Preparation process and preparation device for compacted magnesium hydride block based on magnesium having multiple interstitial spaces

Abstract

The present invention relates to the technical field of the preparation of magnesium hydride, and particularly relates to a preparation process for a compacted magnesium hydride block based on magnesium having multiple interstitial spaces. The preparation process comprises: subjecting a strip-shaped magnesium sheet to compression molding in a regular cavity to obtain a compacted magnesium block, wherein interstitial spaces used for storing heat are formed inside the compacted magnesium block; and heating the compacted magnesium block in a sealed reaction space with a pressure higher than normal pressure, introducing hydrogen and bringing same into contact with the compacted magnesium block, and bonding the compacted magnesium block and the hydrogen within a set period of time to obtain a compacted magnesium hydride block. Further disclosed is a preparation device for a compacted magnesium hydride block, which device comprises a reaction kettle, a heating frame, a temperature detection device, a pressure detection device, a control module, a heat exchange system and a gas pipeline system. In the present application, by using the compacted magnesium block and the preparation device for a compacted magnesium hydride block in combination, the problem of high power consumption during traditional magnesium hydride preparation is solved, no alloy needs to be added to magnesium to promote a reaction, energy can be effectively utilized, heat energy loss can be reduced, and stable control can be achieved.

Description

A process and device for preparing solid magnesium hydride based on multi-interstitial magnesium Technical Field

[0001] The present invention relates to the technical field of magnesium hydride preparation, and in particular to a process and a device for preparing solid block magnesium hydride based on multi-interstitial magnesium. Background Art

[0002] One method of storing hydrogen is through the use of metal hydrides, namely magnesium hydride (MgH2). Metal hydrides are not only easy to use and safe, as they do not require the specialized conditions of ultra-high pressure and extremely low temperature to store hydrogen, but also offer a high hydrogen storage capacity per unit volume.

[0003] There are two traditional methods for preparing magnesium hydride. One is to grind magnesium into a powder and combine the powdered magnesium with high-temperature, high-pressure hydrogen in a high-pressure device. During the process, the reaction pressure generally needs to be maintained at 6-8 MPa, the reaction temperature needs to be controlled above 650°C, and the temperature in the entire reactor needs to be stable above the reaction temperature. The high-temperature and high-pressure reaction conditions result in high energy consumption, and the binding rate decreases as the reaction proceeds. The preparation purity can reach 95%-98%. The other method combines magnesium and hydrogen during the condensation process of vaporized magnesium. This method has higher energy consumption, but the purity can reach 98%-99%. At present, in order to optimize the reaction, this method will mix some alloys into the magnesium to increase its utilization rate of thermal energy. However, the intervention of other alloys will complicate the process. Therefore, in response to the problems existing in the prior art, the present invention has developed a solid block magnesium hydride preparation process and preparation device based on multi-interstitial magnesium. Summary of the Invention

[0004] The present invention aims to provide a process and apparatus for preparing solid magnesium hydride based on multi-interstitial magnesium, so as to solve the problems in the prior art of preparing magnesium hydride using powdered magnesium or vaporized magnesium, such as excessive energy consumption and the need to add other alloys to promote the reaction, which affects the process and cost.

[0005] The technical solution of the present invention is: a process for preparing solid block magnesium hydride based on multi-interstitial magnesium, comprising:

[0006] The strip-shaped magnesium sheet is pressed into a regular cavity to obtain a solid magnesium block, wherein the solid magnesium block has a gap space for storing heat;

[0007] The solid magnesium block is heated in a sealed reaction space at a pressure higher than normal, and hydrogen is introduced into contact with the solid magnesium block. During the process, the temperature and pressure change trends in the reaction space are detected, and the temperature and pressure are adjusted according to the change trends;

[0008] Solid magnesium hydride is obtained by combining solid magnesium with hydrogen within a set time.

[0009] Preferably, in the reaction space, the operating temperature is not lower than 340° C., and the operating pressure is not lower than 0.6 MPa.

