Multi-channel self-adjusting nozzle and polycrystalline silicon reduction system

Abstract

The invention relates to the field of polycrystalline silicon, and discloses a multi-channel self-adjusting nozzle and a polycrystalline silicon reduction system.The nozzle comprises a shell, the shell comprises a base part and a head part arranged on the base part, a first cavity is formed in the base part, a second cavity is formed in the head part, and an adjusting piece is installed in the second cavity through an elastic supporting structure; a first flow channel is arranged in the adjusting part, a second flow channel is arranged between the outer wall of the adjusting part and the inner wall of the head part, air flow flows into the first flow channel and the second flow channel in the first direction after flowing in from the inlet end of the first cavity and then flows out from the outlet end of the second cavity, and the deformation direction of the supporting structure is parallel to the first direction; the pressure of fluid acting on the adjusting part in the flowing process changes along with the flow, the adjusting part is pushed to move in the first direction, the flow area of the first flow channel and the flow area of the second flow channel change along with the adjusting part, the flow speed fluctuation can be effectively reduced, and the flow field uniformity in the reduction furnace, the bottom raw material circulation disturbance capacity and the raw material updating rate can be effectively improved.

Description

Technical Field

[0001] This invention relates to the field of polycrystalline silicon, and more specifically to a multi-channel self-adjusting nozzle and a polycrystalline silicon reduction system. Background Technology

[0002] Polycrystalline silicon is one of the main raw materials for the production of solar cells, and the polycrystalline silicon reduction furnace is an indispensable piece of equipment in solar cell production. Over the past few decades, the solar energy industry has been developing rapidly. Traditional rod-shaped polycrystalline silicon production mainly adopts the modified Siemens process. This method mainly involves subjecting a mixture of trichlorosilane and hydrogen in a certain proportion to a high-temperature vapor-phase chemical deposition reaction. The resulting silicon deposit gradually grows on an electrically heated silicon core, forming rod-shaped polycrystalline silicon products.

[0003] Traditional polysilicon reduction furnaces employ a bottom-inlet and bottom-outlet flow field design. Traditional nozzles have a single nozzle opening with a fixed area, resulting in significant velocity fluctuations when the material quantity changes. During the initial startup and later stages of operation, the low material quantity leads to a low velocity at the nozzle with the fixed area, preventing the cold airflow from reaching the top region. The top of the silicon rod at this time is an area with poor flowability and heat exchange, causing problems such as atomization, cauliflower-like material, and high grounding current. Even using nozzles with smaller opening areas to meet the low material quantity requirements during startup and later stages results in excessively high spray rates at higher material quantities. Excessively high spray rates cause the raw material to flow out of the reduction furnace before fully reacting, leading to low conversion and slow deposition rates. Furthermore, excessively high spray rates carry away a large amount of heat required for the reaction, resulting in heat waste and high power consumption per silicon unit. Meanwhile, when traditional single-nozzle jets enter the reduction furnace, the disturbance to the bottom material circulation is insufficient, resulting in a low bottom material renewal rate and local overheating. Specifically, this manifests as a slow growth rate at the root of the silicon rod, leading to abnormal axial shape (large head and light feet). This can easily cause the silicon rod to tilt and contact the furnace wall, resulting in interphase short circuits (phase loss). In severe cases, it can cause safety hazards such as rod tipping. In addition, the single nozzle does not provide sufficient cooling to the outer wall of the nozzle, and the high temperature of the outer wall can easily corrode and detach metal impurities, affecting the quality of the silicon rod. Summary of the Invention

[0004] The purpose of this invention is to overcome the problems of existing nozzles, such as fixed nozzle area, inability to accommodate changes in material quantity at different times, resulting in material waste and abnormal silicon rod morphology. This invention provides a multi-channel self-adjusting nozzle and polysilicon reduction system. The nozzle provided by this invention has multiple material outlets, and the outlet area adaptively adjusts with changes in material quantity, thereby improving material utilization. Furthermore, because the ejected airflow can disturb both the furnace top and bottom, it improves the uniformity of the flow field within the reduction furnace, enhances the disturbance capability and renewal speed of the material at the bottom, and thus reduces problems such as abnormal silicon rod morphology.

