Heating device and method for pressure reaction kettle

Abstract

The invention relates to the technical field of heating furnaces, in particular to a heating device and method for a pressure reaction kettle. The heating device comprises a furnace body, wherein the furnace body comprises an upper furnace shell, a lower furnace shell and a heat insulation ring; a bearing ring is installed on the upper portion of the upper furnace shell, a top cover is installed on the top of the upper furnace shell, and a bottom plate is installed at the bottom of the lower furnace shell. The heat insulation ring is clamped between the upper furnace shell and the lower furnace shell; a plurality of heating units are arranged on the inner side of the upper furnace shell and the inner side of the lower furnace shell; first adjusting screw rods in one-to-one correspondence with the heating units are in threaded connection in the upper furnace shell; second adjusting screw rods in one-to-one correspondence with the heating units are in threaded connection in the lower furnace shell; and temperature monitoring assemblies are mounted in the upper furnace shell and the lower furnace shell. The heating device can uniformly heat the pressure reaction kettle in the axial direction and the circumferential direction; under the condition that a certain heating unit is suddenly damaged, the uniform axial heating effect can be kept by adjusting the height positions of other heating units.

Description

Technical Field

[0001] This invention relates to the field of heating furnace technology, and more specifically to a heating device and method for a pressure reactor. Background Technology

[0002] With the development of science and technology, semiconductor materials are closely related to people's lives. Gallium nitride (GaN), as a representative of third-generation semiconductor materials, has the advantages of wide bandgap, low dielectric constant, high electron mobility, high thermal conductivity and radiation resistance, and is widely used in optoelectronic devices and microelectronics.

[0003] Currently, the main methods for preparing GaN single crystal materials include hydride vapor phase epitaxy, ammonothermal method, and flux method. Among them, the ammonothermal method for preparing GaN single crystal materials is expected to become the main method for commercial production due to its advantages of high crystal quality, ease of large-scale production, and low cost. The principle of the ammonothermal method for preparing GaN single crystal materials is as follows: by controlling the temperature, the pressure reactor is divided into two regions with different temperatures: a dissolution region and a growth region. The convection generated by the temperature difference between the dissolution region and the growth region transports the dissolved Ga source (polycrystalline GaN or Ga) to the growth region, causing supersaturation in this region, thereby crystallizing and growing GaN.

[0004] Accordingly, to facilitate segmented temperature control of the furnace, heating units are typically set up in the dissolution zone and the growth zone, and their heating temperatures are adjusted separately to create the required temperature difference. For example, a segmented homogenizing furnace disclosed in Chinese Patent CN202311518127.8, by setting up multiple individually controlled heating units, can effectively achieve separate temperature control of the dissolution zone and the growth zone. However, if one of the heating units in this furnace suddenly fails and cannot heat, a local cold zone will form near that unit, causing a change in the temperature field inside the furnace and disrupting the solute migration driven by the temperature difference. This results in a local decrease or cessation of the GaN growth rate, leading to an increase in crystal defects, a rise in dislocation density, and even inducing non-directional nucleation. In this situation, if the furnace is shut down and the heating unit is replaced, the solute migration is interrupted during the shutdown, and the local growth on the crystal surface is not completed. This will freeze lattice defects, vacancies, or impurities, resulting in rough interfaces or growth streaks. After subsequent repair and reheating, the crystal will continue to grow on the "old interface," but the roughness and defect density of this interface are often high, which can easily lead to poor bonding between the old and new crystal regions and affect the integrity of the single crystal. If the power of the adjacent heating unit is gradually increased to compensate, the temperature rise in the area near the adjacent heating unit may cause thermal stress concentration, leading to defects such as cracks and dislocations in the GaN crystal. Summary of the Invention

[0005] The purpose of this invention is to provide a heating device and method for a pressure reactor, which can uniformly heat the pressure reactor in both the axial and circumferential directions; and in the event that a heating unit suddenly fails and cannot continue heating, the remaining heating units can still be evenly distributed in the vertical direction by adjusting the height of other heating units, thereby ensuring a uniform heating effect in the longitudinal direction and providing a uniform heating area.

[0006] This invention provides a heating device for a pressure reactor, comprising a furnace body including an upper furnace shell, a lower furnace shell, and a heat insulation ring coaxially mounted; a bearing ring fixedly mounted on the upper part of the upper furnace shell, a top cover detachably mounted on the top of the upper furnace shell, and a bottom plate fixedly mounted on the bottom of the lower furnace shell; the heat insulation ring is sandwiched between the bottom of the upper furnace shell and the top of the lower furnace shell; multiple heating units are slidably arranged vertically on the inner sides of both the upper and lower furnace shells; and a first adjusting screw is vertically mounted on the inner side of the upper furnace shell. A plurality of first adjusting screws are provided, each first adjusting screw being threadedly connected to a heating unit on the inner side of the upper furnace shell, and each first adjusting screw being rotatably connected to the bearing ring; a plurality of second adjusting screws are vertically provided on the inner side of the lower furnace shell, each second adjusting screw being threadedly connected to a heating unit on the inner side of the lower furnace shell, and each second adjusting screw being rotatably connected to the bottom plate; and a temperature monitoring component is installed on both the inner sides of the upper and lower furnace shells.

[0007] Furthermore, a top cover is detachably installed above the top cover, and a bottom cover is detachably installed below the bottom plate; the upper part of the first adjusting screw passes through the top cover and is located inside the top cover, and the lower part of the second adjusting screw passes through the bottom plate and is located inside the bottom cover.

