Air guide device for ingot furnace and ingot furnace

Abstract

The utility model discloses a kind of gas guide device and ingot furnace of ingot furnace, the ingot furnace includes crucible and the cover plate of sealing on the top of crucible, the gas guide device of the ingot furnace includes: gas guide cylinder, extend along up-down direction, at least part of gas guide cylinder is located in the downside of cover plate to stretch into crucible, the part of gas guide cylinder in crucible is formed with the first opening hole of through gas guide cylinder on the circumferential wall of it.According to the gas guide device of the ingot furnace of the utility model, by the gas guide cylinder is stretched into the downside of cover plate crucible, and first opening hole is set on the circumferential wall of gas guide cylinder, argon transverse blowing can be realized, compared with longitudinal vertical blowing mode, transverse airflow can reduce the vortex range of airflow in crucible, improve harmful gas discharge efficiency in crucible, reduce the risk of CO gas generation and dissolving into silicon liquid, reduce silicon liquid carbon concentration, guarantee silicon purity.

Description

Technical Field

[0001] This utility model relates to the field of ingot casting furnace technology, and in particular to a gas guiding device and an ingot casting furnace. Background Technology

[0002] In existing ingot casting furnaces, argon gas easily forms large-scale turbulent vortices at the top of the crucible and on the inner wall of the furnace cavity during the gas guiding process. This causes harmful gases such as SiO volatilized during silicon heating to be trapped and retained by the vortices, preventing them from being quickly discharged through the exhaust system. These trapped SiO gases, in prolonged contact with the graphite cover plate inside the furnace, further react to generate CO gas. This not only increases the amount of CO gas generated but also makes it easier for CO gas to penetrate and dissolve into the high-temperature silicon liquid due to the vortex disturbance. Ultimately, this leads to an increase in the carbon concentration of the silicon liquid, directly affecting the purity of the purified silicon material and making it difficult to meet the production requirements of high-purity silicon. Utility Model Content

[0003] This invention aims to solve at least one of the technical problems existing in the prior art. To this end, this invention provides a gas guiding device for an ingot casting furnace, which enables transverse annular argon purging, improving the efficiency of harmful gas discharge from the furnace, reducing the risk of CO gas generation and dissolution into the molten silicon, lowering the carbon concentration in the molten silicon, and ensuring the purity of the silicon material.

[0004] This utility model also proposes an ingot furnace with a gas guiding device for the ingot furnace.

[0005] According to the first aspect of the present invention, a gas guiding device for an ingot casting furnace includes a crucible and a cover plate sealing the top of the crucible. The gas guiding device includes a gas guiding cylinder that extends in a vertical direction. At least a portion of the gas guiding cylinder is located below the cover plate to extend into the crucible. A first opening penetrating the gas guiding cylinder is formed on the peripheral wall of the portion of the gas guiding cylinder located inside the crucible.

[0006] According to the gas guiding device of the casting furnace of this utility model, by extending the gas guiding cylinder into the crucible under the cover plate and setting a first opening on the peripheral wall of the gas guiding cylinder, argon gas can be purged laterally. Compared with the vertical blowing method, the lateral airflow can reduce the vortex range of the airflow in the crucible, improve the efficiency of harmful gas discharge in the crucible, reduce the risk of CO gas generation and dissolution into the silicon liquid, reduce the carbon concentration of the silicon liquid, and ensure the purity of the silicon material.

[0007] In some embodiments, the number of the first openings is multiple, and the multiple first openings are distributed at intervals in the circumferential direction of the air guide cylinder.

[0008] In some embodiments, the plurality of first openings form a plurality of hole groups on the air guide cylinder, the plurality of hole groups are spaced apart in the vertical direction, and each hole group includes a plurality of first openings spaced apart in the circumferential direction of the air guide cylinder.

[0009] In some embodiments, a plurality of the first openings of two adjacent hole groups in the vertical direction are completely staggered in the circumferential direction of the air guide cylinder.

