A method of precision grinding and sorting of minerals

Abstract

The application discloses a precise grinding and dressing method of minerals and belongs to the technical field of mineral dressing process and mineralogy. The method is characterized in that the mineral parameters of each sieve analysis particle size of a broken sample are finely analyzed, and a quantitative relationship is established between the mineral parameters and concentrate indexes of each particle size, so that the key of 'grinding on demand' and 'precise recovery' is accurately deciphered. Through the dynamic linkage of the fine classification of particle size, the mineral parameters and the grade of the target element in the concentrate, the three major pain points of 'high energy consumption, serious over-grinding and large fluctuation of concentrate quality' in the traditional grinding process are solved, and the application provides an intelligent, self-adaptive and high-benefit precise grinding and dressing solution for the mineral dressing industry.

Description

Technical Field

[0001] This invention relates to the field of mineral processing technology, and more particularly to a method for precise grinding and beneficiation of minerals. Background Technology

[0002] In the field of mineral processing, the energy consumption of the grinding process accounts for 50%-85% of the total energy consumption of a beneficiation plant. Its efficiency is directly affected by the physical properties of the ore, such as hardness (e.g., quartz has a hardness of 7, while molybdenite has a hardness of only 1-1.5), degree of cleavage development (e.g., mica and galena both have three sets of perfect cleavage), degree of fracture development (e.g., pyrite has well-developed fractures), degree of porosity development (e.g., limonite has well-developed porosity), brittleness (e.g., magnetite, ilmenite, chalcopyrite), and particle size distribution (e.g., the coarse particle size of magnetite can reach more than 3.0 mm). During the grinding process, coarse-grained minerals and minerals with high hardness tend to lead to excessive grinding energy consumption, while fine-grained minerals and minerals with low hardness, well-developed cleavage, well-developed fractures, and brittleness are prone to over-grinding, thus reducing the beneficiation recovery rate.

[0003] While modern classifying grinding has significantly reduced over-grinding, it relies heavily on manual experience to adjust equipment parameters, and the feed particle size is often too fine. Furthermore, it lacks refined analysis of the parameters associated with different particle sizes and minerals. Traditional processes have not established quantitative relationships between particle size and mineral liberation degree, as well as concentrate indicators, making it difficult to achieve "on-demand grinding," resulting in resource waste and increased energy consumption.

[0004] The existing technology has the following problems: First, there is an imbalance between energy consumption and efficiency. The energy intensity of traditional grinding far exceeds the international advanced level, while the concentrate recovery rate is only 75%-85%. Second, over-grinding and under-grinding coexist. Over-grinding of fine particles leads to increased consumption of flotation reagents, while under-grinding of coarse particles reduces the efficiency of subsequent separation. Third, there is the data silo effect. Grinding parameters (speed, concentration), mineral parameters (mineral type, particle size, degree of liberation), concentrate indicators and mineral processing flow design have not achieved cross-scale correlation, which restricts process optimization.

[0005] Although Industry 4.0 technologies (such as machine vision and digital twins) are gradually penetrating the mineral processing field, the industry is transforming from "experience-driven" to "data-driven." However, existing intelligent mineral processing systems mostly focus on image recognition or flotation reagent optimization, and lack sufficient understanding of the correlation between mineral parameters (such as mineral type, particle size, and degree of liberation) and corresponding concentrate indicators at different sieve sizes of crushed samples. Furthermore, existing intelligent models are mostly based on single parameters (such as particle size or hardness), lacking multi-dimensional coupling analysis capabilities, making it difficult to achieve precise control of grinding. Summary of the Invention

[0006] This invention provides a method for precise grinding and beneficiation of minerals, which can quickly and accurately design the most economical grinding and beneficiation process before mineral processing.

[0007] To address the technical problems mentioned in the background section, the present invention proposes the following technical solution:

[0008] A method for precise grinding and beneficiation of minerals, comprising the following steps:

[0009] S1. The crushed sample is further subdivided into n particle sizes for sieve analysis to obtain the yield γ1~γ of each sieve size size. n and the target element grades α1~α of each sieve particle size fraction n ;

[0010] S2. Select samples from each sieve particle size fraction and detect the element content D of the target element in the target mineral and the degree of liberation B of the target mineral in each sieve particle size fraction; calculate the grade β of the target element in the concentrate after recovering all target minerals in each sieve particle size fraction based on the element content D, degree of liberation B and mineral parameter C.

