Rare earth mineral dry separation control system and method based on airflow classification

Abstract

The application provides a rare earth mineral dry separation control system and method based on airflow classification, relates to the technical field of mineral separation, and sends the crushed rare earth mineral raw material into a cyclone separation cavity; the airflow velocity deviation in the dry separation chamber outlet channel is controlled through a classification rotation speed instruction to obtain a particle enrichment index corresponding to the outlet channel, the classification separation strategy of the rare earth mineral particles in directional guide separation is determined according to the particle enrichment index; the auxiliary air curtain flow in the corresponding outlet channel is independently adjusted in combination with the motion state information, the separation adaptation degree of the rare earth mineral particles of different densities at the outlet is determined through the auxiliary air curtain flow; the rare earth mineral particles entering the fine separation chamber are adjusted for secondary air supply according to the classification separation strategy and the separation adaptation degree, and different grades of rare earth concentrates are obtained. The application can cooperatively control the classification separation process of the rare earth mineral particles under airflow classification, so as to improve the separation efficiency of the rare earth concentrates of different grades.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of mineral separation, more particularly, the present application relates to a rare earth mineral dry separation control system and method based on airflow classification. BACKGROUND

[0002] Mineral separation refers to the use of physical separation, physical and chemical separation, etc. Combined technology, through pretreatment processes such as crushing and grinding, the mineral raw materials are dissociated into single particles to eliminate the influence of particle size difference, and then through the core separation units such as airflow classification, magnetic separation, gravity separation or flotation, the physical and chemical differences such as mineral particle density, magnetism and surface properties are used to realize the preliminary separation of useful minerals and gangue, and the key operating parameters such as separation medium flow rate, magnetic field strength and reagent dosage are dynamically adjusted to strengthen the enrichment effect of target mineral particles, so as to obtain high-purity target mineral products, improve the comprehensive utilization rate of mineral resources, avoid resource waste and meet the separation and purification process of high-quality mineral raw materials required by industrial production.

[0003] However, in the existing rare earth mineral dry separation control based on airflow classification, there is a lack of real-time and accurate monitoring of the motion state of the particle group in the cyclone separation cavity, the classification speed regulation and the airflow velocity deviation control of the multi-outlet channel lack of coordinated linkage, the auxiliary air curtain flow regulation is not combined with the airflow distribution gradient and the particle motion characteristics to form targeted optimization, and the secondary air supply adjustment is not based on the classification and separation strategy and the separation adaptation degree to implement differentiated regulation and control, so that the airflow field parameters and the separation requirements of rare earth ore particles are difficult to dynamically match, resulting in insufficient enrichment purity of target rare earth particles and poor separation adaptation of particles with different densities, thereby causing the grade differentiation of rare earth concentrate to be not obvious. Therefore, how to cooperatively regulate the classification and separation process of rare earth mineral particles under airflow classification to improve the separation efficiency of different grade rare earth concentrates is a problem faced by the industry. SUMMARY

[0004] The present application provides a rare earth mineral dry separation control system and method based on airflow classification, which can cooperatively regulate the classification and separation process of rare earth mineral particles under airflow classification to improve the separation efficiency of different grade rare earth concentrates.

[0005] In a first aspect, the present application provides a rare earth mineral dry separation control method based on airflow classification, which comprises the following steps:

[0006] The crushed rare earth mineral raw materials are sent into the cyclone separation cavity, so that the rare earth ore particle group moves in the forced cyclone flow field, and the motion state information of the particle group in the cyclone separation cavity is monitored;

[0007] According to the motion state information, the classification rotational speed instruction of the rotating impeller in the airflow classification is cooperatively adjusted, the airflow velocity deviation in the multiple outlet channels of the dry separation chamber is controlled through the adjusted classification rotational speed instruction, the particle enrichment index of the rare earth mineral particles at the corresponding outlet channel is obtained, and then the classification separation strategy of the rare earth mineral particles in the directional guide separation is determined according to the corresponding particle enrichment index;

[0008] The airflow distribution gradient fed back in real time at the multiple outlet channels is obtained, the auxiliary air curtain flow in the corresponding outlet channel is independently adjusted according to all the airflow distribution gradients combined with the motion state information, and then the separation adaptation degree of the rare earth mineral particles of different densities at the outlet is determined through all the auxiliary air curtain flows.

[0009] According to the classification separation strategy and all the separation adaptation degrees, the secondary air supply adjustment of the rare earth mineral particles entering the fine separation chamber is performed, and the rare earth concentrate of different grades is obtained.

[0010] In the embodiment, the cyclone separation chamber is a classification processing cavity for accommodating the broken rare earth mineral raw materials, and a forced cyclone flow field is formed through structure and power input.

[0011] In the embodiment, the forced cyclone flow field refers to a vortex field formed in the cyclone separation chamber, which can cause the differential motion of the rare earth mineral particle groups due to the centrifugal force and the airflow drag.

[0012] In the embodiment, the cooperative adjustment of the classification rotational speed instruction of the rotating impeller in the airflow classification according to the motion state information specifically includes:

[0013] According to the motion state information, the separation motion characteristics of the particles in the airflow classification are determined;

[0014] According to the separation motion characteristics, the cooperative adjustment rotational speed parameter of the rotating impeller is determined;

[0015] According to the cooperative adjustment rotational speed parameter, the classification rotational speed instruction of the rotating impeller in the airflow classification is determined.

[0016] In the embodiment, the cooperative adjustment refers to the adjustment mode of the linkage adjustment of the rotating impeller rotational speed parameter based on the motion state information and the separation motion characteristics of the rare earth mineral particle groups, so that the impeller rotational speed is accurately matched with the particle layering demand in the airflow classification.

