Polycrystalline silicon high-boiling residue hydrolysis device and polycrystalline silicon high-boiling residue treatment system
By setting up a buffer layer and an exhaust system inside the hydrolysis reactor, the problem of sudden pressure increase inside the hydrolysis reactor for high-boiling polysilicon is mitigated, explosion is avoided, and safe and controllable treatment of high-boiling polysilicon is achieved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- XINTE ENERGY CO LTD
- Filing Date
- 2025-05-14
- Publication Date
- 2026-05-05
AI Technical Summary
Traditional high-boiling-point hydrolysis reactors pose an explosion risk in polysilicon production due to sudden pressure increases, and existing control methods rely on manual operation with uncertain effectiveness.
A buffer layer is set inside the hydrolysis reactor. The buffer layer floats on the surface of the reaction solution and slowly releases high-boiling polycrystalline silicon through the flow channel to reduce the reaction rate, reduce heat and gas generation, and exhaust pipe and water seal tank are set to discharge waste gas.
It effectively reduces the risk of sudden pressure increases inside the hydrolysis reactor, avoids explosions, and improves equipment safety and operational controllability.
Smart Images
Figure CN224194701U_ABST
Abstract
Description
Technical Field
[0001] This utility model belongs to the field of chemical equipment technology, specifically relating to a polycrystalline silicon high-boiling-point hydrolysis device and a polycrystalline silicon high-boiling-point treatment system. Background Technology
[0002] With increasing global emphasis on clean energy and sustainable development, the polysilicon industry has ushered in unprecedented development opportunities. However, this booming industry also faces the challenge of handling high-boiling-point substances. In the polysilicon production process, high-boiling-point devices play a crucial role, responsible for cracking high-boiling-point substances (including trichlorosilane, silicon tetrachloride, and hexachlorosilane), thereby effectively improving raw material utilization.
[0003] The process of cracking high-boiling-point compounds involves the hydrolysis of these compounds. Traditional high-boiling-point compound hydrolysis processes typically involve directly injecting the high-boiling-point compounds into a reaction solution (alkaline solution, usually sodium hydroxide solution) within a hydrolysis reactor for the hydrolysis reaction. Since the hydrolysis reaction of high-boiling-point compounds is a strongly exothermic process, it releases a large amount of heat and generates gases. In actual production operations, the structure of the hydrolysis reactor used for high-boiling-point compound hydrolysis is primarily limited to providing a reaction space and cannot withstand the increased pressure within the reactor.
[0004] This leads to a situation where, during actual production, when the hydrolysis reaction generates a large amount of heat and gas, if the exhaust pipe of the hydrolysis vessel cannot release these gases in time, the pressure inside the hydrolysis vessel will rise rapidly, thereby increasing the risk of the hydrolysis vessel exploding and posing a significant safety hazard to production equipment and operators.
[0005] In current operational practices, the reaction rate inside the hydrolysis reactor is mainly adjusted by controlling the feeding speed of high-boiling-point substances. However, the actual effectiveness of this method largely depends on the experience and skill level of the operators. This approach, which relies on human control, cannot fundamentally solve the problem of sudden pressure increases inside the hydrolysis reactor, making the safe operation of the equipment highly uncertain. Utility Model Content
[0006] The technical problem to be solved by this utility model is to address the above-mentioned deficiencies in the existing technology by providing a polycrystalline silicon high-boiling-point hydrolysis device and a polycrystalline silicon high-boiling-point treatment system. By setting a buffer layer, the contact rate between the polycrystalline silicon high-boiling-point substance and the reaction solution can be reduced, thereby reducing the reaction rate in the hydrolysis vessel and solving the problem of sudden pressure increase in the hydrolysis vessel.