[0008] Furthermore, the temperature monitoring component includes a mounting rod and several temperature sensors. The mounting rod is vertically arranged, and each of the temperature sensors is evenly distributed along the axial direction of the mounting rod. For the temperature monitoring component inside the upper furnace shell, its mounting rod is rotatably mounted on the bearing ring, and its upper end penetrates the top cover and is located inside the top cover. For the temperature monitoring component inside the lower furnace shell, its mounting rod is rotatably mounted on the bottom plate, and its lower end penetrates the bottom plate and is located inside the bottom cover.

[0009] Furthermore, the heating unit includes a mounting ring and a heating wire; the mounting ring is used to slide and connect with the upper furnace shell or the lower furnace shell, and is used to thread and connect with the first adjusting screw or the second adjusting screw; multiple fixing members are evenly distributed in a spiral array along the axial direction on the inner circumferential surface of the mounting ring, and the heating wire passes through each of the fixing members one by one, with the projections of the two ends of the heating wire on the end face of the mounting ring coinciding.

[0010] Furthermore, the cross-sectional area of ​​the heating wire section between two adjacent fixing members satisfies: , in, A For any point on this heating wire section P Cross-sectional area at the location, A 0 This is the cross-sectional area at the midpoint of the heating wire section. R This refers to the distance between the heating wire at the fixing point and the axis of the mounting ring. n For the number of fasteners, α The coefficient is 1.5 < α <2, x For this point P Distance to the midpoint r The outer diameter is the pressure vessel to be heated.

[0011] Furthermore, the fastener is made of ceramic; a through hole is formed on the fastener along the direction of the fastener array, and a slot is formed above the fastener, the slot connecting to the through hole.

[0012] Another aspect of the present invention provides a heating method for a pressure reactor. Based on the aforementioned heating device, the heating method includes: hoisting and installing the pressure reactor into the furnace body, such that the pressure reactor is coaxial with the lower furnace shell; controlling each of the heating units to heat, such that the temperature of the reactor inside the upper furnace shell reaches a first preset temperature and is maintained, and the temperature of the reactor inside the lower furnace shell reaches a second preset temperature and is maintained; wherein the first preset temperature is lower than the second preset temperature; during the heating process of each of the heating units, controlling the heating power of at least one heating unit at the bottom of the upper furnace shell to be lower than the heating power of other heating units inside the upper furnace shell; and controlling the heating power of at least one heating unit at the top of the lower furnace shell to be higher than the heating power of other heating units inside the lower furnace shell.

[0013] Furthermore, the temperature monitoring component is controlled to continuously monitor the measured temperature at multiple monitoring points on the outer wall of the pressure reactor; if the measured temperature at any monitoring point deviates from the target temperature by more than 10°C, the power of at least one heating unit near that monitoring point is adjusted; including: if the measured temperature is greater than the target temperature, the power of at least one heating unit at that location is reduced, and if the measured temperature is less than the target temperature, the power of at least one heating unit at that location is increased.

[0014] Furthermore, if any heating unit is damaged during the heating process of each of the heating units, the height position of other heating units located on the same inner side of the furnace shell as the damaged heating unit is adjusted so that the other heating units are evenly distributed in the vertical direction.

[0015] Further, for each heating unit inside the upper furnace shell, the distance between the uppermost heating unit and the supporting ring is equal to the distance between the lowermost heating unit and the insulation ring, which is equal to half the distance between two adjacent heating units; for each heating unit inside the lower furnace shell, the distance between the uppermost heating unit and the insulation ring is equal to the distance between the lowermost heating unit and the bottom plate, which is equal to half the distance between two adjacent heating units; adjusting the height position of other heating units located on the same furnace shell as the damaged heating unit includes: adjusting the height position of each heating unit by rotating the first adjusting screw or the second adjusting screw corresponding to the other heating unit; the height adjustment amount of each heating unit satisfies: , in, ΔH The height adjustment amount of the heating unit to be adjusted. j The serial number of the heating unit to be adjusted. H This refers to the inner cavity height of the furnace shell. N To adjust the number of front heating units, i This is the serial number of the damaged heating unit.

[0016] Compared with the prior art, the present invention has the following advantages and beneficial effects: 1. The present invention provides a heating device and method for a pressure reactor. By sliding heating units inside both the upper and lower furnace shells vertically, and determining the height of each heating unit using first and second adjusting screws, the heating units are uniformly distributed vertically, thus uniformly heating the internal pressure reactor axially. Furthermore, if any heating unit suddenly fails during the heating process, the height of the other heating units inside the furnace shell corresponding to the damaged unit is adjusted by rotating the corresponding first or second adjusting screw, ensuring that the other heating units remain uniformly distributed vertically. For the preparation of GaN single crystal materials using the ammonothermal method in a pressure reactor, this invention can continue to provide a uniform heating temperature field for the dissolution or growth zones even when a heating unit in the furnace shell corresponding to the dissolution or growth zone fails to heat, thereby maintaining stable crystal growth and greatly reducing the impact of this situation on the quality of the single crystal material generated inside the reactor. 2. The present invention provides a heating device and method for a pressure reactor, which, by changing the cross-sectional area of ​​the heating wire, gradually increases the heating power of the heating wire section between two adjacent fixing parts from the midpoint to the fixing part, thereby compensating for the attenuation of radiation intensity of the heating wire near the fixing part due to its greater distance from the pressure reactor, and can uniformly heat the pressure reactor in the circumferential direction. 3. The present invention provides a heating device and method for a pressure reactor. By setting the distance between the uppermost heating unit and the support ring to be equal to the distance between the lowermost heating unit and the insulation ring, which is equal to half the distance between two adjacent heating units, the temperature at both ends of the inner cavity of the furnace shell is prevented from being too low or too high. It can accurately determine the height adjustment required for other heating units if any heating unit is damaged during the heating process, thus facilitating the adjustment of the heating units that still have intact heating functions to be evenly distributed in the vertical direction. It is worth noting that the height of each heating unit is adjusted by using a first adjusting screw or a second adjusting screw, without involving electrical drive, which can better adapt to the high temperature environment inside the furnace, and thus reliably realize the adjustment of the height position of the heating unit during the heating process. Attached Figure Description