[0017] In the embodiment, the classification separation strategy of the rare earth mineral particles in the directional guide separation determined according to the corresponding particle enrichment index specifically includes:

[0018] According to the particle enrichment index, the current classification separation efficiency of each outlet channel is evaluated;

[0019] determine a separation matching degree of the rare earth mineral particles of different densities at the outlet based on the separation efficiency;

[0020] determine a separation matching degree of the rare earth mineral particles of different densities at the outlet based on the separation efficiency;

[0021] In this embodiment, the separation matching degree of the rare earth mineral particles of different densities at the outlet determined by all the auxiliary air curtain flows specifically includes:

[0022] evaluate the separation matching degree of the rare earth mineral particles of different densities at the outlet based on all the auxiliary air curtain flows;

[0023] determine the actual composition of the separation products at each outlet and the enrichment purity of the target density particles based on the corresponding separation matching degree;

[0024] adjust the adjustment strategy of each auxiliary air curtain flow based on the enrichment purity and the target purity, so as to determine the separation matching degree of the rare earth mineral particles of different densities at the outlet.

[0025] In this embodiment, the secondary air supply adjustment of the rare earth mineral particles entering the fine separation chamber is performed according to the separation strategy and all the separation matching degrees, so as to obtain rare earth concentrates of different grades, which specifically includes:

[0026] set the corresponding secondary air supply adjustment amount of the fine separation chamber according to the separation strategy and all the separation matching degrees;

[0027] supply air according to each secondary air supply adjustment amount, and simultaneously monitor the dynamic distribution of the particle groups in different flow channels in the fine separation chamber;

[0028] match the corresponding particle group dynamic distribution with the target grade distribution, and output the rare earth concentrates of different grades enriched in different outlets.

[0029] In this embodiment, the fine separation chamber refers to a chamber for secondary purification of the rare earth mineral particles preliminarily separated in the dry separation chamber.

[0030] In a second aspect, the application provides a rare earth mineral dry separation control system based on air flow classification, which is used to execute a rare earth mineral dry separation control method based on air flow classification. The separation control system comprises:

[0031] The collection module is used to send the crushed rare earth mineral raw materials into the cyclone separation chamber, so that the rare earth mineral particle groups move in the forced cyclone flow field, and the movement state information of the particle groups in the cyclone separation chamber is monitored.

[0032] The airflow grading module is used for coordinating adjustment of a grading rotating speed instruction of a rotating impeller during airflow grading according to the motion state information, controlling airflow velocity deviation in a plurality of outlet channels of the dry separation chamber through the adjusted grading rotating speed instruction, obtaining a particle enrichment index of the rare earth mineral particles at the corresponding outlet channels, and further determining a grading separation strategy of the rare earth mineral particles during directional export separation according to the corresponding particle enrichment index.

[0033] The air supply adjustment module is used for obtaining airflow distribution gradients fed back in real time at the plurality of outlet channels, independently adjusting auxiliary air curtain flow rates in the corresponding outlet channels according to all the airflow distribution gradients in combination with the motion state information, and further determining separation adaptation degrees of rare earth mineral particles of different densities at the outlets through all the auxiliary air curtain flow rates.

[0034] The separation adjustment module is used for performing secondary air supply adjustment on the rare earth mineral particles entering the fine separation chamber according to the grading separation strategy and all the separation adaptation degrees, and obtaining rare earth concentrates of different grades.

[0035] The technical scheme provided by the embodiment has the following beneficial effects:

[0036] The crushed rare earth mineral raw materials are sent into the cyclone separation chamber, so that the rare earth mineral particle groups move in a forced cyclone flow field, and motion state information of the particle groups in the cyclone separation chamber is monitored. The grading rotating speed instruction of the rotating impeller during airflow grading is coordinated and adjusted according to the motion state information, the airflow velocity deviation in the plurality of outlet channels of the dry separation chamber is controlled through the adjusted grading rotating speed instruction, the particle enrichment index of the rare earth mineral particles at the corresponding outlet channels is obtained, and further the grading separation strategy of the rare earth mineral particles during directional export separation is determined according to the corresponding particle enrichment index. Airflow distribution gradients fed back in real time at the plurality of outlet channels are obtained, the auxiliary air curtain flow rates in the corresponding outlet channels are independently adjusted according to all the airflow distribution gradients in combination with the motion state information, and further the separation adaptation degrees of rare earth mineral particles of different densities at the outlets are determined through all the auxiliary air curtain flow rates. The secondary air supply adjustment is performed on the rare earth mineral particles entering the fine separation chamber according to the grading separation strategy and all the separation adaptation degrees, and rare earth concentrates of different grades are obtained.

[0037] It can be seen that in the present application, the differential secondary air supply adjustment of the fine separation chamber can be realized, and the output quality and resource comprehensive utilization rate of different grades of rare earth concentrate can be improved. Among them, by sending the crushed rare earth mineral raw material into the cyclone separation chamber and forming a forced cyclone flow field, the rare earth mineral particle group generates a differential motion trajectory, and the particle group motion state information is comprehensively monitored, solving the problems of lack of real-time and accurate monitoring of particle motion state in the prior art, poor initial matching of airflow field and particle separation demand; the classification speed instruction of the rotating impeller is adjusted according to the particle group motion state information, the airflow velocity deviation of the multiple outlet channels of the dry separation chamber is controlled through the instruction, and then the particle enrichment index is obtained and the classification and separation strategy is determined, eliminating the problems of lack of linkage between classification speed regulation and airflow velocity deviation control and insufficient target particle enrichment purity; by obtaining the airflow distribution gradient of multiple outlet channels, the auxiliary air curtain flow of the corresponding channel is independently adjusted in combination with the particle group motion state information, and then the separation adaptability of particles of different densities is determined, and the problems of lack of pertinence of auxiliary air curtain flow adjustment and poor separation adaptability of particles of different densities in the prior art are optimized; the particles entering the fine separation chamber are adjusted by secondary air supply according to the classification and separation strategy and all separation adaptabilities, and finally different grades of rare earth concentrate are obtained, avoiding the problems of lack of differential regulation of secondary air supply and not obvious grade differentiation of rare earth concentrate, and realizing the accurate secondary classification and purification of rare earth mineral particles.

