Method for measuring content of metal sulfide

Abstract

The invention provides a method for measuring the content of metal sulfide, and belongs to the technical field of process mineralogy. The method for measuring the content of the metal sulfide comprises the following steps: grinding ore, analyzing a sulfur phase, carrying out reselection and acid treatment on a sample subjected to ore grinding, respectively carrying out sulfur phase analysis and automatic mineralogy analysis on the sample subjected to acid treatment, and finally carrying out test analysis to obtain the content of the metal sulfide. According to the method, sulfur phase analysis is performed on the samples subjected to ore grinding and reselection and acid treatment enrichment, automatic mineralogical analysis is performed on the samples subjected to reselection and acid treatment enrichment, amplified data is corrected into data of original samples, accurate measurement of the content of the low-content metal sulfide is achieved, and the accuracy of measurement of the content of the low-content metal sulfide is improved. And through automatic mineralogical analysis, the contents of different metal sulfides can be respectively measured. The test method provided by the invention is accurate in data measurement, reduces interference of human subjective factors to a great extent, and provides reliable data support for efficient utilization of stone resources.

Description

Technical Field

[0001] The invention relates to the technical field of process mineralogy, and in particular to a method for determining the content of metal sulfide. Background Art

[0002] Primary sulfide mineral resources are an important part of natural resources. A large part of the minerals we use now come from these metal sulfides. In process mineralogy research, the measurement of metal sulfide content is an important data for evaluating ore quality and determining its industrial value. However, the measurement of low-content metal sulfides faces many difficulties, especially when the metal sulfide content is below a certain threshold, the measurement accuracy and reliability are often significantly affected.

[0003] Existing testing methods are mainly divided into chemical analysis and instrumental measurement. Chemical analysis methods are often interfered by reducing substances such as thiosulfate and sulfite, which react with the measuring reagents, resulting in high or low measurement results. In addition, sampling representativeness, suspended matter, color, turbidity and some heavy metal ions in the sample will also interfere with the measurement. Instrumental analysis includes a variety of technologies, such as spectral analysis, chromatography, mass spectrometry, electrochemical analysis, etc. Each technology has its own unique principles and application range, but when measuring low-content metal sulfide samples, due to the low mineral content, there will be large errors, because instrumental measurement mainly scans a large number of mineral particles on the sample, and then statistically analyzes and calculates its content. The number of low-content metal sulfide particles is relatively small, and the probability of detection is also low. The data fluctuations caused are also significant, which is easy to cause errors.

[0004] In the prior art, a patent with publication number CN 118225988 B provides a method for calculating the oxidation rate of gold ore and its application. The calculation method introduces the measurement and analysis of the oxidation degree of carrier minerals, and combines automatic mineralogical analysis and the determination of gold grade through gravity separation process. Through the combination of the above three technical means, the gold ore sample to be tested is respectively analyzed for the gold content of the main metal sulfide, the content of the main metal sulfide and the main metal oxide, and the gold grade are determined, so as to realize the correction calculation of the oxidation rate of the gold ore, thereby obtaining an accurate theoretical oxidation rate of the gold ore. This invention is mainly aimed at a certain sulfide content. When the sulfide content is very low, the automatic mineralogical analysis data will have a certain error. The patent with publication number CN 109975384 B provides a method for detecting the metal distribution rate in rocks, including: preparing a light sheet, a thin sheet or a probe sheet of a rock sample, and then coating it; using a mineralogy automatic analysis instrument to measure the mass percentage of minerals in the rock; using a laser ablation inductively coupled plasma mass spectrometer to measure the mass content of the metal element M in the mineral, in units of ppm; calculating the grade of the metal element M in the rock according to formula 1, which is: the grade of the metal element M in the rock = (∑γi×βi×10 -4 )×100%, i=1, 2, ..., n, where i represents the i-th mineral in the rock, γi represents the mass percentage of the i-th mineral in the rock, and βi represents the mass content (ppm) of the metal element M in the i-th mineral; the metal distribution rate of the metal element M in the rock is calculated according to Formula 2, which is: the metal distribution rate of the metal element M in the i-th mineral = (γi×βi×10 -4 ÷ the grade of rubidium in the rock) × 100%. This invention is a method for calculating the element content in a sample based on the measured mineral content and the element content in the ore. However, it is difficult to accurately measure low-content minerals. Summary of the invention

[0005] In view of the technical problems existing in the background technology, the present application provides a method for determining the content of metal sulfide, aiming to solve the problem that the existing metal sulfide content testing method is difficult to accurately measure low-content metal sulfide and cannot measure the content of different metal sulfides separately.

