Reaction furnace

Abstract

The application discloses a reaction furnace, comprising: a furnace body, the furnace body comprises a top cover part, a low-temperature section, a high-temperature section and a bottom cover part from top to bottom in the vertical direction, a discharge port is arranged on the top of the low-temperature section, a first feeding port is arranged on the top of the high-temperature section, a heater is arranged on the outer wall of the high-temperature section, a second feeding port is arranged on the side of the bottom cover part, and a third feeding port is arranged on the bottom surface of the bottom cover part; a cooling device, comprising a cooling pipe, at least part of the cooling pipe extends into the inside of the high-temperature section, cooling water flows in the cooling pipe; and a distribution plate. The reaction furnace utilizes the heater to heat the side wall of the high-temperature section, and cooperates with the cooling device to cool the space inside the high-temperature section, so that the real-time temperature inside the high-temperature section can be accurately controlled, the temperature control capability of the reaction furnace is improved, and the purity of trichlorosilane is improved. Moreover, the heater does not contact the reactants inside the furnace body, and the risk of short circuit can be reduced.

Description

Technical Field

[0001] This application relates to the field of synthetic reactor technology, and more particularly to a reactor. Background Technology

[0002] To recover the low-value fine silicon powder generated during the production of granular silicon, the low-pressure synthesis process for producing trichlorosilane is a crucial step. The reactor for low-pressure synthesis of trichlorosilane is a commonly used piece of equipment in this field. Its working principle involves reacting fine silicon powder with hydrogen chloride to produce trichlorosilane (TCS), and its normal operating temperature is 280℃~340℃.

[0003] Industrial silicon powder is used as the reaction raw material. The furnace wall is mostly indirect heat exchange form. Most of them use heat transfer oil half pipe to heat the gas in the furnace or preheater to heat hydrogen to a certain reaction temperature and mix it with hydrogen chloride before sending it into the reactor for synthesis reaction. However, it is difficult to ensure that the working temperature of fine silicon powder and hydrogen chloride in the reactor is stable between 280℃ and 340℃. Therefore, the purity of the produced trichlorosilane (TCS) is not high. Utility Model Content

[0004] To address the aforementioned technical problems, this application provides a reactor.

[0005] This application provides a reactor, comprising: The furnace body includes, from top to bottom, a top cover, a low-temperature section, a high-temperature section and a bottom cover in the vertical direction. The top of the low-temperature section has a discharge port, the top of the high-temperature section has a first inlet port, the outer wall of the high-temperature section is equipped with a heater, the side of the bottom cover has a second inlet port, and the bottom surface of the bottom cover has a third inlet port. A cooling device includes a cooling pipe, at least a portion of which extends into the inner side of the high-temperature section, and cooling water flows through the cooling pipe. A distribution plate is disposed between the high-temperature section and the bottom cover. The distribution plate has a material passage hole for connecting the high-temperature section and the bottom cover.

[0006] Optionally, the heater is fitted onto the outer wall of the high-temperature section and is used to heat the outer wall of the high-temperature section.

[0007] Optionally, the heater has an annular heating surface that is in contact with the outer wall of the high-temperature section.

[0008] Optionally, the heater is provided with an outer wall temperature measuring port extending to the outer wall of the high-temperature section.

[0009] Optionally, multiple temperature measuring ports are arranged along the height direction on the outer wall.

[0010] Optionally, the bottom cover is provided with a feed thermometer for detecting the temperature of the material entering from the second feed port.

[0011] Optionally, the furnace body is provided with an in-furnace thermometer, which extends along the height direction and has multiple temperature measuring points in the vertical direction, with at least two of the temperature measuring points located inside the high-temperature section.

[0012] Optionally, a buffer slot is provided on the top surface of the distribution plate, and all the material passage holes are connected to the buffer slot.

[0013] Optionally, the distribution plate is a concave plate with a downward arch at the center.

[0014] Optionally, the cooling pipe includes a straight pipe extending in a vertical direction, the bottom end of the straight pipe extending to the inside of the high-temperature section, the top end of the straight pipe communicating with cooling water, and the top end of the straight pipe having a steam outlet communicating with the outside.

[0015] Optionally, a steam pipe is sleeved inside the straight pipe, and a space for accommodating cooling water is formed between the steam pipe and the straight pipe. The bottom end of the steam pipe and the bottom end of the straight pipe have a channel for steam to pass through, and the top end of the steam pipe is connected to the steam outlet.

