A heating device and method for a pressure reactor

Abstract

The present application relates to heating furnace technical field, specifically to a kind of heating device and method for pressure reaction kettle.The heating device includes furnace body, furnace body is on furnace shell, lower furnace shell and heat insulation ring;Ring is installed on the upper furnace shell upper portion, top cover is installed on the top of upper furnace shell, bottom plate is installed on the bottom of lower furnace shell;Heat insulation ring is clamped between upper furnace shell and lower furnace shell;Multiple heating units are provided in the inner side of upper furnace shell and lower furnace shell;First adjusting screw is screw-connected with heating unit one-to-one in the inner side of upper furnace shell;Second adjusting screw is screw-connected with heating unit one-to-one in the inner side of lower furnace shell;Temperature monitoring component is installed in the inner side of upper furnace shell and lower furnace shell.The heating device can be heated to pressure reaction kettle in axial and circumferential direction evenly;In the case where a certain heating unit is suddenly damaged, the height position of other heating units is adjusted to maintain uniform axial heating effect.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of heating furnace, in particular to a heating device and method for a pressure reaction kettle. BACKGROUND

[0002] With the development of science and technology, semiconductor materials are closely related to people's life. As a representative of the third generation of semiconductor materials, gallium nitride (GaN) has the advantages of wide band gap, small dielectric coefficient, high electron mobility, high thermal conductivity and radiation resistance, and is widely used in optoelectronic devices and microelectronic fields.

[0003] At present, the main methods for preparing GaN single crystal materials are hydride vapor phase epitaxy, ammonia thermal method and flux method. Among them, the ammonia thermal method for preparing GaN single crystal materials has the advantages of high crystallization quality, easy to carry out large-scale production and low cost, and is expected to become the main method of commercial production. The principle of preparing GaN single crystal material by ammonia thermal method is: by controlling the temperature, the pressure reaction kettle is divided into two regions with different temperatures, one is the dissolution zone and the other is the growth zone. The convection generated by the temperature difference between the dissolution zone and the growth zone transports the dissolved Ga source (polycrystalline GaN or Ga) to the growth zone, so that the region appears supersaturation, and then GaN is crystallized and grown.

[0004] Correspondingly, in order to facilitate the segmented control of the furnace temperature, it is usually necessary to set heating units in the dissolution zone and the growth zone respectively and adjust the heating temperature respectively, so as to form the required temperature difference. For example, a segmented uniform heating furnace disclosed in Chinese patent CN202311518127.8 can better realize the separate adjustment of the temperature of the dissolution zone and the growth zone by setting multiple separately controlled heating units. However, for this heating furnace, if one of the heating units suddenly fails and cannot heat, a local cold zone will be formed near the heating unit, which will change the temperature field in the kettle and disturb the solute migration driven by the temperature difference, so that the GaN growth rate is locally reduced or stopped, thereby causing the increase of crystal defects, the increase of dislocation density, and even inducing non-directional nucleation. For this situation, if the furnace is stopped to replace the heating unit, the solute migration is interrupted when the furnace is stopped, and the local growth on the crystal surface is not completed, which will freeze the lattice defects, vacancies or impurities, resulting in interface roughness or growth stripes. After heating again after repair, the crystal will continue to grow on the "old interface", but the roughness and defect density of the interface are usually high, which easily leads to poor combination of new and old crystal regions, affecting the integrity of the single crystal; if the power of the adjacent heating unit is gradually increased to compensate, the temperature of the region near the adjacent heating unit may rise, which may cause thermal stress concentration, resulting in cracks, dislocations and other defects in the GaN crystal. SUMMARY

[0005] The application aims to provide a heating device and method for a pressure reactor, which can uniformly heat the pressure reactor in axial and circumferential directions; in the case of sudden damage of a heating unit and failure to continue heating, the remaining heating units can still be uniformly distributed along the vertical direction through adjustment of the height positions of other heating units, thereby ensuring longitudinal uniform heating effect and providing a still uniform heating area.