[0006] The present application provides a method for determining the content of metal sulfide, comprising the following steps: S1. Take the sample to be tested, grind it, and obtain a ground sample; S2. uniformly sampling the ground sample, performing a first sulfur phase analysis, and measuring the mass fraction of sulfur in the metal sulfide to the total mass of the ground sample as C11; S3. Re-select the sample after grinding to obtain a gravity-selected concentrate J1 and a gravity-selected tailing W1; S4. The gravity separation tailings W1 are treated with acid, then washed, filtered, and dried to obtain a sample W2; S5. Mixing the gravity separation concentrate J1 and sample W2 to obtain sample J12; S6. uniformly sample the sample J12, perform a second sulfur phase analysis, and measure the mass fraction of sulfur in the metal sulfide to the total mass of the sample J12 to be C22; S7. Sampling the sample J12 and preparing the sample J13 for automatic mineralogical analysis; S8. Perform automatic mineralogical analysis on the sample J13, and measure the sum of the horizontal projection lengths of the cross sections of various metal sulfides and the sulfur content of various metal sulfides, wherein the sum of the horizontal projection lengths of the cross sections of the i-th metal sulfide is recorded as Li, and the sulfur content of the i-th metal sulfide is recorded as Si; Li= , Lim represents the horizontal projection length of the cross section of the mth mineral grain in the i-th metal sulfide, i=1, 2, ..., n, n is the total number of types of metal sulfides measured, m=1, 2, 3, ..., N, N is the total number of mineral grains of the i-th metal sulfide; S9. Calculate the content of each metal sulfide in the sample J13, wherein the content of the i-th metal sulfide is recorded as Mi', Mi'=ρi*Di*X, ​​and Ci=Mi'*Si, C22= ; where ρi is the density of the i-th metal sulfide; Di is the volume fraction of the i-th metal sulfide, Di=Li / ; X is the conversion coefficient; Ci is the mass fraction of the mass of sulfur in the i-th metal sulfide to the total mass of the sample J13; S10. Calculate the content of each metal sulfide in the original sample, wherein the content of the i-th metal sulfide in the original sample is recorded as Mi, then Mi=Mi'*C11 / C22.

[0007] In the technical solution of the embodiment of the present application, the present application respectively performs sulfur phase analysis on samples after grinding and after gravity separation and acid treatment enrichment, and performs automatic mineralogical analysis on samples after gravity separation and acid treatment enrichment, and corrects the amplified data back to the data of the original sample, thereby realizing accurate measurement of the content of low-content metal sulfides, and through automatic mineralogical analysis, the content of different metal sulfides can be measured respectively. The test method provided by the present invention measures data accurately, greatly reduces the interference of human subjective factors, saves manpower, and provides reliable data support for the efficient use of such stone resources.

[0008] In some embodiments, in step S1, the grinding fineness is -0.074 mm and the content is 75%~95%.

[0009] In this embodiment, the sample to be tested is ground to a certain fineness to facilitate the subsequent processing of the sample.

[0010] In some embodiments, in step S2, the first sulfur phase analysis includes: using a differential method or an acetic acid-hydrogen peroxide leaching method to measure the mass fraction of the mass of sulfur in the metal sulfide in the post-grinding sample to the total mass of the post-grinding sample.

[0011] In this embodiment, the mass fraction of the mass of sulfur in the metal sulfide in the ground sample to the total mass of the ground sample is measured, and finally converted to obtain the content of the metal sulfide in the original sample.

[0012] In some embodiments, in step S3, the gravity separation adopts a heavy liquid stirring separation method, and the gravity separation reagent is a mixture of thallium formate and thallium malonate in aqueous solution.

[0013] In this embodiment, the metal sulfides in the ore sample are enriched by gravity separation.

[0014] In some embodiments, in step S4, the acid in the acid treatment includes hydrofluoric acid and sulfuric acid, the temperature of the acid treatment is 90-95° C. in a water bath, and the time of the acid treatment is 22-26 hours.

[0015] In this embodiment, by treating with hydrofluoric acid and sulfuric acid, the gangue, quartz, carbonate minerals, mica minerals and pyroxene minerals in the ore sample can be dissolved, while the metal sulfides are retained, and the metal sulfides are further enriched.

[0016] In some embodiments, in step S7, the process of preparing the sample for automatic mineralogical analysis comprises: S71. The sample J12 is mixed with a thermosetting inlay material in a volume ratio of 1:0.5 to 1:3, and cured in an inlay machine at a temperature of 100 to 150°C and a pressure of 200 to 300 Bar; the thermosetting inlay material is a thermosetting phenolic epoxy resin, and the particle size of the thermosetting inlay material is not greater than 38 μm; S72. Grind and polish the solidified sample and perform carbon spraying. In the grinding and polishing, the sizes of the abrasives include 150 μm, 23 μm and 13 μm, and the grinding time is 8 to 10 min. The sizes of the polishing materials include 6 μm, 3 μm and 1 μm, and the polishing time is 8 to 10 min. The carbon spraying method is ion sputtering, and the thickness of the carbon spraying is 5 to 10 nm.