[0016] Optionally, the bottom end of the straight tube is provided with a guide block, the bottom of the guide block has a tip, and the tip smoothly transitions to the side wall of the straight tube through a plane or an arc surface.

[0017] Optionally, the cooling device further includes a stabilizing component, with multiple straight pipes arranged inside the furnace body, and at least two straight pipes connected through the stabilizing component.

[0018] Optionally, multiple stabilizing components are arranged in a vertical direction.

[0019] Optionally, the cooling device further includes a support assembly, the support assembly including a support member having a first support end and a second support end; The first support end abuts against the side wall of the furnace body, the second support end abuts against the stabilizing component, and the support is horizontally disposed between the side wall of the furnace body and the stabilizing component.

[0020] Optionally, the cooling device further includes a cooling cylinder disposed on the top of the furnace body, a first sealing plate being provided between the cooling cylinder and the top cover, the top end of the straight pipe passing upward through the first sealing plate and communicating with the interior of the cooling cylinder, the side wall of the straight pipe being sealed to the first sealing plate, the cooling cylinder being in communication with cooling water, and a steam outlet being provided at the top of the cooling cylinder.

[0021] Optionally, the cooling pipe includes an inlet end and an outlet end, the inlet end being located below the high-temperature section and used to connect cooling water, and the outlet end being located above the high-temperature section.

[0022] The technical solution provided in this application has the following advantages compared with the prior art: The reactor provided in this application utilizes a heater to heat the sidewalls of the high-temperature section, while a cooling device cools the internal space of the high-temperature section. This alternating heating and cooling allows for precise real-time temperature control within the high-temperature section, improving the reactor's temperature control capability. Specifically, it facilitates temperature control within the high-temperature section between 280℃ and 340℃, thereby increasing the purity of trichlorosilane, suppressing side reactions (such as the formation of silicon tetrachloride), and producing trichlorosilane with a selectivity ≥85%. The product purity meets the requirements of the photovoltaic and semiconductor industries for high-purity silicon raw materials. Furthermore, the heater does not come into contact with the reactants inside the furnace, reducing the risk of short circuits. Attached Figure Description

[0023] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0024] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 This is a schematic diagram of the reactor structure described in the embodiments of this application; Figure 2 This is a schematic diagram of the structure of one of the cooling devices described in the embodiments of this application; Figure 3 for Figure 2 A magnified view of a section at point A in the middle; Figure 4 This is a front view of the support member described in the embodiment of this application; Figure 5 This is a top view of the support member described in the embodiment of this application; Figure 6 This is a schematic diagram of another reactor described in an embodiment of this application; Figure 7 This is a flowchart illustrating the operation of the reactor described in the embodiments of this application.

[0026] Among them, 11, top cover; 12, low temperature section; 13, high temperature section; 14, bottom cover; 15, enlargement section; 161, first inlet; 162, second inlet; 163, outlet; 164, third inlet; 17, fastener; 18, first sealing plate; 19, second sealing plate; 2. Heater; 31. Straight pipe; 311. Guide block; 32. U-shaped pipe; 33. Cooling cylinder; 34. Stabilizing component; 35. Support component; 351. Pad; 352. Protective plate; 353. Support beam; 354. Connecting beam; 36. Steam pipe; 4. Distribution board; 41. Buffer slot; 51. External wall temperature measuring port; 52. Feed thermometer; 53. Furnace internal thermometer; 54. First pressure gauge; 55. Second pressure gauge. Detailed Implementation

[0027] To better understand the above-mentioned objectives, features, and advantages of this application, the solution of this application will be further described below. It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other.

[0028] Many specific details are set forth in the following description in order to provide a full understanding of this application, but this application may also be implemented in other ways different from those described herein; obviously, the embodiments in the specification are only some embodiments of this application, and not all embodiments.

[0029] Based on this, this embodiment provides a reactor. The following detailed description is provided through specific embodiments: Reference Figures 1 to 6 As shown, the reactor provided in this embodiment includes: The furnace body, in the vertical direction from top to bottom, includes a top cover 11, a low-temperature section 12, a high-temperature section 13, and a bottom cover 14. The top cover 11 and the low-temperature section 12 can be integrally formed or connected by a flange or other structure. Similarly, the high-temperature section 13 and the bottom cover 14 can be integrally formed or connected by a flange or other structure.

