A self-regulating nozzle device and a polysilicon reduction furnace system

Abstract

The application discloses a self-adjusting nozzle device and a polysilicon reduction furnace system. The self-adjusting nozzle device comprises a shell and a core. The shell is provided with an inner cavity, an air inlet and a nozzle, and the inner cavity is located between the air inlet and the nozzle and communicates with the air inlet and the nozzle at both ends. The core is accommodated in the inner cavity, and the core comprises a first core part and a second core part. A first cavity is sealingly arranged between the outer side wall of the first core part and the inner side wall of the inner cavity, and the first core part is connected with the inner side wall of the inner cavity through a first elastic member. A second cavity is sealingly arranged between the outer side wall of the second core part and the inner side wall of the inner cavity, and the second core part is connected with the inner side wall of the inner cavity through a second elastic member. An air inlet channel is formed between the first core part and the second core part, and the air inlet channel is used for allowing raw material gas to pass through. When the raw material gas passes through, the first elastic member and the second elastic member adjust the spacing between the first core part and the second core part. Therefore, the device can improve the flow field uniformity in the reduction furnace.

Description

Technical Field

[0001] The present invention specifically relates to a self-adjusting nozzle device and a polycrystalline silicon reduction furnace system. Background Technology

[0002] Over the past few decades, the solar energy industry has been developing rapidly. Polycrystalline silicon is one of the raw materials for solar cell production, making the polycrystalline silicon reduction furnace an indispensable piece of equipment in solar cell production. Traditional polycrystalline silicon production mainly uses the modified Siemens process, which involves introducing a mixture of trichlorosilane and hydrogen in a specific ratio for a high-temperature vapor-phase chemical deposition reaction. The resulting free silicon deposits on an electrically heated silicon core and gradually grows to form the existing polycrystalline silicon products.

[0003] However, traditional polysilicon reduction furnaces primarily employ a design with bottom-mounted nozzles for gas inlet and exhaust outlets for gas outlet, creating a flowing temperature and gas field within the furnace. During the reaction, the feed rate needs to be adjusted according to the furnace conditions to avoid problems such as poor polysilicon morphology and high power consumption. Traditional polysilicon reduction furnace nozzles typically consist of fixed nozzles and a control system. When the feed rate increases during the reaction, the nozzle size may not be sufficient to meet the current flow rate and pressure, leading to an uneven flow field within the reduction furnace, resulting in poor silicon rod morphology and safety hazards. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to address the above-mentioned deficiencies in the prior art by providing a self-adjusting nozzle device and a polycrystalline silicon reduction furnace system, wherein the self-adjusting nozzle device can effectively improve the uniformity of the flow field in the reduction furnace.

[0005] According to a first aspect of the present invention, a self-adjusting nozzle device is provided, comprising: a housing and a core. The housing has an inner cavity, an air inlet at one end and a nozzle at the other end, the inner cavity being located between the air inlet and the nozzle, the two ends of the inner cavity communicating with the air inlet and the nozzle respectively, the central axes of the air inlet, the nozzle, and the inner cavity all extending along a first axis direction, the core being housed within the inner cavity, the shape of the core being adapted to the shape of the inner cavity, the core comprising a first core portion and a second core portion, the first core portion and the second core portion being disposed opposite to each other, a first cavity being sealed between the outer side wall of the first core portion and the inner side wall of the inner cavity. The cavity contains a first elastic element, and a first core is connected to the inner wall of the cavity through the first elastic element. A second cavity is sealed between the outer wall of the second core and the inner wall of the cavity. The second cavity contains a second elastic element, and the second core is connected to the inner wall of the cavity through the second elastic element. An air intake channel is formed between the first core and the second core. The two ends of the air intake channel are respectively connected to the air inlet and the nozzle. The air intake channel is used to allow raw material gas to pass through. When the raw material gas passes through, the first elastic element and the second elastic element adjust the distance between the first core and the second core.

[0006] Preferably, the central axes of the first elastic element and the second elastic element both extend along the direction of the second axis, and the direction of the second axis is orthogonal to the direction of the first axis.

[0007] Preferably, both the first elastic element and the second elastic element are compression springs.

[0008] Preferably, the device further includes a first sealing ring and a second sealing ring, the central axes of which both extend along the second axis. The first sealing ring is located between the outer wall of the first core and the inner wall of the inner cavity, and the outer wall of the first core presses the first sealing ring against the inner wall of the inner cavity, thereby forming a sealed first cavity between the outer wall of the first core and the inner wall of the inner cavity. The second sealing ring is located between the outer wall of the second core and the inner wall of the inner cavity, and the outer wall of the second core presses the second sealing ring against the inner wall of the inner cavity, thereby forming a sealed second cavity between the outer wall of the second core and the inner wall of the inner cavity.

[0009] Preferably, both the first sealing ring and the second sealing ring are made of elastic material.

[0010] Preferably, the device further includes a first guide member and a second guide member, which are respectively located in the first cavity and the second cavity. A first guide groove is provided on the outer side of the first core, which extends along the second axis. The first guide member corresponds to the first guide groove. One end of the first guide member is connected to the side wall of the inner cavity, and the other end is inserted into the first guide groove to guide the first core. A second guide groove is provided on the outer side of the second core, which extends along the second axis. The second guide member corresponds to the second guide groove. One end of the second guide member is connected to the side wall of the inner cavity, and the other end is inserted into the second guide groove to guide the second core.

[0011] Preferably, the inner cavity has a circular cross-section in the horizontal direction, the first core and the second core have semi-circular cross-sections in the horizontal direction, and the opposite ends of the first core and the second core are planar.

[0012] Preferably, the inner cavity is spherical, the first core and the second core are hemispherical, the planar ends of the first core and the second core are disposed opposite each other, and the radii of the first core and the second core are smaller than the radius of the inner cavity.