[0017] In this embodiment, the enriched metal sulfide is prepared into an automatic mineralogical analysis sample, and then the automatic mineralogical analysis is performed.

[0018] In some embodiments, in step S6, the second sulfur phase analysis includes: using a differential method or an acetic acid-hydrogen peroxide leaching method to measure the mass fraction of the mass of sulfur in the metal sulfide in the sample J12 to the total mass of the sample J12.

[0019] In this embodiment, a second sulfur phase analysis is performed on the enriched ore sample to obtain the mass fraction of the mass of sulfur in the metal sulfide in the sample J12 to the total mass of the sample J12 taken, and the mass fraction of the mass of sulfur in the metal sulfide in the amplified ore sample to the total mass of the sample J12 taken is obtained. Finally, combined with other data, the content of metal sulfide in the original sample is obtained.

[0020] In some embodiments, in step S8, the magnification of the automatic mineralogical analysis test is 300-1000 times, and the number of particles tested is 30,000-50,000.

[0021] In this embodiment, relatively fine particles can be detected by magnifying the automatic mineralogical analysis test to a certain multiple; by detecting a certain number of particles, the test data is made more representative.

[0022] In some embodiments, in step S8, the horizontal projection length of the cross section of the i-th metal sulfide refers to the horizontal maximum intercept of the mineral particle leakage surface of the i-th metal sulfide.

[0023] In this embodiment, the ratio of the maximum horizontal intercepts of the particle exposure surface is used as the ratio of the particle volume through automatic mineralogical analysis. Compared with the traditional method of adding a ruler to a microscope to measure the ratio of the intercept lengths of a series of parallel straight lines of the particles passing through each mineral, which is equal to the volume ratio of each mineral, it is more convenient and more suitable for detection by automatic mineralogical analysis instruments, and greatly reduces the influence of human subjective factors.

[0024] In some embodiments, in step S8, the sulfur content Si of the i-th metal sulfide is an average value of the sulfur content measurement results of at least 10 mineral particles of the i-th metal sulfide.

[0025] In this embodiment, the sulfur content of the enriched metal sulfide is measured by automatic mineralogical analysis to obtain the amplified sulfur content of the metal sulfide. Finally, the sulfur content of the metal sulfide in the original ore sample can be converted by combining other data.

[0026] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solution of the present application, the following is a brief introduction to the drawings used in the present application. Obviously, the drawings described below are only some embodiments of the present application, and for ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0028] Figure 1 This is a flow chart of the method for determining the metal sulfide content in Example 1.

[0029] Figure 2 This is an automatic mineralogical analysis test chart of pyrite (red particles) in the method for determining the metal sulfide content in Example 1.

[0030] Figure 3 This is a horizontal projection length test diagram of the cross section of pyrite (red particles) in the method for determining the metal sulfide content in Example 1. DETAILED DESCRIPTION

[0031] The following is a detailed description of the embodiments of the technical solution of the present application. The following embodiments are only used to more clearly illustrate the technical solution of the present application, and are therefore only used as examples, and cannot be used to limit the scope of protection of the present application.

[0032] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0033] In the description of the embodiments of the present application, technical terms such as "first" and "second" are only used to distinguish different objects and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features.

[0034] In the description of the embodiments of the present application, the term "and / or" is only a description of the association relationship of the associated objects, indicating that there may be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0035] In order to solve the problem that the existing method for determining the content of metal sulfide is not accurate enough for the test results of low-content metal sulfide, and the content of different metal sulfides cannot be measured separately, the present application provides a method for determining the content of metal sulfide. By performing sulfide phase analysis on the samples after grinding and after gravity separation and acid treatment enrichment, and performing automatic mineralogical analysis on the samples after gravity separation and acid treatment enrichment, the amplified data is corrected back to the data of the original sample, so as to achieve accurate measurement of the content of low-content metal sulfide, and the content of different metal sulfides can be measured separately through automatic mineralogical analysis. In addition, when testing the volume ratio of the particles, the ratio of the horizontal maximum intercept of the particle appearance surface is used as the ratio of the volume of the particles. Compared with the traditional method of adding a scale to a microscope, measuring the intercept length ratio of each mineral by a series of parallel straight lines of the particles, which is equal to the volume ratio of each mineral, the method is more convenient, more suitable for automatic mineralogical analysis instrument detection, and greatly reduces the influence of human subjective factors. The test method provided by the present invention measures data accurately, greatly reduces the interference of human subjective factors, saves manpower, and provides reliable data support for the efficient use of such stone resources.

