Powder doping device

Abstract

The invention provides a powder doping device, which comprises an erected quartz glass cylinder and a heating kiln arranged on the circumferential surface of the quartz glass cylinder, and is characterized in that a breather pipe is erected in the quartz glass cylinder along the length direction of the quartz glass cylinder, one end of the breather pipe is sealed, the breather pipe is positioned in the top area in the quartz glass cylinder, and the other end of the breather pipe is sealed. A plurality of ventilation holes are formed in the bottom area, facing the interior of the quartz glass cylinder, of the ventilation pipe at intervals, and the ventilation pipe is a pipe body made of a high-temperature-resistant material. After powder is added into the quartz glass cylinder, along with rotation of the quartz glass cylinder, the powder can slowly rotate towards the middle area of the quartz glass cylinder and is heated by the heating kiln, protective gas is introduced along with the ventilation pipe, and the uniformly dispersed protective gas provides a reaction environment for quartz powder and a modified material; therefore, the quartz powder and the modified material can be fully reacted, and the generated impurities are discharged to the other end of the quartz glass cylinder along with the air flow, so that the purposes of doping, roasting and purifying are achieved.

Description

Technical Field

[0001] The invention generally relates to the field of quartz doping, and in particular to a powder doping device. Background Art

[0002] Doped quartz glass refers to adding a certain amount of impurity elements into quartz glass to change its optical, mechanical, electrical and other properties. Impurity elements have a great influence on the quality of high-purity quartz products. The content of alkali metals, transition metals, Al and B are key indicators of high-purity quartz raw materials, and the content of impurity elements varies according to the different uses of the prepared quartz glass. Among them, doped quartz glass is used in the optical field, electronic field, and medical field.

[0003] Doping elements usually include radium, neodymium, europium, terbium, cobalt, etc., which can be prepared by a variety of methods, such as sol-gel method, thermal reaction method, laser method, etc. A thermal reaction doping device before improvement includes a rotating quartz glass cylinder, a heating kiln arranged around the quartz glass cylinder, quartz powder and modified materials are added to one end of the quartz glass cylinder, and protective gas (wherein the protective gas is not limited to nitrogen, ammonia, carbon dioxide) is introduced into the inlet of the quartz glass cylinder. Under the high temperature of the heating device, the quartz powder and the modified material are doped to improve the physical and chemical properties of the quartz powder and the modified material, thereby improving the impurity removal effect.

[0004] However, since the protective gas is only introduced from the end, its flow and concentration in the quartz glass tube are uneven, which will also affect the doping effect of the quartz powder and the modified material. Summary of the invention

[0005] In view of the problems existing in the above-mentioned prior art, the present invention provides a powder doping device, comprising: a mounted quartz glass cylinder, and a heating kiln arranged on the circumference of the quartz glass cylinder, characterized in that a vent pipe is mounted in the quartz glass cylinder along the length direction of the quartz glass cylinder, one end of the vent pipe is sealed, the vent pipe is located in the top area of ​​the quartz glass cylinder, and the vent pipe is provided with a plurality of vent holes spaced apart toward the bottom area of ​​the quartz glass cylinder, and the vent pipe is a tube body made of high temperature resistant material. With the above technical features, after the quartz powder and the modified material are added into the quartz glass tube, as the quartz glass tube rotates, the mixed powder will slowly rotate toward the middle area of ​​the quartz glass tube and be heated by the heating kiln. With the protective gas introduced through the vent pipe, the quartz glass tube is evenly filled with the protective gas, which helps the quartz powder and the modified material to fully react, and the generated impurities are discharged to the other end of the quartz glass tube along with the air flow, thereby achieving the purpose of roasting and impurity removal. Moreover, since the vent pipe is arranged at the top of the quartz glass tube, the rotation of the quartz glass tube does not cause the powder to contact the vent pipe, but instead makes the protective gas dispersed more fully.

[0006] In some embodiments, a plurality of partitions made of high temperature resistant materials are arranged at intervals in the quartz glass cylinder, the partitions are fixed to the ventilation pipe, and the partitions and the bottom area of ​​the quartz glass cylinder leave a space for accommodating the passage of materials. Thus, with the arrangement of a plurality of partitions and ventilation holes, a plurality of interconnected chambers are formed in the quartz glass cylinder, which ensures the concentration of the protective gas distribution in each chamber, thereby slowing down the flow rate of the protective gas, so that the quartz powder and the modified material can fully react in the protective gas environment, and the space reserved between the partition and the bottom of the quartz glass cylinder will not affect the normal flow of the powder, so that the powder added in sequence can be continuously cleaned.

