Glass capillary array for gas storage and preparation method thereof

Abstract

The present invention provides a glass capillary array for gas storage and a preparation method thereof, comprising the following steps: selecting a pressure-resistant glass material to prepare a glass tube with smooth inner and outer surfaces, and drawing and cutting it into a glass single tube; arranging and bundling the glass single tubes, and then drawing and cutting them under a vacuum state to obtain a plurality of glass multi-tube arrays; arranging the glass multi-tube arrays into a screen arrangement mold row by row to form a closely arranged screen segment; placing the arranged screen segment into a vacuum melting and pressing system, and pressurizing it under a preset temperature and vacuum environment, so that all the multi-tubes in the screen segment are melted and pressed into one; hanging and fixing the melted and pressed screen segment, and slowly placing one end into the effective temperature zone of a wire drawing furnace, and heat-insulating the screen segment within the required temperature, so that one end of the screen segment is melted into one, and the multi-tube structure is sealed; slowly cooling the screen segment to anneal it, and obtain the required glass capillary array. The method of the present invention effectively improves the overall pressure resistance of the glass capillary and eliminates the environmental restrictions brought by other sealed materials.

Description

Technical Field

[0001] The present invention relates to the technical field of energy gas storage, and in particular to a glass capillary array for gas storage and a preparation method thereof. Background Art

[0002] With the country's vigorous promotion of hydrogen energy development, the storage and transportation of hydrogen has become a research hotspot, among which high-pressure gaseous hydrogen storage is the most mature and widely used. Glass capillaries have many advantages such as high pressure resistance, high storage, light weight, and easy splicing into large arrays. In addition, glass is a good hydrogen barrier that can safely hold hydrogen for several years without hydrogen embrittlement. Glass fiber tubes with a diameter of only a few microns have a high pressure resistance of more than 150MPa, far exceeding the current 70MPa of hydrogen storage tanks, and are 3 times lighter than steel. Bundling to a larger structure makes the gas tank variable in size, providing a safer method for the storage and transportation of hydrogen. The advantage of the capillary array system is that many individual capillaries can be bundled, each capillary acting as a single pressure vessel. Since the absolute amount of hydrogen in each capillary is too small, an explosive atmosphere will not be formed.

[0003] Glass capillaries usually use materials such as indium tin alloy to close one end of a single glass microtube, and then use fusible materials such as epoxy rubber to fill it, and then splice a large number of glass microtubes. However, this method has the following shortcomings: two components other than glass are introduced into the capillary array, epoxy resin is prone to failure in extreme environments, and the low melting point of indium tin alloy also restricts the use environment of the capillary.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent document 1: Chinese patent with publication number CN111336399A. Summary of the invention

[0007] The purpose of the present invention is to provide a glass capillary array for gas storage and a preparation method thereof in view of the deficiencies in the prior art, combining a screening method and a hot melt method to achieve internal fusion and end face sealing of the capillary array. The overall structure is designed as an integrated structure. The obtained glass capillary array has only one medium, namely glass material, which can effectively improve the overall pressure resistance of the glass capillary, eliminate the environmental restrictions brought by other sealing materials, and improve the environmental adaptability.

[0008] According to a first aspect of the present invention, a method for preparing a glass capillary array for gas storage is provided, comprising the following steps:

[0009] Step 1, selecting a pressure-resistant glass material to prepare a glass tube with smooth inner and outer surfaces, drawing the glass tube in a drawing furnace and cutting it into a single glass tube;

[0010] Step 2, arranging and bundling a plurality of glass single tubes and placing them in a drawing furnace, drawing them under vacuum, and cutting them into required lengths to obtain a plurality of glass multi-tube arrays; wherein the smallest unit of the glass multi-tube array is a glass capillary;

[0011] Step 3: Arrange the glass multi-tube arrays row by row into the screen arrangement mold, and tighten the mold after the arrangement is completed to form closely arranged screen segments;

[0012] Step 4: Place the arranged screen segments into a vacuum melting and pressing system, and pressurize them under a preset temperature and vacuum environment so that all the multiple tubes in the screen segments are melted and pressed into one;

[0013] Step 5, hang and fix the melted and pressed screen segment, slowly put one end of it into the effective temperature zone of the wire drawing furnace, keep the screen segment warm within the required temperature, melt one end of the screen segment by hot-melt bonding of the glass capillary tube itself until one end of each glass capillary tube is completely closed, so that the opening at one end of the screen segment is melted into one body to realize the sealing of one end of the screen segment;

[0014] Step 6: Slowly cool down to anneal the screen segment to eliminate residual stress and obtain the desired glass capillary array.