[0006] The application provides a heating device for a pressure reactor, which comprises a furnace body, the furnace body comprises coaxially installed upper furnace shell, lower furnace shell and heat insulation ring; a bearing ring is fixedly installed on the upper part of the upper furnace shell, a top cover is detachably installed on the top of the upper furnace shell, and a bottom plate is fixedly installed on the bottom of the lower furnace shell; the heat insulation ring is clamped between the bottom of the upper furnace shell and the top of the lower furnace shell; a plurality of heating units are slidably arranged in the vertical direction on the inner side of the upper furnace shell and the inner side of the lower furnace shell; a plurality of first adjusting screws are vertically arranged on the inner side of the upper furnace shell, each first adjusting screw is threadedly connected with a heating unit on the inner side of the upper furnace shell in a one-to-one correspondence, and each first adjusting screw is rotationally connected with the bearing ring; a plurality of second adjusting screws are vertically arranged on the inner side of the lower furnace shell, each second adjusting screw is threadedly connected with a heating unit on the inner side of the lower furnace shell in a one-to-one correspondence, and each second adjusting screw is rotationally connected with the bottom plate; and a temperature monitoring assembly is installed on the inner side of the upper furnace shell and the inner side of the lower furnace shell.

[0007] Further, 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 penetrates through the top cover and is located on the inner side of the top cover, and the lower part of the second adjusting screw penetrates through the bottom plate and is located on the inner side of the bottom cover.

[0008] Further, the temperature monitoring assembly comprises a mounting rod and a plurality of temperature sensors, the mounting rod is vertically arranged, and each temperature sensor is uniformly distributed along the axial direction of the mounting rod; for the temperature monitoring assembly on the inner side of the upper furnace shell, the mounting rod is rotationally installed on the bearing ring and the upper end penetrates through the top cover and is located on the inner side of the top cover; for the temperature monitoring assembly on the inner side of the lower furnace shell, the mounting rod is rotationally installed on the bottom plate and the lower end penetrates through the bottom plate and is located on the inner side of the bottom cover.

[0009] Further, the heating unit comprises a mounting ring and an electric heating wire; the mounting ring is used for sliding connection with the upper furnace shell or the lower furnace shell, and is used for threadedly connecting with the first adjusting screw or the second adjusting screw; a plurality of fixing members are uniformly distributed on the inner circumferential surface of the mounting ring in axial spiral array, the electric heating wire penetrates through each fixing member one by one, and the projections of the two ends of the electric heating wire on the end surface of the mounting ring are coincident.

[0010] Further, the cross-sectional area of the heating wire section between two adjacent fixing members satisfies:

[0011] ,

[0012] wherein, A A is the cross-sectional area of any point on the heating wire section, P A0 is the cross-sectional area of the midpoint of the heating wire section, A 0 A0 is the cross-sectional area of the midpoint of the heating wire section, R L is the distance between the heating wire and the axis of the mounting ring at the fixing member, n N is the number of fixing members, α K is a coefficient and 1.5 < K < 2, α x L is the distance between the heating wire and the axis of the mounting ring at the fixing member, P r D is the outer diameter of the pressure reactor to be heated.

[0013] Further, the fixing member is made of ceramic material; a through hole is formed on the fixing member along the direction of the array of fixing members; and a notch is formed on the fixing member and communicates with the through hole.

[0014] Another aspect of the present application provides a heating method for a pressure reactor, based on the heating device described above, the heating method comprising: hoisting and installing the pressure reactor into the furnace body so that the pressure reactor is coaxial with the lower furnace shell; controlling each heating unit to heat so 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 of each heating unit, the heating power of at least one heating unit at the lowermost part of the inside of the upper furnace shell is lower than that of other heating units inside the upper furnace shell; and the heating power of at least one heating unit at the uppermost part of the inside of the lower furnace shell is higher than that of other heating units inside the lower furnace shell.

