Liquid hydrogen vaporization system

Abstract

To provide a technique which can effectively use the cold heat energy of liquid hydrogen when producing hydrogen gas from liquid hydrogen.SOLUTION: A liquid hydrogen vaporization system 100 in one embodiment comprises: a heat exchanger 51 for exchanging heat between liquid hydrogen and gaseous air; an air-liquid separator 52 for separating air-liquid two-phase hydrogen output from the heat exchanger 51 into gas and liquid; a liquid air drum 54 in which liquid air output from the heat exchanger 51 is held; a condenser 53 for condensing the gaseous air evaporated from the liquid air drum 54 using the liquid hydrogen separated by the gas-liquid separator 52; and a rectification tower 55 provided between the liquid air drum 54 and the condenser 53, and performing rectification through contact of the gas evaporated from the liquid air drum 54 with the liquid which is condensed by the condenser 53 and is made to flow back.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present disclosure relates to a liquid hydrogen vaporization system.

Background Art

[0002] Conventionally, a technique for generating hydrogen gas by vaporizing liquid hydrogen through heat exchange with the atmosphere is known (see Patent Document 1).

Prior Art Documents

Patent Documents

[0003] <000​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​The system includes a rectification section provided between the holding section and the condensing section, which performs rectification by contact between the gas evaporating from the holding section and the liquid condensed and refluxed in the condensing section. A liquid hydrogen vaporization system is provided. [Effects of the Invention]

[0007] According to the above-described embodiment, the cold energy of liquid hydrogen can be effectively utilized when generating hydrogen gas from liquid hydrogen. [Brief explanation of the drawing]

[0008] [Figure 1] This is a diagram showing a first example of the configuration of a liquid hydrogen vaporization system. [Figure 2] This figure shows a second example of the configuration of a liquid hydrogen vaporization system. [Figure 3] This is a diagram showing an example of the configuration of a hydrogen gas filling system. [Modes for carrying out the invention]

[0009] The embodiments will be described below with reference to the drawings.

[0010] [First example of a liquid hydrogen vaporization system] Referring to Figure 1, a first example of the liquid hydrogen vaporization system 100 according to this embodiment will be described.

[0011] Figure 1 shows a first example of the configuration of the liquid hydrogen vaporization system 100.

[0012] The liquid hydrogen vaporization system 100 includes a liquid hydrogen storage tank 10, a liquid hydrogen low-pressure pump 20, an air blower 30, an air dryer 40, and a cold box refrigeration tank 50.

[0013] The liquid hydrogen vaporization system 100 effectively utilizes the cold energy (thermal energy) of the liquid hydrogen in the liquid hydrogen storage tank 10, then vaporizes the liquid hydrogen and outputs it to the outside as hydrogen gas (gaseous hydrogen).

[0014] The liquid hydrogen storage tank 10 stores liquid hydrogen.

[0015] The liquid hydrogen storage tank 10 is connected to the cold box cold storage tank 50 by a pipe L1. Thereby, the liquid hydrogen storage tank 10 supplies liquid hydrogen to the cold box cold storage tank 50 through the pipe L1. The pipe L1 has a heat insulation structure.

[0016] The liquid hydrogen low-pressure pump 20 is arranged on the pipe L1. Specifically, the pipe L1 includes pipes L11 and L12. The liquid hydrogen low-pressure pump 20 is connected to the liquid hydrogen storage tank 10 through the pipe L11 and is connected to the cold box cold storage tank 50 through the pipe L12. The liquid hydrogen low-pressure pump 20 sucks in liquid hydrogen from the pipe L11, boosts the pressure of the liquid hydrogen, and discharges it to the pipe L12. The boosted liquid hydrogen is supplied to the cold box cold storage tank 50 through the pipe L12. Thereby, by adjusting the degree of pressure boost by the liquid hydrogen low-pressure pump 20, the operating pressure in the condenser 53 described later, that is, the saturation temperature on the liquid hydrogen side, can be adjusted. The pressure boosting level of the liquid hydrogen in the liquid hydrogen low-pressure pump 20 is carried out within a pressure range in the liquefaction region when the hydrogen gas whose temperature has risen in the heat exchanger 51 expands against the gas-liquid separator 53.

[0017] The air blower 30 sucks in the atmosphere that becomes the raw material to be component-separated as described later by the cold heat energy of the liquid hydrogen, boosts the pressure, and discharges it to the pipe L2.