[0005] To achieve the above objectives, a first aspect of the present invention provides a nozzle, wherein the nozzle includes a housing, the housing includes a base and a head disposed on the base, the base is provided with a first cavity for airflow to pass through, the head is provided with a second cavity for airflow to pass through, one end of the first cavity is connected to the outside, the other end of the first cavity is connected to the second cavity, and the other end of the second cavity is connected to the outside. An adjusting component is installed in the second cavity through an elastic support structure. A first flow channel is provided in the adjusting component, and a second flow channel is provided between the outer wall of the adjusting component and the inner wall of the head. One end of the first flow channel and the second flow channel are both connected to the first cavity, and their other ends are both connected to the other end of the second cavity. After the airflow enters from the inlet end of the first cavity, it flows along the first direction and enters the first flow channel and the second flow channel of the second cavity, and then flows out from the other end of the second cavity. The deformation direction of the support structure is parallel to the first direction. The cross-sectional area of ​​the second flow channel along the second direction tends to increase along the direction of airflow, while the cross-sectional area of ​​the first flow channel along the second direction tends to decrease along the direction of airflow. A conical flow regulating part is provided in the first flow channel, and the top of the flow regulating part falls inside the other end of the second cavity. The first direction and the second direction are perpendicular to each other.

[0006] After the gas flow containing raw materials enters from the inlet of the first cavity, it flows in the first direction within the first cavity and then enters the first and second flow channels of the second cavity respectively. The pressure of the gas flow acts on the regulating component, which in turn causes the support structure to undergo elastic deformation. As the gas flow changes, when the force of the gas flow is large, it will drive the regulating component to move in the direction of the gas flow, thereby increasing the flow area of ​​the first and second flow channels. Or when the force of the gas flow is small, the release of the elastic potential energy of the support structure will push the regulating component to move against the direction of the gas flow, thereby decreasing the flow area of ​​the first and second flow channels. This causes the amount of material ejected from the nozzle to change with the gas flow, improving the utilization rate of raw materials. The ejected gas flow ensures the uniformity of the flow field, taking into account the disturbance and renewal speed of the furnace top and bottom, thereby improving the density of silicon rods and reducing problems such as abnormal silicon rod morphology.

[0007] In this application, the raw material gas flow refers to a mixed gas flow containing trichlorosilane and hydrogen.

[0008] Preferably, the support structure includes a support plate fixedly disposed on the head, the adjusting member is located below the support plate and is connected to the support plate through an elastic member, and there is an adjusting gap between the adjusting member and the support plate; The support plate has a first nozzle corresponding to the first flow channel, and the support plate has a second nozzle corresponding to the second flow channel.

[0009] With this structure, as the flow rate of the gas containing raw materials increases, the pressure exerted by the gas on the regulating element also increases, causing the regulating element to move upwards along the first direction. Based on Hooke's Law, it is easy to understand that at this time, the pre-compressed elastic element is continuously compressed until the pressure and elastic force generated by the raw material gas flow reach equilibrium. The upward movement of the regulating element along the first direction increases the flow area of ​​the second and first flow channels, and the flow rate of raw materials flowing through the first and second flow channels and injected into the reduction furnace also increases accordingly. However, the change in the raw material gas distribution ratio is very small. Since the raw material flow rate and the flow area increase simultaneously, the outflow velocity remains basically unchanged, which can continuously maintain the disturbance capability of the bottom raw material circulation and the raw material renewal rate. The silicon rod root grows well, the silicon rod diameter is uniform, and problems such as silicon rod tilting and contacting the furnace wall causing interphase short circuits (phase loss) and rod collapse are not likely to occur. Furthermore, since the flow rate of the raw material gas ejected from the first flow channel fluctuates very little, the injection height into the inner cavity of the reduction furnace remains basically unchanged, which will not disturb the flow field in the reduction furnace. The polycrystalline silicon deposition rate and morphology are controllable, and it is beneficial to reduce power consumption and ensure product density. Meanwhile, the low-temperature raw material flowing through the second flow channel can effectively reduce the temperature of the nozzle outer wall, slow down nozzle corrosion, and thus help reduce silicon rod metal impurities and improve quality.

