Device and method for adjusting position of anode of rare earth electrolytic furnace

Abstract

The invention relates to the technical field of rare earth electrolytic furnaces, in particular to rare earth electrolytic furnace anode position adjusting equipment and an adjusting method.The rare earth electrolytic furnace anode position adjusting equipment comprises an electrolytic furnace and a working assembly, and the working assembly comprises a cathode bar, a plurality of current density monitoring sensors and a plurality of anode adjusting parts; the cathode bar is arranged on the inner side of the electrolytic furnace; the plurality of current density monitoring sensors are respectively arranged on the surface of the cathode bar; the anode adjusting part comprises a driving unit and an anode plate, the driving unit is arranged on the outer side of the electrolytic furnace, and the anode plate is arranged on the side, close to the electrolytic furnace, of the driving unit; according to the invention, the current density can be monitored in real time, the anode position of the electrolytic furnace can be dynamically adjusted, and the problem of polar distance increase caused by anode consumption can be effectively inhibited, so that stable electric field intensity between the cathode and the anode is maintained, the current density per unit area is improved, and the reduction efficiency of metal ions is enhanced.

Description

Technical Field

[0001] The present invention relates to the technical field of rare earth electrolytic furnaces, and in particular to a device and a method for adjusting the anode position of a rare earth electrolytic furnace. Background Art

[0002] The molten salt electrolysis process of rare earth metals is usually carried out under extremely high temperature conditions exceeding 1000°C. The electrolyte used is a high-temperature molten salt system. This environment places extremely high demands on the structural stability and corrosion resistance of the electrolysis system.

[0003] Traditional electrolytic furnaces usually use a four-piece rigidly fixed graphite anode structure, whose main advantages are high electrical conductivity, good high-temperature resistance, abundant resources and low processing cost. However, during continuous high-temperature electrolysis, the graphite anode reacts with oxygen or chlorine to produce CO or CO2 gas. This process causes the graphite anode to be gradually consumed, and the thickness and volume of the anode continue to decrease, which manifests as the "anode thinning" phenomenon. With the gradual loss of anode material, the anode surface continues to recede, and the actual effective distance between the cathode and cathode (i.e., the inter-electrode distance) gradually increases relative to the position of the fixed cathode. The increase in the inter-electrode distance changes the originally designed spatial geometric relationship of the electrodes, causing changes in the local electric field distribution. This dynamic offset not only causes the current transmission path between the cathode and cathode to be lengthened, but also significantly affects the overall current distribution and resistance characteristics of the electrolysis system. Specifically, the increase in the inter-electrode distance leads to a decrease in the current density per unit area, an increase in the electrolyte resistance, an increase in the electrolysis energy consumption, a weakening of the driving force of the electrolysis reaction, and a subsequent decrease in the reaction rate. Furthermore, in actual operation, the four evenly distributed anode plates often consume at inconsistent rates due to microscopic variations in current density, gas escape paths, and local flow field disturbances. This results in varying variations in the inter-electrode spacing between the four anode plates and the cathode. This uneven consumption leads to non-uniform current density distribution on the cathode surface, resulting in a series of engineering problems such as abnormal current shunting, uneven metal reduction, and reduced anode efficiency.

[0004] The existing technology relies on manual experience to perform intermittent anode position calibration, which has an operation lag period of up to several hours. Summary of the Invention

[0005] The purpose of the present invention is to provide an anode position adjustment device and adjustment method for a rare earth electrolytic furnace, which can monitor the current density in real time and dynamically adjust the anode position of the electrolytic furnace, and can effectively suppress the problem of pole distance growth caused by anode consumption, thereby maintaining a stable electric field strength between the anode and the cathode, improving the current density per unit area, and enhancing the reduction efficiency of metal ions.

[0006] To achieve the above-mentioned object, in a first aspect, the present invention provides an anode position adjustment device for a rare earth electrolytic furnace, comprising an electrolytic furnace and a working assembly, wherein the working assembly comprises a cathode rod, a plurality of current density monitoring sensors, and a plurality of anode adjustment components;

[0007] The cathode rod is arranged on the inside of the electrolytic furnace, and multiple current density monitoring sensors are respectively arranged on the surface of the cathode rod; multiple anode adjustment components are respectively located on the side of the electrolytic furnace, and the anode adjustment components include a driving unit and an anode plate. The driving unit is arranged on the outside of the electrolytic furnace, and the anode plate is arranged on the side of the driving unit close to the electrolytic furnace.

[0008] In which, the drive unit includes a shell, a ball screw, a sleeve and a slide plate; the shell is arranged on the outside of the electrolytic furnace; the ball screw is arranged on the inside of the shell; the sleeve is arranged on the side of the ball screw, and the sleeve is slidably connected to the shell; the slide plate is fixedly connected to the sleeve, and is fixedly connected to the anode plate, and is located between the sleeve and the anode plate.

[0009] Wherein, the drive unit further includes a motor mounting compartment and a flange; the motor mounting compartment is fixedly connected to the shell and is located on the side of the shell; the flange is fixedly connected to the motor mounting compartment and is located inside the motor mounting compartment.