[0038] In summary, the technical scheme adopted by the present application can cooperatively regulate the classification and separation process of rare earth mineral particles under airflow classification to improve the separation efficiency of different grades of rare earth concentrate. BRIEF DESCRIPTION OF DRAWINGS

[0039] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments or prior art description will be briefly introduced. Obviously, the drawings in the following description are only the embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0040] Figure 1 is an exemplary flowchart of a rare earth mineral dry separation control method based on airflow classification according to the present application;

[0041] Figure 2 is a flowchart for determining a particle enrichment index according to the present application;

[0042] Figure 3 is a flowchart for determining an auxiliary air curtain flow according to the present application;

[0043] Figure 4A module structure diagram of a rare earth mineral dry separation control system based on airflow classification is provided according to the present application. DETAILED DESCRIPTION

[0044] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by a person of ordinary skill in the art without creative labor fall within the scope of protection of the present application.

[0045] The present application provides a rare earth mineral dry separation control system and method based on airflow classification. The core is to send the crushed rare earth mineral raw material into a cyclone separation chamber, make the rare earth mineral particle group move in a forced cyclone flow field, monitor the motion state information of the particle group in the cyclone separation chamber, adjust the classification speed instruction of the rotating impeller during airflow classification according to the motion state information, control the airflow velocity deviation in the multiple outlet channels of the dry separation chamber through the adjusted classification speed instruction, obtain the particle enrichment index of the rare earth mineral particles at the corresponding outlet channel, and then determine the classification separation strategy of the rare earth mineral particles during directional derivation separation according to the corresponding particle enrichment index. The airflow distribution gradient at the multiple outlet channels is obtained, the auxiliary air curtain flow of the corresponding outlet channel is independently adjusted according to all the airflow distribution gradients combined with the motion state information, and then the separation adaptation degree of rare earth mineral particles of different densities at the outlet is determined through all the auxiliary air curtain flows. The rare earth mineral particles entering the fine separation chamber are adjusted by secondary air supply according to the classification separation strategy and all the separation adaptation degrees, and rare earth concentrates of different grades are obtained.

[0046] Embodiment one, in order to better understand the above technical solutions, the above technical solutions will be described in detail below in combination with the drawings and specific embodiments of the specification. Referring to Figure 1 The figure is an exemplary flowchart of a rare earth mineral dry separation control method based on airflow classification according to the present application. The separation control method includes the following steps:

[0047] In step S1, the crushed rare earth mineral raw material is sent into a cyclone separation chamber, the rare earth mineral particle group moves in a forced cyclone flow field, and the motion state information of the particle group in the cyclone separation chamber is monitored.

[0048] In a specific implementation, a tangential inlet, a central rotating impeller and a conical cavity wall with a taper of 1:5 can be used to build a cyclone separation chamber. Rare earth mineral raw materials with a particle size of 0.074 mm to 2 mm after crushing are fed into the chamber along the tangential inlet at a speed of 10 m / s to 20 m / s by a screw feeder. A variable frequency motor is started to drive the central rotating impeller to rotate at a speed of 500 rpm to 1500 rpm. The tangential velocity, radial velocity and axial velocity of the forced cyclone flow field are 15 m / s to 35 m / s, 2 m / s to 8 m / s and 1 m / s to 5 m / s, respectively, formed by the shrinkage of the conical cavity wall. The rare earth mineral particle group makes stable cyclone motion with the airflow. A high-speed camera system with a frame rate of 1000 frames per second is installed in the middle and lower parts of the chamber to capture the overall motion trajectory of the particle group. Three laser Doppler velocimeters are uniformly arranged along the radial direction to measure the tangential, radial and axial velocities of the particles. Particle concentration sensors are installed at corresponding positions to monitor the particle concentration distribution at different radial positions. The measurement data are integrated to obtain the motion state information of the particle group. In other embodiments, other methods can be used to determine the motion state information, which is not limited here.

[0049] It should be noted that in this application, the cyclone separation chamber is a classification processing cavity for containing crushed rare earth mineral raw materials and forming a forced cyclone flow field through structure and power input. The forced cyclone flow field refers to a vortex field formed in the cyclone separation chamber, which can cause differential motion of the rare earth mineral particle group due to centrifugal force and airflow drag. The motion state information refers to a parameter set of the motion characteristics of the rare earth mineral particle group in the cyclone separation chamber.

[0050] In step S2, the classification speed instruction of the rotating impeller during airflow classification is adjusted according to the motion state information. The airflow velocity deviation in the multiple outlet channels of the dry separation chamber is controlled by the adjusted classification speed instruction to obtain the particle enrichment index of the rare earth mineral particles at the corresponding outlet channels. Then, the classification and separation strategy of the rare earth mineral particles during directional derivation separation is determined according to the corresponding particle enrichment index.

[0051] In this embodiment, the classification speed instruction of the rotating impeller during airflow classification can be adjusted according to the motion state information by the following steps:

[0052] The separation motion characteristics of the particles during airflow classification are determined according to the motion state information.

[0053] The coordinated adjustment speed parameter of the rotating impeller is determined according to the separation motion characteristics.

[0054] The classification speed instruction of the rotating impeller during airflow classification is determined according to the coordinated adjustment speed parameter.

[0055] In practice, firstly, the three sets of motion state information obtained from the cyclone separation chamber—the rotational angular velocity of the particle group, the radial displacement velocity of the particle group, and the particle concentration gradient—are input into the data processing module for normalization. During processing, the actual value of each parameter is divided by its preset maximum value to obtain a normalized value in the 0-1 range. Then, combined with the balance relationship between particle centrifugal force and airflow drag, two core indicators, the stratification trend coefficient and stratification uniformity, are calculated. By comparing the preset thresholds of the two indicators, it is determined whether the particles are currently in an effective stratification, insufficient stratification, or excessive stratification state, and finally, a complete separation motion characteristic is formed. Then, the separation motion characteristic is input into the speed adjustment parameter calculation module. If it is determined to be insufficient stratification, i.e., the stratification trend coefficient is lower than the preset threshold, a positive adjustment amount is calculated, and the adjustment amount is positively correlated with the difference in stratification trend coefficient. If it is determined to be excessive stratification, i.e., the stratification uniformity is lower than the preset threshold, a negative adjustment amount is calculated, and the adjustment amount is positively correlated with the difference in stratification uniformity. If it is determined to be effective stratification, the adjustment amount is 0. Finally, the adjustment direction and adjustment amount are integrated to form a coordinated adjustment speed parameter. Finally, the coordinated adjustment speed parameters are input to the command conversion module, and the current real-time speed of the rotating impeller is read. Then, the adjustment amount in the coordinated adjustment speed parameters is algebraically calculated with the current real-time speed to obtain the target speed. Subsequently, the target speed is converted into a pulse width modulation signal that can be recognized by the variable frequency motor. The frequency of the pulse width modulation signal is linearly positively correlated with the target speed, and finally, a graded speed command that can directly drive the variable frequency motor of the rotating impeller is generated.