[0015] In an optional embodiment, in step S1, the opening area ratio of the glass tube is 60% to 90%, the outer diameter is 20 to 40 mm, and the length is 300 to 500 mm.

[0016] In an optional embodiment, in step S1, the drawing of the glass single tube is carried out at a high temperature of 600 to 2000° C., using a suitable laser or high-pressure cutting method according to the hardness of the material.

[0017] In an optional embodiment, in step S1, the outer diameter of the glass single tube is 0.5-1.5 mm, and the length is 300-500 mm.

[0018] In an optional embodiment, in step S2, the length of the glass multi-tube array is determined according to the length of the screen arrangement mold.

[0019] In an optional embodiment, in step S2, the outer dimensions of the glass multi-tube array are 0.5 to 2 mm, and the pore size of each glass capillary is 10 to 200 μm.

[0020] In an optional embodiment, the cross-sectional shape of the glass capillary is a regular hexagon, a square or a circle; if the cross-sectional shape of the glass capillary is required to be a regular hexagon, the two ends of the glass single tube are first closed by high-temperature melting or filling with epoxy resin, and then the sealed multiple glass single tubes are arranged and bundled and placed in a drawing furnace, and drawn under vacuum.

[0021] In an optional embodiment, in step S4, the vacuum degree is lower than 20 Pa, the preset insulation temperature is 100-200° C. lower than the temperature when drawing the glass single tube, and the insulation time is 1-2 hours.

[0022] In an optional embodiment, in step S5, the insulation temperature of the screen segment is 10-20°C lower than the temperature when drawing the glass single tube. The melting length of the screen segment is 4-8mm as required, and the melting area has a trapezoidal transition.

[0023] In an optional embodiment, in step S6, the cooling rate is precisely controlled to be lower than 1°C / min during annealing.

[0024] In an optional implementation, in step S3, part of the solid glass may be wrapped around the periphery of the screen segment according to the requirements of the application environment.

[0025] In an optional embodiment, the pressure-resistant glass is borosilicate glass, quartz glass or aluminosilicate glass.

[0026] In an optional embodiment, the pressure-resistant glass is borosilicate glass, which comprises the following components in terms of mass percentage:

[0027] SiO2: 40%-60%

[0028] B2O3+Al2O3: 10%-25%

[0029] MgO+CaO: 10%-25%

[0030] BaO+Bi2O3: 5%-10%

[0031] Na2O+K2O:1%-5%.

[0032] According to a second aspect of the present invention, there is provided a glass capillary array for gas storage prepared by the aforementioned method.

[0033] It can be seen from the above technical scheme of the present invention that the present invention abandons the traditional preparation method of filling the microtube gaps with fusible materials such as epoxy rubber, and successfully prepares a glass capillary array for gas storage by combining the screening method and the hot melt method. The method of the present invention adopts a completely different processing principle, based on the hot melt bonding principle of the glass tube itself, and adopts a vacuum melting and pressing method to realize an effective array of multiple glass microtubes. It has the advantage of being integrated, gets rid of the usage restrictions introduced by fillers, and has more diversified application scenarios.

[0034] The glass capillary array for gas storage of the present invention adopts a high-temperature hot-melt design to process the end faces of the glass capillaries into an integrated unit in a sealed manner. Compared with other sealing materials such as indium tin alloy, the sealing has better consistency, better pressure resistance stability in extreme environments, and is easier to achieve in terms of process control. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 It is a process flow chart of the method for preparing the glass capillary array for gas storage of the present invention.