[0018] The air dryer 40 is connected to the pipe L2 and dehumidifies and dries the compressed air supplied through the pipe L2. The compressed air dehumidified and dried by the air dryer 40 is output to the pipe L3, and the dehumidified and dried air is supplied to the cold box cold storage tank 50 through the pipe L3.

[0019] The cold box cold storage tank 50 includes a heat exchanger 51, a gas-liquid separator 52, a condenser 53, a liquid air drum 54, and a rectification column 55.

[0020] The heat exchanger 51 (an example of the first heat exchange section) performs heat exchange between the liquid hydrogen supplied to the cold box cold storage tank 50 through the pipe L12 and the compressed air supplied to the cold box cold storage tank 50 through the pipe L3. Specifically, the pipe L12 is connected to the input pipe LI1 inside the cold box cold storage tank 50, and liquid hydrogen is supplied to the heat exchanger 51 through the input pipe LI1. Also, the pipe L3 is connected to the input pipe LI2 inside the cold box cold storage tank 50, and compressed air is supplied to the heat exchanger 51 through the input pipe LI2.

[0021] The heat exchanger 51 transfers heat energy from the compressed air to the liquid hydrogen, outputs the hydrogen in the gas-liquid two-phase state where a part has been vaporized to the intermediate pipe LM1, and outputs the liquefied air (liquid air) to the intermediate pipe LM2.

[0022] The gas-liquid separator 52 (an example of the gas-liquid separation section) is connected to the intermediate pipe LM1 and separates the hydrogen in the gas-liquid two-phase state supplied through the intermediate pipe LM1 into liquid hydrogen and gaseous hydrogen (hydrogen gas). The gas-liquid separator 52 outputs the hydrogen gas separated at its upper part to the output pipe LO1. Thereby, the hydrogen gas taken out of the cold box cold storage tank 50 through the output pipe LO1 can be used for a predetermined purpose (for example, refer to FIG. 3 described later).

[0023] The condenser 53 (an example of the condensation section) uses the liquid hydrogen separated at the lower part of the gas-liquid separator 52 to condense the gas supplied through the rectification column 55 and reflux it to the rectification column 55.

[0024] The liquid air drum 54 (an example of the holding section) is connected to the intermediate pipe LM2 and holds the liquid air supplied through the intermediate pipe LM2.

[0025] The rectification column 55 (an example of a rectification section) is installed between the condenser 53 and the liquid air drum 54. Rectification of the air evaporating from the liquid air drum 54 is performed by contact between the air evaporating from the liquid air drum 54 and the liquid refluxed from the condenser 53. As a result, a component with a relatively low boiling point, specifically very high-purity liquid nitrogen, can be produced at the top of the rectification column 55, and a component with a relatively high boiling point, specifically very high-oxygen liquid air, can be accumulated in the liquid air drum 54.

[0026] An output tube LO2 is connected to the top of the rectification column 55, and liquid nitrogen is output to the output tube LO2. This allows the liquid nitrogen taken out of the cold box refrigeration tank 50 through the output tube LO2 to be used for a predetermined purpose.

[0027] An output tube LO3 is connected to the liquid air drum 54, and liquid air with a very high oxygen concentration is output to the output tube LO3. This allows the liquid air with a very high oxygen concentration, which is taken out to the outside of the cold box refrigeration tank 50 through the output tube LO3, to be used for a predetermined purpose.

[0028] Thus, in this example, when the liquid hydrogen vaporization system 100 vaporizes liquid hydrogen by heat exchange with air, it can utilize the cold energy of the liquid hydrogen to separate the liquefied air from the liquid air into liquid nitrogen and liquid air with a very high oxygen concentration.

[0029] [Second example of a liquid hydrogen vaporization system] Next, with reference to Figure 2, a second example of the liquid hydrogen vaporization system 100 according to this embodiment will be described.

[0030] The following explanation will focus on content that differs from the first example described above, and explanations of content that is the same as or corresponds to the first example may be simplified or omitted.

[0031] Figure 2 shows a second example of the configuration of the liquid hydrogen vaporization system 100.

[0032] The liquid hydrogen vaporization system 100 includes a heat exchanger 51, a gas-liquid separator 52, a condenser 53, a liquid air drum 54, and a rectification column 55, similar to the first example described above. However, unlike the first example described above, the liquid hydrogen vaporization system 100 also includes a heat exchanger 56.

