Polysilicon reduction furnace electrode water pressure stabilizing system

Abstract

This application provides a pressure stabilizing system for electrode water in a polysilicon reduction furnace, relating to the field of polysilicon technology. It includes a sequentially connected main inlet pipe, branch inlet pipes, electrode heat exchange pipes, branch return pipes, and main return pipe. The main inlet pipe and main return pipe are connected to form a closed-loop path for circulating electrode water. A pressure stabilizing device is connected to the end of the main return pipe. The pressure stabilizing device includes a pressure stabilizing container with an inlet and an outlet, both of which are connected to the main return pipe. The pressure stabilizing device also includes a level control mechanism and a pressure control mechanism. The level control mechanism is used to stabilize the level of the liquid in the pressure stabilizing container; the pressure control mechanism is used to stabilize the pressure in the pressure stabilizing container. The combination of level and pressure closed-loop control, employing a dual-variable collaborative control method, ensures constant pressure in the main return pipe, thereby avoiding the problem of insufficient electrode water flow in the last few furnaces of a row of reduction furnaces.

Description

Technical Field

[0001] This utility model relates to the field of polycrystalline silicon technology, and in particular to a polycrystalline silicon reduction furnace electrode water pressure stabilization system. Background Technology

[0002] In polysilicon production plants, reduction furnace electrodes require circulating water cooling to prevent them from burning through due to high temperatures. The existing electrode water system uses electrode water pumps to deliver electrode water to multiple reduction furnaces in the reduction workshop. However, there is a problem of insufficient electrode water flow at the end of a row of reduction furnaces, which can easily lead to the reduction electrodes burning through due to water shortage and causing safety accidents.

[0003] One solution to the above problems is to increase the flow rate of the electrode water pump or add more pumps and increase the pump head to increase the flow rate and pressure of the electrode water in the terminal reduction furnace. However, this will increase the energy consumption and investment cost of the device and does not solve the inherent safety problem. Another solution is to add a flow switch alarm device to each electrode water pipe. Although this can alarm when the flow is insufficient, it also increases the investment and maintenance costs. Utility Model Content

[0004] In response to the above situation, this utility model provides a polycrystalline silicon reduction furnace electrode water pressure stabilization system, which aims to solve the technical problem that the existing electrode water system delivers electrode water to the reduction workshop for use by multiple reduction furnaces via an electrode water pump, but there is insufficient electrode water flow at the end of a row of reduction furnaces, which can easily lead to safety accidents caused by the reduction electrodes burning through due to water shortage.

[0005] To achieve the above objectives, this utility model provides the following technical solution:

[0006] This utility model provides a polycrystalline silicon reduction furnace electrode water pressure stabilization system, including a main water inlet pipe, a branch water inlet pipe, an electrode heat exchange pipe, a branch water return pipe and a main water return pipe connected in sequence. The main water inlet pipe and the main water return pipe are connected to form a closed loop path for the circulation of electrode water.

[0007] The end of the return water main is connected to a pressure stabilizing device, which includes a pressure stabilizing container. The pressure stabilizing container has an inlet and an outlet, and the outlet is connected to the return water main.

[0008] The pressure stabilizing device also includes a liquid level control mechanism and a pressure control mechanism; the liquid level control mechanism is used to control the liquid level stability in the pressure stabilizing container; the pressure control mechanism is used to control the pressure stability in the pressure stabilizing container.

[0009] In some embodiments of this utility model, the liquid level control mechanism includes:

[0010] A liquid level sensor is used to detect the liquid level in a pressure-stabilized container;

[0011] The pressure-stabilizing water supply valve is connected to the pressure-stabilizing container and is associated with the liquid level sensor.

[0012] In some embodiments of this utility model, the pressure control mechanism includes:

[0013] Pressure sensor used to detect pressure inside a pressure vessel;

[0014] The intake valve is connected to the pressure stabilizing container and is associated with the pressure sensor;

[0015] The vent valve is connected to the pressure vessel and is associated with a pressure sensor.

[0016] In some embodiments of this utility model, a cooling device is provided along the path of the return water main.

[0017] In some embodiments of this invention, the cooling device includes a dry air cooler.

[0018] In some embodiments of this invention, the cooling device includes a closed cooling tower.

[0019] In some embodiments of this utility model, a flow guide cone is provided inside the pressure stabilizing container, the flow guide cone is positioned close to the inlet, and the tip of the flow guide cone points towards the inlet.

