Method and system for determining dissolution rate of aluminum oxide in molten electrolyte

Abstract

A method and system for determining the dissolution rate of aluminum oxide in a molten electrolyte (52). The determination method comprises: step 110, placing a crucible (50) containing a reference substance (51) and a solid electrolyte into a heating furnace (10); step 120, controlling the heating furnace (10) to heat the crucible (50); step 130, collecting a first image of the reference substance (51) in the crucible (50) when the solid electrolyte becomes a molten electrolyte (52); step 140, adding aluminum oxide to be determined into the crucible (50); step 150, after the aluminum oxide to be determined is added into the crucible (50), collecting a second image of the reference substance (51) in the crucible (50) in real time; and step 160, on the basis of the first image and the second image, determining the dissolution rate of the aluminum oxide to be determined in the molten electrolyte (52).

Description

Method and system for measuring dissolution rate of alumina in molten electrolyte

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to Chinese patent application No. 2024103301697 filed on March 22, 2024, the entire contents of which are incorporated herein by reference. Technical Field

[0003] The present disclosure relates to the technical field of alumina and electrolytic aluminum production, and in particular to a method and system for measuring the dissolution rate of alumina in a molten electrolyte. Background Art

[0004] Accurately measuring the dissolution rate of aluminum oxide in molten electrolyte is crucial for improving aluminum electrolytic production operations and optimizing technical indicators. Currently, due to difficulties and insufficient research, there is no unified test and evaluation method for measuring the dissolution rate of aluminum oxide in molten electrolytes. The main technical approaches explored include visual observation, sampling chemical analysis, and electrochemical measurement. Among these methods, visual observation is relatively intuitive, but due to the limitations of human physiology, it is not suitable for continuous measurement of large numbers of samples and has a low degree of automation. While sampling chemical analysis offers relatively accurate results, the analysis process is complex and the test results are delayed, failing to meet production control requirements. Electrochemical measurement offers greater real-time performance, and linear voltammetry, a common electrochemical measurement method, boasts high accuracy and is widely used internationally. However, this method requires the specialized design and fabrication of electrodes with specialized structures, and the high technical requirements for electrode fabrication limit its widespread application. Therefore, reducing the complexity of measuring the dissolution rate of aluminum oxide in molten electrolytes is an urgent technical challenge.

[0005] Summary of the Invention

[0006] According to the embodiments disclosed in the present application, a method and system for measuring the dissolution rate of aluminum oxide in a molten electrolyte are provided. The technical solution provided based on the embodiments of the present disclosure can reduce the complexity of measuring the dissolution rate of aluminum oxide in a molten electrolyte.

[0007] Other features and advantages of the present disclosure will be apparent from the following detailed description, or may be learned in part from the practice of the present disclosure.

[0008] According to a first aspect of the present disclosure, a method for determining the dissolution rate of aluminum oxide in a molten electrolyte is provided, the method comprising: placing a crucible containing a reference object and a solid electrolyte in a heating furnace; controlling the heating furnace to heat the crucible; when the solid electrolyte becomes a molten electrolyte, collecting a first image of the reference object in the crucible; adding the aluminum oxide to be measured into the crucible; after adding the aluminum oxide to be measured into the crucible, collecting a second image of the reference object in the crucible in real time; and determining the dissolution rate of the aluminum oxide to be measured in the molten electrolyte based on the first image and the second image.

[0009]

[0010] According to a second aspect of the present disclosure, a system for measuring the dissolution rate of aluminum oxide in a molten electrolyte is provided, the system comprising: a heating furnace for heating a crucible placed in the heating furnace, the crucible containing a reference object and a solid electrolyte; a feeding unit for adding the aluminum oxide to be measured into the crucible after the solid electrolyte becomes a molten electrolyte; an image acquisition unit for capturing a first image of the reference object in the crucible when the solid electrolyte becomes a molten electrolyte, and also for capturing a second image of the reference object in the crucible in real time after the aluminum oxide to be measured is added into the crucible; and an analysis unit connected to the image acquisition unit for determining the dissolution rate of the aluminum oxide to be measured in the molten electrolyte based on the first image and the second image.

[0011] BRIEF DESCRIPTION OF THE DRAWINGS

[0012] The accompanying drawings are incorporated into and constitute a part of the specification, illustrate embodiments consistent with the present disclosure, and together with the specification, are used to explain the principles of the present disclosure. Obviously, the drawings described below are only some embodiments of the present disclosure, and those skilled in the art can derive other drawings based on these drawings without inventive effort. In the drawings:

[0013] FIG1 shows a schematic flow chart of a method for determining the dissolution rate of aluminum oxide in a molten electrolyte according to some embodiments of the present disclosure;

[0014] FIG2 is a schematic diagram showing a detailed process of determining the dissolution rate of the aluminum oxide to be tested in the molten electrolyte based on the first image and the second image according to some embodiments of the present disclosure;

[0015] FIG3 shows a schematic structural diagram of a system for measuring the dissolution rate of aluminum oxide in a molten electrolyte according to some embodiments of the present disclosure;

[0016] FIG4 shows a detailed schematic diagram of a system for measuring the dissolution rate of aluminum oxide in a molten electrolyte according to some embodiments of the present disclosure; and

[0017] FIG5 shows a detailed schematic diagram of a reference object and a molten electrolyte contained in a crucible according to some embodiments of the present disclosure.

