Micro-channel solid hydrogen storage thermal management system

Abstract

The invention innovatively provides a micro-channel solid hydrogen storage thermal management system which comprises a pressure controller, a safety valve, a circulating pump, a ball valve, a micro-channel reactor, a three-way ball valve and a cooler, and the specific structure is as follows: the safety valve, the circulating pump, the ball valve, the micro-channel reactor, the three-way ball valve and the cooler are sequentially communicated through pipelines to form a loop; a hydrogen outlet of the pressure controller is communicated with a pipeline between the safety valve and the cooler, a hydrogen inlet of the pressure controller is connected with a hydrogen source, and one port of the three-way ball valve is a hydrogen outlet.

Description

Technical Field

[0001] The present invention relates to the technical field of hydrogen storage systems, and more particularly to a microchannel solid-state hydrogen storage thermal management system. Background Art

[0002] The use of hydrogen energy is one of the effective ways to solve the global energy shortage and environmental pollution. Hydrogen is not only high in calorific value, green and pollution-free, but also has a wide range of sources. It can be produced through renewable energy such as electrolysis of water and biomass to produce "green hydrogen". In the process of hydrogen energy utilization, safe and efficient hydrogen storage technology has become one of the important links in its commercial application. At present, hydrogen storage technologies mainly include high-pressure gaseous hydrogen storage, low-temperature liquid hydrogen storage, and solid-state hydrogen storage based on chemical adsorption of hydrogen storage materials. Among them, solid-state hydrogen storage has become one of the key development directions of hydrogen storage technology in the future due to its advantages such as high volume hydrogen storage density, strong safety and stability, low storage pressure, and convenience for large-scale storage and transportation. The core of solid-state hydrogen storage technology is high-density, lightweight hydrogen storage materials and high-performance hydrogen storage devices. At present, in the research on hydrogen storage materials, its mass hydrogen storage density is close to the theoretical value and cannot break through the theoretical limit. However, when hydrogen storage materials are applied to hydrogen storage systems, their hydrogen absorption and desorption amount and reaction rate are still restricted by the reaction heat transfer performance in the fixed bed reactor. Therefore, the thermal management technology of solid-state hydrogen storage systems has become the core of its efficient hydrogen absorption and desorption. At present, the thermal management technologies of solid-state hydrogen storage systems mainly include the following categories:

[0003] (1) The reactor dissipates heat through the outer wall

[0004] The reaction heat of hydrogen storage material absorption and desorption process is significant, so the absorption / desorption process needs to continuously discharge or supply heat to the hydrogen storage material reaction bed to prevent the temperature of the reaction bed from rising or falling, causing the reaction to reach equilibrium, so as to promote the continuous and efficient absorption and desorption reaction. Natural convection heat exchange between the reactor wall and the air or water / oil in the thermostatic bath is one of the simplest thermal management methods, but the natural convection heat transfer coefficient is low, so the heat transfer performance of the reactor is poor. In addition, a shell-and-tube heat exchanger is arranged on the periphery of the reactor, and forced convection heat exchange between the heat transfer fluid and the reactor wall can effectively enhance the heat transfer performance of the reactor and accelerate the absorption and desorption reaction rate. However, the hydrogen storage system of this type of thermal management method needs to be equipped with a heat exchange fluid circulation cooling / heating subsystem, and the system structure is relatively complex.

[0005] (2) Heat exchanger in reactor

[0006] The heat exchanger inside the reactor is similar to the external shell-and-tube heat exchanger, and heat is exchanged by forced convection between the heat exchange fluid in the heat exchanger and the hydrogen storage material reaction bed. At present, the structures of heat exchangers inside the reactor mainly include straight tube heat exchangers, spiral tube heat exchangers, microchannel heat exchangers, etc. In addition, heat transfer can be further enhanced by adding fins to the heat exchanger. With the evolution of heat exchangers from straight tubes to microchannels, their heat exchange area continues to increase, but their structures continue to become more complex, resulting in difficulties in the processing and design of such reactors, and it is difficult to ensure the safety and stability of operation. For example, the expansion and deformation of the hydrogen storage material reaction bed during the hydrogen absorption and desorption process can easily lead to the damage of the micro-pipes in the microchannel heat exchanger. In addition, the hydrogen storage system of the heat exchanger inside the reactor also needs to be equipped with a heat exchange fluid circulation cooling / heating system, which complicates the system structure.