[0015] Further, the temperature monitoring assembly continuously monitors the measured temperatures of multiple monitoring points on the outer wall of the pressure reactor; in the case that the measured temperature of any monitoring point deviates from the target temperature by more than 10℃, the power of at least one heating unit adjacent to the monitoring point is adjusted; including: in the case that the measured temperature is greater than the target temperature, the power of at least one heating unit at the point is reduced; and in the case that the measured temperature is less than the target temperature, the power of at least one heating unit at the point is increased.

[0016] ​​Further, in case any of the heating units is damaged during the heating process of the heating units, the height positions of the other heating units inside the same furnace shell as the damaged heating unit are adjusted so that the other heating units are uniformly distributed in the vertical direction.

[0017] Further, for each heating unit inside the upper furnace shell, the distance between the uppermost heating unit and the bearing ring is equal to the distance between the lowermost heating unit and the heat insulation ring, which is equal to half of 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 heat insulation ring is equal to the distance between the lowermost heating unit and the bottom plate, which is equal to half of the distance between two adjacent heating units; the adjustment of the height positions of the other heating units inside the same furnace shell as the damaged heating unit includes: adjusting the height positions of the heating units by rotating the first adjusting screw or the second adjusting screw corresponding to the other heating units; the height adjustment amount of each heating unit satisfies:

[0018] ,

[0019] wherein, ΔH is the height adjustment amount of the heating unit to be adjusted, j is the serial number of the heating unit to be adjusted, H is the height of the inner cavity of the furnace shell, N is the number of heating units before adjustment, i is the serial number of the damaged heating unit.

[0020] Compared with the prior art, the present application has the following advantages and beneficial effects:

[0021] 1. The heating device and method for the pressure reaction kettle provided by the present application, by slidingly arranging the heating units inside the upper furnace shell and the lower furnace shell in the vertical direction and determining the height positions of the heating units by the first adjusting screws and the second adjusting screws, the uniform distribution of the heating units in the vertical direction is realized, and the pressure reaction kettle inside is heated uniformly in the axial direction; in addition, in case any of the heating units is damaged suddenly and cannot be heated during the heating process of the pressure reaction kettle, by rotating the corresponding first adjusting screw or second adjusting screw, the height positions of the other heating units inside the furnace shell corresponding to the damaged heating unit are adjusted, and the other heating units are still uniformly distributed in the vertical direction; for the preparation of GaN single crystal material based on the ammonia thermal method by the pressure reaction kettle, in case a heating unit in the corresponding furnace shell of the dissolution zone or the growth zone is damaged and cannot be heated, the dissolution zone and the growth zone can still be provided with uniform heating temperature field, the crystal is kept to grow stably, and the influence of the situation on the quality of the single crystal material generated in the kettle can be greatly reduced;

[0022] 2. The heating device and method for a pressure reaction kettle provided by the application, by changing the cross-sectional area of the heating wire, the heating power of the heating wire section between two adjacent fixed parts gradually increases from the midpoint position to the fixed part position, thereby compensating for the radiation intensity attenuation of the heating wire near the fixed part due to the greater distance from the pressure reaction kettle, and the pressure reaction kettle can be uniformly heated in the circumferential direction;

[0023] 3. The heating device and method for a pressure reaction kettle provided by the application, by setting the distance between the uppermost heating unit and the bearing ring inside the upper furnace shell equal to the distance between the lowermost heating unit and the heat insulation ring, and equal to half the distance between the two adjacent heating units, the temperature at both ends of the inner cavity of the furnace shell can not be too low or too high; in the case of damage to any heating unit during heating, the height adjustment of other heating units can be accurately known, and then the heating units with intact functions can be adjusted to be uniformly distributed in the vertical direction; it is worth noting that the height of each heating unit is adjusted by the first adjusting screw or the second adjusting screw, which does not involve electrical driving, can better adapt to the high temperature environment in the furnace, and then the height position of the heating unit can be reliably adjusted during the heating process. BRIEF DESCRIPTION OF DRAWINGS