[0010] In which, the current density monitoring sensor includes a shell, a solid electrolyte, two electrodes, two connecting parts, two welding parts, a dielectric layer, a thermocouple and a fiber layer; the shell is arranged on the surface of the cathode rod; the solid electrolyte is arranged in the center of the shell; the two electrodes are arranged on both sides of the solid electrolyte and in contact with the solid electrolyte; the two connecting parts are respectively connected to the two electrodes and are respectively located at the bottom of the two electrodes; the two welding parts are respectively arranged at the bottom of the two connecting parts; the dielectric layer is arranged between the electrode and the connecting part; the thermocouple is arranged on one side of the dielectric layer; and the fiber layer is arranged inside the shell.

[0011] In a second aspect, the present invention further provides a method for adjusting the anode position of a rare earth electrolysis furnace, comprising:

[0012] The current density between the electrolyte, cathode rod and anode plate is monitored in real time by the current density monitoring sensor, and the current density is fed back to the controller in real time;

[0013] The controller calculates the anode target position according to the current density distribution, and controls the driving unit to drive the anode plate to move to the anode target position according to the calculated anode target position.

[0014] The controller calculates the anode target position according to the current density distribution, and controls the driving unit to drive the anode plate to move to the anode target position according to the calculated anode target position. The specific steps include:

[0015] Perform RSI calculation to calculate the distribution of current current density and compare it with the set target current density to obtain the deviation. Set a threshold to determine whether the deviation exceeds the threshold.

[0016] Calculate the Reaction Strength Index (RSI) using the following formula:

[0017]

[0018] Among them J avg is the current average current density in the anode area, d is the real-time inter-electrode distance, T is the electrolyte temperature, and V is the cell voltage;

[0019] Calculate the deviation value e(k) of the Reaction Strength Index RSI using the following formula:

[0020] e(k)=[(RSI,set)-(RSI,actual)]

[0021] Among them, RSI,set is the set value of RSI, and RSI,actual is the actual value of RSI;

[0022] Calculate the deviation value change rate Δe(k) using the following formula:

[0023] Δe(k)=e(k)-e(k-1)

[0024] The deviation and the rate of change of the deviation are used as inputs, and the fuzzy PID algorithm is used to output the anode displacement ΔS, where ΔS is adjusted according to the set threshold. If the current density in a certain anode area is higher than the set threshold, the control drive unit moves the anode plate outward to increase the spacing; if the current density in a certain anode area is lower than the set threshold, the control drive unit pushes the anode plate inward to reduce the spacing.

[0025] The present invention provides an anode position adjustment device and adjustment method for a rare earth electrolytic furnace. The electrolytic furnace serves as a carrier for rare earth electrolysis reaction, contains molten electrolyte, and rare earth metal compounds dissolve therein to form ions; the cathode rod serves as a cathode and is connected to the negative electrode of a power supply, attracting positively charged rare earth metal cations, and electron transfer reduces them to metal elements; the anode plate serves as an anode and is connected to the positive electrode of a power supply, and an oxidation reaction occurs; the current density monitoring sensor is used to monitor the current density between the electrolyte, cathode rod and anode plate in real time, and to provide real-time feedback; the electrolytic furnace is a cylindrical structure, and has independently movable anode adjustment components in four directions of the electrolytic furnace; the bottom of the electrolytic furnace is provided with a crucible slot for placing a crucible, and the crucible is placed in the furnace of the electrolytic furnace. There is a vertically fixed high-purity rare earth metal cathode rod (made of tungsten-molybdenum alloy) at the center of the body. The current density monitoring sensor is embedded in the cathode rod in a grid-like distributed manner. The current density monitoring sensor monitors the current density in real time and feeds back the deviation to the control system in real time for displacement compensation. Specifically, the initial spacing between the anode plate and the cathode rod is set to 10 cm, and the target current density range is input; during operation, the high-precision current density monitoring sensor array with a grid distribution on the surface of the cathode rod monitors the four-quadrant current density distribution in real time; when the electrolytic furnace is electrolyzing, rare earth powder is added to the electrolytic furnace, the graphite anode plate reacts with oxygen to generate CO or CO2, and the rare earth metal is precipitated on the cathode rod and then falls into the crucible at the bottom of the electrolytic furnace. As electrolysis time increases, the graphite anode plate gradually becomes thinner, the inter-electrode distance between the anode plate and the cathode rod increases, the effective inter-electrode distance dynamically shifts, the current density between the anode plate and the cathode rod decreases, the electrolyte resistance increases, and the current density monitoring sensor detects a decrease in current density in real time. When the deviation exceeds ±10% or the inter-electrode distance error is greater than ±0.5mm, a displacement instruction is generated based on a fuzzy PID algorithm (adaptive adjustment of proportional-integral-differential parameters) to drive the target anode to move radially (forward / backward) at a speed of 1mm / s. The other three anodes perform compensatory displacement by detecting current density, so that the annular electric field strength formed by the four anodes is always in the optimal electrolysis state. The drive unit adopts a communication protocol and realizes four-axis synchronous control by a multi-axis motion controller to ensure timely transmission of displacement instructions, ultimately achieving the industrial effects of uniform electrolysis reaction current density, stable control of anode-cathode distance, and extended anode life. The present invention can monitor current density in real time and dynamically adjust the anode position of the electrolytic furnace, effectively suppressing the inter-electrode distance growth problem caused by anode consumption, thereby maintaining a stable electric field strength between the anode and cathode, improving the current density per unit area, and enhancing the reduction efficiency of metal ions. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art.