[0007] (3) Reactor equipped with phase change material for heat transfer and storage

[0008] Phase change materials, as an excellent heat transfer and storage medium, have been used in solid-state hydrogen storage systems to manage reactor heat. The heat absorption, heating, melting, heat release, cooling, and solidification behaviors of phase change materials not only achieve effective transfer of reaction heat, but also achieve the recovery of reaction heat, which can effectively improve the energy utilization rate of hydrogen storage systems. Currently, phase change materials are mainly integrated on the periphery of the reactor to transfer heat through the reactor wall. Solid-state hydrogen storage devices that only use phase change materials for thermal management simplify the system structure, but because the metal hydride hydrogen storage material has a large enthalpy of hydrogen absorption and desorption reactions, a large amount of phase change materials is required to completely absorb the reaction heat, which not only increases the cost of the device, but also causes a serious loss of system volume or mass hydrogen storage density.

[0009] Therefore, in summary, metal hydride hydrogen storage devices based on various thermal management methods still have some defects and are still a certain distance away from actual industrial applications. Summary of the invention

[0010] In view of the deficiencies in the prior art, an object of the present invention is to provide a microchannel solid-state hydrogen storage thermal management system to overcome the above-mentioned defects in the prior art.

[0011] To achieve the above object, the present invention provides the following technical solutions:

[0012] A microchannel solid-state hydrogen storage thermal management system includes a pressure controller, a safety valve, a circulation pump, a ball valve, a microchannel reactor, a three-way ball valve, and a cooler. The specific structure is as follows: the safety valve, the circulation pump, the ball valve, the microchannel reactor, the three-way ball valve, and the cooler are connected in sequence through pipelines to form a loop, the hydrogen outlet of the pressure controller is connected to the pipeline between the safety valve and the cooler, the hydrogen inlet of the pressure controller is connected to a hydrogen source, and one port of the three-way ball valve is a hydrogen outlet.

[0013] Preferably, the microchannel reactor is provided with a closed container consisting of a stainless steel flange cover installed on a stainless steel tank body, a sealing gasket is arranged between the stainless steel flange cover and the stainless steel tank body, and the stainless steel tank body and the stainless steel flange cover are sealed by the sealing gasket and fastening bolts; a hydrogen outlet and a temperature sensor are welded on the stainless steel flange cover, a pressure sensor is connected at the hydrogen outlet through a three-way joint, and the lower end of the temperature sensor extends into the hydrogen storage material reaction bed in the stainless steel tank body.

[0014] Preferably, a heating layer is arranged on the periphery of the stainless steel tank body to make the interior of the reactor reach the initial reaction temperature state before the hydrogen absorption reaction and to provide a reaction heat source during the hydrogen release reaction, and the heating layer is wrapped with an insulation layer.

[0015] Preferably, the hydrogen inlet is welded to the lower side of the stainless steel tank body of the microchannel reactor, one end of which extends into the interior of the stainless steel tank body and is connected to the stainless steel tank body, and the other end of which extends to the outside of the insulation layer, so that the hydrogen can flow fully through the interior of the reactor through the bottom air intake and top air outlet.

[0016] Preferably, the reaction bed in the microchannel reactor is a compressed block of hydrogen storage material powder, which is stacked in the microchannel reactor through stainless steel supports. There are gaps between the compressed blocks of hydrogen storage material powder and the inner wall of the stainless steel tank of the microchannel reactor, and between the compressed blocks of hydrogen storage material powder, providing abundant channels for hydrogen flow and mass transfer.

[0017] Preferably, the hydrogen storage material powder compact uses AB5 type or Mg-based hydrogen storage alloy powder compact.