[0024] The accompanying drawings, which are included to provide a further understanding of the embodiments of the application and are incorporated in and constitute a part of this application, illustrate embodiments of the application and together with the description serve to explain the principles of the application. In the drawings:

[0025] Figure 1 The perspective structural schematic view of the heating device for a pressure reaction kettle according to the embodiments of the application is shown;

[0026] Figure 2 The longitudinal sectional view of the heating device for a pressure reaction kettle according to the embodiments of the application is shown; Figure 1 The partial enlarged view of the A area is shown;

[0027] Figure 3 The longitudinal sectional view of the heating device for a pressure reaction kettle according to the embodiments of the application is shown;

[0028] Figure 4 The partial enlarged view of the B area is shown; Figure 3 The perspective structural schematic view of the heating device for a pressure reaction kettle according to the embodiments of the application is shown;

[0029] Figure 5 The other longitudinal sectional view of the heating device for a pressure reaction kettle according to the embodiments of the application is shown;

[0030] Figure 6 The perspective structural schematic view of the heating unit according to the embodiments of the application is shown;

[0031] Figure 7 The scene schematic view of the heating unit heating the pressure reaction kettle according to the embodiments of the application is shown;

[0032] Figure 8 To according to Figure 3 A local enlarged view of the C region is drawn.

[0033] Markings in the drawings and corresponding names of parts:

[0034] 11 - upper furnace shell; 12 - lower furnace shell; 13 - heat insulation ring; 14 - bearing 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 part; 31 - first adjusting screw; 32 - second adjusting screw; 41 - mounting rod; 42 - temperature sensor. DETAILED DESCRIPTION

[0035] In order to make the purpose, technical scheme and advantages of the present application clearer, further detailed description will be given below in combination with examples and drawings. The illustrative embodiments of the present application and their descriptions are only used to explain the present application and do not limit the present application. It should be noted that the present application has been in the actual research and development stage.

[0036] Gallium nitride (GaN) as a representative of the third generation of semiconductor materials, has the advantages of wide band gap, small dielectric coefficient, high electron mobility, high thermal conductivity and radiation resistance, and is widely used in optoelectronic devices and microelectronic fields. At present, the main methods for preparing GaN single crystal materials are hydride vapor phase epitaxy, ammonia thermal method and flux method. Among them, the ammonia thermal method for preparing GaN single crystal material is expected to become the main method for commercial production due to its high crystalline quality, easy scale production and low cost. The principle of preparing GaN single crystal material by ammonia thermal method is: by controlling the temperature, the pressure reactor is divided into two regions with different temperatures, one is the dissolution zone and the other is the growth zone. The convection generated by the temperature difference between the dissolution zone and the growth zone transports the dissolved Ga source (polycrystalline GaN or Ga) to the growth zone, so that the region appears supersaturation, and then GaN is crystallized and grown.

[0037] Accordingly, when preparing a GaN single crystal material by an ammonia thermal method, in order to facilitate segmented control of the furnace temperature, it is usually necessary to respectively set heating units in the dissolution zone and the growth zone and respectively regulate the heating temperature, thereby forming the required temperature difference. For example, a segmented uniform heating furnace disclosed in Chinese Patent CN202311518127.8 can better achieve the respective regulation of the temperature of the dissolution zone and the growth zone by setting multiple separately controlled heating units. However, for this heating furnace, if a certain heating unit suddenly fails to heat, a local cold zone will be formed near the heating unit, causing the temperature field in the kettle to change and thereby disturbing the solute migration under the driving of the temperature difference, so that the GaN growth rate locally decreases or stops, thereby causing the crystal defects to increase, the dislocation density to rise, and even inducing non-directional nucleation.