[0017] The accompanying drawings, which are included to provide a further understanding of embodiments of the invention and form part of this application, do not constitute a limitation thereof. In the drawings: Figure 1 A three-dimensional structural schematic diagram of the heating device for a pressure reactor according to an embodiment of the present invention; Figure 2 According to Figure 1 Draw a magnified view of area A; Figure 3 A longitudinal sectional view of the heating device for a pressure reactor according to an embodiment of the present invention; Figure 4 According to Figure 3 Draw a magnified view of area B; Figure 5 Another longitudinal sectional view of the heating device for a pressure reactor according to an embodiment of the present invention; Figure 6 A three-dimensional structural schematic diagram of a heating unit according to an embodiment of the present invention; Figure 7 A schematic diagram illustrating a scenario of a heating unit heating a pressure reactor according to an embodiment of the present invention; Figure 8 According to Figure 3 Draw a magnified view of region C.

[0018] The attached diagram shows the markings and corresponding component names: 11-Upper furnace shell; 12-Lower furnace shell; 13-Heat insulation ring; 14-Support ring; 15-Top cover; 16-Bottom plate; 17-Top cover; 18-Bottom cover; 19-Pressure reactor; 2-Heating unit; 21-Mounting ring; 22-Heating wire; 23-Fixing component; 31-First adjusting screw; 32-Second adjusting screw; 41-Mounting rod; 42-Temperature sensor. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to embodiments and accompanying drawings. The illustrative embodiments and descriptions of this invention are for illustrative purposes only and are not intended to limit the invention. It should be noted that this invention is already in the actual research and development stage.

[0020] Gallium nitride (GaN), as a representative of third-generation semiconductor materials, possesses advantages such as a wide bandgap, low dielectric constant, high electron mobility, high thermal conductivity, and radiation resistance, and is widely used in optoelectronic devices and microelectronics. Currently, the main methods for preparing GaN single crystal materials include hydride vapor phase epitaxy, ammonothermal method, and flux method. Among these, the ammonothermal method for preparing GaN single crystal materials is expected to become the main method for commercial production due to its advantages of high crystal quality, ease of large-scale production, and low cost. The principle of the ammonothermal method for preparing GaN single crystal materials is as follows: by controlling the temperature, the pressure reactor is divided into two regions with different temperatures: a dissolution region and a growth region. The convection generated by the temperature difference between the dissolution and growth regions transports the dissolved Ga source (polycrystalline GaN or Ga) to the growth region, causing supersaturation in this region, thereby crystallizing and growing GaN.

[0021] Correspondingly, in the preparation of GaN single crystal materials via the ammonothermal method, to facilitate segmented temperature control of the furnace, heating units are typically set up in the dissolution zone and the growth zone, and their heating temperatures are adjusted separately to create the required temperature difference. For example, a segmented homogenizing furnace disclosed in Chinese Patent CN202311518127.8, by setting up multiple individually controlled heating units, can effectively achieve separate temperature control of the dissolution zone and the growth zone. However, if one of the heating units in this furnace suddenly fails and cannot heat, a local cold zone will form near that unit, causing a change in the temperature field within the furnace and disrupting the solute migration driven by the temperature difference. This results in a local decrease or cessation of the GaN growth rate, leading to an increase in crystal defects, a rise in dislocation density, and even inducing non-directional nucleation.

[0022] In this situation, if the furnace is shut down and the heating unit is replaced, the solute migration is interrupted during the shutdown, and the local growth on the crystal surface is not completed. This will freeze lattice defects, vacancies, or impurities, resulting in rough interfaces or growth streaks. After subsequent repair and reheating, the crystal will continue to grow on the "old interface." However, the roughness and defect density of this interface are often high, which can easily lead to poor bonding between the old and new crystal regions and affect the integrity of the single crystal. If the problem is compensated by gradually increasing the power of adjacent heating units, the temperature rise in the area near the adjacent heating units may cause thermal stress concentration, leading to defects such as cracks and dislocations in the GaN crystal. It will also disrupt the original temperature field distribution in the pressure reactor and disrupt the temperature gradient-driven movement of the Ga source.

[0023] Therefore, the present invention proposes a heating device and method for a pressure reactor, which can uniformly heat the pressure reactor in both the axial and circumferential directions; especially for the situation where "a certain heating unit suddenly fails and cannot heat", the remaining heating units can still be evenly distributed in the vertical direction by adjusting the height position of other heating units, thereby maintaining a uniform axial heating effect, which is beneficial to maintaining the original temperature field distribution in the pressure reactor.