[0018] Preferably, hydrogen with a pressure higher than that of the hydrogen absorption reaction enters the system through a pressure controller, and the pressure controller controls the hydrogen flow rate according to a preset hydrogen absorption pressure, and maintains the hydrogen in the system at a set pressure value through dynamic feedback regulation; when the ball valve is open, the hydrogen entering the system enters the microchannel reactor through a circulation pump; the microchannel reactor provides the initial temperature conditions for the hydrogen absorption reaction through an outer heating layer, and the microchannel reactor starts the hydrogen absorption reaction process; since the hydrogen absorption reaction is exothermic, the hydrogen in the microchannel reactor absorbs heat and the temperature rises; when the three-way ball valve connects the reactor and the cooler, the high-temperature hydrogen flows out of the microchannel reactor to the cooler for cooling, and the reaction heat brought out of the hydrogen from the microchannel reactor is discharged from the system; since the hydrogen is consumed by the hydrogen absorption reaction in the microchannel reactor, the hydrogen pressure decreases after flowing out of the microchannel reactor and the cooler, and the pressure controller connected to the system adjusts the hydrogen flow rate to restore the hydrogen pressure in the system to a preset value, and the hydrogen enters the next cycle under the action of the circulation pump.

[0019] Preferably, after the hydrogen storage reaction is completed, the ball valve and the three-way ball valve are closed to achieve hydrogen storage in the microchannel reactor in a stable and closed state; during the hydrogen release reaction process, the microchannel reactor provides a reaction heat source through the peripheral heating layer, and when the hydrogen release reaction temperature is reached in the microchannel reactor, the three-way ball valve is connected to the microchannel reactor and the hydrogen outlet to start the hydrogen release reaction process.

[0020] Preferably, when the hydrogen pressure in the gas circuit is higher than the set pressure value of the safety valve, the safety valve is in an open state and discharges hydrogen to the outside of the system.

[0021] The beneficial effects of the present invention are as follows: since the enthalpy of the hydrogen absorption and desorption reaction of the metal hydride hydrogen storage material is relatively high, when applied to the solid hydrogen storage system of the present invention, the reaction heat can be discharged or supplied to the hydrogen storage material reaction bed in time during the hydrogen absorption / desorption process in the fixed bed reactor, so as to prevent the temperature of the reaction bed from rising or falling and causing the reaction to reach an equilibrium state, so as to promote the continuous and efficient conduct of the hydrogen absorption and desorption reaction; in the hydrogen absorption process of the present invention, the high-pressure hydrogen enters the hydrogen storage system through the pressure controller, and the pressure controller can control the hydrogen flow rate according to the set hydrogen absorption reaction pressure, and the hydrogen pressure change in the system is dynamically feedback-regulated during the hydrogen circulation process, so that the hydrogen in the system is kept near the set hydrogen absorption pressure value, so as to realize the hydrogen absorption reaction under a stable pressure; in the system of the present invention, the hydrogen realizes a circulation flow under the action of the circulation pump, and the hydrogen flowing into the reactor can not only provide the hydrogen storage material with hydrogen absorption reaction working fluid, but also discharge the hydrogen absorption reaction heat from the reactor through forced convection in the reactor. The high-temperature hydrogen flowing out of the reactor is cooled by the cooler to enter the next cycle, so as to realize the continuous discharge of the hydrogen absorption reaction heat in the reactor and the continuous and efficient conduct of the reaction. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a structural principle diagram of a microchannel solid-state hydrogen storage thermal management system of the present invention.

[0023] Figure 2 It is a schematic diagram of a microchannel reactor in the solid-state hydrogen storage system of the present invention.

[0024] Figure numerals: 1. pressure controller; 2. safety valve; 3. circulation pump; 4. ball valve; 5. microchannel reactor; 51. hydrogen outlet; 52. pressure sensor; 53. temperature sensor; 54. sealing gasket; 55. fastening bolts; 56. stainless steel flange cover; 57. insulation layer; 58. heating layer; 59. hydrogen inlet; 510. stainless steel tank body; 511. hydrogen storage material powder compact; 512. stainless steel bracket; 6. three-way ball valve; 7. cooler. DETAILED DESCRIPTION

[0025] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0026] It should be noted that when a component is referred to as being "fixed to" another component, it may be directly on the other component or there may also be a component centered. When a component is considered to be "connected to" another component, it may be directly connected to the other component or there may also be a component centered. When a component is considered to be "set on" another component, it may be directly set on the other component or there may also be a component centered. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only.