[0010] Preferably, the thickness of the strip-shaped magnesium sheet is less than 200 μm.

[0011] Preferably, the density of the solid magnesium block is 70% to 80% of the density of solid magnesium.

[0012] Preferably, the solid magnesium block is placed on a heating rack in the reaction space, and there is a linear contact between the solid magnesium block and the heating rack, so that the heat of the heating rack is transferred upward to the solid magnesium block.

[0013] Preferably, the hydrogen flows in the reaction space based on the pressure difference or temperature difference, and is in full contact with the solid magnesium block in the flowing state.

[0014] A device for preparing solid magnesium hydride, comprising:

[0015] A reactor, wherein the reaction space is formed in the reactor and the reactor has at least two gas ports, wherein the two gas ports are located at the top and the bottom of the reactor respectively;

[0016] A heating rack, the heating rack comprising a fixed base and a heating rod mounted on the fixed base; each layer of the heating rack has at least two heating rods, each heating rod having a heating wire disposed therein, the heating rod being used to support the solid magnesium block and transfer heat;

[0017] A temperature detection device and a pressure detection device, installed on the reactor, for detecting the temperature and pressure inside the reactor respectively;

[0018] a control module, adjusting the temperature and pressure in the reactor based on detection data of the temperature detection device and the pressure detection device;

[0019] and a gas pipeline system to achieve the circulation of gas in the reactor.

[0020] Preferably, the reactor is provided with a fan device for causing the hydrogen to flow based on the pressure difference;

[0021] Alternatively, a high-temperature device for causing hydrogen to flow based on a temperature difference is provided at the bottom of the reactor, and the high-temperature device is independent of the space inside the reactor.

[0022] Preferably, the gas pipeline system includes a high-temperature resistant pipe body, a high-temperature and high-pressure resistant valve body, an oxygen content sensor, a hydrogen flow sensor, and also includes a pressure relief device and a vacuum device connected to the reactor;

[0023] The high temperature resistant tube body is connected to the gas ports at the top and bottom of the reactor. The high temperature and high pressure valve body, oxygen content sensor and hydrogen flow sensor are all installed on the high temperature resistant tube body to monitor the hydrogen flow and oxygen flow at the gas port.

[0024] Preferably, a heat exchange system is further included, and the heat exchange system uses a cooling coil; the cooling coil is installed in the reaction space, or in the partition space at the bottom of the reactor.

[0025] Compared with the prior art, the advantages of the present invention are:

[0026] (1) The present invention uses solid block magnesium formed by pressing strip magnesium sheets to prepare solid block magnesium hydride. Based on the structure of the solid block magnesium, the continuity of temperature transfer is guaranteed under heating conditions. At the same time, the internal gap space is conducive to the storage of heat and is not easy to lose. The solid block magnesium formed by the structure is granular and can be conveniently placed on a heating rack for heating, and heat can be directly transferred to the solid block magnesium.

[0027] (2) Solid magnesium is used in conjunction with a solid magnesium hydride preparation device to achieve a relatively low-temperature and low-pressure reaction, reducing the problem of high power consumption required for traditional magnesium hydride manufacturing. There is no need to add any alloy to the magnesium to promote the reaction, which can effectively utilize energy, reduce heat loss, and control stability. On the other hand, due to the decrease in temperature during the reaction of solid magnesium hydride, the overall temperature is controlled below the ignition point of hydrogen, thereby improving the safety of hydrogen use and the safety of solid magnesium hydride production.

[0028] (3) Since the solid magnesium block and the heating rack have a certain amount of line contact, and the heating rack is located below the solid magnesium block, heat can be directly transferred upward to the solid magnesium block. There is no need to ensure that the temperature in the entire reactor is stable. It is only necessary to ensure that the temperature of the heating rack itself can reach the specified height. The heat can effectively make the solid magnesium block reach the reaction temperature, further making the control of the preparation device easier and avoiding the problem of uneven heating of the solid magnesium block. At the same time, the line contact between the solid magnesium block and the heating rack can not only meet the heat transfer requirements, but also avoid the disadvantage of the solid magnesium block not being able to fully contact with hydrogen due to surface contact.