[0010] In some embodiments, the upper edge of the first opening located on the uppermost side is configured to be flush with the lower surface of the cover plate; and / or, the first opening extends circumferentially along the air guide tube as an elongated hole.

[0011] In some embodiments, a second opening is formed on the lower end face of the air guide tube, which extends through the air guide tube in a vertical direction. The second opening may be one or a plurality of openings spaced apart.

[0012] In some embodiments, the total area of ​​a plurality of first openings on the peripheral wall of the air guide tube is greater than the total area of ​​the second openings on the end face of the air guide tube; and / or, the air guide tube includes a first section and a second section, the first section having the same cross-sectional dimensions in the vertical direction, the first opening being formed on the first section, the second section being connected to the lower end of the first section and extending downward, the cross-sectional dimensions of the second section gradually decreasing in the vertical direction, and the lower end of the second section being open to define the second opening.

[0013] In some embodiments, the length of the gas guide cylinder in the vertical direction is 100mm-200mm, and the gas guiding device further includes a guide pipe adapted to be arranged above the cover plate and extending in the vertical direction. The upper end of the gas guide cylinder is connected to the lower end of the guide pipe, and the lower end of the gas guide cylinder passes through the cover plate and extends into the crucible.

[0014] In some embodiments, the guide tube is detachably connected to the air guide cylinder.

[0015] According to a second aspect of the present invention, a casting furnace includes: a crucible and a cover plate, the cover plate sealing the top of the crucible; according to a first aspect of the present invention, a gas guiding device includes a gas guiding cylinder, at least a portion of which extends through the cover plate into the crucible.

[0016] According to the ingot casting furnace of this utility model, by extending the gas guide tube into the crucible under the cover plate and setting a first opening on the peripheral wall of the gas guide tube, argon gas can be purged laterally. Compared with the vertical blowing method, the lateral airflow can reduce the vortex range of the airflow in the crucible, improve the efficiency of harmful gas discharge in the crucible, reduce the risk of CO gas generation and dissolution into the silicon liquid, reduce the carbon concentration of the silicon liquid, and ensure the purity of the silicon material.

[0017] Additional aspects and advantages of this invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the structure of the gas guide cylinder of the gas guide device of the ingot furnace according to some embodiments of the present utility model; Figure 2 yes Figure 1 The front view of the air delivery tube shown; Figure 3 yes Figure 1 The bottom view of the air guide tube shown; Figure 4 This is a front view of the gas guide cylinder of the gas guide device for a casting furnace according to other embodiments of the present invention; Figure 5 yes Figure 4 The bottom view of the air guide tube shown; Figure 6 This is a cloud map showing the carbon content distribution of the ingot casting furnace under working conditions according to an embodiment of the present invention; Figure 7 This is a cloud map showing the carbon content distribution in existing ingot casting furnaces.

[0019] Figure label: 100, air guide tube; 10, first opening; 20, second opening; 30, first section of cylinder; 40, second section of cylinder. Detailed Implementation

[0020] The embodiments of this utility model are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this utility model, and should not be construed as limiting this utility model.

[0021] The following is for reference. Figures 1-5 Describes a gas guiding device for a casting furnace according to a first aspect embodiment of the present invention.

[0022] like Figures 1-5 As shown, according to the first aspect of the present invention, the ingot casting furnace includes a gas guiding device, a crucible, and a cover plate. The gas guiding device of the ingot casting furnace includes a gas guiding cylinder 100.

[0023] Specifically, the ingot casting furnace includes a crucible and a cover plate sealing the top of the crucible. The gas guiding device includes a gas guiding cylinder 100, which extends in a vertical direction. At least a portion of the gas guiding cylinder 100 is located below the cover plate to extend into the crucible. A first opening 10 is formed on the peripheral wall of the portion of the gas guiding cylinder 100 located inside the crucible.