[0038] For this case, if the heating unit is replaced after the furnace is stopped, the solute migration is interrupted when the furnace is stopped, and the local growth on the crystal surface is not completed, which will freeze the crystal lattice defects, vacancies or impurities, resulting in interface roughness or growth stripes. After subsequent repair and heating, the crystal will continue to grow on the "old interface", but the interface roughness and defect density are usually high, which easily leads to poor combination of new and old crystal regions, affecting the integrity of the single crystal; if the power of the adjacent heating unit is gradually increased to compensate, the temperature rise in the region near the adjacent heating unit may cause thermal stress concentration, resulting in cracks, dislocations and other defects in the GaN crystal, and also disturb the original temperature field distribution in the pressure reaction kettle, disturbing the Ga source movement driven by the temperature gradient.

[0039] Therefore, the present application provides a heating device and method for a pressure reaction kettle, which can uniformly heat the pressure reaction kettle in the axial and circumferential directions. Especially for the case of "sudden failure of a certain heating unit to heat", the remaining heating units can still be uniformly distributed in the vertical direction by adjusting the height positions of the other heating units, thereby maintaining the uniform axial heating effect and being conducive to maintaining the original temperature field distribution in the pressure reaction kettle.

[0040] Embodiment 1:

[0041] As shown in Figures 1 to 5 , the present embodiment provides a heating device for a pressure reaction kettle, which comprises:

[0042] a furnace body, the furnace body comprising an upper furnace shell 11, a lower furnace shell 12 and a heat insulation ring 13 which are coaxially installed; a bearing ring 14 is fixedly installed on the upper portion 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 clamped between the bottom of the upper furnace shell 11 and the top of the lower furnace shell 12;

[0043] A plurality of heating units 2 are slidably arranged in the vertical direction inside the upper furnace shell 11 and the lower furnace shell 12;

[0044] A plurality of first adjusting screws 31 are vertically arranged inside the upper furnace shell 11, each of the first adjusting screws 31 is threadedly connected with a heating unit 2 inside the upper furnace shell 11 in a one-to-one correspondence, and each of the first adjusting screws 31 is rotationally connected with the bearing ring 14;

[0045] A plurality of second adjusting screws 32 are vertically arranged inside the lower furnace shell 12, each of the second adjusting screws 32 is threadedly connected with a heating unit 2 inside the lower furnace shell 12 in a one-to-one correspondence, and each of the second adjusting screws 32 is rotationally connected with the bottom plate 16; and

[0046] A temperature monitoring assembly is arranged inside the upper furnace shell 11 and the lower furnace shell 12.

[0047] In a specific implementation of the embodiment, the pressure reactor 19 to be heated is in a cylindrical shape, and the upper furnace shell 11 and the lower furnace shell 12 are both in a circular pipe shape (as shown in Figure 1 In order to facilitate the display of the internal structure of the heating device, Figure 1It should be understood that, in order to reduce heat dissipation to the outside, in the present embodiment, the upper furnace shell 11, the lower furnace shell 12, the heat insulation ring 13, the top cover 15, and the bottom plate 16 all have heat insulation performance, for example, from the inside to the outside (from the side close to the heating unit 2 to the side close to the outside), in turn including a high-temperature-resistant layer, a heat insulation layer, and a rigid support layer. The first adjusting screw 31 is threaded at the section inside the upper furnace shell 11, and the second adjusting screw 32 is threaded at the section inside the lower furnace shell 12, for threaded connection with the corresponding heating unit 2. Taking the inside of the upper furnace shell 11 as an example, the length of each threaded section of the first adjusting screw 31 is equal to the height of the inner cavity of the upper furnace shell 11 (it is meant that they are approximately equal, and 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 affecting the rotation of the first adjusting screw 31 due to abutting against the heat insulation ring 13, and also to avoid damaging the heat insulation ring 13 due to the rotation of the first adjusting screw 31 in the abutting state), and each first adjusting screw 31 is threaded only to the corresponding heating unit 2, and the other heating units 2 are provided with avoiding holes for avoiding 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 reaction kettle 19, so as to better insulate the heat conduction between the upper furnace shell 11 and the lower furnace shell 12 (it is meant to avoid temperature conduction from the gap between the heat insulation ring 13 and the pressure reaction kettle 19); the inner circumferential surface of the supporting ring 14 is adapted to the outer circumferential surface of the pressure reaction kettle 19, on the one hand, when the pressure reaction kettle 19 is hoisted into the furnace body, the inner circumferential surface of the supporting ring 14 is used to guide the pressure reaction kettle 19, so as to avoid the pressure reaction kettle 19 from touching and damaging the heating unit 2 and / or the heat insulation ring 13 during hoisting, and on the other hand, the supporting ring 14 is used to bear the weight of the pressure reaction kettle 19, so that the bottom of the pressure reaction kettle 19 is suspended (it is meant that there is a gap between the bottom of the pressure reaction kettle 19 and the bottom plate 16), so as to make the bottom of the pressure reaction kettle 19 be heated sufficiently.