[0036] The present application provides a method for determining the content of metal sulfide, comprising the following steps: S1. Take the sample to be tested, grind it, and obtain a ground sample; S2. uniformly sampling the ground sample, performing a first sulfur phase analysis, and measuring the mass fraction of sulfur in the metal sulfide to the total mass of the ground sample as C11; S3. Re-select the sample after grinding to obtain a gravity-selected concentrate J1 and a gravity-selected tailing W1; S4. The gravity separation tailings W1 are treated with acid, then washed, filtered, and dried to obtain a sample W2; S5. Mixing the gravity separation concentrate J1 and sample W2 to obtain sample J12; S6. uniformly sample the sample J12, perform a second sulfur phase analysis, and measure the mass fraction of sulfur in the metal sulfide to the total mass of the sample J12 to be C22; S7. Sampling the sample J12 and preparing the sample J13 for automatic mineralogical analysis; S8. Perform automatic mineralogical analysis on the sample J13, and measure the sum of the horizontal projection lengths of the cross sections of various metal sulfides and the sulfur content of various metal sulfides, wherein the sum of the horizontal projection lengths of the cross sections of the i-th metal sulfide is recorded as Li, and the sulfur content of the i-th metal sulfide is recorded as Si; Li= , Lim represents the horizontal projection length of the cross section of the mth mineral grain in the i-th metal sulfide, i=1, 2, ..., n, n is the total number of types of metal sulfides measured, m=1, 2, 3, ..., N, N is the total number of mineral grains of the i-th metal sulfide; S9. Calculate the content of each metal sulfide in the sample J13, wherein the content of the i-th metal sulfide is recorded as Mi', Mi'=ρi*Di*X, ​​and Ci=Mi'*Si, C22= ; where ρi is the density of the i-th metal sulfide; Di is the volume fraction of the i-th metal sulfide, Di=Li / ; X is the conversion coefficient; Ci is the mass fraction of the mass of sulfur in the i-th metal sulfide to the total mass of the sample J13; S10. Calculate the content of each metal sulfide in the original sample, wherein the content of the i-th metal sulfide in the original sample is recorded as Mi, then Mi=Mi'*C11 / C22.

[0037] In the technical solution of the embodiment of the present application, by performing sulfur phase analysis on samples after grinding and after gravity separation and acid treatment enrichment, and performing automatic mineralogical analysis on samples after gravity separation and acid treatment enrichment, the amplified data is corrected back to the data of the original sample, so as to achieve accurate measurement of the content of low-content metal sulfides, and the content of different metal sulfides can be measured respectively through automatic mineralogical analysis. The test method provided by the present invention measures data accurately, greatly reduces the interference of human subjective factors, saves manpower, and provides reliable data support for the efficient use of such stone resources.

[0038] Furthermore, in some embodiments, in step S1, the grinding fineness is -0.074 mm and the content is 75% to 95%.

[0039] In the technical solution of the embodiment of the present application, by grinding the sample to be tested to a certain fineness, it is convenient for the subsequent processing of the sample.

[0040] Furthermore, in some embodiments, in step S2, the first sulfur phase analysis includes: using a differential method or an acetic acid-hydrogen peroxide leaching method to measure the mass fraction of the mass of sulfur in the metal sulfide in the post-grinding sample to the total mass of the post-grinding sample.

[0041] In the technical solution of the embodiment of the present application, the mass fraction of sulfur in the metal sulfide in the ground sample to the total mass of the ground sample is measured, and finally the content of metal sulfide in the original sample is obtained by conversion.

[0042] Furthermore, in some embodiments, the difference method refers to the amount obtained by subtracting the amount of sulfur in natural sulfur and sulfate from the total sulfur amount. The detection of the total sulfur amount refers to GB / T7739.8-2007, and the detection of sulfur in natural sulfur and sulfate refers to "Application of Sulfur Phase Analysis and Determination Method"; the acetic acid-hydrogen peroxide leaching method refers to "Application of Sulfur Phase Analysis and Determination Method".

[0043] Furthermore, in some embodiments, in step S3, the gravity separation adopts a heavy liquid stirring separation method, and the gravity separation reagent is an aqueous solution mixture of thallium formate and thallium malonate; preferably, the mass ratio of thallium formate, thallium malonate and water is 7:7:1~2.

[0044] In the technical solution of the embodiment of the present application, the metal sulfides in the ore sample are enriched by gravity separation.

[0045] Furthermore, in some embodiments, in step S4, the acid in the acid treatment includes hydrofluoric acid and sulfuric acid, the temperature of the acid treatment is 90-95°C in a water bath, and the time of the acid treatment is 22-26h; preferably, the hydrofluoric acid is analytically pure, the concentration of sulfuric acid is 10%, and the volume ratio of hydrofluoric acid to sulfuric acid is 1:1; the solid-liquid ratio of the gravity separation tailings W1 to the acid is 1:4.