[0024] like Figures 1-5 As shown, when purifying molten silicon in an ingot casting furnace, the cover plate is made of graphite, which acts as a carbon source in the reaction: silicon reacts with silicon oxide to first generate SiO volatile gas, which then reacts with graphite to generate CO gas. If CO comes into contact with the surface of the molten silicon, it will dissolve into the silicon, leading to an increase in carbon concentration and directly affecting the final purity of the silicon material. To remove harmful volatile gases such as SiO and CO from the furnace, argon gas needs to be introduced into the ingot casting furnace to form a flowing gas flow. The gas guiding device is used to transport the argon gas. The gas guiding device includes a gas guiding cylinder 100, which can be a cylindrical structure extending vertically. The upper end of the gas guiding cylinder 100 is open to receive argon gas, and the lower end of the gas guiding cylinder 100 can be closed or open, and can also have a second opening 20. The gas guiding cylinder 100 can be entirely located under the cover plate to extend into the crucible, or it can be only partially located under the cover plate to extend into the crucible. A first opening 10, perpendicular to the vertical direction, is formed on the peripheral wall of the portion of the gas guide tube 100 located inside the crucible. The inner side of the first opening 10 connects to the inner space of the gas guide tube 100, and the outer side of the first opening 10 connects to the crucible. The gas guide tube 100 achieves communication with the crucible through the first opening 10. The shape of the first opening 10 can be circular, elliptical, square, oblong, etc. For example, as shown... Figure 1 and Figure 2 As shown, the first opening 10 can be elongated.

[0025] In this embodiment, by extending the gas guide tube 100 into the crucible and opening a first opening 10 on the side wall, argon gas can be ejected laterally from the first opening 10. Compared with the structure of a longitudinal argon gas flow path, this significantly reduces the range of eddies in the furnace and reduces the contact between SiO and the graphite cover plate, thereby reducing CO generation. At the same time, after the gas guide tube 100 extends into the crucible, the distance between the argon gas outlet, i.e., the first opening 10, and the surface of the molten silicon is greatly shortened, which can more quickly carry away harmful gases such as SiO and CO volatilized from the surface of the molten silicon, avoiding secondary contact with the molten silicon. In addition, the gas guide tube 100 can be an additional independent component connected to the underside of the cover plate. This configuration of the gas guide tube 100 does not require major modifications to the main structure of the ingot casting furnace, making it highly adaptable and convenient for upgrading existing equipment.

[0026] According to the gas guiding device of the ingot furnace according to the first aspect of the present invention, by extending the gas guiding cylinder 100 into the crucible under the cover plate and providing a first opening 10 on the circumferential wall of the gas guiding cylinder 100, argon gas can be purged laterally. Compared with the vertical blowing method, the lateral airflow can reduce the vortex range in the furnace, improve the efficiency of harmful gas discharge in the furnace, reduce the risk of CO gas generation and dissolution into the silicon liquid, reduce the carbon concentration of the silicon liquid, and ensure the purity of the silicon material. At the same time, it does not require modification of the main structure of the ingot furnace, is adaptable to crucibles of different specifications and production scenarios, facilitates the upgrading of existing equipment, and has both technical practicality and economic value.

[0027] In some embodiments of this utility model, such as Figure 1 , Figure 2 and Figure 4 As shown, there can be multiple first openings 10, which are spaced apart around the circumference of the gas guide tube 100. For example, the number of first openings 10 can be 4, 6, 8, 10, 12, 14, 16, 18, 20, or more. Through the multiple circumferentially spaced first openings 10, argon gas can be uniformly ejected from the circumference of the gas guide tube 100, forming a ring-shaped purge airflow. This prevents harmful gases from accumulating in localized areas due to insufficient airflow, ensuring that impurities in different locations within the furnace are effectively captured and discharged, further improving exhaust uniformity.

