An overpressure hydrogen utilization device for hydrogen storage tank

Abstract

The present invention relates to the field of hydrogen storage technology, specifically to an overpressure hydrogen utilization device for a hydrogen storage tank. A first temperature sensor and a second temperature sensor are used to measure the surface and internal temperatures of the hydrogen storage tank, respectively. A pressure sensor is connected to the hydrogen storage tank. A quantitative discharge unit includes a hydrogen filling valve, a hydrogen filling flowmeter, a solenoid valve, a first shut-off valve, a pressure reducing valve, and a hydrogen discharge mass flow controller sequentially arranged on a pipeline. The pipeline between the hydrogen storage tank and the hydrogen filling flowmeter and the solenoid valve is connected. The control unit is electrically connected to the first temperature sensor, the second temperature sensor, the pressure sensor, the hydrogen filling flowmeter, the solenoid valve, and the hydrogen discharge mass flow controller. This solves the problem that when a hydrogen storage tank is in a low-temperature fully charged state, if the hydrogen storage tank's heating system fails, the temperature suddenly rises, and its equilibrium pressure also rises, which can easily exceed the design pressure of the tank body and cause great harm.

Description

Technical Field

[0001] The present invention relates to the technical field of hydrogen storage, and in particular to an overpressure hydrogen utilization device for a hydrogen storage tank. Background Art

[0002] Over a decade of experience accumulated through diverse research, development, and demonstration projects has confirmed that fuel cells and hydrogen technologies play a significant role in green energy systems, reducing dependence on fossil fuels and curbing pollutant and greenhouse gas emissions. A future hydrogen-based society will soon become a reality, with hydrogen becoming one of the primary energy carriers.

[0003] Metal hydride storage can operate at very low pressures, has very good energy efficiency, and provides a safe method of hydrogen storage. Therefore, a lot of research has been done in the past few years to develop this technology. For any hydrogen storage application, the optimal system design will vary depending on the operating environment, acceptable cost, and safety and performance requirements. The metal hydride storage tank is filled with metal hydrogen storage materials. Common metal hydrogen storage materials are LaNi5, ZrMn2, TiMn2, TiFe, Mg2Ni, vanadium-based solid solutions, etc. The hydrogen charging and dehydration characteristics of such materials are usually inferred from the pressure-composition-temperature (PCT) isotherm, which describes the dependence of the hydrogen equilibrium pressure on the amount of hydrogen introduced into or extracted from the hydride at a fixed temperature.

[0004] Due to the inherent characteristics of metal hydrides, metal hydride storage devices usually need to absorb hydrogen at low temperatures and release hydrogen at high temperatures. After absorbing hydrogen at low temperatures, the hydrogen storage tank is fully charged. According to the material PCT curve, when the hydrogen storage tank stores C1 amount of hydrogen at temperature T1, when the temperature rises to T2, its pressure will inevitably exceed P max Therefore, according to the PCT curve of the material, the remaining hydrogen must be discharged to C2 to ensure that the pressure in the tank is lower than P at T2 temperature. max The most likely potential risk of a hydrogen storage tank is when the tank is fully charged at low temperature. If the tank's heating system fails at this time, the temperature suddenly rises, and its equilibrium pressure also rises. The overpressure phenomenon generated by this state is also the basic principle of metal hydride hydrogen compressors. The overpressure generated by this abnormal temperature can easily exceed the design pressure of the tank, causing great harm.

[0005] Traditional overpressure hydrogen utilization devices usually use mechanical safety valves, that is, they automatically open when the pressure exceeds the set pressure of the safety valve. Such overpressure hydrogen utilization devices are widely used in pressure vessels, pressure pipelines and other places, and the use scenarios of hydrogen storage tanks are usually special. The emission of hydrogen requires precise control and post-processing. Since the metal hydrogen storage material is filled inside, the latter is restricted by the PCT isotherm curve, and its temperature-pressure change trend is difficult to predict according to Charles' law. The pressure will rise rapidly, and the required emission volume is much larger than the emission volume required for compressed gas. The mechanical safety valve will continue to open and release a large amount of hydrogen. Therefore, it is necessary to predict and determine the pressure and the required emission volume of hydrogen under abnormal temperature conditions, so as to achieve accurate emission of hydrogen under abnormal temperature conditions of the hydrogen storage tank and utilize the hydrogen.