[0018] Figure numerals: 10, heating furnace; 11, heating chamber; 12, temperature acquisition unit; 13, control unit; 14, top opening; 20, image acquisition unit; 21, camera device; 22, adjustment bracket; 23, light source supply device; 30, analysis unit; 40, feeding unit; 50, crucible; 51, reference object; 52, molten electrolyte. DETAILED DESCRIPTION

[0019] Typical embodiments that embody the features and advantages of the present disclosure will be described in detail in the following description. It should be understood that the present disclosure can have various variations in different embodiments without departing from the scope of the present disclosure, and the descriptions and illustrations therein are essentially for illustrative purposes and not for limiting the present disclosure.

[0020] In the description of the present disclosure, it should be noted that the terms "vertical", "up", "down", "horizontal", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present disclosure and simplifying the description, and do not indicate or imply that the system or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present disclosure.

[0021] It should also be noted that, in the description of this disclosure, unless otherwise expressly specified or limited, the terms "disposed," "installed," "connected," and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections or electrical connections; they can refer to direct connections or indirect connections through an intermediate medium; and they can refer to internal connections between two components. Those skilled in the art will understand the specific meanings of the above terms in this disclosure based on specific circumstances.

[0022] The following will describe some embodiments of the present disclosure in detail with reference to the accompanying drawings. In the absence of conflict, the following embodiments and features therein may be combined with each other.

[0023] According to a first aspect of the present disclosure, a method for determining the dissolution rate of aluminum oxide in a molten electrolyte is provided.

[0024] 1 , which shows a flow chart of a method for determining the dissolution rate of aluminum oxide in a molten electrolyte according to some embodiments of the present disclosure. The method for determining the dissolution rate of aluminum oxide in a molten electrolyte may include the following steps 110 to 160 .

[0025] In step 110 , a crucible containing a reference material and a solid electrolyte is placed in a heating furnace.

[0026] It should be noted that the selected reference material does not react with the molten electrolyte and does not undergo physical or chemical changes during the measurement of the dissolution rate of aluminum oxide in the molten electrolyte.

[0027] In some embodiments, the shape of the selected reference object is not limited, and can be a sheet shape, a straight line shape, a ring shape, a mesh shape, etc.

[0028] In some embodiments, the reference material is selected to be platinum or nickel.

[0029] In some embodiments, the crucible material may be selected from platinum, silicon carbide, and quartz.

[0030] In some embodiments, the type of solid electrolyte can be selected based on the aluminum electrolysis process. In some embodiments, a mixture of cryolite and aluminum fluoride can be selected; a factory electrolyte with an initial aluminum oxide content of 2.5% can also be selected; a mixture of potassium fluoride, sodium fluoride, aluminum fluoride, and aluminum oxide can also be selected; and so on. This disclosure does not limit the material type of the solid electrolyte.

[0031] In some embodiments, the melting temperature of the selected solid electrolyte may be 750-1000°C.

[0032] In some embodiments, the positions of the reference object and the solid electrolyte contained in the crucible can be such that the reference object is placed at the bottom of the crucible and the solid electrolyte is placed on the reference object.

[0033] Continuing to refer to FIG. 1 , in step 120 , the heating furnace is controlled to heat the crucible.

[0034] It should be noted that the purpose of controlling the heating furnace to heat the crucible is to convert the solid electrolyte in the crucible into a molten electrolyte, so as to prepare for the subsequent measurement of the dissolution rate of aluminum oxide in the molten electrolyte.

[0035] Step 120 may further include the following steps 121 to 122:

[0036] Step 121, controlling the heating furnace to heat the crucible according to a heating mode, and collecting the temperature in the heating furnace in real time; and

[0037] Step 122: If the temperature in the heating furnace reaches the target temperature, control the heating furnace to switch from the heating mode to the heat preservation mode.

[0038] In some embodiments, heating parameters can be pre-set for the heating furnace's heating mode. In some embodiments, a heating rate of 10 to 18°C / min can be set within a temperature range of 20 to 1000°C. Furthermore, while the heating furnace is heating the crucible according to the heating mode, the power of the heating element in the heating furnace can be adjusted according to the pre-set heating parameters to achieve heating of the crucible according to the predetermined heating mode.

[0039] In some embodiments, the heat preservation mode of the heating furnace may be configured with heat preservation parameters. In some embodiments, the temperature in the heating furnace may be controlled to be within a preset temperature range, which may be ±0.5° C. of the target temperature.