[0056] It should be noted that, in this application, "coordinated regulation" refers to a method of adjusting the rotational speed parameters of the impeller in conjunction with the motion state information and separation motion characteristics of the rare earth ore particle group, so as to precisely match the impeller speed with the particle stratification requirements of airflow classification; "airflow classification" refers to the classification process in which rare earth ore particles are separated into layers according to density and particle size characteristics by utilizing the swirling airflow field generated by the rotating impeller and the difference between centrifugal force and airflow drag force; "separation motion characteristics" refers to the set of trends and capabilities of the rare earth ore particle group to achieve stratified motion according to density and particle size during the airflow classification process; "coordinated regulation speed parameters" represent quantitative indicators that guide the adjustment of the rotating impeller speed; and "classification speed command" refers to the control signal that directly drives the variable frequency motor of the rotating impeller.

[0057] Preferably, in this embodiment, the airflow velocity deviation in multiple outlet channels of the dry separation chamber is controlled by adjusting the staged rotation speed command to obtain the particle enrichment index of rare earth mineral particles at the corresponding outlet channel, with reference to... Figure 2 As shown in the figure, this is a schematic flowchart of the process for determining particle enrichment indices in some embodiments of this application. In this embodiment, the determination of particle enrichment indices can be achieved by the following steps:

[0058] In step S21, the target air flow velocity of each outlet channel in the dry separation chamber is determined according to the classified rotational speed instruction;

[0059] In step S22, the actual air flow velocity in each outlet channel is monitored and the air flow velocity deviation thereof from the target air flow velocity is determined;

[0060] In step S23, the actual distribution amount of rare earth mineral particles in each outlet channel is determined according to all the air flow velocity deviations;

[0061] In step S24, the particle enrichment index of rare earth mineral particles at the corresponding outlet channel is obtained by comparing the actual distribution amount with the expected distribution amount.

[0062] In specific implementation, first, the adjusted classified rotational speed instruction is input to the velocity target calculation module, the radial position parameters of each outlet channel of the dry separation chamber are retrieved, the basic air flow velocity at each channel is calculated based on the positive correlation model of the impeller rotational speed and the tangential velocity of the flow field, the basic velocity is corrected in combination with the preset angle correction coefficient of the channel guide vane to obtain the target air flow velocity of each outlet channel, wherein the rotational impeller speed determines the tangential velocity of the cyclone flow field, the radial position of the outlet channel and the angle of the guide vane jointly affect the actual air flow velocity of the channel, which conforms to the velocity distribution law of the cyclone fluid mechanics. Then, a thermal gas flow speed sensor is installed at the center position of each outlet channel, the sensor collects the air flow velocity data in the channel in real time at a frequency of 10 Hz and transmits the data to the data processing module; the target air flow velocity is retrieved, the real-time actual velocity of each channel is subtracted from the corresponding target velocity to obtain the air flow velocity deviation of each channel, and a positive deviation indicates that the actual velocity is too high and a negative deviation indicates that the actual velocity is too low. Then, the air flow velocity deviations of all outlet channels are input to the particle distribution calculation module, the module retrieves the preset deviation-distribution correlation model, the model converts the deviation value of each channel into a particle distribution correction coefficient based on the positive correlation between the air flow velocity and the particle drag force, combines the basic distribution proportion of each channel to obtain the corrected distribution proportion through multiplication operation, and finally multiplies the total particle mass to obtain the actual distribution amount of each channel, wherein the air flow velocity deviation changes the air flow drag force on the particles, thereby affecting the enrichment degree of the particles to the corresponding channel, and the drag force is positively correlated with the square of the air flow velocity. Finally, the actual distribution amount of each outlet channel and the preset expected distribution amount are input to the enrichment index calculation module, the module performs division operation on the actual distribution amount and the expected distribution amount of each channel to obtain the particle enrichment index of the channel; at the same time, the index threshold is set, and when the particle enrichment index is greater than 1, it indicates that the enrichment degree exceeds the expectation, and when the particle enrichment index is less than 1, it indicates that the expectation is not reached.

[0063] It should be noted that in the present application, the airflow velocity deviation refers to the difference between the actual airflow velocity of each outlet channel and the target airflow velocity; the target airflow velocity refers to the preset airflow velocity value of each outlet channel; the actual distribution amount refers to the real mass proportion of rare earth mineral particles in each outlet channel; the expected distribution amount refers to the preset mass proportion of particles in each outlet channel based on ideal airflow conditions; and the particle enrichment index refers to the ratio of the actual distribution amount to the expected distribution amount of each outlet channel.

[0064] In the present embodiment, the classification and separation strategy of the rare earth mineral particles in directional derivation separation can be achieved by the corresponding particle enrichment index using the following steps:

[0065] According to the particle enrichment index, the current classification and separation efficiency of each outlet channel is evaluated;

[0066] Based on the classification and separation efficiency, the airflow adjustment parameters and outlet opening parameters for directional derivation separation of the rare earth mineral particles are determined;

[0067] According to the airflow adjustment parameters and the outlet opening parameters, the classification and separation strategy of the rare earth mineral particles in directional derivation separation is determined.