[0007] In a first aspect, this utility model provides a polycrystalline silicon high-boiling-point hydrolysis device, which includes a hydrolysis vessel and a buffer layer. A feed pipe is provided at the top of the hydrolysis vessel. The buffer layer is located inside the hydrolysis vessel, floating and covering the upper surface of the reaction solution, and flow channels are formed within the buffer layer. The polycrystalline silicon high-boiling-point substance entering the hydrolysis vessel through the feed pipe flows through the flow channels of the buffer layer to the reaction solution and reacts with the reaction solution.
[0008] In some embodiments, the height of the internal space of the hydrolysis reactor is H; the thickness of the buffer layer is L, where 0.2H≤L≤0.25H.
[0009] In some embodiments, the distance between the upper surface of the buffer layer and the top wall of the hydrolysis vessel is h, where 0.1H ≤ h ≤ 0.5H.
[0010] In some embodiments, the buffer layer is formed by a plurality of floats arranged in multiple rows, and the gap between two adjacent floats in each row forms the flow channel of the buffer layer.
[0011] In some embodiments, the inner diameter of the hydrolysis vessel is D; the diameter of the float is d, where 0.06D≤d≤0.1D.
[0012] In some embodiments, a radar level gauge is also provided on the top of the hydrolysis vessel, the radar level gauge being used to detect the position of the upper surface of the buffer layer.
[0013] In some embodiments, the hydrolysis vessel is further provided with a stirring paddle, which is used to stir the materials in the hydrolysis vessel.
[0014] In some embodiments, the top of the hydrolysis vessel is also provided with an exhaust pipe, through which the waste gas generated after the reaction of the polycrystalline silicon high-boiling material and the reaction solution is discharged.
[0015] In some embodiments, the polysilicon high-boiling-point hydrolysis apparatus further includes a water-sealed tank; the outlet of the exhaust pipe extends below the liquid level inside the water-sealed tank.
[0016] Therefore, the polycrystalline silicon high-boiling-point hydrolysis device provided in this embodiment of the invention allows the polycrystalline silicon high-boiling-point substance to be injected into the hydrolysis vessel from the top by setting a feed pipe at the top of the hydrolysis vessel; by setting a buffer layer and making the buffer layer float and cover the upper surface of the reaction solution, the polycrystalline silicon high-boiling-point substance entering the hydrolysis vessel can first land on the upper surface of the buffer layer, avoiding the polycrystalline silicon high-boiling-point substance from falling directly into the reaction solution and reacting rapidly with the reaction solution; at the same time, by setting a flow channel in the buffer layer, the polycrystalline silicon high-boiling-point substance on the upper surface of the buffer layer can flow to the reaction solution through the flow channel, thus slowing down the contact rate between the polycrystalline silicon high-boiling-point substance and the reaction solution, allowing the polycrystalline silicon high-boiling-point substance to slowly contact and react with the reaction solution, thereby reducing the reaction rate between the polycrystalline silicon high-boiling-point substance and the reaction solution, reducing the rate of heat and gas generation during the reaction, allowing the gas pressure in the hydrolysis vessel to rise slowly, giving the hydrolysis vessel enough time to discharge the gas, solving the problem of sudden pressure increase in the hydrolysis vessel, and avoiding explosion caused by sudden pressure increase in the hydrolysis vessel.
[0017] Secondly, this utility model provides a polycrystalline silicon high-boiling-point treatment system, which includes a high-boiling-point tank, a reaction solution tank, a polycrystalline silicon high-boiling-point hydrolysis device as described in the first aspect, and a waste liquid collection device. The high-boiling-point tank is used to store polycrystalline silicon high-boiling-point substances. The reaction solution tank is used to store the reaction solution. The polycrystalline silicon high-boiling-point hydrolysis device is connected to both the high-boiling-point tank and the reaction solution tank. The waste liquid collection device is connected to the bottom of the hydrolysis vessel of the polycrystalline silicon high-boiling-point hydrolysis device and is used to collect the waste liquid generated after the reaction of the polycrystalline silicon high-boiling-point substances and the reaction solution in the hydrolysis vessel.