[0013] Preferably, the planar end of the first core is provided with a first arc-shaped surface that is recessed inward, and the first arc-shaped surface extends along the first axis. The planar end of the second core is provided with a second arc-shaped surface that is recessed inward, and the second arc-shaped surface extends along the first axis. The first arc-shaped surface and the second arc-shaped surface are arranged opposite to each other.

[0014] According to an embodiment of a second aspect of the present invention, a polysilicon reduction furnace system is provided, comprising a reduction furnace, an inlet branch pipe, and a self-adjusting nozzle device as described in the first aspect embodiment. The self-adjusting nozzle device is mounted on the chassis of the reduction furnace, the nozzle of the self-adjusting nozzle device is connected to the inner cavity of the reduction furnace, the inlet is connected to the inlet branch pipe, and the inlet branch pipe delivers raw material gas into the furnace cavity of the reduction furnace through the self-adjusting nozzle device.

[0015] Preferably, the intake branch pipe is provided with a regulating valve, which is used to regulate the flow rate of the raw material gas in the intake branch pipe.

[0016] The self-adjusting nozzle device of this invention improves the uniformity of the flow field within the reduction furnace by incorporating elastic elements between the two hemispherical cores and the sidewalls of the inner cavity. This is achieved by adjusting the distance between the first and second cores according to changes in the feed gas flow rate. Specifically, the feed gas enters the nozzle's intake channel through the inlet. As the feed gas flow rate increases, the radial pressure exerted by the feed gas on the nozzle cores (i.e., the first and second cores) increases, causing the first and second cores to separate to the sides, moving towards the sidewalls of the first cavity. Based on Hooke's law of springs, it is easy to understand that the first and second elastic elements are continuously compressed until the pressure and elastic force generated by the feed gas reach equilibrium again. The increased radius of the intake channel (i.e., the increased distance between the first and second cores) increases the flow space through which the feed gas can pass. As the cross-sectional area of ​​the intake channel increases, the feed gas velocity decreases, ensuring that the feed gas ejected from the nozzle does not disrupt the flow field within the reduction furnace. Furthermore, when the flow rate of the raw material gas decreases or stops, the pressure exerted by the raw material gas on the nozzle core (i.e., the first core and the second core) in the air intake channel decreases accordingly, and the elastic force of the elastic element is greater than the pressure of the raw material gas. At this time, the elastic potential energy generated by the compression of the springs (the first and second elastic elements) is released, pushing the first and second cores of the nozzle core to move towards each other, that is, towards the direction closer to the central axis of the air intake channel. Based on Hooke's law of springs, it can be known that the elastic element continues to stretch to the initial state until the pressure and elastic force reach equilibrium again, the radius of the air intake channel decreases, and the passable flow space decreases to the initial state. As the cross-sectional area of ​​the air intake channel decreases, the flow velocity of the raw material gas increases, making the flow velocity of the raw material gas uniform, thereby reducing the disturbance of the flow channel in the reduction furnace. In summary, this self-adjusting nozzle device can effectively improve the uniformity of the flow field in the reduction furnace. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of the self-adjusting nozzle device in some embodiments of the present invention;

[0018] Figure 2 This is a structural schematic diagram of the cross-section of a self-adjusting nozzle device in some embodiments of the present invention.

[0019] In the figure: 1-shell, 21-first sealing ring, 22-second sealing ring, 3-core, 31-first core, 32-second core, 41-first elastic element, 42-second elastic element, 5-screw, 6-third sealing ring, 7-nozzle bottom movable part, 71-air inlet, 8-first guide, 9-nozzle movable part, 91-nozzle, 101-first cavity, 102-second cavity, 11-first groove, 111-first circumferential groove, 112-second circumferential groove, 12-second groove, 13-air inlet channel, 14-first axial direction, 15-second axial direction. Detailed Implementation

[0020] The technical solutions of the invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the invention, not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without creative effort are within the scope of the invention.

[0021] In the description of this invention, it should be noted that the terms "upper", "lower", "upstream", "downstream", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience and simplification of the description and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0022] In the description of this invention, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0023] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "connection," "setting," "installation," "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0024] Example 1

[0025] Please see Figure 1 The present invention discloses a self-adjusting nozzle device, comprising: a housing 1 and a core 3.

[0026] The shell 1 has an internal cavity. One end of the shell 1 has an air inlet 71, and the other end has a nozzle 91. The internal cavity is located between the air inlet 71 and the nozzle 91, and its two ends are connected to the air inlet 71 and the nozzle, respectively. The central axes of the air inlet 71, the nozzle 91, and the internal cavity all extend along the first axis direction 14. It should be noted that by keeping the central axes of the air inlet 71, the nozzle 91, the internal cavity, and the shell 1 on the same extended line, the resistance loss encountered by the gas during flow can be reduced, the gas flow efficiency can be improved, and the uniformity of the flow field can be maintained, avoiding unevenness in gas flow, which is beneficial to the reaction in the reduction furnace and the uniform generation of products.

[0027] Furthermore, the core 3 is housed within the inner cavity, and the shape of the core 3 is adapted to the shape of the inner cavity. The core 3 includes a first core portion 31 and a second core portion 32, which are disposed opposite to each other. A first cavity 101 is sealed between the outer wall of the first core portion 31 and the inner wall of the inner cavity. A first elastic member 41 is placed inside the first cavity 101, and the first core portion 31 is connected to the inner wall of the inner cavity through the first elastic member 41. A second cavity 102 is sealed between the outer wall of the second core portion 32 and the inner wall of the inner cavity. A second elastic member 42 is placed inside the second cavity 102, and the second core portion 32 is connected to the inner wall of the inner cavity through the second elastic member 42. An air intake channel 13 is formed between the first core 31 and the second core 32. The two ends of the air intake channel 13 are connected to the air inlet 71 and the nozzle 91, respectively. The air intake channel 13 is used to supply raw material gas. When the raw material gas passes through, the first elastic member 41 and the second elastic member 42 adjust the distance between the first core 31 and the second core 32.