[0068] In specific implementation, first, the particle enrichment index of each outlet channel is input into the efficiency evaluation module. The module first calls the preset target particle enrichment index threshold, and then compares the actual particle enrichment index of each channel with the target particle enrichment index threshold through division operation to obtain the classification and separation efficiency of the channel. Then, according to the efficiency value, the efficiency is divided into three levels: high efficiency, medium efficiency and low efficiency. The high efficiency level is that the efficiency value is not less than 1, the medium efficiency is 0.5 to 1, and the low efficiency is less than 0.5. Then, the classification and separation efficiency level is input into the parameter calculation module. For the high efficiency level channel, the airflow adjustment parameters and outlet opening parameters are set to the current values and remain unchanged. For the medium efficiency level channel, the positive adjustment amount of the airflow adjustment parameters and the small positive adjustment amount of the outlet opening parameters are calculated. For the low efficiency level channel, the large positive adjustment amount of the airflow adjustment parameters and the negative adjustment amount of the outlet opening parameters are calculated. The adjustment amount is positively correlated with the difference between the efficiency value and the corresponding level threshold. Finally, the airflow adjustment parameters and outlet opening parameters of each channel are output, wherein the airflow velocity directly affects the drag force on the particles, and the outlet opening directly affects the particle derivation rate. The two parameters are adjusted together to optimize the enrichment and derivation effect of the particles in the channel. Finally, the airflow adjustment parameters and outlet opening parameters of each outlet channel are input into the strategy generation module. The module first constructs a parameter-strategy association matrix, and then according to the matrix, the strategy for the high efficiency channel is executed as "maintaining the current airflow adjustment parameters and outlet opening parameters, and directly directing the particles to derive", the strategy for the medium efficiency channel is executed as "adjusting the airflow and opening according to the calculated parameters, and deriving the particles after optimization", and the strategy for the low efficiency channel is executed as "adjusting the parameters, and if the efficiency is still not reached, the particles are returned to the cyclone separation chamber for reclassification". Finally, the classification and separation strategy is integrated.

[0069] It should be noted that in this application, the directional derivation separation refers to the precise separation process of guiding rare earth mineral particles with different enrichment degrees to the corresponding outlet channel; the separation efficiency refers to the index for quantitatively evaluating the separation effect of each outlet channel on rare earth mineral particles; the airflow adjustment parameter refers to the quantitative value of adjusting the airflow velocity in the outlet channel of the dry separation chamber; the outlet opening parameter refers to the quantitative value of adjusting the opening degree of the outlet valve; and the separation strategy refers to the execution rule for guiding the directional derivation and separation of rare earth mineral particles in each outlet channel.

[0070] In step S3, the airflow distribution gradient fed back in real time at the plurality of outlet channels is obtained, the auxiliary air curtain flow in the corresponding outlet channel is independently adjusted according to all the airflow distribution gradients combined with the motion state information, and then the separation adaptation degree of rare earth mineral particles with different densities at the outlet is determined through all the auxiliary air curtain flows.

[0071] In specific implementation, the airflow distribution gradient fed back in real time at the plurality of outlet channels can be realized in the following manner, that is, a high-precision gas flow meter is installed at the middle segment of each outlet channel, and a same type total gas flow meter is installed on the total air inlet pipeline of the dry separation chamber, all the flow meters collect the airflow flow data at the position in real time at a high frequency of 10 Hz, the real-time airflow flow data of each outlet channel and the total airflow flow data are synchronously transmitted to the data processing module through a data transmission line; the module first performs filtering and noise reduction processing on the collected original flow data, and eliminates abnormal fluctuation data, then calculates the ratio of the real-time airflow flow of each outlet channel to the total airflow flow, and then divides the difference between the ratios obtained by two consecutive calculations by the time interval to obtain the real-time airflow distribution gradient of each outlet channel, which will not be described here.

[0072] It should be noted that in this application, the airflow distribution gradient refers to the time variation rate of the proportion of the real-time airflow flow of each outlet channel to the total airflow flow.

[0073] Preferably, in this embodiment, the auxiliary air curtain flow in the corresponding outlet channel is independently adjusted according to all the airflow distribution gradients combined with the motion state information, and reference is made to FIG. 4, which is a flowchart for determining the auxiliary air curtain flow in some embodiments of the application. The auxiliary air curtain flow in this embodiment can be realized in the following steps: Figure 3

[0074] In step S31, the initial flow reference of the auxiliary air curtain corresponding to each channel is determined according to the airflow distribution gradient of all the outlet channels;

[0075] In step S32, the real-time distribution state of rare earth mineral particles at each outlet channel during separation is determined according to the motion state information; ​

[0076] In step S33, according to the deviation of each real-time distribution state from the expected distribution state, the initial flow reference of each auxiliary air curtain is combined to determine the auxiliary air curtain flow correction amount required for the corresponding channel;

[0077] In step S34, according to all auxiliary air curtain flow correction amounts, the auxiliary air curtain control instructions for each outlet channel are independently controlled to obtain the auxiliary air curtain flow in each outlet channel after independent adjustment.

[0078] In specific implementation, first, the real-time airflow distribution gradient of all outlet channels is input to the reference calculation module. The radial position, nozzle model and other structural parameters of each channel are first retrieved, and then based on the positive correlation between the airflow distribution gradient and the air curtain supplement demand, a gradient-flow reference mapping table is set. For channels with negative gradient (airflow distribution ratio decreases), a higher initial reference is set in proportion to the absolute value of the gradient, and for channels with positive gradient (airflow distribution ratio increases), a lower initial reference is set. After correction combined with channel structural parameters, the initial flow reference of the auxiliary air curtain of each channel is output. Then, the particle group rotation angular velocity, radial displacement velocity, particle concentration gradient and other motion state information monitored by the cyclone separation chamber are input to the distribution state analysis module according to the channel correspondence. The module determines the state by calculating the particle distribution uniformity and aggregation coefficient: distribution uniformity = 1 - (standard deviation of concentration at each monitoring point / average concentration), aggregation coefficient = area proportion of high concentration area, combined with the values of the two, the real-time distribution state is divided into uniform distribution, mild aggregation and severe aggregation. Among them, the particle motion state directly determines the distribution characteristics: the rotation angular velocity affects the centrifugal force distribution, the radial displacement velocity affects the particle diffusion, and the concentration gradient reflects the distribution difference. Then, the threshold of the expected distribution state is first preset in the module (uniform distribution: U d ≥ 0.8, K a ≤ 0.1, the deviation ΔU d of the real-time distribution uniformity of each channel from the expected value and the deviation ΔK a of the aggregation coefficient from the expected value are calculated; then based on the correlation model of the deviation and the correction amount, the correction amount of the uniform distribution channel is 0, the correction amount of the mild aggregation channel is initial reference × k3 × ΔK a , and the correction amount of the severe aggregation channel is initial reference × k4 × (ΔU d + ΔK a), wherein k3, k4 are deviation correction coefficients, and finally the correction amount of the auxiliary air curtain flow of each channel is obtained. Finally, the correction amount of the auxiliary air curtain flow of each channel is input to the command generation and execution module. The module first superimposes the correction amount and the initial flow reference to obtain the target flow, and then converts the target flow into the opening command of the electromagnetic regulating valve through the flow-opening conversion model (opening = initial opening + correction amount x k5, k5 is the conversion coefficient), and then sends the control command to the independent electromagnetic regulating valve of each channel, while the actual flow is monitored in real time through the air curtain flow sensor and fed back to the module for fine tuning to ensure that the auxiliary air curtain flow of each channel reaches the target value, i.e. the auxiliary air curtain flow in each outlet channel after independent adjustment.

