High-boiling chlorination furnace and high-boiling material treatment system

Abstract

The application discloses a high-boiling chlorination furnace and a high-boiling substance treatment system, which are used for uniformly mixing chlorine gas and gas-phase high-boiling substances in the high-boiling chlorination furnace and improving the situation that the gas-phase high-boiling substances appear condensation and block the gas inlet pipeline of the chlorine gas. The high-boiling chlorination furnace comprises a furnace body (1), a gas distributor (2), a first porous medium (4), a gas premixing cavity (5) and a high-boiling inlet device (3). The gas distributor (2) is fixed at the bottom of the furnace body (1). The first porous medium (4) is arranged in an inner cavity and located above the gas distributor (2). The gas premixing cavity (5) is located above the first porous medium (4). There is a gap between the gas distribution plate (6) and the first porous medium (4), the part of the inner cavity between the gas distribution plate (6) and the first porous medium (4) forms the gas premixing cavity (5). The high-boiling inlet device (3) is fixed at the bottom of the furnace body (1).

Description

Technical Field

[0001] This invention belongs to the field of polysilicon production, specifically relating to a high-boiling-point chlorination furnace and a high-boiling-point substance treatment system. Background Technology

[0002] During the production of polysilicon, a large number of high-boiling-point byproducts (liquid high-boiling-point polymers with boiling points exceeding 70°C) are generated. These high-boiling-point byproducts have complex structures, and the boiling points of some of them are close, making it difficult to achieve high-value comprehensive utilization through ordinary distillation separation.

[0003] In order to utilize high-boiling-point substances, some companies are currently promoting and using the direct chlorination process for their treatment. This process has significant advantages in terms of initial investment, operating costs, environmental benefits, and economic benefits.

[0004] Currently, the direct chlorination process for treating high-boiling-point substances mainly utilizes a high-boiling-point chlorination furnace. In this furnace, the gaseous high-boiling-point substances react with chlorine and carbon to ultimately produce recyclable products.

[0005] The high-boiling-point chlorination furnace has also revealed some problems during long-term operation: because the temperature of the chlorine gas supplied to the furnace is lower than the boiling point of the high-boiling-point substances, when the chlorine gas and the gaseous high-boiling-point substances are not mixed evenly, the gaseous high-boiling-point substances are easily condensed into liquid high-boiling-point substances after contacting with excess low-temperature chlorine gas, thus clogging the chlorine gas inlet pipe. This ultimately leads to the need to shut down the high-boiling-point chlorination furnace for maintenance, resulting in a short continuous production time. Furthermore, the uneven mixing of chlorine gas and high-boiling-point substances also leads to a smaller contact area with carbon in the reaction zone, resulting in a lower reaction rate and insufficient high-boiling-point substance processing capacity, making it difficult to meet the growing polysilicon production and the high-boiling-point substances that need to be processed. Summary of the Invention

[0006] The technical problem to be solved by the present invention is to address the above-mentioned deficiencies in the prior art by providing a high-boiling-point chlorination furnace and a high-boiling-point substance treatment system, which can make the chlorine gas and the gaseous high-boiling-point substances in the high-boiling-point chlorination furnace mix evenly and improve the situation where the gaseous high-boiling-point substances condense and block the chlorine gas inlet pipe.

[0007] In a first aspect, embodiments of the present invention provide a high-boiling-point chlorination furnace, which includes a furnace body, a gas distributor, a first porous medium, a gas premixing cavity, and a high-boiling-point inlet device. The gas distributor is fixed to the bottom of the furnace body and is used to supply chlorine gas into the inner cavity of the furnace body. The first porous medium is disposed within the inner cavity and located above the gas distributor, used to ensure that the chlorine gas entering the inner cavity is evenly distributed within the first porous medium before being supplied upwards. The gas premixing cavity is located above the first porous medium. The high-boiling-point inlet device is fixed to the bottom of the furnace body, and its outlet end passes through the first porous medium and is located within the gas premixing cavity, used to guide the supplied gaseous high-boiling-point substance and spray it into the gas premixing cavity, so that the gaseous high-boiling-point substance and the chlorine gas are fully mixed within the gas premixing cavity.

[0008] Therefore, the high-boiling-point chlorination furnace provided in this embodiment of the invention, by setting a first porous medium on the gas distributor, allows the chlorine gas transported in the gas distributor to be evenly distributed in the first porous medium and then transported upward to the gas premixing cavity. By setting the outlet end of the high-boiling-point inlet device in the gas premixing cavity, and by guiding the gaseous high-boiling-point substance transported by the high-boiling-point inlet device and spraying it into the gas premixing cavity, the gaseous high-boiling-point substance transported by the high-boiling-point inlet device can be fully mixed with chlorine gas in the gas premixing cavity, improving the mixing uniformity of chlorine gas and gaseous high-boiling-point substance. This can improve the situation where the gaseous high-boiling-point substance is blocked by excess chlorine gas condensation, reducing the number of shutdowns of the high-boiling-point chlorination furnace. Therefore, it can increase the continuous processing time and continuous processing capacity of high-boiling-point substances. When the evenly mixed chlorine gas and gaseous high-boiling-point substance react, it can increase the reaction rate and reaction conversion rate of the gaseous high-boiling-point substance, further increasing the continuous processing capacity of high-boiling-point substances, and helping to save chlorine raw material consumption and reduce costs in the high-boiling-point substance treatment process.

