Method for evaluating the quality of a flotation concentrate

Abstract

The present application relates to the technical field of mineral processing, and particularly provides a flotation concentrate quality evaluation method. The flotation concentrate quality evaluation method combines multiple parameters such as concentrate grade, harmful impurity content, yield, mineral particle size characteristics and dissociation degree characteristics to perform systematic and quantitative comprehensive evaluation, and can provide accurate data support for concentrate quality determination and optimization of beneficiation process.

Description

Technical Field

[0001] This invention relates to the field of mineral processing technology, and specifically to a method for evaluating the quality of flotation concentrate. Background Technology

[0002] In mineral processing, the quality of concentrate directly determines its economic value and the feasibility of downstream smelting or application. Currently, the industry's evaluation of concentrate quality relies on a single or a few indicators, mainly focusing on the content of major useful elements in the concentrate grade, supplemented by restrictions on individual harmful impurities such as sulfur, phosphorus, and arsenic.

[0003] Existing evaluation methods have significant limitations:

[0004] (1) One-sidedness. High-grade concentrate may be accompanied by low yield, which means low resource recovery rate and the overall economic benefits may not be optimal. Similarly, focusing only on the grade of major elements and harmful impurities may ignore the key impact of mineralogical characteristics on subsequent processes.

[0005] (2) Neglecting process adaptability. The particle size distribution and mineral liberation degree of the concentrate directly affect the efficiency of subsequent filtration, transportation, sintering, or smelting. For example, excessively fine particle size can lead to filtration difficulties and increased energy consumption; high content of intergrowths can cause metal loss and increased energy consumption during smelting. Existing evaluation systems rarely incorporate these process adaptability indicators into a unified quantitative evaluation framework.

[0006] (3) Insufficient basis for decision-making. When faced with multiple batches of concentrate produced under different operating conditions, or when comparing the optimization effects of different beneficiation processes, it is difficult to make scientific and optimal decisions based solely on scattered indicators. Production personnel often have to weigh the pros and cons between "high grade and low yield" and "lower grade and high yield" based on experience, lacking an objective and comprehensive evaluation standard.

[0007] Therefore, developing a quantitative evaluation method that can comprehensively reflect the economic value, technological performance, and adaptability of concentrate to downstream processes is of great significance for guiding the optimization of mineral processing production and improving overall technical and economic indicators. Summary of the Invention

[0008] Therefore, it is necessary to provide a method for evaluating the quality of flotation concentrate.

[0009] The present invention adopts the following technical solution:

[0010] This invention provides a method for evaluating the quality of flotation concentrate, comprising the following steps: obtaining raw ore samples and concentrate samples; taking samples separately, subjecting them to embedding and solidification, grinding and polishing, carbon spraying, and performing automated mineralogical analysis; obtaining the target mineral content Ci, the target element content Ci', the harmful element content Eg, the target mineral particle size distribution characteristics Di.d, and the proportion of the target mineral in the liberated state Li.f in the raw ore sample, wherein i is a natural number and refers to different target minerals, g is a natural number and refers to different harmful elements, d is a natural number and refers to different particle size ranges, and f takes values ​​1, 2, and 3 to refer to the single state, rich intergrowth state, and poor intergrowth state of the target mineral, respectively;

[0011] Calculate the theoretical grade Hi of the raw ore: Hi = ∑Ci Ci' / ∑Ci,

[0012] Calculate the degree of liberation Li of the recoverable target mineral in the raw ore: Li = Li.1 + Li.2,

[0013] Calculate the content Di of the target mineral within the preset grain size range: Di = ΣCi Di.d,

[0014] The content of the target mineral (ci), the content of harmful elements (eg), the particle size distribution characteristics of the target mineral (di.d), the proportion of the target mineral in the liberated state (li.f), the concentrate grade (hi), and the concentrate yield (r) of the concentrate sample were obtained.

[0015] Calculate the degree of liberation of the recoverable target mineral li in the concentrate:

[0016] li=K li.1+li.2, where K is the monomer recovery coefficient, ranging from 0.50 to 1.00;

[0017] Calculate the recoverable target mineral content in the raw ore: Lij = ∑Ci Li;

[0018] Calculate the recoverable target mineral content in the concentrate: lij = ∑ci li;

[0019] Calculate the content di of the target mineral in the concentrate within the preset particle size range: di = Σci di.d,

[0020] Calculate the theoretical flotation yield R of the concentrate: R = ∑Ci;

[0021] Calculate the overall quality index W of the concentrate:

[0022] W=T1-m T2+n T3+(mn) T4=(hi R) / (Hi r)-m r Σeg / ΣEg+n r di / Di+(mn) r lij / Lij, m takes values ​​from 0.05 to 0.30, n takes values ​​from 0.01 to 0.20, and n ≤ m.