[0024] Example 1: like Figures 1 to 5 As shown, this embodiment provides a heating device for a pressure reactor, the heating device comprising: The furnace body includes an upper furnace shell 11, a lower furnace shell 12, and a heat insulation ring 13 coaxially mounted; a bearing ring 14 is fixedly installed on the upper part of the upper furnace shell 11, a top cover 15 is detachably installed on the top of the upper furnace shell 11, and a bottom plate 16 is fixedly installed on the bottom of the lower furnace shell 12; the heat insulation ring 13 is sandwiched between the bottom of the upper furnace shell 11 and the top of the lower furnace shell 12. Heating unit 2, multiple heating units 2 are slidably arranged in the vertical direction on the inner side of the upper furnace shell 11 and the inner side of the lower furnace shell 12; First adjusting screw 31: Multiple first adjusting screws 31 are vertically arranged inside the upper furnace shell 11. Each first adjusting screw 31 is threadedly connected to the heating unit 2 inside the upper furnace shell 11 in a one-to-one correspondence. Each first adjusting screw 31 is rotatably connected to the bearing ring 14. Multiple second adjusting screws 32 are vertically arranged inside the lower furnace shell 12. Each second adjusting screw 32 is threadedly connected to a heating unit 2 inside the lower furnace shell 12 in a one-to-one correspondence, and each second adjusting screw 32 is rotatably connected to the base plate 16; and, Temperature monitoring components are installed on the inner side of both the upper furnace shell 11 and the lower furnace shell 12.

[0025] In one specific practice of this embodiment, the pressure reactor 19 to be heated is cylindrical, and both the upper furnace shell 11 and the lower furnace shell 12 are tubular (e.g., Figure 1 As shown, the internal structure of the heating device is illustrated in the diagram. Figure 1 (Part of the structure was cut off during the drawing). It should be understood that, in order to reduce heat loss to the outside, in this embodiment, the upper furnace shell 11, lower furnace shell 12, heat insulation ring 13, top cover 15, and bottom plate 16 all have heat insulation properties. For example, they include a high-temperature resistant layer, a heat insulation layer, and a rigid support layer sequentially from the inside to the outside (from the side closer to the heating unit 2 to the side closer to the outside). The section of the first adjusting screw 31 located inside the upper furnace shell 11 and the section of the second adjusting screw 32 located inside the lower furnace shell 12 are threaded for threaded connection with the corresponding heating unit 2. Taking the inner side of the furnace shell 11 as an example, the length of the threaded section of each first adjusting screw 31 is equal to the inner cavity height of the upper furnace shell 11 (meaning that the two are approximately equal; there should be a gap between the lower end of the first adjusting screw 31 and the heat insulation ring 13, so as to avoid the first adjusting screw 31 from being affected by the heat insulation ring 13 due to the first adjusting screw 31 abutting against the heat insulation ring 13, and also to avoid the heat insulation ring 13 from being damaged due to the first adjusting screw 31 rotating while abutting against the heat insulation ring 13). Each first adjusting screw 31 is only threaded to one heating unit 2 corresponding to it, and avoidance holes are provided on other heating units 2 to avoid the first adjusting screw 31. The inner circumferential surface of the heat insulation ring 13 is adapted to the outer circumferential surface of the pressure reactor 19, thereby better isolating the heat conduction between the upper furnace shell 11 and the lower furnace shell 12 (meaning preventing temperature conduction through the gap between the heat insulation ring 13 and the pressure reactor 19); the support ring 14 is a rigid ring, and the inner circumferential surface of the support ring 14 is adapted to the outer circumferential surface of the pressure reactor 19. On the one hand, when the pressure reactor 19 is hoisted into the furnace body, the inner circumferential surface of the support ring 14 is used to guide the pressure reactor 19, which can prevent the pressure reactor 19 from touching and damaging the heating unit 2 and / or the heat insulation ring 13 during the hoisting process. On the other hand, the support ring 14 bears the weight of the pressure reactor 19, thereby making the bottom of the pressure reactor 19 suspended (meaning there is a gap between the bottom of the pressure reactor 19 and the bottom plate 16), which can make the bottom of the pressure reactor 19 fully heated.

[0026] Accordingly, this embodiment provides a heating device for a pressure reactor. By sliding the heating units 2 inside the upper furnace shell 11 and lower furnace shell 12 vertically, and determining the height position of each heating unit 2 using first adjusting screws 31 and second adjusting screws 32, the heating units 2 are evenly distributed vertically, thereby uniformly heating the internal pressure reactor 19 axially. Furthermore, in the event that any heating unit 2 suddenly fails during the heating of the pressure reactor 19 and cannot heat, the corresponding first adjusting screw can be rotated to... By adjusting screw 31 or second adjusting screw 32, the height of other heating units 2 inside the furnace shell corresponding to the damaged heating unit 2 is adjusted, thereby ensuring that the other heating units 2 are still evenly distributed in the vertical direction (i.e., in the case where a heating unit 2 is damaged and cannot be heated, forming a cold zone, by adjusting the height of other heating units 2 with intact heating function, the heat source is still evenly distributed in the vertical direction inside the furnace shell, thereby continuing to provide uniform axial heating to the pressure reactor 19). This ensures that the temperature inside the furnace shell remains uniform in the vertical direction. For the preparation of GaN single crystal materials based on the ammonothermal method using the pressure reactor 19, even when a heating unit 2 in the furnace shell corresponding to the dissolution zone or growth zone is damaged and cannot be heated, a uniform heating temperature field can still be provided to the dissolution zone and growth zone respectively, thereby maintaining stable crystal growth and greatly reducing the impact of this situation on the quality of the single crystal material generated in the reactor.