[0011] S3. Compare the target element grade β with the industry standard. If the element grade β is greater than or equal to the value specified in the industry standard starting from a certain sieve particle size, then the sieve particle size and the sieve particle size below it meet the fineness requirements and no further grinding is required.

[0012] S4, when a certain sieve particle size A n When the grade β of the target element is close to but lower than the value specified in the industry standard, the sieve particle size is mixed with the sieve particle sizes below it to obtain a mixed particle size. The elemental distribution rate F of the target element in each sieve particle size of the mixed particle size is calculated. The degree of liberation b of the target mineral in the mixed particle size is calculated based on the elemental distribution rate F and the degree of liberation B. The grade β of the target element in the concentrate after recovering all the target minerals in the mixed particle size is calculated based on the degree of liberation b and the mineral parameter C. 混 ;

[0013] S5. The grade β of the target element 混 Compared with industry standards, when the grade β of the target element in the mixed particle size is... 混 If the value is greater than or equal to the value specified in the industry standard, then the sieve particle size A... n All particle sizes below the specified size meet the fineness requirements and do not require further grinding; when the target element grade β of the mixed particle size is... 混 If the value is lower than the value specified in the industry standard, then the sieve particle size A... n If the particle size at or above the screening size does not meet the fineness requirements, further grinding is required.

[0014] S6. Mix all the sieve particles that do not meet the fineness requirements and need to be ground again to obtain mixed particles. Calculate the element distribution rate F of the target element in each sieve particle size of the mixture. Calculate the degree of liberation b of the target mineral in the mixed particles based on the element distribution rate F and the degree of liberation B. Calculate the grade θ of the target element corresponding to different intergrowths in the concentrate after recovering all the target minerals under the mixed particles based on the degree of liberation b and the mineral parameter C.

[0015] S7. Recover intergrowths with a target element grade θ greater than or equal to the value specified in the industry standard, and re-grind and beneficiate intergrowths with a target element grade θ less than the value specified in the industry standard.

[0016] As a further preferred embodiment of the above technical solution, the degree of liberation B and degree of liberation b of the target mineral both include the degree of liberation of the target mineral as a single organism, the degree of liberation of 3 / 4≤intergrowth<1, the degree of liberation of 2 / 4≤intergrowth<3 / 4, the degree of liberation of 1 / 4≤intergrowth<2 / 4, and the degree of liberation of intergrowth<1 / 4.

[0017] As a further preferred embodiment of the above technical solution, the grade β of the target element is calculated using the following formula:

[0018] Among them, B0 to B4 correspond to the degree of liberation of the target mineral, respectively: 3 / 4≤intergrowth<1 degree of liberation, 2 / 4≤intergrowth<3 / 4 degree of liberation, 1 / 4≤intergrowth<2 / 4 degree of liberation and intergrowth<1 / 4 degree of liberation;

[0019] The grade β of the target element 混 The calculation is performed using the following formula:

[0020] Wherein, b0 to b4 correspond to the degree of liberation of the target mineral as a single mineral, 3 / 4≤intergrowth<1 degree of liberation, 2 / 4≤intergrowth<3 / 4 degree of liberation, 1 / 4≤intergrowth<2 / 4 degree of liberation, and intergrowth<1 / 4 degree of liberation, respectively.

[0021] The mineral parameter C includes constants C0 to C4. The constant C0 for a single organism is 1, the constant C1 for 3 / 4 ≤ intergrowth < 1 is 1.1429, the constant C2 for 2 / 4 ≤ intergrowth < 3 / 4 is 1.6, the constant C3 for 1 / 4 ≤ intergrowth < 2 / 4 is 2.667, and the constant C4 for intergrowth < 1 / 4 is 8.

[0022] As a further preferred embodiment of the above technical solution, in S4 and S6, the degree of dissociation b is the cumulative product of the degree of dissociation B of the target mineral in each sieve particle size fraction and the corresponding elemental distribution rate F. The degree of dissociation b is calculated using the following formula:

[0023] Where x is an integer from 0 to 4; F i Let be the elemental distribution rate of the i-th sieved particle size in the mixed particle size.

[0024] As a further preferred embodiment of the above technical solution, in S4 and S6, the elemental distribution rate F of the target element in each sieve particle size fraction of the mixture is calculated using the following formula:

[0025] In the formula, F i F represents the elemental distribution of the i-th sieved particle size fraction in the mixed particle size fraction. 总 It is the sum of the product of the yield of each sieved particle size fraction in the mixed particle size fraction and the grade of the target element.