[0033] The gas-liquid separator 52 is connected to the intermediate pipe LM3 and outputs the hydrogen gas separated at its upper end to the intermediate pipe LM3.

[0034] The heat exchanger 56 (an example of a second heat exchange section) performs heat exchange between compressed air supplied through the input pipe LI2 and hydrogen gas supplied through the intermediate pipe LM3, outputting hydrogen gas to the output pipe LO1 and compressed air to the intermediate pipe LM4. This allows the hydrogen gas to be extracted to the outside of the cold box refrigeration tank 50 with its temperature further restored (increased).

[0035] The heat exchanger 51 is connected to the intermediate pipe LM4 and performs heat exchange between compressed air supplied through the intermediate pipe LM4 and liquid hydrogen supplied through the input pipe LI1.

[0036] Thus, in this example, the liquid hydrogen vaporization system 100 can output hydrogen gas at a higher temperature to the outside by exchanging heat between hydrogen gas and compressed air.

[0037] [Application examples of liquid hydrogen vaporization systems] Next, with reference to Figure 3, an example of the application of the liquid hydrogen vaporization system 100 will be described.

[0038] Figure 3 shows an example of the application of the liquid hydrogen vaporization system 100. Specifically, Figure 3 shows an example of the hydrogen gas filling system 1.

[0039] Note that in Figure 3, some components of the liquid hydrogen vaporization system 100, such as the liquid hydrogen low-pressure pump 20, air blower 30, and air dryer 40, are not shown.

[0040] As shown in Figure 3, the hydrogen gas filling system 1 includes a liquid hydrogen vaporization system 100, a hydrogen gas compression unit 200, a high-pressure hydrogen gas storage unit 300, and a dispenser 400.

[0041] The liquid hydrogen vaporization system 100 receives liquid hydrogen transported by a tanker truck RL into a liquid hydrogen storage tank 10, and generates and outputs hydrogen gas from the liquid hydrogen in the liquid hydrogen storage tank 10 in a cold box refrigeration tank 50.

[0042] The hydrogen gas compression unit 200 includes a low-pressure hydrogen gas storage tank 210 and a compressor 220.

[0043] The low-pressure hydrogen gas storage tank 210 stores hydrogen gas at a relatively low pressure, which is output from the liquid hydrogen vaporization system 100.

[0044] The compressor 220 compresses the hydrogen gas supplied from the low-pressure hydrogen gas storage tank 210 and outputs hydrogen gas that has been pressurized to a relatively high pressure.

[0045] The high-pressure hydrogen gas output from the hydrogen gas compression unit 200 (compressor 220) is supplied to at least one of the high-pressure hydrogen gas storage unit 300 and the dispenser 400.

[0046] The high-pressure hydrogen gas storage unit 300 stores the high-pressure hydrogen gas output from the hydrogen gas compression unit 200 and supplies the high-pressure hydrogen gas to the dispenser 400. For example, the high-pressure hydrogen gas storage unit 300 includes multiple hydrogen gas storage tanks that have very high pressure resistance and are capable of storing high-pressure hydrogen gas.

[0047] The dispenser 400 fills the hydrogen tank TNK of the vehicle VCL with high-pressure hydrogen gas supplied from at least one of the hydrogen gas compression unit 200 and the high-pressure hydrogen gas storage unit 300. The vehicle VCL is, for example, a fuel cell vehicle equipped with a fuel cell capable of generating electricity using hydrogen gas as fuel.

[0048] The dispenser 400 includes the precooler 410.

[0049] The precooler 410 cools the high-pressure hydrogen gas supplied from at least one of the hydrogen gas compression unit 200 and the high-pressure hydrogen gas storage unit 300 before filling the hydrogen tank TNK, and outputs the cooled high-pressure hydrogen gas toward the hydrogen tank TNK. This makes it possible to suppress the temperature of the hydrogen tank TNK to below a predetermined standard.

[0050] The precooler 410 includes a cooling unit 411 and a refrigerator 412.

[0051] The cooling unit 411 cools the high-pressure hydrogen gas supplied from at least one of the hydrogen gas compression unit 200 and the high-pressure hydrogen gas storage unit 300.

[0052] The refrigerator 412 supplies cold energy to the cooling unit 411 to cool the hydrogen gas.