[0020] In some embodiments of this utility model, a honeycomb damping plate is provided inside the pressure stabilizing container.

[0021] In some embodiments of this utility model, a microporous aeration device is provided inside the pressure stabilizing container.

[0022] In some embodiments of this invention, an electrode water replenishment device is connected to the closed-loop path.

[0023] The embodiments of this utility model have at least the following advantages or beneficial effects:

[0024] The system combines level and pressure closed-loop control with a dual-variable collaborative control approach to ensure constant pressure in the return water main, thus avoiding insufficient electrode water flow in the last few furnaces of a row of reduction furnaces. Furthermore, gas pressurization prevents water vaporization and improves pressure regulation response speed.

[0025] Other features and advantages of this invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. Attached Figure Description

[0026] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0027] Figure 1 This is a schematic diagram of the electrode water stabilization system of a polycrystalline silicon reduction furnace.

[0028] Icons: 1-Main water inlet pipe, 2-Branch water inlet pipe, 3-Reduction furnace, 4-Branch water return pipe, 5-Main water return pipe, 61-Dry air cooler, 62-Closed cooling tower, 7-Circulating pump, 81-Pressure stabilizing container, 82-Level sensor, 83-Pressure stabilizing water supply valve, 84-Pressure sensor, 85-Air inlet valve, 86-Vent valve, 9-Electrode water supply container. Detailed Implementation

[0029] In the following description, only certain exemplary embodiments are briefly described. As those skilled in the art will recognize, the described embodiments can be modified in various ways without departing from the spirit or scope of the present invention.

[0030] In this embodiment of the invention, unless otherwise explicitly specified and limited, the terms "connected" and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this embodiment of the invention according to the specific circumstances.

[0031] The embodiments of this utility model will be described in detail below.

[0032] Example 1

[0033] Firstly, this embodiment briefly introduces the existing reduction furnace 3, which includes electrodes, gaskets, and an electrical cabinet; it also includes electrode heat exchange pipes, gasket heat exchange pipes, and electrical cabinet heat exchange pipes. The electrode heat exchange pipes are used for heat exchange with the electrodes of the reduction furnace 3, the gasket heat exchange pipes are used for heat exchange with the gaskets of the reduction furnace 3, and the electrical cabinet heat exchange pipes are used for heat exchange with the electrical cabinet of the reduction furnace 3. The heat exchange medium flowing in the electrode heat exchange pipes, gasket heat exchange pipes, and electrical cabinet heat exchange pipes is electrode water.

[0034] Secondly, see Figure 1This embodiment provides an electrode water stabilization system for a polycrystalline silicon reduction furnace, including a main inlet pipe 1, branch inlet pipes 2, electrode heat exchange pipes, return branch pipes 4, and a main return pipe 5 connected in sequence. The main inlet pipe 1 and the main return pipe 5 are connected end-to-end to form a closed-loop path for the circulation of electrode water. The electrode heat exchange pipes are located at the reduction furnace 3, which has multiple... Figure 1 (4 are shown in the image).

[0035] A dry air cooler 61 and a closed cooling tower 62 are sequentially installed along the path of the return water main 5. The dry air cooler 61 and the closed cooling tower 62 are cooling devices used to cool down the electrode water after it has absorbed heat, so as to facilitate the recycling of the electrode water.

[0036] A circulation pump 7 is connected between the main water inlet pipe 1 and the closed cooling tower 62. The circulation pump 7 is a type of conveying device used to drive the flow of electrode water in the closed loop path.

[0037] A pressure stabilizing device is connected to the end of the return water main pipe 5 (where the pressure is lowest). The pressure stabilizing device is used to keep the pressure in the return water main pipe 5 constant. The pressure stabilizing device includes a pressure stabilizing container 81, a liquid level sensor 82, a pressure stabilizing water supply valve 83, a pressure sensor 84, an air inlet valve 85, and a vent valve 86.

[0038] The pressure stabilizing vessel 81 has an inlet at the top and an outlet at the bottom, with the outlet connected to the return water main pipe 5.

[0039] The liquid level sensor 82 is used to detect the liquid level in the pressure stabilizing container 81.

[0040] The pressure-stabilizing water supply valve 83 is connected to the pressure-stabilizing container 81 and is associated with the liquid level sensor 82.