[0010] Conversely, when the flow rate of the gas containing raw materials decreases, the pressure exerted by the gas on the regulating element also decreases, causing the elastic potential energy generated by the elastic element to be released. This pushes the regulating element downwards along the first direction. Based on Hooke's Law, the elastic element continues to extend to a certain state until the pressure and elastic force reach equilibrium again. The downward movement of the regulating element reduces the flow area of ​​the first and second flow channels, and the flow rate of raw materials flowing through each of these channels also decreases accordingly. However, the change in the distribution ratio of the raw material gas flow is very small. Since both the raw material flow rate and the flow area decrease simultaneously, the change in the outflow velocity remains essentially unchanged. This allows for very small fluctuations in the flow velocity of the raw material gas ejected from the first flow channel, maintaining a stable flow field within the reduction furnace, as well as maintaining the ability to disturb the bottom raw material circulation and the raw material renewal rate.

[0011] Therefore, the multi-channel self-adjusting nozzle provided in this application can effectively reduce flow rate fluctuations and improve the uniformity of the flow field in the reduction furnace, the disturbance capability of the bottom raw material circulation, and the raw material renewal rate.

[0012] Preferably, a guide structure is further provided between the support plate and the adjusting member. The guide structure includes a guide post and a guide groove, both extending along the first direction. One of the guide post is disposed on the support plate, and the other is disposed on the adjusting member. The guide post is inserted into the guide groove. This structure allows the adjusting member to move along the guide direction, preventing rotation.

[0013] Preferably, the nozzle further includes a flow divider, which is disposed within the first cavity. A third flow channel is disposed within the flow divider and communicates with the first flow channel. A core is disposed within the third flow channel, extending into the first flow channel and connected to the flow regulating unit. A fourth flow channel is formed between the outer wall of the flow divider and the inner wall of the first cavity, and this fourth flow channel communicates with the second flow channel. With this structure, the flow divider can pre-divide the raw material airflow entering the first cavity. When the raw material airflow changes, the force exerted on the regulating element after the airflow enters the first and second flow channels changes more significantly, which is beneficial for expanding the flow regulation range of the nozzle.

[0014] Preferably, the cross-sectional area of ​​the second nozzle along the second direction is not less than 1.5 times the maximum cross-sectional area of ​​the second flow channel along the second direction, and can generally be 1.5-2 times.

[0015] Preferably, the cross-sectional area of ​​the fourth flow channel along the second direction is not less than 1.5 times the maximum cross-sectional area of ​​the second flow channel along the second direction, which can generally be 1.5-2 times.

[0016] Preferably, the first nozzle is larger than the outlet of the first flow channel.

[0017] With the above structure, the flow area of ​​the second nozzle and the fourth flow channel is significantly larger than that of the second flow channel, which is beneficial for adjusting the flow area of ​​the second flow channel and thus adjusting the raw material flow rate.

[0018] Preferably, the ratio of the cross-sectional area of ​​the third flow channel along the second direction to the cross-sectional area of ​​the fourth flow channel along the second direction is D, where 6 ≤ D ≤ 8. With this structure, the flow rate of raw materials flowing into the third and fourth flow channels can be effectively controlled by adjusting the flow area ratio D.