[0023] T1 represents the basic grade score, which reflects the recovery efficiency and enrichment ratio of the target mineral. The higher the value, the higher the sorting efficiency.

[0024] T2 represents the harmful impurity score, and m is the harmful impurity score coefficient, with a value ranging from 0.05 to 0.30. It reflects the enrichment degree of harmful elements, that is, the adverse effect of harmful impurities on concentrate quality. The lower this value, the better.

[0025] T3 represents the particle size characteristic score, where n is the particle size characteristic score coefficient, with a value ranging from 0.01 to 0.20, and n is less than or equal to m. T3 reflects the suitability of the concentrate particle size composition for subsequent processing (such as filtration and smelting), and the proportion of the preferred particle size within the preset particle size range is considered better, with a higher value being more desirable.

[0026] Particle size characteristics can be adjusted according to actual production conditions; particle size characteristic parameters Di and di for raw ore and concentrate: the proportion of particle size ranges Di.d and di.d within the preset particle size range is based on the weighted average of mineral content, indicating the degree of enrichment of that particle size in the concentrate.

[0027] T4 represents the degree of liberation characteristic score, and (mn) is the degree of liberation characteristic score coefficient. T4 reflects the impact of the degree of liberation on the flotation concentrate, and a higher value is better. In particular, key parameters such as particle size range d, type of harmful element g, liberation state limit f, coefficients m and n can be adjusted according to the specific ore type and the production target of the concentrator.

[0028] Preferably, the flotation concentrate quality evaluation method further includes a ball milling pretreatment step on the raw ore sample, with a grinding fineness of -200 mesh and a content of 65-95%. The sampling mass is 3-5g. The embedding and curing adopts an epoxy resin curing system.

[0029] Preferably, the grinding and polishing process involves: cutting the cured insert into sections and re-inserting it to ensure flatness, followed by grinding and polishing. Grinding uses abrasives of 1000 grit or higher until the surface is smooth; polishing uses diamond polishing compound with a particle size of 1.0 μm or lower, and the total grinding and polishing time is controlled to be more than 25 minutes to ensure a high-quality optical plane is obtained.

[0030] Preferably, when the volume ratio of the intergrowth to the target mineral is greater than 5% and less than or equal to 15%, f takes the value 1; when the volume ratio of the intergrowth to the target mineral is greater than 15% and less than or equal to 35%, f takes the value 2; when the volume ratio of the intergrowth to the target mineral is greater than 35%, f takes the value 3.

[0031] Compared with the prior art, the core technical advantages and beneficial effects of this invention are as follows:

[0032] This invention provides a novel method for evaluating the quality of flotation concentrates, which for the first time organically integrates economic indicators (grade, yield), chemical indicators (harmful impurities), and process mineralogical indicators (particle size, degree of liberation) to construct a comprehensive concentrate quality evaluation system. Through standardized processing and calculation of a comprehensive concentrate quality scoring index, multi-dimensional information is condensed into a quantifiable indicator, greatly reducing the bias of subjective experience-based judgments and making the evaluation results more scientific and objective.

[0033] The scoring items in the flotation concentrate quality evaluation method of this invention can directly serve production optimization. By analyzing the composition of the scoring items, bottleneck parameters affecting concentrate quality (such as insufficient liberation or poor particle size) can be quickly identified, thereby allowing for targeted adjustment of operating parameters in processes such as crushing, grinding, and beneficiation.

[0034] The weighting coefficients in the flotation concentrate quality evaluation method of this invention can be flexibly adjusted according to different ore types, beneficiation processes, and downstream demands, making the method widely applicable. For example, for concentrates directly fed into the furnace, the weighting of particle size and liberation can be increased; for chemically purified concentrates, more emphasis can be placed on grade and harmful impurities. Attached Figure Description

[0035] Figure 1 This is a polarizing microscope image of the concentrate product from Example 2.

[0036] Figure 2 This is a scanning electron microscope (SEM) energy dispersive spectroscopy (EDS) image of the elemental surface distribution of the raw ore in Example 3.