[0018] The polycrystalline silicon high-boiling-point treatment system provided in this embodiment of the invention has the same beneficial effects as the polycrystalline silicon high-boiling-point hydrolysis device described above, and will not be repeated here. Attached Figure Description
[0019] Figure 1 : A schematic diagram of a polycrystalline silicon high-boiling-point hydrolysis device provided in an embodiment of this utility model.
[0020] Among them, 1-feed pipe; 2-exhaust pipe; 3-water seal tank; 4-buffer layer; 5-stirring paddle; 6-drain valve; 7-radar level gauge; 8-hydrolysis kettle; 9-drain pipe. Detailed Implementation
[0021] To enable those skilled in the art to better understand the technical solution of this utility model, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments.
[0022] Example 1:
[0023] like Figure 1 As shown in the figure, this utility model embodiment provides a polycrystalline silicon high-boiling-point hydrolysis device, which is applied to the hydrolysis process of polycrystalline silicon high-boiling-point substances.
[0024] like Figure 1 As shown, the polycrystalline silicon high-boiling-point hydrolysis device includes a hydrolysis vessel 8 and a buffer layer 4. A feed pipe 1 is provided at the top of the hydrolysis vessel 8. The buffer layer 4 is located inside the hydrolysis vessel 8, floating and covering the upper surface of the reaction solution, and flow channels are formed within the buffer layer 4. The polycrystalline silicon high-boiling-point substance entering the hydrolysis vessel 8 through the feed pipe 1 flows through the flow channels of the buffer layer 4 to the reaction solution and reacts with the reaction solution (hydrolysis reaction).
[0025] Those skilled in the art will know that high-boiling polycrystalline silicon products can be mixtures of various substances, including trichlorosilane, silicon tetrachloride, and hexachlorosilane.
[0026] For example, the feed pipe 1 is connected to the external polysilicon high-boiling point supply pipe and the reaction solution supply pipe, and the polysilicon high-boiling point supply pipe and the reaction solution supply pipe can respectively deliver polysilicon high-boiling point and reaction solution into the hydrolysis vessel 8 through the feed pipe 1.
[0027] For example, the reaction solution described above is an alkaline solution, such as a sodium hydroxide solution.
[0028] For example, when high-boiling polycrystalline silicon reacts with sodium hydroxide solution, the main gas produced is hydrogen chloride gas, the by-product gas is hydrogen gas, and the liquid phase after the reaction is mainly sodium silicate and sodium chloride.
[0029] In some examples, such as Figure 1 As shown, the top of the hydrolysis vessel 8 is also equipped with an exhaust pipe 2, through which the waste gas generated after the reaction of the polycrystalline silicon high-boiling material and the reaction solution is discharged.
[0030] The aforementioned waste gases are hydrogen chloride gas and hydrogen gas.
[0031] By discharging the aforementioned waste gas, the total amount of gas in the hydrolysis reactor 8 can be reduced, thus preventing an increase in pressure inside the hydrolysis reactor 8 due to excessive gas and reducing the risk of explosion.
[0032] In some examples, such as Figure 1 As shown, the polycrystalline silicon high-boiling-point hydrolysis device also includes a water-sealed tank 3. The outlet of the exhaust pipe 2 extends below the liquid level inside the water-sealed tank 3.
[0033] Water seal tank 3 adopts an existing water seal tank, so its structure and working principle are existing technologies.
[0034] For example, the liquid in the water seal tank 3 is an alkaline solution (e.g., sodium hydroxide solution) or pure water.
[0035] The liquid inside the water seal tank 3 can neutralize and absorb hydrogen chloride gas in the exhaust gas, preventing hydrogen chloride gas from polluting the environment.
[0036] Understandably, the density of the buffer layer 4 is less than the density of the liquid (including the reaction solution, liquid phase substances during or after the reaction) in the water seal tank 3. Furthermore, the material of the buffer layer 4 does not react with the substances (including high-boiling polycrystalline silicon, the reaction solution, liquid phase substances during or after the reaction) in the hydrolysis vessel 8. For example, the material of the buffer layer 4 can be polypropylene, polytetrafluoroethylene, or polyvinylidene fluoride, etc.