[0028] In some embodiments of this utility model, such as Figures 1-5 As shown, multiple first openings 10 on the gas guide cylinder 100 can form multiple hole groups, which are arranged at intervals in the vertical direction. Each hole group includes multiple first openings 10 arranged at intervals in the circumferential direction of the gas guide cylinder 100. The number of hole groups can be multiple, for example, 2, 3, 4, or more. Each hole group can include multiple first openings 10, for example, 2, 3, 4, 5, 6, 8, 10, or more. The multiple hole groups are arranged at intervals in the vertical direction. The vertically spaced arrangement of multiple hole groups enables layered purging of different height areas within the crucible, especially covering the critical reaction area between the underside of the cover plate and the surface of the molten silicon, reducing the residence time of harmful gases, avoiding uneven airflow in the upper and lower areas caused by purging at a single height, and further optimizing exhaust efficiency.

[0029] In some embodiments of this utility model, such as Figure 1 , Figure 2 and Figure 4As shown, multiple first openings 10 in two adjacent hole groups in the vertical direction can be completely staggered in the circumferential direction of the gas guide cylinder 100. This circumferential staggering of the first openings 10 in adjacent hole groups prevents the superposition of airflow at the same circumferential position, thus avoiding the formation of localized strong airflow and preventing the creation of purging blind zones. This allows the argon gas to form a more stable and uniform flow field within the furnace, further reducing the probability of eddy current generation and ensuring that harmful gases are rapidly discharged along a predetermined path. Furthermore, the complete circumferential staggering of the first openings 10 in adjacent hole groups also prevents the first openings 10 from being concentrated in the same circumferential position, reducing structurally weak areas caused by densely packed first openings 10 in the gas guide cylinder 100. This results in a more uniform stress distribution on the gas guide cylinder 100, improving its structural strength and stability during long-term use.

[0030] In some embodiments of this utility model, such as Figure 1 , Figure 2 and Figure 4 As shown, the upper edge of the first opening 10 located on the uppermost side can be configured to be flush with the lower surface of the cover plate. Since each of the first openings 10 is located on the lower side of the cover plate, it allows for direct close-range purging of the lower surface of the cover plate, promptly removing newly generated CO gas near the cover plate and reducing the chance of CO contacting the molten silicon at the source.

[0031] In some embodiments of this utility model, such as Figure 1 , Figure 2 and Figure 4 As shown, the first opening 10 can extend into an elongated shape along the circumference of the gas guide tube 100. The elongated shape of the first opening 10 can reduce the gas jet velocity while ensuring the total area of ​​the opening, avoiding the impact of excessive flow velocity on the gas flow balance in the furnace, while increasing the contact area between argon and harmful gases and improving the argon purging efficiency.

[0032] In some embodiments of this utility model, such as Figure 2 , Figure 3 and Figure 5 As shown, a second opening 20 penetrating the lower end face of the gas guide cylinder 100 can be formed therein, extending vertically through the gas guide cylinder 100. The second opening 20 can be one or multiple openings spaced apart. The upper side of the second opening 20 connects to the interior of the gas guide cylinder 100, and the lower side connects to the crucible. Gas flow between the gas guide cylinder 100 and the crucible is achieved through the first opening 10 and the second opening 20. The number of second openings 20 can be one or more, for example, one, two, three, four, five, or more. Multiple second openings 20 can be arranged at intervals along the circumferential direction of the lower end face of the gas guide cylinder 100, such as... Figure 5 As shown, the number of second openings 20 is one, as follows. Figure 3As shown, there are four second openings 20, arranged in a cross pattern on the lower end face of the gas guide tube 100. The second openings 20 at the lower end of the gas guide tube 100 enable a combined airflow pattern of transverse annular purging at the first opening 10 and longitudinal auxiliary purging at the second opening 20. The transverse airflow from the first opening 10 mainly acts on the lower side of the cover plate and the middle of the crucible, reducing CO generation. The longitudinal airflow from the second opening 20 can directly act on the vicinity of the silicon melt surface, quickly carrying away the SiO gas volatilized from the silicon melt, forming a coordinated exhaust structure from top to bottom, further improving the efficiency of impurity gas removal.