[0028] It should be noted that the central axes of both the first elastic element 41 and the second elastic element 42 extend along the second axis direction 15, which is orthogonal to the first axis direction 14. Specifically, the first axis direction 14 is... Figure 1 The vertical direction in the middle, the direction of the second axis 15 is... Figure 1 The first elastic element 41 can provide elastic force to the first core 31 in the direction of the second axis, and the second elastic element 42 can provide elastic force to the second core 32 in the direction of the second axis.

[0029] Preferably, both the first elastic element 41 and the second elastic element 42 are compression springs. Specifically, the compression spring is mainly used to provide elastic force in its axial direction to store or release elastic potential energy, thereby enabling automatic adjustment of the gap between the first core 31 and the second core 32.

[0030] Furthermore, such as Figure 1As shown, the device also includes a first guide member 8 and a second guide member (not shown in the figure, but it is easy to understand that the second guide member is symmetrically arranged with the first guide member 8). The first guide member 8 and the second guide member are located in the first cavity 101 and the second cavity 102, respectively. A first guide groove is provided on the outer side of the first core 31, extending along the second axis. The first guide member 8 corresponds to the first guide groove. One end of the first guide member 8 is connected to the side wall of the inner cavity, and the other end is inserted into the first guide groove to guide the first core 31. A second guide groove is provided on the outer side of the second core 32, extending along the second axis. A second guide member corresponds to the second guide groove. One end of the second guide member is connected to the side wall of the inner cavity, and the other end is inserted into the second guide groove to guide the second core 32. By providing guide members, the downward displacement of the first core 31 and the second core 32 under the action of gravity can be avoided.

[0031] In this embodiment, the raw material gas refers to a mixture of trichlorosilane and hydrogen. The raw material gas enters the intake channel 13 in the nozzle through the intake port 71. As the flow rate of the raw material gas increases, the radial pressure exerted by the raw material gas in the intake channel 13 on the nozzle core 3 (i.e., the first core 31 and the second core 32) increases accordingly, causing the first core 31 and the second core 32 to separate to both sides, that is, to move towards the side walls of the first cavity 101. Based on Hooke's law of springs, it is easy to understand that at this time, the first elastic element 41 and the second elastic element 42 are continuously compressed until the pressure and elastic force generated by the raw material gas reach equilibrium again. The increase in the radius of the intake channel 13 (i.e., the increase in the distance between the first core 31 and the second core 32) increases the flow space through which the raw material gas can pass. As the cross-sectional area of ​​the intake channel 13 increases, the flow rate of the raw material gas decreases, thereby ensuring that the raw material gas ejected from the nozzle 91 does not disturb the flow field inside the reduction furnace.

[0032] Furthermore, when the flow rate of the raw material gas decreases or stops, the pressure exerted by the raw material gas on the nozzle core 3 (i.e., the first core 31 and the second core 32) in the air intake channel 13 decreases accordingly, and the elastic force of the elastic element is greater than the pressure of the raw material gas. At this time, the elastic potential energy generated by the compression of the spring (the first elastic element 41 and the second elastic element 42) is released, pushing the first core 31 and the second core 32 of the nozzle core 3 to move towards each other, that is, to move towards the central axis of the air intake channel 13. Based on Hooke's law of springs, it can be known that the elastic element continues to stretch to the initial state until the pressure and elastic force reach equilibrium again, the radius of the air intake channel 13 decreases, and the flow space that can pass through is reduced to the initial state. As the cross-sectional area of ​​the air intake channel 13 decreases, the flow rate of the raw material gas increases, making the flow rate of the raw material gas uniform, thereby reducing the disturbance of the flow channel in the reduction furnace.

[0033] Therefore, this self-adjusting nozzle device can effectively improve the uniformity of the flow field in the reduction furnace.

[0034] In this embodiment, the housing 1 of the self-adjusting nozzle device is cylindrical, and the central axis of the housing 1 and the central axis of the internal cavity are both located in the direction of the first axis. For example... Figure 1 As shown, the direction of the first axis is the direction of the vertical axis.

[0035] Furthermore, such as Figure 2 As shown, the cross-section of the inner cavity in the horizontal direction is circular, and the cross-section of the first core 31 and the second core 32 in the horizontal direction is semi-circular. The opposite ends of the first core 31 and the second core 32 are planar. Moreover, the radius of the first core 31 and the second core 32 is smaller than the radius of the inner cavity. The two cores have the same structure and are arranged opposite each other. The advantage of this arrangement is that when the raw material gas enters the air intake channel 13 in the nozzle through the air inlet 71, the pressure exerted by the raw material gas on the two cores is basically the same, and the situation where one core is subjected to greater pressure, resulting in severe wear of the elastic element on one side, is avoided. Furthermore, by setting the cross-section of the inner cavity and the nozzle core 3 (the first core 31 and the second core 32) to be circular, the shape of the inner cavity and the core 3 can be adapted to each other, and the distance between the outer surface of the core 3 and the inner wall of the inner cavity is the same, which can avoid collision between the nozzle core 3 and the inner wall of the inner cavity.

[0036] For example, the inner cavity can be cylindrical or spherical; correspondingly, the first core 31 and the second core 32 can be semi-cylindrical or hemispherical, as long as the shape of the core 3 can be adapted to the shape of the inner cavity.

[0037] In this embodiment, the device further includes a first sealing ring 21 and a second sealing ring 22. A first cavity 101 is provided between the outer side wall and the inner side wall of the first core 31, and the first cavity 101 is sealed by the first sealing ring 21; a second cavity 102 is provided between the outer side wall and the inner side wall of the second core 32, and the second cavity 102 is sealed by the second sealing ring 22.