[0009] In some embodiments, the high-boiling-point inlet device includes a high-boiling-point inlet pipe and a classifier wheel. The high-boiling-point inlet pipe is fixed to the bottom of the furnace body, with its axis coinciding with the axis of the furnace body. Its outlet end passes through the first porous medium and is located within the gas premixing cavity. Multiple classifier wheel outlets are provided on the sidewall of the outlet end of the high-boiling-point inlet pipe, and these outlets are evenly distributed around the axis of the high-boiling-point inlet pipe. The classifier wheel is disposed within the area enclosed by the multiple classifier wheel outlets and is fixedly connected to the high-boiling-point inlet pipe. The high-boiling-point gaseous material input through the high-boiling-point inlet pipe is guided by the classifier wheel and then ejected outward from the multiple classifier wheel outlets.

[0010] In some embodiments, the outlet of the grading wheel is oriented perpendicular to the axis of the furnace body.

[0011] In some embodiments, the high-boiling-point chlorination furnace further includes a gas distribution plate (6), which is disposed within the inner cavity and located above the first porous medium (4); a gap exists between the gas distribution plate (6) and the first porous medium (4), and the portion of the inner cavity located between the gas distribution plate (6) and the first porous medium (4) forms the gas premixing cavity (5); the gas distribution plate has multiple through holes, all of which are identical in shape and size. These through holes are arranged in multiple concentric circles, with the center of each concentric circle being the center of the gas distribution plate.

[0012] In some embodiments, the diameter of the gas distribution plate ranges from 50cm to 100cm, and the number of concentric circles is five, wherein the diameter of the smallest concentric circle is between 21cm and 38cm. In the radial direction of the gas distribution plate, the minimum distance between two adjacent through holes is between 4cm and 5cm. The through holes are circular in shape, and their diameters range from 1.8cm to 3cm.

[0013] In some embodiments, the number of the through holes arranged in the concentric circles increases sequentially from the inside out.

[0014] In some embodiments, the high-boiling-point chlorination furnace further includes a second porous medium disposed between the gas distribution plate and the reaction zone, for further mixing of chlorine gas and high-boiling-point gaseous substances transported by the through holes on the gas distribution plate within the second porous medium.

[0015] In some embodiments, the height of the second porous medium is between 50 cm and 100 cm, and the porosity is between 0.4 and 0.8. The material of the second porous medium includes graphite.

[0016] In some embodiments, the inner cavity has a reaction zone (8) located above the gas distribution plate (6); the reaction zone forms a fluidized bed, and the particles added to the fluidized bed are petroleum coke particles; the particle size of the petroleum coke particles is between 100 mesh and 325 mesh, and the density of the petroleum coke particles is 1600 kg / m³. 3 -2100kg / m 3 The height of the gas premixed cavity is between 0.2m and 0.6m.

[0017] In some embodiments, the first porous medium is isotropic. The height of the first porous medium is between 0.5m and 1m, and the porosity of the first porous medium is between 0.4 and 0.8. The material of the first porous medium is resistant to chlorine corrosion.

[0018] In some embodiments, the gas distributor includes a plurality of chlorine inlet devices evenly distributed at the bottom of the furnace body. Each chlorine inlet device includes a chlorine inlet pipe and a bubble cap. The chlorine inlet pipe is fixed to the bottom of the furnace body, and its outlet extends into the inner cavity. The bubble cap is fitted onto the chlorine outlet of the chlorine inlet pipe, and the area between the inner wall of the bubble cap and the outer wall of the chlorine inlet pipe forms the outlet of the chlorine inlet device.

[0019] Secondly, embodiments of the present invention provide a high-boiling-point treatment system for polysilicon production. The high-boiling-point treatment system includes a high-boiling-point chlorination furnace as described in the first aspect above, as well as a chlorine gas delivery pipeline and a gas-phase high-boiling-point product delivery pipeline. The high-boiling-point chlorination furnace is used to react materials introduced into it. The chlorine gas delivery pipeline is connected to a gas distributor of the high-boiling-point chlorination furnace and is used to supply chlorine gas. The gas-phase high-boiling-point product delivery pipeline is connected to a high-boiling-point inlet device of the high-boiling-point chlorination furnace and is used to supply gas-phase high-boiling-point products.