[0019] Preferably, the ratio of the minimum cross-sectional area of ​​the first flow channel along the second direction to the cross-sectional area of ​​the fourth flow channel along the second direction is E, where 4 ≤ E ≤ 6. With this structure, the ratio of raw material flow rate exiting the first nozzle and the second nozzle can be further effectively controlled by adjusting the flow area ratio E.

[0020] Preferably, the maximum cross-sectional area of ​​the first flow channel along the second direction is equal to the cross-sectional area of ​​the third flow channel along the second direction. This structure allows the airflow in the third flow channel to smoothly enter the first flow channel, avoiding sudden changes in flow velocity.

[0021] Preferably, a sealing structure is provided between the fluid distributor and the regulating component. This structure isolates the airflow in the third and fourth channels, preventing cross-flow and ensuring proper flow control.

[0022] Preferably, the angle between the conical surface of the flow regulating part and the first direction is F, where 5°≤F≤60°.

[0023] Preferably, the angle between the inner wall of the adjusting member and the first direction is G, where 5°≤G≤60° and G≥F.

[0024] Preferably, the angle between the outer wall of the adjusting member and the first direction is C, where 10°≤C≤45°.

[0025] Preferably, the angle between the axial direction of the second nozzle and the second direction is A, where 0°≤A≤80°.

[0026] With this structure, the flow area in different channels can be adjusted by changing the angles of A, C, G, and F.

[0027] Preferably, the inner wall surface of the head is parallel to the outer wall surface of the head, and the thickness of the head is not less than 2mm. The thickness of the head should be as small as possible while meeting strength requirements. By setting the inner wall surface of the first cavity parallel to the outer wall surface of the head, the thickness of the head can be made uniform throughout. The low-temperature raw material gas flow can effectively cool the head, thereby reducing nozzle corrosion.

[0028] A second aspect of the present invention provides a polysilicon reduction system, wherein the system includes the nozzle described in the first aspect of the present invention, and the system further includes an air intake manifold, the nozzle being connected to the air intake manifold.

[0029] When the material quantity changes during different operating periods in the reduction furnace during polysilicon production, this device, through its first flow channel, second flow channel, and flexible support structure, offers the following advantages compared to existing technologies: 1. It can effectively stabilize the airflow velocity, ensuring the uniformity of the temperature field and flow field throughout the silicon rod growth cycle, thereby improving the silicon rod density and effectively reducing power consumption.

[0030] 2. The ability to maintain stable disturbance to the raw material circulation at the bottom of the reduction furnace and the raw material renewal rate are maintained. The silicon rod roots grow well and the silicon rod diameter is consistent. Problems such as silicon rod tilting and contacting the furnace wall causing interphase short circuits (phase loss) and rod tipping occur.

[0031] 3. The low-temperature raw material flowing through the second flow channel can effectively reduce the temperature of the nozzle outer wall, slow down nozzle corrosion, and avoid the problem of metal falling off after nozzle corrosion, which in turn helps to reduce metal impurities in silicon rods and improve quality. Attached Figure Description

[0032] Figure 1 This is a schematic diagram of the three-dimensional structure of the nozzle; Figure 2 This is a schematic diagram of the internal structure of the nozzle; Figure 3 yes Figure 2 Enlarged view of part a; Figure 4 This is a schematic diagram of the nozzle's planar structure; Figure 5 yes Figure 4 Sectional view A-A'; Figure 6 This is a schematic diagram of the polycrystalline silicon reduction system.

[0033] Explanation of reference numerals in the attached figures 1-Shell; 1a-Base; 1b-Head; 2-First cavity; 3-Adjusting component; 3a-Inner wall of adjusting component; 3b-Outer wall of adjusting component; 4-Flow regulating part; 4a-Conical surface; 5-Second flow channel; 6-Support plate; 6a-First plate; 6b-Second plate; 7-First nozzle; 8-Second nozzle; 9-Flow divider; 10-Core; 11-First flow channel; 12-Third flow channel; 13-Fourth flow channel; 14-Third connecting rib; 15-Second connecting rib; 16-First connecting rib; 17-Elastic component; 18-Adjusting gap; 19-Guide post; 20-Guide groove; 21-Inlet branch pipe. Detailed Implementation

[0034] In the description of this application, it should be understood that the terms "upper", "lower", "vertical", "horizontal", "top", "bottom", 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 of describing this application and simplifying 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 application.