[0029] (4) Compared with the traditional preparation method, the present application can also prepare the purity of magnesium hydride to more than 99.8% under the condition of low pressure and temperature. Therefore, for the preparation of solid block magnesium hydride with lower purity requirements, the temperature and pressure required for preparation are lower, and thus the applicability of the present application in the preparation of solid block magnesium hydride with low purity requirements is higher.

[0030] (5) The solid block magnesium hydride preparation device of the present application can also be used to prepare hydrogen in reverse, and by adjusting the changes in the environmental conditions in the reaction space, a dual-purpose effect is achieved; the solid block magnesium hydride is placed in a reactor, and the release of hydrogen is achieved by controlling the temperature in the reaction space under normal pressure or negative pressure. During the process, based on the structure of the solid block magnesium hydride, the continuity of heat and good internal heat storage performance can also be guaranteed. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The present invention will be further described below with reference to the accompanying drawings and embodiments:

[0032] FIG1 is a schematic structural diagram of a device for preparing solid magnesium hydride according to the present invention;

[0033] FIG2 is a schematic structural diagram of a solid magnesium block placed on a heating rack in one embodiment of the present invention;

[0034] FIG3 is a schematic structural diagram of a solid magnesium block placed on a heating rack in another embodiment of the present invention;

[0035] Including: 1. Solid magnesium block; 2. Heating rack, 21. Fixing seat, 22. Heating rod; 3. Reactor, 31. Reaction space, 32. Air port, 33. Partition space, 34. Opening and closing device, 35. Observation port; 4. Heat exchange system, 4a. Cooling coil, 41. Water inlet pipe, 42. Water outlet pipe; 5. Fan device; 6. High-temperature device. DETAILED DESCRIPTION

[0036] The present invention is further described in detail below with reference to specific embodiments:

[0037] For ease of understanding, it should be noted that the primary problem addressed by the present application is the preparation of solid magnesium hydride by combining solid magnesium with hydrogen for hydrogen energy storage. In the prior art, in the process of preparing magnesium hydride using powdered magnesium or vaporized magnesium, the reaction pressure and reaction temperature are too high, which leads to excessive energy consumption. Furthermore, the latter requires the addition of other alloys to promote the reaction, which affects the process and cost. Therefore, in order to solve the above problems, the present application has developed a process and apparatus for preparing solid magnesium hydride.

[0038] Example 1

[0039] A process for preparing solid magnesium hydride based on multi-interstitial magnesium comprises:

[0040] (1) A magnesium sheet with a thickness of 300 μm and cut into strips is pressed into a mold with a regular cavity to obtain a solid magnesium block (i.e., multi-gap magnesium). The solid magnesium block is in the form of large particles and can be constructed into a columnar or other shapes.

[0041] Solid magnesium blocks contain interstitial spaces, a microscopic structure that facilitates heat storage and prevents heat loss during subsequent heating. This provides better temperature stability than traditional magnesium powder blocks, resulting in higher thermal energy utilization and lower energy consumption. This interstitial space also allows the density of the pressed solid magnesium blocks to be controlled to 70% to 80% of that of solid magnesium. From a microscopic perspective, solid magnesium blocks differ from powders or blocks formed by pressing powders. When disassembled, they form continuous strips, allowing for continuous temperature transfer. Furthermore, after being pressed, the solid magnesium blocks facilitate placement during subsequent heating.

[0042] (2) The solid magnesium block is placed on a heating rack in a reaction space, and the solid magnesium block is heated in a sealed reaction space. The initial pressure in the reaction space is set to 1 MPa, and the initial temperature is set to 360°C. Hydrogen is introduced to contact the solid magnesium block, and solid magnesium hydride is obtained by combining the solid magnesium block and the hydrogen within a set time.