[0038] It is worth noting that in this embodiment, both the first cavity 101 and the second cavity 102 need to be kept sealed to maintain the initial gas pressure P0. This is crucial for improving the flow field uniformity of this nozzle device. The reason is that if the first cavity 101 and the second cavity 102 cannot be kept sealed, that is, if the raw material gas enters the first cavity 101 and the second cavity 102 during the raw material gas intake process, the gas pressure in the intake channel 13, the first cavity 101, and the second cavity 102 will change synchronously (increasing or decreasing simultaneously). Therefore, regardless of whether the flow rate of the raw material gas increases or decreases, the gas pressure in the intake channel 13 will remain consistent with the gas pressure in the first cavity 101 and the second cavity 102. No pressure difference can be generated between the intake channel 13 and the first cavity 101 and the second cavity 102, thus preventing pressure from being applied to the first elastic element 41 or the second elastic element 42, causing the self-adjusting nozzle device to fail.

[0039] Furthermore, such as Figure 1 As shown, the central axes of both the first sealing ring 21 and the second sealing ring 22 extend along the direction of the second axis. In other words, both the first sealing ring 21 and the second sealing ring 22 are annular, and their circumferential directions are both on a vertical plane. The first sealing ring 21 is located between the outer wall of the first core 31 and the inner wall of the inner cavity. The outer wall of the first core 31 presses the first sealing ring 21 against the inner wall of the inner cavity, thereby forming a sealed first cavity 101 between the outer wall of the first core 31 and the inner wall of the inner cavity. The second sealing ring 22 is located between the outer wall of the second core 32 and the inner wall of the inner cavity. The outer wall of the second core 32 presses the second sealing ring 22 against the inner wall of the inner cavity, thereby forming a sealed second cavity 102 between the outer wall of the second core 32 and the inner wall of the inner cavity.

[0040] In this embodiment, the inner cavity is spherical, and the first core 31 and the second core 32 are hemispherical, with their planar ends facing each other. By using a spherical inner cavity and two symmetrical hemispheres as the first core 31 and the second core 32, the first core 31 and the second core 32 can cooperate with the first sealing ring 21 and the second sealing ring 22 to better achieve the sealing of the first cavity 101 and the second cavity 102.

[0041] Specifically, a first groove 11 is provided in the spherical inner cavity. The first groove 11 includes a first circumferential groove 111 and a second circumferential groove 112. The two circumferential grooves are arranged opposite each other along the second axis, and the circumferential planes of the two circumferential grooves are both on vertical planes. The first circumferential groove 111 is located on the side closer to the first core 31, and the first sealing ring 21 is engaged in the first circumferential groove 111. The second circumferential groove 112 is located on the side closer to the second core 32, and the second sealing ring 22 is engaged in the second circumferential groove 112. Under the elastic force of the first elastic member 41, the outer wall of the first core 31 presses the first sealing ring 21 into the first circumferential groove 111, so that a sealed first cavity 101 is formed between the outer wall of the first core 31 and the inner wall of the inner cavity. Under the elastic force of the second elastic member 42, the outer wall of the second core 32 presses the second sealing ring 22 into the second circumferential groove 112, so that a sealed second cavity 102 is formed between the outer wall of the second core 32 and the inner wall of the inner cavity.

[0042] It should be noted that by using a spherical inner cavity and hemispherical first core 31 and second core 32, the shape of the vertical cross section of the inner cavity and nozzle core 3 is also circular, which can better match the first sealing ring 21 and the second sealing ring 22.

[0043] The following will further explain the fit and working principle between the nozzle core 3, the inner cavity, and the sealing ring.

[0044] The first sealing ring 21 is located between the outer wall of the first core 31 and the inner wall of the inner cavity. The outer wall of the first core 31, the inner wall of the inner cavity, and the first sealing ring 21 form a first cavity 101. The first cavity 101 is in a sealed state, therefore, an initial air pressure P0 is always maintained therein. This initial air pressure can be one atmosphere. Similarly, the outer wall of the second core 32, the inner wall of the inner cavity, and the second sealing ring 22 form a second cavity 102, which also maintains an initial air pressure P0. An air intake channel 13 is formed between the first core 31 and the second core 32. The air pressure P in the air intake channel 13 changes with the air intake flow rate, while the pressure between the first cavity 101 and the second cavity 102 remains constant.

[0045] When no raw material gas is introduced, the gas pressure P in the air inlet channel 13 is balanced with the initial gas pressure P0. At this time, the elastic elements in the first cavity 101 and the second cavity 102 are in the initial state.

[0046] As the flow rate of the raw material gas increases, the radial pressure (i.e., gas pressure P) exerted by the raw material gas in the intake channel 13 on the nozzle core 3 (i.e., the first core 31 and the second core 32) increases accordingly until the pressure difference (P-P0) between the raw material gas pressure P and the initial gas pressure P0 is greater than the elastic force of the elastic element. At this point, the first core 31 and the second core 32 move to the left and right sides respectively under the action of radial pressure pointing to the left and right sides. Subsequently, the first elastic element 41 and the second elastic element 42 are deformed under pressure and generate elastic potential energy. This continues until the pressure difference between the raw material gas pressure P and the initial gas pressure P0 and the elastic force of the elastic element reach equilibrium again. It is easy to understand that when the first core 31 and the second core 32 separate to the sides, the cross-section of the air inlet channel 13 increases. According to the continuity equation of flow velocity (A1v1=A2v2, where A is the area and v is the flow velocity of the fluid), it can be known that when the pipe diameter (i.e. the cross-sectional area of ​​the air inlet channel 13) increases, the gas flow velocity will decrease accordingly, which will slow down the flow velocity of the raw material gas ejected from the nozzle 91 and will not disturb the flow field in the reduction furnace.