[0037] Figure 3 This is a measured image of the concentrate product from Example 3. Detailed Implementation

[0038] The technical concept of this invention lies in providing a method for evaluating the quality of concentrates, wherein the comprehensive quality index W of the concentrate is used to evaluate the concentrate:

[0039] W=T1-m T2+n T3+(mn) T4,

[0040] Where m is the rating coefficient for harmful impurities, with a value ranging from 0.05 to 0.30; n is the rating coefficient for particle size characteristics, with a value ranging from 0.01 to 0.20, and n is less than or equal to m. (mn) is the rating coefficient for dissociation characteristics.

[0041] T1=(hi R) / (Hi r);

[0042] T1 represents the basic grade score, reflecting the recovery efficiency and enrichment ratio of the target mineral. The higher this value, the higher the separation efficiency. i takes a natural number and refers to different target minerals. hi refers to the concentrate grade, r refers to the concentrate yield. R refers to the theoretical flotation yield of the concentrate, and Hi refers to the theoretical grade of the raw ore.

[0043] T2=r Σeg / ΣEg;

[0044] T2 represents the harmful impurity score; it reflects the enrichment degree of harmful elements, i.e., the adverse impact of harmful impurities on concentrate quality. The lower this value, the better. g takes a natural number and refers to different harmful elements. Eg refers to the content of harmful elements in the target mineral of the raw ore. eg refers to the content of harmful elements in the target mineral of the concentrate. m is sold as concentrate, with the harmful element loss accounting for more than 1% of the price. Considering actual processing costs and market fluctuations, a lower limit of 5% is taken.

[0045] T3=r di / Di;

[0046] T3 represents the particle size characteristic score. "di" refers to the content of the target mineral in the concentrate within a preset particle size range. "Di" refers to the content of the target mineral in the raw ore within a preset particle size range.

[0047] T4=r lij / Lij=r (∑ci li) / (∑Ci Li);

[0048] T4 represents the liberation characteristic score. T4 reflects the impact of liberation on flotation concentrate; a higher value is better. lij refers to the content of recoverable target minerals in the concentrate, and Lij refers to the content of recoverable target minerals in the raw ore. li refers to the degree of liberation of recoverable target minerals in the concentrate. Li refers to the degree of liberation of recoverable target minerals in the raw ore.

[0049] This invention provides a novel method for evaluating the quality of flotation concentrates, which for the first time organically integrates economic indicators (grade, yield), chemical indicators (harmful impurities), and process mineralogical indicators (particle size, degree of liberation) to construct a comprehensive concentrate quality evaluation system. Through standardized processing and calculation of a comprehensive concentrate quality scoring index, multi-dimensional information is condensed into a quantifiable indicator, greatly reducing the bias of subjective experience-based judgments and making the evaluation results more scientific and objective.

[0050] For the overall quality index W of concentrate:

[0051] 1. The higher the score, the better the concentrate quality. Empirically, a score of 80.00% or higher can be considered a concentrate with good indicators or good quality, while a score below 60.00% can be considered a concentrate with good indicators or poor quality.

[0052] 2. In particular, for the same sample, different reagent systems or processes are used to flotate different concentrates. This evaluation method can be used to determine the quality of different concentrates, so that different concentrates can be compared with each other under a comprehensive condition, and the best reagent system or beneficiation process can be selected.

[0053] The present invention will be further described in detail below with reference to specific embodiments, so that those skilled in the art can more clearly understand the present invention. The following embodiments are only used to illustrate the present invention, and are not intended to limit the scope of the present invention. Based on the specific embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of the present invention. In the embodiments of the present invention, unless otherwise specified, all raw material components are commercially available products well known to those skilled in the art; in the embodiments of the present invention, unless specifically specified, the technical means used are conventional means well known to those skilled in the art.

[0054] Example 1

[0055] This embodiment provides a method for evaluating the quality of iron ore flotation concentrate, including the following steps:

[0056] S1, Obtain raw ore samples and concentrate samples.

[0057] A representative raw ore sample was selected: a sedimentary metamorphic iron ore from the eastern Hebei region, belonging to a magnetite-hematite mixed ore. The current processing involves a deep or more complex ore body, where the magnetite has partially oxidized to hematite, forming a mixed ore. A combined process of "stage grinding-magnetic separation-flotation" was adopted. This embodiment only describes the reverse flotation stage, discussing the quality of flotation tailings (a special type of flotation concentrate) in the traditional sense. Grinding was carried out in a ball mill to a fineness of -200 mesh with a content of 85%.