[0043] (3) During the reaction of solid magnesium and hydrogen, the temperature and pressure change trends in the reaction space are detected, and the temperature and pressure are adjusted according to the change trends; in the initial state, the amount of hydrogen entering the reactor is determined by a hydrogen flow sensor. The hydrogen flow rate is correlated with the reaction speed of the solid magnesium. By constructing a flow curve of the amount of hydrogen entering and the reaction time, it is determined whether the reaction meets expectations, and the environment in the reactor is adjusted by lowering the temperature and pressure or increasing the temperature and pressure; to a certain extent, energy consumption is reduced and the precise control of energy consumption is increased. By constructing a flow curve of the initial theoretical reaction of hydrogen and solid magnesium, the flow curve of the initial theoretical reaction is used for fitting in the subsequent reaction process, and the reaction parameters (including reaction temperature, pressure, duration, etc.) are adjusted to enable the solid magnesium to react with hydrogen under the optimal working environment.

[0044] Example 2

[0045] A process for preparing solid magnesium hydride based on multi-interstitial magnesium comprises:

[0046] (1) A magnesium sheet with a thickness of 200 μm and cut into strips is pressed into a mold with a regular cavity to obtain a solid magnesium block (i.e., multi-gap magnesium). The solid magnesium block is in the form of large particles and can be constructed into a columnar or other shapes.

[0047] (2) The solid magnesium block is placed on a heating rack in a reaction space, and the solid magnesium block is heated in a sealed reaction space. The initial pressure in the reaction space is set to 1 MPa, and the initial temperature is set to 360°C. Hydrogen is introduced to contact the solid magnesium block, and solid magnesium hydride is obtained by combining the solid magnesium block and the hydrogen within a set time.

[0048] (3) Constructing the flow curve of the initial theoretical reaction. In the subsequent reaction process, the flow curve of the initial theoretical reaction is used for fitting and the reaction parameters (including reaction temperature, pressure, duration, etc.) are adjusted so that the solid magnesium can react with hydrogen under the optimal working environment.

[0049] Example 3

[0050] The difference between this embodiment and embodiment 1 is that in step (1), a strip-shaped magnesium sheet with a thickness of 150 μm and formed by cutting is pressed into a mold with a regular cavity to obtain a solid magnesium block; other reaction conditions are the same as those in embodiment 1.

[0051] Example 4

[0052] The difference between this embodiment and embodiment 1 is that in step (1), a strip-shaped magnesium sheet with a thickness of 100 μm and formed by cutting is pressed into a mold with a regular cavity to obtain a solid magnesium block; other reaction conditions are the same as those in embodiment 1.

[0053] Table 1: Hydrogenation rate data table of the reactions in Examples 1 to 4;

[0054] As shown in Table 1, under the initial set temperature and pressure, the smaller the thickness of the magnesium strip, the higher the hydrogenation rate. This is mainly because when the magnesium strip is too thick, the internal gap space will increase after being pressed into shape, which will accelerate heat loss. At the same time, the specific surface area will decrease, the contact surface for chemical reaction will also be less, and the reaction rate will be lower. Therefore, controlling the thickness of the magnesium strip below 200μm can ensure the performance of the solid magnesium during the heating process.

[0055] Example 5

[0056] A process for preparing solid magnesium hydride based on multi-interstitial magnesium comprises:

[0057] (1) A magnesium sheet with a thickness of 100 μm and formed by cutting is pressed into a mold with a regular cavity to obtain a solid block of magnesium (i.e., multi-gap magnesium). The solid block of magnesium is in the form of large particles and can be constructed into a columnar or other shapes.

[0058] (2) The solid magnesium is placed on a heating rack in a reaction space, and the solid magnesium is heated in a sealed reaction space. The initial pressure in the reaction space is set to 1 MPa, and the initial temperature is set to 400°C. Hydrogen is introduced to contact the solid magnesium, and solid magnesium hydride is obtained by combining the solid magnesium and hydrogen within a set time.

