Method for judging separation performance of spiral chute based on regulation and control of ore cutter and multi-index coupling
By constructing a multi-dimensional performance index prediction model, the impact of ore cutter control on spiral chute separation performance is quantified, solving the problems of inaccuracy and reliance on experience in existing evaluation methods, and realizing quantitative evaluation and stable and efficient separation of spiral chute separation performance.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-01-28
- Publication Date
- 2026-03-27
AI Technical Summary
Existing methods for evaluating the separation performance of spiral chute cannot accurately measure the dynamic changes brought about by continuous adjustment of the cutter. Furthermore, the separation indicators are mutually restrictive and difficult to quantify due to reliance on human experience, making it impossible to maintain stable and efficient separation performance under different feeding conditions.
An evaluation method based on the control of the ore cutter and the coupling of multiple indicators was adopted. Through a multi-dimensional performance index prediction model, the impact of the ore cutter position change on the separation performance was quantified. Grade efficiency factor, recovery efficiency factor and stability coefficient were constructed, and a multi-dimensional performance index prediction model was established. The separation parameters were optimized by combining numerical simulation experiments.
This enables quantitative evaluation of the separation performance of spiral chute, avoids interference from ore feeding conditions, improves horizontal comparability and close integration with production needs, and ensures the stability and efficiency of the separation process.
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Abstract
Description
TECHNICAL FIELD
[0001] The present application belongs to the field of mineral processing, and relates to a spiral chute separation performance evaluation method based on regulation of a rejector and multi-index coupling. BACKGROUND
[0002] In the field of mineral processing, spiral chute, as a gravity separation equipment using a composite force field of centrifugal inertia force and gravity, is widely used in the separation process of hematite, ilmenite, cassiterite and various non-ferrous minerals due to its simple structure, convenient operation, low cost and no pollution. The separation of particles in the spiral chute is essentially a complex process of multi-factor coupling, and the final separation performance is usually measured by multiple technical and economic indicators, mainly including concentrate grade, recovery rate, tailings grade and enrichment ratio.
[0003] In the traditional evaluation method of spiral chute separation performance, multiple index linkage is usually followed. Specifically, by changing a parameter (such as feed concentration, feed amount or structural parameter) while keeping other conditions fixed, the numerical changes of two technical indicators, concentrate grade and recovery rate, are investigated and compared simultaneously to evaluate the separation performance.
[0004] With the deepening understanding of the separation process of spiral chute, researchers began to try to introduce more comprehensive evaluation indicators. For example, the separation efficiency indicator can reflect the enrichment degree of the target mineral and the removal effect of the gangue mineral at the same time, thereby providing a useful reference for the comprehensive characterization of the separation performance of the spiral chute.
[0005] The above methods constitute the main technical basis for evaluating the separation performance of the spiral chute and guiding parameter optimization.
[0006] The limitations of the existing evaluation methods for the separation performance of the spiral chute include: first, in the separation index correlation analysis, there is a certain constraint relationship between the separation indicators such as concentrate grade and recovery rate, showing a typical trade-off characteristic. Specifically, in order to improve the concentrate grade, the rejector needs to be adjusted inward, which usually results in the loss of part of the recovery rate; conversely, if high recovery rate is pursued, the concentrate grade may decrease. This mutual constraint between indicators makes the judgment of separation performance often rely on human experience, and it is difficult to form a quantifiable basis for judgment.
[0007] Secondly, although the composite indicators such as separation efficiency make up for the above shortcomings to some extent, such indicators are easily affected by the feed grade.
[0008] Finally, it needs to be pointed out that the optimal result obtained according to the existing evaluation method often only considers the influence of the local position of the cut-off device, ignores the dynamic change of the separation performance caused by the continuous adjustment of the cut-off device, and cannot accurately represent the separation process of the spiral chute. Excellent separation conditions not only perform outstandingly at a specific radial position of the cut-off device, but also maintain stable and efficient separation performance within an adjustment range. SUMMARY
[0009] In order to solve the above problems, the technical scheme adopted by the present application is: a spiral chute separation performance evaluation method based on cut-off device regulation and multi-index coupling, characterized by comprising the following steps:
[0010] Obtaining the structure parameters, feed conditions and operation parameters of the target spiral chute; When the position of the cut-off device changes continuously within the same section, for multiple target spiral chutes with different parabolic exponents, and under the condition that other structure parameters, feed conditions and operation parameters are the same, based on the multi-dimensional performance index prediction model, the multi-dimensional performance indexes of the multiple target spiral chutes are compared, and when the multi-dimensional performance index value of the target spiral chute is the maximum, it is judged that the separation performance of the spiral chute is the best; When the position of the cut-off device changes continuously within the same section, for the same target spiral chute, when any one of the operation parameters is different, the other operation parameters, structure parameters and feed conditions are the same, or when any one of the feed conditions is different, the other feed conditions, structure parameters and operation parameters are the same, based on the multi-dimensional performance index prediction model, the multiple multi-dimensional performance indexes are compared, and when the multi-dimensional performance index value of the target spiral chute under the same condition is the maximum, it is judged that the separation performance of the spiral chute is the best.