[0058] Obtaining concentrate samples for evaluation: The laboratory flotation concentrate product is the concentrate obtained from the above-mentioned raw ore product through flotation. A conventional flotation process was adopted, with the following key conditions and parameters: pulp concentration 35%, NaOH addition 2.5 kg / t, starch addition 1200 g / t, pH adjustment 11.5, lime addition 800 g / t, and oxidized paraffin soap addition 700 g / t. The process involved one roughing step (8 min), followed by three cleaning and three scavenging steps.

[0059] S2, Preprocessing

[0060] The raw ore sample after ball milling and the concentrate sample to be evaluated were reduced to 4 g each. Samples of the same mass were prepared for automated mineralogical analysis. The specific process included:

[0061] Inlaying and Curing: Mix separately with epoxy resin liquid (commercial, key components: epoxy resin and curing agent, preferred application ratio 2:1, according to the instructions). Place in a mold and ultrasonically vibrate for 20 minutes to remove air bubbles, then heat to 60°C and cure for 1.5 hours to form an inlay block.

[0062] Grinding and polishing: The cured inserts are cross-cut and re-inserted to ensure flatness, and then ground and polished. Grinding uses 1000-grit and 2000-grit abrasives until the surface is smooth; polishing uses diamond polishing compound with a particle size of 0.5μm or smaller, and the total grinding and polishing time is controlled within 25 minutes to ensure a high-quality optical surface.

[0063] Carbon spraying treatment: The polished sample is placed in a vacuum coating instrument and a uniform carbon film is sprayed onto the surface to meet the conductivity requirements of automated mineralogy analysis.

[0064] S3, Mineralogical property testing

[0065] The raw ore samples and concentrate samples were tested and analyzed using an automated mineralogical analysis system (equipment model: MLA650, functional modules: material composition analysis, mineral composition analysis).

[0066] The content of the target mineral Ci, the content of the target element iron Ci' in the target mineral, the content of harmful elements Eg, the particle size distribution characteristics of the target mineral Di.d, and the proportion of the content of the target mineral in the liberated state Li.f are obtained in the raw ore sample.

[0067] In this context, i takes values ​​of 1 and 2 to represent magnetite and hematite, respectively, and g takes values ​​of 1 and 2 to represent the harmful elements phosphorus and sulfur, respectively.

[0068] The values ​​d, 1, 2, 3, 4, and 5, represent particle sizes greater than or equal to 0.120 mm, less than 0.120 mm but greater than or equal to 0.074 mm, less than 0.074 mm but greater than or equal to 0.037 mm, less than 0.037 mm but greater than or equal to 0.020 mm, and less than 0.020 mm, respectively.

[0069] The values ​​f = 1, 2, and 3 represent the single-member state, the rich intergrowth state, and the poor intergrowth state of the target mineral, respectively. f = 1 (single-member state): the volume ratio of intergrowth to target mineral is less than or equal to 5%; f = 2 (rich intergrowth): the volume ratio of intergrowth to target mineral is greater than or equal to 5% and less than or equal to 25%; f = 3 (poor intergrowth): the volume ratio of intergrowth to target mineral is greater than or equal to 25%.

[0070] The target mineral content (ci), harmful element content (eg), target mineral particle size distribution characteristics (di.d), target mineral liberation state content percentage (li.f), concentrate grade (hi) (64.12%), and concentrate yield (r) of the concentrate sample were obtained.

[0071] The statistical results are shown in the following table:

[0072] Detection and calculation results of raw ore samples

[0073]

[0074] Detection and calculation results of concentrate samples

[0075]

[0076] Main mineral particle size test results

[0077]

[0078] Calculate the theoretical grade Hi of the raw ore:

[0079] Hi=∑Ci Ci' / ∑Ci=(45.24%) 71.21% + 8.52% 69.88%) / (45.24%+8.52%)=71.00%.

[0080] The theoretical flotation yield R of the iron ore sample is: R = 45.24% + 8.52% = 53.76%.

[0081] Calculate the degree of liberation Li and the content of the recoverable target mineral Lij in the raw ore:

[0082] Li = Li.1 + Li.2,

[0083] Lij=∑Ci Li=45.24% 85.37% + 8.52% 79.67% = 45.41%.

[0084] Calculate the content Di of the target mineral with a particle size range of 0.020 mm to 0.120 mm:

[0085] Di=ΣCi Di.d=45.24% 85.30% + 8.52% 81.80% = 45.56%.

[0086] Calculate the degree of liberation of the recoverable target mineral li and the content of the recoverable target mineral lij in the concentrate:

[0087] li=K li.1+li.2, where K is the monomer recovery coefficient, with a value of 0.85;

[0088] lij=∑Ci li=88.64% (74.33%) (0.85 + 21.16%) + 4.17% (68.94%) (0.85 + 19.44%) = 78.01%.

