Polycrystalline silicon reduction furnace electrode cooling device, polycrystalline silicon reduction furnace and polycrystalline silicon production device

Abstract

The utility model discloses a polycrystalline silicon reduction furnace electrode cooling device and a polycrystalline silicon production system. The polycrystalline silicon reduction furnace electrode cooling device comprises a polycrystalline silicon reduction furnace electrode, an air cooler and a circulating pump which are communicated with one another through pipelines, wherein the pipeline is used for being filled with a heat-conducting medium, the circulating pump is used for driving the heat-conducting medium to circulate in the pipeline, and the air cooler is used for cooling the circulating heat-conducting medium. The polycrystalline silicon reduction furnace electrode cooling device provided by the utility model has the characteristics of lower investment and operation cost.

Description

Technical Field

[0001] This utility model relates to an electrode cooling device for a polycrystalline silicon reduction furnace and a polycrystalline silicon production system, belonging to the field of applied chemical engineering. Background Technology

[0002] Currently, the mainstream polysilicon production process in China adopts the modified Siemens process. In the reduction section, hydrogen is used to reduce gaseous trichlorosilane, and chemical vapor deposition is performed on the silicon core within the reduction furnace to generate rod-shaped polysilicon. During polysilicon production, to maintain the reaction temperature and protect the reduction furnace equipment, circulating demineralized water is typically used to cool the furnace cylinder, chassis, electrodes, and gaskets. The electrode system cooling temperature is usually 35-45℃. Conventional projects use a combination of open cooling towers / air cooling and evaporative cooling. However, this cooling method suffers from high investment and operating costs, and poor system regulation capabilities.

[0003] Therefore, developing an electrode cooling device for polycrystalline silicon reduction furnaces with lower investment and operating costs and stronger system regulation capabilities has become a research direction. Utility Model Content

[0004] This invention provides an electrode cooling device for a polycrystalline silicon reduction furnace, which features low investment and operating costs.

[0005] This invention also provides a polycrystalline silicon reduction furnace, which has the characteristics of low investment and operating costs.

[0006] This invention also provides a polysilicon production apparatus, which features low investment and operating costs.

[0007] This utility model provides a polycrystalline silicon reduction furnace electrode cooling device, which includes a polycrystalline silicon reduction furnace electrode, an air cooler, and a circulating pump that are interconnected by pipes.

[0008] The pipe is used to fill the heat-conducting medium, the circulating pump is used to drive the heat-conducting medium to circulate in the pipe, and the air cooler is used to cool the heat-conducting medium in the circulation.

[0009] The polysilicon reduction furnace electrode cooling device described above further includes a heat transfer medium storage tank, which is connected to the polysilicon reduction furnace electrode, air cooler, and circulating pump via the pipeline.

[0010] In the polycrystalline silicon reduction furnace electrode cooling device described above, the heat-conducting medium is deionized water.

[0011] In the polycrystalline silicon reduction furnace electrode cooling device described above, the operating temperature of the heat-conducting medium is 45~65℃.

[0012] The polycrystalline silicon reduction furnace electrode cooling device described above further includes a heat transfer medium replenishment device connected to the heat transfer medium storage tank.

[0013] In the polycrystalline silicon reduction furnace electrode cooling device described above, the circulating pump is a variable frequency pump.

[0014] The polysilicon reduction furnace electrode cooling device described above, wherein a first thermometer is provided at the inlet of the polysilicon reduction furnace electrode heat-conducting medium flow;

[0015] The electrode cooling device for the polycrystalline silicon reduction furnace also includes a controller;

[0016] The circulating pump and the first thermometer are electrically connected to the controller.

[0017] The polysilicon reduction furnace electrode cooling device described above, wherein a second thermometer is provided at the outlet of the polysilicon reduction furnace electrode heat-conducting medium flow;

[0018] The second thermometer is electrically connected to the controller.