[0012] Further, the calculation formula of the multi-dimensional performance index prediction model is as follows:
[0013] In the above formula, PI is the multi-dimensional performance index; A is the grade efficiency factor; B is the recovery efficiency factor; S is the stability coefficient; and λ and μ are the weight coefficients of the grade efficiency factor and the recovery efficiency factor, respectively, and satisfy λ+μ=1.
[0014] Further, the grade efficiency factor A represents the actual grade output relative to the theoretical best value within the range of qualified concentrate output, and the calculation formula of the degree of achievement of the grade efficiency factor A is as follows: A=G eff / (100%×W eff ) Where: G effis the integral area of the grade-orepass radial position curve within the effective separation interval; W eff is the total width of the effective separation interval.
[0015] Further, the integral formula of the integral area of the grade-orepass radial position curve within the effective separation interval is:
[0016] wherein: is the effective grade threshold; is the effective separation interval; is the grade distribution curve of the concentrate grade with the orepass radial position.
[0017] Further, the recovery efficiency factor B represents the degree of achievement of the recovery rate relative to the theoretical maximum value within the qualified concentrate output range; the calculation formula of the recovery efficiency factor B is as follows: B=R eff / (100%×W eff ) In the above formula, R eff is the integral area of the recovery rate-orepass radial position curve within the effective separation interval; W eff is the total width of the effective separation interval.
[0018] Further, the integral formula of the integral area of the recovery rate-orepass radial position curve within the effective separation interval is:
[0019] wherein the effective grade threshold is βmin, and the effective separation interval is , represents the grade distribution curve of the recovery rate with the orepass radial position.
[0020] Further, the stability coefficient S quantifies the degree of stability of the separation process, and the calculation formula of the stability coefficient S is as follows: S=1 / (1+k×CV) wherein CV is the coefficient of variation of all grade measurement values within the effective separation interval, and the expression is as follows: CV=σG / μG In the above formula, k is the grade fluctuation penalty weight coefficient; σG is the standard deviation of the grade within the effective separation interval; and μG is the average value of the grade within the effective separation interval.
[0021] Further, the effective separation interval is based on the set effective grade threshold, and all measurement points with a grade value not lower than the threshold are screened from all orepass radial position control points, and the effective grade threshold is the lowest concentrate grade value.
[0022] Further, the construction process of the multi-dimensional performance index prediction model comprises: Based on the structural parameters of the target spiral chute, the feeding conditions and the operation parameters; A numerical calculation model consistent with the physical process of the motion and separation behavior of the slurry is constructed and run, and the motion and separation behavior of the slurry in the spiral chute are numerically simulated; Based on the results of the numerical simulation test, the data of the distributed particles at the end of the third circle of the spiral chute are extracted, and the corresponding concentrate grade and recovery rate under different radial positions of the ore cutter are calculated, and the deterministic correspondence between the radial position of the ore cutter and each separation index is established to construct the multi-dimensional performance index prediction model.
[0023] Further, the structural parameters of the target spiral chute include the outer radius R, the inner radius r, the pitch P, the lower inclined angle γ and the number of turns N; The feeding conditions include the mineral type, the valuable element grade, the particle size and the density; The operation parameters include the solid mass concentration and the inlet volume flow.
[0024] The spiral chute separation performance evaluation method based on the ore cutter regulation and multi-index coupling provided by the present application is a comprehensive evaluation method that can quantify and integrate the continuous sliding characteristics and robustness requirements of the ore cutter, effectively measure the separation capacity of the equipment and avoid the interference of the feeding conditions, and has great significance. The method aims to convert the multiple single indexes that restrict each other into a series of comparable and robust multi-dimensional correlation indexes, thereby providing a scientific basis for the evaluation of the separation performance of the spiral chute.