[0048] 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.

[0049] 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;

[0050] 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.

[0051] 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.

[0052] 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.

[0053] Example 2:

[0054] like Figures 1 to 8 As shown, this embodiment is based on embodiment 1, the difference being that in this embodiment:

[0055] 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.

[0056] 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.

[0057] 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.

[0058] Example 3:

[0059] like Figures 6 to 8 As shown, this embodiment is based on embodiment 1, the difference being that in this embodiment:

[0060] The heating unit 2 includes a mounting ring 21 and a heating wire 22;

[0061] 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;

[0062] 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.

[0063] 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.

[0064] 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.

[0065] 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.

[0066] 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).

[0067] More preferably, the cross-sectional area of ​​the heating wire 22 section between two adjacent fixing members 23 satisfies:

[0068] ,

[0069] 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 the distance between the electric heating wire at the fixing member and the axis of the mounting ring, n the number of fixing members, α a coefficient and 1.5 < a < 2, α <2, x the distance from the point P to the midpoint, r the outer diameter of the pressure reactor to be heated.

[0070] The electric heating wire 22 is installed by the fixing members 23, and the projection of the installed electric heating wire 22 on the end face of the mounting ring 21 is essentially a regular polygon. Obviously, the more the number of fixing members 23, the closer the regular polygon is to a circle (correspondingly, the heating effect on the inner pressure reactor 19 is more uniform in the circumferential direction); but if the number of fixing members 23 is too large, it will greatly hinder the heat transfer from the electric heating wire 22 to the pressure reactor 19, thereby reducing the heating efficiency; preferably, the number of fixing members 23 is 8 to 12.

[0071] Accordingly, the heating device for the pressure reactor provided in the embodiment is used to make the heating effect of the electric heating wire 22, which is a regular polygon on the end face of the mounting ring 21, on the pressure reactor 19 more uniform in the circumferential direction, by changing the cross-sectional area of the electric heating wire 22, so that the heating power of the electric heating wire 22 section between two adjacent fixing members 23 gradually increases from the midpoint position to the fixing member 23 position, thereby making up for the radiation intensity attenuation of the electric heating wire 22 near the fixing member 23 due to the farther distance from the pressure reactor 19 (the pressure reactor 19 is mainly heated by heat radiation in the furnace), thereby achieving the purpose of uniform heating in the circumferential direction of the pressure reactor 19. Correspondingly, the greater the difference between the distance from the electric heating wire 22 at the fixing member 23 to the pressure reactor 19 and the distance from the electric heating wire 22 at the midpoint to the pressure reactor 19, the greater the value of the coefficient a.