[0006] The document with patent application number 201910060601.4 discloses a temperature-compensated alloy hydrogen storage and supply system, in which the metal hydrogen storage container adopts an external immersion heat exchange form, and does not consider the quantitative overpressure discharge and utilization of the hydrogen storage tank under abnormal temperature conditions. Moreover, there is currently no discharge and utilization device designed for the characteristics of the hydrogen storage material of the hydrogen storage tank. Summary of the Invention

[0007] In view of this, it is necessary to provide an overpressure hydrogen utilization device for a hydrogen storage tank to solve the problem that when the hydrogen storage tank is in a low-temperature fully filled state, once the heating system of the hydrogen storage tank fails, the temperature suddenly rises, and its equilibrium pressure will increase accordingly, which may easily exceed the design pressure of the tank body and cause great harm.

[0008] The present invention provides an overpressure hydrogen utilization device for a hydrogen storage tank, comprising:

[0009] A temperature monitoring unit, comprising a first temperature sensor and a second temperature sensor, wherein the first temperature sensor and the second temperature sensor are used to measure the surface temperature and the internal temperature of the hydrogen storage tank respectively;

[0010] A pressure monitoring unit, comprising a pressure sensor connected to the hydrogen storage tank and configured to detect the pressure within the hydrogen storage tank;

[0011] A quantitative discharge unit, comprising a hydrogen charging valve, a hydrogen charging flow meter, a solenoid valve, a first shut-off valve, a hydrogen charging flow meter, a pressure reducing valve, and a hydrogen discharge mass flow controller sequentially arranged on a pipeline, wherein the pipeline between the hydrogen storage tank and the hydrogen charging flow meter and the solenoid valve is connected; and

[0012] A control unit is electrically connected to the first temperature sensor, the second temperature sensor, the pressure sensor, the solenoid valve, and the hydrogen degassing mass flow controller.

[0013] In some embodiments, the first temperature sensor is fixed to the outer surface of the hydrogen storage tank via a thermal insulation sponge.

[0014] In some embodiments, a temperature measuring sleeve is reserved on the hydrogen storage tank, the temperature measuring sleeve is filled with flexible insulation material, and the second temperature sensor is inserted into the temperature measuring sleeve to measure the internal temperature of the hydrogen storage tank.

[0015] In some embodiments, a second stop valve is further connected between the solenoid valve and the hydrogen degassing mass flow controller, and the second stop valve is connected in parallel with the first stop valve and the pressure reducing valve.

[0016] In some embodiments, a centralized hydrogen remover is further provided at the end of the hydrogen degassing mass flow controller.

[0017] In some embodiments, the hydrogen storage tank is provided with a tank port valve, the pressure sensor is connected to the hydrogen storage tank via the tank port valve, and the tank port valve remains open.

[0018] In some embodiments, the hydrogen storage tank is an alloy hydrogen storage tank.

[0019] In some embodiments, the hydrogen storage tank is filled with a metal hydrogen storage material, and the metal hydrogen storage material is one or more of LaNi5, ZrMn2, TiMn2, TiFe, Mg2Ni or a vanadium-based solid solution.

[0020] In some embodiments, the control unit is used to substitute the detected initial temperature, pressure, cumulative hydrogen filling flow and other parameters into the PCT curve based on the PCT curve of the hydrogen storage material used for the hydrogen storage tank at different temperatures, predict and determine the pressure and the required amount of hydrogen discharged under abnormal temperature conditions, and realize pressure monitoring and precise discharge of the hydrogen storage tank under abnormal temperature conditions by opening and closing the solenoid valve.

[0021] In some embodiments, the control unit includes a host computer and a PLC connected to the host computer, and the PLC is electrically connected to the first temperature sensor, the second temperature sensor, the pressure sensor, the hydrogen charging flow meter, the solenoid valve, and the hydrogen degassing mass flow controller.