[0025] The trade-off contradiction between "grade-recovery" is effectively solved by constructing a multi-dimensional performance evaluation system. Secondly, the method takes the final concentrate product characteristics as the evaluation benchmark, so it is not affected by the fluctuation of the original grade of the feed, and significantly improves the horizontal comparability of data under different feeding conditions, separation processes and production periods. In addition, by introducing the concept of effective grade threshold, the evaluation range is limited to the concentrate cutting interval that meets the product quality requirements, ensuring close combination with actual production needs. At the same time, the radial regulation strategy of the ore cutter is adopted to systematically investigate the performance characteristics in the effective separation interval, and accurately select the appropriate operation parameter interval that maintains excellent performance. In summary, the evaluation method established by the present application realizes the quantitative evaluation of the separation performance of the spiral chute by regulating the ore cutter and coupling multiple indexes, and provides a scientific basis for the determination of the structure design or operation parameters of the spiral chute.
[0026] A spiral chute separation performance evaluation method based on the regulation of the ore cutter and the coupling of multiple indexes is established to realize the quantification and screening of the separation performance under different conditions. BRIEF DESCRIPTION OF DRAWINGS
[0027] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the accompanying drawings needed to be used in the embodiments or prior art description will be briefly introduced. Obviously, the accompanying drawings in the following description are only some embodiments of the present application, and all other drawings obtained by those of ordinary skill in the art without creative labor based on these drawings also belong to the protection scope of the present application.
[0028] Figure 1 is a flow chart of the method; Figure 2 is a grade effective integral area graph; wherein (a) is a grade effective integral area graph when the serial number is I; (b) is a grade effective integral area graph when the serial number is II; (c) is a grade effective integral area graph when the serial number is III; (d) is a grade effective integral area graph when the serial number is IV; (e) is a grade effective integral area graph when the serial number is V; Figure 3 is a recovery rate effective integral area graph; wherein (a) is a recovery rate effective integral area graph when the serial number is I; (b) is a recovery rate effective integral area graph when the serial number is II; (c) is a recovery rate effective integral area graph when the serial number is III; (d) is a recovery rate effective integral area graph when the serial number is IV; (e) is a recovery rate effective integral area graph when the serial number is V. DETAILED DESCRIPTION
[0029] It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict, and the present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.
[0030] In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the accompanying drawings of the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, but not all the embodiments. The description of the at least one exemplary embodiment is actually only illustrative, but not as any limitation on the present application and its application or use. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative labor also belong to the protection scope of the present application.
[0031] A spiral chute separation performance evaluation method based on a cutting machine regulation and multi-index coupling: comprising the following steps: S1: obtaining the structure parameters, ore feeding conditions and operation parameters of a target spiral chute; S2: When the position of the cut-off device is constantly changing in the same section, the parabolic index of the multiple target spiral chute is different, other structural parameters, feeding conditions and operating parameters are the same, and the multi-dimensional performance index prediction model is used to compare the multi-dimensional performance indexes of the multiple target spiral chutes. When the multi-dimensional performance index value of the target spiral chute is the largest, it is determined that the separation performance of the spiral chute is the best; The cross-section curve function is composed of the lower inclination angle and the parabolic index in the structural parameters, S3: When the position of the cut-off device is constantly changing in the same section, for the same target spiral chute, when any one of the operating parameters is different, other operating parameters, structural parameters and feeding conditions are the same, or when any one of the feeding conditions is different, other feeding conditions, structural parameters and operating parameters are the same, the multi-dimensional performance indexes are compared based on the multi-dimensional performance index prediction model. When the multi-dimensional performance index value of the target spiral chute under the same condition is the largest, it is determined that the separation performance of the spiral chute is the best.
[0032] After the step S1 is executed, S2 / S3 is executed in parallel; Further, the calculation formula of the multi-dimensional performance index prediction model is as follows:
[0033] In the above formula, PI is the multi-dimensional performance index; A is the grade efficiency factor; B is the recovery efficiency factor; S is the stability coefficient; and λ and μ are the weight coefficients of the grade efficiency factor and the recovery efficiency factor, respectively, and satisfy λ+μ=1.