[0033] In some embodiments of this utility model, such as Figures 1-5 As shown, the total area of ​​the plurality of first openings 10 on the peripheral wall of the air guide 100 can be greater than the total area of ​​the second openings 20 on the end face of the air guide 100. That is, the total area of ​​the first openings 10 of the air guide 100 is greater than the total area of ​​the second openings 20, and the gas velocity flowing through the first openings 10 is greater than the gas velocity flowing through the second openings 20. The fact that the total area of ​​the first openings 10 is greater than the total area of ​​the second openings 20 ensures that the main airflow is a transverse annular purging, prioritizing the reduction of eddies, reducing CO generation, and preventing excessively strong longitudinal airflow from triggering eddies again.

[0034] In some embodiments of this utility model, such as Figures 1-5 As shown, the air guide 100 may include a first section 30 and a second section 40. The first section 30 has the same cross-sectional dimensions in the vertical direction, and a first opening 10 is formed on the first section 30. The second section 40 is connected to the lower end of the first section 30 and extends downwards. In the downward direction, the cross-sectional dimensions of the second section 40 gradually decrease, and the lower end of the second section 40 is open to define the second opening 20. That is, as... Figure 4 As shown, the second cylindrical section 40 is conical in shape, with its cross-sectional dimensions gradually decreasing from top to bottom. The first cylindrical section 30 and the second cylindrical section 40 are integrally formed. Designing the second cylindrical section 40 as a gradually decreasing-section cone shape serves two purposes: firstly, it guides the longitudinal airflow to flow more concentratedly towards the silicon melt surface, improving local exhaust efficiency; secondly, the open lower end of the second cylindrical section 40 forms the second opening 20, further ensuring that the total area of ​​the first opening 10 is greater than the total area of ​​the second opening 20, guaranteeing that the main airflow is a transverse annular purging. Additionally, the open design at the lower end of the cone facilitates manufacturing and reduces production difficulty.

[0035] In some embodiments of this utility model, such as Figures 1-5 As shown, the length of the gas guide cylinder 100 in the vertical direction can be 100mm-200mm. The gas guide device may also include: a guide pipe, which is suitable for being arranged above the cover plate and extending in the vertical direction. The upper end of the gas guide cylinder 100 is connected to the lower end of the guide pipe, and the lower end of the gas guide cylinder 100 extends into the crucible through the cover plate.

[0036] In some examples, the length of the gas guide tube 100 in the vertical direction can be 100mm-200mm. For example, the length of the gas guide tube 100 can be 100mm, 110mm, 120mm, 140mm, 160mm, 180mm, 190mm, or 200mm. The length of the gas guide tube 100 is set within the range of 100mm-200mm based on the adaptability design of the ingot furnace cover plate thickness and the crucible height. The length of the gas guide tube 100 ensures that the lower end of the gas guide tube 100 is close enough to the surface of the molten silicon, but does not interfere with other components inside the crucible due to excessive extension.

[0037] In some examples, such as Figures 1-5 As shown, the gas guiding device includes a guide pipe and a gas guiding cylinder 100 from top to bottom. The gas guiding device achieves gas flow with the crucible through the guide pipe and the gas guiding cylinder 100. By dividing the gas guiding device into a guide pipe and a gas guiding cylinder 100, a stable delivery of argon gas can be achieved. At the same time, when the gas guiding cylinder 100 wears out due to long-term high-temperature use or the first opening 10 or the second opening 20 becomes blocked, only the gas guiding cylinder 100 needs to be replaced, without disassembling the entire gas guiding device. This facilitates subsequent maintenance and reduces maintenance costs and downtime.