[0036] Figure 2 4 is a flow chart of a method for preparing a glass capillary array for gas storage in an exemplary embodiment of the present invention.

[0037] Figure 3 Schematic diagram of a plurality of glass tubes arranged into a regular hexagonal rod in an exemplary embodiment of the present invention.

[0038] Figure 4 It is a schematic diagram of a plurality of glass single tubes arranged into regular hexagonal rods and drawn into a glass multi-tube array in an exemplary embodiment of the present invention.

[0039] Figure 5 Schematic diagram of the glass capillary array for gas storage obtained in Example 1 of the present invention.

[0040] Figure 6 This is a cross-sectional picture of glass single tubes arranged into regular hexagonal rods in Example 1 of the present invention.

[0041] Figure 7 It is a schematic diagram of the microstructure of the glass capillary array for gas storage obtained in Example 1 of the present invention. DETAILED DESCRIPTION

[0042] In order to better understand the technical content of the present invention, specific embodiments are given and described as follows in conjunction with the accompanying drawings.

[0043] Various aspects of the present invention are described in this disclosure with reference to the accompanying drawings, in which many illustrative embodiments are shown. The embodiments of the present disclosure are not necessarily intended to include all aspects of the present invention. It should be understood that the various concepts and embodiments introduced above, as well as those described in more detail below, can be implemented in any of many ways.

[0044] Combination Figure 1 The process shown, in a preferred embodiment of the present invention, provides a method for preparing a glass capillary array for gas storage, including: preparing glass tubes from pressure-resistant glass, drawing single tubes, combining single tubes, drawing multi-tube arrays, arranging multi-tube arrays, vacuum melting and pressing, hot-melt sealing and other multi-step production processes, and finally preparing a glass capillary array for gas storage to achieve an integrated pressure-resistant design.

[0045] The method for preparing a glass capillary array for gas storage implemented as an example comprises:

[0046] Step 1: Select a pressure-resistant glass material to prepare a glass tube with smooth inner and outer surfaces, and draw the glass tube into a single glass tube at high temperature in a drawing furnace.

[0047] Step 2: Arrange multiple glass single tubes and bundle them with glass wires; place the bundled glass single tube group in a drawing furnace, and draw them into a glass multi-tube array by vacuuming at high temperature; wherein the smallest unit of the glass multi-tube array is a glass capillary.

[0048] Step 3: Arrange the glass multi-tube array row by row into a specific mold. After the arrangement is completed, tighten the mold to form a tightly arranged screen segment.

[0049] Step 4: Place the arranged screen segments into a vacuum melting and pressing system. Based on the hot-melt bonding principle of the glass tubes themselves, pressurize them under a preset temperature and vacuum environment so that all the multiple tubes in the screen segment are melted and pressed into one.

[0050] Step 5. Hang and fix the melted screen segment, and slowly put one end of it into the effective temperature zone of the wire drawing furnace. The screen segment is kept warm within the required temperature. The glass capillary itself is melted by hot-melt bonding until one end of each glass capillary is completely closed, so that the opening at one end of the screen segment is melted into one piece to achieve the sealing of one end of the screen segment.

[0051] Step 6: Anneal the screen segment under precise temperature control to eliminate residual stress and obtain the final capillary array.

[0052] In an optional embodiment, the opening area ratio of the glass tube is 60% to 90%, the outer dimensions are 20 to 40 mm, and the length is 300 to 500 mm. The size of the glass tube determines the opening area ratio parameter of the capillary array. Generally, the opening area ratio is 60% to 90%. As the opening area ratio increases, the hydrogen storage volume increases but the pressure resistance decreases. It is necessary to consider the optimal opening area ratio by combining the mass percentage and volume percentage.

[0053] The opening area ratio of the glass tube = (inner diameter / outer diameter)2 determines the opening area ratio of the final structure.

[0054] In an optional embodiment, the drawing of the glass single tube is carried out at a high temperature of 600 to 2000° C., and a suitable laser or high-pressure cutting method is used according to the hardness of the material to ensure a smooth cutting surface.