[0022] Compared with the prior art: the present invention provides an overpressure hydrogen utilization device for a hydrogen storage tank, wherein a first temperature sensor and a second temperature sensor are used to measure the surface and internal temperatures of the hydrogen storage tank respectively, a pressure sensor is connected to the hydrogen storage tank, and the pressure sensor is used to detect the pressure in the hydrogen storage tank, and a quantitative discharge unit includes a hydrogen charging valve, a hydrogen charging flow meter, a solenoid valve, a first stop valve, a pressure reducing valve and a hydrogen discharge mass flow controller which are sequentially arranged on the pipeline, the pipeline between the hydrogen storage tank and the hydrogen charging flow meter and the solenoid valve is connected, and the control unit is electrically connected to the first temperature sensor, the second temperature sensor, the pressure sensor, the hydrogen charging flow meter, the solenoid valve and the hydrogen discharge mass flow controller; data is collected and monitored by the control unit, and the pressure and the required hydrogen discharge amount under abnormal temperature conditions are predicted and determined, thereby controlling the opening and closing of the solenoid valve to realize pressure monitoring and precise discharge of the alloy hydrogen storage tank under abnormal temperature conditions, overcoming the shortcomings of traditional pressure monitoring and overpressure hydrogen utilization devices, and effectively improving the safety of hydrogen storage tank use. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The present invention will be further described below with reference to the accompanying drawings and examples.

[0024] Figure 1 This is a structural schematic diagram of an overpressure hydrogen utilization device for a hydrogen storage tank according to the present invention;

[0025] Figure 2 It is a schematic diagram based on the PCT isotherm. DETAILED DESCRIPTION

[0026] The preferred embodiments of the present invention will be described in detail below in conjunction with the accompanying drawings, wherein the accompanying drawings constitute a part of this application and are used together with the embodiments of the present invention to illustrate the principles of the present invention, and are not used to limit the scope of the present invention.

[0027] In this specific embodiment, an overpressure hydrogen utilization device for a hydrogen storage tank includes a temperature monitoring unit 1, a pressure monitoring unit 2, a quantitative discharge unit 3 and a control unit 4, wherein the temperature monitoring unit 1 includes a first temperature sensor 11 and a second temperature sensor 12, which are respectively used to measure the surface and internal temperatures of the hydrogen storage tank A; the pressure monitoring unit 2 includes a pressure sensor 21, which is connected to the hydrogen storage tank and is used to detect the pressure inside the hydrogen storage tank A; the quantitative discharge unit 3 includes a hydrogen charging valve 31, a hydrogen charging flowmeter 32, a solenoid valve 33, a first stop valve 34, a pressure reducing valve 35 and a hydrogen degassing mass flow controller 36 arranged in sequence on the pipeline, and the pipeline between the hydrogen storage tank A and the hydrogen charging flowmeter 32 and the solenoid valve 33 is connected; the control unit 4 is electrically connected to the first temperature sensor 11, the second temperature sensor 12, the pressure sensor 21, the hydrogen charging flowmeter 32, the solenoid valve 33 and the hydrogen degassing mass flow controller 36.

[0028] In addition, the first temperature sensor 11 is fixed to the outer surface of the hydrogen storage tank through an insulating sponge. A temperature measuring sleeve is reserved on the hydrogen storage tank, and the temperature measuring sleeve is filled with flexible insulating material. The second temperature sensor 12 is inserted into the temperature measuring sleeve to measure the internal temperature of the hydrogen storage tank.

[0029] On the basis of the above solution, a second stop valve 37 is further connected between the solenoid valve 33 and the hydrogen degassing mass flow controller 36 , and the second stop valve 37 is connected in parallel with the first stop valve 34 and the pressure reducing valve 35 .

[0030] It should be noted that a centralized hydrogen remover 38 or a hydrogen storage tank group is further provided at the end of the hydrogen release mass flow controller 36 , wherein the hydrogen storage tank group includes at least two hydrogen storage tanks, specifically, the hydrogen storage tanks are alloy hydrogen storage tanks.