[0007] In some embodiments, at least one vent hole is provided on the vent pipe between the adjacent partitions. Thus, the vent hole and the partition cooperate with each other to ensure the concentration of the protective gas in the chamber formed between the two adjacent partitions, and further ensure the reaction efficiency of the quartz powder and the modified material in each chamber.

[0008] In some embodiments, the partition is provided with an air chamber interconnected with the internal space of the vent pipe, and the partition is provided with a plurality of boost ports interconnected with the air chamber on the side away from the inlet of the quartz glass tube, and the boost ports are arranged obliquely toward the inner wall of the quartz glass tube. Therefore, during the rotation of the quartz glass tube, the protective gas blown out of the boost port can ensure the reaction between the quartz powder and the improved material on the one hand, and reduce the adhesion of the mixed powder to the inner wall of the quartz glass tube on the other hand. Thirdly, by adjusting the gas flow rate, the powder can be promoted, and the boost port is arranged on the side of the quartz glass tube away from the feed port, which also prevents the powder from blocking the boost port.

[0009] In some embodiments, the heating kiln includes a bottom kiln and a top kiln with a cover disposed above the bottom kiln, the bottom kiln and the top kiln are provided with heating devices inside, and the quartz glass cylinder is disposed between the bottom kiln and the top kiln. Thus, the separately arranged heating kiln helps to maintain and replace the internal quartz glass cylinder, greatly improving the efficiency of inspection and troubleshooting, and the separately arranged heating kiln also helps to troubleshoot the heating device.

[0010] In some embodiments, a support base connected to the bottom kiln for rotation is provided at the tail of the bottom kiln, and a lifting seat for controlling the lifting of the bottom kiln is provided at the front bottom of the bottom kiln. Thus, the staff can adjust the inclination angle of the quartz glass cylinder through the lifting seat, and adjust the flow rate of the powder in the quartz glass cylinder as the quartz glass cylinder rotates, thereby realizing continuous powder addition and continuous doping and purification operations. The angle of the quartz glass cylinder can also be adjusted according to specific needs to control the flow rate of the powder so that the powder can undergo sufficient doping and purification reactions.

[0011] In some embodiments, wheels for supporting the inner wall of the quartz glass cylinder are symmetrically arranged on both sides of the partition, and the wheels are rotatably connected to the partition. Therefore, the vent pipe is set in the quartz glass cylinder, and multiple partitions are arranged inside it. The supporting pressure in the middle is relatively large, and it is very easy to cause damage to the vent pipe in a high temperature environment. Therefore, the setting of the wheel body plays an auxiliary supporting role for the vent pipe, and also avoids direct friction between the partition and the quartz glass cylinder, which not only prolongs the service life of the vent pipe, but also prolongs the service life of the quartz glass cylinder.

[0012] In some embodiments, the inner walls of the bottom kiln and the top kiln are paved with heat-insulating bricks, and the heating device is arranged on the surface of the heat-insulating bricks. Thus, the arrangement of the heat-insulating bricks effectively blocks the heat generated by the heating device from diffusing to the outside, and ensures the heating efficiency and heat preservation efficiency of the heating kiln.

[0013] In some embodiments, notches that fit with the quartz glass tube are provided at both ends of the bottom kiln. Thus, the notches not only play a role in positioning the quartz glass tube, but also reduce the diffusion of heat and reduce heat loss.

[0014] In some embodiments, a plurality of heat-resistant balls are embedded in the inner wall of the notch, and an embedding groove is provided at the notch of the quartz glass cylinder. Thus, the cooperation between the heat-resistant balls and the embedding groove of the quartz glass cylinder ensures the stable rotation of the quartz glass cylinder and reduces the rotation wear of the quartz glass cylinder.