[0030] The low-temperature section 12 has a discharge port 163 at its top, and the high-temperature section 13 has a first inlet port 161 at its top. A heater 2 is installed on the outer wall of the high-temperature section 13. A second inlet port 162 is located on the side of the bottom cover 14, and a third inlet port 164 is located on the bottom surface of the bottom cover 14. The first inlet port 161 is used to allow silicon powder to enter the furnace, the second inlet port 162 is used to allow hydrogen chloride to enter the furnace, and the third inlet port 164 is used to allow hydrogen gas to enter the furnace. The discharge port 163 is used to allow the trichlorosilane (TCS) mixed gas to exit the furnace. The low-temperature section 12 and the high-temperature section 13 can be identified by the presence of a heater 2 on their outer walls. The low-temperature section 12 and the high-temperature section 13 together form a reaction chamber.

[0031] The cooling device includes cooling pipes, at least a portion of which extend into the interior of the high-temperature section 13, and cooling water flows through the cooling pipes. When the furnace temperature is too high, the cooling device can reduce the temperature inside the high-temperature section 13 through flash evaporation or evaporation of the cooling water.

[0032] A distribution plate 4 is disposed between the high-temperature section 13 and the bottom cover 14. The distribution plate 4 has a material passage hole for connecting the high-temperature section 13 and the bottom cover 14. When the hydrogen chloride mixture enters the bottom cover 14, it passes through the material passage hole on the distribution plate 4 and enters the high-temperature section 13 to react with the silicon powder.

[0033] The high-temperature section 13 and the low-temperature section 12 are the main structures of the furnace body. The whole furnace body is a cylindrical structure. The furnace body is made of high-temperature resistant austenitic stainless steel. The stainless steel inner wall and metal internal parts are sprayed with a coating that is resistant to high-temperature hydrogen chloride or chloride ion corrosion, thereby improving the service life of the equipment.

[0034] The reactor provided in this embodiment utilizes heater 2 to heat the sidewall of the high-temperature section 13, while a cooling device cools the internal space of the high-temperature section 13. This alternating heating and cooling allows for precise real-time temperature control within the high-temperature section 13, improving the reactor's temperature control capability. Specifically, it facilitates maintaining the temperature of the high-temperature section 13 between 280℃ and 340℃, thereby increasing the purity of trichlorosilane, suppressing side reactions (such as the formation of silicon tetrachloride), and producing trichlorosilane with a selectivity ≥85%. The product purity meets the requirements of the photovoltaic and semiconductor industries for high-purity silicon raw materials. Furthermore, heater 2 does not come into contact with the reactants inside the furnace, reducing the risk of short circuits.

[0035] In some embodiments, the heater 2 is sleeved on the outer wall of the high-temperature section 13 and is used to heat the outer wall of the high-temperature section 13. That is, the heater 2 can be annular to ensure that the entire cylindrical high-temperature section 13 is heated evenly and that the heat emitted by the heater 2 is absorbed evenly on the periphery. Further, the heater 2 can be annular, and the distance between each part of the heater 2 and the outer wall of the high-temperature section 13 is the same.

[0036] Based on the above-mentioned high-temperature section 13 setting, the temperature consistency of the high-temperature section 13 can be significantly improved, thereby avoiding the situation where the temperature of the high-temperature section 13 is uneven and affects the purity of trichlorosilane.

[0037] In a further embodiment, the heater 2 has an annular heating surface that is in contact with the outer wall of the high-temperature section 13. That is, the heater 2 can directly heat the outer wall of the high-temperature section 13 through the annular heating surface in contact with the outer wall of the high-temperature section 13, thereby significantly improving heating efficiency and thus controlling the temperature of the high-temperature section 13 more accurately and quickly.

[0038] The heater 2 can be formed by splicing two 180-degree fan rings or three 60-degree fan rings, as long as it can form a complete heating structure that wraps around the outer wall of the high-temperature section 13. By covering the outer wall of the high-temperature section 13, not only can the heating area of ​​the high-temperature section 13 be increased, but the temperature uniformity of the internal environment of the high-temperature section 13 can also be ensured, avoiding local overheating or underheating.

[0039] In some embodiments, the heater 2 is provided with an outer wall temperature measuring port 51 extending to the outer wall of the high-temperature section 13; through the outer wall temperature measuring port, the measuring end of the thermometer can be directly contacted to the outer wall of the high-temperature section 13 from the outside, thereby accurately monitoring the temperature of the side wall of the high-temperature section 13, and thus more accurately and quickly adjusting the power of the heater 2 so that the interior of the high-temperature section 13 is at a suitable reaction temperature.

[0040] Continue to refer to Figure 1 As shown, multiple temperature measuring ports 51 are arranged along the height direction of the heater 2 on the outer wall. Multiple thermometers are installed through the multiple temperature measuring ports to measure the temperature at different height positions on the outer wall of the high-temperature section 13.