[0041] Pressure sensor 84 is used to detect the pressure inside pressure vessel 81.

[0042] The intake valve 85 is connected to the pressure vessel 81 and associated with the pressure sensor 84.

[0043] Vent valve 86 is connected to pressure vessel 81 and associated with pressure sensor 84.

[0044] The liquid level sensor 82 and the pressure stabilizing water supply valve 83 form a liquid level control mechanism, which is used to control the liquid level stability in the pressure stabilizing container 81; the pressure sensor 84, the air inlet valve 85 and the vent valve 86 form a pressure control mechanism, which is used to control the pressure stability in the pressure stabilizing container 81.

[0045] The electrode water in the return water main 5 enters the pressure stabilizing container 81. Changes in the liquid level and pressure in the pressure stabilizing container 81 reflect pressure fluctuations in the return water main 5. This embodiment uses both liquid level control and pressure control to absorb return water pressure fluctuations, maintaining a dynamic balance in the pressure of the return water main 5, thereby ensuring a stable pressure difference between the inlet and outlet water in each branch. Specifically, the liquid level sensor 82 monitors the liquid level in the pressure stabilizing container 81 in real time. When the liquid level in the pressure stabilizing container 81 is lower than the set lower limit, the pressure stabilizing water supply valve 83 is opened; when it is higher than the set upper limit, the pressure stabilizing water supply valve 83 is closed. The pressure sensor 84 monitors the pressure in the pressure stabilizing container 81 in real time. When the pressure in the pressure stabilizing container 81 is lower than the set lower limit, the air inlet valve 85 is opened to introduce nitrogen or other gases for pressurization; when the pressure is higher than the set upper limit, the vent valve 86 is opened to release pressure.

[0046] Furthermore, a flow guide cone (not shown in the figure) is provided inside the pressure stabilizing vessel 81. The flow guide cone has a conical structure with its generatrix making a 45° angle with the central axis. The flow guide cone is positioned close to the inlet of the pressure stabilizing vessel 81, with its tip pointing towards the inlet of the pressure stabilizing vessel 81. That is, the tip of the flow guide cone points in the direction of incoming flow, while the bottom of the cone faces the inside of the tank. The flow guide cone can effectively eliminate inlet turbulence and vortex phenomena, significantly improve the water flow pattern, reduce energy loss, and improve the working efficiency of the pressure stabilizing tank.

[0047] Furthermore, a honeycomb damping plate (not shown in the figure) is installed on the bottom inner side of the pressure vessel 81 near the outlet. It consists of multiple closely arranged regular hexagonal cells, presenting a regular hexagonal honeycomb structure when viewed from the front. When water flows through the hexagonal honeycomb damping plate, the water flow is divided into multiple smaller streams entering each hexagonal cell, increasing the flow path and causing the water to continuously collide and rub within the cells, thereby consuming the energy of the water flow, stabilizing the flow, and reducing turbulence. Simultaneously, the hexagonal honeycomb structure exhibits good stability in all directions, enabling it to evenly withstand the pressure of the water flow.

[0048] Furthermore, a microporous aeration device (not shown in the figure) is installed inside the pressure stabilizing container 81 (30 cm from the top inner wall of the pressure stabilizing container 81). The microporous aeration device can use nitrogen as a gas source, and a dynamic air cushion layer is formed by nitrogen microbubbles inside the pressure stabilizing container 81 to effectively regulate the gas atmosphere inside the entire pressure stabilizing tank. Compared with the traditional airbag-type pressure stabilization, this has a higher linearity of pressure regulation and avoids the risk of airbag aging and failure.

[0049] An electrode water replenishment device, including an electrode water replenishment container 9, is connected between the closed-loop cooling tower 62 and the main inlet pipe 1. When electrode water is consumed in the closed-loop path, it can be replenished through the electrode water replenishment container 9. The electrode water replenishment container 9 only replenishes water and does not participate in the electrode water circulation. The level and pressure of the electrode water replenishment container 9 can be controlled and stabilized by referring to the control method of the liquid level and pressure in the pressure stabilizing container 81.

[0050] In summary, this embodiment has at least the following beneficial effects:

[0051] First, the liquid level and pressure closed-loop control are combined, and a dual-variable collaborative control method is adopted to ensure that the pressure of the return water main 5 is constant, thereby avoiding the problem of insufficient electrode water flow in the last few furnaces of a row of reduction furnaces 3.