[0055] In an optional embodiment, the diameter of the glass single tube is 0.5-1.5 mm and the length is 300-500 mm. Improving the dimensional accuracy and symmetry of the single tube can effectively improve the uniformity of the capillary array.

[0056] In an optional embodiment, laser or high-pressure cutting is used to obtain glass multi-tubes of required length, and the length is determined according to the length of the screen arrangement mold.

[0057] In an optional embodiment, multiple glass tubes are arranged row by row into a specific mold. The mold can be designed to be a regular hexagon, square or circle. After the corresponding arrangement, the shape of the screen segment is consistent with the shape of the mold. The mold has a size adjustment function and the gap can be tightened after the arrangement is completed.

[0058] In a preferred embodiment, the shape of the screen segments after arrangement is: the outer dimension is 20-40 mm, and the length is 100-400 mm.

[0059] In an optional embodiment, the outer dimensions of the glass multi-tube array are 0.5-2 mm, and the pore size of each glass capillary is 10-200 μm, which is used to store gas.

[0060] In an optional embodiment, the cross-sectional shape of the glass capillary is a regular hexagon, a square or a circle.

[0061] It can be understood that when the cross-sectional shape of the glass capillary is square or circular, it corresponds to the cross-sectional shape of the glass single tube; if the cross-sectional shape of the glass capillary is required to be a regular hexagon, it is necessary to first use high-temperature melting or epoxy resin filling to close the two ends of the glass single tube, and perform an airtightness test, and then arrange and bundle the sealed multiple glass single tubes and place them in a drawing furnace. When drawing the bundled glass single tube group, a mechanical pump is introduced to evacuate the single tube group, and the pressure difference can be used to draw the round tube into a uniform regular hexagonal pore structure; when the cross-sectional shape of the glass capillary is a regular hexagon, the structural strength and opening area ratio can be effectively improved, and the hydrogen storage capacity and pressure resistance can be improved.

[0062] It is understandable that when multiple glass tubes are drawn into a glass multi-tube array, the multiple glass tubes can be arranged into any shape and then bundled, such as a regular hexagonal structure, which can be selected according to actual conditions. Glass wire is preferably used for bundling.

[0063] In an optional embodiment, the drawing temperature of the glass multi-tube array is 10-30° C. lower than the drawing temperature of the glass single tube, which is related to the size design.

[0064] In an optional embodiment, the conditions for vacuum melting and pressing are: the vacuum degree is lower than 20 Pa, the preset insulation temperature is 100-200° C. lower than the temperature when drawing the glass single tube, and the insulation time is 1-2 hours.

[0065] In an optional embodiment, the insulation temperature of the screen segment is 10-20°C lower than the temperature when drawing a glass single tube, that is, 500-1800°C. As required, the melting length of the screen segment is 4-8mm, and the melting area has a trapezoidal transition.

[0066] In an optional embodiment, the cooling rate during annealing is precisely controlled to be lower than 1°C / min.

[0067] In an optional implementation, in step S3, part of the solid glass may be wrapped around the periphery of the screen segment according to the application environment requirements to enhance the overall environmental adaptability such as impact resistance and vibration resistance.

[0068] In an optional embodiment, the pressure-resistant glass is borosilicate glass, quartz glass or aluminosilicate glass.

[0069] In an optional embodiment, the pressure-resistant glass is borosilicate glass, which comprises the following components in terms of mass percentage:

[0070] SiO2: 40%-60%

[0071] B2O3+Al2O3: 10%-25%

[0072] MgO+CaO: 10%-25%

[0073] BaO+Bi2O3: 5%-10%

[0074] Na2O+K2O:1%-5%.

[0075] In another exemplary embodiment of the present invention, a glass capillary array for gas storage prepared by the aforementioned method is also provided.

[0076] In an optional embodiment, the open end of the glass capillary array is connected to a high-pressure connector via a sealing material to achieve the function of charging and discharging.

