Silicon water refining system

Abstract

The utility model relates to a silicon water refining system, and relates to the field of silicon smelting, the silicon water refining system comprises a ladle used for containing silicon water and a temperature sensor used for monitoring the internal temperature of the silicon water in the ladle, and the temperature sensor is located in an inner cavity of the ladle and can be covered by the silicon water in the ladle; the device further comprises a controller, a weighing device and an electric valve. The controller is used for receiving a temperature signal monitored by the temperature sensor and a mass signal monitored by the weighing device and sending a corresponding control signal to the electric valve. The temperature sensor is used for measuring the temperature in the silicon water, the effect of improving silicon water refining is achieved, and the product quality is improved.

Description

Technical Field

[0001] The present application relates to the field of silicon smelting, and in particular to a silicon water refining system. Background Art

[0002] Industrial silicon is made of silicon ore containing silicon dioxide and carbonaceous reducing agent, and is smelted in a submerged arc furnace. It contains more than 98% silicon. Industrial silicon is the most basic functional material for information technology, photovoltaic power generation, and new materials industries, and is an upstream product in the silicon product industry chain.

[0003] The most commonly used impurity removal method in industrial silicon plants is to refine the industrial silicon in a ladle outside the furnace. That is, a mixture of oxygen and air is introduced into the ladle at the same time as it comes out of the furnace to separate the impurities in the high-temperature silicon water from the silicon water, remove aluminum and calcium in the silicon, and achieve the effect of refining the silicon water. The highest temperature of the silicon water can reach 2500℃.

[0004] In the prior art, the completion node of oxygen blowing refining is obtained by manual observation, that is, during the process of oxygen blowing refining of high-temperature silicon water in the ladle, experienced staff observe the sparks splashed by the silicon water or the calcium spots floating on the surface of the high-temperature silicon water to determine whether the oxygen blowing refining is completed. After the silicon water refining is completed, the oxygen blowing is stopped and the silicon water is unpacked.

[0005] The completion of oxygen blowing refining is determined by manually observing the surface of silicon water. The refining process depends entirely on the experience of personnel to judge the degree of oxidation. The impurity removal rate is low, the impurities in the product are uneven, and the silicon blocks completed in the ingot mold require a lot of manual screening. Utility Model Content

[0006] The present application provides a silicon water refining system, which accurately monitors the temperature of silicon water in a package and improves the refining accuracy of silicon water.

[0007] The present application provides a silicon water refining system, which includes a bag for containing silicon water and a temperature sensor for monitoring the internal temperature of the silicon water in the bag.

[0008] Optionally, the temperature sensor is located in the inner cavity of the platform package and can be covered by the silicon water in the platform package.

[0009] Optionally, the temperature sensor is arranged on the inner wall of the platform package.

[0010] Optionally, a through hole is provided on the side wall of the platform package, and a probe of the temperature sensor passes through the through hole and extends into the inner cavity of the platform package.

[0011] Optionally, multiple temperature sensors are provided.

[0012] Optionally, a plurality of temperature sensors are arranged in the platform package at intervals along a first direction, and the first direction is a direction from the bottom wall of the platform package toward the opening of the platform package.

[0013] Optionally, a plurality of temperature sensors are arranged in the platform package at intervals along the circumference of the side wall of the platform package.

[0014] Optionally, it also includes an air supply device, which includes an air supply pipe, one end of which is passed through the bottom wall of the platform package, and the air supply pipe is located in the middle area of ​​the bottom wall of the platform package.

[0015] Optionally, it also includes a controller and an electric valve; wherein the controller is used to receive the temperature signal monitored by the temperature sensor and send a corresponding control signal to the electric valve; the electric valve is connected to the air supply pipe, and the electric valve adjusts its opening when receiving the control signal sent by the controller, so as to control the flow in the air supply pipe.

[0016] Optionally, a weighing device is also included, which is placed under the platform bag to monitor the weight of the silicone water in the platform bag; the controller is used to receive the temperature signal monitored by the temperature sensor and the quality signal monitored by the weighing device and send a corresponding control signal to the electric valve.