[0035] The terms “first”, “second”, etc. are used to distinguish similar objects, not to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that embodiments of this application can be implemented in orders other than those illustrated or described herein. The objects distinguished by “first”, “second”, etc. are usually of the same class and the number of objects is not limited. For example, the first object can be one or more.

[0036] Furthermore, the term "and / or" in the specification and claims is used to describe the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. The character " / " generally indicates that the preceding and following related objects have an "or" relationship.

[0037] In the description of this application, unless otherwise stated, "a plurality of" means two or more.

[0038] In the description of this application, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and internal connections between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on the specific circumstances.

[0039] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0040] like Figure 1-5 As shown, in some embodiments, a nozzle is provided, the nozzle including a housing 1, the housing 1 including a base 1a and a head 1b disposed on the base 1a, the base 1a having a first cavity 2 for airflow to pass through, the head 1b having a second cavity for airflow to pass through, one end of the first cavity 2 communicating with the outside, the other end of the first cavity 2 communicating with the second cavity, and the other end of the second cavity communicating with the outside; An adjusting member 3 is installed in the second cavity through an elastic support structure. A first flow channel 11 is provided in the adjusting member 3. A second flow channel 5 is provided between the outer wall 3b of the adjusting member and the inner wall of the head 1b. One end of the first flow channel 11 and the second flow channel 5 are connected to the first cavity 2, and their other ends are connected to the other end of the second cavity. After the airflow enters the shell 1 from the inlet end of the first cavity 2, it flows along the first direction and enters the first flow channel 11 and the second flow channel 5 of the second cavity, and then flows out from the other end of the second cavity. The deformation direction of the support structure is parallel to the first direction. The cross-sectional area of ​​the second flow channel 5 along the second direction tends to increase along the direction of airflow, while the cross-sectional area of ​​the first flow channel 11 along the second direction tends to decrease along the direction of airflow. A conical flow regulating part 4 is provided inside the first flow channel 11, and the top of the flow regulating part 4 falls inside the other end of the second cavity. The first direction and the second direction are perpendicular to each other.

[0041] Specifically, the base 1a is cylindrical, the first direction is parallel to the axial direction of the base 1a, the second direction is parallel to the radial direction of the base 1a, and the base 1a and the head 1b are integrally formed.

[0042] In some embodiments, the support structure includes a support plate 6 fixedly disposed on the head 1b, the adjusting member 3 is located below the support plate 6 and is connected to the support plate 6 through a pre-pressed elastic member 17, the adjusting member 3 and the support plate 6 have an adjusting gap 18, a first nozzle 7 is provided on the support plate 6 corresponding to the first flow channel 11, and a second nozzle 8 is provided on the support plate 6 corresponding to the second flow channel 5.

[0043] In some embodiments, the elastic element 17 is a spring, and spring grooves are respectively provided on the support plate 6 and the adjusting element 3. One end of the spring is fixedly connected to the spring groove on the support plate 6, and the other end passes through the adjusting gap 18 and is fixedly connected to the spring groove on the adjusting element 3. To make the movement of the adjusting element 3 smoother, two or more elastic elements 17 are generally provided and evenly distributed around the first nozzle 7.

[0044] To facilitate the replacement of various components, in some embodiments, the support plate 6 includes an annular first plate 6a and an annular second plate 6b. The outer edge of the first plate 6a is threadedly connected to the inner wall of the outlet end of the second cavity. An annular second nozzle 8 is formed on the first plate 6a, dividing the first plate 6a into two annular plates. The two annular plates of the first plate 6a are connected together by a first connecting rib 16. The second plate 6b is located inside the first plate 6a, and its outer edge is threadedly connected to the inner edge of the first plate 6a. The inner circle of the second plate 6b forms the first nozzle 7.