[0047] When the flow rate of the raw material gas decreases, the radial pressure (i.e., gas pressure P) exerted by the raw material gas in the inlet channel 13 on the nozzle core 3 (i.e., the first core 31 and the second core 32) decreases accordingly. At this time, the pressure difference (P-P0) between the gas pressure P and the initial gas pressure P0 is less than the elastic force of the elastic element, that is, the balance between the pressure difference and the elastic force is broken, and the elastic element rebounds. If the flow rate of the raw material gas decreases to 0, i.e., the feeding stops, the elastic element will rebound to the initial state. Similarly, when the first core 31 and the second core 32 move closer to the center, the cross-section of the inlet channel 13 decreases. According to the continuity equation of flow velocity, the gas velocity in the inlet channel 13 will increase accordingly, thereby ensuring that the flow velocity of the raw material gas ejected from the nozzle 91 remains at a small fluctuation, further avoiding disturbance of the flow field in the reduction furnace.

[0048] It should also be noted that since the first core 31 and the second core 32 will move to the left and right, the first sealing ring 21 and the second sealing ring 22 will inevitably be compressed. Therefore, both the first sealing ring 21 and the second sealing ring 22 are made of elastic material to avoid damage under pressure. It should also be noted that in a polycrystalline silicon reduction furnace, the reaction temperature of the raw material gas can reach thousands of degrees Celsius. At this high temperature, to prevent thermal deformation and damage to the sealing rings, the first sealing ring 21 and the second sealing ring 22 need to be made of high-temperature resistant materials. Preferably, both the first sealing ring 21 and the second sealing ring 22 can be made of ceramic fiber materials, aluminosilicate fiber materials, etc. Taking aluminosilicate fiber material as an example, aluminosilicate fiber material is a lightweight refractory material with advantages such as high temperature resistance, good thermal stability, and good elasticity, and can be used as a sealing ring material in high-temperature environments.

[0049] Please see Figure 1 and Figure 2 In this embodiment, the planar end of the first core 31 is provided with a first arc-shaped surface that is recessed inward and extends along the first axis. The planar end of the second core 32 is provided with a second arc-shaped surface that is recessed inward and extends along the first axis. The first and second arc-shaped surfaces are arranged opposite to each other. The first and second arc-shaped surfaces can be combined to form a cylindrical channel that extends vertically and penetrates the core 3. This cylindrical channel can be understood as part of the air intake channel 13. By providing this cylindrical channel, when the opposing planes of the first core 31 and the second core 32 are in contact, the raw material gas can also pass through the cylindrical channel, avoiding the situation where the first core 31 and the second core 32 completely block the air intake channel 13.

[0050] Furthermore, by setting the first arc-shaped surface and the second arc-shaped surface, the contact area between the raw material gas and the planar end of the first core 31 (or the second core 32) can be increased, thereby improving the influence of the flow rate change of the raw material gas on the radial pressure.

[0051] Please see Figure 1 and Figure 2 The following will describe other aspects of this self-adjusting nozzle device.

[0052] This self-adjusting nozzle device is a self-adjusting nozzle used in the reduction furnace of polycrystalline silicon production. It includes a nozzle core 3, a nozzle housing 1, a bottom movable part 7, and an orifice movable part 9. The nozzle housing 1 includes a first cavity 101 and a second cavity 102. A raw material gas inlet 71 is provided at the bottom, and a raw material gas outlet 91 is provided at the top. The cavity formed between the nozzle housing 1 and the nozzle core 3 is the first cavity 101 (or the second cavity 102) to ensure that the nozzle core 3 can move normally within the inner cavity. More specifically, the cavity formed between the inner cavity of the housing 1 and the first core 31 and the first sealing ring 21 is the first cavity 101, and the cavity formed between the inner cavity of the housing 1 and the second core 32 and the second sealing ring 22 is the second cavity 102.

[0053] The nozzle core 3 is configured with two hemispherical devices forming an air inlet channel 13. The lower end of the air inlet channel 13 (i.e., the bottom of the nozzle core 3) is connected to the air inlet 71 at the lower end of the nozzle housing 1, and then connected to the raw material gas inlet pipe on the reduction furnace chassis. The upper end of the air inlet channel 13 is connected to the raw material gas nozzle 91 at the top of the nozzle housing 1, forming the entire gas passage. The center lines of the air inlet channel 13 formed in the nozzle core 3 coincide with the center lines of the nozzle 91 and the raw material gas inlet (i.e., the air inlet 71) at the bottom of the housing 1.

[0054] To prevent the raw material gas in the first intake channel 13 from entering the first cavity 101 and the second cavity 102 through the gap between the contact wall of the nozzle core 3 and the nozzle housing 1, and to ensure a pressure difference between the first intake channel 13 and the first cavity 101, a first sealing ring 21 and a second sealing ring 22 are provided. The first sealing ring 21 is disposed between the first core 31 of the nozzle core 3 and the right side wall of the nozzle housing 1, and the second sealing ring 22 is disposed between the second core 32 of the nozzle core 3 and the left side wall of the nozzle housing 1. The first sealing ring 21, the second sealing ring 22 and the nozzle core 3 are concentric circles (that is, the vertical cross-sections of the first sealing ring 21, the second sealing ring 22 and the nozzle core 3 are all circular, and the centers of the first sealing ring 21, the second sealing ring 22 and the aforementioned vertical cross-sections are all located in the direction of the second axis). Meanwhile, a first groove 11 (i.e., a first circumferential groove 111 and a second circumferential groove 112) is provided at the corresponding position of the nozzle housing 1, a first seal is provided in the first circumferential groove 111, and a second seal is provided in the second circumferential groove 112.