[0037] The shape and direction of the flow channel are not restricted, as long as it allows high-boiling polycrystalline silicon to pass through.
[0038] For example, the extension direction of the flow channel can be vertical, or the shape of the flow channel can be a broken line or an arc, etc.
[0039] For example, the buffer layer 4 can have multiple channels, which are evenly distributed on the upper surface of the buffer layer 4. The inner diameter of the channel is much smaller than the inner diameter of the feed pipe 1 (for example, the inner diameter of the channel is less than or equal to one-tenth of the inner diameter of the feed pipe 1).
[0040] like Figure 1 As shown, in the process of using the polycrystalline silicon high-boiling-point hydrolysis device, the reaction solution is first introduced into the hydrolysis vessel 8 through the feed pipe 1, and then the buffer layer 4 is placed, at which time the buffer layer 4 will float on top of the reaction solution. Then, the polycrystalline silicon high-boiling-point substance is introduced into the hydrolysis vessel 8 through the feed pipe 1.
[0041] like Figure 1 As shown, after the high-boiling polycrystalline silicon compound enters the hydrolysis reactor 8, it first falls onto the buffer layer 4 and disperses. At this time, the buffer layer 4 acts as a liquid distributor, allowing the high-boiling polycrystalline silicon compound to be evenly dispersed on the entire surface of the buffer layer 4 before flowing into the reaction solution through the channels on the buffer layer 4. This reduces the instantaneous contact area between the high-boiling polycrystalline silicon compound and the reaction solution, thus preventing the high-boiling polycrystalline silicon compound from falling directly into the reaction solution and reacting rapidly. Therefore, it slows down the contact rate between the high-boiling polycrystalline silicon compound and the reaction solution, allowing them to slowly contact and react. This reduces the reaction rate between the high-boiling polycrystalline silicon compound and the reaction solution, lowers the rate of heat and gas generation during the reaction, and allows the gas pressure inside the hydrolysis reactor 8 to rise slowly, preventing a sudden increase in gas pressure inside the hydrolysis reactor 8 that could lead to an explosion.
[0042] In addition, the buffer layer 4 can occupy part of the space inside the hydrolysis vessel 8. When the same reaction solution is introduced, the volume of the gas space inside the hydrolysis vessel 8 can be reduced compared with the absence of the buffer layer 4, which in turn reduces the total amount of gas inside the hydrolysis vessel 8.
[0043] According to the ideal gas law: V = nRT / P, where V represents the gas volume (m³), n represents the amount of substance of the gas (mol), R represents the ideal gas constant (8.314 J / (mol·K)), T represents the thermodynamic temperature of the gas (K), and P represents the gas pressure (Pa). Under the same temperature change, the change in gas volume is only related to the amount of substance in the gas (i.e., the total amount of gas). When the temperature inside the hydrolysis reactor 8 rises, after reducing the total amount of gas inside the hydrolysis reactor 8, the change in the gas expansion volume inside the hydrolysis reactor 8 also decreases. The exhaust pipe 2 can then promptly discharge the expanded gas, alleviating the high-pressure risk inside the hydrolysis reactor 8 and preventing an explosion.
[0044] The buffer layer 4 also has a certain isolation effect. The heat generated by the reaction between the high-boiling polysilicon and the reaction solution is isolated in the area below the buffer layer 4, which reduces the heating rate of the gas in the area above the buffer layer 4 in the hydrolysis vessel 8 by the heat generated by the reaction between the high-boiling polysilicon and the reaction solution. This reduces the rate at which the gas in the hydrolysis vessel 8 expands due to the increase in temperature, and thus reduces the rate at which the gas pressure in the hydrolysis vessel 8 increases. This allows the hydrolysis vessel 8 enough time to discharge the gas, preventing a sudden increase in gas pressure in the hydrolysis vessel 8 and thus avoiding an explosion.