[0052] Second, pressurizing with inert gases such as nitrogen can improve the pressure regulation response speed, reduce the amount of gas dissolved in the electrode water, and at the same time reduce the dissolved oxygen in the electrode water to prevent bacterial growth. This not only improves water quality but also helps prevent pipe corrosion.

[0053] Third, the investment in the pressure stabilizing device is relatively small, and it can achieve stable water flow at the three electrodes of each reduction furnace at a low cost, completely eliminating the risk of safety accidents caused by insufficient flow at the three electrodes of the remote reduction furnace burning through.

[0054] Fourth, it reduces the head requirement of the circulating pump 7, saving 15%~20% of energy; it also reduces equipment wear caused by pressure fluctuations and extends service life.

[0055] Example 2

[0056] See Figure 1 Unlike Embodiment 1, in this embodiment, either the dry air cooler 61 or the closed cooling tower 62 can be used. For example, in winter, only the dry air cooler 61 can meet the production needs, and the closed cooling tower 62 (which uses water spray combined with a fan for cooling) will not be turned on, so as to save water consumption and reduce energy consumption.

[0057] In this embodiment, either the liquid level control mechanism or the pressure control mechanism may be selected.

[0058] When the electrode water flows between the inlet branch pipe 2 and the return branch pipe 4, it also passes through the gasket heat exchange pipe and / or the electrical cabinet heat exchange pipe to meet the cooling requirements of the gasket and / or the electrical cabinet.

[0059] Finally, it should be noted that the above are merely preferred embodiments of this application and are not intended to limit this application. For those skilled in the art, this application can have various modifications and variations. Without conflict, the embodiments and features described in the embodiments of this application can be arbitrarily combined with each other. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A voltage stabilizing system for electrode water in a polycrystalline silicon reduction furnace, characterized in that, It includes a main inlet pipe, a branch inlet pipe, an electrode heat exchange pipe, a branch return pipe, and a main return pipe connected in sequence. The main inlet pipe and the main return pipe are connected to form a closed loop path for the circulation of electrode water. The end of the return water main is connected to a pressure stabilizing device, which includes a pressure stabilizing container. The pressure stabilizing container has an inlet and an outlet, and the outlet is connected to the return water main. The pressure stabilizing device further includes a liquid level control mechanism and a pressure control mechanism; the liquid level control mechanism is used to control the liquid level stability in the pressure stabilizing container; the pressure control mechanism is used to control the pressure stability in the pressure stabilizing container.

2. The electrode water stabilization system for a polycrystalline silicon reduction furnace according to claim 1, characterized in that, The liquid level control mechanism includes: A liquid level sensor is used to detect the liquid level inside the pressure stabilizing container; A pressure-stabilizing water supply valve is connected to the pressure-stabilizing container and associated with the liquid level sensor.

3. The electrode water stabilization system for a polycrystalline silicon reduction furnace according to claim 1, characterized in that, The pressure control mechanism includes: A pressure sensor is used to detect the pressure inside the pressure stabilizing container; An intake valve is connected to the pressure stabilizing container and associated with the pressure sensor; A vent valve is connected to the pressure stabilizing vessel and associated with the pressure sensor.

4. The electrode water stabilization system for a polycrystalline silicon reduction furnace according to claim 1, characterized in that, A cooling device is installed along the path of the return water main.

5. The electrode water stabilization system for a polycrystalline silicon reduction furnace according to claim 4, characterized in that, The cooling device includes a dry air cooler.

6. The electrode water stabilization system for a polycrystalline silicon reduction furnace according to claim 4, characterized in that, The cooling device includes a closed cooling tower.

7. The electrode water stabilization system for a polycrystalline silicon reduction furnace according to claim 1, characterized in that, The pressure stabilizing container is equipped with a flow guide cone, which is positioned close to the inlet, with the tip of the flow guide cone pointing towards the inlet.

8. The electrode water stabilization system for a polycrystalline silicon reduction furnace according to claim 1, characterized in that, The pressure stabilizing container is equipped with a honeycomb damping plate.

9. The electrode water stabilization system for a polycrystalline silicon reduction furnace according to claim 1, characterized in that, The pressure stabilizing container is equipped with a microporous aeration device.

10. The electrode water stabilization system for a polycrystalline silicon reduction furnace according to claim 1, characterized in that, The closed-loop path is connected to an electrode water replenishment device.

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