fuel tank arrangement in a liquid hydrogen fuel supply system (1) according to claim 1 or 2, characterized in that, The inlet pipeline (11) is also provided with a temperature sensor (116) for determining the temperature of the inlet pipeline (11).

6. The fuel storage tank arrangement structure in the liquid hydrogen fuel supply system (1) according to claim 1 or 2, characterized in that, The fuel storage tank arrangement structure is provided with a storage tank connection space (100) for separating the connection between the tank (10) and the entrance.

7. The fuel storage tank arrangement structure in the liquid hydrogen fuel supply system (1) according to claim 1 or 2, characterized in that, The fuel storage tank arrangement includes a pressure increasing device, which is a pump or a pressure accumulator.

8. The fuel storage tank arrangement structure in the liquid hydrogen fuel supply system (1) according to claim 1, characterized in that, The inert gas is nitrogen.

9. A method for filling a liquid hydrogen fuel supply system (1) for storing and supplying liquid hydrogen to a gas consumer (8), the method comprising the steps of: A supply step, which supplies a predetermined amount of liquid hydrogen from the refueling station connection (B) to the storage tank (10) via an inlet line (11), the inlet line (11) having a first valve (111) at a first end and a second valve (112) at the storage tank end, and after the supply, closing the first valve (111); and An inertization step is performed by supplying inert gas to the inlet line (11) via an inert gas flushing medium line (13) connected in a controllable manner downstream of the first valve (111), the supplied inert gas flushing hydrogen from the inlet line (11) into the storage tank (10). The method is characterized by further comprising the following steps: Between the supply step and the inertization step, a fuel gas flushing step is performed, wherein gaseous hydrogen is supplied from a gaseous hydrogen source (15) to the inlet line (11) via a fuel gas flushing medium line (14) connected downstream of the first valve (111), the gaseous hydrogen flushing the inlet line (11) and simultaneously warming the inlet line (11).

10. The method for filling the liquid hydrogen fuel supply system (1) for storing and supplying liquid hydrogen to the gas consumer (8) according to claim 9, characterized in that, During the fuel gas flushing, a certain amount of liquid hydrogen is evaporated into a gas phase and warmed to a predetermined temperature above Tn, where Tn is the condensation temperature of the inert gas.

11. The method for filling a liquid hydrogen fuel supply system (1) for storing and supplying liquid hydrogen to a gas consumer (8) according to claim 9 or 10, characterized in that, The temperature of the inlet line (11) is monitored and, after determining that the temperature of the inlet line (11) is higher than Tn, the fuel gas flushing medium line (14) is shut off and flushing with inert gas can begin.

12. The method for filling a liquid hydrogen fuel supply system (1) for storing and supplying liquid hydrogen to a gas consumer (8) according to claim 9 or 10, characterized in that, The completion of inert gas flushing is determined by measuring the concentration of the inert gas in the inlet pipeline (11) at the tank end.

13. The method for filling a liquid hydrogen fuel supply system (1) for storing and supplying liquid hydrogen to a gas consumer (8) according to claim 9 or 10, characterized in that, The gaseous hydrogen source (15) is the storage tank (10), the main gas evaporator (152) that evaporates a certain amount of hydrogen, or the pressure accumulation evaporator (151).

14. The method for filling a liquid hydrogen fuel supply system (1) for storing and supplying liquid hydrogen to a gas consumer (8) according to claim 9 or 10, characterized in that, The fuel gas flushing pushes any remaining liquid hydrogen in the inlet line (11) into the storage tank (10) and evaporates any possible small amount of residual liquid hydrogen.

15. The method for filling a liquid hydrogen fuel supply system (1) for storing and supplying liquid hydrogen to a gas consumer (8) according to claim 9 or 10, characterized in that, Inert gas flushing replaces the fuel gas by pushing the fuel gas in the inlet line (11) into the storage tank (10).

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