[0045] The buffer layer 4 also has a shielding function, which can reduce the evaporation and splashing of liquid generated when polycrystalline silicon high boiling material reacts with the reaction solution, thereby reducing the phenomenon of liquid entrainment in the gas discharged from the exhaust pipe 2.
[0046] Therefore, the polycrystalline silicon high-boiling-point hydrolysis apparatus provided in this embodiment of the invention allows the polycrystalline silicon high-boiling-point substance to be injected into the hydrolysis vessel 8 from the top by providing a feed pipe 1 at the top of the hydrolysis vessel 8; by providing a buffer layer 4, which floats and covers the upper surface of the reaction solution, the polycrystalline silicon high-boiling-point substance entering the hydrolysis vessel 8 first falls onto the upper surface of the buffer layer 4, preventing it from falling directly into the reaction solution and reacting rapidly; simultaneously, by providing a buffer layer (flow channel) within the buffer layer 4, The high-boiling point of polycrystalline silicon on the upper surface of the buffer layer 4 can flow into the reaction solution through the flow channel, thus slowing down the contact rate between the high-boiling point of polycrystalline silicon and the reaction solution. This allows the high-boiling point of polycrystalline silicon to slowly contact and react with the reaction solution, thereby reducing the reaction rate between the high-boiling point of polycrystalline silicon and the reaction solution. This reduces the rate of heat and gas generation during the reaction, allowing the gas pressure inside the hydrolysis vessel 8 to rise slowly. This gives the hydrolysis vessel 8 enough time to discharge the gas, solving the problem of sudden pressure increase inside the hydrolysis vessel 8 and preventing an explosion caused by a sudden increase in gas pressure inside the hydrolysis vessel 8.
[0047] In some embodiments, such as Figure 1 As shown, the height of the internal space of the hydrolysis vessel 8 is H. The thickness of the buffer layer 4 is L, where 0.2H ≤ L ≤ 0.25H.
[0048] For example, when the height H of the internal space of the hydrolysis vessel 8 is 2m, 0.4m≤L≤0.5m, the thickness L of the buffer layer 4 can be 0.4m, 0.45m or 0.5m, etc.
[0049] Through the above settings, the thickness of the buffer layer 4 can be kept within a reasonable range, and the buffer layer 4 can occupy a certain space in the hydrolysis vessel 8 to reduce the total amount of gas in the hydrolysis vessel 8; and the above settings can ensure the insulation capability of the buffer layer 4 over the heat below it, and improve the shielding effect against liquid evaporation and splashing generated when polycrystalline silicon high-boiling material reacts with the reaction solution.
[0050] In some embodiments, such as Figure 1 As shown, the distance between the upper surface of the buffer layer 4 and the top wall of the hydrolysis vessel 8 is h, where 0.1H≤h≤0.5H.
[0051] For example, when the height H of the internal space of the hydrolysis vessel 8 is 2m, 0.2m≤h≤1m, the distance h between the upper surface of the buffer layer 4 and the top wall of the hydrolysis vessel 8 can be 0.2m, 0.5m or 1m, etc.
[0052] With the above settings, the space above the buffer layer 4 can accommodate the gas generated when polycrystalline silicon high-boiling material reacts with the reaction solution, and form a safe space in the hydrolysis vessel 8 to prevent the material in the hydrolysis vessel 8 from overflowing during the reaction.
[0053] In some embodiments, such as Figure 1 As shown, the buffer layer 4 is formed by multiple floats, which are arranged in multiple rows. The gap between two adjacent floats in each row forms the flow channel of the buffer layer 4.
[0054] For example, the float can be a solid float or a hollow float. The average density of the float is less than the density of the liquid (including the reaction solution, liquid phase substances during or after the reaction) in the water seal tank 3; and the material of the float can be chosen to not react with the substances (including high-boiling polycrystalline silicon, reaction solution, liquid phase substances during or after the reaction) in the hydrolysis vessel 8, for example, the material can be polypropylene, polytetrafluoroethylene, or polyvinylidene fluoride, etc.