[0031] On the basis of the above solution, the pressure monitoring unit 2 further includes a tank port valve 22, which is provided on the hydrogen storage tank. The pressure sensor 21 is connected to the hydrogen storage tank via the tank port valve 22, and the tank port valve 22 remains open.

[0032] It should be noted that the hydrogen storage tank is filled with a metal hydrogen storage material, which is a vanadium-based solid solution. Of course, it can also be one or more of LaNi5, ZrMn2, TiMn2, TiFe or Mg2Ni.

[0033] Furthermore, the control unit 4 is used to substitute the detected initial temperature, pressure, cumulative hydrogen charging flow and other parameters into the PCT curve based on the PCT curve of the metal hydrogen storage material at different temperatures in the hydrogen storage tank, predict and determine the pressure and the required hydrogen discharge amount under abnormal temperature conditions, and realize pressure monitoring and precise discharge under abnormal temperature conditions of the hydrogen storage tank by opening and closing the solenoid valve 33.

[0034] Specifically, the control unit 4 includes a host computer 41 and a PLC 42 connected to the host computer. The PLC 42 is electrically connected to the first temperature sensor 11, the second temperature sensor 12, the pressure sensor 21, the hydrogen charging flow meter 32, the solenoid valve 33 and the hydrogen degassing mass flow controller 36.

[0035] In one embodiment, referring to Figure 1 and Figure 2 As shown, the present invention provides a pressure monitoring and overpressure hydrogen utilization device for an alloy hydrogen storage tank. Taking a vanadium-based solid solution hydrogen storage alloy tank as an example (the maximum hydrogen storage capacity of the metal hydrogen storage material in the alloy tank is 2.4wt%, and the design pressure of the alloy hydrogen storage tank is 5.0MPa), the operation method of the pressure monitoring and overpressure hydrogen utilization device is explained.

[0036] 1. Monitor the pressure inside the alloy hydrogen storage tank.

[0037] Example 1:

[0038] When the temperature of the circulating water bath of the alloy hydrogen storage tank is 10℃ and the cumulative hydrogen storage capacity of the hydrogen filling flow meter is 2.10wt%, its pressure sensor shows that the equilibrium pressure is 6.0MPa. When the circulating water system fails, the surface temperature and the temperature inside the alloy hydrogen storage tank are measured and the average temperature reaches 30℃. Substitute the hydrogen storage capacity and temperature values ​​into Figure 2 Curve, according to Figure 2 The PCT curve shows that the equilibrium pressure of the current hydrogen amount at this temperature is 8.5MPa, which does not exceed the maximum tank pressure of 10MPa. The current state is maintained unchanged by the PCT (pressure-composition-temperature) feedback control unit, and the solenoid valve does not need to be opened.

[0039] Example 2:

[0040] When the circulating water bath temperature of the alloy hydrogen storage tank is 10℃ and the cumulative hydrogen storage capacity of the hydrogen filling flow meter is 2.10wt%, its equilibrium pressure is 6.0MPa. When the circulating water system fails, the average temperature of the alloy hydrogen storage tank reaches 50℃ through the measurement of the surface temperature and the temperature inside the tank. Figure 2 Curve, according to Figure 2The PCT curve shows that the equilibrium pressure of the current hydrogen amount at this temperature is 11.5 MPa, which exceeds its maximum pressure of 10.0 MPa. The PCT (pressure-composition-temperature) feedback control unit requires the discharge solenoid valve to open.

[0041] Example 3:

[0042] When the circulating water bath temperature of the alloy hydrogen storage tank is 10℃ and the cumulative hydrogen storage capacity of the hydrogen filling flow meter is 2.30wt%, its equilibrium pressure is 6.5MPa. When the circulating water system fails, the average temperature of the alloy hydrogen storage tank reaches 40℃ through the measurement of the surface temperature and the temperature inside the tank. Figure 2 Curve, according to Figure 2 The PCT curve shows that the equilibrium pressure of the current hydrogen amount at this temperature is 12 MPa, which exceeds its maximum pressure of 10.0 MPa. The PCT (pressure-composition-temperature) feedback control unit requires the discharge solenoid valve to open.