[0019] This utility model also provides a polycrystalline silicon reduction furnace, which includes any of the above-mentioned polycrystalline silicon reduction furnace electrode cooling devices.

[0020] This utility model also provides a polysilicon production apparatus, which includes the above-mentioned polysilicon reduction furnace; or, includes any of the above-mentioned polysilicon reduction furnace electrode cooling devices.

[0021] The electrode cooling device for polycrystalline silicon reduction furnace provided by this utility model has the characteristics of low investment and operating costs. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced one by one below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 A schematic diagram of the structure of the first type of electrode cooling device for polycrystalline silicon reduction furnace provided by this utility model;

[0024] Figure 2 A schematic diagram of the structure of the second type of electrode cooling device for polycrystalline silicon reduction furnace provided by this utility model;

[0025] Figure 3A schematic diagram of the structure of the third type of electrode cooling device for polycrystalline silicon reduction furnace provided by this utility model;

[0026] Figure 4 A schematic diagram of the structure of the fourth type of electrode cooling device for polycrystalline silicon reduction furnace provided by this utility model;

[0027] Figure 5 A schematic diagram of the structure of the fifth type of electrode cooling device for polycrystalline silicon reduction furnace provided by this utility model.

[0028] Explanation of reference numerals in the attached figures:

[0029] A-Polycrystalline silicon reduction furnace electrode;

[0030] B-Air cooler;

[0031] C-Circulation Pump;

[0032] D-Heat transfer medium storage tank;

[0033] E-Heat transfer medium replenishment device;

[0034] F - First thermometer;

[0035] G - Second thermometer;

[0036] H-pipe. Detailed Implementation

[0037] To enable those skilled in the art to better understand the present invention, a further detailed description of the present invention is provided below. The specific embodiments listed below are merely descriptions of the principles and features of the present invention, and the examples are only used to explain the present invention and are not intended to limit its scope. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the protection scope of the present invention.

[0038] The first aspect of this utility model provides a polysilicon reduction furnace electrode cooling device, which includes a polysilicon reduction furnace electrode, a B-air cooler, and a C-circulation pump that are interconnected through an H-pipe.

[0039] Among them, H-pipe is used to fill the heat transfer medium, C-circulation pump is used to drive the heat transfer medium to circulate in H-pipe, and B-air cooler is used to cool the heat transfer medium in circulation.

[0040] Figure 1 A schematic diagram of the structure of the first type of electrode cooling device for a polycrystalline silicon reduction furnace provided by this utility model. Figure 1As shown, the device includes an A-polysilicon reduction furnace electrode, a B-air cooler, and a C-circulating pump, all interconnected via an H-pipe. Specifically, the circulating pump's outlet is connected to the heat transfer medium inlet of the reduction furnace electrode, the polysilicon reduction furnace electrode's outlet is connected to the heat transfer medium inlet of the B-air cooler, and the B-air cooler's outlet is connected to the circulating pump's inlet. This invention does not limit the connection order of the above devices; the devices only need to meet the requirement of being interconnected via the H-pipe.

[0041] The A-polysilicon reduction furnace electrode is one of the components of the polysilicon reduction furnace. The electrode assembly has a cavity through which a heat-conducting medium can pass, and it has a heat-conducting medium inlet and an outlet. The heat-conducting medium enters the A-polysilicon reduction furnace electrode through the heat-conducting medium inlet, absorbs heat from the A-polysilicon reduction furnace electrode, and then exits through the heat-conducting medium outlet, thus completing the cooling of the A-polysilicon reduction furnace electrode.

[0042] The B-air cooler has a cavity containing a heat-conducting medium. Through heat exchange with the air outside the cavity, the heat contained in the heat-conducting medium is transferred to the air, thus cooling the heat-conducting medium within the B-air cooler. The C-circulation pump drives the heat-conducting medium to circulate in the H-pipe between the A-polycrystalline silicon reduction furnace electrode and the B-air cooler, completing the cycle of heating the heat-conducting medium in the A-polycrystalline silicon reduction furnace electrode and cooling it in the B-air cooler. This invention does not limit the specific model of the B-air cooler; any commonly used B-air cooler in the art can be selected, as long as it can transfer the heat contained in the heat-conducting medium to the air.