[0027] Figure 1It is a structural schematic diagram of the anode position adjustment device of the rare earth electrolytic furnace of the present invention.

[0028] Figure 2 It is a cross-sectional view of the anode position adjustment device of the rare earth electrolytic furnace of the present invention.

[0029] Figure 3 It is a structural schematic diagram of the anode adjustment component of the present invention.

[0030] Figure 4 It is a structural schematic diagram of the cathode rod and current density monitoring sensor of the present invention.

[0031] Figure 5 It is a structural schematic diagram of the current density monitoring sensor of the present invention.

[0032] Figure 6 It is a structural schematic diagram of the current density monitoring sensor of the present invention from another perspective.

[0033] Figure 7 The present invention is a flowchart of the operation of the anode position adjustment device for a rare earth electrolytic furnace.

[0034] Figure 8 The present invention is a flow chart of a method for adjusting the anode position of a rare earth electrolytic furnace.

[0035] 1-electrolytic furnace, 2-cathode rod, 3-current density monitoring sensor, 4-anode adjustment component, 10-electrolytic cell, 31-housing, 32-solid electrolyte, 33-electrode, 34-connecting part, 35-welding part, 36-dielectric layer, 37-thermocouple, 38-fiber layer, 41-drive unit, 42-anode plate, 411-housing, 412-ball screw, 413-sleeve, 414-slide plate, 415-motor mounting compartment, 416-flange. DETAILED DESCRIPTION

[0036] The embodiments of the present invention are described in detail below. Examples of the embodiments are shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, but should not be understood as limiting the present invention.

[0037] First, see Figure 1-Figure 7The present invention provides an anode position adjustment device for a rare earth electrolytic furnace, comprising an electrolytic furnace 1 and a working component, wherein the working component comprises a cathode rod 2, multiple current density monitoring sensors 3 and multiple anode adjustment components 4; the anode adjustment component 4 comprises a drive unit 41 and an anode plate 42, wherein the drive unit 41 comprises a shell 411, a ball screw 412, a sleeve 413, a slide plate 414, a motor mounting compartment 415 and a flange 416; the current density monitoring sensor 3 comprises a shell 31, a solid electrolyte 32, two electrodes 33, two connecting parts 34, two welding parts 35, a dielectric layer 36, a thermocouple 37 and a fiber layer 38; through the above-mentioned scheme, the current density can be monitored in real time, the anode position of the electrolytic furnace 1 can be dynamically adjusted, and the problem of pole distance growth caused by anode consumption can be effectively suppressed, thereby maintaining a stable electric field strength between the anode and the cathode, improving the current density per unit area, and enhancing the reduction efficiency of metal ions.

[0038] According to this specific embodiment, the cathode rod 2 is arranged on the inner side of the electrolytic furnace 1, and the multiple current density monitoring sensors 3 are respectively arranged on the surface of the cathode rod 2; the multiple anode adjustment components 4 are respectively located on the side of the electrolytic furnace 1, and the anode adjustment components 4 include a drive unit 41 and an anode plate 42, the drive unit 41 is arranged on the outside of the electrolytic furnace 1, and the anode plate 42 is arranged on the side of the drive unit 41 close to the electrolytic furnace 1. The number of the anode adjustment components 4 is preferably four, and an electrolytic cell 10 is provided in the electrolytic furnace 1. The electrolytic furnace 1 serves as a carrier for the rare earth electrolysis reaction, accommodating a molten electrolyte in which rare earth metal compounds dissolve to form ions; the cathode rod 2 serves as a cathode connected to the negative pole of the power supply, attracting positively charged rare earth metal cations, and electron transfer reduces them to metal elements; the anode plate 42 serves as an anode connected to the positive pole of the power supply, and an oxidation reaction occurs; the current density monitoring sensor 3 is used to monitor the current density between the electrolyte, the cathode rod 2 and the anode plate 42 in real time, and to provide real-time feedback; the electrolytic furnace 1 is a cylindrical structure, and the electrolytic furnace 1 has independently movable anode adjustment components 4 in four directions, and a crucible tank with a crucible is provided at the bottom of the electrolytic furnace 1. There is a vertically fixed high-purity rare earth metal cathode rod 2 (made of tungsten-molybdenum alloy) in the center of the furnace body. The current density monitoring sensor 3 is embedded in the cathode rod 2 in a grid-like distributed manner. The current density monitoring sensor 3 monitors the current density in real time and feeds back the deviation to the control system in real time for displacement compensation. Specifically, the initial spacing between the anode plate 42 and the cathode rod 2 is set to 10 cm, and the target current density range is input; during operation, the high-precision current density monitoring sensor 3 array distributed in a grid on the surface of the cathode rod 2 monitors the four-quadrant current density distribution in real time; when the electrolytic furnace 1 is electrolyzing, rare earth powder is added to the electrolytic furnace 1, and the graphite anode plate 42 reacts with oxygen to generate CO or CO2. The rare earth metal is precipitated on the cathode rod 2 and then falls into the crucible at the bottom of the electrolytic furnace 1.As the electrolysis time increases, the graphite anode plate 42 gradually becomes thinner, the inter-electrode distance between the anode plate 42 and the cathode rod 2 increases, the effective inter-electrode distance dynamically shifts, the current density between the anode plate 42 and the cathode rod 2 decreases, the electrolyte resistance increases, and the current density monitoring sensor 3 detects the current density decrease in real time. When the deviation exceeds ±10% or the inter-electrode distance error is greater than ±0.5mm, a displacement instruction is generated based on the fuzzy PID algorithm (proportional-integral-differential parameter adaptive adjustment) to drive the target anode to move radially (forward / backward) at a speed of 1mm / s. The other three anodes perform compensation by detecting the current density. The invention can monitor the current density in real time, dynamically adjust the anode position of the electrolytic furnace 1, and effectively suppress the problem of pole distance growth caused by anode consumption, thereby maintaining a stable electric field strength between the anode and the cathode, improving the current density per unit area, and enhancing the reduction efficiency of metal ions.