[0038] In some embodiments of this utility model, such as Figures 1-5 As shown, the guide pipe can be detachably connected to the gas guide cylinder 100. The upper end of the gas guide cylinder 100 is detachably connected to the lower end of the guide pipe, and the connection method can be threaded connection, snap-fit ​​connection, etc. By setting the gas guide cylinder 100 and the guide pipe to be detachably connected, the adaptability of the gas guiding device can be improved. Different lengths or first opening 10 and second opening 20 specifications of the gas guide cylinder 100 can be replaced according to the crucible size and cover plate thickness of different specifications of ingot casting furnaces. Furthermore, the detachable connection between the gas guide cylinder 100 and the guide pipe facilitates the maintenance of the gas guiding device, allowing for disassembly and assembly without the need for professional tools, simplifying the operation process. In addition, if the gas guide cylinder 100 is partially damaged, it is not necessary to replace the entire gas guiding device; only the gas guide cylinder 100 needs to be replaced, reducing equipment operating costs.

[0039] The following is for reference. Figures 1-5 A casting furnace according to a second aspect embodiment of the present invention is described.

[0040] like Figures 1-5 As shown, the ingot casting furnace according to the second aspect of the present invention includes: a crucible, a cover plate, and a gas guiding device for the ingot casting furnace according to the first aspect of the present invention.

[0041] Specifically, a cover plate seals the top of the crucible; at least a portion of the gas delivery tube 100 extends through the cover plate into the crucible.

[0042] like Figures 1-5As shown, a cover plate seals the top of the crucible, and the gas guide tube 100 of the gas guiding device passes through the middle of the cover plate. At least a portion of the gas guide tube 100 extends into the crucible through the cover plate; for example, the entire gas guide tube 100 extends into the crucible through the cover plate, or a portion of the gas guide tube 100 extends into the crucible through the cover plate. Argon gas can be stably delivered to the interior space of the crucible through the gas guiding device. By setting up the gas guiding device, the airflow guiding capability of the gas guiding device can be directly utilized to control harmful gases in the furnace and ensure the purity of silicon material. There is no need to redesign the overall structure of the ingot casting furnace; the function can be upgraded simply by combining existing components, making it highly adaptable and easy to modify. At the same time, the stable argon gas delivery and the sealing effect of the cover plate work together to further optimize the stability of the environment inside the ingot casting furnace, ensuring that the ingot casting furnace can produce silicon crystals efficiently, continuously, and reliably.

[0043] According to the ingot casting furnace of this utility model embodiment, by extending the gas guide cylinder 100 into the crucible under the cover plate and providing a first opening 10 on the periphery of the gas guide cylinder 100, argon gas can be purged horizontally in an annular manner. Compared with the vertical blowing method, the horizontal airflow can reduce the range of vortex in the furnace, improve the efficiency of harmful gas discharge in the furnace, reduce the risk of CO gas generation and dissolution into the silicon liquid, reduce the carbon concentration of the silicon liquid, and ensure the purity of the silicon material.

[0044] The following is for reference. Figures 1-5 This invention describes a specific embodiment of a casting furnace.

[0045] According to a second aspect of the present invention, a casting furnace includes a gas guiding device, a crucible, and a cover plate. The gas guiding device includes a gas guiding cylinder 100 and a flow guide pipe.

[0046] like Figures 1-5 As shown, the guide tube extends vertically and is positioned above the cover plate to transport argon gas.