[0034] Further, the grade efficiency factor A represents the actual grade output relative to the theoretical best value within the range of qualified concentrate output. The calculation formula of the degree of achievement of the grade efficiency factor A is as follows: A=G eff / (100%×W eff ) Where: G eff is the integral area of the grade-cut-off device radial position curve in the effective separation interval; and W eff is the total width of the effective separation interval.
[0035] The radial position of the cut-off device is the distance between the cut-off device baffle and the radius of the spiral groove. The grade refers to the percentage content of useful mineral components in the concentrate product. The higher the grade, the purer the product, and the value is usually higher; Grade - Radial position of the cutter: This refers to the fact that by adjusting the radial position of the cutter at the bottom of the spiral chute, the width of the collected ore band can be directly changed. Adjusting it inward will only collect the innermost high-purity heavy minerals, resulting in a high grade but a small quantity. Adjusting it outward will collect a wider ore band, recovering more heavy minerals, but also introducing more impurities, leading to a decrease in grade.
[0036] Grade-cutter radial position curve: This refers to the curve formed by gradually moving the cutter from the innermost edge of the spiral groove to the outermost edge, and obtaining the concentrate grade at each fixed position. The corresponding concentrate grade and the radial position of the cutter are then plotted on a coordinate graph, which can intuitively show the changing pattern of the two.
[0037] The integral formula for the integral area of the grade-cutter radial position curve within the effective separation interval is:
[0038] in: The effective grade threshold; For effective separation intervals; The curve formed by grade and radial position of the cutter; Furthermore: the recovery efficiency factor B characterizes the degree to which the recovery rate is achieved relative to the theoretical maximum value within the range of qualified concentrate output; the calculation formula for the recovery efficiency factor B is as follows: B=R eff / (100% × W) eff ) In the above formula, R eff W is the integral area of the recovery rate-cutter radial position curve within the effective separation range. eff To effectively separate the total width of the interval.
[0039] Recovery rate is a measure of the efficiency of a sorting process in extracting valuable minerals from the ore in terms of quantity. The formula for calculating the recovery rate is: Recovery rate = (Total weight of useful minerals in the concentrate / Total weight of useful minerals in the raw ore) × 100% By adjusting the cutter further outward, the width of the cut-off ore flow increases, and the total amount of useful minerals entering the concentrate product also increases, thus increasing the recovery rate (amount of useful minerals in the concentrate / amount of useful minerals in the raw ore). Recovery rate-cutter radial position curve: This refers to the curve formed by gradually moving the cutter from the innermost edge of the spiral groove to the outermost edge, and obtaining the recovery rate at each fixed position. The corresponding recovery rate and the radial position of the cutter are then plotted on a coordinate graph, creating a curve that visually shows the changing pattern of the two.
[0040] The integral formula of the recovery rate-radial position of the crosscutting device curve is the integral area of the effective separation interval.
[0041] The effective grade threshold is β min , and the effective separation interval is , : the curve formed by the recovery rate-radial position of the crosscutting device; Further, the stability coefficient S quantifies the degree of stability of the separation process, and the calculation formula of the stability coefficient S is as follows: S = 1 / (1 + k × CV) Wherein, CV is the coefficient of variation of all grade measurements in the effective separation interval, and its expression is as follows: CV = σG / μG In the above formula, k is the grade fluctuation penalty weight coefficient; σG is the standard deviation of the grade in the effective separation interval; and μG is the average value of the grade in the effective separation interval.
[0042] Further, the effective separation interval is based on the set effective grade threshold, and from all radial position control points of the crosscutting device, all measurement points with a grade value not lower than the threshold are screened out.
[0043] Further, the effective grade threshold is the minimum concentrate grade value.
[0044] Further, the construction process of the multi-dimensional performance index prediction model includes: Based on the structural parameters of the target spiral chute, the ore feeding conditions and the operation parameters; A numerical calculation model consistent with the physical process of the motion and separation behavior of the ore pulp is constructed and run, and the motion and separation behavior of the ore pulp in the spiral chute are numerically simulated; Based on the results of the numerical simulation test, the data of the distributed particles at the end of the third circle of the spiral chute are extracted, and the corresponding concentrate grade and recovery rate under different radial positions of the crosscutting device are calculated, and the deterministic correspondence between the radial position of the crosscutting device and each separation index is established to construct the multi-dimensional performance index prediction model.