[0046] In the technical solution of the embodiment of the present application, by treating with hydrofluoric acid and sulfuric acid, the gangue, quartz, carbonate minerals, mica minerals and pyroxene minerals in the ore sample can be dissolved, while the metal sulfides are retained, and the metal sulfides are further enriched.

[0047] Further, in some embodiments, in step S7, the automatic mineralogical analysis sample preparation process includes: S71. The sample J12 is mixed with a thermosetting inlay material in a volume ratio of 1:0.5 to 1:3, and cured in an inlay machine at a temperature of 100 to 150°C and a pressure of 200 to 300 Bar; the thermosetting inlay material is a thermosetting phenolic epoxy resin, and the particle size of the thermosetting inlay material is not greater than 38 μm; S72. Grind and polish the solidified sample and perform carbon spraying. In the grinding and polishing, the sizes of the abrasives include 150 μm, 23 μm and 13 μm, and the grinding time is 8 to 10 min. The sizes of the polishing materials include 6 μm, 3 μm and 1 μm, and the polishing time is 8 to 10 min. The carbon spraying method is ion sputtering, and the thickness of the carbon spraying is 5 to 10 nm.

[0048] In the technical solution of the embodiment of the present application, the enriched metal sulfides are prepared into automatic mineralogical analysis samples, and then the automatic mineralogical analysis is carried out.

[0049] Furthermore, in some embodiments, in step S6, the second sulfur phase analysis includes: using a differential method or an acetic acid-hydrogen peroxide leaching method to measure the mass fraction of the mass of sulfur in the metal sulfide in the sample J12 to the total mass of the sample J12.

[0050] In the technical solution of the embodiment of the present application, a second sulfur phase analysis is performed on the enriched ore sample to obtain the mass fraction of the mass of sulfur in the metal sulfide in the sample J12 to the total mass of the sample J12 taken, and the mass fraction of the mass of sulfur in the metal sulfide in the amplified ore sample to the total mass of the sample J12 taken is obtained. Finally, combined with other data, the content of metal sulfide in the original sample is obtained.

[0051] Furthermore, in some embodiments, the difference method refers to the amount obtained by subtracting the amount of sulfur in natural sulfur and sulfate from the total sulfur amount. The detection of the total sulfur amount refers to GB / T7739.8-2007, and the detection of sulfur in natural sulfur and sulfate refers to "Application of Sulfur Phase Analysis and Determination Method"; the acetic acid-hydrogen peroxide leaching method refers to "Application of Sulfur Phase Analysis and Determination Method".

[0052] Furthermore, in some embodiments, in step S8, the magnification of the automatic mineralogical analysis test is 300-1000 times, and the number of particles tested is 30,000-50,000.

[0053] In the technical solution of the embodiment of the present application, relatively fine particles can be detected by magnifying the automatic mineralogical analysis test to a certain multiple; by detecting a certain number of particles, the test data is made more representative.

[0054] Furthermore, in some embodiments, in step S8, the horizontal projection length of the cross section of the i-th metal sulfide refers to the horizontal maximum intercept of the mineral particle leakage surface of the i-th metal sulfide.

[0055] In the technical solution of the embodiment of the present application, the ratio of the maximum horizontal intercepts of the particle exposure surface is used as the ratio of the particle volume through automatic mineralogical analysis. Compared with the traditional method of adding a ruler to a microscope to measure the ratio of the intercept lengths of a series of parallel straight lines of the particles passing through each mineral, which is equal to the volume ratio of each mineral, the method is more convenient and more suitable for detection by automatic mineralogical analysis instruments, and greatly reduces the influence of human subjective factors.

[0056] Furthermore, in some embodiments, in step S8, the sulfur content Si of the i-th metal sulfide is an average value of the sulfur content measurement results of at least 10 mineral particles of the i-th metal sulfide.

[0057] In the technical solution of the embodiment of the present application, the sulfur content of the enriched metal sulfide is measured by automatic mineralogical analysis to obtain the amplified sulfur content of the metal sulfide. Finally, the sulfur content of the metal sulfide in the original ore sample can be converted by combining other data.

[0058] Some specific embodiments are listed below. It should be noted that the embodiments described below are exemplary and are only used to explain the present application, and should not be construed as limiting the present application. If specific techniques or conditions are not specified in the embodiments, the techniques or conditions described in the literature in this area or the product specifications are used. The reagents or instruments used without specifying the manufacturer are all conventional products that can be obtained commercially.

[0059] Example 1 This embodiment provides a method for determining the content of metal sulfide, such as Figure 1 As shown, the specific steps include: (1) Weigh 1000g of the sample to be tested, the grinding fineness is -0.074mm and the content is 85%.