[0020] The high-boiling-point treatment system provided in this embodiment of the invention has the same beneficial effects as the high-boiling-point chlorination furnace described above, and will not be repeated here. Attached Figure Description

[0021] Figure 1 : A structural diagram of a high-boiling-point chlorination furnace provided in an embodiment of the present invention;

[0022] Figure 2 : A structural diagram of a gas distribution plate provided in an embodiment of the present invention;

[0023] Figure 3 : A structural diagram of a high-boiling-point inlet device provided in an embodiment of the present invention;

[0024] Figure 4 : This is a structural diagram of a chlorine inlet device provided in an embodiment of the present invention. Detailed Implementation

[0025] To enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0026] Example 1:

[0027] like Figure 1 As shown, an embodiment of the present invention provides a high-boiling-point chlorination furnace, which includes a furnace body 1, a gas distributor 2, a first porous medium 4, a gas distribution plate 6, and a high-boiling-point inlet device 3.

[0028] For example, the furnace body 1 can be cylindrical in shape, and an inner cavity is formed inside the furnace body 1.

[0029] For example, the furnace body 1 has a heating function, which can enable the material introduced into the high-boiling chlorination furnace to react at a suitable temperature, thereby increasing the reaction rate of the material.

[0030] like Figure 1 As shown, the gas distributor 2 is fixed to the bottom of the furnace body 1 and is used to deliver chlorine gas into the inner cavity of the furnace body 1. The first porous medium 4 is disposed in the inner cavity and located above the gas distributor 2, so that the chlorine gas entering the inner cavity is evenly distributed in the first porous medium 2 and then delivered upward.

[0031] The gas distributor 2 can distribute chlorine gas across the entire cross-section of the inner cavity. Then, the chlorine gas enters the first porous medium 4. Under the action of the first porous medium 2, the distribution of chlorine gas will be fully uniform. Then, under the action of gas pressure, the chlorine gas is uniformly sprayed out from the top of the first porous medium 2.

[0032] For example, the gas distributor 2 is connected to an external chlorine gas delivery pipeline.

[0033] For example, the chlorine gas delivered by the gas distributor 2 is at a low temperature, and the first porous medium 4 is a solid material with good thermal conductivity, which can heat the chlorine gas as it flows upward in the first porous medium 4.

[0034] like Figure 1 As shown, the gas distribution plate 6 is disposed within the inner cavity and is located above the first porous medium 4. A gap exists between the gas distribution plate 6 and the first porous medium 4. The portion of the inner cavity located between the gas distribution plate 6 and the first porous medium 4 forms a gas premixing cavity 5. A high-boiling-point inlet device 3 is fixed to the bottom of the furnace body 1. The outlet end of the high-boiling-point inlet device 3 passes through the first porous medium 4 and is located within the gas premixing cavity 5. It guides the high-boiling-point gaseous material it carries and sprays it into the gas premixing cavity (5) to ensure thorough mixing of the high-boiling-point gaseous material with chlorine gas within the gas premixing cavity (5). The inner cavity includes a reaction zone 8, which is located above the gas distribution plate 6. Figure 2 As shown, the gas distribution plate 6 has through holes 61. The gaseous high-boiling substances output from the outlet of the high-boiling inlet device 3 are mixed with chlorine in the gas premixing cavity 5 and then transported to the reaction zone 8 through the through holes 61 on the gas distribution plate 6 for reaction.

[0035] For example, the high-boiling inlet device 3 is connected to an external gas-phase high-boiling substance delivery pipeline.

[0036] Understandably, the gas distribution plate 6 has a certain shielding effect. Therefore, the chlorine gas sprayed from the top of the first porous medium 2, and the gaseous high-boiling-point substance transported by the high-boiling-point inlet device 3, cannot be directly transported upwards to the reaction zone 8. Instead, they are fully mixed in the premixing cavity 5, improving the mixing uniformity of the chlorine gas and the gaseous high-boiling-point substance. At the same time, the high-temperature chlorine gas heated by the first porous medium is entrained to the outlet of the high-boiling-point inlet device 3, which can improve the situation where the gaseous high-boiling-point substance is blocked by excess chlorine gas condensation. When the uniformly mixed chlorine gas and the gaseous high-boiling-point substance react, the reaction rate and conversion rate of the gaseous high-boiling-point substance can be improved.

[0037] Therefore, the high-boiling-point chlorination furnace provided in this embodiment of the invention, by setting a first porous medium 4 on the gas distributor 2, can make the chlorine gas transported in the gas distributor 2 evenly distributed in the first porous medium 4 and then transported upward to the gas premixing cavity 5; by setting the outlet end of the high-boiling-point inlet device 3 in the gas premixing cavity 5, and by guiding the gaseous high-boiling-point substance transported by the high-boiling-point inlet device 3 and spraying it into the gas premixing cavity (5), the gaseous high-boiling-point substance transported by the high-boiling-point inlet device 3 and the chlorine gas can be fully mixed in the gas premixing cavity 5, which improves the mixing uniformity of chlorine gas and gaseous high-boiling-point substance. At the same time, the high-temperature chlorine gas heated by the first porous medium will be drawn to the outlet of the high-boiling-point inlet device 3, which can improve the situation where the gaseous high-boiling-point substance is blocked by the condensation of excess chlorine gas and the chlorine gas inlet pipe, reduce the number of times the high-boiling-point chlorination furnace is shut down, and thus can increase the continuous processing time of high-boiling-point substances and increase the continuous processing capacity of high-boiling-point substances. When chlorine and high-boiling-point gaseous substances are mixed evenly, the reaction rate and conversion rate of the high-boiling-point gaseous substances can be increased, thereby increasing the continuous processing capacity of the high-boiling-point substances and saving on the consumption of chlorine raw materials, thus reducing the cost of high-boiling-point substance treatment.