[0055] Furthermore, the raw material gas in the intake channel 13 applies a certain pressure to the nozzle core 3 (first core 31 and second core 32) in the radial direction along the first cavity 101 (or the second cavity 102). The nozzle core 3 bears and transmits the above pressure, and under the combined action of the above pressure and the elastic force of the compressible movable members (i.e., the aforementioned first elastic member 41 and second elastic member 42), the nozzle core 3 can move in the radial direction along the first cavity 101 (specifically, the first core 31 moves to the right and the second core 32 moves to the left).

[0056] Furthermore, the initial structural radius of the air inlet channel 13 (i.e., the radius of the cylindrical channel formed by the first and second arcuate surfaces when no raw material gas is introduced) is smaller than the radius of the nozzle 91. A circular notch can be provided on one side of the nozzle core 3 forming the air inlet channel 13 (i.e., the aforementioned planar end), allowing the air inlet channel 13 to have a cylindrical channel. When the nozzle core 3 moves radially along the first cavity 101, the radius of the air inlet channel 13 increases, and the space of the first cavity 101 (and the second cavity 102) decreases. The change in the radius of the air inlet channel 13 corresponds to the change in the flow rate of the raw material gas; that is, the radius of the air inlet channel 13 automatically adjusts with the change in the flow rate (pressure) of the raw material gas, thereby reducing the difference in flow rate between nozzle feeding cycles and ensuring that the nozzle has a large adjustment range while maintaining the overall flow field uniformity within the reduction furnace.

[0057] The aforementioned compressible movable parts (i.e., the first elastic element 41 and the second elastic element 42) are fixed to the nozzle housing 1 by bolt connection and connected to the nozzle core 3. Utilizing Hooke's Law, the compressible movable parts can apply an elastic force to the nozzle body in the radial direction of the first cavity 101, so that when the flow rate of raw material gas in the first air intake channel 13 decreases or stops, the nozzle core 3 moves in the radial direction of the central axis, reducing the radius of the air intake channel 13.

[0058] The nozzle housing 1 is provided with a nozzle core 3 moving auxiliary component (i.e. the aforementioned first guide 8 and second guide). The first guide 8 and the second guide are fixed to the inner side wall of the nozzle housing 1 by threaded connection or welding, and are respectively located in the first cavity 101 and the second cavity 102, and are connected to the nozzle core 3 through the front end protrusion (specifically inserted into the guide groove of the core 3) to ensure the direction and position of the nozzle core 3 when moving.

[0059] Furthermore, the nozzle bottom movable part 7 is located at the bottom of the nozzle housing 1, connecting the air intake channel 13 and the chassis air intake pipe. Specifically, the air inlet 71 at the bottom of the housing 1 has internal threads, and the outer circumference of the nozzle bottom movable part 7 has external threads, connecting the nozzle bottom movable part 7 to the internal threads around the air inlet 71. This self-adjusting nozzle device is threadedly connected to the inlet of the air intake branch pipe via the nozzle bottom movable part 7. In addition, the nozzle port movable part 9 is located at the upper part of the nozzle housing 1, connecting the air intake channel 13 to the nozzle port 91. The nozzle port 91 at the upper end of the housing 1 has a tapered portion. The nozzle bottom movable part 7 and the nozzle port movable part 9 are detachable parts, connected to the nozzle housing 1 by threads, allowing for modification and replacement of their diameter and height as needed.

[0060] In some embodiments, such as Figure 1 As shown, the nozzle housing 1 is divided into upper and lower parts for easy installation of the entire nozzle. A recessed screw 5 connects the upper and lower parts via threads. To prevent raw material gas from entering the first chamber 101, a third sealing ring 6 is provided.

[0061] like Figure 2 As shown, to facilitate the installation of the third sealing ring 6, a second groove 12 is provided on the nozzle housing 1 at a position corresponding to the third sealing ring 6. The second groove 12 and the nozzle housing 1 are arranged concentrically, and the circumferential direction of the second groove 12 is on a horizontal plane. The third sealing ring 6 is disposed in the second groove 12.

[0062] The procedure for using this self-adjusting nozzle device is explained below:

[0063] The air inlet channel 13 inside the nozzle core 3 is connected to the raw material air inlet branch pipe of the reduction furnace chassis. The upper end of the air inlet channel 13 is connected to the nozzle 91, which allows the raw material gas to enter the air inlet channel 13 through the air inlet branch pipe and reach the nozzle 91, and then be ejected through the nozzle 91. The nozzle includes a nozzle housing 1 and a movable nozzle core 3 disposed inside the nozzle housing 1. The movable nozzle core 3 is in the form of two hemispherical devices (i.e., the first core 31 and the second core 32). The air inlet channel 13 is formed in the middle of the two hemispherical devices. The air inlet channel 13 can move in the radial direction of the first cavity 101. The raw material gas at the air inlet channel 13 can apply a certain pressure to the nozzle core 3. The nozzle core 3 is used to bear and transmit the pressure of the raw material gas. When the pressure is greater than the elastic force applied to the nozzle core 3 by the compressible movable part, the nozzle core 3 can move in the radial direction of the movable auxiliary part by utilizing the principle of internal and external pressure difference, and compress the compressible movable part until the pressure and the elastic force are balanced, thereby adjusting the radius of the air inlet channel 13.

[0064] When the flow rate of the raw material gas increases, the pressure exerted by the raw material gas on the nozzle core 3 in the intake channel 13 increases accordingly. The nozzle core 3 continues to move along the direction of the first cavity 101. Utilizing Hooke's law of springs, the compressible moving part is continuously compressed until the pressure and elastic force reach equilibrium again. The radius of the intake channel 13 increases, and the flow space that can pass through increases.