[0015] It should be understood that the contents described in the summary of the invention are not intended to limit the key or important features of the embodiments of the present disclosure, nor are they intended to limit the scope of the present disclosure. Other features of the present disclosure will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 The overall structural schematic diagram of a powder doping device provided by an embodiment of the present invention is shown;

[0017] Figure 2 A schematic structural diagram of a heating kiln in a powder doping device provided by an embodiment of the present invention is shown;

[0018] Figure 3 A schematic diagram of the structure of a bottom kiln notch in a powder doping device provided by an embodiment of the present invention is shown;

[0019] Figure 4 A schematic structural diagram of a rotating mechanism in a powder doping device provided by an embodiment of the present invention is shown;

[0020] Figure 5A schematic diagram of the internal structure of a quartz glass cylinder in a powder doping device provided by an embodiment of the present invention is shown;

[0021] Figure 6 A schematic diagram of the structure of a partition in a powder doping device provided by an embodiment of the present invention is shown.

[0022] Explanation of symbols

[0023] 1. Support plate; 2. Support assembly; 21. Support base; 22. Lifting seat; 221. Bottom fixing part; 222. Top fixing part; 223. Lifting piece; 3. Heating kiln; 31. Bottom kiln; 311. Notch; 32. Top kiln; 33. Insulating brick; 331. Groove; 34. Heating device; 35. Heat-resistant ball; 4. Quartz glass cylinder; 41. Embedded groove; 42. Raised ridge; 5. Rotating mechanism; 51. Sleeve; 52. Elastic assembly; 521. Shrapnel; 53. Driven wheel; 54. Driving motor; 55. Driving wheel; 56. Driving belt; 6. Ventilation pipe; 61. Ventilation hole; 7. Partition; 71. Boosting port; 72. Wheel body. DETAILED DESCRIPTION

[0024] Hereinafter, preferred embodiments (or implementation modes) of the present invention will be described in detail with reference to the accompanying drawings.

[0025] The present invention provides a powder doping device, which includes a support plate 1, a support assembly 2 located at the bottom of the support plate 1, a heating kiln 3 located on the support plate 1, and a quartz glass tube 4 inserted into the heating kiln 3, and also includes a rotating mechanism 5 arranged on the support plate 1 to control the rotation of the quartz glass tube 4, and a vent pipe 6 arranged in the quartz glass tube 4. As the quartz glass tube 4 rotates, the support assembly 2 adjusts the angle of the quartz glass tube 4, so that the quartz powder and the modified material introduced into the quartz glass tube 4 can slowly move to the other end of the quartz glass tube 4, and under the action of the high temperature of the heating kiln 3 and the protective gas introduced into the vent pipe 6, the quartz powder and the modified material are continuously doped and purified, thereby ensuring the purification efficiency.

[0026] Reference below Figure 1-Figure 6 To describe a powder doping device provided by the present invention.

[0027] Figure 1 FIG. 1 is a schematic diagram showing the overall structure of a powder doping device provided by an embodiment of the present invention. Figure 1 As shown, a powder doping device provided in this embodiment includes a support plate 1, a support assembly 2 arranged at the bottom of the support plate 1, a heating kiln 3 arranged above the support plate 1, a quartz glass tube 4 passing through the interior of the heating kiln 3 along the length direction of the heating kiln 3, and a rotating mechanism 5 arranged at the rear of the heating kiln 3 for controlling the rotation of the quartz glass tube 4.

[0028] The length of the quartz glass tube 4 can be changed according to the actual working conditions. For example, in a high temperature atmosphere environment, the purification effect of the existing method depends on the reaction time of the quartz powder and the chlorine-containing mixed gas, and depends on the reaction temperature. When the temperature is high, the reaction of chlorine and metal impurities is accelerated, and thus the temperature rise may obtain a better purification effect. In addition, the purification effect also depends on the residence time of the quartz powder in the quartz glass tube 4. The coarse-grained powder is usually faster than the fine-grained body through the quartz glass tube 4. Therefore, the staff can adjust the advancement speed of the silicon dioxide powder in the quartz glass tube 4 so that the quartz powder is fully purified, and it is also possible to continuously carry out the operation of feeding without interruption.