[0045] At the end of the third circle of the spiral chute, the heavy minerals and light minerals have formed a stable and clear separation zone along the width of the chute (the inner edge is rich in heavy minerals, and the outer edge is rich in light minerals), at which time the grade and recovery rate reach a dynamic balance and basically do not change significantly with the number of turns.
[0046] The numerical calculation model includes a turbulent flow model, a clear water phase model and a multiphase flow model. Further, the turbulence model is a RNG k-ε turbulence model based on a renormalization group (RNG), differential transport equations of turbulent kinetic energy and turbulent dissipation rate of the RNG k-ε turbulence model are as shown in formulas (1) and (2); the clear water phase model is a VOF model, control equations of the VOF multiphase flow model are as shown in formulas (3) and (4), and the multiphase flow phase model is an Eulerian multi-fluid VOF multiphase flow model considering Bagnold effect; (1) (2) In the formulas, G k represents a turbulent kinetic energy generation term; is an effective viscosity (sum of molecular viscosity and turbulent viscosity) kg / (m·s); is an additional term in the turbulent kinetic energy dissipation rate equation; k is turbulent kinetic energy, J / kg; is turbulent kinetic energy dissipation rate, W / kg; , is a coefficient in the model.
[0047] (3) (4) In the formulas, is a volume fraction of a certain phase, when q =1, it is a water phase, and when q =2, it is a gas phase; t is time, s; (or ) is a coordinate component; (or ) is a component of velocity in the i (or j ) direction, m / s; is gravitational acceleration, m / s 2 ; and are average density and viscosity of the fluid respectively, kg / m 3 , kg / (m·s).
[0048] Further, the RNG k-ε turbulence model and the VOF multiphase flow model are adopted to obtain a stable gas-liquid two-phase flow field; Further, the particle phase is added to the stable gas-liquid two-phase flow field, and the RNG k-ε turbulence model and the Eulerian Multi-fluid VOF multiphase flow model are used to investigate the gas-liquid-solid multiphase flow field. Further, the calculation of the corresponding concentrate grade and recovery rate at different radial positions of the ore cutting device is as follows: The radial position L of the ore cutting device is a radial division point, and the radial position L of the ore cutting device can slide from the inner radius r position to the outer radius R position, i.e. r≤L≤R, and all particles satisfying r≤L are screened out, and this part of the particle set represents the concentrate obtained at the position of the ore cutting device,
[0049]
[0050] Embodiment 1: A spiral chute separation performance evaluation method based on ore cutting device regulation and multi-index coupling, the flowchart is as shown in Figure 1 The method comprises the following steps: S1, determining the structure parameters and ore feeding conditions of a plurality of target spiral chutes, and designing the condition parameters to be evaluated; The structure parameters of the target spiral chute include outer radius R, inner radius r, pitch P, lower inclination angle γ, and number of turns N; Further, the outer radius R=150 mm, the inner radius r=30 mm, the pitch P=240 mm, the lower inclination angle γ=9°, and the number of turns N=3; The ore feeding conditions of the target spiral chute include mineral types, valuable element grade, particle size, and density; The operating parameters include solid mass concentration and inlet volume flow rate; The test conditions of the method are as follows: when the ore cutting device changes the position in the same cross section, the cross section curve functions of the plurality of target spiral chutes are different, and the other structure parameters, ore feeding conditions, and operating parameters are the same; Further, the mineral types are useful mineral hematite and gangue mineral quartz particles, the ore feeding iron grade is 45.59%, the particle sizes of the useful mineral hematite and the gangue mineral quartz particles are set to 90 μm and 38 μm respectively, the densities of the useful mineral hematite and the gangue mineral quartz particles are set to 4950 kg / m3 and 2650 kg / m3 respectively, the solid mass concentration is 20%, and the inlet volume flow rate is 12 L / min; The condition parameters to be evaluated are the cross section curve functions, and the cross section curve functions are shown in Table 1.
[0051] Table 1 Cross section curve functions
[0052] S2, according to the determined target spiral chute structure parameters and ore feeding conditions, constructing a numerical calculation model conforming to the physical process of ore pulp movement and separation behavior, and performing numerical simulation test on the movement and separation behavior of particles in the spiral chute; The numerical simulation test comprises solving a gas-liquid two-phase flow field, and introducing a particle phase on the basis to simulate gas-liquid-solid three-phase flow.