[0038] In some embodiments, such as Figure 3 As shown, the high-boiling-point inlet device 3 includes a high-boiling-point inlet pipe 31 and a classifier wheel 32. The high-boiling-point inlet pipe 31 is fixed to the bottom of the furnace body 1, with its axis coinciding with the axis of the furnace body 1. Its outlet end passes through the first porous medium 4 and is located in the gas premixing cavity 5. Multiple classifier wheel outlets 33 are provided on the side wall of the outlet end of the high-boiling-point inlet pipe 31, and the classifier wheel outlets 33 are evenly distributed around the axis of the high-boiling-point inlet pipe 31. The classifier wheel 32 is located in the area enclosed by the multiple classifier wheel outlets 33 and is fixedly connected to the high-boiling-point inlet pipe 31. The gaseous high-boiling-point substances input from the high-boiling-point inlet pipe 31 are guided by the classifier wheel 32 and then sprayed outward from the multiple classifier wheel outlets 33.

[0039] In some examples, the orientation of the grading wheel outlet 33 is perpendicular to the axis of the furnace body 1.

[0040] Understandably, the high-boiling inlet pipe 31 is vertically positioned at the center of the furnace body 1, and the stage wheel outlet 33 is oriented horizontally.

[0041] The classifier wheel 32 has multiple blades circumferentially, which guide the airflow when it is directed towards it. Since the classifier wheel outlet 33 is uniformly distributed around the axis of the high-boiling-point inlet pipe 31, the high-boiling-point gaseous material input from the high-boiling-point inlet pipe 31, after being guided by the classifier wheel 32, can be uniformly sprayed around the high-boiling-point inlet pipe 31, improving the mixing uniformity between the high-boiling-point gaseous material and the chlorine entering the gas premixing cavity 5. Furthermore, due to the pressure, the sprayed high-boiling-point gaseous material airflow will entrain chlorine to the center of the gas premixing cavity 5, causing the high-boiling-point gaseous material and chlorine to mix violently at the classifier wheel outlet, further improving the mixing uniformity between the high-boiling-point gaseous material and the chlorine entering the gas premixing cavity 5, while also increasing the temperature of the mixed gas, preventing the high-boiling-point gaseous material from condensing. Simultaneously, the cavity area of ​​the gas premixing cavity 5 reduces the resistance when the high-boiling-point gaseous material is sprayed from the classifier wheel outlet 33, reducing the load and energy consumption of the high-boiling-point gaseous material transport pipeline.

[0042] Through repeated simulations and calculations by the inventors, the above-mentioned setup can effectively and thoroughly mix high-boiling-point gaseous substances with chlorine, thereby increasing the reaction conversion rate of high-boiling-point gaseous substances after entering reaction zone 8. This helps to save on the consumption of chlorine raw materials, thus reducing the cost of high-boiling-point gaseous substance treatment.

[0043] In some embodiments, such as Figure 2 As shown, the gas distribution plate 6 has multiple through holes 61, all of which are identical in shape and size. These through holes 61 are arranged in multiple concentric circles, with the center of each circle being the center of the gas distribution plate 6.

[0044] Understandably, the above arrangement reduces the difficulty of setting up the through-holes 61 and allows the mixed chlorine gas and high-boiling gas mixture to be simultaneously delivered to the reaction zone 8 through multiple through-holes 61, increasing the amount of chlorine gas and high-boiling gas entering the reaction zone 8 and improving the reaction rate of the high-boiling gas. Furthermore, because the stage wheel outlet 33 is uniformly distributed around the axis of the high-boiling inlet pipe 31, the high-boiling gas ejected from the stage wheel outlet 33 will move uniformly towards the side wall of the furnace body 1 with the high-boiling inlet pipe 31 as the center. On the same horizontal plane, the mixing degree of chlorine gas and high-boiling gas at positions equidistant from the high-boiling inlet pipe 31 is the same, and the closer to the side wall of the furnace body 1, the more uniform the mixing of chlorine gas and high-boiling gas. Arranging the multiple through-holes 61 into multiple concentric circles ensures that the mixing degree of the chlorine gas and high-boiling gas mixture entering the reaction zone 8 through the same concentric circle is the same, improving the stability of the chlorine gas and high-boiling gas mixture entering the reaction zone 8.

[0045] In some embodiments, such as Figure 2 As shown, the diameter of the gas distribution plate 6 ranges from 50cm to 100cm, and there are five concentric circles, with the smallest concentric circle having a diameter between 21cm and 38cm. In the radial direction of the gas distribution plate 6, the minimum distance between two adjacent through holes 61 is between 4cm and 5cm. The through holes 61 are circular in shape, and their diameters range from 1.8cm to 3cm.