[0059] (3) Constructing the flow curve of the initial theoretical reaction. In the subsequent reaction process, the flow curve of the initial theoretical reaction is used for fitting and the reaction parameters (including reaction temperature, pressure, duration, etc.) are adjusted so that the solid magnesium can react with hydrogen under the optimal working environment.

[0060] Example 6

[0061] The difference between this embodiment and embodiment 5 is that in step (2): the solid magnesium block is placed on a heating rack in the reaction space, the solid magnesium block is heated in the sealed reaction space, the initial pressure in the reaction space is set to 0.6 MPa, the initial temperature is set to 400°C, and hydrogen is introduced to contact the solid magnesium block, and solid magnesium hydride is obtained by combining the solid magnesium block and the hydrogen within a set time.

[0062] Table 2: Hydrogenation rate data table of the reactions in Examples 5 and 6;

[0063] Table 2 shows that the hydrogenation rate gradually increases with increasing pressure within the reaction space. In actual applications, it has been found that the minimum required pressure for solid magnesium is 0.6 MPa. Increasing the pressure above this minimum requirement can significantly improve purity and reduce reaction time and energy consumption to a certain extent. However, higher pressures also increase hydrogen safety risks and the cost of the production equipment. Therefore, the ideal operating pressure is set between 0.8 and 1 MPa.

[0064] Combining Table 1 and Table 2, it can be seen that in Example 4 and Example 5, when other conditions remain unchanged, the higher the temperature in the reaction space, the higher the hydrogenation rate. In actual application, it was found that the minimum required temperature for the solid magnesium block is 340°C. Increasing the temperature can increase the activity of magnesium and hydrogen and reduce the reaction time. However, correspondingly, higher temperatures will also lead to higher energy consumption and are closer to the ignition point of hydrogen, increasing safety hazards. In order to eliminate the interference of the instability of the heating device and ensure the continuity of the reaction, the ideal temperature should be 350-450°C, which can ensure the normal reaction while reducing energy waste.

[0065] Therefore, based on the structure of the solid magnesium block and placing it directly on a heating rack in the reaction space to react with hydrogen, while ensuring the purity of the preparation, only the working pressure needs to reach 0.8-1MPa and the working temperature needs to reach 350-450°C to ensure that the purity of the final prepared solid magnesium hydride can reach more than 99.8%, meeting the characteristics of low energy consumption and high performance. Compared with the traditional process of preparing magnesium hydride from powdered magnesium and vaporized magnesium, this application has significant advantages in working temperature and working pressure.

[0066] In summary, in the present application, the reaction between solid magnesium and hydrogen at relatively low temperature and low pressure can be achieved without the need for alloy combination, thereby reducing the problem of high power consumption required for traditional magnesium hydride manufacturing, and without adding any alloy to the solid magnesium to promote the reaction, which can effectively utilize energy, reduce heat loss, and ensure stable control. On the other hand, since the temperature of the solid magnesium hydride is reduced during the reaction, the overall temperature is controlled below the ignition point of hydrogen, thereby improving the safety of hydrogen use and the safety of solid magnesium hydride production.

[0067] Based on the above-mentioned solid block magnesium hydride preparation process, it can be known that the heating of the solid block magnesium must rely on the preparation device. Therefore, the present invention also develops a solid block magnesium hydride preparation device, as shown in Figure 1, including a reactor 3, a heating frame 2, a heat exchange system 4, a gas pipeline system, a temperature detection device, a pressure detection device and a control module.

[0068] A reaction space 31 is formed in the reactor 3 and has at least two gas inlets 32, which are located at the top and bottom of the reactor 3 respectively. The reactor 3 is made of 316L stainless steel, and can also be made of other high-temperature and high-pressure resistant materials suitable for hydrogen. It is provided with an opening and closing device 34 and an observation port 35. The opening and closing device 34 facilitates easy removal of the solid magnesium block 1 therein, and the observation port 35 is used to observe the working status in the reaction space 31, so that the operator can make timely manual adjustments.