[0043] 2. Quantitative centralized overpressure discharge and utilization of hydrogen in alloy hydrogen storage tanks.

[0044] Example 4:

[0045] When the water bath temperature of the alloy hydrogen storage tank is 10℃ and the hydrogen storage capacity is 2.10wt%, its equilibrium pressure is 6.0MPa. When the circulating water system fails, the surface temperature and the temperature inside the alloy hydrogen storage tank are measured, and its average temperature reaches 50℃. At this temperature, the equilibrium hydrogen content at 10.0MPa is 1.38wt%. Substitute the hydrogen storage capacity and temperature values ​​into Figure 2 Curve, according to Figure 2 The PCT curve indicates that the equilibrium pressure of the current hydrogen content at this temperature is 11.5 MPa, exceeding its maximum pressure of 10.0 MPa. The PCT (pressure-composition-temperature) feedback control unit requires the discharge solenoid valve to open. The overpressure hydrogen is quantitatively discharged into the centralized hydrogen dissipator through the first shut-off valve, the pressure reducing valve, and the hydrogen discharge mass flow controller. The accumulated hydrogen discharge input from the hydrogen discharge mass flow controller is fed into the PCT (pressure-composition-temperature) feedback control unit. When the accumulated hydrogen discharge reaches 2.10 wt% - 1.38 wt% = 0.72 wt%, the solenoid valve closes, completing centralized discharge in one go and ensuring the safety of the hydrogen supply system.

[0046] Example 5:

[0047] When the water bath temperature of the alloy hydrogen storage tank is 10℃ and the hydrogen storage capacity is 2.30wt%, its equilibrium pressure is 6.5MPa. When the circulating water system fails, the surface temperature and the temperature inside the alloy hydrogen storage tank are measured, and its average temperature reaches 40℃. At this temperature, the equilibrium hydrogen content at 10.0MPa is 1.59wt%. Substitute the hydrogen storage capacity and temperature values ​​into Figure 2 Curve, according to Figure 2 The PCT curve indicates that the equilibrium pressure of the current hydrogen content at this temperature is 12.0 MPa, exceeding its maximum pressure of 10.0 MPa. The PCT (pressure-composition-temperature) feedback control unit requires the discharge solenoid valve to open. The overpressure hydrogen is discharged through a second shut-off valve and a hydrogen discharge mass flow controller into the alloy hydrogen storage tank group. The latter uses the accumulated value of the hydrogen charging flow meter to determine the hydrogen storage capacity after charging. The accumulated hydrogen discharge input from the hydrogen discharge mass flow controller is fed through the PCT (pressure-composition-temperature) feedback control unit. When the accumulated hydrogen discharge value reaches 2.30 wt% - 1.59 wt% = 0.71 wt%, the solenoid valve closes, completing centralized discharge in one go and ensuring the safety of the hydrogen supply system.

[0048] The beneficial effects are:

[0049] Compared with the prior art: the present invention provides an overpressure hydrogen utilization device for a hydrogen storage tank, wherein a first temperature sensor and a second temperature sensor are used to measure the surface and internal temperatures of the hydrogen storage tank respectively, a pressure sensor is connected to the hydrogen storage tank, and the pressure sensor is used to detect the pressure in the hydrogen storage tank, and a quantitative discharge unit comprises a hydrogen charging valve, a hydrogen charging flow meter, a solenoid valve, a first stop valve, a hydrogen charging flow meter, a pressure reducing valve and a hydrogen discharge mass flow controller which are sequentially arranged on the pipeline, the pipeline between the hydrogen storage tank and the hydrogen charging flow meter and the solenoid valve is connected, and the control unit is electrically connected to the first temperature sensor, the second temperature sensor, the pressure sensor, the solenoid valve and the hydrogen discharge mass flow controller; data is collected and monitored by the control unit, and the pressure and the required hydrogen discharge amount under abnormal temperature conditions are predicted and determined, thereby controlling the opening and closing of the solenoid valve to realize pressure monitoring and precise discharge of the alloy hydrogen storage tank under abnormal temperature conditions, overcoming the shortcomings of traditional pressure monitoring and overpressure hydrogen utilization devices, and effectively improving the safety of hydrogen storage tank use.