[0039] Among them, the shell 411 is arranged on the outside of the electrolytic furnace 1; the ball screw 412 is arranged on the inside of the shell 411; the sleeve 413 is arranged on the side of the ball screw 412, and the sleeve 413 is slidingly connected to the shell 411; the slide plate 414 is fixedly connected to the sleeve 413, and is fixedly connected to the anode plate 42, and is located between the sleeve 413 and the anode plate 42. The slide plate 414 serves as a carrier of the anode plate 42, and the boss at the bottom of the slide plate 414 can slide back and forth on the track at the top of the electrolytic furnace 1; the ball screw 412 model is HIWIN EGW20B05T3F0ZC; the end of the screw on the ball screw 412 is fixedly connected to the output shaft of the stepper motor, and the sleeve 413 is fixedly connected to the nut on the ball screw 412, and the sleeve 413 is installed on the shell 411, and the sleeve 413 can slide along the shell 411, and the shell 411 can limit the rotation of the sleeve 413, and the ball screw 412 is driven to rotate by the stepper motor, and the ball screw 412 converts the rotational motion into linear motion, so that the sleeve 413 moves linearly along the shell 411, and the sleeve 413 drives the anode plate 42 to move through the slide plate 414 to achieve position adjustment of the anode plate 42.

[0040] Next, the motor mounting compartment 415 is fixedly connected to the housing 411 and located on the side of the housing 411. The flange 416 is fixedly connected to the motor mounting compartment 415 and located inside the motor mounting compartment 415. The mounting compartment is used to mount a stepper motor. The end of the upper screw of the ball screw 412 is fixedly connected to the output shaft of the stepper motor. The motor model is PKP569D2A-SG10, with a torque of 5.6 N·m. The flange 416 is used to connect to the stepper motor.

[0041] Finally, the outer shell 31 is disposed on the surface of the cathode rod 2; the solid electrolyte 32 is disposed in the center of the outer shell 31; the two electrodes 33 are disposed on either side of the solid electrolyte 32 and in contact with the solid electrolyte 32; the two connecting portions 34 are respectively connected to the two electrodes 33 and located at the bottom of the two electrodes 33; the two welding portions 35 are respectively disposed at the bottom of the two connecting portions 34; the dielectric layer 36 is disposed between the electrodes 33 and the connecting portions 34; the thermocouple 37 is disposed on one side of the dielectric layer 36; and the fiber layer 38 is disposed within the outer shell 31. The outer shell 31 is made of Al2O3 and serves to protect the current density monitoring sensor 3 from damage and corrosion due to high temperatures. The fiber layer 38 is also enclosed in the outer shell. The welding portion 35 and the side of the current density monitoring sensor 3 are directly embedded in the cathode rod 2 and secured with high-temperature ceramic glue. The solid electrolyte 32 material adopts solid electrolyte 32 (yttria-stabilized zirconia ceramic), which allows oxygen ions to move between the electrodes 33 and has excellent high-temperature stability (>1000°C) and ionic conductivity. The electrode 33 material adopts platinum-iridium alloy (Pt-Ir), which takes into account both high-temperature corrosion resistance and conductivity. Preferably, an Al2O3 coating can be applied to the surface of the electrode 33 to enhance the corrosion resistance of molten salts and electrolytes. The connecting portion 34 is used to connect the electrode 33 to an external circuit to transmit electrical signals. It is located on the outside of the dielectric layer 36 and is fixed by a welding portion 35. The welding portion 35 is used to fix the connecting portion 34 to ensure a stable connection between the electrode 33 and the external circuit. The dielectric layer 36 has an insulating effect, preventing the electrode 33 from direct contact with other components while allowing ions to pass through. The thermocouple 37 adopts a Pt-Rh thermocouple 37, which is used for temperature measurement or as a heating element to ensure that the current density monitoring sensor 3 operates at the optimal working temperature. It is located on one side of the current density monitoring sensor 3 and is isolated from the electrode 33 by the dielectric layer 36. The fiber layer 38 is used to enhance the structural strength of the sensor and serve as a supporting structure. The current density monitoring sensor 3 is distributed and embedded in the surface of the cathode rod 2. The solid electrolyte 32 and the electrode 33 are integrated into one piece by a co-sintering process to avoid high-temperature interface failure. The current density is measured by the electrolyte potential difference method, and the current-voltage relationship model is established using the oxygen ion migration characteristics of the solid electrolyte 32. The solid electrolyte 32 becomes oxygen ions (O 2-) conductor. The oxygen vacancies in its crystal structure allow oxygen ions to migrate through a vacancy hopping mechanism, while the electronic conductivity is extremely low. This property makes it an ideal "ion-selective transport medium." When the two ends of the solid electrolyte 32 are in contact with environments with different oxygen chemical potentials (i.e., between the surface of the cathode rod 2 and the electrolyte of the electrolytic furnace), oxygen ions will migrate from the high chemical potential area to the low chemical potential area. According to the Nernst equation, this migration will form a potential difference (ΔE) on both sides of the solid electrolyte 32, calculated as:

[0042]

[0043] Where R is the gas constant, T is the temperature, and F is the Faraday constant. is the oxygen partial pressure, ref is the reference end (i.e., the cathode surface environment), and sample is the sample end (i.e., the electrolyte environment of the electrolytic furnace 1 to be tested).

[0044] During the electrolysis process, the current density j on the cathode surface is directly related to the oxygen ion migration rate. According to Faraday's law:

[0045]

[0046] Where z is the charge number of the oxygen ion (z=2), is the oxygen ion flux. It can be calculated by the ionic conductivity of the solid electrolyte 32 and the electric field strength (E = ΔV / d, d is the thickness of the solid electrolyte 32):

[0047]

[0048] Combining the above two equations, a linear model of j∝ΔV can be established.

[0049] Signal Transmission Solution: The high-temperature conductor of the current density monitoring sensor 3 utilizes molybdenum-coated platinum (Mo / Pt) wire, coated with a boron nitride insulation layer. This conductor withstands temperatures up to 1100°C and protects against electrolyte corrosion. Signal processing converts the current signal into a digital quantity, which is then transmitted to the controller via the potential difference detected by the current density monitoring sensor 3 to avoid high-temperature electromagnetic interference. The current density monitoring sensor 3 is embedded in the cathode rod 2, with a prefabricated grid array of holes. The current density monitoring sensor 3 is secured with high-temperature ceramic adhesive to ensure full contact with the electrolyte.

[0050] The anode position adjustment device of the rare earth electrolytic furnace of the present invention, the electrolytic furnace 1 serves as a carrier of the rare earth electrolysis reaction, contains a molten electrolyte, and rare earth metal compounds are dissolved therein to form ions; the cathode rod 2 serves as a cathode connected to the negative pole of the power supply, attracts positively charged rare earth metal cations, and electron transfer reduces them to metal elements; the anode plate 42 serves as an anode connected to the positive pole of the power supply, and an oxidation reaction occurs; the current density monitoring sensor 3 is used to monitor the current density between the electrolyte, the cathode rod 2 and the anode plate 42 in real time, and to provide real-time feedback; the electrolytic furnace 1 is a cylindrical structure, and the electrolytic furnace 1 has independently movable anode adjustment components 4 in four directions, the bottom of the electrolytic furnace 1 has a crucible tank for placing a crucible, and a vertical A high-purity rare earth metal cathode rod 2 (made of tungsten-molybdenum alloy) is fixed vertically, and a current density monitoring sensor 3 is embedded in the cathode rod 2 in a grid-like distributed manner. The current density monitoring sensor 3 monitors the current density in real time and feeds back the deviation to the control system in real time for displacement compensation. Specifically, the initial spacing between the anode plate 42 and the cathode rod 2 is set to 10 cm, and the target current density range is input; during operation, the array of high-precision current density monitoring sensors 3 distributed in a grid on the surface of the cathode rod 2 monitors the four-quadrant current density distribution in real time; when the electrolytic furnace 1 is electrolyzing, rare earth powder is added to the electrolytic furnace 1, and the graphite anode plate 42 reacts with oxygen to generate CO or CO2. The rare earth metal is precipitated on the cathode rod 2 and then falls into the crucible at the bottom of the electrolytic furnace 1. As the electrolysis time increases, the graphite anode plate 42 gradually becomes thinner, the distance between the anode plate 42 and the cathode rod 2 increases, the effective distance between the anode plate 42 and the cathode rod 2 dynamically shifts, the current density between the anode plate 42 and the cathode rod 2 decreases, the electrolyte resistance increases, and the current density monitoring sensor 3 detects the current density decrease in real time. When the deviation exceeds ±10% or the distance error is greater than ±0.5mm, a displacement instruction is generated based on the fuzzy PID algorithm (proportional-integral-differential parameter adaptive adjustment) to drive the target anode to move radially (forward / backward) at a speed of 1mm / s. The other three anodes are executed by detecting the current density. Compensating for displacement, so that the annular electric field strength formed by the four anodes is always in the optimal electrolysis state; the stepper motor adopts a communication protocol, and the multi-axis motion controller realizes four-axis synchronous control, ensuring the timely transmission of displacement instructions, and ultimately achieving the industrial effect of uniformity of electrolysis reaction current density, stable control of anode-cathode spacing, and extended anode life; the present invention can monitor current density in real time and dynamically adjust the anode position of the electrolytic furnace 1, which can effectively suppress the problem of pole spacing growth caused by anode consumption, thereby maintaining a stable electric field strength between the anode and cathode, improving the current density per unit area, and enhancing the reduction efficiency of metal ions. The present invention can improve current density uniformity and extend the life of the electrode 33. The annular current density monitoring sensor 3 monitors the current distribution on the surface of the cathode rod 2 in real time, and combines the fuzzy PID algorithm to dynamically adjust the position of the four anode plates 42, effectively improving electrolysis efficiency, avoiding anode ablation caused by local overload, extending the anode life, and lengthening the replacement cycle of the cathode rod 2.The system can enhance equipment adaptability and support complex operating conditions. It uses a high-temperature (>1000°C) embedded current density monitoring sensor 3 and a stainless steel ball screw 412, combined with a thermally insulated and sealed design, enabling continuous operation in highly corrosive molten salt environments. The system is resistant to fluctuations in high-temperature corrosive environments, reducing the failure rate. This invention can reduce manual intervention and improve the level of automation. It achieves coordinated motion control of four anodes through dynamic adjustment, with a response time of ≤100ms. This eliminates the need for manual adjustment of the electrode 33 position, reduces the number of operators, and meets the needs of industrial intelligent upgrades.