[0041] In some further embodiments, multiple heaters 2 may be arranged on the outer wall of the high-temperature section 13, with the multiple heaters 2 arranged vertically, wherein each heater 2 can be operated and its power controlled independently. Each heater 2 is provided with at least two temperature measuring ports in the height direction.

[0042] By using multiple heaters 2 and multiple temperature measuring ports, the power of different heaters 2 can be adjusted in a timely manner according to the temperature at different heights of the outer wall of the high-temperature section 13, so as to ensure that the temperature inside the high-temperature section 13 can always be maintained between 280℃ and 340℃, thereby improving the purity of trichlorosilane.

[0043] The inner and outer walls of the high-temperature section 13 can be sandblasted. The roughness of the furnace wall surface directly affects the thermal efficiency of radiant heat. Furthermore, sandblasting can be performed using a 100mm blasting method, achieving a surface roughness of 7.2~8.1μm. After sandblasting, a coating is applied to the inner surface of the furnace wall, which not only provides resistance to high-temperature hydrogen chloride corrosion but also extends the equipment's lifespan.

[0044] Continue to refer to Figure 1 As shown, a feed thermometer 52 is installed inside the bottom cover 14 to detect the temperature of the material entering from the second feed port 162. That is, the feed thermometer 52 is used to detect the inlet temperature of hydrogen chloride. When the reaction temperature in the bed is detected to be concentrated in the lower layer of the bed, the amount of hydrogen gas in the third feed port 164 can be increased to dilute the concentration of hydrogen chloride and reduce the displayed temperature of the feed thermometer 52, thereby controlling the reaction area in the bed and avoiding local heat accumulation.

[0045] In some embodiments, an in-furnace thermometer 53 is provided inside the furnace body. The in-furnace thermometer 53 extends along the height direction and has multiple temperature measuring points in the vertical direction, with at least two measuring points located inside the high-temperature section 13. By setting the in-furnace thermometer 53, the temperature at different height positions inside the furnace can be detected in real time. Therefore, the heater 2 and the cooling device can be adjusted according to the real-time temperature at different positions inside the furnace, so that the temperature inside the high-temperature section 13 can always be accurately maintained between 280°C and 340°C.

[0046] Optionally, a buffer groove 41 is formed on the top surface of the distribution plate 4, and all material passage holes are connected to the buffer groove 41. The buffer groove 41 on the top surface of the distribution plate 4 has a sufficient coverage area. Furthermore, the periphery of the buffer groove 41 can be close to the periphery edge of the distribution plate 4, forming a groove on the top of the distribution plate 4 for buffering gas, thereby reducing local gas flow rate fluctuations, making it less prone to flow deviation, and further improving the uniformity of gas distribution into the high-temperature section 13.

[0047] Optionally, the distribution plate 4 is a concave plate with a downward arch in the center. It should be understood that the top of the distribution plate 4 forms a downward concave groove structure, and the bottom of the distribution plate 4 protrudes downward, forming a partially spherical structure as a whole.

[0048] In other words, the distribution plate 4 forms a concave head at the bottom of the high-temperature section 13. Based on its curved surface structure, this concave head converts pressure into compressive stress components through the spherical curvature under internal pressure. The stress is evenly distributed along the wall thickness, and the transition zone (circular arc segment) can alleviate stress concentration at geometric abrupt changes. Moreover, the distribution plate 4 of this concave head has high load-bearing efficiency (membrane stress bearing). Under the same internal pressure and temperature, the required thickness is about 1 / 3 to 1 / 2 thinner than that of a flat head (straight plate distribution plate 4), reducing material usage while reducing thermal stress caused by temperature gradient due to thick cross-section. Under external pressure, the curved surface shape of the spherical surface and the transition zone has natural resistance to external pressure instability (the buckling critical pressure of the curved surface structure is much higher than that of the flat surface). Under external pressure, the distribution plate 4 of this concave head is less prone to local depression or overall buckling.

[0049] The curved distribution plate 4 can extend freely in the radial and circumferential directions (such as when the radius of the sphere increases) and provide flexible support (sleeve) during thermal expansion, reducing expansion constraint stress and avoiding deformation concentration. Moreover, the thickness of the distribution plate 4, which is a concave end cap, can be thinner than that of the straight plate distribution plate 4, resulting in more uniform temperature distribution at high temperatures, smaller internal and external temperature differences, and lower thermal stress amplitude.