[0026] As a further optimization of the above technical solution, the target element grades θ in the concentrate corresponding to different intergrowths after recovering all target minerals in the mixed particle size distribution include θ0~θ4, which correspond to the target element grades when only monomers are recovered, when monomers and ≥3 / 4 of intergrowths are recovered, when monomers and ≥2 / 4 of intergrowths are recovered, when monomers and ≥1 / 4 of intergrowths are recovered, and when all monomers and intergrowths are recovered, respectively; θ0~θ4 are calculated using the following formula:

[0027] ;

[0028] ;

[0029] ;

[0030] ;

[0031] .

[0032] As a further preferred embodiment of the above technical solution, in S1, the crushed sample is further subdivided into 9 particle sizes for sieve analysis. The particle sizes for each sieve analysis are: L1=+0.83mm, L2=-0.83+0.5mm, L3=-0.5+0.3mm, L4=-0.3+0.15mm, L5=-0.15+0.075mm, L6=-0.075+0.048mm, L7=-0.048+0.038mm, L8=-0.038+0.025mm, and L9=-0.025mm.

[0033] As a further optimization of the above technical solution, flotation or magnetic separation is used to recover the sieved particle size that meets the fineness requirements and does not need to be ground again. For the sieved particle size that does not meet the fineness requirements and needs to be ground again, magnetic separation or gravity separation is used to accurately recover the intergrowths corresponding to the target element grade θ being greater than or equal to the value specified in the industry standard. For the intergrowths with the target element grade θ being less than the value specified in the industry standard, they are ground and beneficiated again.

[0034] The present invention has the following beneficial effects:

[0035] Compared with existing technologies, this invention, on the one hand, automatically adjusts the screening threshold and reduces over-grinding by establishing a correlation model between the concentrate grade and particle size parameters of each sieved particle size fraction of the crushed sample; on the other hand, it establishes a coupling model between "concentrate grade and intergrowth type" for each particle size fraction, transforming traditional coarse grinding into targeted dissociation. This invention solves the three major pain points of traditional grinding processes—high energy consumption, severe over-grinding, and large fluctuations in concentrate quality—by dynamically linking fine particle size classification with mineral parameters and the grade of target elements in the concentrate. It provides the mineral processing industry with an intelligent, adaptive, and highly efficient precision grinding and beneficiation solution. Attached Figure Description

[0036] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0037] Figure 1 This is a technical roadmap for the precise grinding and beneficiation method for minerals according to the present invention. Detailed Implementation

[0038] The present invention will be described in detail below with reference to the accompanying drawings and embodiments, but the present invention can be implemented in many different ways as defined and covered by the claims.

[0039] Example 1:

[0040] This embodiment presents a precise grinding and beneficiation method based on the decoding of mineral parameters at various sieve particle sizes of crushed samples. The technical route is as follows: Figure 1 As shown, it includes the following steps:

[0041] S1. The broken samples are sieved according to particle sizes L1=+0.83mm, L2=-0.83+0.5mm, L3=-0.5+0.3mm, L4=-0.3+0.15mm, L5=-0.15+0.075mm, L6=-0.075+0.048mm, L7=-0.048+0.038mm, L8=-0.038+0.025mm, and L9=-0.025mm. The yield of each sieve size is determined and denoted as γ1, γ2, γ3, γ4, γ5, γ6, γ7, γ8, and γ9, respectively. The grade of the target element in each sieve size is determined and denoted as α1, α2, α3, α4, α5, α6, α7, α8, and α9, respectively. The distribution rate F of the target element in each sieve size sample is calculated using the following method:

[0042] Distribution rate of target element:

[0043] ;

[0044] Where n = 1, 2, 3, 4, 5, 6, 7, 8, 9, F1 represents the proportion of the target element in the L1 = +0.83 mm particle size fraction of the crushed sample, F2 represents the proportion of the target element in the L2 = -0.83 +0.5 mm particle size fraction of the crushed sample, F3 represents the proportion of the target element in the L3 = -0.5 +0.3 mm particle size fraction of the crushed sample, F4 represents the proportion of the target element in the L4 = -0.3 +0.15 mm particle size fraction of the crushed sample, and F5 represents the proportion of the target element in the L5 = -0.15 mm particle size fraction of the crushed sample. F6 represents the proportion of the target element in the +0.075mm particle size fraction of the crushed sample; F7 represents the proportion of the target element in the L7=-0.048+0.038mm particle size fraction of the crushed sample; F8 represents the proportion of the target element in the L8=-0.038+0.025mm particle size fraction of the crushed sample; and F9 represents the proportion of the target element in the L9=-0.025mm particle size fraction of the crushed sample.