[0040] In some embodiments, a temperature acquisition unit may be provided in the heating furnace, and the temperature in the heating furnace may be acquired in real time by the temperature acquisition unit to determine whether the temperature in the heating furnace has reached the target temperature.

[0041] In some embodiments, the target temperature may be set to be greater than or equal to the melting temperature of the selected solid electrolyte. In some embodiments, the target temperature may be 750-1000°C.

[0042] In summary, based on the control of the heating furnace, the solid electrolyte in the crucible can be melted in the heating furnace to form a molten electrolyte.

[0043] Continuing to refer to FIG. 1 , in step 130 , when the solid electrolyte becomes a molten electrolyte, a first image of the reference object in the crucible is captured.

[0044] It should be noted that the first image of the reference object is collected when the solid electrolyte in the crucible is completely melted, that is, becomes a molten electrolyte, and the aluminum oxide to be tested has not yet been added to the crucible.

[0045] In some embodiments, the crucible may be imaged at a position directly above the crucible to obtain the first image.

[0046] It can be understood that, since the solid electrolyte in the crucible has been completely melted, the reference object reflected in the captured first image is in an unobstructed state.

[0047] Continuing with FIG. 1 , in step 140 , aluminum oxide to be tested is added into the crucible.

[0048] In some embodiments, when the aluminum oxide to be tested is added into the crucible, the time when the aluminum oxide to be tested is added into the crucible needs to be recorded as the first time.

[0049] In some embodiments, a certain mass of aluminum oxide to be tested may be weighed in advance.

[0050] It should be noted that in order to improve the accuracy of the subsequent calculation of the dissolution rate of the aluminum oxide to be measured in the molten electrolyte, the position and height of the aluminum oxide to be measured placed in the crucible can be limited.

[0051] When the aluminum oxide to be tested is added into the crucible, all of the aluminum oxide samples to be tested fall into the orthographic projection of the reference object on the predetermined projection plane.

[0052] It should be noted that the predetermined projection surface is the interface between the molten electrolyte in the crucible and the air in the heating furnace.

[0053] In some embodiments, the height and position of the discharge port can be adjusted to ensure that all the aluminum oxide samples to be tested fall into the orthographic projection of the reference object on the predetermined projection surface. Of course, other methods can also be used to ensure that all the aluminum oxide samples to be tested fall into the orthographic projection of the reference object on the predetermined projection surface, and the present disclosure does not limit this.

[0054] In some embodiments, it is understood that if no aluminum oxide to be tested covering the reference object is detected, it can directly reflect that all the aluminum oxide to be tested added to the crucible is dissolved in the molten electrolyte.

[0055] Continuing to refer to FIG. 1 , in step 150 , after the aluminum oxide to be tested is added into the crucible, a second image of the reference object in the crucible is acquired in real time.

[0056] In some embodiments, a real-time image of the crucible may be captured at a position directly above the crucible, thereby obtaining a second image at a different time.

[0057] It is understandable that after the addition of the aluminum oxide to be tested is completed, it is necessary to continuously collect the second image of the reference object in the crucible. Since the aluminum oxide to be tested that covers the reference object will continue to dissolve in the molten electrolyte, each second image collected before the aluminum oxide to be tested is completely dissolved in the molten electrolyte is different.

[0058] That is, the information conveyed by the second images acquired at different times is different.

[0059] Continuing to refer to FIG. 1 , in step 160 , the dissolution rate of the aluminum oxide to be tested in the molten electrolyte is determined based on the first image and the second image.

[0060] Step 160 may also include the steps shown in FIG. 2 .

[0061] Referring to Figure 2, there is shown a detailed flow chart of determining the dissolution rate of the aluminum oxide to be tested in the molten electrolyte based on the first image and the second image according to some embodiments of the present disclosure. The process of determining the dissolution rate of the aluminum oxide to be tested in the molten electrolyte based on the first image and the second image may include the following steps 161 to 162.

[0062] Step 161 : Determine a first area of ​​the reference object in the first image, and determine a second area of ​​the reference object in the second image.

[0063] In some embodiments, a first region corresponding to the reference object may be determined from the first image, and then the first area of ​​the reference object in the first image may be obtained by calculating the area of ​​the first region.

[0064] Since the solid electrolyte is a molten electrolyte and the aluminum oxide to be measured has not yet been added to the crucible when the first image is collected, the first area obtained is the surface area of ​​the upper side of the reference object.

[0065] In some embodiments, a second region corresponding to the reference object may be first determined from the second image, and then the second area of ​​the reference object in the second image may be obtained by calculating the area of ​​the second region.

[0066] Because the aluminum oxide to be tested was placed in the crucible when the second image was captured, it partially covered the reference object before it was completely dissolved in the molten electrolyte. Therefore, the second area obtained is the partial surface area of ​​the upper side of the reference object.

[0067] Continuing to refer to FIG. 2 , in step 162 , the dissolution rate is determined according to the ratio of the first area to the second area.