[0017] In the above technical scheme, the accurate internal temperature of the silicon water is obtained by the temperature sensor, and the internal temperature of the silicon water with a large contact area with the gas and intense reaction can be obtained in time. According to the corresponding internal temperature of the silicon water, the flow rate of the gas is controlled, so that the reaction control of the gas and silicon water is more accurate, thereby improving the refining effect of the silicon water.

[0018] By weighing the entire package, the impurity removal status of the silicone water can be calculated, which helps to reduce the influence of human factors, accurately obtain products with better refining effects, and ensure product quality.

[0019] By obtaining the accurate parameters of the ladle quality and the temperature inside the silicon water in real time, the opening of the electric valve is adjusted to control the gas flow into the silicon water, thereby improving the impurity removal rate during the refining process. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 The figure is a schematic diagram of the cross-sectional structure of a platform package in an embodiment.

[0021] 1. Platform package; 2. Temperature sensor; 3. Air supply pipe; 4. Electric valve; 5. Weighing equipment; 6. Liquid level. DETAILED DESCRIPTION

[0022] The present application is further described in detail below through the accompanying drawings and embodiments. Through these descriptions, the characteristics and advantages of the present application will become clearer and more specific.

[0023] The word "exemplary" is used exclusively herein to mean "serving as an example, embodiment, or illustration." Any embodiment described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments. Although various aspects of the embodiments are shown in the drawings, the drawings are not necessarily drawn to scale unless otherwise noted.

[0024] In addition, the technical features involved in different embodiments of the present application described below can be combined with each other as long as they do not conflict with each other.

[0025] The embodiment of the present application discloses a silicon water refining system. When refining silicon water, silicon water is poured from a mineral-arc furnace into a ladle, and gas is introduced into the silicon water. During ventilation, air is introduced first and then oxygen, and the flow rates of air and oxygen are adjusted to a suitable ratio; the gas reacts with impurities in the silicon water, so that the impurities in the silicon water are separated from the silicon water, and the impurities in the silicon water float up to form slag.

[0026] Reference Figure 1 The silicon water refining system includes a bag 1 for containing silicon water and a temperature sensor 2 for monitoring the internal temperature of the silicon water in the bag 1.

[0027] Specifically, for the temperature sensor 2 that monitors the internal temperature of the silicon water in the platform package 1, on the one hand, a sensor that can be placed outside the silicon water and can detect the temperature inside the silicon water can be used; on the other hand, the probe of the temperature sensor 2 can be placed in the silicon water, and the temperature detected by the temperature sensor 2 is the temperature inside the silicon water.

[0028] In this embodiment, an example is taken in which the probe of the temperature sensor 2 is placed into the silicon water of the platform package 1 and the silicon water submerges the probe of the temperature sensor 2 .

[0029] In another embodiment, a form of temperature sensor that can be placed outside the silicon water and can detect the inside of the silicon water includes: the temperature sensor detects the temperature of the surface of the silicon water, and the temperature of the surface of the silicon water detected by the temperature sensor is used as the independent variable. The temperature inside the silicon water is calculated as the dependent variable based on the properties of the silicon water, the ventilation volume in the silicon water, the size of the platform bag and other parameters.

[0030] In the metallurgical process of the prior art, such as the steelmaking process, when monitoring the temperature of molten steel in a ladle, a high temperature resistant temperature sensor is used to monitor the temperature of the molten steel. The temperature sensor is located above the ladle and measures the temperature of the molten steel surface.

[0031] In the field of silicon water refining, the temperature of silicon water is measured by measuring the surface temperature of silicon water through a temperature sensor arranged outside the platform package. Those skilled in the art assume that the surface temperature of silicon water is the temperature of silicon water.