[0069] Multiple heating racks 2 are installed in the reaction space 31 and stacked in multiple layers. As shown in Figure 2, the heating racks 2 include a fixed base 21 and a heating rod 22 installed on the fixed base 21. Each layer of the heating racks 2 has at least two heating rods 22. The heating rods 22 are equipped with temperature-controlled heating wires, and the on / off time and power can be set. The temperature control range is set to ±15°C. Two heating rods 22 form a group, which can be used to support the solid magnesium block 1, so that there is a linear contact between the heating rods 22 and the solid magnesium block 1. The heating rods 22 must have sufficient strength to prevent deformation. When the heating rods 22 are supported below the solid magnesium block, the temperature is transferred upward.

[0070] In one embodiment, as shown in FIG2 , two heating rods 22 are combined to form a U-shaped structure, with the ends fixedly connected to the fixing seat 21 , so as to ensure that there is a linear contact between the solid magnesium block 1 and the heating rods 22 , and the heat of the heating rack 2 is transferred upward to the solid magnesium block 1 .

[0071] In other embodiments, as shown in FIG. 3 , two heating rods 22 are installed in parallel, with both ends fixedly connected to the fixing base 21 . Two adjacent heating rods 22 form a group and are used to place the solid magnesium block 1 .

[0072] It should be noted that when the solid magnesium block 1 is supported on the heating frame 2, surface contact cannot be adopted, otherwise the contact surface of the solid magnesium block 1 cannot fully contact with the hydrogen to react; therefore, by setting the heating rod 22, it can be ensured that there is a line contact fit between the heating rod 22 and the solid magnesium block 1.

[0073] In the present invention, since the heating rack 2 is closely aligned with the solid magnesium block 1, the heating rack 2 does not need to maintain a stable temperature throughout the reactor 3. As long as the heating rack 2 itself reaches a specified temperature, its heat can be effectively transferred to the solid magnesium block 1, allowing the entire solid magnesium block 1 to reach the reaction temperature. Furthermore, the preparation apparatus of the present application is easier to control, and there is no need to consider the problem of uneven heating of the solid magnesium block 1.

[0074] The heat exchange system 4 is used to cool the reactor 3. Its purpose is to provide a safety measure for the reactor 3, preventing safety issues caused by hypothermia. However, it does not affect the operation of the reactor itself and is optional in practical applications. In one embodiment, the heat exchange system 4 can be composed of a cooling coil 4a installed in the reaction space 31. The cooling coil 4a is connected to the water inlet pipe 41 and the water outlet pipe 42 installed at the bottom of the reactor 3. In other embodiments, a partition space 33 can be formed below the reactor 3, and the water cooling coil 4a can be installed in the partition space 33.

[0075] The gas pipeline system includes a high-temperature resistant pipe body, a high-temperature resistant and high-pressure valve body, an oxygen content sensor, a hydrogen flow sensor, and also includes a pressure relief device and a vacuum pumping device connected to the reactor 3. The high-temperature resistant pipe body is connected to the gas ports 32 at the top and bottom of the reactor 3. The high-temperature resistant and high-pressure valve body, the oxygen content sensor, and the hydrogen flow sensor are all installed on the high-temperature resistant pipe body to monitor the hydrogen flow and oxygen flow at the gas port 32. The pressure relief device can be a burst valve installed on the top of the reactor 3 to prevent the gas pressure in the reactor 3 from being too high. Since the reactor 3 is used for the reaction between solid and gas, and the quality of hydrogen is relatively low, the gas can be better stratified in the early stage by static means, and other impurity gases can be discharged from the gas port 32 at the bottom. The vacuum pumping device is used in conjunction with the vacuum pumping means to ensure the safety of hydrogen use to the greatest extent.