[0072] Embodiment 4:

[0073] The heating method for the pressure reactor provided in the embodiment is based on the aforementioned heating device, and the heating method comprises:

[0074] Hoisting and installing the pressure reactor 19 inside the furnace body so that the pressure reactor 19 is coaxial with the lower furnace shell 12;

[0075] Controlling each heating unit 2 to heat so that the reactor temperature inside the upper furnace shell 11 reaches and maintains a first preset temperature, and so that the reactor temperature inside the lower furnace shell 12 reaches and maintains a second preset temperature; wherein the first preset temperature is lower than the second preset temperature;

[0076] During the heating process of each of the heating units 2, the heating power of the at least one heating unit 2 at the lowermost position inside the upper furnace shell 11 is controlled to be lower than the heating power of the other heating units 2 inside the upper furnace shell 11; and the heating power of the at least one heating unit 2 at the uppermost position inside the lower furnace shell 12 is controlled to be higher than the heating power of the other heating units 2 inside the lower furnace shell 12.

[0077] Preferably, the heating power of the at least one heating unit 2 at the lowermost position 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 at least one heating unit 2 at the uppermost position inside the lower furnace shell 12 is 102% to 105% of the heating power of the other heating units 2.

[0078] Accordingly, the heating method for the pressure reactor provided by the embodiment can buffer the heat redundancy caused by the heat transferred from the heating units 2 inside the lower furnace shell 12 (mainly the heat transferred by the floating body of the pressure reactor 19) to the heating units 2 inside the upper furnace shell 11, by adjusting the heating power of the at least one heating unit 2 at the lowermost position inside the upper furnace shell 11, so as to avoid the temperature of the lower part of the upper furnace shell 11 being too high; similarly, by adjusting the heating power of the at least one heating unit 2 at the uppermost position inside the lower furnace shell 12, the heat loss caused by the heat transferred from the lower furnace shell 12 to the upper furnace shell 11 can be compensated, so as to avoid the temperature of the upper part of the lower furnace shell 12 being too low. In this way, the transition area between the first preset temperature area inside the upper furnace shell 11 and the second preset temperature area inside the lower furnace shell 12 can be narrowed, which is beneficial to uniformly heating the upper half and the lower half of the pressure reactor 19 at the first preset temperature and the second preset temperature respectively.

[0079] Preferably, the temperature monitoring assembly is controlled to continuously monitor the measured temperatures of the plurality of monitoring points on the outer wall of the pressure reactor 19.

[0080] In the case that the measured temperature of any monitoring point deviates from the target temperature by more than 10℃, the power of at least one heating unit 2 adjacent to the monitoring point is adjusted; including:

[0081] In the case that the measured temperature is greater than the target temperature, the power of the at least one heating unit 2 is reduced; and in the case that the measured temperature is less than the target temperature, the power of the at least one heating unit 2 is increased.

[0082] Accordingly, the heating method for the pressure reactor provided by the embodiment can monitor the measured temperature of the multiple monitoring points inside the upper furnace shell 11 and the lower furnace shell 12 in real time, and then timely adjust the heating power of the adjacent heating units 2 when the temperature of the small section in each height direction of the upper furnace shell 11 and the lower furnace shell 12 is too high or too low, so as to ensure that the temperature of the small section in each height direction is not too high or too low, and to facilitate ensuring that the upper furnace shell 11 and the lower furnace shell 12 heat the internal pressure reactor 19 at the first preset temperature and the second preset temperature, respectively.

[0083] More preferably, in the case that any heating unit 2 is damaged during the heating process of each heating unit 2, the height positions of the other heating units 2 inside the same furnace shell as the damaged heating unit 2 are adjusted, so that the other heating units 2 are uniformly distributed along the vertical direction.

[0084] Specifically, for each heating unit 2 inside the upper furnace shell 11, the distance between the uppermost heating unit 2 and the bearing 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 the adjacent two heating units 2.

[0085] 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 the adjacent two heating units 2.

[0086] The adjustment of the height positions of the other heating units 2 inside the same furnace shell as the damaged heating unit 2 includes:

[0087] The height positions of each heating unit 2 are adjusted by rotating the first adjusting screw 31 or the second adjusting screw 32 corresponding to the other heating units 2, and the height adjustment amount of each heating unit 2 satisfies:

[0088] ,

[0089] wherein, ΔH is the height adjustment amount of the heating unit to be adjusted, j is the serial number of the heating unit to be adjusted, H is the height of the inner cavity of the furnace shell, N is the number of heating units before adjustment, i is the serial number of the damaged heating unit.