[0027] Preferably, a top cover 17 is detachably installed above the top cover 15, and a bottom cover 18 is detachably installed below the bottom plate 16; The upper part of the first adjusting screw 31 passes through the top cover 15 and is located inside the top cover 17, and the lower part of the second adjusting screw 32 passes through the bottom plate 16 and is located inside the bottom cover 18.

[0028] Similarly, the top cover 17 and the bottom cover 18 also have heat insulation properties, thereby reducing the outward dissipation of heat from the first adjusting screw 31 and the second adjusting screw 32.

[0029] Accordingly, when it is necessary to adjust the height position of the heating unit 2 inside the upper furnace shell 11, the top cover 17 is removed, and the corresponding first adjusting screw 31 is rotated to adjust the height position of the heating unit 2; when it is necessary to adjust the height position of the heating unit 2 inside the lower furnace shell 12, the bottom cover 18 is removed, and the corresponding second adjusting screw 32 is rotated to adjust the height position of the heating unit 2.

[0030] Example 2: like Figures 1 to 8 As shown, this embodiment is based on embodiment 1, the difference being that in this embodiment: The temperature monitoring assembly includes a mounting rod 41 and several temperature sensors 42. The mounting rod 41 is vertically arranged, and the temperature sensors 42 are evenly distributed along the axial direction of the mounting rod 41. For the temperature monitoring assembly inside the upper furnace shell 11, its mounting rod 41 is rotatably mounted on the bearing ring 14 and its upper end passes through the top cover 15 and is located inside the top cover 17. For the temperature monitoring assembly inside the lower furnace shell 12, its mounting rod 41 is rotatably mounted on the bottom plate 16 and its lower end passes through the bottom plate 16 and is located inside the bottom cover 18.

[0031] It should be understood that the rotating mounting rod 41 has a locking mechanism for unlocking the mounting rod 41 to allow it to rotate and for locking the mounting rod 41 to prevent it from rotating. This locking mechanism, for example, involves threads on the section of the mounting rod 41 located inside the top cover 17 near the top cover 15, with a nut threaded onto it. When it is necessary to rotate the mounting rod 41, the nut is loosened, allowing the mounting rod 41 to rotate; when it is necessary to lock the mounting rod 41, the nut is tightened, preventing the mounting rod 41 from rotating (taking the mounting rod 41 inside the upper furnace shell 11 as an example; the locking mechanism for the mounting rod 41 inside the lower furnace shell 12 is similar and will not be described further). The temperature sensor 42 can be a commercially available thermocouple, which will not be described further here. To avoid interference with the temperature monitoring components when the height positions of the heating units 2 are adjusted, preferably, the vertical projection of the mounting rod 41 is located between the vertical projection of the heating unit 2 and the vertical projection of the pressure reactor 19.

[0032] Accordingly, this embodiment provides a heating device for a pressure reactor. By rotating the mounting rod 41, when hoisting the pressure reactor 19, rotating the mounting rod 41 causes each temperature sensor 42 to deviate from the target position of the pressure reactor 19 (e.g., ...). Figure 7 , Figure 8 As shown), this avoids the pressure vessel 19 from touching and damaging the temperature sensor 42 during the hoisting process. After the pressure vessel 19 is installed in place, rotating the mounting rod 41 allows the temperature sensor 42 to be attached to the outer peripheral wall of the pressure vessel 19 (as shown). Figure 8 For example, rotate the mounting rod 41 counterclockwise so that the temperature sensor 42 is attached to the outer peripheral wall of the pressure reactor 19, and then lock the mounting rod 41 to prevent it from loosening, thereby enabling more accurate monitoring of the temperature of the pressure reactor 19.

[0033] Example 3: like Figures 6 to 8 As shown, this embodiment is based on embodiment 1, the difference being that in this embodiment: The heating unit 2 includes a mounting ring 21 and a heating wire 22; The mounting ring 21 is used to slide with the upper furnace shell 11 or the lower furnace shell 12, and is used to thread with the first adjusting screw 31 or the second adjusting screw 32; Multiple fixing members 23 are evenly distributed in a spiral array along the axial direction on the inner circumferential surface of the mounting ring 21. The heating wire 22 passes through each of the fixing members 23 one by one, and the projections of the two ends of the heating wire 22 on the end face of the mounting ring 21 coincide (e.g., Figure 6 As shown, multiple fasteners 23 are all on the same helical line, which is located on the inner circumferential surface of the mounting ring 21. The spacing between any two adjacent fasteners 23 along the helical direction of the helical line is equal. To facilitate the demonstration of the arrangement of the fasteners 23, Figure 6 The dimensions of heating unit 2 are exaggerated in the axial direction.

[0034] Preferably, the fixing member 23 is made of an insulating and high-temperature resistant material, such as ceramic. This ensures that the heating wire 22 is securely installed and does not short-circuit with other components.

[0035] More preferably, a through hole is provided on the fixing member 23 along the direction of the array of fixing members 23, and a slot is provided above the fixing member 23, the slot connecting to the through hole. This allows for easy disassembly and replacement of a heating wire 22 if it is damaged.

[0036] It should be understood that both ends of the heating wire 22 are connected to the same fastener 23 (and the lowest fastener 23). This fastener 23 is adapted to differ in height from other fasteners 23. Specifically, this fastener 23 is taller and has two through holes of different heights in the vertical direction for connecting the beginning and end of the heating wire 22.

[0037] Accordingly, the heating device for a pressure reactor provided in this embodiment ensures that the starting and ending positions of the heating wire 22 in the heating unit 2 will not become shorter or longer due to the connection of the power supply (if the fixing member 23 is installed in a circumferential array, the two ends of the heating wire 22 cannot be directly closed, and there will be gaps, thus forming a relative cold zone).