[0053] Alternatively, a bypass path may be provided to the hydrogen gas output from the liquid hydrogen vaporization system 100 to the dispenser 400, so that the hydrogen gas output from the liquid hydrogen vaporization system 100 is directly mixed with the hydrogen gas that is filled into the hydrogen tank TNK from the dispenser 400. This allows the temperature of the hydrogen gas being filled into the hydrogen tank TNK from the dispenser 400 to be lowered by the cryogenic hydrogen gas output from the liquid hydrogen vaporization system 100. In this case, the precooler 410 may be omitted.

[0054] In this way, the liquid hydrogen vaporization system 100 can be applied to the hydrogen gas filling system 1.

[0055] [Effect] Next, the operation of the liquid hydrogen vaporization system 100 according to this embodiment will be described.

[0056] In this embodiment, the liquid hydrogen vaporization system 100 comprises a heat exchanger 51, a gas-liquid separator 52, a liquid air drum 54, a condenser 53, and a rectification column 55. Specifically, the heat exchanger 51 performs heat exchange between liquid hydrogen and gaseous air. The gas-liquid separator 52 separates the gaseous two-phase hydrogen output from the heat exchanger 51 into gas and liquid. The liquid air output from the heat exchanger 51 is held in the liquid air drum 54. The condenser 53 uses the liquid hydrogen separated in the gas-liquid separator 52 to condense the gaseous air evaporating from the liquid air drum 54. The rectification column 55 is provided between the liquid air drum 54 and the condenser 53, and performs rectification by contact between the gas evaporating from the liquid air drum 54 and the liquid condensed in the condenser 53 and refluxed.

[0057] As a result, the liquid hydrogen vaporization system 100 utilizes the thermal energy of the liquid hydrogen separated in the gas-liquid separator 52 to convert liquid air into high-purity liquid nitrogen and liquid air with a high oxygen concentration. It can be separated and supplied externally. Therefore, the liquid hydrogen vaporization system 100 can effectively utilize the cold energy of liquid hydrogen when generating hydrogen gas from liquid hydrogen.

[0058] Furthermore, in this embodiment, the liquid hydrogen vaporization system 100 may also include a second heat exchange unit that performs heat exchange between gaseous hydrogen (hydrogen gas) output from the gas-liquid separator 52 and gaseous air. The heat exchanger 51 may also perform heat exchange between gaseous air output from the heat exchanger 56 and liquid hydrogen.

[0059] This allows the liquid hydrogen vaporization system 100 to output hydrogen gas to the outside at a higher temperature.

[0060] Although embodiments have been described in detail above, this disclosure is not limited to these specific embodiments, and various modifications and changes are possible within the scope of the gist described in the claims. [Explanation of Symbols]

[0061] 1. Hydrogen gas filling system 10 Liquid hydrogen storage tanks 20 pumps 30 blowers 40 Hair Dryer 50 Cold Box Insulated Tanks 51 Heat exchanger 52 Gas-liquid separator 53 Condenser 54 Liquid Air Drum 55 Rectification tower 56 Heat exchanger 100 Liquid Hydrogen Vaporization System 200 Hydrogen gas compression section 210 Low-pressure hydrogen gas storage tank 220 Compressor 300 High-Pressure Hydrogen Gas Storage Unit 400 Dispenser 410 Precooler 411 Cooling section 412 Refrigeration unit LI1, LI2 input tubes LO1~LO3 Output Tubes RL Laurie TNK Hydrogen Tank VCL Vehicle

Claims

1. A first heat exchange unit that performs heat exchange between liquid hydrogen and gaseous air, A gas-liquid separation unit separates the gas-liquid two-phase hydrogen output from the first heat exchange unit into gas and liquid, A holding section that holds the liquid air output from the first heat exchange section, A condensing unit that uses the liquid hydrogen separated in the gas-liquid separation unit to condense the gaseous air evaporating from the holding unit, The system includes a rectification section provided between the holding section and the condensing section, which performs rectification by contact between the gas evaporating from the holding section and the liquid condensed and refluxed in the condensing section. Liquid hydrogen vaporization system.

2. The system includes a second heat exchange unit that performs heat exchange between gaseous hydrogen output from the gas-liquid separation unit and gaseous air. The first heat exchange unit performs heat exchange between gaseous air output from the second heat exchange unit and liquid hydrogen. The liquid hydrogen vaporization system according to claim 1.

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