[0043] This invention does not limit the choice of heat-conducting medium; commonly used heat-conducting media in the art can be used. In one embodiment, the heat-conducting medium can be selected from either water or heat-conducting oil.

[0044] In existing technologies, a combination of open cooling towers / air cooling and evaporative cooling is commonly used to cool the electrodes of A-polycrystalline silicon reduction furnaces, resulting in high equipment investment and operating costs. The inventors have discovered that using a B-air cooler to cool the electrodes of A-polycrystalline silicon reduction furnaces significantly reduces investment costs compared to existing technologies due to the lower size and investment required for the air cooling system. Furthermore, since this cooling device consumes no water and discharges no wastewater, the polycrystalline silicon reduction furnace electrode cooling device provided by this invention offers advantages in both low operating costs and good environmental performance.

[0045] This invention provides an electrode cooling device for a polycrystalline silicon reduction furnace, which features low investment and operating costs.

[0046] Figure 2This is a schematic diagram of the structure of the second type of electrode cooling device for a polycrystalline silicon reduction furnace provided by this utility model. Figure 2 As shown, the device also includes a D-heat transfer medium storage tank, which is interconnected with the A-polycrystalline silicon reduction furnace electrode, the B-air cooler, and the C-circulation pump via an H-pipe.

[0047] The D-heat-conducting medium storage tank is used to store heat-conducting medium, enabling the polycrystalline silicon reduction furnace electrode cooling device provided by this utility model to have higher cooling efficiency.

[0048] This utility model does not limit the specific location of the D-heat-conducting medium storage tank, as long as it meets the requirement of being interconnected with the A-polycrystalline silicon reduction furnace electrode, B-air cooler and C-circulation pump through the H-pipe.

[0049] In one embodiment, the heat transfer medium is deionized water. Deionized water has a lower cost and a higher specific heat capacity, and when used in the polycrystalline silicon reduction furnace electrode cooling device provided by this invention, it can enable the device to have higher cooling efficiency.

[0050] In one embodiment, the operating temperature of the heat-conducting medium in the polycrystalline silicon reduction furnace electrode cooling device provided by this invention is 45-65℃. Specifically, before entering the A-polycrystalline silicon reduction furnace electrode for heat exchange, the temperature of the heat-conducting medium is 45-50℃; after heat exchange, the temperature of the heat-conducting medium leaving the A-polycrystalline silicon reduction furnace electrode is 60-65℃. Because there is a significant temperature difference between the above operating temperature and the ambient temperature, the above operating temperature can be further matched to the ambient temperature, enabling the polycrystalline silicon reduction furnace electrode cooling device provided by this invention to have higher cooling efficiency.

[0051] Figure 3 This is a schematic diagram of the structure of the third type of electrode cooling device for a polycrystalline silicon reduction furnace provided by this utility model. Figure 3 As shown, the polycrystalline silicon reduction furnace electrode cooling device provided by this utility model also includes an E-thermal conductive medium replenishment device connected to the D-thermal conductive medium storage tank. The E-thermal conductive medium replenishment device is used to replenish the thermal conductive medium to the polycrystalline silicon reduction furnace electrode cooling device. When the thermal conductive medium leaks, the E-thermal conductive medium replenishment device can replenish the thermal conductive medium to the polycrystalline silicon reduction furnace electrode cooling device, thereby ensuring the cooling effect of the polycrystalline silicon reduction furnace electrode cooling device provided by this utility model.