[0068] Step 162 may further include steps 1621 to 1623:

[0069] In step 1621, the time when the aluminum oxide to be tested is added to the crucible is obtained as the first time, and the time corresponding to the acquisition of the second image recorded when the ratio of the first area to the second area is 1 is obtained as the second time.

[0070] In step 1622, the time difference between the second time and the first time is calculated to obtain the dissolution time consumed by the aluminum oxide to be tested to be completely dissolved in the molten electrolyte.

[0071] In step 1623, the ratio of the mass of the aluminum oxide to be tested to the dissolution time is calculated to obtain the dissolution rate.

[0072] It is understandable that if the ratio of the first area to the second area is 1, it means that in the second image, there is no aluminum oxide to be tested that blocks the reference object, which further indicates that the aluminum oxide to be tested in the crucible is completely dissolved in the molten electrolyte.

[0073] It can also be understood that, since the second image is acquired in real time, each second image has a corresponding acquisition time, and thus the second time can be obtained by obtaining the acquisition time corresponding to the second image with a ratio of 1.

[0074] In some embodiments, the time difference between the second time and the first time can accurately reflect the time it takes for the aluminum oxide to be tested to be completely dissolved in the molten electrolyte, that is, the dissolution time.

[0075] In step 1623, the dissolution rate of the aluminum oxide to be tested in the molten electrolyte can be calculated by the following formula (1): V = m / t (1)

[0076] Wherein, V represents the dissolution rate of the aluminum oxide to be tested in the molten electrolyte; m represents the mass of the aluminum oxide to be tested; and t represents the dissolution time.

[0077] According to a second aspect of the present disclosure, a system for measuring the dissolution rate of aluminum oxide in a molten electrolyte is provided.

[0078] The system will be described below with reference to FIG3 to FIG5 .

[0079] See Figure 3, which shows a structural schematic diagram of a system for measuring the dissolution rate of aluminum oxide in a molten electrolyte according to some embodiments of the present disclosure, and see Figure 4, which shows a detailed schematic diagram of a system for measuring the dissolution rate of aluminum oxide in a molten electrolyte according to some embodiments of the present disclosure, and see Figure 5, which shows a detailed schematic diagram of a reference object and a molten electrolyte contained in a crucible according to some embodiments of the present disclosure.

[0080] In some embodiments, the measurement system includes a heating furnace 10 , a feeding unit 40 , an image acquisition unit 20 , and an analysis unit 30 .

[0081] In some embodiments, the heating furnace 10 is used to heat a crucible 50 placed in the heating furnace 10 , wherein the crucible 50 contains a reference object 51 and a solid electrolyte.

[0082] In some embodiments, the heating furnace 10 includes a heating chamber 11 , a temperature collection unit 12 , and a control unit 13 .

[0083] The heating chamber 11 is used to place the crucible 50 .

[0084] The temperature collecting unit 12 is used to collect the temperature inside the heating furnace 10 .

[0085] The control unit 13 is connected to the temperature acquisition unit 12 and is used to adjust the operating parameters of the heating furnace 10 based on the temperature in the heating furnace 10 .

[0086] In some embodiments, the temperature acquisition unit 12 may be a thermocouple disposed between the placed crucible 50 and the inner wall of the heating chamber 11, thereby acquiring the temperature within the heating chamber 11 and transmitting the data to the control unit 13. The control unit 13 can then adjust the heating mode and the heat preservation mode of the heating furnace 10 based on the data acquired by the temperature acquisition unit 12. In some embodiments, the control unit 13 may switch the heating furnace 10 from the heating mode to the heat preservation mode upon determining that the temperature within the heating furnace 10 has reached the target temperature.

[0087] In some embodiments, a top opening 14 communicating with the inner space of the heating chamber 11 is provided on the top of the heating furnace 10 . The top opening 14 can be used as an observation port to facilitate a user to observe the crucible 50 in the heating furnace 10 .

[0088] In some embodiments, the feeding unit 40 in the measurement system is used to add the aluminum oxide to be measured into the crucible 50 after the solid electrolyte becomes the molten electrolyte 52 .

[0089] It is understandable that after determining that the solid electrolyte in the crucible 50 has become the molten electrolyte 52 , the feeding unit 40 can add the pre-weighed aluminum oxide to be tested into the crucible 50 to measure the dissolution rate of the aluminum oxide to be tested in the molten electrolyte 52 .

[0090] In some embodiments, the image acquisition unit 20 in the measurement system is used to capture a first image of the reference object 51 in the crucible 50 when the solid electrolyte becomes a molten electrolyte 52, and is also used to capture a second image of the reference object 51 in the crucible 50 in real time after the aluminum oxide to be measured is added to the crucible 50.

[0091] In some embodiments, the image acquisition unit 20 includes a camera 21 , an adjustment bracket 22 , and a light source supply device 23 .