[0045] S2. Select representative samples from each sieve particle size fraction to prepare optical discs, then detect the content of the target element in the target mineral in each sample, denoted as D; determine the degree of liberation of the target mineral B in each sample; and calculate the grade β of the target element in the concentrate after recovering all target mineral particles in each sieve particle size fraction based on mineral parameters. The calculation method is as follows:

[0046] Among them, B0 to B4 correspond to the degree of liberation of the target mineral, respectively: 3 / 4≤intergrowth<1 degree of liberation, 2 / 4≤intergrowth<3 / 4 degree of liberation, 1 / 4≤intergrowth<2 / 4 degree of liberation and intergrowth<1 / 4 degree of liberation.

[0047] S3. Compare the grade of the target element in the concentrate of each of the above sieve particle sizes with the industry standard. When the concentrate grade reaches or exceeds the value of the industry standard starting from a certain sieve particle size, then the samples of that sieve particle size and below are all qualified fineness samples and do not need to be ground again.

[0048] S4. When the grade of a certain sieve particle size concentrate is close to but does not meet the industry standard, this particle size and smaller particle sizes are mixed to obtain a mixed particle size. The elemental distribution rate F of the target element in each of the mixed sieve particle sizes is calculated. Based on the elemental distribution rate F and the degree of liberation B, the degree of liberation b of the target mineral in the mixed sample is calculated. Then, based on this degree of liberation, the grade β of the target element in the concentrate after recovering all target mineral particles in the mixed particle size is calculated. 混 .

[0049] The degree of liberation 'b' of the target mineral in the mixed sample is calculated as follows:

[0050] degree of dissociation Where x = 0, 1, 2, 3, 4, F i Let b0 be the elemental distribution rate of the i-th sieve size fraction in the mixed size fraction. b0 refers to the cumulative product of the degree of liberation of the target mineral in each size fraction (B0) and the distribution rate of the target element in each size fraction (F); b1 refers to the cumulative product of the degree of liberation of the target mineral in each size fraction (3 / 4≤intergrowth<1) (B1) and the distribution rate of the target element in each size fraction (F); b2 refers to the cumulative product of the degree of liberation of the target mineral in each size fraction (2 / 4≤intergrowth<3 / 4) (B2) and the distribution rate of the target element in each size fraction (F); b3 refers to the cumulative product of the degree of liberation of the target mineral in each size fraction (1 / 4≤intergrowth<2 / 4) (B3) and the distribution rate of the target element in each size fraction (F); b4 refers to the cumulative product of the degree of liberation of the target mineral in each size fraction (intergrowth<1 / 4) (B4) and the distribution rate of the target element in each size fraction (F).

[0051] The elemental distribution F of the target element in each sieve fraction of the mixture is calculated using the following formula:

[0052] In the formula, F i F represents the elemental distribution of the i-th sieved particle size fraction in the mixed particle size fraction. 总 It is the sum of the product of the yield of each sieved particle size fraction in the mixed particle size fraction and the grade of the target element.

[0053] S5. When the grade of the target element in the concentrate after recovering all target mineral particles in the mixed particle size distribution in the above steps reaches or exceeds the industry standard value, then the samples of this particle size distribution and below are all qualified fineness samples and do not need to be ground again; if the grade of the target element in the concentrate after recovering all target mineral particles in the mixed particle size distribution in the above steps does not reach the industry standard value, then the degree of liberation of the target mineral in this particle size distribution is insufficient and it needs to be ground again.

[0054] S6. Mix all particle sizes corresponding to the values ​​of the target element in the concentrate that do not meet the industry standard to obtain a mixed particle size. Calculate the elemental distribution rate F of the target element in each sieve particle size of the mixed particle size. Based on the elemental distribution rate F and the degree of liberation B, calculate the degree of liberation b of the target mineral in the mixed sample. Then, based on this degree of liberation, calculate the grade θ of the target element recovered from different types of intergrowth concentrates under the mixed particle size. The calculation method is as follows:

[0055] ;

[0056] Where n=4, the degree of dissociation of the monomer is denoted as b0, the degree of dissociation of 3 / 4 ≤ internode < 1 is denoted as b1, the degree of dissociation of 2 / 4 ≤ internode < 3 / 4 is denoted as b2, the degree of dissociation of 1 / 4 ≤ internode < 2 / 4 is denoted as b3, and the degree of dissociation of internode < 1 / 4 is denoted as b4. The constants corresponding to the monomer are C0=1, C1=1.1429, C2=1.6, C3=2.667, and C4=8.