[0051] Second, see Figure 8 The present invention also provides a method for adjusting the anode position of a rare earth electrolytic furnace, comprising:

[0052] S101 monitors the current density between the electrolyte, cathode rod 2 and anode plate 42 in real time through the current density monitoring sensor 3, and feeds back to the controller in real time;

[0053] In this embodiment of the present invention, the electrolytic furnace's power supply is first turned on, the heating device is activated, and the temperature within the electrolytic cell 10 is raised to a preset operating temperature. This marks the starting point of the entire process, providing the necessary environmental conditions for the subsequent electrolysis process. The system then performs an initial self-test, which includes: checking that each sensor (particularly the current density monitoring sensor 33) is functioning properly; setting initial process parameters, such as the initial current, target current density, electrolyte composition, and initial interelectrode spacing; and initializing control algorithm parameters, such as the initial parameters and deviation thresholds for the fuzzy PID controller. This initialization ensures that the system is in a controllable initial state, ready for current application. Current is then applied to initiate electrolysis, closing the circuit and passing a preset direct current through the electrolytic cell 10. The electrolysis reaction begins (in rare earth electrolysis, the cathode rod 2 produces rare earth metals, and the anode plate 42 produces CO or CO2). Distributed current density monitoring sensors 3, located on the cathode rod 2, collect current density values ​​in real time across various regions of the cathode rod 2. This data is transmitted to the central controller. The resulting current density data serves as the basis for subsequent deviation detection and control. The present invention measures the current density by the electrolyte potential difference method and establishes a current-voltage relationship model using the oxygen ion migration characteristics of the solid electrolyte 32. The solid electrolyte 32 becomes an oxygen ion (O2-) conductor at high temperatures (>800°C). The oxygen vacancies in its crystal structure allow oxygen ions to migrate through a vacancy hopping mechanism, while the electronic conductivity is extremely low. This characteristic makes it an ideal "ion-selective transport medium". When the two ends of the solid electrolyte 32 are in contact with environments with different oxygen chemical potentials (i.e., between the surface of the cathode rod 2 and the electrolyte of the electrolytic furnace 1), the oxygen ions will migrate from the high chemical potential area to the low chemical potential area. According to the Nernst equation, this migration will form a potential difference (ΔE) on both sides of the solid electrolyte 32, and the calculation formula is:

[0054]

[0055] Where R is the gas constant, T is the temperature, and F is the Faraday constant. is the oxygen partial pressure, ref is the reference end (i.e., the cathode surface environment), and sample is the sample end (i.e., the electrolyte environment of the electrolytic furnace 1 to be tested).

[0056] During the electrolysis process, the current density j on the cathode surface is directly related to the oxygen ion migration rate. According to Faraday's law:

[0057]

[0058] Where z is the charge number of the oxygen ion (z=2), is the oxygen ion flux. It can be calculated by the ionic conductivity of the solid electrolyte 32 and the electric field strength (E = ΔV / d, d is the thickness of the solid electrolyte 32):

[0059]

[0060] Combining the above two equations, a linear model of j∝ΔV can be established.