[0077] Combination Figure 2 As shown, the method for preparing a glass capillary array for gas storage according to an exemplary embodiment of the present invention is as follows:

[0078] Glass raw materials with appropriate composition are selected and processed into a round glass tube shape with uniform size, an opening area ratio of 60% to 90%, an outer shape of 20 to 40 mm, and a length of 300 to 500 mm.

[0079] The glass tube is placed in a high-temperature furnace of a wire drawing machine, and drawn into a single tube with an outer diameter of 0.5 to 1.5 mm and a circular cross-sectional shape at a high temperature of 600 to 2000°C according to the physical properties of the material. The single tube is cut into lengths of 300 to 500 mm using a high-pressure cutting method.

[0080] The two ends of the glass single tube are sealed with high temperature.

[0081] Arrange multiple glass tubes with closed ends into a regular hexagonal outline in the manner of arranging the required number of glass tubes on each side of the outermost circle, and then continue to arrange glass tubes with closed ends in the outline until it is completely filled, and combine them into a regular hexagonal rod, for example, Figure 3 As shown, there are 12 glass tubes arranged in the outermost circle on each side, and the number of glass tubes in the outermost circle can be increased or decreased according to the example requirements.

[0082] After that, it is tied with a glass wire and placed in a drawing furnace. It is drawn at a temperature 10 to 30°C lower than the drawing temperature of the glass single tube. The drawing process is kept in a vacuum state. The round glass single tube is processed into a regular hexagonal glass multi-tube array (such as Figure 4 shown).

[0083] The outer dimensions of the glass multi-tube array are 0.5 to 2 mm, and the smallest unit in the glass multi-tube array is a glass capillary tube with a regular hexagonal cross section.

[0084] Put the regular hexagonal multi-tubes into a regular hexagonal screen arrangement mold and arrange them into screen segments with opposite side dimensions of 20 to 40 mm and a length of 100 to 400 mm to obtain regular hexagonal screen segments.

[0085] The arranged regular hexagonal screen segments are placed in a vacuum melting and pressing system with the vacuum degree controlled below 20Pa. A certain pressure is applied at a temperature 100-200°C lower than the drawing temperature of a single glass tube and kept warm for 1-2 hours to fuse the multi-tube array into a whole. The temperature is slowly lowered to eliminate residual stress. At this time, the smallest unit is a glass capillary with a regular hexagonal cross-section and the pore diameter of the glass capillary is 10-200μm.

[0086] Put one end of the melted and pressed screen segment into the temperature zone of the drawing furnace and keep it warm for 1 to 2 hours at a temperature 10 to 20°C lower than the drawing temperature of the glass single tube. Melt and close one end of the screen segment in the furnace, and the size of the closed end will slowly transition. The transition zone will be transparent and the regular hexagonal shape of the screen segment will be basically maintained.

[0087] Then, the temperature is slowly lowered at a cooling rate lower than 1°C / min to eliminate the residual stress, thereby obtaining a glass capillary array for gas storage.

[0088] The outer dimensions in the present invention refer to the outer diameter of the glass tube.

[0089] For better understanding, the present invention is further described below in conjunction with several specific examples, but the processing technology is not limited thereto, and the content of the present invention is not limited thereto.

[0090] In the following Examples 1-3, the cross-section of the smallest unit of the glass capillary array for gas storage is a regular hexagon as an example for explanation, and the glass composition is selected as shown in Table 1.

[0091] Table 1

[0092]

[0093]

[0094] Example 1

[0095] The raw material of glass 1 component is selected and processed into a round glass tube shape with uniform size, an opening area ratio of 60%, an outer dimension of 40 mm, and a length of 300 mm.

[0096] The glass tube is placed in a high-temperature furnace of a wire drawing machine. According to the physical properties of the material, it is drawn at a high temperature of 700°C into a glass single tube with an outer diameter of 0.5mm and a circular cross-sectional shape. The glass single tube is cut into a length of 300mm using a high-pressure cutting method.

[0097] The two ends of the glass single tube are sealed by high-temperature sealing.