[0076] The temperature detection device and the pressure detection device are used to detect the temperature and pressure in the reactor 3 respectively. The temperature detection device can adopt a temperature sensor. By setting temperature measuring points at different positions of the reaction space 31, generally setting no less than four temperature measuring points, and then the temperature sensors are installed at different temperature measuring points; the pressure detection device can adopt a pressure sensor. One pressure sensor can be set and installed at a position away from the air port 32; the data of the temperature sensor and the pressure sensor can be fed back to the control module, and then the control module adjusts the temperature and pressure in the reactor 3 based on the detection data of the temperature sensor and the pressure sensor. The temperature in the reactor 3 is respectively increased and decreased by the heating rack 2 and the heat exchange system 4.

[0077] In order to ensure that the hydrogen can fully contact the solid magnesium block 1, in one embodiment, a fan device 5 is provided in the reactor 3 to make the hydrogen flow based on the pressure difference; the fan device 5 is installed on one side of the reaction space 31. By turning on the fan device 5, the hydrogen flows in the reaction space 31, thereby accelerating the contact with the solid magnesium block 1.

[0078] In other embodiments, a high-temperature device 6 is installed at the bottom of the reactor 3 to cause hydrogen to flow due to temperature differences. By rapidly heating the gas at the bottom of the reactor 3, the gas at the bottom diffuses due to the temperature difference, forming convection, allowing the hydrogen to flow. It is important to note that the high-temperature device 6 must be isolated from the space within the reactor 3 to prevent the high temperature from affecting the hydrogen and reduce safety risks. In one embodiment, the high-temperature device 6 can be installed within the partition space 33.

[0079] Due to the structural characteristics of solid magnesium and the solid magnesium hydride preparation device, reactions can be carried out under relatively low temperature and low pressure conditions, while also ensuring higher purity of the solid magnesium hydride. Therefore, when the application scenario requires the preparation of solid magnesium hydride with lower purity requirements, the required temperature and pressure are lower, which in turn makes the solid magnesium hydride preparation device more applicable.

[0080] As a further optimization, the solid block magnesium hydride preparation device of the present application can also be used to prepare hydrogen in reverse and be constructed as a hydrogen generation device; the specific working principle is to place the solid block magnesium hydride on a heating rack, and the temperature is controlled at above 280°C. Under normal pressure or negative pressure, the solid block magnesium hydride will decompose into hydrogen and a solid block magnesium composed of continuous strip magnesium sheets. By heating the heating wire to 300°C, the solid block magnesium hydride can stably release hydrogen, and its heat can be effectively utilized due to the continuity of the structure, and the gap space inside it can also store heat energy well. During the process, the two gas ports at the top and bottom of the reactor are used for exhaust in the initial stage, and hydrogen is discharged from the top gas port, which is equivalent to a means of purifying hydrogen.

[0081] Since hydrogen is discharged from the top gas port and the temperature inside the reactor is above 300°C, a cooling spiral metal sheet is configured at the top gas port to achieve temperature control and reduce the hydrogen temperature to prevent burns or hydrogen self-ignition.

[0082] In summary, the solid block magnesium hydride preparation device of the present application achieves the purpose of dual purpose. It can not only stably prepare solid block magnesium hydride, but also stably release hydrogen from the solid block magnesium hydride. In application scenarios, hydrogen can be collected in areas with a large amount of waste hydrogen and safely transported to areas with high hydrogen demand at low pressure, and then released. The heating rack can also be taken out and transported separately together with the solid block magnesium hydride, which can reduce the transportation cost of hydrogen to a certain extent and improve the convenience of hydrogen use.