[0079] It should be noted that in the present application, the initial flow reference of the air curtain refers to the basic flow value of the auxiliary air curtain set based on the outlet channel air flow distribution gradient; the real-time distribution state refers to the dynamic state of the density distribution, aggregation degree and motion trajectory of rare earth mineral particles in each outlet channel; the expected distribution state refers to the standard state of defining the ideal distribution of rare earth mineral particles in the outlet channel; the auxiliary air curtain flow correction amount refers to the quantitative value of adjusting the initial flow reference; the auxiliary air curtain control command refers to the command of converting the flow correction amount into an electrical signal that can drive the air curtain actuator; and the auxiliary air curtain flow refers to the air flow rate from the outlet channel air curtain nozzle after independent adjustment.

[0080] In the present embodiment, the separation adaptation degree of rare earth mineral particles of different densities at the outlet can be achieved by the following steps:

[0081] According to all the auxiliary air curtain flows, the separation matching degree of different density characteristic rare earth mineral particles under the air flow conditions at each outlet is evaluated;

[0082] The actual composition of the separation product at each outlet is determined by the corresponding separation matching degree, and the enrichment purity of the target density particles is determined;

[0083] Based on the enrichment purity and the target purity, the adjustment strategy of each auxiliary air curtain flow is adjusted to determine the separation adaptation degree of rare earth mineral particles of different densities at the outlet.

[0084] In a specific implementation, first, the auxiliary air curtain flow of each outlet channel after independent adjustment is input into a matching degree evaluation module. The critical drag parameters of rare earth mineral particles of different densities are first retrieved, and then the actual air flow velocity and turbulence intensity at the outlet are derived through the air curtain flow. The matching degree calculation model is as follows: separation matching degree=(actual air flow provided drag / critical drag required by target density particles) x air flow stability coefficient. According to the calculation results, the matching degree is divided into high, medium and low three matching levels, and the high matching level indicates that the air flow condition is completely adapted to the separation of the corresponding density particles. Then, according to the separation matching degree level, an automatic sampling device is arranged at the end of each outlet channel to collect sorting product samples at regular intervals. The composition of the samples is detected by X-ray fluorescence spectroscopy, and the mass proportion (i.e. actual composition) of rare earth mineral particles of different densities is calculated through the calibration curve of spectral intensity and element content. Then, the mass proportion data of the target density particles is extracted as the enrichment purity of the target density particles. Finally, the target purity of particles of different densities is preset, and the deviation value of the enrichment purity and the target purity at each outlet is calculated. For the channels with positive deviation value exceeding the allowed range, the adjustment strategy is to slightly reduce the auxiliary air curtain flow. For the channels with negative deviation value, the auxiliary air curtain flow is increased in proportion to the absolute value of the deviation. The adjusted enrichment purity and the target purity are input into the matching degree calculation model, and the separation matching degree is calculated as the ratio of the adjusted enrichment purity to the target purity. Finally, the separation matching degree of particles of different densities at each outlet is output.

[0085] It should be noted that in this application, the separation matching degree refers to the degree of adaptation of the air flow condition at each outlet to the separation requirements of rare earth mineral particles of different densities; the enrichment purity refers to the proportion of the mass of target density rare earth mineral particles to the total mass of particles at each outlet; the adjustment strategy refers to the execution rule for adjusting the auxiliary air curtain flow based on the deviation between the enrichment purity and the target purity; and the separation matching degree refers to an index for quantifying the matching degree of rare earth mineral particles of different densities with the corresponding outlet air flow condition and air curtain parameters.

[0086] In step S4, the rare earth mineral particles entering the fine separation chamber are subjected to secondary air supply adjustment according to the classification and separation strategy and all separation matching degrees, to obtain rare earth concentrates of different grades.

[0087] In this embodiment, the rare earth mineral particles entering the fine separation chamber are subjected to secondary air supply adjustment according to the classification and separation strategy and all separation matching degrees, to obtain rare earth concentrates of different grades, which can be achieved by the following steps:

[0088] According to the classification and separation strategy and all separation matching degrees, the corresponding inlet differential secondary air supply adjustment amount of the fine separation chamber is set;

[0089] Air supply is performed according to each secondary air supply adjustment amount, and the dynamic distribution of particle groups in different flow channels in the fine separation chamber is monitored synchronously;

[0090] By matching the corresponding particle group dynamic distribution with the target grade distribution, the rare earth concentrate of different grades enriched in different outlets is output.