[0047] like Figures 1-5As shown, the length of the gas guide cylinder 100 in the vertical direction is within the range of 100mm-200mm. The gas guide cylinder 100 includes a first cylinder section 30 and a second cylinder section 40. The second cylinder section 40 is connected to the lower end of the first cylinder section 30, and the first cylinder section 30 and the second cylinder section 40 are integrally formed. The gas guide cylinder 100 extends in the vertical direction, with its upper end connected to the guide tube by a thread, and its lower end extending into the crucible through the cover plate. The upper and lower cross-sectional dimensions of the first cylinder section 30 are the same, and the first cylinder section 30 forms a first opening 10. The second cylinder section 40 forms a second opening 20. The circumferential wall of the gas guide cylinder 100 has a through-hole 10 that allows for transverse annular purging of argon gas. The first opening 10 extends in an elongated shape along the circumference of the gas guide cylinder 100. Multiple first openings 10 on the air guide cylinder 100 can form multiple hole groups, and the multiple hole groups are arranged at intervals in the vertical direction. Each hole group includes multiple first openings 10 arranged at intervals in the circumference of the air guide cylinder 100. The first openings 10 of adjacent hole groups are completely staggered in the circumference. The upper edge of the first opening 10 of the uppermost hole group is flush with the lower surface of the cover plate.

[0048] like Figures 1-5 As shown, a second opening 20 extending vertically through the gas guide cylinder 100 can be formed on the lower end face of the gas guide cylinder 100. The second opening 20 can be one or multiple openings spaced apart. When the second cylinder section 40 is conical with a gradually decreasing cross-sectional area from top to bottom, the number of second openings 20 can be one. When the cross-sectional area of ​​the second cylinder section 40 is the same from top to bottom, multiple second openings 20 can be present, spaced apart along the circumference of the gas guide cylinder 100. The total area of ​​the multiple first openings 10 on the peripheral wall of the gas guide cylinder 100 can be greater than the total area of ​​the second openings 20 on the end face of the gas guide cylinder 100. After argon gas enters the gas guide cylinder 100 through the guide pipe, it flows out from the first opening 10 and the second opening 20 respectively, achieving the purging and discharge of harmful gases in the ingot casting furnace. The shape of the second opening 20 can be circular, elliptical, square, rectangular, polygonal, etc. Figures 1-5 As shown, the shape of the second opening 20 can be circular.

[0049] During assembly, first fix the guide tube in the preset position of the ingot furnace, ensuring that the axis of the guide tube is coaxial with the cover plate. Then, thread the upper end of the gas guide cylinder 100 to the lower end of the guide tube, and extend the lower end into the crucible. Adjust the insertion depth of the gas guide cylinder 100 so that the upper end of the first opening 10 of the uppermost hole group of the first cylinder section 30 is flush with the lower surface of the cover plate, thus completing the assembly.

[0050] During the operation of the ingot casting furnace, argon gas is supplied from an external gas source to the guide pipe, and then flows steadily into the gas guide cylinder 100. Most of the argon gas is ejected laterally from the first opening 10 of the first cylinder section 30, forming an annular purging airflow that covers the lower side of the cover plate and the central area of ​​the crucible, quickly carrying away the CO gas generated near the cover plate due to the reaction of SiO and graphite, while simultaneously preventing SiO gas from flowing towards the cover plate. A small amount of argon gas is ejected longitudinally from the second opening 20 of the second cylinder section 40, directly acting on the vicinity of the silicon melt surface, carrying away the SiO gas volatilized from the silicon melt, and preventing it from contacting the cover plate to generate CO. The airflow at the first opening 10 and the airflow at the second opening 20 work together to expel harmful gases from the ingot casting furnace, achieving efficient exhaust.

[0051] According to the ingot casting furnace of this utility model, by extending the gas guide cylinder 100 into the crucible under the cover plate and providing a first opening 10 on the circumferential wall of the gas guide cylinder 100, argon gas can be purged horizontally in an annular manner. Compared with the vertical blowing method, the horizontal airflow can reduce the vortex range in the furnace, improve the efficiency of harmful gas discharge, reduce the risk of CO gas generation and dissolution into the silicon liquid, reduce the carbon concentration of the silicon liquid, and ensure the purity of the silicon material. At the same time, it does not require modification of the main structure of the ingot casting furnace, is adaptable to different crucible specifications and production scenarios, facilitates the upgrading of existing equipment, and combines technical practicality with economic value. Simulation tests show that... Figure 6 and Figure 7 As shown, Figure 7 That is, the highest carbon concentration at the cover plate in the current scheme is about 20 ppma. Figure 6 In other words, in this embodiment, the highest carbon concentration at the inner cover plate of the ingot furnace is stable below 16 ppma, which is 4 ppma lower than the existing technology, effectively improving the purity of silicon material.