[0046] For example, the diameter of the smallest concentric circle can be 21cm, 30cm or 38cm, etc., the minimum distance between two adjacent through holes 61 is 4cm, 4.5cm or 5cm, etc., and the diameter of the through hole 61 is 1.8cm, 2.3cm or 3cm, etc.

[0047] With the above settings, the gas distribution plate 6 can provide appropriate obstruction to the gas mixture of chlorine and high-boiling gaseous substances. In other words, under these conditions, it can prevent the high-boiling substances and chlorine from entering the reaction zone 8 through the through hole 61 before they are evenly mixed in the gas premixing cavity 5. At the same time, it can prevent the large resistance to the evenly mixed chlorine and high-boiling gaseous substances entering the reaction zone 8 due to the small size and number of through holes 61, thus maintaining a normal supply of chlorine and high-boiling gaseous substances into the reaction zone 8.

[0048] In some embodiments, such as Figure 2 As shown, the number of through holes 61 arranged in concentric circles increases sequentially from the inside out.

[0049] For example, the five concentric circles mentioned above are, in order, a first concentric circle, a second concentric circle, a third concentric circle, a fourth concentric circle, and a fifth concentric circle. The number of through holes 61 arranged in the first concentric circle is between 6 and 24; the number of through holes 61 arranged in the second concentric circle is between 12 and 30; the number of through holes 61 arranged in the third concentric circle is between 18 and 36; the number of through holes 61 arranged in the fourth concentric circle is 42; and the number of through holes 61 arranged in the fifth concentric circle is 48. The through holes 61 arranged in the first, fourth, and fifth concentric circles are evenly distributed; the through holes 61 arranged in the second concentric circle are evenly distributed in groups of two; and the through holes 61 arranged in the third concentric circle are evenly distributed in groups of three.

[0050] For example, such as Figure 2 As shown, there are 6 through holes 61 arranged in the first concentric circle, 12 through holes 61 arranged in the second concentric circle, and 18 through holes 61 arranged in the third concentric circle.

[0051] As mentioned above, combined Figure 1 and Figure 2 The closer to the side wall of the furnace body 1, the more uniform the mixing of the high-boiling gaseous substance and chlorine. By minimizing the number of through holes 61 arranged in the first concentric circle, the amount of unevenly mixed high-boiling gaseous substance and chlorine transported to the reaction zone 8 through the through holes 61 arranged in the first concentric circle can be reduced. By maximizing the number of through holes 61 arranged in the fifth concentric circle, the fully mixed high-boiling gaseous substance and chlorine can be transported to the reaction zone 8 through the through holes 61 as quickly as possible.

[0052] Furthermore, simulation experiments show that the above-mentioned through-hole 61 setting method can ensure the optimal residence time of gaseous high-boiling substances in the gas premixing cavity 5, which is more conducive to the vigorous mixing of chlorine and high-boiling substances in the premixing cavity, and optimizes the flow distribution of the mixed gas of gaseous high-boiling substances and chlorine when it enters the reaction zone 8.

[0053] In some embodiments, the high-boiling-point chlorination furnace further includes a second porous medium 7 disposed between the gas distribution plate 6 and the reaction zone 8, for further mixing of chlorine gas and gaseous high-boiling-point substances transported by the through holes 61 on the gas distribution plate 6 within the second porous medium 7.

[0054] Through the above settings, the mixing degree of chlorine and high-boiling gaseous substances can be further improved. Furthermore, the second porous medium 7 can also make the mixture of chlorine and high-boiling gaseous substances evenly distributed across the entire cross-section of the furnace body 1, increasing the distribution area of ​​the mixture of chlorine and high-boiling gaseous substances in the reaction zone 8, providing the reaction zone with a uniformly flowing mixture of chlorine and high-boiling gaseous substances, thereby increasing the reaction rate of materials in the high-boiling chlorination furnace.

[0055] In some embodiments, the height of the second porous medium 7 is between 50 cm and 100 cm, and the porosity is between 0.4 and 0.8.

[0056] For example, the height of the second porous medium 7 is 50cm, 70cm or 100cm, etc., and the porosity of the second porous medium 7 is 0.4, 0.6 or 0.8, etc.

[0057] Through experiments and numerical simulations, it was found that this ensures that the mixed gas injected through the through hole 61 can be evenly distributed on the radial cross section inside the furnace, and the required height of the second porous medium 7 is small, which helps to save materials and reduce the overall size of the high-boiling chlorination furnace.

[0058] In some embodiments, the material of the second porous medium 7 includes graphite.

[0059] Graphite materials can more easily form porous morphologies in the second porous medium 7, and the graphite on the upper layer of the second porous medium 7 can also participate in the reaction of high-boiling substances, which is beneficial to further improve the reaction rate in the high-boiling chlorination furnace.