[0029] The support assembly 2 includes a support base 21 arranged at the rear of the support plate 1, the bottom of the support base 21 is fixed on the ground, and the top thereof is rotatably connected to the support plate 1; the support assembly 2 also includes a lifting seat 22 arranged at the bottom of the front side of the support plate 1, the lifting seat 22 includes a bottom fixing portion 221 fixed to the ground and a top fixing portion 222 rotatably connected to the bottom of the support plate 1, and also includes a lifting member 223, the lifting member 223 can be a screw lift, or an electric push rod or a device with a lifting function such as an oil cylinder, both ends of which are rotatably connected to the top fixing portion 222 and the bottom fixing portion 221 to meet the lifting requirements of the front side of the support plate 1. The staff can adjust the initial angle of the quartz glass tube 4 by regulating the lifting member 223, and as the quartz glass tube 4 rotates, the powder in the quartz glass tube 4 is slowly displaced to the other end.

[0030] Figure 2 FIG. 1 is a schematic diagram showing the structure of a heating kiln 3 in a powder doping device provided by an embodiment of the present invention. Figure 2As shown, the heating kiln 3 includes a bottom kiln 31 and a top kiln 32 covered on the top of the bottom kiln 31. The bottom kiln 31 and the top kiln 32 can also be connected by rotation on one side and fixed to each other by a lock on the other side, which greatly facilitates the subsequent maintenance and replacement of the interior of the heating kiln 3 or the quartz glass tube 4. A large number of insulation bricks 33 are laid inside the bottom kiln 31 and the top kiln 32, and the area corresponding to the insulation bricks 33 and the quartz glass tube 4 is provided with a groove 331 that fits the quartz glass tube 4, and a heating device 34 is evenly embedded in the groove 331. In this embodiment, the heating device 34 takes an electric heating wire as an example, so as to ensure uniform heating of the quartz glass tube 4. The heating device 34 can meet different atmosphere reaction temperatures, including a low temperature section of 560℃-800℃, and a high temperature section of 1000℃-1400℃. Both ends of the bottom kiln 31 and the top kiln 32 are provided with slots 311 that fit with the quartz glass tube 4, so that the top kiln 32 and the bottom kiln 31 are well closed, and the heating device 34 fits more closely with the quartz glass tube 4 with less gap, thereby improving the thermal efficiency of heat transfer between the electric heating wire and the quartz glass tube 4.

[0031] Figure 3 FIG. 1 shows a schematic diagram of the structure of a powder doping device provided in an embodiment of the present invention at a notch 311 of a bottom kiln 31, referring to FIG. Figure 3 As shown, in order to ensure the smooth rotation of the quartz glass cylinder 4 in the heating kiln 3, a plurality of heat-resistant balls 35 are evenly embedded at the edge of the notch 311 of the bottom kiln 31, and the quartz glass cylinder 4 is thickened at the notch 311, so that an embedding groove 41 is formed at the notch 311 of the quartz glass cylinder 4. With the cooperation of the heat-resistant balls 35 and the embedding groove 41, the smooth rotation of the quartz glass cylinder 4 in the heating kiln 3 is ensured, and the friction loss between the notch 311 of the bottom kiln 31 and the quartz glass cylinder 4 is reduced. In addition, due to the thickening treatment of the quartz glass cylinder 4, it also has a barrier effect on heat, which greatly increases the heat preservation effect inside the heating kiln 3.

[0032] Figure 4 FIG. 1 is a schematic diagram showing the structure of a rotating mechanism in a powder doping device provided by an embodiment of the present invention. Figure 4As shown, although the thermal expansion coefficient of quartz glass is very small, in order to ensure the service life of the quartz glass tube 4, its driving structure takes into account flexible connection to reduce the damage of the quartz glass tube 4 caused by the fixed connection with the quartz glass tube 4. The rotating mechanism 5 includes a sleeve 51 sleeved at the tail of the quartz glass tube 4, and the diameter of the inner wall of the sleeve 51 is greater than the diameter of the outer wall of the quartz glass tube 4, so that a gap is left between the sleeve 51 and the quartz glass tube 4, and the inner wall of the sleeve 51 is provided with multiple groups of elastic components 52, and the elastic components 52 include two springs 521, one end of the two springs 521 is connected to each other and fixed on the inner wall of the sleeve 51, and the other end is symmetrically arranged and bent in opposite directions. Under the action of the multiple groups of elastic components 52, the outer wall of the quartz glass tube 4 is clamped between the multiple groups of springs 521, and even if the quartz glass tube 4 is deformed under the action of temperature, the sleeve 51 can also ensure the grip of the quartz glass tube 4 by the elastic bending of the springs 521.