[0038] More preferably, the cross-sectional area of ​​the heating wire 22 section between two adjacent fixing members 23 satisfies: , in, A For any point on this heating wire section P Cross-sectional area at the location, A 0 This is the cross-sectional area at the midpoint of the heating wire section. R This refers to the distance between the heating wire at the fixing point and the axis of the mounting ring. n For the number of fasteners, αThe coefficient is 1.5 < α <2, x For this point P Distance to the midpoint r The outer diameter is the pressure vessel to be heated.

[0039] The heating wire 22 is installed through various fixing members 23. The projection of the installed heating wire 22 onto the end face of the mounting ring 21 is essentially a regular polygon. Obviously, the more fixing members 23 there are, the closer this regular polygon is to a circle (correspondingly, the heating effect on the inner pressure reactor 19 is more uniform in the circumferential direction); however, too many fixing members 23 will greatly hinder the transfer of heat from the heating wire 22 to the pressure reactor 19, thereby reducing the heating efficiency; preferably, the number of fixing members 23 is 8 to 12.

[0040] Accordingly, this embodiment provides a heating device for a pressure reactor. To ensure a more uniform heating effect of the heating wire 22, whose projection on the end face of the mounting ring 21 is a regular polygon, on the pressure reactor 19 in the circumferential direction, the cross-sectional area of ​​the heating wire 22 is changed. This allows the heating power of the section of the heating wire 22 between two adjacent fixing members 23 to gradually increase from the midpoint to the fixing member 23. This compensates for the attenuation of radiation intensity caused by the greater distance of the heating wire 22 from the fixing member 23 to the pressure reactor 19 (the pressure reactor 19 is mainly heated by thermal radiation in the furnace), thereby achieving uniform heating of the pressure reactor 19 in the circumferential direction. Correspondingly, the greater the difference between the distance from the heating wire 22 at the fixing member 23 to the pressure reactor 19 and the distance from the heating wire 22 at the midpoint to the pressure reactor 19, the larger the value of the coefficient α.

[0041] Example 4: This embodiment provides a heating method for a pressure reactor. Based on the aforementioned heating device, the heating method includes: The pressure reactor 19 is hoisted and installed inside the furnace body, so that the pressure reactor 19 is coaxial with the lower furnace shell 12; The heating units 2 are controlled to heat the reactor inside the upper furnace shell 11 to reach and maintain a first preset temperature, and the reactor inside the lower furnace shell 12 to reach and maintain a second preset temperature; wherein the first preset temperature is lower than the second preset temperature. During the heating process of each heating unit 2, the heating power of at least one heating unit 2 at the bottom inside the upper furnace shell 11 is controlled to be lower than the heating power of other heating units 2 inside the upper furnace shell 11; the heating power of at least one heating unit 2 at the top inside the lower furnace shell 12 is controlled to be higher than the heating power of other heating units 2 inside the lower furnace shell 12.

[0042] Preferably, the heating power of the lowermost heating unit 2 inside the upper furnace shell 11 is 95% to 98% of the heating power of the other heating units 2, and the heating power of the uppermost heating unit 2 inside the lower furnace shell 12 is 102% to 105% of the heating power of the other heating units 2.

[0043] Accordingly, this embodiment provides a heating method for a pressure reactor. By reducing the heating power of at least one heating unit 2 at the lowest inner side of the upper furnace shell 11, the heat redundancy caused by the heat transferred from the heating unit 2 inside the lower furnace shell 12 (mainly the heat transferred from the float of the pressure reactor 19) is buffered, thus preventing the temperature of the lower inner side of the upper furnace shell 11 from becoming too high. Similarly, by increasing the heating power of at least one heating unit 2 at the highest inner side of the lower furnace shell 12, the heat loss caused by the heat transferred from the inner side of the lower furnace shell 12 to the upper furnace shell 11 is compensated, thus preventing the temperature of the upper inner side of the lower furnace shell 12 from becoming too low. This narrows the transition area between the region of the first preset temperature inside the upper furnace shell 11 and the region of the second preset temperature inside the lower furnace shell 12, which is beneficial for uniformly heating the upper and lower halves of the pressure reactor 19 at the first and second preset temperatures, respectively.

[0044] Preferably, the temperature monitoring component is controlled to continuously monitor the measured temperature at multiple monitoring points on the outer wall of the pressure reactor 19; If the measured temperature at any monitoring point deviates from the target temperature by more than 10°C, adjust the power of at least one heating unit 2 near that monitoring point; including: If the measured temperature is greater than the target temperature, the power of at least one heating unit 2 at that location is reduced; if the measured temperature is less than the target temperature, the power of at least one heating unit 2 at that location is increased.

[0045] Accordingly, this embodiment provides a heating method for a pressure reactor. By real-time monitoring of the measured temperatures at multiple monitoring points inside the upper furnace shell 11 and the lower furnace shell 12, the heating power of the adjacent heating unit 2 can be adjusted in a timely manner when the temperature of a small segment in each height direction inside the upper furnace shell 11 and the lower furnace shell 12 is too high or too low. This ensures that the temperature of the small segment in each height direction is not too high or too low, which is beneficial to ensure that the upper furnace shell 11 and the lower furnace shell 12 heat the internal pressure reactor 19 at a first preset temperature and a second preset temperature, respectively.

[0046] More preferably, if any heating unit 2 is damaged during the heating process of each of the heating units 2, the height position of other heating units 2 located on the same inner side of the furnace shell as the damaged heating unit 2 is adjusted so that the other heating units 2 are evenly distributed in the vertical direction.