[0091] In specific implementation, first, the classification separation strategy and all separation adaptation data input secondary air supply parameter setting module, the upstream outlet channel information corresponding to each inlet of the fine separation chamber is called first, the strategy-adaptation-air supply correlation model is established, then the air supply speed adjustment amount and direction adjustment angle of each inlet are calculated according to the high, medium and low efficiency levels of the classification separation strategy and the separation adaptation value, the low adjustment amount is set for the high efficiency and high adaptation inlet, the high adjustment amount is set for the low efficiency and low adaptation inlet, and the differential secondary air supply adjustment amount is output, that is, the differential secondary air supply adjustment amount of the corresponding inlet of the fine separation chamber is obtained. Then, the secondary air supply adjustment amount is input into the air supply control module of the fine separation chamber, the module converts the adjustment amount into the speed instruction of the variable frequency fan of each inlet and the angle instruction of the airflow direction adjuster, and starts the fan and the adjuster to execute differential air supply; at the same time, a high-speed camera system and a particle concentration sensor are installed in each flow channel of the chamber, the high-speed camera captures the particle motion trajectory at 1000 frames per second, and the concentration sensor monitors the particle concentration in the flow channel in real time, and the data is transmitted to the processing module synchronously, and the particle group dynamic distribution parameters are calculated. Finally, the target grade distribution threshold of each grade rare earth concentrate is preset in the processing module, the real-time particle group dynamic distribution parameters are compared with the target threshold, the distribution matching degree is calculated, the matching degree ≥0.9 is determined as the corresponding flow channel of the first grade concentrate, 0.7-0.9 is the second grade, and 0.5-0.7 is the third grade; the module sends a start instruction to the outlet collecting device of the corresponding flow channel, and installs a rare earth oxide content detection device at the outlet synchronously to verify the grade of the concentrate in real time, and the particles that do not meet the standard are transported back to the cyclone separation chamber through the backflow pipeline for reclassification.

[0092] It should be noted that in this application, the fine separation chamber refers to a chamber for secondary purification of rare earth mineral particles after preliminary classification in the dry separation chamber; the secondary air supply adjustment refers to the operation of differentially adjusting the air supply speed and direction of each corresponding inlet of the fine separation chamber according to the classification separation strategy and the separation adaptation; the secondary air supply adjustment amount refers to the quantitative value of the differential adjustment of the air supply speed and direction of each inlet of the fine separation chamber; the particle group dynamic distribution refers to the dynamic collection of the real-time concentration, density distribution and motion trajectory of rare earth mineral particles in different flow channels of the fine separation chamber; the target grade distribution refers to the ideal distribution standard of each grade rare earth concentrate in the corresponding flow channel.

[0093] It can be seen that in the present application, the differential secondary air supply adjustment of the fine separation chamber can be realized, and the output quality and resource comprehensive utilization rate of different grades of rare earth concentrate can be improved. Through the forced rotational flow field formed by feeding the crushed rare earth mineral raw material into the cyclone separation chamber, the rare earth mineral particle group generates a differential motion trajectory, and the particle group motion state information is comprehensively monitored, solving the problems of lack of real-time and accurate monitoring of particle motion state in the prior art, poor initial matching of airflow field and particle separation demand, and the like. According to the particle group motion state information, the classification speed instruction of the rotating impeller is cooperatively adjusted, the airflow velocity deviation of the multiple outlet channels of the dry separation chamber is controlled through the instruction, and then the particle enrichment index is obtained and the classification separation strategy is determined, eliminating the problems of lack of linkage between classification speed adjustment and airflow velocity deviation control, and insufficient target particle enrichment purity. By obtaining the airflow distribution gradient of the multiple outlet channels, the auxiliary air curtain flow of the corresponding channel is independently adjusted in combination with the particle group motion state information, and then the separation adaptability of particles of different densities is determined, optimizing the problems of lack of pertinence of auxiliary air curtain flow adjustment in the prior art, poor separation adaptability of particles of different densities, and the like. According to the classification separation strategy and all separation adaptabilities, the particles entering the fine separation chamber are subjected to secondary air supply adjustment, and finally different grades of rare earth concentrate are obtained, avoiding the problems of lack of differential regulation of secondary air supply, and non-obvious grade differentiation of rare earth concentrate, and realizing the accurate secondary classification and purification of rare earth mineral particles.

[0094] In summary, the technical scheme adopted by the present application can cooperatively regulate the classification and separation process of rare earth mineral particles under airflow classification, so as to improve the separation efficiency of different grades of rare earth concentrate.

[0095] In the second embodiment, the present application provides a rare earth mineral dry separation control system based on airflow classification. As shown in Figure 4 The separation control system includes:

[0096] The collection module 100 is used for feeding the crushed rare earth mineral raw material into the cyclone separation chamber, making the rare earth mineral particle group move in the forced rotational flow field, and monitoring the motion state information of the particle group in the cyclone separation chamber.

[0097] The airflow classification module 200 is used for cooperatively adjusting the classification speed instruction of the rotating impeller during airflow classification according to the motion state information, controlling the airflow velocity deviation in the multiple outlet channels of the dry separation chamber through the adjusted classification speed instruction, obtaining the particle enrichment index of the rare earth mineral particles at the corresponding outlet channels, and then determining the classification separation strategy of the rare earth mineral particles during directional derivation separation according to the corresponding particle enrichment index.

[0098] The air supply adjustment module 300 is configured to obtain the air flow distribution gradient fed back in real time at the plurality of outlet channels, and independently adjust the flow of the auxiliary air curtain in the corresponding outlet channel according to all the air flow distribution gradients combined with the motion state information, so as to determine the separation adaptation degree of the rare earth mineral particles of different densities at the outlet through all the auxiliary air curtain flows.

[0099] The separation adjustment module 400 is configured to perform secondary air supply adjustment on the rare earth mineral particles entering the fine separation chamber according to the separation strategy and all the separation adaptation degrees, so as to obtain rare earth concentrates of different grades.

[0100] The present application is described with reference to flowcharts and / or block diagrams of the methods, devices (systems) and computer program products according to the embodiments of the present application. It should be understood that each flow and / or block in the flowcharts and / or block diagrams, and the combination of the flows and / or blocks in the flowcharts and / or block diagrams can be implemented by computer program instructions. These computer program instructions can be provided to the processor of a general-purpose computer, a special-purpose computer, an embedded processor or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device produce a device that implements the functions specified in the flowcharts and / or block diagrams. Figure 1 The device that implements the functions specified in one flow or multiple flows and / or one block or multiple blocks. Figure 1 The device that implements the functions specified in one flow or multiple flows and / or one block or multiple blocks.

[0101] Those skilled in the art can understand that all or part of the steps in the above-mentioned embodiments can be completed by programs instructing related hardware, and the programs can be stored in a computer readable storage medium, including a read-only memory (ROM), a random access memory (RAM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), a one-time programmable read-only memory (OTPROM), an electrically erasable programmable read-only memory (EEPROM), a compact disc read-only memory (CD-ROM) or other optical disk storage, a magnetic disk storage, a magnetic tape storage, or any other computer readable medium capable of carrying or storing data.