[0033] The rotating mechanism 5 further includes a driven wheel 53 coaxially fixed to the outer circumference of the sleeve 51, a driving motor 54 fixed to the support plate 1, a driving wheel 55 coaxially fixed to the output shaft of the driving motor 54, and a driving belt 56 sleeved on both the driven wheel 53 and the driving wheel 55. Due to the flexible connection between the sleeve 51 and the quartz glass tube 4, direct contact between the driving belt 56 and the quartz glass tube 4 is avoided, and the influence of high temperature on the service life of the driving belt 56 is avoided. In addition, the flexible connection also greatly improves the convenience of disassembly of the sleeve 51 and the end of the quartz glass tube 4, and greatly improves the maintenance efficiency.

[0034] In order to improve the synchronization of the rotation of the sleeve 51 and the quartz glass cylinder 4 , the quartz glass cylinder 4 is provided with ridges 42 in the area in contact with the elastic component 52 to increase the friction with the elastic component 52 , thereby ensuring the normal driving of the quartz glass cylinder 4 by the driving motor 54 .

[0035] Figure 5 FIG. 4 is a schematic diagram showing the internal structure of a quartz glass cylinder 4 in a powder doping device provided by an embodiment of the present invention. Figure 5 As shown, a vent pipe 6 made of a high temperature resistant material is arranged inside the quartz glass tube 4 along the length direction of the quartz glass tube 4, the end of the vent pipe 6 is sealed, and the vent pipe 6 is located in the top area of ​​the quartz glass tube 4, and the vent pipe 6 is provided with a plurality of vent holes 61 spaced apart along the length direction of the vent pipe 6 toward the bottom area inside the quartz glass tube 4, so that during the doping and roasting process, the protective gas supplied from the outside can participate in the doping and purification reaction, and since the protective gas is supplied into the quartz glass tube 4 through the vent pipe 6, the protective gas is dispersed more evenly, thereby avoiding the inadequate reaction caused by the uneven concentration distribution caused by the gas supply at the inlet end of the quartz glass tube 4.

[0036] In order to slow down the flow rate of the protective gas, a plurality of partitions 7 made of high temperature resistant material are also arranged in the quartz glass tube 4. The partitions 7 are arranged at intervals and fixed to the vent pipe 6, and the vent pipe 6 between adjacent partitions 7 is provided with at least one vent hole 61, so that the protective gas discharged from the vent hole 61 can be fully retained in the space between adjacent partitions 7, and a gap is left between the peripheral side of each partition 7 and the inner wall of the quartz glass tube 4, and a large gap is left at the bottom of the partition 7 for powder to pass through, which ensures the normal transportation of materials while ensuring the flow of gas. Through the arrangement of multiple partitions 7, the flow rate of the protective gas is slowed down, so that the quartz powder and the modified material can be fully doped, roasted and purified.

[0037] Figure 6 FIG. 1 is a schematic diagram showing the structure of a partition plate 7 in a powder doping device provided by an embodiment of the present invention. Figure 5 , Figure 6 As shown, each partition 7 is provided with an air chamber interconnected with the inside of the vent pipe 6, and each partition 7 is provided with a plurality of boosting ports 71 on the side away from the feed port of the quartz glass cylinder 4. The boosting ports 71 are located at the edge of the partition 7 and are obliquely opened toward the inner wall of the adjacent quartz glass cylinder 4, so that the gas blown out of the boosting ports 71 can act on the inner wall of the quartz glass cylinder 4 and blow away the powder adhering to the inner wall of the quartz glass cylinder 4. Moreover, since the vent pipe 6 is supported only by the supporting structures outside the two ends of the quartz glass cylinder 4, if the length of the quartz glass cylinder 4 is too long, it is very easy to cause a large supporting pressure in the middle of the vent pipe 6, which is easy to cause damage to the vent pipe 6. Therefore, two wheel bodies 72 rotatably connected to the partition 7 are symmetrically arranged at the two edges of the bottom of each partition 7, and supported on the inner wall of the quartz glass cylinder 4, thereby playing an auxiliary supporting role for the vent pipe 6, and in the process of the rotation of the quartz glass cylinder 4, the partition 7 is also avoided. Direct contact with the quartz glass cylinder 4 is also avoided, thereby extending the service life of the quartz glass cylinder 4 and the vent pipe 6.