[0032] Compared with measuring the temperature of the silicon water surface, controlling the flow rate of the gas fed into the silicon water will result in insufficient refining of the silicon water and low stability of the impurity content of the refined silicon water. This is partly due to the fact that the silicon water surface is the last stage where the gas fed into the silicon water leaves the silicon water during the floating process. The surface of the silicon water has a smaller area in contact with the gas than the internal part of the silicon water, and the reaction rate is lower.

[0033] In the present application, by using the temperature sensor 2 to measure the internal temperature of the silicon water, the accurate internal temperature of the silicon water is obtained, which helps to adjust and control the flow rate of the gas in time, making the reaction control of the gas and silicon water more accurate, thereby improving the refining effect of the silicon water and obtaining a product with stable quality and low impurity content.

[0034] For the convenience of description, a first direction is defined, which is the direction from the bottom wall of the platform package 1 to the opening of the platform package 1, and is also a direction perpendicular to the bottom wall of the platform package 1. The first direction is indicated as X direction in the drawings.

[0035] Reference Figure 1 As an optional solution, the silicon water refining system also includes an air supply device, which includes an air supply pipe 3, one end of which is passed through the bottom wall of the platform package 1, and the air supply pipe 3 is located in the middle area of ​​the bottom wall of the platform package 1.

[0036] Specifically, the gas supply device is a device for supplying gas into the silicon water in the platform bag 1. The gas supply device includes a gas supply pipe 3, which is a pipe that can supply gas into the silicon water in the platform bag 1. In this embodiment, the gas supply pipe 3 includes a main pipe and two branch pipes, one end of the main pipe is located in the inner cavity of the platform bag 1, and the other end of the main pipe is connected to the two branch pipes located outside the platform bag 1.

[0037] The gas supply equipment also includes an air source and an oxygen source. The two branch pipes are respectively used for one-to-one communication with the air source and the oxygen source. The air source and the oxygen source provide gas with stable pressure.

[0038] In another embodiment, the gas supply pipe 3 includes three or four branch pipes, and the branch pipes are connected to gas sources of other types of gases.

[0039] In another embodiment, the air supply pipe 3 may merely represent a main pipe located in the inner cavity of the platform package 1 .

[0040] In another embodiment, at least two air supply pipes 3 are provided, one end of which is connected to the air source, and the other end extends into the inner cavity of the platform bag 1 into the silicon water. One end of which is connected to the oxygen source, and the other end extends into the inner cavity of the platform bag 1 into the silicon water.

[0041] The air supply pipe 3 is located in the middle area of ​​the bottom wall of the platform bag 1. For example, a first hole is provided on the bottom wall of the platform bag 1. The first hole is provided along a first direction, passes through the bottom wall of the platform bag 1 and is located in the middle area of ​​the bottom wall. One end of the air supply pipe 3 that supplies air to the inner cavity of the platform bag 1 passes through the first hole and extends into the inner cavity of the platform bag 1.

[0042] One end of the air supply pipe 3 located in the inner cavity of the platform package 1 is arranged along the first direction, and the center line of the part of the air supply pipe 3 located in the inner cavity of the platform package 1 is coaxial with the center line of the platform package 1 .

[0043] The air supply pipe 3 is located in the middle area of ​​the bottom wall of the platform bag 1. When there is silicon water in the platform bag 1, the air supply pipe 3 is located in the middle of the silicon water. Compared with other positions, the gas entering the silicon water from the air supply pipe 3 is in more complete contact with the silicon water, and the impurity removal efficiency is higher.

[0044] Reference Figure 1 As an optional solution, the silicon water refining system also includes a controller and an electric valve 4 , and the controller is used to receive the temperature signal monitored by the temperature sensor 2 and send a corresponding control signal to the electric valve 4 .

[0045] The electric valve 4 is connected to the air supply pipe 3 , and the electric valve 4 adjusts its opening when receiving a control signal sent by the controller, so as to control the flow rate in the air supply pipe 3 .