[0027] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0028] The embodiments of the present invention are further described in detail below with reference to the accompanying drawings:

[0029] See also Figure 1 The present invention proposes a microchannel solid-state hydrogen storage thermal management system, which mainly includes a pressure controller 1, a safety valve 2, a circulation pump 3, a ball valve 4, a microchannel reactor 5, a three-way ball valve 6, and a cooler 7. The specific structure is as follows: the safety valve 2, the circulation pump 3, the ball valve 4, the microchannel reactor 5, the three-way ball valve 6, and the cooler 7 are connected in sequence through pipelines to form a loop, the hydrogen outlet of the pressure controller 1 is connected to the pipeline between the safety valve 2 and the cooler 7, the hydrogen inlet of the pressure controller 1 is connected to a hydrogen source, and one port of the three-way ball valve 6 is a hydrogen outlet.

[0030] See also Figure 2In a microchannel solid-state hydrogen storage thermal management system of the present invention, a microchannel reactor 5 is provided with a closed container consisting of a stainless steel tank body 510 with a stainless steel flange cover 56 installed thereon, a sealing gasket 54 is arranged between the stainless steel flange cover 56 and the stainless steel tank body 510, and the stainless steel tank body 510 and the stainless steel flange cover 56 are sealed by the sealing gasket 54 and the fastening bolts 55. A hydrogen outlet 51 and a temperature sensor 53 are welded on the stainless steel flange cover 56, and a pressure sensor 52 is connected to the hydrogen outlet 51 through a three-way joint, and the lower end of the temperature sensor 53 extends into the hydrogen storage material powder compact 511 in the stainless steel tank body 510, and the pressure sensor 52 and the temperature sensor 53 are respectively used to monitor the temperature and pressure state changes in the microchannel reactor 5 during the hydrogen absorption and desorption process. A heating layer 58 is arranged on the periphery of the stainless steel tank body 510, which is used to make the hydrogen storage material reaction bed reach the initial reaction temperature state before the hydrogen absorption reaction starts and to provide a reaction heat source during the hydrogen desorption reaction. The heating layer 58 is wrapped with a thermal insulation layer 57 to reduce the heat loss during the operation of the heating layer 58. The hydrogen inlet 59 is welded to the lower side of the stainless steel tank 510 of the microchannel reactor 5, one end of which extends to the inside of the stainless steel tank 510 and is connected to the stainless steel tank 510, and the other end of which extends to the outside of the insulation layer 57, so that the hydrogen can fully flow through the reactor through the bottom air intake and the top air outlet. The hydrogen storage material reaction bed in the microchannel reactor 5 is a plurality of hydrogen storage material powder compacts 511, such as: using LaNi5 or Mg-based alloy hydrogen storage material powder compacts, which can not only prevent the material from pulverizing and expanding during the cyclic absorption and release of hydrogen, but also improve the effective thermal conductivity and volume hydrogen storage density of the reaction bed. The hydrogen storage material powder compacts 511 are stacked in the microchannel reactor 5 through stainless steel brackets 512, and there are gaps between the hydrogen storage material powder compacts 511 and the inner wall of the stainless steel tank 510 of the microchannel reactor 5, and between the hydrogen storage material powder compacts 511, which can provide abundant channels for hydrogen flow and mass transfer.