[0052] This invention does not limit the specific equipment selection for the E-heat transfer medium replenishment device, and can be determined according to different heat transfer media. In one embodiment, when the heat transfer medium is demineralized water, the E-heat transfer medium replenishment device is a demineralized water interface in the plant area.

[0053] Furthermore, in one embodiment, in the polycrystalline silicon reduction furnace electrode cooling device provided by this utility model, the C-circulation pump is a variable frequency pump. The variable frequency pump can adjust the flow rate of the heat transfer medium entering the A-polycrystalline silicon reduction furnace electrode for heat exchange by changing the flow rate of the heat transfer medium, thereby enhancing the adjustability of the polycrystalline silicon reduction furnace electrode cooling device. It can adjust the heat transfer medium according to the actual production load, making the energy-saving and consumption-reducing advantages of the polycrystalline silicon reduction furnace electrode cooling device provided by this utility model even more prominent.

[0054] Figure 4 This is a schematic diagram of the structure of the fourth type of electrode cooling device for a polycrystalline silicon reduction furnace provided by this utility model. Figure 4 As shown, the inlet of the electrode heat-conducting medium in the polycrystalline silicon reduction furnace is equipped with an F-first thermometer;

[0055] The electrode cooling device for the polysilicon reduction furnace also includes a controller;

[0056] C-circulating pump and F-first thermometer are electrically connected to the controller.

[0057] F-The first thermometer is used to detect the temperature T1 of the heat transfer medium entering the A-polysilicon reduction furnace electrode. When T1 is detected to be higher than a preset value, the controller controls the C-circulation pump to increase the flow rate, allowing a larger flow of heat transfer medium to enter the A-polysilicon reduction furnace electrode, increasing the circulation speed of the heat transfer medium and improving the heat dissipation capacity of the polysilicon reduction furnace electrode cooling device. This invention does not limit the preset value of T1; in one embodiment, the preset value of T1 is 55°C.

[0058] Figure 5 This is a schematic diagram of the structure of the fifth type of electrode cooling device for a polycrystalline silicon reduction furnace provided by this utility model. Figure 5 As shown, the outlet of the electrode heat transfer medium in the polycrystalline silicon reduction furnace is equipped with a second thermometer (G-).

[0059] G - The second thermometer is electrically connected to the controller.

[0060] F-The first thermometer is used to detect the temperature T2 of the heat transfer medium leaving the A-polycrystalline silicon reduction furnace electrode. When T2 is detected to be higher than a preset value, the controller controls the variable frequency pump to increase the flow rate, allowing a larger flow of heat transfer medium to enter the A-polycrystalline silicon reduction furnace electrode, increasing the circulation speed of the heat transfer medium and improving the heat dissipation capacity of the polycrystalline silicon reduction furnace electrode cooling device. This invention does not limit the preset value of T2; in one embodiment, the preset value of T2 is 70°C.

[0061] Furthermore, in one embodiment, when T1 or T2 is detected to be higher than a preset value, the controller can control the variable frequency pump to increase the flow rate, allowing a larger flow rate of heat transfer medium to enter the A-polycrystalline silicon reduction furnace electrode, increasing the circulation speed of the heat transfer medium and improving the heat dissipation capacity of the polycrystalline silicon reduction furnace electrode cooling device.

[0062] The second aspect of this invention provides a polycrystalline silicon reduction furnace, which includes the electrode cooling device for the polycrystalline silicon reduction furnace provided in the first aspect of this invention. The polycrystalline silicon reduction furnace provided in the second aspect of this invention features lower investment and operating costs.

[0063] The third aspect of this utility model provides a polysilicon production apparatus, which includes the polysilicon reduction furnace provided in the second aspect of this utility model, or includes the electrode cooling device for the polysilicon reduction furnace provided in the first aspect of this utility model. The polysilicon production apparatus provided by this utility model has the advantages of low investment and operating costs.

[0064] The following examples further illustrate the electrode cooling device for the polycrystalline silicon reduction furnace provided by this utility model.