[0089] Calculate the content di of target minerals in the concentrate with a particle size range of 0.020 mm to 0.120 mm:

[0090] di=Σci di.d = 88.64% 85.84% + 4.17% 83.53% = 79.57%.

[0091] Calculate the basic grade score T1:

[0092] T1=(hi R) / (Hi r)=(64.12% 53.76%) / (71.00%) 57.22%) = 84.85%.

[0093] Calculate the harmful impurity score T2:

[0094] T2=r Σeg / ΣEg=57.22% (0.092%+0.58%) / (0.065%+0.42%)=84.95%.

[0095] Calculate the granularity feature score T3:

[0096] T3=di r / Di = 79.57% 57.22% / 45.56%=99.93%.

[0097] Calculate the dissociation feature score T4:

[0098] T4=lij r / Lij=78.01% 57.22% / 45.41%=79.57%.

[0099] Calculate the overall quality index W of the concentrate, m=0.05, n=0.02:

[0100] W=T1-m T2+n T3+(mn) T4

[0101] =84.85% - 0.05 84.95% + 0.02 99.93% + 0.03 79.57%

[0102] =84.85% - 4.25% + 1.99% + 2.39%

[0103] =85.00%.

[0104] The overall quality index of this concentrate is 85.00%, with a basic score of 84.85%, indicating good recovery and yield control, and high separation efficiency. The harmful impurity score of 84.95% indicates poor impurity suppression, which will affect the concentrate's selling price and present some challenges for subsequent processing. The particle size score of 99.93% indicates that the concentrate recovered a significant amount of the target minerals within a reasonable particle size range. The liberation characteristic score of 79.57% indicates that the liberation during pre-flotation grinding is moderate, leaving room for further fine grinding. Overall, this concentrate is considered to be of good quality or with good flotation performance.

[0105] Example 2

[0106] This embodiment provides a method for evaluating the quality of primary copper ore flotation concentrate, including the following steps:

[0107] S1, Obtain raw ore samples and concentrate samples.

[0108] Representative raw ore samples were selected: These were from a primary copper ore mine in Hubei Province. The main target mineral for recovery from this ore was chalcopyrite, while other secondary copper sulfide and copper oxide minerals such as chalcocite were relatively scarce. The gangue minerals were mainly quartz and feldspar, with other mica and carbonate minerals being less abundant. The ore was ground in a ball mill to a fineness of -200 mesh with a content of 90%.

[0109] Obtaining the concentrate sample to be evaluated: The concentrate was obtained from laboratory flotation, specifically from the above-mentioned raw ore product. The flotation process parameters were as follows: pulp concentration 35%, lime addition 300 g / t; pH adjustment 11.5; sodium pentyl sulfonate addition 45 g / t; sulfur nitrogen No. 9 / ethyl sulfonate addition 2 g / t; MIBC addition 20 g / t; obtained using a closed-circuit flotation process consisting of one roughing stage, three scavenging stages (Z-200: 7 g / t), and three cleaning stages.

[0110] See Figure 1 Polarized light microscope images of the concentrate products show that the main metallic sulfides are pyrite and chalcopyrite.

[0111] S2, Preprocessing.

[0112] The method and steps are the same as in Example 1 above.

[0113] S3, Mineralogical property testing

[0114] The raw ore samples and concentrate samples were tested and analyzed using an automated mineralogical analysis system (equipment model: MLA650, functional modules: material composition analysis, mineral composition analysis).

[0115] The content of the target mineral Ci, the content of the target element Ci' in the target mineral, the content of harmful elements Eg, the particle size distribution characteristics of the target mineral Di.d, and the proportion of the content of the target mineral in the liberated state Li.f are obtained in the raw ore sample.

[0116] Where i takes the value 1 to represent chalcopyrite, and g takes the values ​​1 and 2 to represent the harmful elements arsenic and lead, respectively.

[0117] The values ​​d (1, 2, 3, 4, 5) represent particle sizes greater than or equal to 0.100 mm, less than 0.100 mm but greater than or equal to 0.074 mm, less than 0.074 mm but greater than or equal to 0.037 mm, less than 0.037 mm but greater than or equal to 0.010 mm, and less than 0.010 mm, respectively. The values ​​f (1, 2, 3) represent the single-membered state, the rich intergrowth state, and the poor intergrowth state of the target mineral, respectively.