[0061] Signal Transmission Solution: The high-temperature conductor of the current density monitoring sensor 3 utilizes molybdenum-coated platinum (Mo / Pt) wire, coated with a boron nitride insulation layer. This conductor withstands temperatures up to 1100°C and resists electrolyte corrosion. Signal processing converts the current signal into a digital quantity, which is then transmitted to the controller via the potential difference detected by the current density monitoring sensor 3, avoiding high-temperature electromagnetic interference.

[0062] S102: The controller calculates the anode target position according to the current density distribution, and controls the driving unit 41 to drive the anode plate 42 to move to the anode target position according to the calculated anode target position;

[0063] The specific steps include:

[0064] Perform RSI (Relative Standard Index, here refers to relative standard deviation) calculation. The controller calculates the distribution of the current density and compares it with the set target current density to obtain the deviation. A threshold is set to determine whether the deviation exceeds the threshold.

[0065] Calculate the Reaction Strength Index (RSI) using the following formula:

[0066]

[0067] Among them J avg is the current average current density in the anode area, d is the real-time inter-electrode distance, T is the electrolyte temperature, and V is the cell voltage;

[0068] Calculate the deviation value e(k) of the Reaction Strength Index RSI using the following formula:

[0069] e(k)=[(RSI,set)-(RSI,actual)]

[0070] Among them, RSI,set is the set value of RSI, and RSI,actual is the actual value of RSI;

[0071] Calculate the deviation value change rate Δe(k) using the following formula:

[0072] Δe(k)=e(k)-e(k-1)

[0073] The deviation and the rate of change of the deviation are used as inputs, and the fuzzy PID algorithm is used to output the anode displacement ΔS, where ΔS is adjusted according to the set threshold. If the current density in a certain anode area is higher than the set threshold, the control drive unit moves the anode plate outward to increase the spacing; if the current density in a certain anode area is lower than the set threshold, the control drive unit pushes the anode plate inward to reduce the spacing.

[0074] Regardless of whether the deviation exceeds the threshold, the system will use the fuzzy PID algorithm to calculate the anode displacement command. However, when the deviation exceeds the threshold, the adjustment range may be larger. The fuzzy PID algorithm combines the advantages of fuzzy control and traditional PID control:

[0075] PID control: linear control based on the proportion (P), integral (I), and differential (D) of the deviation.

[0076] Fuzzy control: takes the deviation and the rate of change of the deviation as input, performs reasoning through fuzzy rules, and outputs the adjustment amount of PID parameters or directly outputs the control amount.

[0077] The fuzzy PID algorithm converts the deviation into a specific control action, ensuring that the system achieves its goals quickly and stably. The control variable output by the fuzzy PID algorithm (i.e., the anode displacement command, displacement ΔS) is sent to the stepper motor driving the ball screw 412. The control command is converted into an execution instruction for the mechanical action.

[0078] Output variable: anode displacement ΔS, where ΔS is adjusted according to a set threshold value. If the current density in a certain anode area is higher than the set threshold value, the stepper motor driving the ball screw 412 is controlled to rotate forward or reverse, so that the anode plate 42 is moved outward to increase the spacing; if the current density in a certain anode area is lower than the set threshold value, the stepper motor driving the ball screw 412 is controlled to rotate reverse or forward, pushing the anode plate 42 inward to reduce the spacing. By changing the inter-electrode spacing, the current density distribution is affected and tends to the target value. After the above closed-loop control, the current density distribution of the electrolytic cell 10 is maintained within the target range. At this time, the electrolysis efficiency is high, the energy consumption is low, and the product quality is good, that is, the optimal electrolysis state is achieved. The goals of the entire control cycle are maintained through continuous monitoring and adjustment.

[0079] The present invention provides a method for adjusting the anode position of a rare earth electrolytic furnace. The current density monitoring sensor 3 is embedded in the cathode rod 2 in a grid-like distributed manner. The current density monitoring sensor 3 monitors the current density in real time and feeds back the deviation to the control system in real time for displacement compensation. Specifically, the initial spacing between the anode plate 42 and the cathode rod 2 is set to 10 cm, and the target current density range is input; during operation, the array of high-precision current density monitoring sensors 3 distributed in a grid on the surface of the cathode rod 2 monitors the four-quadrant current density distribution in real time; when the electrolytic furnace 1 is electrolyzing, rare earth powder is added to the electrolytic furnace 1, the graphite anode plate 42 reacts with oxygen to generate CO or CO2, and the rare earth metal is precipitated on the cathode rod 2 and then falls into the crucible at the bottom of the electrolytic furnace 1. As the electrolysis time increases, the graphite anode plate 42 gradually becomes thinner, the distance between the anode plate 42 and the cathode rod 2 increases, the effective distance between the anode plate 42 and the cathode rod 2 dynamically shifts, the current density between the anode plate 42 and the cathode rod 2 decreases, the electrolyte resistance increases, and the current density monitoring sensor 3 detects the current density decrease in real time. When the deviation exceeds ±10% or the distance error is greater than ±0.5mm, a displacement instruction is generated based on the fuzzy PID algorithm (proportional-integral-differential parameter adaptive adjustment) to drive the target anode to move radially (forward / backward) at a speed of 1mm / s. The other three anodes are executed by detecting the current density. The displacement is compensated so that the annular electric field strength formed by the four anodes is always in the optimal electrolysis state; the stepping motor adopts a communication protocol, and the multi-axis motion controller realizes four-axis synchronous control to ensure the timely transmission of the displacement instruction, and finally realizes the industrial effect of uniformity of electrolysis reaction current density, stable control of anode-anode distance and extension of anode life; the present invention can monitor the current density in real time, dynamically adjust the anode position of the electrolytic furnace 1, and can effectively suppress the problem of pole distance growth caused by anode consumption, thereby maintaining a stable electric field strength between the anode and the cathode, improving the current density per unit area, and enhancing the reduction efficiency of metal ions.