[0057] When only monomers are recovered, the method for predicting the grade of the target element in the concentrate of mixed particle sizes is as follows:

[0058] The quality of the target element ;

[0059] When recovering monomers and ≥3 / 4 of intergrowths, the method for predicting the grade of the target element in the concentrate of mixed particle size is as follows:

[0060] The quality of the target element ;

[0061] When recovering monomers and ≥2 / 4 of intergrowths, the method for predicting the grade of the target element in the concentrate of mixed particle size is as follows:

[0062] The quality of the target element ;

[0063] When recovering monomers and ≥1 / 4 of intergrowths, the method for predicting the grade of the target element in the concentrate of mixed particle size is as follows:

[0064] The quality of the target element ;

[0065] The method for predicting the grade of the target element in the concentrate of mixed particle sizes is as follows: All particles containing the target mineral are recovered.

[0066] The quality of the target element .

[0067] S7. Accurately recover the intergrowth types corresponding to the above-mentioned concentrate grades that reach or even exceed the industry standard, and then perform precise grinding on the intergrowth types that affect the concentrate grade.

[0068] For the particle size fractions that do not require grinding as determined by the above steps, these fractions and smaller can be precisely recovered by flotation or magnetic separation; while the fractions larger than these fractions are precisely recovered by magnetic separation or gravity separation, and the tailings are regrinded and re-selected.

[0069] Example 2:

[0070] To ensure the accuracy and feasibility of the mineral grinding and beneficiation method in Example 1, the following practical application example is provided: A tungsten ore sample with a -2mm crushed size contains 0.26% WO3. The main tungsten minerals in the ore are wolframite and scheelite; other metallic minerals include chalcopyrite, bismuthite, native bismuth, pyrrhotite, pyrite, sphalerite, and molybdenite; gangue minerals are mainly quartz, followed by feldspar, mica, and chlorite. Wolframite and scheelite account for 0.23% and 0.11% of the total minerals, respectively; wolframite and scheelite contain 76.20% and 78.61% WO3, respectively, and the average WO3 content in the tungsten minerals is 76.98%, which is the D value. The sieve analysis results of the -2mm crushed sample are shown in Table 1. Table 2 lists the degree of liberation of tungsten minerals in different sieve sizes of the -2mm crushed sample, and Table 3 shows the WO3 grade in the concentrate from which all tungsten minerals were recovered in different sieve sizes of the -2mm crushed sample.

[0071] Table 1: Sieve analysis results of -2mm broken samples / %

[0072]

[0073] The steps for calculating the elemental distribution of each particle size fraction in a -2mm crushed sample are as follows:

[0074] Cumulative values ​​of the distribution rate of target elements at each particle size: ;

[0075] Distribution rate of target elements in L1: ;

[0076] Distribution rate of the target element in L2: ;

[0077] Distribution rate of target elements in L3: ;

[0078] Distribution rate of target elements in L4: ;

[0079] Distribution rate of target elements in L5: ;

[0080] Distribution rate of the target element in L6: ;

[0081] Distribution rate of the target element in L7: ;

[0082] Distribution rate of the target element in L8: ;

[0083] Distribution rate of the target element in L9: ;

[0084] Table 2: Degree of liberation of tungsten minerals in different sieve sizes of -2mm crushed samples / %

[0085]

[0086] The steps for calculating the grade of the target element WO3 in the concentrate after recovering all target mineral particles from each sieve size of a -2mm crushed sample are as follows:

[0087] L1: ;

[0088] L2: ;

[0089] L3: ;

[0090] L4: ;

[0091] L5: ;

[0092] L6: ;

[0093] L7: ;

[0094] L8: ;

[0095] L9: .

[0096] Table 3: WO3 grade (%) in concentrates from which all tungsten minerals were recovered after different sieve particle sizes of -2mm crushed samples

[0097]

[0098] As shown in Table 3, the WO3 grades in the concentrates of different particle sizes, L4=-0.3+0.15mm, L5=-0.15+0.075mm, L6=-0.075+0.048mm, L7=-0.048+0.038mm, L8=-0.038+0.025mm and L9=-0.025mm, are as high as 69.24%, 70.15%, 72.65%, 73.14%, and 74%, respectively. The percentages of 0.29% and 75.04% both exceed the industry standard WO3 grade (≥65%) for mixed tungsten concentrate. Clearly, the tungsten minerals in the particle sizes of L4=-0.3+0.15mm, L5=-0.15+0.075mm, L6=-0.075+0.048mm, L7=-0.048+0.038mm, L8=-0.038+0.025mm, and L9=-0.025mm have excellent liberation and do not require further grinding.