[0092] In some embodiments, the camera device 21 is disposed above the top opening 14 of the heating furnace 10 to capture an image of the reference object 51 in the crucible 50 .

[0093] It is understandable that arranging the camera device 21 above the top opening 14 of the heating furnace 10 can protect the camera device 21 and accurately capture the image of the reference object 51 in the crucible 50 .

[0094] In some embodiments, an adjustment bracket 22 is connected to the camera device 21 and is used to adjust the distance between the camera device 21 and the heating furnace 10 .

[0095] It is understandable that the adjustment bracket 22 can adjust the height of the camera device 21. Therefore, the position of the camera device 21 can be adjusted according to actual needs so that the camera device 21 can capture a clear image of the reference object 51 in the crucible 50.

[0096] In some embodiments, the light source supply device 23 is used to assist the camera device 21 in capturing the image of the reference object 51 in the crucible 50 .

[0097] It is understandable that the light source supply device 23 can emit a light beam and irradiate the light beam into the heating furnace 10 to assist the camera device 21 in capturing a clear image of the reference object 51 in the crucible 50 .

[0098] In some embodiments, the light source supply device 23 may be connected to a light source bracket 24 , and the position of the light source supply device 23 may be adjusted through the light source bracket 24 .

[0099] In some embodiments, the analysis unit 30 in the measurement system is connected to the image acquisition unit 20 and is configured to determine the dissolution rate of the aluminum oxide to be measured in the molten electrolyte 52 based on the first image and the second image.

[0100] In some embodiments, the analysis unit may be image analysis software installed in a computer.

[0101] The analysis unit 30 can determine the dissolution rate of the aluminum oxide to be tested in the molten electrolyte 52 according to step 160 in the first aspect above, which will not be described in detail in this disclosure.

[0102] In order to enable those skilled in the art to better understand the technical solutions of the present disclosure, seven embodiments are illustrated below.

[0103] Example 1

[0104] The alumina to be tested was obtained from alumina production enterprise 1.

[0105] A reference material and 200 g of a mixture of cryolite (Na3AlF6) and aluminum fluoride were placed in a platinum crucible. Cryolite and aluminum fluoride constitute the electrolyte, and the molecular ratio of sodium fluoride (NaF) to aluminum fluoride in the electrolyte is controlled to be 2.50; the crucible is placed in a heating furnace with a set heating and insulation program and begins to heat up, with a target temperature of 950°C. When the electrolyte in the crucible is completely dissolved and becomes a molten electrolyte, a first image of the reference object is collected. Thereafter, after adding 2g of the aluminum oxide to be tested, a second image of the reference object is collected in real time. Furthermore, the analysis unit calculates that the dissolution rate of the aluminum oxide to be tested is completely dissolved at 0.0016g / s; 2g of the aluminum oxide to be tested is added for the second time to the molten electrolyte in which the aluminum oxide to be tested has been completely dissolved, and the dissolution rate of the aluminum oxide to be tested is analyzed to be completely dissolved at 0.0015g / s; 2g of the aluminum oxide to be tested is added for the third time to the molten electrolyte in which the aluminum oxide to be tested has been completely dissolved, and the dissolution rate of the aluminum oxide to be tested is analyzed to be completely dissolved at 0.0015g / s.

[0106] The alumina dissolution rates obtained from several analyses were added together and the average value was calculated to obtain the target alumina dissolution rate. Thus, the target alumina dissolution rate for the alumina to be tested in Example 1 was calculated to be 0.0015 g / s.

[0107] Example 2

[0108] The alumina to be tested was obtained from alumina production enterprise 1.

[0109] A reference material and 200 g of a mixture of cryolite and aluminum fluoride were placed in a platinum crucible. Cryolite and aluminum fluoride constitute an electrolyte, and the molecular ratio of sodium fluoride (NaF) to aluminum fluoride in the electrolyte is controlled to be 2.70. The crucible is placed in a heating furnace with a set heating and insulation program and begins to heat up. The target temperature is 1000°C. When the electrolyte in the crucible is completely dissolved and becomes a molten electrolyte, a first image of the reference object is collected. Then, 2g of the aluminum oxide to be tested is added. After adding 2g of the aluminum oxide to be tested, a second image of the reference object is collected in real time. Then, the analysis unit calculates that the dissolution rate of the aluminum oxide to be tested is completely dissolved at 0.0020g / s; 2g of the aluminum oxide to be tested is added for the second time to the molten electrolyte in which the aluminum oxide to be tested has been completely dissolved, and the dissolution rate of the aluminum oxide to be tested is analyzed to be completely dissolved at 0.0019g / s; 2g of the aluminum oxide to be tested is added for the third time to the molten electrolyte in which the aluminum oxide to be tested has been completely dissolved, and the dissolution rate of the aluminum oxide to be tested is analyzed to be completely dissolved at 0.0019g / s.