[0060] (2) Weigh 5 g of the ground sample and use the "Application of Sulfur Phase Analysis Method" to measure the mass fraction of sulfur in the metal sulfide to the total mass of the ground sample. The mass fraction is C11 = 0.244%.

[0061] (3) Weigh 500 g of the sample after grinding and perform gravity separation by heavy liquid stirring separation method to obtain gravity separation concentrate J1 and gravity separation tailings W1. The gravity separation reagent is a mixed solution of thallium formate: thallium malonate: water in a mass ratio of 7:7:1.

[0062] (4) Prepare 1000 mL of a mixture of analytical pure hydrofluoric acid and 10% sulfuric acid in a volume ratio of 1:1, add it to the gravity separation tailings W1, treat it in a 90°C water bath for 25 h, then wash, filter, and dry to obtain sample W2.

[0063] (5) The gravity separation concentrate J1 and sample W2 are mixed to obtain sample J12.

[0064] (6) Weigh 5 g of sample J12 and use the “Application of Sulfur Phase Analysis Method” to measure the mass fraction of sulfur in the metal sulfide in the total mass of sample J12 to obtain C22 = 25.622%.

[0065] (7) Preparation of samples for automatic mineralogical analysis: Sample J12 was mixed with a thermosetting phenolic epoxy resin with a particle size of 400 mesh at a volume ratio of 1:3, and cured in a mounting machine at a temperature of 150°C and a pressure of 200 Bar; the cured sample was ground, polished and carbon-sprayed to obtain sample J13; the sizes of the grinding materials were 150 μm, 23 μm and 13 μm, and the grinding took 8 min; the sizes of the polishing materials were 6 μm, 3 μm and 1 μm, and the polishing took 8 min; the carbon spraying method was ion sputtering, and the carbon spraying thickness was 5 nm.

[0066] (8) Sample J13 was subjected to automatic mineralogical analysis. The magnification of the automatic mineralogical analysis instrument was adjusted to 800 times. The sum of the horizontal projection lengths Li of the cross section of a certain metal sulfide in 50,000 samples and the sulfur content Si, Li= of a certain metal sulfide were measured. , Lim represents the horizontal projection length of the cross section of the mth mineral grain in the i-th metal sulfide, i=1, 2, ..., n, n is the total number of types of metal sulfides measured, m=1, 2, 3, ..., N, N is the total number of mineral grains of the i-th metal sulfide; in this embodiment, the mineral contains two kinds of metal sulfides, when i=1, it is pyrite, when i=2, it is chalcopyrite, taking pyrite as an example, its automatic mineralogical analysis test is as follows Figure 2 As shown, the horizontal projection length of its cross section is measured as Figure 3 As shown; then L2=L1m+L2m=1.570687cm, S1=53.50%, S2=32.20%.

[0067] (9) Calculate the content of each metal sulfide in sample J13, where the content of the i-th metal sulfide is Mi', Mi'=ρi*Di*X, ​​and Ci=Mi'*Si, C22= ; where ρi is the density of the i-th metal sulfide; Di is the volume fraction of the i-th metal sulfide, Di=Li / ; X is the conversion coefficient; Ci is the mass fraction of sulfur in the i-th metal sulfide to the total mass of the sample J13; then M1'=ρ1*D1*X, M1'=ρ2*D2*X, C1=M1'*S1, C2=M2'*S2, C22=C1+C2=25.622%; D1=L1m / (L1m+L2m)=0.843703, D2=L2m / (L1m+L2m)=0.156297; X=10.05184%, M1'=44.10%, M2'=6.30%.

[0068] (10) Calculate the content of each metal sulfide in the original sample, where the content of the i-th metal sulfide in the original sample is recorded as Mi, then M1=M1'*C11 / C22=44.10%*0.24402 / 25.6221=0.42%, M2=M2'*C11 / C22=6.30%*0.24402 / 25.6221=0.06%.

[0069] Comparative Example 1 This comparative example provides a method for determining the content of metal sulfide, which specifically comprises the following steps: (1) Weigh 1000 g of the ore sample in Example 1 as the sample to be tested, with a grinding fineness of -0.074 mm and a content of 85%.

[0070] (2) Preparation of samples for automatic mineralogical analysis: Weigh 5 g of the ground sample and mix it evenly with a 400 mesh full-pass thermosetting phenolic epoxy resin in a volume ratio of 1:3. Curing was carried out in a mounting machine at a temperature of 150 °C and a pressure of 200 Bar. The cured sample was ground, polished and carbon-sprayed to obtain sample J13. The sizes of the grinding materials were 150 μm, 23 μm and 13 μm, and the grinding was carried out for 8 min. The sizes of the polishing materials were 6 μm, 3 μm and 1 μm, and the polishing was carried out for 8 min. The carbon spraying method was ion sputtering, and the carbon spraying thickness was 5 nm.