[0083] The above embodiments are only for illustrating the technical concept and features of the present invention, and their purpose is to enable people familiar with this technology to understand the content of the present invention and implement it accordingly, and they are not intended to limit the scope of protection of the present invention. For those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments, and the present invention can be implemented in other specific forms without departing from the spirit or basic characteristics of the present invention. Therefore, no matter from which point of view, the embodiments should be regarded as exemplary and non-restrictive. The scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes that fall within the meaning and scope of the equivalent elements of the claims are included in the present invention.

Claims

1. A process for preparing solid block magnesium hydride based on multi-interstitial magnesium, characterized in that: include: The strip-shaped magnesium sheet is pressed into a regular cavity to obtain a solid magnesium block, wherein the solid magnesium block has a gap space for storing heat; The solid magnesium block is heated in a sealed reaction space at a pressure higher than normal, and hydrogen is introduced into contact with the solid magnesium block. During the process, the temperature and pressure change trends in the reaction space are detected, and the temperature and pressure are adjusted according to the change trends; Solid magnesium hydride is obtained by combining solid magnesium with hydrogen within a set time.

2. The process for preparing solid block magnesium hydride based on multi-interstitial magnesium according to claim 1, characterized in that: In the reaction space, the operating temperature is not lower than 340° C., and the operating pressure is not lower than 0.6 MPa.

3. The process for preparing solid block magnesium hydride based on multi-interstitial magnesium according to claim 1, characterized in that: The thickness of the strip-shaped magnesium sheet is less than 200 μm.

4. The process for preparing solid magnesium hydride based on multi-interstitial magnesium according to claim 3, characterized in that: The density of the solid magnesium block is 70% to 80% of the density of solid magnesium.

5. The process for preparing solid block magnesium hydride based on multi-interstitial magnesium according to claim 1, characterized in that: The solid magnesium block is placed on a heating rack in the reaction space. There is a line contact between the solid magnesium block and the heating rack, and the heat of the heating rack is transferred upward to the solid magnesium block.

6. The process for preparing solid magnesium hydride based on multi-interstitial magnesium according to claim 1, characterized in that: The hydrogen flows in the reaction space based on the pressure difference or temperature difference and is in full contact with the solid magnesium block in the flowing state.

7. A solid block magnesium hydride preparation device according to any one of claims 1 to 6, characterized in that: include: A reactor, wherein the reaction space is formed in the reactor and the reactor has at least two gas ports, wherein the two gas ports are located at the top and the bottom of the reactor respectively; A heating rack, the heating rack comprising a fixed base and a heating rod mounted on the fixed base; each layer of the heating rack has at least two heating rods, each heating rod having a heating wire disposed therein, the heating rod being used to support the solid magnesium block and transfer heat; A gas pipeline system to realize the circulation of gas in the reactor; A temperature detection device and a pressure detection device, installed on the reactor, for detecting the temperature and pressure inside the reactor respectively; The control module adjusts the temperature and pressure in the reactor based on the detection data of the temperature detection device and the pressure detection device.

8. The device for preparing solid magnesium hydride according to claim 7, characterized in that: The reactor is provided with a fan device for causing hydrogen to flow based on a pressure difference; Alternatively, a high-temperature device for causing hydrogen to flow based on a temperature difference is provided at the bottom of the reactor, and the high-temperature device is independent of the space inside the reactor.

9. The device for preparing solid magnesium hydride according to claim 7, characterized in that: The gas pipeline system includes a high-temperature resistant pipe body, a high-temperature and high-pressure resistant valve body, an oxygen content sensor, a hydrogen flow sensor, and also includes a pressure relief device and a vacuum device connected to the reactor; The high temperature resistant tube body is connected to the gas ports at the top and bottom of the reactor. The high temperature and high pressure valve body, oxygen content sensor and hydrogen flow sensor are all installed on the high temperature resistant tube body to monitor the hydrogen flow and oxygen flow at the gas port.

10. The device for preparing solid magnesium hydride according to claim 7, characterized in that: It also includes a heat exchange system, which uses a cooling coil; the cooling coil is installed in the reaction space, or in the partition space at the bottom of the reactor.

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