[0053] S3, based on the numerical simulation results, extracting the distribution data of particles at the end of the third circle of the spiral chute, and calculating the corresponding concentrate grade and recovery rate at different radial positions of the ore cutter, establishing a deterministic correspondence between the radial position of the ore cutter and each separation index, providing basic data for subsequent construction of a multi-dimensional performance index prediction model, and constructing the multi-dimensional performance index prediction model; The calculation formula of the multi-dimensional performance index prediction model is as follows: PI=(A^λ·B^μ)·S In the above formula, PI is the multi-dimensional performance index; A is the grade performance factor; B is the recovery rate performance factor; S is the stability coefficient; λ and μ are weight coefficients of the grade performance factor and the recovery rate performance factor respectively, and satisfy λ+μ=1.
[0054] Further, in the present embodiment, λ=0.5, μ=0.5, indicating that the grade and the recovery rate have equal important positions in the comprehensive evaluation; Further, the grade performance factor A represents the degree of actual grade output relative to the theoretical optimal value within the range of qualified concentrate output, and its calculation formula is as follows: A=Geff / (100%×Weff) In the above formula, Geff is the integral area of the grade-ore cutter radial position curve within the effective separation interval; Weff is the total width of the effective separation interval.
[0055] Further, the recovery rate performance factor B represents the degree of recovery rate relative to the theoretical maximum value within the range of qualified concentrate output, and its calculation formula is as follows: B=Reff / (100%×Weff) In the above formula, Reff is the integral area of the recovery rate-ore cutter radial position curve within the effective separation interval; Weff is the total width of the effective separation interval.
[0056] Further, the effective separation interval is based on the set effective grade threshold, and all measurement points with a grade value not lower than the threshold are selected from all ore cutter radial position control points. The continuous or discontinuous radial position range formed by these points is uniformly defined as the effective separation interval, and the total width is denoted as Weff; Further, the effective grade threshold is the minimum concentrate grade value meeting the product scheme quality specification; Further, in the embodiment, the effective grade threshold is set as 63%. Based on the threshold, the grade effective integral area and the recovery rate effective integral area under each section curve function are obtained, and the results are shown in Figs. 4 and 5, respectively. Figure 2 and Figure 3 .
[0057] Figure 2 Fig. 4 is a diagram of grade effective integral area; wherein (a) is the diagram of grade effective integral area when the serial number is I; (b) is the diagram of grade effective integral area when the serial number is II; (c) is the diagram of grade effective integral area when the serial number is III; (d) is the diagram of grade effective integral area when the serial number is IV; (e) is the diagram of grade effective integral area when the serial number is V; Figure 3 Fig. 5 is a diagram of recovery rate effective integral area; wherein (a) is the diagram of recovery rate effective integral area when the serial number is I; (b) is the diagram of recovery rate effective integral area when the serial number is II; (c) is the diagram of recovery rate effective integral area when the serial number is III; (d) is the diagram of recovery rate effective integral area when the serial number is IV; (e) is the diagram of recovery rate effective integral area when the serial number is V.
[0058] The values of the grade performance factor A and the recovery rate performance factor B under each section curve function calculated based on the integral area are shown in Table 2.
[0059] Table 2 Grade performance factor A and recovery rate performance factor B corresponding to different section curve functions
[0060] Further, the stability coefficient S quantifies the stability degree of the separation process, so that the model not only pursues high average performance, but also pursues low performance fluctuation. The closer the value is to 1, the more stable the separation process is. The calculation formula is as follows: S = 1 / (1+kxCV) wherein, CV is the coefficient of variation of all grade measurement values in the effective separation interval, and the expression is as follows: CV = σ G / μ G In the above formula, k is the grade fluctuation penalty weight coefficient; σ G is the standard deviation of the grade in the effective separation interval; μ G is the average value of the grade in the effective separation interval.
[0061] Further, in the embodiment, the grade fluctuation penalty weight coefficient k is set as 2. Based on the grade data in the effective separation interval, the standard deviation σ G and the average value μG and the coefficient of variation CV derived therefrom, and finally the stability coefficient S is calculated, and all numerical results are summarized in Table 3.
[0062] Table 3 Stability-related parameters of different cross-sectional curve functions
[0063] S4, for the target spiral chute under different conditions, based on the multi-dimensional performance index prediction model, the multi-dimensional performance index is calculated, and the optimal condition parameter is determined; Further, based on the multi-dimensional performance index prediction model, the PI values under each cross-sectional curve function are calculated and compared, and the one corresponding to the maximum PI value is the optimal cross-sectional curve function. The comparison results are shown in Table 4.