[0045] like Figure 3 As shown, in some embodiments, to prevent the adjusting member 3 from rotating when it moves, a guide structure is also provided between the support plate 6 and the adjusting member 3. The guide structure includes a guide post 19 and a guide groove 20, both of which extend along the first direction. One of them is provided on the support plate 6 and the other is provided on the adjusting member 3. The guide post 19 is inserted into the guide groove 20.

[0046] In this example, the guide post 19 is fixedly installed on the support plate 6, and the guide groove 20 is provided on the adjusting member 3. To make the guidance more stable, two or more guide structures can generally be set, and all the guide structures are evenly distributed around the first nozzle 7.

[0047] In some embodiments, the top of the flow regulating part 4 is located inside the first nozzle 7.

[0048] In some embodiments, the first nozzle 7 is larger than the outlet of the first flow channel 11.

[0049] In some embodiments, the cross-sectional area of ​​the second nozzle 8 along the second direction is not less than 1.5 times the maximum cross-sectional area of ​​the second flow channel 5 along the second direction.

[0050] In some embodiments, the angle between the conical surface 4a of the flow regulating part 4 and the first direction is F, where 5°≤F≤60°, and the cross-sectional area of ​​the first flow channel 11 along the second direction gradually decreases along the flow direction of the airflow.

[0051] In some embodiments, the angle between the inner wall 3a of the adjusting member and the first direction is G, where 5°≤G≤60° and G≥F.

[0052] In some embodiments, the angle between the outer wall 3b of the adjusting member and the first direction is C, where 10°≤C≤45°, and the cross-sectional area of ​​the second flow channel 5 along the second direction gradually increases along the flow direction of the airflow.

[0053] In some embodiments, the angle between the axial direction of the second nozzle 8 and the second direction is A, where 0°≤A≤80°.

[0054] In some embodiments, the inner wall surface of the head 1b is parallel to its outer wall surface, and the thickness of the head 1b is not less than 2 mm.

[0055] In some embodiments, the nozzle further includes a flow divider 9, which is disposed within the first cavity 2. The flow divider 9 has a third flow channel 12 that communicates with the first flow channel 11. A core 10 is disposed within the third flow channel 12, extending into the first flow channel 11 and fixedly connected to the flow regulating part 4. A fourth flow channel 13 is formed between the outer wall of the flow divider 9 and the inner wall of the first cavity 2, and the fourth flow channel 13 communicates with the second flow channel 5.

[0056] Specifically, the flow regulating part 4 and the core 10 are integrally formed. The outer wall of the fluid distributor 9 and the inner wall of the first cavity 2 are connected by a second connecting rib 15, thereby fixing the fluid distributor 9. The core 10 and the inner wall of the third flow channel 12 are connected by a third connecting rib 14, thereby fixing the core 10.

[0057] In some embodiments, a sealing structure is provided between the fluid distributor 9 and the adjusting member 3. Specifically, a sealing groove can be formed on the adjusting member 3, and a sealing ring can be fixed on the fluid distributor 9. The sealing ring is tightened in the sealing groove, thereby achieving a seal between the fluid distributor 9 and the adjusting member 3 and preventing fluid crossflow. More than one sealing structure can be provided between them to enhance the seal. There is a buffer gap between the sealing ring and the corresponding sealing groove of the sealing structure, and the length of the sealing ring along the first direction is greater than the maximum upward displacement of the supporting structure along the first direction. This ensures that when the supporting structure moves up or down along the first direction, the sealing ring can always remain in the sealing groove to achieve an effective sealing effect.

[0058] The fluid separator 9 is cylindrical, the core 10 is cylindrical, and the first cavity 2 is a circular cavity.