[0098] A plurality of glass single tubes with closed end faces are arranged into a regular hexagonal outline in the form of 18 glass single tubes arranged in the outermost circle on each side, and then the glass single tubes with closed end faces are continued to be arranged within the outline until it is completely filled, and are combined into a regular hexagonal rod. After being tied with a glass wire, they are placed in a wire drawing furnace and drawn at a high temperature of 670°C. The drawing process is kept in a vacuum state throughout the drawing process, and the vacuum rate is 2L / s. The circular glass single tube is processed into a regular hexagonal glass multi-tube array by utilizing the pressure difference between the inside and outside of the closed single tube. The outer dimension of the glass multi-tube array is 0.52mm. At this time, the smallest unit in the glass multi-tube array is a glass capillary with a regular hexagonal cross-section.

[0099] The regular hexagonal glass multi-tube array is placed into a regular hexagonal screen arrangement mold and arranged into screen segments with opposite sides of 35 mm and a length of 300 mm to obtain a regular hexagonal screen segment.

[0100] The arranged regular hexagonal screen segments are placed in a vacuum melting and pressing system with the vacuum degree controlled below 20Pa. A certain pressure is applied at a high temperature of 500°C and kept warm for 1 hour to fuse the glass multi-tube array into a whole. The temperature is slowly lowered to eliminate residual stress. At this time, the smallest unit is a glass capillary with a regular hexagonal cross-section and a pore diameter of 10μm.

[0101] Put one end of the melted and pressed screen segment into the temperature zone of the wire drawing furnace and keep it at 700℃ for 1 hour. Melt and close one end of the screen segment in the furnace. The size of the closed end slowly transitions and the transition zone becomes transparent, basically maintaining the regular hexagonal shape of the screen segment.

[0102] Then, the temperature is slowly lowered at a cooling rate of 0.5°C / min to eliminate the residual stress, and a glass capillary array for gas storage can be obtained.

[0103] Example 2

[0104] The raw material of glass 2 components is selected and processed into a round glass tube shape with uniform size, an opening area ratio of 65%, an outer dimension of 20 mm, and a length of 500 mm.

[0105] The glass tube is placed in a high-temperature furnace of a wire drawing machine. According to the physical properties of the material, it is drawn at a high temperature of 680°C into a glass single tube with an outer diameter of 0.8mm and a circular cross-sectional shape. The single tube is cut into a length of 500mm using a high-pressure cutting method.

[0106] The two ends of the glass tube are sealed with epoxy resin.

[0107] A plurality of glass single tubes with closed end faces are arranged into a regular hexagonal outline in the form of 24 glass single tubes arranged in the outermost circle on each side, and then the glass single tubes with closed end faces are continued to be arranged within the outline until it is completely filled, and are combined into a regular hexagonal rod. After being tied with a glass wire, they are placed in a wire drawing furnace and drawn at a high temperature of 670°C. The drawing process is kept in a vacuum state throughout the drawing process, and the vacuum rate is 2L / s. The circular glass single tube is processed into a regular hexagonal glass multi-tube array by utilizing the pressure difference between the inside and outside of the closed single tube. The outer dimension of the glass multi-tube array is 0.83mm. At this time, the smallest unit in the glass multi-tube array is a glass capillary with a regular hexagonal cross-section.

[0108] The regular hexagonal glass multi-tube array is placed into a regular hexagonal screen arrangement mold and arranged into screen segments with opposite sides of 40 mm and a length of 300 mm to obtain a regular hexagonal screen segment.

[0109] The arranged regular hexagonal screen segments are placed in a vacuum melting and pressing system with the vacuum degree controlled below 20Pa. A certain pressure is applied at a high temperature of 530°C and kept warm for 1 hour to fuse the glass multi-tube array into a whole. The temperature is slowly lowered to eliminate residual stress. At this time, the smallest unit is a glass capillary with a regular hexagonal cross-section and a pore diameter of 20μm.

[0110] Put one end of the melted and pressed screen segment into the temperature zone of the wire drawing furnace and keep it at 680℃ for 2 hours. Melt and close one end of the screen segment in the furnace. The size of the closed end slowly transitions and the transition zone becomes transparent, basically maintaining the regular hexagonal shape of the screen segment.