[0102] It is also to be noted that the terms "comprising", "including", and any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but can also include other elements not expressly listed or inherent to such process, method, article, or apparatus. An element proceeded by "comprises a... " does not, without further restriction, exclude the existence of additional elements of the process, method, article, or apparatus that comprises the element.

Claims

1. A rare earth mineral dry separation control method based on air flow fractionation, characterized by, The separation control method comprises the following steps: The broken rare earth mineral raw material is sent into the cyclone separation chamber, so that the rare earth mineral particle group moves in the forced cyclone flow field, and the movement state information of the particle group in the cyclone separation chamber is monitored; The three groups of movement state information of the particle group rotation angular velocity, the particle group radial displacement velocity and the particle concentration gradient monitored by the cyclone separation chamber are input into a data processing module for normalization processing; then, in combination with the balance relationship between the particle centrifugal force and the airflow drag force, two core indexes of stratification trend coefficient and stratification uniformity are calculated, by comparing the preset threshold values of the two indexes, it is determined whether the particles are currently in an effective stratification, insufficient stratification or excessive stratification state, and then the separation movement characteristics are obtained, the coordinated adjustment rotation speed parameter of the rotating impeller is determined according to the separation movement characteristics, the classification rotation speed instruction of the rotating impeller during airflow classification is determined according to the coordinated adjustment rotation speed parameter, the airflow velocity deviation in the multiple outlet channels of the dry separation chamber is controlled through the adjusted classification rotation speed instruction, the particle enrichment index of the rare earth mineral particles at the corresponding outlet channels is obtained, and then the current classification separation efficiency of each outlet channel is evaluated according to the particle enrichment index, the airflow adjustment parameter and the outlet opening parameter used for the directional separation and export of the rare earth mineral particles are determined based on the classification separation efficiency, and the classification separation strategy of the rare earth mineral particles during directional export separation is determined according to the airflow adjustment parameter and the outlet opening parameter; The airflow distribution gradient feedback at the multiple outlet channels is obtained, the auxiliary air curtain flow of the corresponding outlet channel is independently adjusted according to all the airflow distribution gradients and the movement state information, and then the separation matching degree of the airflow conditions at each outlet to the rare earth mineral particles with different density characteristics is evaluated according to all the auxiliary air curtain flows, the actual composition of the separation products at each outlet is determined through the corresponding separation matching degree, the enrichment purity of the target density particles is determined, the adjustment strategy of each auxiliary air curtain flow is adjusted based on the enrichment purity and the target purity, and thus the separation adaptation degree of the rare earth mineral particles with different densities at the outlet is determined. According to the classification separation strategy and all the separation adaptation degrees, the rare earth mineral particles entering the fine separation chamber are subjected to secondary air supply adjustment, and rare earth concentrates with different grades are obtained.

2. A dry separation control method of rare earth mineral based on airflow classification according to claim 1, characterized in that, The cyclone separation chamber is a classification processing chamber for accommodating broken rare earth mineral raw materials and forming a forced cyclone flow field through structure and power input.

3. A dry separation control method of rare earth mineral based on airflow classification according to claim 1, characterized in that, The forced cyclone flow field refers to a vortex field formed in the cyclone separation chamber, which can cause differential movement of the rare earth mineral particle group due to centrifugal force and airflow drag force.

4. A dry separation control method of rare earth mineral based on airflow classification according to claim 1, characterized in that, The coordinated adjustment refers to the adjustment of the rotation speed parameter of the rotating impeller based on the movement state information and the separation movement characteristics of the rare earth mineral particle group, so that the impeller rotation speed is accurately matched with the particle stratification demand of airflow classification.

5. A dry separation control method of rare earth mineral based on airflow classification according to claim 1, characterized in that, According to the classification separation strategy and all the separation adaptation degrees, the rare earth mineral particles entering the fine separation chamber are subjected to secondary air supply adjustment, and rare earth concentrates with different grades are obtained. Specifically, the following steps are included: The secondary air supply adjustment amount of the corresponding inlet of the fine separation chamber is set according to the classification separation strategy and all the separation adaptation degrees; According to each secondary air supply adjustment amount, air is supplied, and the dynamic distribution of the particle groups in different flow channels in the fine separation chamber is monitored synchronously; By matching the corresponding particle group dynamic distribution and the target grade distribution, different grades of rare earth concentrate enriched in different outlets are output.

6. A dry separation control method of rare earth mineral based on airflow classification according to claim 1, characterized in that, The fine separation chamber refers to a cavity for secondary purification of rare earth mineral particles after preliminary classification in the dry separation chamber.

7. A control system for dry separation of rare earth minerals based on air classification for performing a control method for dry separation of rare earth minerals based on air classification according to any one of claims 1 to 6, characterized in that The separation control system comprises: The collection module is used for sending the crushed rare earth mineral raw materials into the cyclone separation cavity, making the rare earth mineral particle groups move in the forced cyclone flow field, and monitoring the motion state information of the particle groups in the cyclone separation cavity; The airflow classification module is used for adjusting the classification speed instruction of the rotating impeller during airflow classification according to the motion state information, controlling the airflow velocity deviation in the multiple outlet channels of the dry separation chamber through the adjusted classification speed instruction, obtaining the particle enrichment index of the rare earth mineral particles at the corresponding outlet channels, and then determining the classification and separation strategy of the rare earth mineral particles during directional derivation separation according to the corresponding particle enrichment index; The air supply adjustment module is used for obtaining the airflow distribution gradient fed back in real time at the multiple outlet channels, independently adjusting the auxiliary air curtain flow in the corresponding outlet channels according to all the airflow distribution gradients combined with the motion state information, and then determining the separation adaptation degree of rare earth mineral particles of different densities at the outlet through all the auxiliary air curtain flows; The separation adjustment module is used for performing secondary air supply adjustment on the rare earth mineral particles entering the fine separation chamber according to the classification and separation strategy and all the separation adaptation degrees, and obtaining rare earth concentrate of different grades.

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