[0118] The following parameters were obtained from the concentrate samples: target mineral content (ci), harmful element content (eg), target mineral particle size distribution characteristics (di.d), target mineral liberation state content percentage (li.f), concentrate grade (hi, 26.56%), and concentrate yield (r, 5.83%). The results are shown in the table below.

[0119] Test results of raw ore samples

[0120]

[0121] Test results of concentrate samples

[0122]

[0123] Main mineral particle size test results

[0124]

[0125] Calculate the theoretical grade Hi of the raw ore:

[0126] Hi=∑Ci Ci' / ∑Ci=4.42% 34.52% / 4.42%=34.52%.

[0127] Calculate the degree of liberation of the recoverable target mineral Li and the content of the recoverable target mineral Lij in the raw ore:

[0128] Li=Li.1+Li.2=89.63%+6.42%=96.05%.

[0129] Lij=∑Ci Li=4.42% 96.05% = 4.25%.

[0130] Calculate the content Di of the target mineral with a particle size range of 0.010 mm to 0.100 mm:

[0131] Di=ΣCi Di.d=4.42% 80.02% = 3.54%.

[0132] Calculate the degree of liberation of the recoverable target mineral li and the content of the recoverable target mineral lij in the concentrate:

[0133] li=K li.1+li.2, where K is the monomer recovery coefficient, with a value of 0.90;

[0134] lij=∑Ci li=76.94% (96.43%) (0.90 + 3.12%) = 69.17%.

[0135] Calculate the content di of target minerals in the concentrate with a particle size range of 0.010 mm to 0.100 mm:

[0136] di=Σci di.d = 76.94% 83.20% = 64.01%

[0137] The theoretical flotation yield of the concentrate, R, is calculated as follows: R = 4.42%.

[0138] Calculate the basic grade score T1:

[0139] T1=(hi R) / (Hi r)=(26.56% 4.42%) / (34.52%) 5.83%) = 58.33%.

[0140] Calculate the harmful impurity score T2:

[0141] T2=r Σeg / ΣEg=5.83% (0.016%+1.52%) / (0.04%+0.54%)=15.44%.

[0142] Calculate the granularity feature score T3:

[0143] T3=di r / Di = 64.01% 5.83% / 3.54%=105.42%.

[0144] Calculate the dissociation feature score T4:

[0145] T4=lij r / Lij=69.17% 5.83% / 4.25%=94.88%.

[0146] Calculate the comprehensive quality index W of the concentrate when m=0.10 and n=0.05:

[0147] W=T1-m T2+n T3+(mn)

[0148] =58.33% - 0.10 15.44% + 0.05 105.42% + 0.05 94.88%

[0149] =58.33% - 1.54% + 5.27% + 4.74%

[0150] =66.80%.

[0151] The overall quality index of this concentrate is 66.80%, with a basic score of 58.33%, indicating poor recovery and yield control, and low separation efficiency. The harmful impurity score is 15.44%, indicating good impurity suppression, minimal impact on the concentrate's selling price, and low difficulty in subsequent processing. The particle size score is 105.42%, indicating that the concentrate recovered more target minerals than expected within a reasonable particle size range. The liberation characteristic score is 94.88%, indicating good liberation during pre-flotation grinding. Overall, the quality of this concentrate is average.

[0152] Example 3

[0153] This embodiment provides a method for evaluating the quality of flotation concentrate from lead-zinc polymetallic ores, comprising the following steps:

[0154] S1, Obtain raw ore samples and concentrate samples.

[0155] Representative raw ore samples were selected: These were from a copper-lead-zinc polymetallic ore sourced in Jiangxi Province. The ore is primarily a copper-lead-zinc polymetallic ore, with galena as the main target mineral for recovery. Lead exhibits some degree of oxidation, with cerussite as the oxidized mineral. Zinc and copper minerals are relatively scarce. Only the quality evaluation of the lead concentrate from lead-zinc separation is described. Grinding was performed in a ball mill to a fineness of -200 mesh, with a content of 80%.

[0156] Obtaining concentrate samples for evaluation: These were obtained from laboratory flotation concentrates, specifically the concentrates obtained from the above-mentioned raw ore products through flotation. Key flotation parameters were as follows: Sulfur-oxygen flotation was employed separately. The pulp concentration was 30%. 1. Galena flotation: Lime adjustment, pH adjusted to 9.5; zinc sulfate to sodium sulfite ratio 1:1, total dosage 700 g / t; ethyl thiocyanate dosage 40 g / t; MIBC dosage 10 g / t; 2. Lead oxide mineral flotation: pH adjusted to 8.5; sodium sulfide dosage 2000 g / t; sodium pentyl jaundice 70 g / t; 3. The above samples were combined and further refined: refmilled to a 325 mesh content of 95%; obtained through three refining processes and two scavenging processes.