[0111] Then, the temperature is slowly lowered at a cooling rate of 0.5°C / min to eliminate the residual stress, and a glass capillary array for gas storage can be obtained.

[0112] Example 3

[0113] The raw materials of glass 3 components are selected and processed into a round glass tube shape with uniform size, an opening area ratio of 65%, an outer dimension of 30mm and a length of 400mm.

[0114] The glass tube is placed in a high-temperature furnace of a wire drawing machine. According to the physical properties of the material, it is drawn at a high temperature of 660°C into a single tube with an outer diameter of 1.5 mm and a circular cross-sectional shape. The single tube is cut into a length of 400 mm using a high-pressure cutting method.

[0115] The two ends of the glass single tube are sealed with high temperature.

[0116] A plurality of glass single tubes with closed end faces are arranged into a regular hexagonal outline in the form of 30 glass single tubes arranged in the outermost circle on each side, and then the glass single tubes with closed end faces are continued to be arranged within the outline until it is completely filled, and are combined into a regular hexagonal rod. After being tied with a glass wire, they are placed in a wire drawing furnace and drawn at a high temperature of 640°C. The drawing process is kept in a vacuum state throughout the drawing process, and the vacuum rate is 2L / s. The circular glass single tube is processed into a regular hexagonal glass multi-tube array by utilizing the pressure difference between the inside and outside of the closed single tube. The outer dimension of the glass multi-tube array is 1.3mm. At this time, the smallest unit in the glass multi-tube array is a glass capillary with a regular hexagonal cross-section.

[0117] Put the regular hexagonal multi-tubes into a regular hexagonal screen arrangement mold and arrange them into screen segments with opposite sides of 40 mm and a length of 300 mm to obtain regular hexagonal screen segments.

[0118] The arranged regular hexagonal screen segments are placed in a vacuum melting and pressing system with the vacuum degree controlled below 20Pa. A certain pressure is applied at a high temperature of 560°C and kept warm for 1 hour to fuse the multi-tube array into a whole. The temperature is slowly lowered to eliminate residual stress. At this time, the smallest unit is a glass capillary with a regular hexagonal cross-section and a pore diameter of 50μm.

[0119] Put one end of the melted and pressed screen segment into the temperature zone of the wire drawing furnace and keep it at 650℃ for 1 hour. Melt and close one end of the screen segment in the furnace. The size of the closed end slowly transitions and the transition zone becomes transparent, basically maintaining the regular hexagonal shape of the screen segment.

[0120] Then, the temperature is slowly lowered at a cooling rate of 0.5°C / min to eliminate the residual stress, and a glass capillary array for gas storage can be obtained.

[0121] Combination Figure 5 The figure shows an example of a glass capillary array for gas storage prepared in Example 1, which contains only one glass material and is tightly bonded through a hot melt process. The transparent part is a molten closed end and is wrapped outside the effective area in an integrated structure, which greatly improves the environmental adaptability and can be used in extreme scenarios.

[0122] Combination Figure 6 and Figure 7 As shown in the microstructure diagram of the glass capillary array for gas storage prepared in Example 1, it can be seen that the glass capillary array for gas storage is successfully prepared by the method of the present invention, and by sealing both ends of the glass single tube and then arranging and drawing it, the cross-section of the smallest unit of the capillary array can be made into a regular hexagonal structure.

[0123] From the above, it can be seen that the present invention successfully prepares a glass capillary array for gas storage by combining a screen arrangement method and a hot melt method. The obtained glass capillary array has only one medium, glass material, which can effectively improve the overall pressure resistance of the glass capillary, eliminate the environmental restrictions brought by other sealed materials, and improve environmental adaptability.

[0124] Although the present invention has been disclosed as above with preferred embodiments, it is not intended to limit the present invention. A person with ordinary knowledge in the technical field to which the present invention belongs may make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention shall be determined by the definition of the claims.