[0055] In the actual production process, the number of rows of multiple floats arranged vertically and the number of floats in each row can be flexibly set according to the total height of the internal space of the hydrolysis vessel 8, the thickness L of the buffer layer 4, and the size of the floats themselves.
[0056] For example, multiple floats are arranged in three rows, with 90 floats in each row.
[0057] With the dimensions of the hydrolysis vessel 8 remaining constant, changes in the dimensions of the floats themselves will lead to changes in the number of rows formed by the multiple floats and the number of floats in each row.
[0058] like Figure 1 As shown, in the multi-row floats, irregular small gaps will be formed between the floats that are in contact with each other, thus forming flow channels in the buffer layer 4.
[0059] After the high-boiling polycrystalline silicon substance enters the hydrolysis vessel 8 and lands on the float, it will slowly seep into the reaction solution along the outer surface of the float and through the gap between two adjacent floats. This can slow down the contact rate between the high-boiling polycrystalline silicon substance and the reaction solution. Compared with not setting floats, it can avoid the high-boiling polycrystalline silicon substance from directly contacting the reaction solution and reacting rapidly, thereby avoiding the generation of too much heat and gas during rapid reaction, which could lead to the explosion of the hydrolysis vessel 8.
[0060] Multiple floats can adapt to changes in the liquid level inside the hydrolysis vessel 8 and give the formed buffer layer 4 good deformation capability. Therefore, forming the buffer layer 4 with multiple floats has the advantage of convenient operation.
[0061] In some embodiments, the inner diameter of the hydrolysis vessel 8 is D; the diameter of the float is d, where 0.06D≤d≤0.1D.
[0062] For example, when the inner diameter D of the hydrolysis vessel 8 is 1m, then 0.06m≤d≤0.1m. For instance, the diameter d of the float can be 0.06m, 0.08m, or 0.1m, etc.
[0063] The inventors discovered that by setting the float diameter d to the above range, the number of floats in each row can be limited, thereby maintaining the number of flow channels formed between adjacent floats at a reasonable level. This allows multiple rows of floats to better slow down the contact rate between the high-boiling polycrystalline silicon and the reaction solution.
[0064] In some embodiments, such as Figure 1 As shown, a radar level gauge 7 is also installed on the top of the hydrolysis vessel 8. The radar level gauge 7 is used to detect the position of the upper surface of the buffer layer 4.
[0065] Understandably, the buffer layer 4 floats on the upper surface of the reaction solution. When the liquid level of the reaction solution changes, the change in the thickness of the buffer layer 4 is negligible. Therefore, after obtaining the position of the upper surface of the buffer layer 4 through the radar level gauge 7, the thickness of the buffer layer 4 can be subtracted to obtain the liquid level height of the reaction solution.
[0066] With the above settings, the liquid level of the reaction solution inside the hydrolysis reactor 8 can be monitored in real time.
[0067] In some embodiments, such as Figure 1As shown, a stirring paddle 5 is also provided inside the hydrolysis vessel 8, which is used to stir the materials inside the hydrolysis vessel 8.
[0068] Understandably, the agitator 5 can be driven by an external drive unit (such as a motor).
[0069] When polycrystalline silicon high-boiling material reacts with the reaction solution, the stirring of the stirring paddle 5 can make the polycrystalline silicon high-boiling material and the reaction solution fully mixed, improve the reaction efficiency, and promptly remove the gas generated during the reaction. The stirring of the stirring paddle 5 can also make the heat generated during the reaction of polycrystalline silicon high-boiling material and reaction solution evenly distributed, avoiding heat accumulation in some areas inside the hydrolysis vessel 8.
[0070] In some examples, such as Figure 1 As shown, a drain pipe 9 and a drain valve 6 are also provided at the bottom of the hydrolysis reactor 8. The drain pipe 9 is used to discharge the waste liquid in the hydrolysis reactor 8, and the drain valve 6 is used to control the opening and closing of the drain pipe 9.