[0060] It should be noted that the second porous medium 7 can be a single-layer structure, that is, a structure with a uniform porosity and arrangement; or it can be a multi-layer structure, that is, a structure in which the porosity and arrangement of each layer of porous medium are different. In this embodiment, the second porous medium 7 adopts a uniform porosity and arrangement.

[0061] In some embodiments, the reaction zone 8 is formed with a fluidized bed, and the particles added to the fluidized bed are petroleum coke particles; the particle size of the petroleum coke particles is between 100 mesh and 325 mesh, and the density of the petroleum coke particles is 1600 kg / m³. 3 -2100kg / m 3 between.

[0062] For example, the particle size of petroleum coke particles is 100 mesh, 200 mesh, or 325 mesh, and the density of petroleum coke particles is 1600 kg / m³. 3 1800kg / m 3 Or 2100kg / m 3 wait.

[0063] By setting up a fluidized bed, the solid and fluid are in intense relative motion, which accelerates the heat and mass transfer between substances, thereby enhancing the contact processes between gas and solid, liquid and solid, or gas and liquid and solid. The large surface area of ​​petroleum coke particles increases the contact area between them and oxygen-containing high-boiling-point substances and chlorine, thus significantly improving the reaction rate between these substances and the overall throughput of high-boiling-point substances.

[0064] In some embodiments, the height of the gas premixing cavity 5 is between 0.2m and 0.6m.

[0065] For example, the height of the premixed cavity 5 can be 0.2m, 0.4m or 0.6m, etc.

[0066] The above configuration allows the gas premixing cavity 5 to maintain a suitable volume, providing the space required for thorough mixing of chlorine and high-boiling-point substances. Furthermore, for high-boiling-point substances with high solid content, the gas premixing cavity 5 provides a larger cavity at the stager outlet 33, effectively reducing the risk of blockage, saving on maintenance frequency and costs, and increasing the overall throughput of high-boiling-point substances.

[0067] In some embodiments, the first porous medium 4 is isotropic. The height of the first porous medium 4 is between 0.5m and 1m, and the porosity of the first porous medium 4 is between 0.4 and 0.8.

[0068] For example, the height of the first porous medium 4 can be 0.5m, 0.7m or 1m, etc., and the porosity of the first porous medium 4 can be 0.4, 0.6 or 0.8, etc.

[0069] In the prior art, in order to prevent the first porous medium 4 from becoming clogged, the height of the first porous medium 4 needs to be set to be low and the porosity of the first porous medium 4 needs to be set to be large. However, this setting is not conducive to the distribution and heating of chlorine gas in the first porous medium 4.

[0070] The above-described arrangement of the first porous medium 4 in this embodiment of the invention fully considers the mixing characteristics of chlorine and high-boiling substances in the gas premixing cavity 5 and the clogging characteristics of the first porous medium 4. It can ensure the distribution and heating effect of chlorine when passing through the first porous medium 4, as well as the full mixing of chlorine and high-boiling substances in the future. It also reduces the required height of the first porous medium 4, thereby reducing the space occupied by the first porous medium 4 in the furnace body 1.

[0071] In some embodiments, the material of the first porous medium 4 is a material resistant to chlorine corrosion.

[0072] For example, the material of the first porous medium 4 is graphite. Under suitable conditions, the aforementioned high-boiling gaseous substances can also react with the graphite in the first porous medium 4.

[0073] This can slow down the corrosion of the first porous medium 4 by chlorine gas, which is beneficial to maintaining the structural stability of the first porous medium 4 and reducing the number of maintenance times for the first porous medium 4.

[0074] In some embodiments, combined with Figure 1 and Figure 4 The gas distributor 2 includes multiple chlorine inlet devices evenly distributed at the bottom of the furnace body 1. Each chlorine inlet device includes a chlorine inlet pipe 21 and a bubble cap 23. The chlorine inlet pipe 21 is fixed to the bottom of the furnace body 1, and its outlet extends into the inner cavity. The bubble cap 23 is attached to the chlorine outlet 22 of the chlorine inlet pipe 21, and the area between the inner wall of the bubble cap 23 and the outer wall of the chlorine inlet pipe 21 forms the outlet of the chlorine inlet device.

[0075] With the above settings, when the chlorine gas transported by the chlorine inlet pipe 21 encounters the bubble 23, the chlorine gas flows downward and diffuses around the chlorine inlet pipe 21. This helps to reduce the flow rate of the chlorine gas and increase the diffusion range of the chlorine gas, allowing the chlorine gas to enter the first porous medium 4 from a wider range, and thus making the chlorine gas more evenly distributed after flowing out of the first porous medium 4.

[0076] In some examples, the furnace body 1 can be made of stainless steel or carbon steel with a graphite sleeve attached to the inner wall, the gas distributor 2, the first porous medium 4, and the gas distribution plate 6 can be made of corrosion-resistant materials such as stainless steel, and the high-boiling inlet device 3 can be made of corrosion-resistant materials such as silicon nitride.