[0050] When the distribution plate 4 is a curved structure, it can be made of metal. In this case, a cone-shaped nozzle can be set on the distribution plate 4 to achieve communication between the upper and lower spaces of the distribution plate 4, and hydrogen and hydrogen chloride can be injected into the high-temperature section through the nozzle.

[0051] When the distribution plate 4 is a straight plate structure, it can be an inorganic non-metallic material. Carbon-ceramic composite porous materials or SiC-coated C / C composite materials are recommended. The porosity and pore size distribution are controlled during the material manufacturing process. Generally, the micropore diameter should be ≤ 1 / 3 to 1 / 5 of the silicon powder particle size, and the porosity should be 30% to 45%. The main function of the distribution plate 4 is to ensure uniform gas distribution, preventing silicon powder from clogging the pores and ensuring uniform gas distribution, avoiding flow deviation, and improving the efficiency of the gas-solid reaction.

[0052] In some embodiments, the high-temperature section 13 and the bottom cover 14 are connected by a flange, and the distribution plate 4 is made of inorganic non-metallic material and can be fixed at the flange connection between the high-temperature section 13 and the bottom cover 14 by C / C fasteners 17.

[0053] Optionally, the cooling pipe includes a straight pipe 31 extending in a vertical direction, the bottom end of the straight pipe 31 extending to the inside of the high-temperature section 13, the top end of the straight pipe 31 communicating with cooling water, and the top end of the straight pipe 31 having a steam outlet communicating with the outside.

[0054] After the cooling water is introduced into the cooling pipe, it flows directly to the high-temperature section 13 under the combined action of pressure and gravity. Then, it absorbs heat through evaporation, thereby reducing the temperature of the high-temperature section 13. The part that turns into steam can go up along the straight pipe 31 until it is discharged from the steam outlet.

[0055] Among them, since the material selection of straight tube 31 must take into account the corrosion of high-temperature hydrogen chloride, the material of straight tube 311 can be 316L which is resistant to hydrogen chloride corrosion, or Hastelloy C-276 or titanium-palladium alloy TA9 can be considered. The outer wall of straight tube 31 is polished (roughness Ra≤0.8μm) to further reduce the friction between silicon powder and tube wall and reduce the adhesion rate of silicon powder.

[0056] Furthermore, a steam pipe 36 is fitted inside the straight pipe 31, forming a space between the steam pipe 36 and the straight pipe 31 for accommodating cooling water. The bottom end of the steam pipe 36 and the bottom end of the straight pipe 31 have a channel for steam to pass through, and the top end of the steam pipe 36 is connected to the steam outlet.

[0057] Continue to refer to Figures 1 to 3 As shown, the bottom end of the straight tube 31 is provided with a guide block 311, the bottom of the guide block 311 has a tip, and the tip and the side wall of the straight tube 31 are smoothly transitioned through a plane or arc surface.

[0058] The guide block 311 can be a plug at the bottom of the straight pipe 31, that is, the top and bottom of the straight pipe 31 are both open. The top opening is used to pass in cooling water and to discharge steam. The guide block 311 is installed at the bottom opening and blocks the bottom opening.

[0059] The guide block 311 can specifically adopt a tapered structure that is wider at the top and narrower at the bottom. It is inserted into the wall of the straight pipe 31 and then welded, resulting in good pressure resistance. The outer diameter of the guide block 311 can be the same as the outer diameter of the straight pipe 31. That is to say, in addition to having an insertion section for inserting into the straight pipe 31, the guide block 311 also has a portion that covers the bottom end face of the straight pipe 31. The portion of the guide block 311 that covers the bottom end face of the straight pipe 31 smoothly transitions from the center to the outermost side.

[0060] The guide block 311 extends into the straight pipe 31 at a height h of 5~10mm, the cone angle can be set to 45°~50°, and the bottom rounded corner can be set to minR5 for transition. The guide block 311 adopts a conical structure for smooth transition, which can reduce gas wear, extend service life, and at the same time reduce gas resistance, ensuring the smooth flow of hydrogen chloride toward the high-temperature section 13.

[0061] Optionally, the cooling device also includes a stabilizing component 34, with multiple straight pipes 31 arranged in the furnace body, and at least two straight pipes 31 connected by the stabilizing component 34.

[0062] Optionally, multiple straight pipes 31 can be arranged in an equilateral triangle or square on the first sealing plate 18, with the pipe spacing being 1.5 to 1.8 times that of the straight pipes 31, to reduce dead angles in the flow channel.