[0064] Table 4 Stability-related parameters of different cross-sectional curve functions
[0065] S5: Compare the multi-dimensional performance index values of the target spiral chute under different conditions, and when the multi-dimensional performance index value of the target spiral chute is the maximum, it is judged that the separation performance of the spiral chute is the best; As can be seen from Table 4, when the serial number is IV, the multi-dimensional performance index PI value is the maximum, which indicates that the spiral chute under this condition is more conducive to the separation of hematite and quartz.
[0066] Example 2: S1: Obtain the structure parameters, feed conditions and operation parameters of the target spiral chute; when the cross cutter changes position in the same cross section, the test conditions of the present application are: for the same operation parameters, different values of the same target spiral chute, the same structure parameters, the same feed conditions and the same operation parameters; that is, the solid mass concentration or the inlet volume flow rate condition is under the change of different values; S2: Build and run a numerical calculation model consistent with the physical process of the movement and separation behavior of the ore slurry, and perform numerical simulation test on the movement and separation behavior of the ore slurry in the spiral chute; S3: Based on the numerical simulation test results, the data of the distribution particles at the end of the third circle of the spiral chute are extracted, and the corresponding concentrate grade and recovery rate under different cross cutter radial positions are calculated, and a deterministic correspondence between the cross cutter radial position and each separation index is established to build a multi-dimensional performance index prediction model; S4: Based on the multi-dimensional performance index prediction model, the multi-dimensional performance index of the same target spiral chute under the same operation parameters and different values is calculated; S5: comparing the multi-dimensional performance indexes of the same target spiral chute under the same operation parameter and different values, and determining that the spiral chute has the best separation performance when the multi-dimensional performance index value of the target spiral chute is the largest.
[0067] Embodiment 3: S1: obtaining the structure parameters, ore feeding conditions and operation parameters of a target spiral chute; when the position of the ore cutter changes in the same section, the test conditions of the present application are as follows: for the same ore feeding conditions of the same target spiral chute, different values, the same structure parameters and operation parameters, and the same other ore feeding conditions; that is, any one of the mineral type, valuable element grade, particle size and density changes under different values; S2: constructing and running a numerical calculation model corresponding to the physical process of the motion and separation behavior of the ore pulp, and performing numerical simulation test on the motion and separation behavior of the ore pulp in the spiral chute; S3: based on the numerical simulation test results, extracting the data of the distributed particles at the end of the third circle of the spiral chute, and calculating the concentrate grade and recovery rate corresponding to the radial position of the ore cutter, establishing a deterministic correspondence between the radial position of the ore cutter and each separation index, and constructing a multi-dimensional performance index prediction model; S4: based on the multi-dimensional performance index prediction model, calculating the multi-dimensional performance indexes of the same target spiral chute under the same operation parameter and different values; S5: comparing the multi-dimensional performance indexes of the same target spiral chute under the same operation parameter and different values, and determining that the spiral chute has the best separation performance when the multi-dimensional performance index value of the target spiral chute is the largest.
[0068] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present application, and not to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that: it can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement for part or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application.
Claims
1. A method for evaluating the separation performance of a spiral chute based on the coupling of ore cutter control and multiple indicators, characterized in that: Includes the following steps: Obtain the structural parameters, feeding conditions, and operating parameters of the target spiral chute; When the position of the cutter changes continuously within the same cross section, the parabolic exponents of multiple target spiral chutes are different. Under the condition that other structural parameters, feeding conditions and operating parameters are the same, the multidimensional performance indexes of multiple target spiral chutes are compared based on the multidimensional performance index prediction model. When the multidimensional performance index value of the target spiral chutes is the largest, it is judged that the spiral chutes have the best separation performance. When the position of the cutter changes continuously within the same cross section, for the same target spiral chute, under the conditions that any one of the operating parameters is different while the other operating parameters, structural parameters, and feeding conditions are the same, or under the conditions that any one of the other feeding conditions is different while the other feeding conditions, structural parameters, and operating parameters are the same, based on the multidimensional performance index prediction model, multiple multidimensional performance indices are compared. When the multidimensional performance index value of the target spiral chute is the largest under the same conditions, it is judged that the spiral chute has the best separation performance.