[0065] When the flow rate of the raw material gas decreases or stops feeding, the pressure (pressure difference) exerted by the raw material gas on the nozzle core 3 in the air intake channel 13 decreases to zero. The nozzle core 3 moves along the central axis of the air intake channel 13. Using Hooke's law of springs, the compressible moving part continues to extend to the initial state until the pressure and elastic force reach equilibrium again. The radius of the air intake channel 13 decreases, and the flow space that can pass through decreases to the initial state.

[0066] Therefore, the radius of the air inlet channel 13 in the nozzle core 3 is directly proportional to the flow rate of the raw material gas. That is, when the flow rate of the raw material gas changes, the pressure on the air inlet channel 13 also changes, and the radius of the air inlet channel 13 changes accordingly. This ensures that the reduction furnace nozzle has automatic adjustment capability, which is beneficial to improving the uniformity of the flow field in the early and late stages of the reduction furnace.

[0067] Furthermore, in actual production, the relationship between the inlet flow rate before and after the reduction furnace and the uniformity of the temperature field and flow field inside the furnace can be achieved by adjusting the initial radius dimensions of the inlet channel 13, the bottom movable part 7 of the nozzle and the nozzle movable part 9, as well as the bottom height of the nozzle, thereby meeting the actual production requirements and improving the quality of silicon rods.

[0068] In summary, in this embodiment, the self-adjusting nozzle device mainly uses the nozzle core 3 and the housing 1 structure to automatically adjust the size of the nozzle core 3 radially by means of the internal and external pressure difference, so that the overall radius size of the nozzle corresponds to the changes in the flow rate and pressure of the raw material gas, thereby making the internal flow reach a self-balancing state and making the flow field distribution in the reduction furnace more uniform.

[0069] The self-adjusting nozzle device rectifyes the feed gas by setting the nozzle movable part 9, so that the overall flow field will not be disordered; and the nozzle device is a movable part, which can replace the nozzle height and the final nozzle diameter according to the actual production needs.

[0070] In summary, this self-adjusting nozzle device has the following beneficial effects:

[0071] 1. This device, through the air inlet channel 13, nozzle 91, etc., can effectively solve the problem of poor uniformity of the front and rear temperature fields and flow fields in the reduction furnace during the polycrystalline silicon production process in the prior art, thereby reducing the increase of dense material in the later stage of silicon rod production and effectively reducing power consumption.

[0072] 2. By adding a nozzle core 3 and compressible movable parts (i.e., the first elastic part 41 and the second elastic part 42), the overall radius size of the nozzle corresponds to the changes in the flow rate and pressure of the raw gas, making the flow field distribution in the reduction furnace more uniform. At the same time, the nozzle radius size can be self-adjusted as the flow rate gradually increases according to the actual situation, so as to achieve self-adjustment of the uniformity of the reduction furnace.

[0073] 3. This device also includes a nozzle bottom movable part 7 and a nozzle port movable part 9. These parts are replaceable and can be replaced according to actual production needs to adjust the nozzle height and final nozzle diameter.

[0074] Example 2

[0075] Please see Figure 1 The present invention also discloses a polycrystalline silicon reduction furnace system, including a reduction furnace, an air inlet branch pipe and the self-adjusting nozzle device in Example 1.

[0076] The self-adjusting nozzle device is installed on the chassis of the reduction furnace. The nozzle of the self-adjusting nozzle device is connected to the inner cavity of the reduction furnace. The air inlet 71 is connected to the air inlet branch pipe. The air inlet branch pipe delivers raw material gas into the furnace cavity of the reduction furnace through the self-adjusting nozzle device.

[0077] Preferably, the gas inlet branch pipe of this polycrystalline silicon reduction furnace system is equipped with a regulating valve, which is used to regulate the flow rate of the raw material gas in the gas inlet branch pipe.

[0078] This polysilicon reduction furnace system is used for polysilicon production. Operators can adjust the flow rate of the raw material gas in the inlet branch pipe using a regulating valve, based on the conditions inside the furnace. Existing nozzle devices are mostly of fixed diameter, which cannot meet the requirement of maintaining a stable flow field inside the furnace when the raw material gas flow rate changes. Alternatively, the nozzle diameter needs to be manually adjusted, requiring adjustment of the nozzle diameter every time the inlet flow rate is adjusted, making the operation very cumbersome.

[0079] The polycrystalline silicon reduction furnace system in this embodiment adopts the self-adjusting nozzle device from Embodiment 1, which can automatically adjust the diameter of the air inlet channel 13 according to the air inlet flow rate, thereby effectively improving the uniformity of the flow field in the reduction furnace. In other words, the self-adjusting nozzle device, through the specific structure of the self-adjusting nozzle, achieves controllable size at the nozzle orifice under different flow rates, so that the nozzle effectively improves the uniformity of the distribution of various components in the furnace, thereby reducing problems such as loose, coral-like, and other non-dense deposits on the silicon rod, and safety hazards caused by pressure buildup.

[0080] Specifically, the nozzle core 3 of the self-adjusting nozzle device in Embodiment 1 includes an air inlet channel 13, which is connected to the raw material air inlet branch pipe of the reduction furnace chassis. The upper end of the air inlet channel 13 is connected to a nozzle, allowing the raw material gas to enter the air inlet channel 13 through the air inlet branch pipe and reach the nozzle, which then exits. The nozzle includes a nozzle housing 1 and a movable nozzle core 3 disposed inside the nozzle housing 1. The movable nozzle core 3 is in the form of two hemispherical devices, with the air inlet channel 13 formed in the middle. It moves radially along the moving auxiliary component. The raw material gas at the air inlet channel 13 can apply a certain pressure to the nozzle core 3. The nozzle core 3 is used to bear and transmit the pressure of the raw material gas. Utilizing the principle of internal and external pressure difference, under the action of the aforementioned pressure, the nozzle core 3 can move radially along the moving auxiliary component, thereby adjusting the radius of the air inlet channel 13. Furthermore, the change in the radius of the air inlet channel 13 corresponds to the change in the flow rate of the raw material gas. That is, the radius of the air inlet channel 13 is automatically adjusted according to the change in the air inlet pressure of the raw material gas. After the reaction is completed, the external pressure is reduced by the compressible moving part using Hooke's law of springs, and the spring returns to its initial extension position, so that the nozzle core 3 returns to its initial position. This ensures that the nozzle of the reduction furnace has an automatic adjustment capability, which is beneficial to improving the uniformity of the flow field in the early and late stages of the reduction furnace.