[0071] The working process of the polysilicon high-boiling-point hydrolysis device is illustrated below:
[0072] First, inject an appropriate amount (e.g., half the amount required for each reaction) of alkaline solution (i.e., reaction solution, here sodium hydroxide solution) into the hydrolysis reactor 8. Then, place floats to form a buffer layer 4, and continue to circulate alkaline solution to raise all the floats in the buffer layer 4 to the target height (set according to the actual reaction requirements). During this process, the radar level gauge 7 is used to monitor the position of the uppermost float, thereby monitoring the alkaline solution level in the hydrolysis reactor 8 in real time. Start the agitator 5 to stir the liquid (alkaline solution) in the hydrolysis reactor 8 at a constant speed in real time.
[0073] High-boiling-point polycrystalline silicon is injected into the hydrolysis reactor 8 through the feed pipe 1. The polycrystalline silicon slowly seeps down through the buffer layer 4, gradually contacting the alkaline solution in the hydrolysis reactor 8 and undergoing a hydrolysis reaction. The main gas produced is hydrogen chloride gas, and the byproduct gas is hydrogen gas. The liquid phase (waste liquid) after the reaction mainly consists of sodium silicate and sodium chloride. The gaseous products are transferred to the water seal tank 3 through the exhaust pipe 2, where the hydrogen chloride gas is absorbed, and the remaining hydrogen gas is discharged from the water seal tank 3. At the end of the reaction, the stirring paddle 5 is stopped, and the drain valve 6 is opened, allowing the liquid phase after the reaction to be discharged through the drain pipe 9 at the bottom of the hydrolysis reactor 8.
[0074] Before starting the next batch of hydrolysis reaction, close the drain valve 6 and inject alkali solution again through the feed pipe 1. Observe the liquid level of the radar level gauge 7. When the liquid level reaches the safe height (set according to the actual reaction requirements), start the agitator 5 again to stir slowly. At this time, the alkali solution can rinse all the floats in the buffer layer 4, which can play a role in cleaning the floats. When the radar level gauge 7 monitors that the floats have risen to the target height, add polycrystalline silicon high-boiling material to start the next batch of reaction.
[0075] Example 2:
[0076] This utility model embodiment also provides a polycrystalline silicon high-boiling-point substance treatment system for treating polycrystalline silicon high-boiling-point substances generated during polycrystalline silicon production. The polycrystalline silicon high-boiling-point substance treatment system includes a high-boiling-point tank, a reaction solution tank, a polycrystalline silicon high-boiling-point substance hydrolysis device, and a waste liquid collection device. The high-boiling-point tank is used to store the polycrystalline silicon high-boiling-point substances. The reaction solution tank is used to store the reaction solution, which may specifically be a sodium hydroxide solution. The polycrystalline silicon high-boiling-point substance hydrolysis device is connected to both the high-boiling-point tank and the reaction solution tank. The waste liquid collection device is connected to the bottom of the hydrolysis vessel 8 of the polycrystalline silicon high-boiling-point hydrolysis device and is used to collect the waste liquid generated after the reaction of the polycrystalline silicon high-boiling-point substances and the reaction solution in the hydrolysis vessel 8.
[0077] For example, the high-boiling tank is connected to the feed pipe 1 of the hydrolysis vessel 8 through a first pipe, and the reaction solution tank is connected to the feed pipe 1 of the hydrolysis vessel 8 through a second pipe. By controlling the opening and closing of the first and second pipes respectively (e.g., through valves), polycrystalline silicon high-boiling and sodium hydroxide solutions can be delivered into the hydrolysis vessel 8 respectively.
[0078] Those skilled in the art will know that high-boiling polycrystalline silicon products can be mixtures of various substances, including trichlorosilane, silicon tetrachloride, and hexachlorosilane.
[0079] Waste liquid collection devices can be existing tanks or water tanks, etc.