[0110] The alumina dissolution rates obtained from several analyses were added together and the average value was calculated to obtain the target alumina dissolution rate. Thus, the target alumina dissolution rate for the alumina to be tested in Example 2 was calculated to be 0.0019 g / s.

[0111] Example 3

[0112] The alumina to be tested was obtained from alumina production enterprise 2.

[0113] A reference object and 100 g of factory electrolyte were added to a platinum crucible. In the factory electrolyte, the molecular ratio of sodium fluoride to aluminum fluoride was 2.45, and the initial mass percentage of aluminum oxide was 2.5%. The crucible was placed in a heating furnace set with a heating and insulation program and began to heat up. The target temperature was 945°C. When the factory electrolyte in the crucible was completely dissolved and turned into molten factory electrolyte, a first image of the reference object was captured. Then, 1 g of aluminum oxide to be tested was added. After adding 1 g of aluminum oxide to be tested, a second image of the reference object was captured in real time. Furthermore, the analysis unit calculated that the dissolution rate of the aluminum oxide to be tested was completely dissolved at 0.0009 g / s. 1 g of aluminum oxide to be tested was added a second time to the molten factory electrolyte in which the aluminum oxide to be tested had been completely dissolved. The dissolution rate of the aluminum oxide to be tested was analyzed to be 0.0009 g / s. 1 g of aluminum oxide to be tested was added a first time to the molten electrolyte in which the aluminum oxide to be tested had been completely dissolved. The dissolution rate of the aluminum oxide to be tested was analyzed to be 0.0009 g / s.

[0114] The alumina dissolution rates obtained from several analyses were added together and the average value was calculated to obtain the target alumina dissolution rate. Thus, the target alumina dissolution rate for the alumina to be tested in Example 3 was calculated to be 0.0009 g / s.

[0115] Example 4

[0116] The alumina to be tested was obtained from alumina production enterprise 2.

[0117] A reference object and a mixture of 100g of potassium fluoride, sodium fluoride, aluminum fluoride and aluminum oxide were added to a platinum crucible. Potassium fluoride, sodium fluoride, aluminum fluoride and aluminum oxide constituted an electrolyte, and the molecular ratio of alkali metal fluorides (NaF and KF) to aluminum fluoride in the electrolyte was controlled to be 1.90, and the initial mass percentage of aluminum oxide was 2.0%. The crucible was placed in a heating furnace with a set heating and insulation program and began to heat up. The target temperature was 890°C. When the electrolyte in the crucible was completely dissolved and turned into a molten electrolyte, the first image of the reference object was collected. After that, 1g of the aluminum oxide to be tested was added. After adding 1g of the aluminum oxide to be tested, the image was taken in real time. A second image of the reference object is captured, and then the analysis unit calculates that the dissolution rate of the aluminum oxide to be tested is completely dissolved at 0.0006 g / s; 1 g of the aluminum oxide to be tested is added for the second time to the molten electrolyte in which the aluminum oxide to be tested has been completely dissolved, and the analysis shows that the dissolution rate of the aluminum oxide to be tested is completely dissolved at 0.0006 g / s; 1 g of the aluminum oxide to be tested is added for the first time to the molten electrolyte in which the aluminum oxide to be tested has been completely dissolved, and the analysis shows that the dissolution rate of the aluminum oxide to be tested is completely dissolved at 0.0006 g / s.

[0118] The alumina dissolution rates obtained from several analyses were added together and the average value was calculated to obtain the target alumina dissolution rate. Thus, the target alumina dissolution rate for the alumina to be tested in Example 4 was calculated to be 0.0006 g / s.

[0119] Example 5

[0120] The alumina to be tested was obtained from alumina production enterprise 2.

[0121] A reference object and a mixture of 100g of potassium fluoride, sodium fluoride, aluminum fluoride and aluminum oxide were added to a platinum crucible. Potassium fluoride, sodium fluoride, aluminum fluoride and aluminum oxide constituted an electrolyte, and the molecular ratio of alkali metal fluorides (NaF and KF) to aluminum fluoride in the electrolyte was controlled to be 1.35, and the initial mass percentage of aluminum oxide was 2.5%. The crucible was placed in a heating furnace with a set heating and insulation program and began to heat up. The target temperature was 750°C. When the electrolyte in the crucible was completely dissolved and turned into a molten electrolyte, the first image of the reference object was collected. After that, 1g of the aluminum oxide to be tested was added. After adding 1g of the aluminum oxide to be tested, the actual image was taken. A second image of the reference object is captured, and then the analysis unit calculates that the dissolution rate of the aluminum oxide to be tested is completely dissolved at 0.0005 g / s; 1 g of the aluminum oxide to be tested is added for the second time to the molten electrolyte in which the aluminum oxide to be tested has been completely dissolved, and it is analyzed that the dissolution rate of the aluminum oxide to be tested is completely dissolved at 0.0005 g / s; 1 g of the aluminum oxide to be tested is added for the first time to the molten electrolyte in which the aluminum oxide to be tested has been completely dissolved, and it is analyzed that the dissolution rate of the aluminum oxide to be tested is completely dissolved at 0.0005 g / s.