[0099] The WO3 grade in the L3=-0.5+0.3mm particle size concentrate was 60.09%, which did not meet the industry standard. However, when mixed with six other particle sizes, namely L4=-0.3+0.15mm, L5=-0.15+0.075mm, L6=-0.075+0.048mm, L7=-0.048+0.038mm, L8=-0.038+0.025mm and L9=-0.025mm, the sample still showed good dissociation (as shown in Table 4).

[0100] Table 4: Liberation degree of tungsten minerals in the -0.50mm particle size fraction and WO3 grade (%) in all recovered concentrate

[0101]

[0102] The above seven particle size fractions were mixed to form a -0.5 mm sample. Based on the proportion of the target element distribution rate F in each particle size fraction to the sum of the target mineral distribution rates in all particle size fractions, the proportion of the target element in each of the seven particle size fractions to the sum of the target mineral distribution rates in all particle size fractions was calculated (Table 1). The calculation steps are as follows:

[0103] The proportion of the target element in the mixed sample in L3: ;

[0104] The proportion of the target element in the mixed sample in L4:

[0105] ;

[0106] The proportion of the target element in the mixed sample in L5:

[0107] ;

[0108] The proportion of the target element in the mixed sample in L6:

[0109] ;

[0110] The proportion of the target element in the mixed sample in L7:

[0111] ;

[0112] The proportion of the target element in the mixed sample in L8:

[0113] ;

[0114] The proportion of the target element in the mixed sample in L9:

[0115] ;

[0116] The above seven particle size fractions were mixed to form a -0.5 mm sample. Based on the distribution rate F and degree of liberation B of the target element in each particle size fraction, the degree of liberation b of the target mineral in the mixed sample was calculated. The calculation steps are as follows:

[0117] Monomer dissociation degree:

[0118] ;

[0119] 3 / 4 ≤ interstices < 1 degree of dissociation: ;

[0120] 2 / 4 ≤ interstices < 3 / 4 degree of dissociation: ;

[0121] 1 / 4 ≤ intergrowth < 2 / 4 degree of dissociation:

[0122] ;

[0123] Intergrowth <1 / 4 dissociation:

[0124] .

[0125] The above seven particle size fractions are mixed (i.e., -0.5 mm particle size fraction). Based on the degree of liberation corresponding to the above seven sieve particle size fractions, the WO3 grade in the concentrate from which all tungsten mineral particles are recovered under the mixed particle size fraction is calculated. The calculation steps are as follows:

[0126] ;

[0127] Clearly, the WO3 grade in the concentrate after mixing the -0.5mm particle size samples is as high as 67.11%, and obviously, the particles smaller than -0.5mm in the -2mm crushed sample do not need to be re-ground.

[0128] Table 5: Degree of liberation of tungsten minerals in the +0.50mm grain size fraction / %

[0129]

[0130] The WO3 grades in the L1=+0.83mm and L2=-0.83+0.5mm particle size concentrates are only 30.60% and 48.61% respectively, far below the industry standard. The two particle size samples were mixed (i.e., +0.5mm). Based on the proportion of the target element distribution rate F in each particle size to the sum of the target mineral distribution rates in all particle size sizes, the proportion of the target element in the two particle size sizes to the sum of the target mineral distribution rates in all particle size sizes was calculated (Table 1). The calculation steps are as follows:

[0131] The proportion of the target element in the mixed sample in L1: ;

[0132] The proportion of the target element in the mixed sample in L2: .

[0133] The above two particle size fractions were mixed to form a +0.5 mm sample. Based on the distribution rate F and degree of liberation B of the target element in each particle size fraction, the degree of liberation b of the target mineral in the mixed sample was calculated (Table 5). The calculation steps are as follows:

[0134] Monomer dissociation degree: ;

[0135] 3 / 4 ≤ interstices < 1 degree of dissociation: ;

[0136] 2 / 4 ≤ interstices < 3 / 4 degree of dissociation: ;

[0137] 1 / 4 ≤ intergrowth < 2 / 4 degree of dissociation: ;

[0138] Intergrowth <1 / 4 dissociation: .