[0063] Optionally, multiple straight tubes 31 are evenly arranged inside the furnace body. Furthermore, they can be arranged in multiple layers to improve cooling efficiency and cooling uniformity.

[0064] Since the straight pipe 31 needs to extend a certain length vertically inside the furnace and is in a suspended state, the suspended parts of multiple straight pipes 31 can be connected into one unit by the setting of the stabilizing component 34 and the first sealing plate 18, and the multiple straight pipes 31 can support each other, thereby improving the stability of all straight pipes 31 inside the furnace.

[0065] Optionally, multiple stabilizing components 34 are arranged vertically. Specifically, the stabilizing components 34 can be plate-shaped structures with multiple support holes through which the straight pipe 31 passes. The stabilizing components 34 are evenly arranged vertically, and a set distance is spaced between every two stabilizing components 34 to ensure that the outer wall of the straight pipe 31 receives uniform lateral support force.

[0066] Continue to refer to Figure 1 , Figure 2 as well as Figures 4 to 6 As shown, the cooling device also includes multiple support components, each including a support member 35. The support member 35 has a first support end and a second support end. The first support end abuts against the side wall of the furnace body, and the second support end abuts against the stabilizing component 34. The support member 35 is horizontally positioned between the side wall of the furnace body and the stabilizing component 34. The second support end can also be directly supported on the side wall of the straight pipe 31. In other words, the stabilizing component 34 connects the suspended portions of multiple straight pipes 31 together, thereby providing support for each other. The support components establish a connection between the straight pipes 31 and the side wall of the furnace body, further improving the stability of the straight pipes 31 inside the furnace body.

[0067] Furthermore, the support member 35 includes a pad 351 located at the first support end, a guard plate 352 located at the second support end, and a support beam 353 located between the pad 351 and the guard plate 352. The support beam 353 is horizontally positioned to transfer the force on the straight pipe 31 to the side wall of the furnace body, reducing the horizontal swaying of the straight pipe 31. The support beam 353 is detachably connected to the pad 351 and / or the guard plate 352, facilitating the installation and removal of the support member 35. Specifically, the support beam 353 can be connected to the pad 351 and / or the guard plate 352 by means of screws, snap-fits, or other methods.

[0068] A buffer layer may be provided between the pad 351 and the side wall of the furnace body, and / or a buffer layer may be provided between the guard plate 352 and the stabilizing component 34.

[0069] Furthermore, when the inner wall of the furnace body is an arc-shaped structure, the pad 351 is set as an arc-shaped curved plate so that it can fit better with the inner wall of the furnace body. When the edge of the stabilizing component 34 is an arc-shaped structure, the guard plate 352 is set as an arc-shaped curved plate so that it can fit better with the edge of the stabilizing component 34.

[0070] The support beam 353 and the pad 351 can be connected by a connecting beam 354. The connecting beam 354 can have a long hole extending radially along the furnace body. The connecting beam 354 and the support beam 353 are connected by bolts installed on the long hole, thereby reducing the impact of thermal expansion and contraction of the furnace body.

[0071] Optionally, the cooling device further includes a cooling cylinder 33 disposed on the top of the furnace body. A first sealing plate 18 is provided between the cooling cylinder 33 and the top cover 11. The top end of the straight pipe 31 passes upward through the first sealing plate 18 and communicates with the interior of the cooling cylinder 33. The side wall of the straight pipe 31 is sealed to the first sealing plate 18. The cooling cylinder 33 is in communication with cooling water. A second sealing plate 19 is provided between the cooling cylinder 33 and the top cover 11. The top end of the steam pipe 36 passes upward through the second sealing plate 19 and communicates with the steam outlet of the top cover 11. The bottom end of the steam pipe 36 extends downward into the interior of the straight pipe 31, providing a steam passage for the steam generated by the evaporation of cooling water.

[0072] The first sealing plate 18 has a through hole, which allows the straight pipe 31 to pass through while also sealing the side wall of the straight pipe 31. The second sealing plate 19 has a through hole, which allows the steam pipe 36 to pass through while also sealing the side wall of the steam pipe 36.

[0073] Furthermore, the cooling cylinder 33 can be disposed between the top cover 11 and the low-temperature section 12.

[0074] In other embodiments, the cooling pipe may be a U-shaped pipe 32, with both ends of the cooling pipe located at the top. One end is connected to cooling water, and the other end is a water outlet for discharging heated saturated condensate.