[0047] Specifically, for each heating unit 2 inside the upper furnace shell 11, the distance between the uppermost heating unit 2 and the supporting ring 14 is equal to the distance between the lowermost heating unit 2 and the heat insulation ring 13, which is equal to half the distance between two adjacent heating units 2. For each heating unit 2 inside the lower furnace shell 12, the distance between the uppermost heating unit 2 and the heat insulation ring 13 is equal to the distance between the lowermost heating unit 2 and the bottom plate 16, which is equal to half the distance between two adjacent heating units 2. The adjustment of the height position of other heating units 2 located on the same inner side of the furnace shell as the damaged heating unit 2 includes: By rotating the first adjusting screw 31 or the second adjusting screw 32 corresponding to the other heating units 2, the height position of each heating unit 2 is adjusted; the height adjustment amount of each heating unit 2 satisfies: , in, ΔH The height adjustment amount of the heating unit to be adjusted. j The serial number of the heating unit to be adjusted. H This refers to the inner cavity height of the furnace shell. N To adjust the number of front heating units, i This is the serial number of the damaged heating unit.

[0048] It should be understood that, for the upper furnace shell 11, the inner cavity height of the furnace shell refers to the distance between the bearing ring 14 and the heat insulation ring 13; for the lower furnace shell 12, the inner cavity height of the furnace shell refers to the distance between the heat insulation ring 13 and the bottom plate 16; the serial number refers to the number obtained by numbering the heating unit 2 at one end of the vertical direction in the upper furnace shell 11 or the lower furnace shell 12 as 1, and then sequentially increasing the number of other heating units 2 by 1 towards the other end; for the calculation result of ΔH, its absolute value represents the distance that the heating unit 2 needs to be adjusted in the vertical direction. A positive result means that the heating unit 2 needs to be adjusted to move in the direction of increasing serial number, and a negative result means that the heating unit 2 needs to be adjusted to move in the direction of decreasing serial number. Taking the multiple heating units 2 inside the lower furnace shell 12 as an example, the uppermost heating unit 2 on its inner side is numbered 1, and the other heating units 2 are numbered 2, 3, 4... from top to bottom. Then, if the heating unit 2 with the number i on the inner side of the lower furnace shell 12 is damaged, the height adjustment amount of the heating unit 2 with the number j is obtained according to the above method. If the result is positive, the position of the heating unit 2 is adjusted downward; if the result is negative, the position of the heating unit 2 is adjusted upward.

[0049] Accordingly, this embodiment provides a heating method for a pressure reactor. By setting the distance between the uppermost heating unit 2 and the support ring 14 to be equal to the distance between the lowermost heating unit 2 and the insulation ring 13 to be equal to half the distance between two adjacent heating units 2, the temperature at both ends of the inner cavity of the furnace shell is prevented from being too low or too high (the lower furnace shell 12 is similar and will not be described again). The above formula accurately determines the height that other heating units 2 need to be adjusted if any heating unit 2 is damaged during the heating process, thus facilitating the adjustment of the heating units 2 that still have intact heating functions to be evenly distributed in the vertical direction. It is worth noting that by using the first adjusting screw 31 or the second adjusting screw 32 to adjust the height of each heating unit 2, the height position of the heating unit 2 can be reliably adjusted during the heating process (without involving electrical drive, and can better adapt to the high temperature environment inside the furnace). Obviously, the pitch and number of threads of the first adjusting screw 31 and the second adjusting screw 32 are known (i.e., the distance that the heating unit 2 moves with each rotation is known). According to the height adjustment amount obtained from the above formula, the angle of rotation of the first adjusting screw 31 or the second adjusting screw 32 can be determined, which facilitates the operation of adjusting the height position and has high adjustment accuracy.

[0050] It should be understood that the circuit connections are not shown in this application. The circuit connections and high-temperature protection of the circuit can be carried out in accordance with the prior art. However, it is necessary to ensure that each heating unit 2 can control the current independently and that the failure of any heating unit 2 does not affect the normal operation of other heating units 2.

[0051] It should be understood that, unless otherwise specified, in this application, the terms "rotational connection" and "rotational installation" refer to two things that can only rotate relative to each other, such as the rotational connection of a hole and a shaft, which can restrict axial relative movement by setting a shoulder on the shaft and a limiting groove in the hole; the term "sliding connection" refers to two things that can only slide relative to each other, such as dovetail grooves, T-slots and other structures.

[0052] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A heating device for a pressure reactor, characterized in that, include: The furnace body includes an upper furnace shell (11), a lower furnace shell (12), and a heat insulation ring (13) coaxially mounted; a bearing ring (14) is fixedly installed on the upper part of the upper furnace shell (11), a top cover (15) is detachably installed on the top of the upper furnace shell (11), and a bottom plate (16) is fixedly installed on the bottom of the lower furnace shell (12); the heat insulation ring (13) is sandwiched between the bottom of the upper furnace shell (11) and the top of the lower furnace shell (12); Heating unit (2) is provided in a vertical direction on both the inner side of the upper furnace shell (11) and the inner side of the lower furnace shell (12). The first adjusting screw (31) is vertically arranged on the inner side of the upper furnace shell (11). Each first adjusting screw (31) is threadedly connected to the heating unit (2) on the inner side of the upper furnace shell (11) in a one-to-one correspondence. Each first adjusting screw (31) is rotatably connected to the bearing ring (14). The second adjusting screw (32) is vertically arranged on the inner side of the lower furnace shell (12). Each second adjusting screw (32) is threadedly connected to a heating unit (2) on the inner side of the lower furnace shell (12) in a one-to-one correspondence, and each second adjusting screw (32) is rotatably connected to the bottom plate (16); and, The temperature monitoring components are installed on the inner side of both the upper furnace shell (11) and the lower furnace shell (12).