[0122] The alumina dissolution rates obtained from several analyses were added together and the average value was calculated to obtain the target alumina dissolution rate. Thus, the target alumina dissolution rate for the alumina to be tested in Example 5 was calculated to be 0.0005 g / s.

[0123] Example 6

[0124] The alumina to be tested was obtained from alumina production enterprise 1.

[0125] The reference and 200 g of a mixture of cryolite and aluminum fluoride were added to a silicon carbide crucible. Cryolite and aluminum fluoride constitute an electrolyte, and the molecular ratio of sodium fluoride (NaF) to aluminum fluoride in the electrolyte is controlled to be 2.50; the crucible is placed in a heating furnace set with a heating and insulation program and begins to heat up, with a target temperature of 950°C. When the electrolyte in the crucible is completely dissolved and becomes a molten electrolyte, a first image of the reference object is collected, and then 2g of the aluminum oxide to be tested is added. After adding 2g of the aluminum oxide to be tested, a second image of the reference object is collected in real time, and then, the analysis unit calculates that the dissolution rate of the aluminum oxide to be tested is completely dissolved at 0.0015g / s; 2g of the aluminum oxide to be tested is added for the second time to the molten electrolyte in which the aluminum oxide to be tested has been completely dissolved, and the dissolution rate of the aluminum oxide to be tested is analyzed to be completely dissolved at 0.0015g / s; 2g of the aluminum oxide to be tested is added for the third time to the molten electrolyte in which the aluminum oxide to be tested has been completely dissolved, and the dissolution rate of the aluminum oxide to be tested is analyzed to be completely dissolved at 0.0015g / s.

[0126] The alumina dissolution rates obtained from several analyses were summed and averaged to obtain the target alumina dissolution rate. Thus, the target alumina dissolution rate for the alumina to be tested in Example 6 was calculated to be 0.0015 g / s.

[0127] Example 7

[0128] The alumina to be tested was obtained from alumina production enterprise 1.

[0129] A reference material and 200 g of a mixture of cryolite and aluminum fluoride were placed in a quartz crucible. Cryolite and aluminum fluoride constitute the electrolyte, and the molecular ratio of sodium fluoride (NaF) to aluminum fluoride in the electrolyte is controlled to be 2.50. The crucible is placed in a heating furnace with a set heating and insulation program and starts to heat up. The target temperature is 950°C. When the electrolyte in the crucible is completely dissolved and becomes a molten electrolyte, the first image of the reference object is collected. Then, 2g of the aluminum oxide to be tested is added. After adding 2g of the aluminum oxide to be tested, the second image of the reference object is collected in real time. Then, the analysis unit calculates that the dissolution rate of the aluminum oxide to be tested is completely dissolved at 0.0016g / s; 2g of the aluminum oxide to be tested is added for the second time to the molten electrolyte in which the aluminum oxide to be tested has been completely dissolved, and the dissolution rate of the aluminum oxide to be tested is analyzed to be completely dissolved at 0.0015g / s; 2g of the aluminum oxide to be tested is added for the third time to the molten electrolyte in which the aluminum oxide to be tested has been completely dissolved, and the dissolution rate of the aluminum oxide to be tested is analyzed to be completely dissolved at 0.0015g / s.

[0130] The alumina dissolution rates obtained from several analyses were summed and averaged to obtain the target alumina dissolution rate. Thus, the target alumina dissolution rate for the alumina to be tested in Example 7 was calculated to be 0.0015 g / s.

[0131] The seven aforementioned examples demonstrate that the dissolution rate of the aluminum oxide to be tested in the molten electrolyte is related to factors such as the type of solid electrolyte, the target temperature, and the mass of the added aluminum oxide to be tested. Therefore, in the present disclosure, the dissolution rate of the aluminum oxide to be tested can be controlled under predetermined conditions to be measured, based on the requirements of the aluminum electrolysis process.

[0132] In addition, it can be seen from the above seven embodiments that the technical solution disclosed in the present invention has the advantages of high accuracy and good repeatability when measuring the dissolution rate of the aluminum oxide to be measured in the molten electrolyte.

[0133] In the technical solutions provided in some embodiments of the present disclosure, in the process of measuring the dissolution rate of aluminum oxide in a molten electrolyte, first, a crucible containing a reference object and a solid electrolyte is placed in a heating furnace; second, the heating furnace is controlled to heat the crucible; third, when the solid electrolyte becomes a molten electrolyte, a first image of the reference object in the crucible is collected; third, the aluminum oxide to be measured is added to the crucible; and after the aluminum oxide to be measured is added to the crucible, a second image of the reference object in the crucible is collected in real time; finally, based on the first image and the second image, the dissolution rate of the aluminum oxide to be measured in the molten electrolyte is determined.