[0031] like Figure 1-Figure 2 As shown, the working process of a microchannel solid-state hydrogen storage thermal management system of the present invention is as follows:

[0032] Hydrogen gas higher than the hydrogen absorption reaction pressure (greater than 1.0MPa, such as 1.2MPa) enters the system at a certain hydrogen pressure (1.0MPa) through the pressure controller 1. The pressure controller 1 controls the hydrogen flow rate according to the preset pressure (1.0MPa), and keeps the hydrogen in the system near the set pressure value through dynamic feedback regulation. When the ball valve 4 is open, the hydrogen gas entering the system enters the microchannel reactor 5 through the circulation pump 3. The microchannel reactor 5 provides the initial temperature conditions for the hydrogen absorption reaction through the peripheral heating layer 58. The microchannel reactor 5 starts the hydrogen absorption reaction process at a certain temperature and hydrogen pressure (such as LaNi5 hydrogen storage material at 20°C and 1.0MPa, MgH2 hydrogen storage material at 300°C and 1.0MPa). Since the hydrogen absorption reaction is exothermic, the hydrogen in the microchannel reactor 5 absorbs heat and the temperature rises. When the three-way ball valve 6 connects the reactor 5 and the cooler 7, the high-temperature hydrogen flows out of the microchannel reactor 5 to the cooler 7 for cooling, and the reaction heat brought out of the microchannel reactor 5 is discharged from the system.

[0033] Since hydrogen is consumed by the hydrogen absorption reaction in the microchannel reactor 5, the hydrogen pressure decreases after flowing out of the microchannel reactor 5 and the cooler 7. At this time, the pressure controller 1 connected to the system adjusts the hydrogen flow rate to restore the hydrogen pressure in the system to the preset value, and the hydrogen enters the next cycle under the action of the circulation pump 3. Therefore, the circulation of hydrogen in the system not only provides the hydrogen absorption reaction working medium of the hydrogen storage material in the microchannel reactor 5, but also realizes the effective thermal management of the microchannel reactor 5. After the hydrogen storage reaction is completed, the ball valve 4 and the three-way ball valve 6 can be closed to realize the hydrogen storage of the microchannel reactor 5 in a stable and closed state. In the process of hydrogen release reaction, the microchannel reactor 5 can provide a reaction heat source through the peripheral heating layer 58. When a certain hydrogen release reaction temperature is reached in the microchannel reactor 5 (such as LaNi5 hydrogen storage material above 50°C, MgH2 hydrogen storage material above 350°C), the three-way ball valve 6 is connected to the microchannel reactor 5 and the hydrogen outlet, and the hydrogen release reaction process can be started. In addition, a safety valve 2 is configured in the system. When the hydrogen pressure in the gas circuit is higher than the set pressure value of the safety valve, the safety valve is in an open state and discharges hydrogen to the outside of the system to prevent the microchannel reactor 5, pipelines and other components from bursting due to excessive hydrogen pressure in the system during operation.

[0034] The above are only preferred embodiments of the present invention. The protection scope of the present invention is not limited to the above embodiments. All technical solutions under the concept of the present invention belong to the protection scope of the present invention. It should be pointed out that for ordinary technicians in this technical field, some improvements and modifications without departing from the principle of the present invention should also be regarded as the protection scope of the present invention.

Claims

1. A microchannel solid-state hydrogen storage thermal management system, characterized in that: The invention comprises a pressure controller (1), a safety valve (2), a circulation pump (3), a ball valve (4), a microchannel reactor (5), a three-way ball valve (6), and a cooler (7); the safety valve (2), the circulation pump (3), the ball valve (4), the microchannel reactor (5), the three-way ball valve (6), and the cooler (7) are connected in sequence through pipelines to form a loop; a hydrogen outlet (51) of the pressure controller (1) is connected to the pipelines between the safety valve (2) and the cooler (7); a hydrogen inlet (59) of the pressure controller (1) is connected to a hydrogen source; and one port of the three-way ball valve (6) is a hydrogen outlet (51).

2. A microchannel solid-state hydrogen storage thermal management system according to claim 1, characterized in that: The microchannel reactor (5) is provided with a closed container consisting of a stainless steel tank body (510) on which a stainless steel flange cover (56) is installed, a sealing gasket (54) is arranged between the stainless steel flange cover (56) and the stainless steel tank body (510), and the stainless steel tank body (510) and the stainless steel flange cover (56) are sealed by the sealing gasket (54) and the fastening bolts (55); a hydrogen outlet (51) and a temperature sensor (53) are welded on the stainless steel flange cover (56), the hydrogen outlet (51) is connected to a pressure sensor (52) via a three-way joint, and the lower end of the temperature sensor (53) extends into the hydrogen storage material reaction bed in the stainless steel tank body (510).