2. The heating device according to claim 1, characterized in that, A top cover (17) is detachably installed above the top cover (15), and a bottom cover (18) is detachably installed below the bottom plate (16). The upper part of the first adjusting screw (31) passes through the top cover (15) and is located inside the top cover (17), and the lower part of the second adjusting screw (32) passes through the bottom plate (16) and is located inside the bottom cover (18).

3. The heating device according to claim 2, characterized in that, The temperature monitoring assembly includes a mounting rod (41) and a plurality of temperature sensors (42). The mounting rod (41) is vertically arranged, and each of the temperature sensors (42) is evenly distributed along the axial direction of the mounting rod (41). For the temperature monitoring component inside the upper furnace shell (11), its mounting rod (41) is rotatably mounted on the bearing ring (14) and its upper end passes through the top cover (15) and is located inside the top cover (17); for the temperature monitoring component inside the lower furnace shell (12), its mounting rod (41) is rotatably mounted on the bottom plate (16) and its lower end passes through the bottom plate (16) and is located inside the bottom cover (18).

4. The heating device according to claim 1, characterized in that, The heating unit (2) includes a mounting ring (21) and a heating wire (22); The mounting ring (21) is used to slide with the upper furnace shell (11) or the lower furnace shell (12), and is used to thread with the first adjusting screw (31) or the second adjusting screw (32); Multiple fasteners (23) are evenly distributed in a spiral array along the axial direction on the inner circumferential surface of the mounting ring (21). The heating wire (22) passes through each of the fasteners (23) one by one, and the projections of the two ends of the heating wire (22) on the end face of the mounting ring (21) coincide.

5. The heating device according to claim 4, characterized in that, The cross-sectional area of ​​the heating wire (22) section between two adjacent fixing members (23) satisfies: ， in, A For any point on this heating wire section P Cross-sectional area at the location, A 0 This is the cross-sectional area at the midpoint of the heating wire section. R This refers to the distance between the heating wire at the fixing point and the axis of the mounting ring. n For the number of fasteners, α The coefficient is 1.5 < α <2, x For this point P Distance to the midpoint r The outer diameter is the pressure vessel to be heated.

6. The heating device according to claim 4, characterized in that, The fastener (23) is made of ceramic material; through holes are provided on the fastener (23) along the direction of the array of fasteners (23), and a slot is provided above the fastener (23), the slot being connected to the through holes.

7. A heating method for a pressure reactor, based on the heating device according to any one of claims 1 to 6, characterized in that, include: The pressure reactor (19) is hoisted and installed inside the furnace body, so that the pressure reactor (19) is coaxial with the lower furnace shell (12); The heating units (2) are controlled to heat the reactor inside the upper furnace shell (11) to reach and maintain a first preset temperature, and the reactor inside the lower furnace shell (12) to reach and maintain a second preset temperature; wherein the first preset temperature is lower than the second preset temperature. During the heating process of each heating unit (2), the heating power of at least one heating unit (2) at the bottom inside the upper furnace shell (11) is controlled to be lower than the heating power of other heating units (2) inside the upper furnace shell (11); the heating power of at least one heating unit (2) at the top inside the lower furnace shell (12) is controlled to be higher than the heating power of other heating units (2) inside the lower furnace shell (12).

8. The heating method according to claim 7, characterized in that, The temperature monitoring component is controlled to continuously monitor the measured temperature at multiple monitoring points on the outer wall of the pressure reactor (19); If the measured temperature at any monitoring point deviates from the target temperature by more than 10°C, adjust the power of at least one heating unit (2) near that monitoring point; including: If the measured temperature is greater than the target temperature, the power of at least one heating unit (2) at that location is reduced; if the measured temperature is less than the target temperature, the power of at least one heating unit (2) at that location is increased.

9. The heating method according to claim 7, characterized in that, If any heating unit (2) is damaged during the heating process of each of the heating units (2), the height position of other heating units (2) located on the same inner side of the furnace shell as the damaged heating unit (2) is adjusted so that the other heating units (2) are evenly distributed in the vertical direction.

10. The heating method according to claim 9, characterized in that, For each heating unit (2) inside the upper furnace shell (11), the distance between the uppermost heating unit (2) and the supporting ring (14) is equal to the distance between the lowermost heating unit (2) and the heat insulation ring (13) is equal to half the distance between two adjacent heating units (2); For each heating unit (2) inside the lower furnace shell (12), the distance between the uppermost heating unit (2) and the heat insulation ring (13) is equal to the distance between the lowermost heating unit (2) and the bottom plate (16) is equal to half the distance between two adjacent heating units (2); The adjustment of the height position of other heating units (2) located inside the same furnace shell as the damaged heating unit (2) includes: By rotating the first adjusting screw (31) or the second adjusting screw (32) corresponding to the other heating units (2), the height position of each heating unit (2) is adjusted; the height adjustment amount of each heating unit (2) satisfies: ， in, ΔH The height adjustment amount of the heating unit to be adjusted. j The serial number of the heating unit to be adjusted. H This refers to the inner cavity height of the furnace shell. N To adjust the number of front heating units, i This is the serial number of the damaged heating unit.

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