[0065] Example

[0066] This embodiment uses Figure 5 The electrode cooling device shown in the polycrystalline silicon reduction furnace cools the electrodes.

[0067] like Figure 5 As shown, the polysilicon reduction furnace electrode cooling device includes A-polysilicon reduction furnace electrode, B-air cooler, D-heat transfer medium storage tank and variable frequency pump (i.e., C-circulation pump) interconnected by H-pipe. The inlet of the polysilicon reduction furnace electrode heat transfer medium is equipped with F-first thermometer, and the outlet of the polysilicon reduction furnace electrode heat transfer medium is equipped with G-second thermometer. The heat transfer medium is deionized water. D-heat transfer medium storage tank is connected to the plant's demineralized water interface (i.e., E-heat transfer medium replenishment device). In addition, a controller (not shown) is also provided, which is electrically connected to F-first thermometer, G-second thermometer and variable frequency pump respectively.

[0068] When the above device is running, the variable frequency pump drives the deionized water to flow in the H-pipe. After absorbing heat from the A-polycrystalline silicon reduction furnace electrode, the temperature rises. Then it enters the B-air cooler, which transfers the heat to the air, thereby lowering the temperature of the deionized water. After passing through the D-thermal medium storage tank, it is circulated again by the variable frequency pump.

[0069] Meanwhile, when the F-first thermometer detects a temperature higher than 55℃, or the G-second thermometer detects a temperature higher than 70℃, the controller controls the frequency converter pump to increase the flow rate of deionized water, so that the deionized water can better cool the A-polycrystalline silicon reduction furnace electrode.

[0070] In the description of the embodiments of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, an indirect connection through an intermediate medium, or 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 application according to the specific circumstances.

[0071] The terms “first,” “second,” “third,” “fourth,” etc. (if present) in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a particular order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented, for example, in orders other than those illustrated or described herein. Furthermore, the terms “comprising” and “having,” and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0072] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and not to limit it. Although the utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the technical solutions of the embodiments of this utility model.

Claims

1. An electrode cooling device for a polycrystalline silicon reduction furnace, characterized in that, This includes polycrystalline silicon reduction furnace electrodes, air coolers, and circulating pumps that are interconnected via pipes; The pipe is used to fill the heat transfer medium, the circulating pump is used to drive the heat transfer medium to circulate in the pipe, and the air cooler is used to cool the heat transfer medium in the circulation. It also includes a heat transfer medium storage tank, which is interconnected with the polysilicon reduction furnace electrode, air cooler and circulating pump through the pipeline; The heat-conducting medium is deionized water.

2. The apparatus according to claim 1, characterized in that, The operating temperature of the heat-conducting medium is 45~65℃.

3. The apparatus according to claim 2, characterized in that, It also includes a heat transfer medium replenishment device connected to the heat transfer medium storage tank.

4. The apparatus according to claim 3, characterized in that, The circulating pump is a variable frequency pump.

5. The apparatus according to claim 4, characterized in that, The electrode heat-conducting medium inlet of the polycrystalline silicon reduction furnace is equipped with a first thermometer. The electrode cooling device for the polycrystalline silicon reduction furnace also includes a controller; The circulating pump and the first thermometer are electrically connected to the controller.

6. The apparatus according to claim 5, characterized in that, The electrode heat-conducting medium flow outlet of the polycrystalline silicon reduction furnace is equipped with a second thermometer. The second thermometer is electrically connected to the controller.

7. A polycrystalline silicon reduction furnace, characterized in that, The device includes the electrode cooling apparatus for the polycrystalline silicon reduction furnace as described in any one of claims 1-6.

8. A polycrystalline silicon production apparatus, characterized in that, Including the polycrystalline silicon reduction furnace as described in claim 7; or, The device includes the electrode cooling apparatus for the polycrystalline silicon reduction furnace as described in any one of claims 1-6.

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