[0046] Specifically, the electric valve 4 can be adjusted to a corresponding opening according to the received control signal and remain unchanged, so as to control the flow rate of the gas sent from the air delivery pipe 3 into the silicon water. Two electric valves 4 are provided, and the two electric valves 4 are connected to the two branch pipes one by one, respectively, and the electric valves 4 control the flow rate of the corresponding branch pipes. The temperature sensor 2 can detect the temperature inside the silicon water in real time and send a signal to the controller.

[0047] The controller receives the temperature signal monitored by the temperature sensor 2 and sends corresponding control signals to the two electric valves 4 respectively.

[0048] The controller and the electric valve 4 cooperate to adjust the flow rate of air and oxygen delivered by the air supply pipe 3 into the silicon water, which can improve the accuracy of air supply control and help improve the refining effect of the silicon water.

[0049] Reference Figure 1 As an optional solution, the silicon water refining system further includes a weighing device 5 , which is placed under the platform bag 1 to monitor the weight of the silicon water in the platform bag 1 .

[0050] The controller is used to receive the temperature signal monitored by the temperature sensor 2 and the mass signal monitored by the weighing device 5 and send a corresponding control signal to the electric valve 4 .

[0051] Specifically, the bag 1 is placed above the weighing device 5 , and the weighing device 5 measures the mass change of the silicon water in the bag 1 in real time. The controller determines the refining degree according to the weight change in the bag 1 .

[0052] The process of silicon water refining system is described as follows:

[0053] Record the tare weight of bag 1 before adding silicone water.

[0054] After receiving the silicone water, record the total weight of the platform package 1 and the silicone water, and preliminarily determine the oxygen blowing flow rate and ratio through the controller.

[0055] During the oxygen blowing refining process, the ladle 1 is continuously weighed; during the process, the controller continuously performs comprehensive calculations based on the changes in temperature and weight to determine the refining effect. The opening of the oxygen electric valve 4 is controlled after comprehensive calculations by the weighing device 5 and the temperature, thereby realizing automatic refining of silicon water.

[0056] It is determined whether oxygen blowing can be ended based on the data of the temperature measuring element. When the temperature inside the silicon water reaches the set requirement, the electric valve 4 is closed to stop ventilation into the silicon water, thus completing the silicon water refining.

[0057] Reference Figure 1 As an optional solution, the temperature sensor 2 is located in the inner cavity of the platform package 1 and can be covered by the silicon water in the platform package 1.

[0058] Specifically, the temperature sensor 2 can be covered by the silicon water in the platform package 1, which means that at least part of the probe of the temperature sensor 2 is covered by the silicon water in the platform package 1, and the probe can be partially located in the silicon water or completely located in the silicon water. It can also be understood that the part of the temperature sensor 2 that can withstand high temperature is located inside the silicon water. The liquid level 6 of the silicon water is shown in the figure.

[0059] The part of the temperature sensor 2 that cannot withstand high temperatures is separated from the probe part extending into the silicone water by a fireproof component, and the fireproof component includes but is not limited to fireproof cotton or fireproof felt.

[0060] Since the probe of temperature sensor 2 is placed in silicon water, the temperature of silicon water is about 1600°C. Those skilled in the art generally have no motivation to place the probe of temperature sensor 2 in silicon water because the temperature of silicon water has high requirements on temperature sensor 2 and the probe of temperature sensor 2 is easily damaged when in direct contact with silicon water. In order to accurately measure the temperature inside silicon water and obtain highly refined silicon water, the present application adopts the method of directly extending the probe of temperature sensor 2 into silicon water to measure the temperature inside silicon water.

[0061] The probe of the temperature sensor 2 is put into the silicon water and covered by the silicon water in the platform package 1. The temperature actually measured by the probe is the temperature inside the silicon water. The temperature measurement is accurate. The more accurate the temperature measurement inside the silicon water is, the more accurately the gas flow rate sent into the silicon water can be controlled, thereby improving the refining degree of the silicon water.

[0062] Reference Figure 1 As an optional solution, the temperature sensor 2 is arranged on the inner wall of the platform package 1.