[0090] 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 supporting ring 14 and the heat insulation ring 13, and 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 of the heating unit 2 at one end in the vertical direction in the upper furnace shell 11 or the lower furnace shell 12, and the other heating units 2 are sequentially numbered by increasing 1 towards the other end; for the calculation result of ΔH, the absolute value represents the distance that the heating unit 2 needs to be adjusted in the vertical direction, and the positive result indicates that the heating unit 2 needs to be adjusted to move in the direction of increasing serial number, and the negative result indicates that the heating unit 2 needs to be adjusted to move in the direction of decreasing serial number. Taking the plurality of heating units 2 in the lower furnace shell 12 as an example, the uppermost heating unit 2 inside is numbered 1, and the other heating units 2 are sequentially numbered 2, 3, 4… from top to bottom, and then in the case that the heating unit 2 with serial number i inside the lower furnace shell 12 is damaged, the height adjustment amount of the heating unit 2 with serial number j is obtained according to the above method, if the result is positive, the position of the heating unit 2 is adjusted downward, and if the result is negative, the position of the heating unit 2 is adjusted upward.

[0091] Accordingly, the embodiment provides a heating method for a pressure reaction kettle, by setting each heating unit 2 inside the upper furnace shell 11 to have a distance between the uppermost heating unit 2 and the supporting ring 14 equal to a distance between the lowermost heating unit 2 and the heat insulation ring 13 equal to half the distance between two adjacent heating units 2, so that the temperature at both ends of the inner cavity of the furnace shell is not too low or too high (similar to the lower furnace shell 12, which will not be described again). Through the above formula, it can be accurately known that in the case that any heating unit 2 is damaged during heating, the height of each other heating unit 2 needs to be adjusted, and then the heating units 2 with intact heating functions are adjusted to be uniformly distributed in the vertical direction. It is worth noting that adjusting the height of each heating unit 2 by using the first adjusting screw 31 or the second adjusting screw 32 can reliably achieve the adjustment of the height position of the heating unit 2 during heating (not involving electrical driving, which can better adapt to the high-temperature environment in the furnace). Obviously, the pitch and the 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 per revolution is known), and the height adjustment amount obtained according to the above formula can indicate the angle at which the first adjusting screw 31 or the second adjusting screw 32 needs to be rotated, facilitating the operation of adjusting the height position and having high adjustment precision.

[0092] It should be understood that in the present application, the circuit connections are not drawn, and the circuit connections and the high-temperature protection of the circuit according to the prior art can be performed, but it is only necessary to meet the requirements that each heating unit 2 can be controlled by current, and that the damage of any heating unit 2 does not affect the normal operation of other heating units 2.

[0093] It should be understood that, in the present application, unless otherwise specified, the term "rotary connection" or "rotary mounting" means that only relative rotation can occur between the two, for example, the rotary connection of a hole and a shaft can be achieved by providing a shaft shoulder on the shaft and a limiting groove in the hole to limit the axial relative movement; the term "sliding connection" means that only relative sliding can occur between the two, for example, dovetail grooves, T-shaped grooves and the like.

[0094] The above description of the specific embodiments has further detailed the purposes, technical solutions and beneficial effects of the present application. It should be understood that the above description is only a specific embodiment of the present application and is not used to limit the protection scope of the present application. Any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present application shall be included in the protection scope of the present application.

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, Temperature monitoring components are installed on both the inner side of the upper furnace shell (11) and the inner side of the lower furnace shell (12); 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. The projections of the two ends of the heating wire (22) on the end face of the mounting ring (21) coincide. 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.

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 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.

5. A heating method for a pressure reactor, based on the heating device according to any one of claims 1 to 4, 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).

6. The heating method according to claim 5, 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.

7. The heating method according to claim 5, 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.

8. The heating method according to claim 7, 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 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.

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