[0050] The above description is only a preferred specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by any technician familiar with this technical field within the technical scope disclosed by the present invention should be covered by the scope of protection of the present invention.

Claims

1. An overpressure hydrogen utilization device for a hydrogen storage tank, characterized in that: include: A temperature monitoring unit, comprising a first temperature sensor and a second temperature sensor, wherein the first temperature sensor and the second temperature sensor are used to measure the surface temperature and the internal temperature of the hydrogen storage tank respectively; A pressure monitoring unit, comprising a pressure sensor connected to the hydrogen storage tank and configured to detect the pressure within the hydrogen storage tank; A quantitative discharge unit, comprising a hydrogen charging valve, a hydrogen charging flow meter, a solenoid valve, a first shut-off valve, a pressure reducing valve, and a hydrogen discharge mass flow controller sequentially arranged on a pipeline, wherein the pipeline between the hydrogen storage tank and the hydrogen charging flow meter and the solenoid valve is connected; and a control unit electrically connected to the first temperature sensor, the second temperature sensor, the pressure sensor, the hydrogen charging flow meter, the solenoid valve, and the hydrogen degassing mass flow controller; The control unit is used to substitute the detected initial temperature, pressure, cumulative hydrogen charging flow rate and other parameters into the PCT curve based on the PCT curve of the hydrogen storage material for the hydrogen storage tank at different temperatures, predict and determine the pressure and required hydrogen discharge amount under abnormal temperature conditions, and realize pressure monitoring and precise discharge of the hydrogen storage tank under abnormal temperature conditions by opening and closing the solenoid valve; The control unit includes a host computer and a PLC connected to the host computer. The PLC is electrically connected to a first temperature sensor, a second temperature sensor, a pressure sensor, a hydrogen charging flow meter, a solenoid valve, and a hydrogen degassing mass flow controller.

2. The overpressure hydrogen utilization device for a hydrogen storage tank according to claim 1, characterized in that: The first temperature sensor is fixed to the outer surface of the hydrogen storage tank through a heat-insulating sponge.

3. The overpressure hydrogen utilization device for a hydrogen storage tank according to claim 1, characterized in that: A temperature measuring sleeve is reserved on the hydrogen storage tank, and the temperature measuring sleeve is filled with flexible heat insulation material. The second temperature sensor is inserted into the temperature measuring sleeve to measure the internal temperature of the hydrogen storage tank.

4. The overpressure hydrogen utilization device for a hydrogen storage tank according to claim 1, characterized in that: A second stop valve is further connected between the solenoid valve and the hydrogen degassing mass flow controller, and the second stop valve is connected in parallel with the first stop valve and the pressure reducing valve.

5. The overpressure hydrogen utilization device for a hydrogen storage tank according to claim 1, characterized in that: A centralized hydrogen remover is also provided at the end of the hydrogen release mass flow controller.

6. The overpressure hydrogen utilization device for a hydrogen storage tank according to claim 1, characterized in that: The hydrogen storage tank is provided with a tank port valve, the pressure sensor is connected to the hydrogen storage tank via the tank port valve, and the tank port valve is kept in an open state.

7. The overpressure hydrogen utilization device for a hydrogen storage tank according to claim 1, characterized in that: The hydrogen storage tank is an alloy hydrogen storage tank.

8. The overpressure hydrogen utilization device for a hydrogen storage tank according to claim 1, characterized in that: The hydrogen storage tank is filled with metal hydrogen storage material, and the metal hydrogen storage material is one or more of LaNi5, ZrMn2, TiMn2, TiFe, Mg2Ni or vanadium-based solid solution.

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