[0063] Specifically, the temperature sensor 2 is fixed on the inner wall of the platform package 1 , and the probe of the temperature sensor 2 extends into the silicon water in the platform package 1 .

[0064] The gas entering the platform package 1 through the air supply pipe 3 comes into contact with the silicon water, which will affect the temperature of the silicon water. The air supply pipe 3 is located in the middle area of ​​the bottom wall of the platform package 1. The probe of the temperature sensor 2 is placed close to the inner wall of the platform package 1, so that the air supply pipe 3 is relatively far away from the temperature sensor 2. The gas supplied into the silicon water has less effect on the temperature measured by the temperature sensor 2, and the temperature inside the silicon water measured by the temperature sensor 2 is more accurate.

[0065] Reference Figure 1 As an optional solution, a through hole is provided on the side wall of the platform package 1, and the probe of the temperature sensor 2 extends into the inner cavity of the platform package 1 through the through hole.

[0066] Specifically, a method for forming the through hole on the platform bag 1 is that the platform bag 1 is formed by stacking refractory bricks. When the refractory bricks are stacked, gaps are reserved at corresponding positions of the through holes. After the platform bag 1 is stacked, the through hole structure is formed.

[0067] Another way of forming the through hole on the platform bag 1 is to open a hole on the platform bag 1 that passes through the side wall of the platform bag 1. The through hole is along the radial direction of the platform bag 1. The hole of the platform bag 1 connects the inner cavity of the platform bag 1 and the external space of the platform bag 1.

[0068] Compared to inserting the probe of the temperature sensor 2 from the opening of the platform package 1 toward the bottom wall of the platform package 1 into the silicone water, or the probe of the temperature sensor 2 passes through the bottom wall of the platform package 1 and extends into the inner cavity of the platform package 1 and is inserted into the silicone water.

[0069] The temperature sensor 2 in this embodiment can only extend the probe of the temperature sensor 2 into the silicon water, and the other parts of the temperature sensor 2 are located in the through hole and outside the platform package 1 to avoid contact with the silicon water, which can reduce the damage of the silicon water to other parts of the temperature sensor 2 other than the probe. The other parts of the temperature sensor 2 do not contact with the silicon water, which can reduce the impact on the silicon water refining and improve the silicon water refining effect.

[0070] Reference Figure 1As an optional solution, multiple temperature sensors 2 are provided. In this embodiment, at least two temperature sensors 2 are provided. For example, eight thermometers are installed inside the stage bag 1. The temperature sensor 2 observes the temperature in real time and determines the degree of refining according to the different reaction temperatures of different impurities and oxygen in the stage bag 1 solution.

[0071] By acquiring temperature data measured by multiple temperature sensors 2, on the one hand, multiple temperature sensors 2 can be verified with each other, and on the other hand, more accurate silicon water temperature can be obtained by calculation based on the measurement results of multiple temperature sensors 2, thereby reducing the measurement error of a single temperature sensor 2.

[0072] In another embodiment, only one temperature sensor 2 may be provided.

[0073] Reference Figure 1 As an optional solution, a plurality of temperature sensors 2 are arranged in the platform package 1 at intervals along the first direction.

[0074] Specifically, the plurality of temperature sensors 2 are divided into at least two groups, each group of temperature sensors 2 includes a plurality of temperature sensors 2, each group of temperature sensors 2 is located at the same height of the platform package 1, and the temperature sensors 2 of different groups are arranged at intervals along the first direction. Exemplarily, the plurality of temperature sensors 2 include two groups of temperature sensors 2, and the two groups of temperature sensors 2 are arranged at intervals along the first direction.

[0075] The first direction is the direction from the bottom wall of the platform package 1 toward the opening of the platform package 1. The first direction is also the height direction from bottom to top when the platform package 1 is placed. The gas enters the silicon water from near the bottom wall of the platform package 1. During the floating process of the gas, the silicon water is stirred and reacts with impurities in the silicon water to reduce the impurities in the silicon water.