[0139] Calculation method of WO3 grade θ in concentrate of +0.5mm mixed sample (Table 6):

[0140] When only monomers are recovered, the method for predicting the WO3 grade of the target element in the +0.5mm particle size concentrate is as follows:

[0141] ;

[0142] When recovering monomers and ≥3 / 4 of intergrowths, the method for predicting the grade of the target element in the +0.5mm particle size concentrate is as follows:

[0143] ;

[0144] When recovering monomers and ≥2 / 4 of intergrowths, the method for predicting the grade of the target element in the +0.5mm particle size concentrate is as follows:

[0145] ;

[0146] When recovering monomers and ≥1 / 4 of intergrowths, the method for predicting the grade of the target element in the +0.5mm particle size concentrate is as follows:

[0147] ;

[0148] When recovering all tungsten-containing mineral particles, the method for predicting the grade of the target element in the +0.5mm particle size concentrate is as follows:

[0149] .

[0150] Table 6: WO3 grade (%) in +0.50mm particle size concentrate

[0151]

[0152] Clearly, a certain amount of qualified mixed tungsten concentrate with a WO3 grade of over 65% can still be obtained from the +0.5mm particle size mixed sample. However, the excessively high proportion of tungsten mineral intergrowths (<2 / 4) is the main reason affecting the quality of the +0.5mm particle size concentrate, and this part is also the target for regrinding.

[0153] In summary, tungsten mineral intergrowths comprising less than 2 / 4 of the +0.5mm particle size are the target for regrinding. Precise recovery of single tungsten mineral intergrowths comprising ≥2 / 4 of the +0.5mm particle size and all tungsten mineral particles in the -0.5mm particle size can yield mixed tungsten concentrate with a WO3 grade of over 65%. Considering mineral type and particle size, the -0.5mm particle size sample can yield mixed tungsten concentrate with a WO3 grade of over 65% through flotation; the +0.5mm particle size sample can yield mixed tungsten concentrate with a WO3 grade of over 65% through gravity separation. The gravity separation tailings are then regrinded and re-separated.

[0154] The above description is merely a preferred embodiment of the present invention, and the scope of protection of the present invention is not limited to the above embodiments. For those skilled in the art, improvements and modifications obtained without departing from the inventive concept should also be considered within the scope of protection of the present invention.

[0155] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A method for precise grinding and beneficiation of minerals, characterized in that, Includes the following steps: S1. The crushed sample is further subdivided into n particle sizes for sieve analysis to obtain the yield γ1~γ of each sieve size size. n and the target element grades α1~α of each sieve particle size fraction n ; S2. Select samples from each sieve particle size fraction and detect the element content D of the target element in the target mineral and the degree of liberation B of the target mineral in each sieve particle size fraction; calculate the grade β of the target element in the concentrate after recovering all target minerals in each sieve particle size fraction based on the element content D, degree of liberation B and mineral parameter C. S3. Compare the target element grade β with the industry standard. If the element grade β is greater than or equal to the value specified in the industry standard starting from a certain sieve particle size, then the sieve particle size and the sieve particle size below it meet the fineness requirements and no further grinding is required. S4, when a certain sieve particle size A n When the grade β of the target element is close to but lower than the value specified in the industry standard, the sieve particle size is mixed with the sieve particle sizes below it to obtain a mixed particle size. The elemental distribution rate F of the target element in each sieve particle size of the mixed particle size is calculated. The degree of liberation b of the target mineral in the mixed particle size is calculated based on the elemental distribution rate F and the degree of liberation B. The grade β of the target element in the concentrate after recovering all the target minerals in the mixed particle size is calculated based on the degree of liberation b and the mineral parameter C. 混 ; S5. The grade β of the target element 混 Compared with industry standards, when the grade β of the target element in the mixed particle size is... 混 If the value is greater than or equal to the value specified in the industry standard, then the sieve particle size A... n All particle sizes below the specified size meet the fineness requirements and do not require further grinding; when the target element grade β of the mixed particle size is... 混 If the value is lower than the value specified in the industry standard, then the sieve particle size A... n If the particle size at or above the screening size does not meet the fineness requirements, further grinding is required. S6. Mix all the sieve particles that do not meet the fineness requirements and need to be ground again to obtain mixed particles. Calculate the element distribution rate F of the target element in each sieve particle size of the mixture. Calculate the degree of liberation b of the target mineral in the mixed particles based on the element distribution rate F and the degree of liberation B. Calculate the grade θ of the target element corresponding to different intergrowths in the concentrate after recovering all the target minerals under the mixed particles based on the degree of liberation b and the mineral parameter C. S7. Recover intergrowths with a target element grade θ greater than or equal to the value specified in the industry standard, and re-grind and beneficiate intergrowths with a target element grade θ less than the value specified in the industry standard.