2. The method for evaluating the separation performance of a spiral chute based on the control of a ore cutter and the coupling of multiple indicators as described in claim 1, characterized in that: The calculation formula for the multidimensional performance index prediction model is as follows: In the above formula, PI is the multidimensional performance index; A is the grade efficiency factor; B is the recovery efficiency factor; S is the stability coefficient; λ and μ are the weighting coefficients of the grade efficiency factor and the recovery efficiency factor, respectively, and satisfy λ+μ=1.
3. The method for evaluating the separation performance of a spiral chute based on the control of a cutter and the coupling of multiple indicators as described in claim 1, characterized in that: The grade efficiency factor A represents the actual grade output relative to the theoretical optimal value within the range of producing qualified concentrate. The formula for calculating the degree of achievement of the grade efficiency factor A is as follows: A=G eff / (100%×W eff ) Among them: G eff W is the integral area of the grade-cutter radial position curve within the effective separation interval. eff To effectively separate the total width of the interval.
4. The method for evaluating the separation performance of a spiral chute based on the control of a cutter and the coupling of multiple indicators as described in claim 3, characterized in that: The integral formula for the integral area of the grade-cutter radial position curve within the effective separation interval is: in: The effective grade threshold; For effective separation intervals; This is a distribution curve showing the change in concentrate grade with the radial position of the cutter.
5. The method for evaluating the separation performance of a spiral chute based on the control of a cutter and the coupling of multiple indicators as described in claim 1, characterized in that: The recovery efficiency factor B characterizes the degree to which the recovery rate is achieved relative to the theoretical maximum value within the range of qualified concentrate output; the calculation formula for the recovery efficiency factor B is as follows: B=R eff / (100%×W eff ) In the above formula, R eff W is the integral area of the recovery rate-cutter radial position curve within the effective separation range. eff To effectively separate the total width of the interval.
6. The method for evaluating the separation performance of a spiral chute based on the control of a cutter and the coupling of multiple indicators as described in claim 5, characterized in that: The integral formula for the integral area of the recovery rate-cutter radial position curve within the effective separation interval is: Wherein: the effective grade threshold is βmin, and the effective separation interval is... , The curve represents the distribution of recovery rate as a function of the radial position of the cutter.
7. The method for evaluating the separation performance of a spiral chute based on the control of a cutter and the coupling of multiple indicators as described in claim 1, characterized in that: The stability coefficient S quantifies the smoothness of the separation process, and the formula for calculating the stability coefficient S is as follows: S = 1 / (1 + k × CV) Wherein, CV is the coefficient of variation of all grade measurements within the effective separation interval, and its expression is as follows: CV=σG / μG In the above formula, k is the grade fluctuation penalty weighting coefficient; σG is the standard deviation of grade within the effective separation interval; and μG is the average grade within the effective separation interval.
8. The method for evaluating the separation performance of a spiral chute based on the coupling of ore cutter control and multiple indicators as described in claim 1, characterized in that: The effective separation range is based on a set effective grade threshold. From all radial position control points of the ore cutter, all measurement points with a grade value not lower than the threshold are selected. The effective grade threshold is the lowest concentrate grade value.
9. The method for evaluating the separation performance of a spiral chute based on the control of a cutter and the coupling of multiple indicators as described in claim 1, characterized in that: The construction process of the multidimensional performance index prediction model includes: Based on the structural parameters, feeding conditions, and operating parameters of the target spiral chute; A numerical simulation model consistent with the physical processes of slurry movement and separation was constructed and run to conduct numerical simulation experiments on the movement and separation behavior of slurry in a spiral chute. Based on the results of numerical simulation experiments, data on the distribution of particles at the end of the third cycle of the spiral chute were extracted. Based on this, the concentrate grade and recovery rate corresponding to different radial positions of the cutter were calculated. A deterministic correspondence between the radial position of the cutter and each separation index was established to construct a multidimensional performance index prediction model.
10. The method for evaluating the separation performance of a spiral chute based on the control of a ore cutter and the coupling of multiple indicators as described in claim 1, characterized in that: The target spiral chute structural parameters include outer radius R, inner radius r, pitch P, downward angle γ, and number of turns N; Ore feeding conditions include mineral type, grade of valuable elements, particle size and density; Operating parameters include solid mass concentration and inlet volumetric flow rate.
Citation Information
Patent Citations
Method for investigating and optimizing feeding position of short-stroke spiral chute
CN121052002A