[0077] The working process of the high-boiling-point chlorination furnace in this embodiment of the invention is described below:

[0078] The chlorine gas transported in the chlorine gas pipeline has a temperature range of 0℃-40℃, a pressure range of 0.1MPa-0.3MPa, and a flow rate range of 0-0.3t / h. The chlorine gas enters the interior of the furnace body 1 through the gas distributor 2, then enters the first porous medium 4, and after uniform diffusion inside the first porous medium 4, it is ejected from the top of the first porous medium 4 into the gas premixing cavity 5.

[0079] The temperature range of the high-boiling-point gaseous substance transported in the gas-phase high-boiling-point gaseous substance conveying pipeline is 160℃-200℃, the pressure range is 0.1MPa-0.3MPa, and the flow rate range is 0.6t / h-2t / h. The high-boiling-point gaseous substance enters the interior of the furnace body 1 through the high-boiling-point inlet device 3, and after being guided by the classifier wheel 32, it is sprayed outward from the outlets 33 of multiple classifier wheels into the gas premixing cavity 5 and entrains chlorine gas in the gas premixing cavity 5, so that the chlorine gas and the high-boiling-point gaseous substance are initially mixed.

[0080] Inside the gas premixing cavity 5, after the chlorine gas and the high-boiling gaseous substance undergo preliminary mixing, it moves upward to the gas distribution plate 6. Under the action of the gas distribution plate 6, the mixed gas of chlorine gas and the high-boiling gaseous substance moves to the top porous medium 7 through multiple through holes 61. Through the reasonable setting of the shape, number and distribution of the multiple through holes 61 on the gas distribution plate 6, the mixed gas of chlorine gas and the high-boiling gaseous substance can be fully mixed a second time when passing through the gas distribution plate 6.

[0081] The chlorine gas and the high-boiling gas mixture, after being thoroughly mixed for the second time, enter the second porous medium 7 and undergo a third thorough mixing and uniform distribution within the second porous medium 7. The mixture then flows upward into the reaction zone 8 at a basically uniform flow rate.

[0082] The fluidized bed and petroleum coke particles within reaction zone 8 not only ensure thorough mixing of chlorine gas and gaseous high-boiling-point substances required for the high-boiling-point chlorination furnace reaction, but also utilize the petroleum coke particles to react with oxygen-containing high-boiling-point substances, generating a large amount of heat. This promotes the reaction rate and conversion rate within the high-boiling-point chlorination furnace, significantly increasing its maximum daily throughput of high-boiling-point substances. The temperature range within reaction zone 8 is 800℃-1000℃. The high-boiling-point substances are mainly composed of Si. x Cl yIt is composed of Cl6OSi2, Cl5HOSi2 and Cl4H2OSi2.

[0083] In actual production, the continuous operation time of the high-boiling-point chlorination furnace provided in this embodiment of the invention can be extended to 2-3 months. The reason is that the high-boiling-point chlorination furnace provided in this embodiment of the invention fully considers the mixing characteristics of chlorine and high-boiling-point substances, the clogging characteristics of the bottom pipe, and the role of petroleum coke particles in the fluidized bed in the reaction zone 8. It determines the appropriate porosity of the first porous medium 4 and the second porous medium 7, which can greatly reduce the filling height of the first porous medium 4 and the second porous medium 7, and significantly improve the continuous operation time of the high-boiling-point chlorination furnace.

[0084] Example 2:

[0085] This invention also provides a high-boiling-point treatment system for polysilicon production, characterized by comprising a high-boiling-point chlorination furnace as described in Embodiment 1 above, as well as a chlorine gas delivery pipeline and a gaseous high-boiling-point substance delivery pipeline. The high-boiling-point chlorination furnace is used to react materials introduced into it. The chlorine gas delivery pipeline is connected to a gas distributor 2 of the high-boiling-point chlorination furnace to supply chlorine gas. The gaseous high-boiling-point substance delivery pipeline is connected to a high-boiling-point inlet device 3 of the high-boiling-point chlorination furnace to supply gaseous high-boiling-point substances.

[0086] Therefore, chlorine and high-boiling-point gaseous substances can be mixed evenly in a high-boiling-point chlorination furnace and react there, which increases the reaction rate and conversion rate of the high-boiling-point gaseous substances. This improves the processing rate of high-boiling-point substances in the high-boiling-point substance treatment system, helps to save on the consumption of chlorine raw materials, and reduces the cost of high-boiling-point substance treatment.