[0134] It can be seen that based on the technical solution of the present disclosure, the process of determining the dissolution rate of aluminum oxide in the molten electrolyte is an automated analysis process that does not require the intervention of analysis and detection personnel. Therefore, to a certain extent, it can reduce the labor intensity of analysis and detection personnel and reduce the complexity of determining the dissolution rate of aluminum oxide in the molten electrolyte. In addition, in the technical solution of the present disclosure, by placing a reference object in the crucible, during the measurement process, it is only necessary to collect an image of the reference object, and then automatically analyze the image of the reference object to obtain the dissolution rate of the aluminum oxide to be measured in the molten electrolyte. Therefore, the measurement method of the present disclosure does not require complex equipment investment, and the measurement process is simple, with high measurement accuracy and repeatability. It can effectively reduce the complexity of determining the dissolution rate of aluminum oxide in the molten electrolyte and has promotion value.

[0135] The foregoing description is merely an embodiment of the present disclosure and is not intended to limit the present disclosure. Various modifications and variations are readily apparent to those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present disclosure are intended to be within the scope of the claims of the present disclosure.

Claims

1. A method for determining the dissolution rate of aluminum oxide in a molten electrolyte, comprising: The crucible containing the reference material and the solid electrolyte is placed in a heating furnace; controlling the heating furnace to heat the crucible; When the solid electrolyte becomes a molten electrolyte, collecting a first image of the reference object in the crucible; Adding aluminum oxide to be tested into the crucible; After adding the aluminum oxide to be tested into the crucible, collecting a second image of the reference object in the crucible in real time; as well as Based on the first image and the second image, a dissolution rate of the aluminum oxide to be tested in the molten electrolyte is determined.

2. The method according to claim 1, wherein Controlling the heating furnace to heat the crucible includes: controlling the heating furnace to heat the crucible according to a temperature rising mode, and collecting the temperature in the heating furnace in real time; and When the temperature in the heating furnace reaches a target temperature, the heating furnace is controlled to switch from the temperature rising mode to the temperature keeping mode.

3. The method according to claim 1, wherein Determining a dissolution rate of the aluminum oxide to be tested in the molten electrolyte based on the first image and the second image includes: determining a first area of ​​the reference object in the first image, and determining a second area of ​​the reference object in the second image; and The dissolution rate of the aluminum oxide to be tested is determined according to the ratio of the first area to the second area.

4. The method according to claim 3, wherein: Determining the dissolution rate of the aluminum oxide to be tested according to the ratio of the first area to the second area includes: Obtaining the time when the aluminum oxide to be tested is added to the crucible as a first time, and obtaining the time corresponding to the acquisition of the second image recorded when the ratio of the first area to the second area is 1 as a second time; Calculating the time difference between the second time and the first time to obtain the dissolution time of the aluminum oxide to be tested completely dissolved in the molten electrolyte; and The ratio of the mass of the aluminum oxide to be tested to the dissolution time is calculated to obtain the dissolution rate.

5. The method according to claim 1, wherein When the aluminum oxide to be tested is added into the crucible, all of the aluminum oxide samples to be tested fall into the orthographic projection of the reference object on the predetermined projection plane.

6. The method according to claim 1, wherein The material of the reference object is one of platinum and nickel, and the shape of the reference object is one of a sheet shape, a straight line shape, a ring shape, and a mesh shape.

7. The method according to claim 1, wherein The crucible is made of one of platinum, silicon carbide and quartz.

8. A system for measuring the dissolution rate of aluminum oxide in a molten electrolyte, comprising: A heating furnace, used to heat a crucible placed in the heating furnace, wherein the crucible contains a reference material and a solid electrolyte; a feeding unit, used for adding the aluminum oxide to be tested into the crucible after the solid electrolyte becomes a molten electrolyte; an image acquisition unit, configured to acquire a first image of the reference object in the crucible when the solid electrolyte becomes a molten electrolyte, and further configured to acquire a second image of the reference object in the crucible in real time after the aluminum oxide to be tested is added to the crucible; as well as An analysis unit connected to the image acquisition unit is used to determine the The dissolution rate of the aluminum oxide to be tested in the molten electrolyte.

9. The system according to claim 8, wherein: The heating furnace comprises: a heating chamber for placing the crucible; a temperature collecting unit, configured to collect the temperature in the heating furnace; and A control unit is connected to the temperature acquisition unit and is used to adjust the operating parameters of the heating furnace based on the temperature in the heating furnace.

10. The system according to claim 9, wherein: The top of the heating furnace is provided with a top opening communicating with the inner space of the heating chamber, and the image acquisition unit includes: a camera device, disposed above the top opening of the heating furnace, for capturing an image of the reference object in the crucible; an adjusting bracket, connected to the camera device, and used to adjust the distance between the camera device and the heating furnace; and A light source supply device is used to assist the camera device in capturing an image of the reference object in the crucible.

Images