[0075] Based on the U-shaped tube 32 structure of the cooling pipe, the inlet cooling water of the cooling pipe can be changed to condensate. The condensate is pumped to the high-temperature section 13 and then exchanged with the reaction gas inside and outside the cooling pipe to remove heat. The saturated condensate comes out of the cooling pipe and is sent to a low-pressure tank for flash evaporation. The steam after flash evaporation is recovered to the steam network.

[0076] Optionally, the cooling pipe includes an inlet end and an outlet end. The inlet end is located below the high-temperature section 13 and is used to connect to the cooling water, while the outlet end is located above the high-temperature section 13. The cooling pipe between the inlet end and the outlet end can be arranged in a spiral structure, a U-shaped coil, or a multi-layer concentric coil structure, as long as sufficient heat absorption area is ensured. By placing the inlet end below and the outlet end above, steam discharge is more convenient. It should be noted that the cooling effect of the cooling pipe can be adjusted by regulating the flow rate and velocity at the inlet end.

[0077] When the cooling pipe is a U-shaped pipe 32 or a spiral structure, the stability of the suspended part of the cooling pipe and the connection between the cooling pipe and the inner wall of the furnace can also be improved by using the stabilizing component 34 and the supporting component.

[0078] In some embodiments, the low-temperature segment 12 is connected to the high-temperature segment 13 via the enlarged segment 15, wherein the low-temperature segment 12 has a larger diameter than the high-temperature segment 13, and the low-temperature segment 12 is smoothly connected to the high-temperature segment 13 via the enlarged segment 15.

[0079] The low-temperature section 12 provides a larger space, reducing the gas velocity of the gas-solid mixture. Solid particles settle under gravity, achieving gas-solid separation and reducing powder particle entrainment in the gas, thus improving separation efficiency. Typically, the cavity diameter of the low-temperature section 12 is 1.2 to 1.8 times that of the high-temperature section 13. The separated mixed gas exits through the outlet 163 on the top cover 11 and enters the gas-to-gas heat exchanger.

[0080] Continue to refer to Figure 1 and Figure 6 As shown, the first inlet 161 can be inclinedly arranged between the enlarged section 15 and the high-temperature section 13, specifically on the side wall of the cylinder of the high-temperature section 13. Silicon powder and high-pressure gas enter the interior of the high-temperature section 13 from the first inlet 161, and the inlet end of the first inlet 161 is higher than its outlet end.

[0081] Furthermore, a first pressure gauge 54 and a second pressure gauge 55 may be provided on the side wall of the high-temperature section 13, wherein the first pressure gauge 54 and the second pressure gauge 55 are respectively located below and above the heater 2.

[0082] The material level is controlled by the pressure difference between the first pressure gauge 54 at the bottom of the bed and the second pressure gauge 55 at the top of the bed. The higher the material level, the greater the resistance of gas passing through the bed, and the greater the pressure difference. The pressure difference signal is fed back to the feeding system to achieve stable material level control. Control logic: Set a target pressure difference (corresponding to the target material level). When the actual pressure difference > the target value (material level too high), reduce the feed rate or increase the venting rate; when the actual pressure difference < the target value (material level too high), increase the feed rate or decrease the venting rate.

[0083] Continue to refer to Figure 7 As shown, the specific operation procedure of the above-mentioned reactor can be as follows: Before operation, the air inside the furnace is replaced with nitrogen. Once the furnace is found to be oxygen-free, hot hydrogen gas at 140°C to 180°C is introduced through the third feed port 164 on the bottom cover 14, passing through the porous distribution plate 4 into the bed. Then, the power of the radiant heater 2 is turned on. The temperature of the furnace wall is observed through the external temperature measuring port 51 and the temperature inside the furnace is observed through the furnace thermometer 53 to confirm that the temperature is within the set reaction temperature range (280°C to 340°C), with a temperature accuracy control within ±5°C to 10°C. Silicon powder is then pushed in through the first feed port 161. After establishing a certain material level, the power of the radiant heater 2 is turned off.

[0084] Next, a certain flow rate of anhydrous hydrogen chloride gas (50°C~80°C) is introduced into the bottom cover section 14 through the second feed port 162, and then enters the high-temperature section 13 through the porous distribution plate 4 to carry out the synthesis reaction. The high-temperature trichlorosilane mixed gas produced by the reaction undergoes gas-to-gas heat exchange with the cold hydrogen gas from the compressor system. The preheated hydrogen gas is then returned to the hydrogen inlet pipeline of the synthesis furnace for recycling. The cooled trichlorosilane mixed gas is then subjected to dust removal, condensation, and distillation to finally obtain high-purity products trichlorosilane and silicon tetrachloride. The hydrogen gas produced in the reaction is returned to the gas-to-gas heat exchanger by the hydrogen compressor for recycling, and the excess hydrogen gas is recovered to the pipeline network.