[0080] For example, the waste liquid collection device is connected to the bottom of the hydrolysis vessel 8 through the drain pipe 9 at the bottom of the hydrolysis vessel 8.
[0081] The above settings can be used to treat high-boiling-point polycrystalline silicon and solve the problem of sudden pressure increase in the hydrolysis vessel 8 when high-boiling-point polycrystalline silicon reacts rapidly with sodium hydroxide solution. This avoids explosion caused by sudden pressure increase in the hydrolysis vessel 8 and improves the safety of the high-boiling-point polycrystalline silicon treatment system.
[0082] It is understood that the above embodiments are merely exemplary implementations used to illustrate the principles of this utility model, and the utility model 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 this utility model, and these modifications and improvements are also considered to be within the protection scope of this utility model.
Claims
1. A device for hydrolyzing high-boiling polycrystalline silicon, characterized in that, include: Hydrolysis vessel (8), with a feed pipe (1) at its top; and, A buffer layer (4) is located inside the hydrolysis vessel (8) and floats and covers the upper surface of the reaction solution. A flow channel is formed inside the buffer layer (4). The high-boiling polycrystalline silicon material entering the hydrolysis vessel (8) through the feed pipe (1) flows through the buffer layer (4) to the reaction solution and reacts with the reaction solution.
2. The polycrystalline silicon high-boiling-point hydrolysis apparatus according to claim 1, characterized in that, The height of the internal space of the hydrolysis vessel (8) is H; The thickness of the buffer layer (4) is L, where 0.2H ≤ L ≤ 0.25H.
3. The polycrystalline silicon high-boiling-point hydrolysis apparatus according to claim 2, characterized in that, The distance between the upper surface of the buffer layer (4) and the top wall of the hydrolysis vessel (8) is h, where 0.1H≤h≤0.5H.
4. The polycrystalline silicon high-boiling-point hydrolysis apparatus according to claim 1, characterized in that, The buffer layer (4) is formed by multiple floats, which are arranged in multiple rows. The gap between two adjacent floats in each row forms the flow channel of the buffer layer (4).
5. The polycrystalline silicon high-boiling-point hydrolysis apparatus according to claim 4, characterized in that, The inner diameter of the hydrolysis vessel (8) is D; The diameter of the float is d, where 0.06D≤d≤0.1D.
6. The polycrystalline silicon high-boiling-point hydrolysis apparatus according to claim 1, characterized in that, The top of the hydrolysis vessel (8) is also equipped with a radar level gauge (7), which is used to detect the position of the upper surface of the buffer layer (4).
7. The polycrystalline silicon high-boiling-point hydrolysis apparatus according to claim 1, characterized in that, The hydrolysis vessel (8) is also equipped with a stirring paddle (5), which is used to stir the material in the hydrolysis vessel (8).
8. The polycrystalline silicon high-boiling-point hydrolysis apparatus according to claim 1, characterized in that, The top of the hydrolysis vessel (8) is also provided with an exhaust pipe (2), through which the waste gas generated after the polycrystalline silicon high boiling point reacts with the reaction solution is discharged.
9. The polycrystalline silicon high-boiling-point hydrolysis apparatus according to claim 8, characterized in that, It also includes a water seal tank (3); The outlet of the exhaust pipe (2) extends below the liquid level inside the water seal tank (3).
10. A polycrystalline silicon high-boiling-point treatment system, characterized in that, include: High-boiling-point tanks are used to store high-boiling-point polycrystalline silicon. A reaction solution container is used to store reaction solutions. The polycrystalline silicon high-boiling-point hydrolysis apparatus according to any one of claims 1-9 is connected to both the high-boiling-point tank and the reaction solution tank; and, The waste liquid collection device is connected to the bottom of the hydrolysis vessel (8) of the polycrystalline silicon high-boiling-point hydrolysis device, and is used to collect the waste liquid generated after the polycrystalline silicon high-boiling-point and the reaction solution react in the hydrolysis vessel (8).