[0157] See Figure 2 and Figure 3 The elemental distribution of the raw ore under scanning electron microscopy (SEM) energy dispersive spectroscopy (EDS) is as follows: Pb-galena, Pb / O-lead oxide, O-gangue. The SEM energy dispersive spectroscopy distribution map shows the distribution characteristics of galena [blue] and lead oxide [gray].

[0158] S2, Preprocessing. Same as the method and steps in Example 1 above.

[0159] S3, Mineralogical property testing

[0160] The raw ore samples and concentrate samples were tested and analyzed using an automated mineralogical analysis system (equipment model: MLA650, functional modules: material composition analysis, mineral composition analysis).

[0161] The content of the target mineral Ci, the content of the target element Ci' in the target mineral, the content of harmful elements Eg, the particle size distribution characteristics of the target mineral Di.d, and the proportion of the content of the target mineral in the liberated state Li.f are obtained in the raw ore sample.

[0162] Where i takes values ​​of 1 and 2 to represent galena and cerussite, respectively, and g takes a value of 1 to represent the harmful element zinc. d takes values ​​of 1, 2, 3, 4, and 5 to represent particle sizes greater than or equal to 0.100 mm, less than 0.100 mm but greater than or equal to 0.074 mm, less than 0.074 mm but greater than or equal to 0.037 mm, less than 0.037 mm but greater than or equal to 0.010 mm, and less than 0.010 mm, respectively. f takes values ​​of 1, 2, and 3 to represent the single-member state, rich intergrowth state, and poor intergrowth state of the target mineral, respectively. f=1 (single-member state): the volume ratio of intergrowth to target mineral is less than or equal to 5%; f=2 (rich intergrowth): the volume ratio of intergrowth to target mineral is greater than or equal to 5% and less than or equal to 25%; f=3 (poor intergrowth): the volume ratio of intergrowth to target mineral is greater than or equal to 25%.

[0163] The target mineral content (ci), harmful element content (eg), target mineral particle size distribution characteristics (di.d), target mineral liberation state content percentage (li.f), concentrate grade (hi) (50.85%), and concentrate yield (r) of the concentrate sample were obtained.

[0164] The statistical results are shown in the table below:

[0165] Test results of raw ore samples

[0166]

[0167] Test results of concentrate samples

[0168]

[0169] Main mineral particle size test results

[0170]

[0171] Calculate the theoretical grade Hi of the raw ore:

[0172] Hi=∑Ci Ci' / ∑Ci=(3.52%) 86.61% + 1.20% 77.49%) / (3.52%+1.20%)=84.29%.

[0173] Calculate the degree of liberation of the recoverable target mineral Li and the content of the recoverable target mineral Lij in the raw ore:

[0174] Li = Li.1 + Li.2,

[0175] Lij=∑Ci Li=3.52% 92.63% + 1.20% 89.86% = 4.34%.

[0176] Calculate the content Di of the target mineral with a particle size range of 0.010 mm to 0.100 mm:

[0177] Di=ΣCi Di.d=3.52% 58.60% + 1.20% 65.63% = 2.85%.

[0178] Calculate the degree of liberation of the recoverable target mineral li and the content of the recoverable target mineral lij in the concentrate:

[0179] li=K li.1+li.2, where K is the monomer recovery coefficient, with a value of 0.85;

[0180] lij=∑Ci Li'

[0181] =53.44% (91.97%) (0.85 + 4.26%) + 5.89% (57.51%) (0.85 + 35.68%) = 49.03%.

[0182] Calculate the content di of target minerals in the concentrate with a particle size range of 0.010 mm to 0.100 mm:

[0183] di=Σci di.d = 53.44% 81.99% + 5.89% 78.98% = 48.47%.

[0184] Calculate the theoretical flotation yield R of the concentrate:

[0185] R = 3.52% + 1.20% = 4.72%.

[0186] Calculate the basic grade score T1:

[0187] T1=(hi R) / (Hi r)=(50.85% 4.72%) / (84.29%) 6.31%) = 45.13%.

[0188] Calculate the harmful impurity score T2:

[0189] T2=r Σeg / ΣEg=6.31% 1.41% / 0.22%=40.44%.