[0038] When the quartz glass tube 4 rotates, since the vent pipe 6 is arranged in the top area of ​​the quartz glass tube 4, the silicon dioxide powder cannot touch the vent pipe 6, thereby ensuring the normal operation of the vent hole 61; and the booster port 71 is located on the side of the partition 7 away from the feeding end of the quartz glass tube 4, so it is difficult for the quartz powder to block the booster port 71. When the quartz powder rotates to the surrounding side following the inner wall of the quartz glass tube 4, the gas blown out of the booster port 71 can, on the one hand, blow away the powder adhering to the inner wall of the quartz glass tube 4, and on the other hand, the gas blown out of the booster port 71 also plays a role in blowing away and stirring, which is beneficial to the full reaction of the quartz powder and the modified material. Thirdly, it can also play a boosting role on the material by adjusting the flow rate of the gas spray, which is beneficial to the flow and discharge of the material. Fourthly, the gas sprayed is also beneficial to drive the gas flow, thereby smoothly discharging the exhaust gas through the discharge end of the quartz glass tube 4.

[0039] In the description of this specification, the terms "connection", "installation", "fixation" and the like should be understood in a broad sense. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection or an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0040] The above are only preferred embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A powder doping device, comprising: A quartz glass cylinder (4) is installed, and a heating kiln (3) is arranged on the circumference of the quartz glass cylinder (4), characterized in that a ventilation pipe (6) is installed inside the quartz glass cylinder (4) along the length direction of the quartz glass cylinder (4), one end of the ventilation pipe (6) is sealed, the ventilation pipe (6) is located in the top area of ​​the quartz glass cylinder (4), and the ventilation pipe (6) is provided with a plurality of ventilation holes (61) spaced apart toward the bottom area of ​​the quartz glass cylinder (4), and the ventilation pipe (6) is a tube body made of high temperature resistant material.

2. A powder doping device according to claim 1, characterized in that: A plurality of partitions (7) made of high-temperature resistant material are arranged at intervals in the quartz glass cylinder (4); the partitions (7) and the ventilation pipe (6) are fixed to each other; and a clearance space for accommodating the passage of materials is left between the partitions (7) and the bottom area in the quartz glass cylinder (4).

3. A powder doping device according to claim 2, characterized in that: At least one vent hole (61) is provided on the vent pipe (6) between adjacent partitions (7).

4. A powder doping device according to claim 2, characterized in that: An air chamber interconnected with the internal space of the ventilation pipe (6) is arranged in the partition (7), and a plurality of boosting ports (71) interconnected with the air chamber are provided on the side of the partition (7) away from the inlet of the quartz glass cylinder (4), and the boosting ports (71) are arranged obliquely toward the inner wall of the quartz glass cylinder (4).

5. The powder doping device according to claim 1, characterized in that: The heating kiln (3) comprises a bottom kiln (31) and a top kiln (32) covered on the top of the bottom kiln (31), heating devices (34) are arranged inside the bottom kiln (31) and the top kiln (32), and the quartz glass cylinder (4) is inserted between the bottom kiln (31) and the top kiln (32).

6. A powder doping device according to claim 5, characterized in that: A supporting base (21) rotatably connected to the bottom kiln (31) is arranged at the rear of the bottom kiln (31), and a lifting seat (22) for controlling the lifting of the bottom kiln (31) is arranged at the front bottom of the bottom kiln (31).

7. A powder doping device according to claim 2, characterized in that: Wheel bodies (72) for supporting the inner wall of the quartz glass cylinder (4) are symmetrically arranged on both sides of the partition (7), and the wheel bodies (72) are rotatably connected to the partition (7).

8. The powder doping device according to claim 5, characterized in that: The inner walls of the bottom kiln (31) and the top kiln (32) are paved with heat-insulating bricks (33), and the heating device (34) is arranged on the surface of the heat-insulating bricks (33).

9. The powder doping device according to claim 5, characterized in that: The two ends of the bottom kiln (31) are provided with notches (311) that fit with the quartz glass cylinder (4).

10. A powder doping device according to claim 9, characterized in that: A plurality of heat-resistant balls (35) are embedded in the inner wall of the notch (311), and an embedding groove (41) is provided in the quartz glass cylinder (4) at the notch (311).

Images