[0087] 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 high-boiling-point chlorination furnace, comprising a furnace body (1), characterized in that, Also includes: A gas distributor (2) is fixed to the bottom of the furnace body (1) and is used to deliver chlorine gas into the inner cavity of the furnace body (1); The first porous medium (4) is disposed in the inner cavity and located above the gas distributor (2) to make the chlorine gas entering the inner cavity evenly distributed in the first porous medium (4) and then transported upward. A gas premixed cavity (5) is located above the first porous medium (4); and, A high-boiling-point inlet device (3) is fixed at the bottom of the furnace body (1). The outlet end of the high-boiling-point inlet device (3) passes through the first porous medium (4) and is located in the gas premixing cavity (5). It is used to guide the gaseous high-boiling-point substance it conveys and spray it into the gas premixing cavity (5) so that the gaseous high-boiling-point substance and the chlorine are fully mixed in the gas premixing cavity (5). The high-boiling inlet device (3) includes: A high-boiling-point inlet pipe (31) is fixed to the bottom of the furnace body (1), with its axis coinciding with the axis of the furnace body (1). Its outlet end passes through the first porous medium (4) and is located within the gas premixing cavity (5). Multiple stage wheel outlets (33) are provided on the side wall of the outlet end of the high-boiling-point inlet pipe (31), and these stage wheel outlets (33) are evenly distributed around the axis of the high-boiling-point inlet pipe (31). A classifier wheel (32) is set in the area enclosed by multiple classifier wheel outlets (33) and is fixedly connected to the high-boiling inlet pipe (31); the gaseous high-boiling substance input by the high-boiling inlet pipe (31) is guided by the classifier wheel (32) and then sprayed outward from the multiple classifier wheel outlets (33); The orientation of the grader outlet (33) is perpendicular to the axis of the furnace body (1); The high-boiling-point chlorination furnace also includes a gas distribution plate (6), which is disposed in the inner cavity and located above the first porous medium (4); there is a gap between the gas distribution plate (6) and the first porous medium (4), and the portion of the inner cavity located between the gas distribution plate (6) and the first porous medium (4) forms the gas premixing cavity (5). The gas distribution plate (6) has a plurality of through holes (61), and the plurality of through holes (61) are identical in shape and size; The multiple through holes (61) are arranged in multiple concentric circles, and the center of each of the multiple concentric circles is the center of the gas distribution plate (6); The number of the through holes (61) arranged in concentric circles increases sequentially from the inside out.

2. The high-boiling-point chlorination furnace according to claim 1, characterized in that, The diameter range of the gas distribution plate (6) is 50cm-100cm, and the number of concentric circles is five, of which the smallest concentric circle has a diameter between 21cm and 38cm. In the radial direction of the gas distribution plate (6), the minimum distance between two adjacent through holes (61) is between 4cm and 5cm; The through hole (61) is circular in shape, and the diameter of the through hole (61) is between 1.8cm and 3cm.

3. The high-boiling-point chlorination furnace according to claim 1, characterized in that, The inner cavity has a reaction zone (8), which is located above the gas distribution plate (6); The high-boiling chlorination furnace also includes a second porous medium (7), which is disposed between the gas distribution plate (6) and the reaction zone (8) to further mix the chlorine gas and gaseous high-boiling substances transported by the through holes (61) on the gas distribution plate (6) inside the second porous medium (7).

4. The high-boiling-point chlorination furnace according to claim 3, characterized in that, The height of the second porous medium (7) is between 50cm and 100cm, and the porosity is between 0.4 and 0.

8. The material of the second porous medium (7) includes graphite.

5. The high-boiling-point chlorination furnace according to claim 1, characterized in that, The inner cavity has a reaction zone (8), which is located above the gas distribution plate (6); The reaction zone (8) is formed with a fluidized bed, and the particles added to the fluidized bed are petroleum coke particles; the particle size of the petroleum coke particles is between 100 mesh and 325 mesh, and the density of the petroleum coke particles is 1600 kg / m³. 3 -2100kg / m 3 between; The height of the gas premixed cavity (5) is between 0.2m and 0.6m.

6. The high-boiling-point chlorination furnace according to claim 1, characterized in that, The first porous medium (4) is isotropic; The height of the first porous medium (4) is between 0.5m and 1m, and the porosity of the first porous medium (4) is between 0.4 and 0.

8. The material of the first porous medium (4) is a material resistant to chlorine corrosion.

7. The high-boiling-point chlorination furnace according to claim 1, characterized in that, The gas distributor (2) includes a plurality of chlorine inlet devices evenly distributed at the bottom of the furnace body (1), the chlorine inlet devices comprising: A chlorine inlet pipe (21) is fixed to the bottom of the furnace body (1), and its outlet extends into the inner cavity; and, A blister (23) is attached to the chlorine outlet (22) of the chlorine inlet pipe (21). The area between the inner wall of the blister (23) and the outer wall of the chlorine inlet pipe (21) forms the outlet of the chlorine inlet device.

8. A high-boiling-point treatment system for polycrystalline silicon production, characterized in that, Includes a high-boiling-point chlorination furnace as described in any one of claims 1-7, and a chlorine gas delivery pipeline and a gaseous high-boiling-point substance delivery pipeline; The high-boiling-point chlorination furnace is used to react the materials introduced into it. The chlorine gas delivery pipeline is connected to the gas distributor (2) of the high-boiling chlorination furnace to provide chlorine gas; The gas phase high boiling point transport pipeline is connected to the high boiling point inlet device (3) of the high boiling point chlorination furnace and is used to provide gas phase high boiling point.

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