[0080] The above disclosure is merely one or more preferred embodiments of the present application and is not intended to limit the scope of the present application. A person skilled in the art will understand that all or part of the processes of the above embodiments and equivalent changes made in accordance with the claims of the present application are still within the scope of the present application.

Claims

1. A rare earth electrolytic furnace anode position adjustment device, comprising an electrolytic furnace, characterized in that: Also includes working components; The working assembly includes a cathode rod, a plurality of current density monitoring sensors and a plurality of anode adjustment components; The cathode rod is arranged on the inside of the electrolytic furnace, and multiple current density monitoring sensors are respectively arranged on the surface of the cathode rod; multiple anode adjustment components are respectively located on the side of the electrolytic furnace, and the anode adjustment components include a driving unit and an anode plate. The driving unit is arranged on the outside of the electrolytic furnace, and the anode plate is arranged on the side of the driving unit close to the electrolytic furnace.

2. The anode position adjustment device for a rare earth electrolytic furnace according to claim 1, wherein: The drive unit includes a shell, a ball screw, a sleeve and a slide plate; the shell is arranged on the outside of the electrolytic furnace; the ball screw is arranged on the inside of the shell; the sleeve is arranged on the side of the ball screw, and the sleeve is slidably connected to the shell; the slide plate is fixedly connected to the sleeve, and is fixedly connected to the anode plate, and is located between the sleeve and the anode plate.

3. The anode position adjustment device for a rare earth electrolytic furnace according to claim 2, characterized in that: The drive unit further includes a motor mounting compartment and a flange; the motor mounting compartment is fixedly connected to the housing and is located on the side of the housing; the flange is fixedly connected to the motor mounting compartment and is located inside the motor mounting compartment.

4. The anode position adjustment device for a rare earth electrolytic furnace according to claim 3, wherein: The current density monitoring sensor includes a shell, a solid electrolyte, two electrodes, two connecting parts, two welding parts, a dielectric layer, a thermocouple and a fiber layer; the shell is arranged on the surface of the cathode rod; the solid electrolyte is arranged in the center of the shell; the two electrodes are arranged on both sides of the solid electrolyte and in contact with the solid electrolyte; the two connecting parts are respectively connected to the two electrodes and are respectively located at the bottom of the two electrodes; the two welding parts are respectively arranged at the bottom of the two connecting parts; the dielectric layer is arranged between the electrodes and the connecting parts; the thermocouple is arranged on one side of the dielectric layer; and the fiber layer is arranged inside the shell.

5. A method for adjusting the anode position of a rare earth electrolytic furnace, applied to the anode position adjustment device of a rare earth electrolytic furnace according to any one of claims 1 to 4, characterized in that: include: The current density between the electrolyte, cathode rod and anode plate is monitored in real time by the current density monitoring sensor, and the current density is fed back to the controller in real time; The controller calculates the anode target position according to the current density distribution, and controls the driving unit to drive the anode plate to move to the anode target position according to the calculated anode target position.

6. The anode position adjustment device for a rare earth electrolytic furnace according to claim 5, characterized in that: The controller calculates the anode target position according to the current density distribution, and controls the driving unit to drive the anode plate to move to the anode target position according to the calculated anode target position. The specific steps include: Perform RSI calculation to calculate the distribution of current current density and compare it with the set target current density to obtain the deviation. Set a threshold to determine whether the deviation exceeds the threshold. Calculate the Reaction Strength Index (RSI) using the following formula: Among them J avg is the current average current density in the anode area, d is the real-time inter-electrode distance, T is the electrolyte temperature, and V is the cell voltage; Calculate the deviation value e(k) of the Reaction Strength Index RSI using the following formula: e(k)=[(RSI,set)-(RSI,actual)] Among them, RSI,set is the set value of RSI, and RSI,actual is the actual value of RSI; Calculate the deviation value change rate Δe(k) using the following formula: Δe(k)=e(k)-e(k-1) The deviation and the rate of change of the deviation are used as inputs, and the fuzzy PID algorithm is used to output the anode displacement ΔS, where ΔS is adjusted according to the set threshold. If the current density in a certain anode area is higher than the set threshold, the control drive unit moves the anode plate outward to increase the spacing; if the current density in a certain anode area is lower than the set threshold, the control drive unit pushes the anode plate inward to reduce the spacing.

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