[0071] (3) Automatic mineralogical analysis was performed, and the magnification of the automatic mineralogical analysis instrument was adjusted to 800 times. The test results showed that the content of pyrite in 50,000 samples was 0.33%, and the content of chalcopyrite was 0.15%.

[0072] By comparing the test results of gold content in Example 1 and Comparative Example 1, it can be seen that the content of pyrite directly tested by the conventional automatic mineralogical analysis method in Comparative Example 1 is obviously low, while the content of chalcopyrite is high. This is because the conventional automatic mineralogical analysis method for low-content metal sulfides adopts the area method to determine the content of metal sulfides. On the one hand, the number of particles measured is too small, and on the other hand, the area of ​​low-content metal sulfides is less than that of other gangue minerals, which is accidental and leads to large deviations in the data.

[0073] Example 2 This embodiment provides a method for determining the volume ratio of metal sulfides, which specifically comprises the following steps: Sample J13 in Example 1 was sampled 5 times, and the method in step (8) of Example 1 was used to perform automatic mineralogical analysis to test the sum of the horizontal projection lengths Li of the cross sections of each metal sulfide in the sample, and the volume ratio Di of each metal sulfide in the sample was calculated based on this. The results are shown in Table 1.

[0074] Table 1 The sum of horizontal projection lengths and volume ratios of the cross sections of each metal sulfide in the samples obtained from the five tests in Example 2 Comparative Example 2 This comparative example provides a method for determining the volume ratio of metal sulfides, which specifically comprises the following steps: The volume ratio of each metal sulfide was measured 5 times using the linear method for sample J13 in Example 1. The test results are shown in Table 2.

[0075] The test method is: first place an eyepiece micrometer (ruler length 1cm, divided into 100 equal parts, one small grid length 0.1mm) at the focal plane of the eyepiece tube, and clamp the prepared light sheet with a mechanical stage on the stage. After adjusting the focal length, you will see a 100-part ruler superimposed on various mineral particles on the light sheet in the field of view, and then use the mechanical stage to move the first field of view to be measured to a certain base angle of the light sheet. At this time, you can start counting the number of grids intercepted by various mineral particles on the eyepiece ruler, that is, the intercept distance Bi. Count one field of view after another on a straight line. After measuring a straight line, use the mechanical stage to move the light sheet 2mm, and continue to measure the intercept distance of various mineral particles on the second measuring line. Until all the light sheets are checked and measured, 20 fields of view are measured.

[0076] Finally, the intercept distance Bi and volume ratio D of each metal sulfide in the sample are obtained. ， See Table 2 for details.

[0077] Table 2 Intercept distance and volume ratio of each metal sulfide in the samples obtained from the 5 tests in Comparative Example 2 By comparing the test results of the volume ratio of metal sulfides in Example 2 and Comparative Example 2, it can be seen that the test results of Example 2 and Example 2 are not much different, but the test result data of 5 in Example 2 is more stable, indicating that the test method results of this scheme are reliable, and the interference factors of manual operation are reduced, the test results are more stable, and the operation is simpler.

[0078] In summary, the present application provides a method for determining the content of metal sulfides. By performing sulfide phase analysis on samples after grinding and after re-selection and acid treatment enrichment, and performing automatic mineralogical analysis on samples after re-selection and acid treatment enrichment, the amplified data is corrected back to the data of the original sample, so as to achieve accurate measurement of the content of low-content metal sulfides, and the content of different metal sulfides can be measured separately through automatic mineralogical analysis. In addition, when testing the volume ratio of the particles, the ratio of the horizontal maximum intercepts of the particle exposure surface is used as the ratio of the volume of the particles. Compared with the traditional method of adding a scale to a microscope, measuring the ratio of the intercept lengths of the parallel straight lines of the particle series that cut through each mineral, which is equal to the volume ratio of each mineral, the method is more convenient and more suitable for automatic mineralogical analysis instrument detection, and greatly reduces the influence of human subjective factors. The test method provided by the present invention measures data accurately, greatly reduces the interference of human subjective factors, saves manpower, and provides reliable data support for the efficient use of such stone resources.

[0079] It should be noted that the present application is not limited to the above-mentioned embodiments. The above-mentioned embodiments are only examples, and the embodiments having the same structure as the technical idea and exerting the same effect within the scope of the technical solution of the present application are all included in the technical scope of the present application. In addition, without departing from the scope of the main purpose of the present application, various modifications that can be thought of by those skilled in the art to the embodiments and other methods of combining some of the constituent elements in the embodiments are also included in the scope of the present application.