[0059] In some embodiments, the ratio of the minimum cross-sectional area of ​​the first flow channel 11 along the second direction to the cross-sectional area of ​​the fourth flow channel 13 along the second direction is E, where 4≤E≤6.

[0060] In some embodiments, the maximum cross-sectional area of ​​the first flow channel 11 along the second direction is equal to the cross-sectional area of ​​the third flow channel 12 along the second direction.

[0061] In some embodiments, the cross-sectional area of ​​the fourth flow channel 13 along the second direction is not less than 1.5 times the maximum cross-sectional area of ​​the second flow channel 5 along the second direction.

[0062] In some embodiments, the ratio of the cross-sectional area of ​​the third flow channel 12 along the second direction to the cross-sectional area of ​​the fourth flow channel 13 along the second direction is D, where 6 ≤ D ≤ 8.

[0063] As can also be seen from the figure, the lower end of the base 1a is provided with external threads, which can be used to connect with the intake branch pipe.

[0064] The working principle of the nozzle provided by this invention is as follows: When the raw material gas flow rate is large, the raw material gas enters the first cavity 2 from the inlet end (lower end) of the first cavity 2. Through the diversion of the flow divider 9, it enters the third flow channel 12 and the fourth flow channel 13 respectively. The raw material gas in the third flow channel 12 then enters the first flow channel 11 connected to it, and the raw material gas in the fourth flow channel 13 enters the second flow channel 5. The pressure of the gas flow acts on the inner and outer walls of the regulating member 3, which compresses the elastic member 17 and pushes the regulating member 3 upward, thereby increasing the flow area of ​​the first flow channel 11 and the second flow channel 5. More raw material gas is injected into the reduction furnace through the corresponding first nozzle 7 and second nozzle 8. When the raw material gas flow rate is low, the elastic potential energy of the elastic element 17 is released, pushing the regulating element 3 downward. This reduces the flow area of ​​the first flow channel 11 and the second flow channel 5. Since the raw material flow rate and the flow area increase simultaneously, the outflow velocity remains essentially constant. This maintains the disturbance capability and material renewal rate of the bottom raw material circulation, resulting in good growth at the silicon rod root and consistent silicon rod diameter. It also reduces the likelihood of problems such as silicon rod tilting and contacting the furnace wall, causing interphase short circuits (phase loss) and rod collapse. Furthermore, because the raw material gas flow rate from the first nozzle fluctuates little, the injection height into the reduction furnace cavity remains essentially constant, preventing disruption of the flow field within the reduction furnace. The polycrystalline silicon deposition rate and morphology are controllable, which helps reduce power consumption and ensure product density. Simultaneously, the low-temperature raw material flowing through the second flow channel effectively reduces the nozzle outer wall temperature, slows down nozzle corrosion, and thus helps reduce metallic impurities in the silicon rod, improving quality.

[0065] In actual production, the relationship between the inlet flow rate and the uniformity of the temperature field and flow field in the furnace before and after the reduction furnace can be realized by adjusting the flow area of ​​the first flow channel 11 and the second flow channel 5 and the initial inner and outer diameter of the distributor 9 in the initial stage of the adjustment, thereby meeting the actual production requirements and improving the quality of silicon rods.

[0066] like Figure 6 As shown, in some embodiments, a polysilicon reduction system is provided, the system including the nozzle, the system further including an air inlet manifold 21, the nozzle being connected to the air inlet manifold 21.

[0067] The preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combinations of various specific technical features in any suitable manner. To avoid unnecessary repetition, the present invention will not describe the various possible combinations separately. However, these simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.