[0081] In summary, this polysilicon reduction furnace system can improve the uniformity of the flow field in the reduction furnace, thereby improving the production quality of polysilicon.

[0082] It is understood that the above embodiments are merely exemplary implementations used to illustrate the principles of the present invention, and the present invention is not limited thereto. For those skilled in the art, various modifications and improvements can be made without departing from the spirit and essence of the present invention, and these modifications and improvements are also considered to be within the scope of protection of the present invention.

Claims

1. A self-adjusting nozzle device, characterized in that, include: Shell (1) and core (3); The housing (1) has an internal cavity. One end of the housing (1) has an air inlet (71), and the other end has a nozzle (91). The internal cavity is located between the air inlet (71) and the nozzle (91). The two ends of the internal cavity are connected to the air inlet (71) and the nozzle (91) respectively. The central axes of the air inlet (71), the nozzle (91), and the internal cavity all extend along the first axis direction (14). The core (3) is housed in the inner cavity, and the shape of the core (3) is adapted to the shape of the inner cavity. The core (3) includes a first core portion (31) and a second core portion (32), and the first core portion (31) and the second core portion (32) are disposed opposite to each other. A first cavity (101) is sealed between the outer wall of the first core (31) and the inner wall of the inner cavity. The first cavity (101) contains a first elastic element (41). The first core (31) is connected to the inner wall of the inner cavity through the first elastic element (41). A second cavity (102) is sealed between the outer wall of the second core (32) and the inner wall of the inner cavity. The second cavity (102) contains a second elastic element (42). The second core (32) is connected to the inner wall of the inner cavity through the second elastic element (42). An air intake channel is formed between the first core (31) and the second core (32). The two ends of the air intake channel are connected to the air inlet (71) and the nozzle (91) respectively. The air intake channel is used to allow raw material gas to pass through. When the raw material gas passes through, the first elastic element (41) and the second elastic element (42) adjust the distance between the first core (31) and the second core (32).

2. The apparatus according to claim 1, characterized in that, The central axes of the first elastic member (41) and the second elastic member (42) both extend along the second axis direction (15), and the second axis direction (15) is orthogonal to the first axis direction (14).

3. The apparatus according to claim 2, characterized in that, Both the first elastic element (41) and the second elastic element (42) are compression springs.

4. The apparatus according to claim 2, characterized in that, It also includes a first sealing ring and a second sealing ring, the central axes of which both extend along the direction of the second axis. The first sealing ring is located between the outer side wall of the first core (31) and the inner side wall of the inner cavity. The outer side wall of the first core (31) presses the first sealing ring against the inner side wall of the inner cavity, so that a first cavity (101) with a sealing arrangement is formed between the outer side wall of the first core (31) and the inner side wall of the inner cavity. The second sealing ring is located between the outer wall of the second core (32) and the inner wall of the inner cavity. The outer wall of the second core (32) presses the second sealing ring against the inner wall of the inner cavity, so that a second cavity (102) with a sealing arrangement is formed between the outer wall of the second core (32) and the inner wall of the inner cavity.

5. The apparatus according to claim 4, characterized in that, Both the first sealing ring and the second sealing ring are made of elastic material.

6. The apparatus according to claim 4, characterized in that, It also includes a first guide member and a second guide member, which are respectively located in the first cavity (101) and the second cavity (102). The first core (31) has a first guide groove on its outer side, which extends along the second axis. The first guide member corresponds to the first guide groove, with one end connected to the side wall of the inner cavity and the other end inserted into the first guide groove to guide the first core (31). The second core (32) has a second guide groove on its outer side. The second guide groove extends along the second axis. The second guide member corresponds to the second guide groove. One end of the second guide member is connected to the side wall of the inner cavity, and the other end is inserted into the second guide groove to guide the second core (32).

7. The apparatus according to any one of claims 1-6, characterized in that, The inner cavity has a circular cross-section in the horizontal direction, and the first core (31) and the second core (32) have semi-circular cross-sections in the horizontal direction. The opposite ends of the first core (31) and the second core (32) are planar. The radii of the first core (31) and the second core (32) are smaller than the radius of the inner cavity.

8. The apparatus according to claim 7, characterized in that, The first core (31) has a first arc-shaped surface that is recessed inward at its planar end, and the first arc-shaped surface extends along the first axis. The second core (32) has a second arc-shaped surface that is recessed inward at its planar end, and the second arc-shaped surface extends along the first axis. The first arc-shaped surface and the second arc-shaped surface are arranged opposite to each other.

9. A polycrystalline silicon reduction furnace system, characterized in that, Includes a reduction furnace, an inlet branch pipe, and the self-adjusting nozzle device as described in any one of claims 1-8. The self-adjusting nozzle device is installed on the chassis of the reduction furnace. The nozzle (91) of the self-adjusting nozzle device is connected to the inner cavity of the reduction furnace, and the air inlet (71) is connected to the air inlet branch pipe. The air inlet branch pipe delivers raw material gas into the furnace cavity of the reduction furnace through the self-adjusting nozzle device.

10. The system according to claim 9, characterized in that, A regulating valve is provided on the intake branch pipe, which is used to regulate the flow rate of the raw material gas in the intake branch pipe.

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