Claims

1. A method for determining the content of metal sulfide, characterized in that: The following steps are involved: S1. Take the sample to be tested, grind it, and obtain a ground sample; S2. uniformly sampling the ground sample, performing a first sulfur phase analysis, and measuring the mass fraction of sulfur in the metal sulfide to the total mass of the ground sample as C11; S3. Re-select the sample after grinding to obtain a gravity-selected concentrate J1 and a gravity-selected tailing W1; S4. The gravity separation tailings W1 are treated with acid, then washed, filtered, and dried to obtain a sample W2; S5. Mixing the gravity separation concentrate J1 and sample W2 to obtain sample J12; S6. uniformly sample the sample J12, perform a second sulfur phase analysis, and measure the mass fraction of sulfur in the metal sulfide to the total mass of the sample J12 to be C22; S7. Sampling the sample J12 and preparing the sample J13 for automatic mineralogical analysis; S8. Perform automatic mineralogical analysis on the sample J13, and measure the sum of the horizontal projection lengths of the cross sections of various metal sulfides and the sulfur content of various metal sulfides, wherein the sum of the horizontal projection lengths of the cross sections of the i-th metal sulfide is recorded as Li, and the sulfur content of the i-th metal sulfide is recorded as Si; Li= , Lim represents the horizontal projection length of the cross section of the mth mineral grain in the i-th metal sulfide, i=1, 2, ..., n, n is the total number of types of metal sulfides measured, m=1, 2, 3, ..., N, N is the total number of mineral grains of the i-th metal sulfide; S9. Calculate the content of each metal sulfide in the sample J13, wherein the content of the i-th metal sulfide is recorded as Mi', Mi'=ρi*Di*X, ​​and Ci=Mi'*Si, C22= ; where ρi is the density of the i-th metal sulfide; Di is the volume fraction of the i-th metal sulfide, Di=Li / ; X is the conversion coefficient; Ci is the mass fraction of the mass of sulfur in the i-th metal sulfide to the total mass of the sample J13; S10. Calculate the content of each metal sulfide in the original sample, wherein the content of the i-th metal sulfide in the original sample is recorded as Mi, then Mi=Mi'*C11 / C22.

2. The method for determining the content of metal sulfide according to claim 1, characterized in that: In step S1, the grinding fineness is -0.074 mm and the content is 75% to 95%.

3. The method for determining the content of metal sulfide according to claim 1, characterized in that: In step S2, the first sulfur phase analysis includes: using a differential method or an acetic acid-hydrogen peroxide leaching method to measure the mass fraction of the mass of sulfur in the metal sulfide in the ground sample to the total mass of the ground sample.

4. The method for determining the content of metal sulfide according to claim 1, characterized in that: In step S3, the gravity separation adopts a heavy liquid stirring separation method, and the gravity separation reagent is a mixture of aqueous solutions of thallium formate and thallium malonate.

5. The method for determining the content of metal sulfide according to claim 1, characterized in that: In step S4, the acid in the acid treatment includes hydrofluoric acid and sulfuric acid; the temperature of the acid treatment is 90-95° C. in a water bath, and the time of the acid treatment is 22-26 hours.

6. The method for determining the content of metal sulfide according to claim 1, characterized in that: In step S7, the automatic mineralogical analysis sample preparation process includes: S71. The sample J12 is mixed with a thermosetting inlay material in a volume ratio of 1:0.5 to 1:3, and cured in an inlay machine at a temperature of 100 to 150°C and a pressure of 200 to 300 Bar; the thermosetting inlay material is a thermosetting phenolic epoxy resin, and the particle size of the thermosetting inlay material is not greater than 38 μm; S72. Grind and polish the solidified sample and perform carbon spraying. In the grinding and polishing, the sizes of the abrasives include 150 μm, 23 μm and 13 μm, and the grinding time is 8 to 10 min. The sizes of the polishing materials include 6 μm, 3 μm and 1 μm, and the polishing time is 8 to 10 min. The carbon spraying method is ion sputtering, and the thickness of the carbon spraying is 5 to 10 nm.

7. The method for determining the content of metal sulfide according to claim 1, characterized in that: In step S6, the second sulfur phase analysis includes: using a differential method or an acetic acid-hydrogen peroxide leaching method to measure the mass fraction of the mass of sulfur in the metal sulfide in the sample J12 to the total mass of the sample J12.

8. The method for determining the content of metal sulfide according to claim 1, characterized in that: In step S8, the magnification of the automatic mineralogical analysis test is 300-1000 times, and the number of particles tested is 30,000-50,000.

9. The method for determining the content of metal sulfide according to claim 1, characterized in that: In step S8, the horizontal projection length of the cross section of the i-th metal sulfide refers to the horizontal maximum intercept of the mineral particle leakage surface of the i-th metal sulfide.

10. The method for determining the content of metal sulfide according to claim 1, characterized in that: In step S8, the sulfur content Si of the i-th metal sulfide is an average value of the sulfur content measurement results of at least 10 mineral particles of the i-th metal sulfide.

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