3. A microchannel solid-state hydrogen storage thermal management system according to claim 2, characterized in that: The stainless steel tank body (510) is provided with a heating layer (58) on the periphery thereof, which enables the interior of the reactor to reach an initial reaction temperature state before the hydrogen absorption reaction and provides a reaction heat source during the hydrogen release reaction. The heating layer (58) is wrapped with a heat-insulating layer (57).

4. A microchannel solid-state hydrogen storage thermal management system according to claim 2, characterized in that: The hydrogen inlet (59) is welded to the lower part of the stainless steel tank body (510) of the microchannel reactor (5), one end of which extends into the interior of the stainless steel tank body (510) and is connected to the stainless steel tank body (510), and the other end of which extends to the outside of the insulation layer (57), so that hydrogen can fully flow through the interior of the reactor through bottom air intake and top air outlet.

5. A microchannel solid-state hydrogen storage thermal management system according to claim 2, characterized in that: The reaction bed in the microchannel reactor (5) is a hydrogen storage material powder compact (511), which is stacked in the microchannel reactor (5) via a stainless steel support (512). Gaps are left between the hydrogen storage material powder compact (511) and the inner wall of the stainless steel tank (510) of the microchannel reactor (5), as well as between the hydrogen storage material powder compacts (511), thereby providing abundant channels for hydrogen flow and mass transfer.

6. A microchannel solid-state hydrogen storage thermal management system according to claim 5, characterized in that: The hydrogen storage material powder compact (511) is made of AB5 type or Mg-based hydrogen storage alloy powder compact.

7. A microchannel solid-state hydrogen storage thermal management system according to any one of claims 1 to 6, characterized in that: Hydrogen gas with a pressure higher than that of the hydrogen absorption reaction enters the system through a pressure controller (1). The pressure controller (1) controls the flow rate of hydrogen gas according to a preset hydrogen absorption pressure, and maintains the hydrogen gas in the system at the set pressure value through dynamic feedback regulation. When the ball valve (4) is open, the hydrogen gas entering the system enters the microchannel reactor (5) through a circulation pump (3). The microchannel reactor (5) provides an initial temperature condition for the hydrogen absorption reaction through an outer heating layer (58), and the microchannel reactor (5) starts the hydrogen absorption reaction process. Due to the heat release of the hydrogen absorption reaction, the hydrogen gas in the microchannel reactor (5) is heated to a temperature of 100 °C. The heat is absorbed and the temperature rises; when the three-way ball valve (6) (4) connects the reactor and the cooler (7), the high-temperature hydrogen flows out of the microchannel reactor (5) to the cooler (7) for cooling, and the reaction heat brought out by the hydrogen from the microchannel reactor (5) is discharged from the system; since the hydrogen is consumed by the hydrogen absorption reaction in the microchannel reactor (5), the hydrogen pressure decreases after flowing out of the microchannel reactor (5) and the cooler (7), and at this time, the pressure controller (1) connected to the system adjusts the hydrogen flow rate to restore the hydrogen pressure in the system to a preset value, and the hydrogen enters the next cycle under the action of the circulation pump (3).

8. A microchannel solid-state hydrogen storage thermal management system according to claim 7, characterized in that: After the hydrogen storage reaction is completed, the ball valve (4) and the three-way ball valve (6) (4) are closed to achieve hydrogen storage in the microchannel reactor (5) in a stable and sealed state; during the hydrogen release reaction process, the microchannel reactor (5) provides a reaction heat source through the peripheral heating layer (58), and when the hydrogen release reaction temperature is reached in the microchannel reactor (5), the three-way ball valve (6) (4) is connected to the microchannel reactor (5) and the hydrogen outlet (51), thereby starting the hydrogen release reaction process.

9. A microchannel solid-state hydrogen storage thermal management system according to claim 7, characterized in that: When the hydrogen pressure in the gas circuit is higher than the set pressure value of the safety valve (2), the safety valve (2) is in an open state and discharges hydrogen to the outside of the system.

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