2. The method for precise grinding and beneficiation of minerals according to claim 1, characterized in that, The degree of liberation B and degree of liberation b of the target mineral both include the degree of liberation of the target mineral as a single organism, the degree of liberation of 3 / 4 ≤ intergrowth < 1, the degree of liberation of 2 / 4 ≤ intergrowth < 3 / 4, the degree of liberation of 1 / 4 ≤ intergrowth < 2 / 4, and the degree of liberation of intergrowth < 1 / 4.

3. The method for precise grinding and beneficiation of minerals according to claim 2, characterized in that, The grade β of the target element is calculated using the following formula: Among them, B0 to B4 correspond to the degree of liberation of the target mineral, respectively: 3 / 4≤intergrowth<1 degree of liberation, 2 / 4≤intergrowth<3 / 4 degree of liberation, 1 / 4≤intergrowth<2 / 4 degree of liberation and intergrowth<1 / 4 degree of liberation; The grade β of the target element 混 The calculation is performed using the following formula: Wherein, b0 to b4 correspond to the degree of liberation of the target mineral as a single mineral, 3 / 4≤intergrowth<1 degree of liberation, 2 / 4≤intergrowth<3 / 4 degree of liberation, 1 / 4≤intergrowth<2 / 4 degree of liberation, and intergrowth<1 / 4 degree of liberation, respectively. The mineral parameter C includes constants C0 to C4. The constant C0 for a single organism is 1, the constant C1 for 3 / 4 ≤ intergrowth < 1 is 1.1429, the constant C2 for 2 / 4 ≤ intergrowth < 3 / 4 is 1.6, the constant C3 for 1 / 4 ≤ intergrowth < 2 / 4 is 2.667, and the constant C4 for intergrowth < 1 / 4 is 8.

4. The method for precise grinding and beneficiation of minerals according to claim 3, characterized in that, In S4 and S6, the degree of liberation b is the cumulative product of the degree of liberation B of the target mineral in each sieve particle size fraction and the corresponding elemental distribution rate F. The degree of liberation b is calculated using the following formula: Where x is an integer from 0 to 4; F i Let be the elemental distribution rate of the i-th sieved particle size in the mixed particle size.

5. The method for precise grinding and beneficiation of minerals according to claim 4, characterized in that, In S4 and S6, the elemental distribution rate F of the target element in each sieve particle size fraction of the mixture is calculated using the following formula: In the formula, F i F represents the elemental distribution of the i-th sieved particle size fraction in the mixed particle size fraction. 总 It is the sum of the product of the yield of each sieved particle size fraction in the mixed particle size fraction and the grade of the target element.

6. The method for precise grinding and beneficiation of minerals according to claim 3, characterized in that, The target element grades θ in the concentrate after recovering all target minerals in the mixed particle size distribution include θ0~θ4, which correspond to the target element grades when only the monomer is recovered, when the monomer and ≥3 / 4 of the intergrowth are recovered, when the monomer and ≥2 / 4 of the intergrowth are recovered, when the monomer and ≥1 / 4 of the intergrowth are recovered, and when all the monomers and intergrowths are recovered, respectively. θ0~θ4 are calculated using the following formula: ； ； ； ； 。 7. The method for precise grinding and beneficiation of minerals according to any one of claims 1-6, characterized in that, In S1, the broken sample is further subdivided into 9 particle sizes for sieve analysis. The particle sizes for each sieve are: L1 = +0.83 mm, L2 = -0.83 + 0.5 mm, L3 = -0.5 + 0.3 mm, L4 = -0.3 + 0.15 mm, L5 = -0.15 + 0.075 mm, L6 = -0.075 + 0.048 mm, L7 = -0.048 + 0.038 mm, L8 = -0.038 + 0.025 mm, and L9 = -0.025 mm.

8. The method for precise grinding and beneficiation of minerals according to any one of claims 1-6, characterized in that, For sieved particles that meet the fineness requirements and do not need further grinding, flotation or magnetic separation is used for recovery. For sieved particles that do not meet the fineness requirements and need further grinding, magnetic separation or gravity separation is used to accurately recover intergrowths with a target element grade θ greater than or equal to the value specified in the industry standard. Intergrowths with a target element grade θ less than the value specified in the industry standard are subjected to further grinding and beneficiation.

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