[0190] Calculate the granularity feature score T3:

[0191] T3=di r / Di = 6.31% 48.47% / 2.85%=107.31%.

[0192] Calculate the dissociation feature score T4:

[0193] T4=li r / Li = 49.03% 6.31% / 4.34%=71.29%.

[0194] Calculate the overall quality index W of the concentrate, m=0.10, n=0.05:

[0195] W=T1-m T2+n T3+(mn)

[0196] =45.13% - 0.10 40.44% + 0.05 107.31% + 0.05 71.29% = 45.13% - 4.04% + 5.37% + 3.56%

[0197] =50.02%.

[0198] The overall quality index of this concentrate is 55.02%, with a basic score of 45.13%, indicating poor recovery and yield control, and very low separation efficiency. The harmful impurity score is 40.44%, indicating good impurity suppression in the concentrate, minimal impact on the selling price, and low difficulty in subsequent processing. The particle size score is 107.31%, indicating that the concentrate recovered more than expected target minerals within a reasonable particle size range. The liberation characteristic score is 71.29%, indicating that the liberation during pre-flotation grinding is only average, with room for finer grinding. Overall, the quality of this concentrate is poor.

[0199] It should be noted that the above embodiments are only for further elaboration and explanation of the technical solution of the present invention, and are not intended to further limit the technical solution of the present invention. The method of the present invention is only a preferred embodiment and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for evaluating the quality of a flotation concentrate, characterized in that The method comprises the following steps: obtaining an ore sample and a concentrate sample; sampling, embedding and curing, grinding and polishing, carbon spraying treatment, and automatic mineralogical analysis are performed respectively; obtaining the content Ci of target minerals in the ore sample, the content Ci' of target elements in the target minerals, the content Eg of harmful elements, the particle size distribution characteristics Di.d of the target minerals, and the content proportion Li.f of the dissociation state of the target minerals, wherein i is a natural number and represents different target minerals, g is a natural number and represents different harmful elements, d is a natural number and represents different particle size ranges, and f is 1, 2 or 3, representing the monomer state, the rich intergrowth state and the poor intergrowth state of the target minerals respectively; Calculating the theoretical grade of raw ore Hi: Hi =∑Ci Ci’ / ∑Ci, calculating the dissociation degree Li of the recoverable target minerals in the ore: Li = Li.1 + Li.2, calculating the content Di of the target mineral in the preset particle size range interval: Di =∑Ci Di.d, obtaining the content ci of target minerals, the content eg of harmful elements, the particle size distribution characteristics di.d of the target minerals, the content proportion li.f of the dissociation state of the target minerals, the concentrate grade hi and the concentrate yield r of the concentrate sample, calculating the dissociation degree li of the recoverable target minerals in the concentrate: li = K li.1 + li.2, K is a monomer recovery coefficient with a value of 0.50-1.00; Calculating the content of the recoverable target mineral Lijin the raw ore =∑Ci Li; calculating the content of the recoverable target mineral in the concentrate lij=∑ci li; Calculating the content di of the target mineral particle size range in the preset particle size range interval of the concentrate: di =∑ci di.d, calculating the theoretical flotation yield R of the concentrate: R = ∑Ci; calculating the comprehensive quality index W of the concentrate: W = T1-m T2+n T3+(m-n) T4=(hi R) / (Hi r)-m r Σeg / ΣEg+n di r / Di+(m-n) lij r / Lij, m is 0.05~0.30, n is 0.01~0.20, and n≤m; where T1 = (hi R) / (Hi r) ; T2 = r Σeg / Σeg; T3 = r di / Di; T4 = r lij / Lij = r (∑ci li) / (∑Ci Li).

2. The method of evaluating the quality of a floatation concentrate according to claim 1, characterized in that, The method further comprises a step of ball milling pretreatment of the ore sample, and the grinding fineness is 65-95% of -200 mesh content.

3. The method of evaluating the quality of a floatation concentrate according to claim 1, characterized in that, The sampling mass is 3-5 g.

4. The method of evaluating the quality of a floatation concentrate according to claim 1, characterized in that, The embedding and curing adopt an epoxy resin curing system.

5. The method for evaluating the quality of a flotation concentrate according to any one of claims 1 to 4, characterized in that, When the volume ratio of intergrowth to target minerals is greater than 5% and less than or equal to 15%, f is 1; When the volume ratio of intergrowth to target minerals is greater than 15% and less than or equal to 35%, f is 2; When the volume ratio of intergrowth to target minerals is greater than 35%, f is 3.

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