Claims

1. A method for preparing a glass capillary array for gas storage, characterized in that: The following steps are involved: Step 1, selecting a pressure-resistant glass material to prepare a glass tube with smooth inner and outer surfaces, drawing the glass tube in a drawing furnace and cutting it into a single glass tube; Step 2, closing the two ends of the glass single tube by high-temperature melting or filling epoxy resin, arranging and bundling the sealed multiple glass single tubes and placing them in a drawing furnace, and drawing them under vacuum. The pressure difference can be used to draw the glass capillary into a uniform regular hexagonal pore structure to improve the hydrogen storage capacity and pressure resistance, and the glass capillary can be cut into a required length to obtain multiple glass multi-tube arrays; wherein the smallest unit of the glass multi-tube array is the glass capillary; Step 3: Arrange the glass multi-tube arrays row by row into the screen arrangement mold, and tighten the mold after the arrangement is completed to form closely arranged screen segments; Step 4: Place the arranged screen segments into a vacuum melting and pressing system, and pressurize them under a preset temperature and vacuum environment so that all the glass capillaries in the screen segments are melted and pressed into one; Step 5, hang and fix the melted and pressed screen segment, slowly put one end of it into the effective temperature zone of the wire drawing furnace, keep the screen segment warm within the required temperature, melt one end of the screen segment by hot-melt bonding until one end of each glass capillary is completely closed, so that the opening at one end of the screen segment is melted into one to achieve the sealing of one end of the screen segment; wherein, the heat preservation temperature of the screen segment is 10-20°C lower than the temperature when drawing a single glass tube, the melting length of the screen segment is 4-8mm as required, and the melting area is trapezoidal transition; Step 6: Slowly cool down to anneal the screen segment to eliminate residual stress and obtain the desired glass capillary array, wherein the cooling rate is precisely controlled to be lower than 1°C / min during annealing.

2. The method for preparing a glass capillary array for gas storage according to claim 1, characterized in that: In the step S1, the opening area ratio of the glass tube is 60% to 90%, the outer diameter is 20 to 40 mm, and the length is 300 to 500 mm.

3. The method for preparing a glass capillary array for gas storage according to claim 1, characterized in that: In the step S1, the drawing of the glass single tube is carried out at a high temperature of 600-2000° C., and a suitable laser or high-pressure cutting method is adopted according to the hardness of the material.

4. The method for preparing a glass capillary array for gas storage according to claim 1, characterized in that: In the step S1, the outer diameter of the glass single tube is 0.5-1.5 mm, and the length is 300-500 mm.

5. The method for preparing a glass capillary array for gas storage according to claim 1, characterized in that: In step S2, the length of the glass multi-tube array is determined according to the length of the screen arrangement mold.

6. The method for preparing a glass capillary array for gas storage according to claim 1, characterized in that: In step S2, the outer dimensions of the glass multi-tube array are 0.5-2 mm, and the aperture size of each glass capillary is 10-200 μm.

7. The method for preparing a glass capillary array for gas storage according to claim 6, characterized in that: The two ends of the glass tube are closed by high-temperature melting or filling with epoxy resin, and then the sealed glass tubes are arranged and bundled and placed in a drawing furnace, and drawn under vacuum to make the cross-sectional shape of the glass capillary tube a regular hexagon.

8. The method for preparing a glass capillary array for gas storage according to claim 1, characterized in that: In step S4, the insulation time is 1 to 2 hours.

9. The method for preparing a glass capillary array for gas storage according to claim 1, characterized in that: In the step S3, part of the solid glass may be wrapped around the periphery of the screen segment according to the application environment requirements.

10. The method for preparing a glass capillary array for gas storage according to any one of claims 1 to 9, characterized in that: The pressure-resistant glass is borosilicate glass, quartz glass or aluminosilicate glass.

11. The method for preparing a glass capillary array for gas storage according to any one of claims 1 to 9, characterized in that: Pressure-resistant glass is borosilicate glass, which contains the following components by mass percentage: SiO2: 40%-60% B2O3+Al2O3:10%-25% MgO+CaO: 10%-25% BaO+Bi2O3:5%-10% Na2O+K2O:1%-5%.

12. A glass capillary array for gas storage prepared by the method according to any one of claims 1 to 11.

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