[0085] The specific implementation method and principle are the same as those in the above embodiments, and can bring the same or similar technical effects. They will not be repeated here. For details, please refer to the description of the above reactor embodiments.

[0086] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0087] The above description is merely a specific embodiment of this application, enabling those skilled in the art to understand or implement this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments described herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A reactor, characterized in that, include: The furnace body includes, from top to bottom, a top cover, a low-temperature section, a high-temperature section and a bottom cover in the vertical direction. The top of the low-temperature section has a discharge port, the top of the high-temperature section has a first inlet port, the outer wall of the high-temperature section is equipped with a heater, the side of the bottom cover has a second inlet port, and the bottom surface of the bottom cover has a third inlet port. A cooling device includes a cooling pipe, at least a portion of which extends into the inner side of the high-temperature section, and cooling water flows through the cooling pipe. A distribution plate is disposed between the high-temperature section and the bottom cover. The distribution plate has a material passage hole for connecting the high-temperature section and the bottom cover.

2. The reactor according to claim 1, characterized in that, The heater is fitted onto the outer wall of the high-temperature section and is used to heat the outer wall of the high-temperature section.

3. The reactor according to claim 2, characterized in that, The heater has an annular heating surface that is in contact with the outer wall of the high-temperature section.

4. The reactor according to claim 2, characterized in that, The heater is provided with an outer wall temperature measuring port that extends to the outer wall of the high-temperature section.

5. The reactor according to claim 4, characterized in that, The outer wall temperature measuring ports are arranged in multiple ways along the height direction.

6. The reactor according to claim 1, characterized in that, The bottom cover is equipped with a feed thermometer, which is used to detect the temperature of the material entering from the second feed port.

7. The reactor according to claim 1, characterized in that, The furnace body is equipped with an in-furnace thermometer, which extends along the height direction and has multiple temperature measuring points in the vertical direction, with at least two of the temperature measuring points located inside the high-temperature section.

8. The reactor according to claim 1, characterized in that, A buffer slot is provided on the top surface of the distribution plate, and all the material passage holes are connected to the buffer slot.

9. The reactor according to claim 1, characterized in that, The distribution plate is a concave plate that arches downwards from the center.

10. The reactor according to any one of claims 1-9, characterized in that, The cooling pipe includes a straight pipe extending vertically, the bottom end of which extends into the inner side of the high-temperature section, the top end of which is connected to cooling water, and the top end of which has a steam outlet connected to the outside.

11. The reactor according to claim 10, characterized in that, A steam pipe is fitted inside the straight pipe, and a space for accommodating cooling water is formed between the steam pipe and the straight pipe. The bottom end of the steam pipe and the bottom end of the straight pipe have a channel for steam to pass through, and the top end of the steam pipe is connected to the steam outlet.

12. The reactor according to claim 10, characterized in that, The bottom end of the straight tube is provided with a guide block, the bottom of which has a pointed tip, and the pointed tip smoothly transitions to the side wall of the straight tube through a plane or an arc surface.

13. The reactor according to claim 10, characterized in that, The cooling device also includes a stabilizing component, with multiple straight pipes arranged inside the furnace body, and at least two straight pipes connected through the stabilizing component.

14. The reactor according to claim 13, characterized in that, The stabilizing components are arranged in multiple vertical directions.

15. The reactor according to claim 13, characterized in that, The cooling device further includes a support assembly, which includes a support member having a first support end and a second support end. The first support end abuts against the side wall of the furnace body, the second support end abuts against the stabilizing component, and the support is horizontally disposed between the side wall of the furnace body and the stabilizing component.

16. The reactor according to claim 10, characterized in that, The cooling device also includes a cooling cylinder disposed on the top of the furnace body. A first sealing plate is provided between the cooling cylinder and the top cover. The top end of the straight pipe passes upward through the first sealing plate and communicates with the interior of the cooling cylinder. The side wall of the straight pipe is sealed to the first sealing plate. The cooling cylinder is in communication with cooling water. A steam outlet is provided at the top of the cooling cylinder.

17. The reactor according to any one of claims 1-9, characterized in that, The cooling pipe includes an inlet end and an outlet end. The inlet end is located below the high-temperature section and is used to connect cooling water, while the outlet end is located above the high-temperature section.

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