[0076] The different heights of the silicon water in the ladle 1 will cause certain changes in the temperature of the silicon water at different heights; by arranging multiple temperature sensors 2 at intervals along the first direction, the temperatures of the silicon water at multiple different heights can be obtained, thereby improving the accuracy of the detected silicon water temperature and helping to improve the refining effect.

[0077] Reference Figure 1 As an optional solution, a plurality of temperature sensors 2 are arranged in the platform package 1 at intervals along the circumferential direction of the side wall of the platform package 1 .

[0078] Specifically, each group of temperature sensors 2 includes four temperature sensors 2 , each group of temperature sensors 2 is located at the same height of the platform package 1 , and the four temperature sensors 2 of each group of temperature sensors 2 are evenly distributed along the circumferential direction on the side wall of the platform package 1 .

[0079] Multiple temperature sensors 2 in the same group can be mutually verified. According to the silicon water temperatures in different areas at the same height of the platform package 1 measured by the multiple temperature sensors 2, the silicon water temperature at the same height obtained is more accurate.

[0080] The "parallel" and "perpendicular" mentioned in this application can not only be completely parallel or perpendicular, but also can have a certain error; for example, if the angle between the two is greater than or equal to 0° and less than or equal to 5°, the two are considered to be parallel to each other; if the angle between the two is greater than or equal to 85° and less than or equal to 95°, the two are considered to be perpendicular to each other.

[0081] In the description of the present application, it should be noted that the terms "upper", "lower", "inside", "outside", "front", "back", "left", "right", etc. indicate directions or positional relationships based on the directions or positional relationships in the working state of the present application. They are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, they should not be understood as limitations on the present application.

[0082] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "install", "connect" and "connect" should be understood in a broad sense. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0083] The present application has been described above in conjunction with preferred embodiments, but these embodiments are only exemplary and serve only as an illustration. On this basis, various replacements and improvements may be made to the present application, all of which fall within the scope of protection of the present application.

Claims

1. A silicon water refining system, characterized in that: It comprises a platform bag for containing silicon water and a temperature sensor for monitoring the internal temperature of the silicon water in the platform bag; the temperature sensor is located in the inner cavity of the platform bag and can be covered by the silicon water in the platform bag.

2. The silicon water refining system according to claim 1, characterized in that: The temperature sensor is arranged on the inner wall of the platform package.

3. The silicon water refining system according to claim 2, characterized in that: The side wall of the platform package is provided with a through hole, and the probe of the temperature sensor passes through the through hole and extends into the inner cavity of the platform package.

4. The silicon water refining system according to any one of claims 1 to 3, characterized in that: A plurality of temperature sensors are provided.

5. The silicon water refining system according to claim 4, characterized in that: The plurality of temperature sensors are arranged in the stage package at intervals along a first direction, and the first direction is a direction from the bottom wall of the stage package toward the opening of the stage package.

6. The silicon water refining system according to claim 4, characterized in that: A plurality of the temperature sensors are arranged in the platform package at intervals along the circumferential direction of the side wall of the platform package.

7. The silicon water refining system according to claim 1, characterized in that: It also includes an air supply device, which includes an air supply pipe. One end of the air supply pipe is penetrated through the bottom wall of the platform package, and the air supply pipe is located in the middle area of ​​the bottom wall of the platform package.

8. The silicon water refining system according to claim 7, characterized in that: It also includes a controller and an electric valve; wherein, The controller is used to receive the temperature signal monitored by the temperature sensor and send a corresponding control signal to the electric valve; The electric valve is connected to the air supply pipe. When receiving a control signal sent by the controller, the electric valve adjusts its opening to control the flow rate in the air supply pipe.

9. The silicon water refining system according to claim 8, characterized in that: Also included is a weighing device, which is used to be placed under the platform bag and is used to monitor the weight of the silicon water in the platform bag; The controller is used to receive the temperature signal monitored by the temperature sensor and the mass signal monitored by the weighing device and send a corresponding control signal to the electric valve.

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