[0052] In the description of this utility model, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.

[0053] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, "a plurality of" means two or more, unless otherwise explicitly specified.

[0054] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a communication connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0055] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. 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.

[0056] Although embodiments of the present invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A gas guiding device for an ingot casting furnace, the ingot casting furnace comprising a crucible and a cover plate sealing the top of the crucible, characterized in that, The air guiding device includes: A gas guide tube (100) extends in the vertical direction, at least a portion of the gas guide tube (100) is located below the cover plate to extend into the crucible, and a first opening (10) is formed on the peripheral wall of the portion of the gas guide tube (100) located inside the crucible.

2. The gas guiding device for the ingot casting furnace according to claim 1, characterized in that, There are multiple first openings (10), and the multiple first openings (10) are distributed at intervals in the circumferential direction of the air guide cylinder (100).

3. The gas guiding device for the ingot casting furnace according to claim 2, characterized in that, The plurality of first openings (10) form a plurality of hole groups on the air guide cylinder (100), and the plurality of hole groups are arranged at intervals in the vertical direction. Each hole group includes a plurality of first openings (10) arranged at intervals in the circumferential direction on the air guide cylinder (100).

4. The gas guiding device for the ingot casting furnace according to claim 3, characterized in that, The first openings (10) of two adjacent hole groups in the vertical direction are completely staggered in the circumferential direction of the air guide cylinder (100).

5. The gas guiding device for the ingot casting furnace according to claim 2, characterized in that, The upper end of the first opening (10) located on the uppermost side is configured to be flush with the lower surface of the cover plate; and / or, the first opening (10) extends in the circumference of the air guide (100) as an elongated hole.

6. The gas guiding device for the ingot casting furnace according to any one of claims 1-5, characterized in that, A second opening (20) is formed on the lower end face of the air guide cylinder (100) and extends through the air guide cylinder (100) in the vertical direction. The second opening (20) may be one or multiple openings spaced apart.

7. The gas guiding device for the ingot casting furnace according to claim 6, characterized in that, The total area of ​​the plurality of first openings (10) on the peripheral wall of the air guide cylinder (100) is greater than the total area of ​​the second openings (20) on the end face of the air guide cylinder (100); and / or, The air guide tube (100) includes a first section (30) and a second section (40). The first section (30) has the same cross-sectional dimensions in the vertical direction. The first opening (10) is formed on the first section (30). The second section (40) is connected to the lower end of the first section (30) and extends downward. In the vertical direction, the cross-sectional dimensions of the second section (40) gradually decrease. The lower end of the second section (40) is open to define the second opening (20).

8. The gas guiding device for the ingot casting furnace according to any one of claims 1-5, characterized in that, The length of the air guide tube (100) in the vertical direction is 100mm-200mm. The gas guiding device further includes a guide pipe, which is adapted to be arranged above the cover plate and extends in the vertical direction. The upper end of the gas guiding cylinder (100) is connected to the lower end of the guide pipe, and the lower end of the gas guiding cylinder (100) extends through the cover plate into the crucible.

9. The gas guiding device for the ingot casting furnace according to claim 8, characterized in that, The guide pipe is detachably connected to the air guide cylinder (100).

10. A casting furnace, characterized in that, include: A crucible and a cover plate, the cover plate sealing the top of the crucible; According to any one of claims 1-9, at least a portion of the gas guiding tube (100) extends through the cover plate into the crucible.

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