Claims

1. A nozzle, characterized in that, The nozzle includes a housing, which includes a base and a head disposed on the base. The base has a first cavity for airflow to pass through, and the head has a second cavity for airflow to pass through. One end of the first cavity is connected to the outside, and the other end is connected to the second cavity. The other end of the second cavity is also connected to the outside. An adjusting component is installed in the second cavity through an elastic support structure. A first flow channel is provided in the adjusting component, and a second flow channel is provided between the outer wall of the adjusting component and the inner wall of the head. One end of the first flow channel and the second flow channel are both connected to the first cavity, and their other ends are both connected to the other end of the second cavity. After the airflow enters from the inlet end of the first cavity, it flows along the first direction and enters the first flow channel and the second flow channel of the second cavity, and then flows out from the other end of the second cavity. The deformation direction of the support structure is parallel to the first direction. The cross-sectional area of ​​the second flow channel along the second direction tends to increase along the direction of airflow, while the cross-sectional area of ​​the first flow channel along the second direction tends to decrease along the direction of airflow. A conical flow regulating part is provided in the first flow channel, and the top of the flow regulating part falls inside the other end of the second cavity. The first direction and the second direction are perpendicular to each other.

2. The nozzle according to claim 1, characterized in that, The support structure includes a support plate fixedly mounted on the head, the adjusting member is located below the support plate and connected to the support plate via an elastic member, and there is an adjusting gap between the adjusting member and the support plate; The support plate has a first nozzle corresponding to the first flow channel, and the support plate has a second nozzle corresponding to the second flow channel.

3. The nozzle according to claim 2, characterized in that, A guide structure is also provided between the support plate and the adjusting member. The guide structure includes a guide post and a guide groove, both of which extend along the first direction. One of the two is provided on the support plate and the other is provided on the adjusting member. The guide post is inserted into the guide groove.

4. The nozzle according to claim 2 or 3, characterized in that, The nozzle also includes a flow divider, which is disposed in the first cavity. A third flow channel is disposed in the flow divider and communicates with the first flow channel. A core is disposed in the third flow channel and extends into the first flow channel and is connected to the flow regulating part. A fourth flow channel is formed between the outer wall of the flow divider and the inner wall of the first cavity and communicates with the second flow channel.

5. The nozzle according to claim 4, characterized in that, The cross-sectional area of ​​the second nozzle along the second direction is not less than 1.5 times the maximum cross-sectional area of ​​the second flow channel along the second direction; And / or, the cross-sectional area of ​​the fourth flow channel along the second direction is not less than 1.5 times the maximum cross-sectional area of ​​the second flow channel along the second direction; And / or, the first nozzle is larger than the outlet of the first flow channel.

6. The nozzle according to claim 4, characterized in that, The ratio of the cross-sectional area of ​​the third flow channel along the second direction to the cross-sectional area of ​​the fourth flow channel along the second direction is D, where 6 ≤ D ≤ 8. And / or, the ratio of the minimum cross-sectional area of ​​the first flow channel along the second direction to the cross-sectional area of ​​the fourth flow channel along the second direction is E, 4≤E≤6; And / or, the maximum cross-sectional area of ​​the first flow channel along the second direction is equal to the cross-sectional area of ​​the third flow channel along the second direction.

7. The nozzle according to claim 5 or 6, characterized in that, A sealing structure is provided between the fluid distributor and the regulating component.

8. The nozzle according to claim 2 or 3, characterized in that, The angle between the conical surface of the flow regulating part and the first direction is F, where 5°≤F≤60°; And / or, the angle between the inner wall of the adjusting member and the first direction is G, 5°≤G≤60°, and G≥F; And / or, the angle between the outer wall of the adjusting member and the first direction is C, where 10°≤C≤45°; And / or, the angle between the axial direction of the second nozzle and the second direction is A, where 0°≤A≤80°.

9. The nozzle according to any one of claims 1-3, characterized in that, The inner wall of the head is parallel to its outer wall, and the thickness of the head is not less than 2 mm.

10. A polycrystalline silicon reduction system, characterized in that, The system includes a nozzle as described in any one of claims 1-9, and the system further includes an intake manifold, wherein the nozzle is connected to the intake manifold.

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