Method for rapidly determining content of nonmetallic minerals in granite pegmatite

Abstract

The invention relates to the technical field of ore determination methods, in particular to a method for rapidly determining the content of nonmetallic minerals in granite pegmatite, which comprises the following steps: solidifying granite pegmatite minerals, and polishing to obtain polished sections; spraying the light sheet, and pasting a conductive adhesive to prepare a light sheet to be measured; dotting measurement is conducted on the to-be-measured light sheet, the content of the metal oxide in the non-metallic mineral is calibrated, and the theoretical grade of the metal oxide is obtained; carrying out a comprehensive recovery test on the non-metallic minerals to obtain mineral separation products; the content of the metal oxide in the mineral separation product is measured, and the corresponding element content is obtained; and substituting the element content into a formula to calculate the content of the nonmetallic minerals. In order to solve the problem of long time limit of the existing process mineralogy means, the mineral content of the nonmetallic mineral product can be quickly calibrated, the mineral separation efficiency can be improved, the quality of the product can be judged, and a reference is provided for formulation and adjustment of a subsequent mineral separation and recovery process flow scheme.

Description

Technical Field

[0001] The present application relates to the technical field of ore determination methods, and in particular to a method for rapidly determining the content of non-metallic minerals in granite. Background Art

[0002] With the continuous development of my country's economy, mineral resources have been extensively developed and utilized, and resources are becoming increasingly depleted. The recycling of non-metallic minerals as secondary resources can not only effectively alleviate resource shortages and improve resource utilization efficiency, but also reduce the area of tailings storage, reduce the pollution of heavy metal ions in tailings to the environment, and minimize the occurrence of disasters such as landslides and collapses.

[0003] Mica is a widely used non-metallic aluminosilicate mineral, widely used in the materials, chemical, coatings, and cosmetics industries. Feldspar is an aluminosilicate mineral composed of alkali and alkaline earth metals such as potassium, sodium, calcium, and barium. It is primarily used in the glass industry (accounting for approximately 50% to 60% of total feldspar consumption) and the ceramics industry (accounting for approximately 30% of total feldspar consumption). Other applications include chemicals, abrasives, glass fiber, welding electrodes, enamels, and fillers.

[0004] Currently, mica and feldspar minerals are mostly recovered through flotation processes, producing mica concentrate and feldspar concentrate products. While there are currently no national standards for the quality of mica concentrate products, the quality is currently measured by K2O content. The quality of feldspar concentrate is often measured by K2O + Na2O content. For example, the industry standard for daily-use ceramic feldspar requires a qualified feldspar concentrate with a K2O + Na2O content of ≥10% for potassium feldspar, while a qualified feldspar concentrate requires a K2O + Na2O content of ≥8%. Both of these methods of characterizing product quality can be determined through chemical analysis of the elemental content of K2O and Na2O. Elemental analysis can only characterize the content of the main elements in the product and cannot directly reveal the mineral content of useful minerals such as mica and feldspar. XRD diffraction analysis, commonly used for mineral content determination, is a semi-quantitative mineral composition analysis method and cannot accurately determine the content of minerals such as mica and feldspar. XRD diffraction analysis combined with micro-analysis methods such as process mineralogy electron probe can characterize the mineral content in detail, but this method is time-consuming and labor-intensive and cannot be used to quickly characterize the content of minerals such as mica and feldspar during mineral processing and separation process tests, thereby providing support for the next step of process technology parameter selection.

[0005] Therefore, a new ore determination method is needed to solve the problem that the content of non-metallic minerals containing potassium, sodium and aluminum elements such as mica, albite and potassium feldspar in granite pegmatite cannot be quickly determined during the current laboratory mineral processing test. Summary of the Invention

[0006] The problem that this application aims to solve is to provide a method for rapid determination of non-metallic mineral content, which can achieve accurate and rapid determination of the mineral content of non-metallic mineral products in ores, and solve the technical problems that traditional flotation processes and element determination processes are time-consuming and labor-intensive and cannot accurately determine the mineral content.

[0007] In order to solve the above technical problems, this application adopts the following technical solutions:

[0008] On the one hand, the present application provides a method for rapidly determining the content of non-metallic minerals, comprising the following steps:

[0009] After solidifying the granite pegmatite mineral, it is polished to obtain a light sheet;

[0010] The optical sheet is subjected to spraying and pasting with conductive adhesive to obtain an optical sheet to be tested;

[0011] Performing point measurement on the optical sheet to be measured, calibrating the content of metal oxides in the non-metallic mineral, and taking an average value of the content to obtain the theoretical grade of the metal oxides in the non-metallic mineral;

[0012] Conducting a comprehensive recovery test on the non-metallic minerals to obtain mineral processing products;

[0013] Determining the content of the metal oxide in the mineral processing product to obtain the corresponding element content;

[0014] Substitute the element content into the formula for mica and feldspar products to calculate the content of the non-metallic mineral.

[0015] Preferably, the optical sheet is sputtered by using a Cressington 108carbon / A high-performance ion sputtering apparatus to coat the prepared optical sheet with a carbon conductive film to obtain the optical sheet to be tested;

[0016] Specifically, the optical sheet is placed on the electron microscope sample stage and observed through the electron microscope to select the area to be analyzed. The sample stage position is then adjusted and the target mineral is determined using the energy spectrum so that the analysis point is exactly at the bombardment point of the electron beam.

[0017] Specifically, according to the sample type and analysis requirements, the acceleration voltage, beam current and other parameters of the electron beam are set, and an appropriate analysis mode is selected, and the determined analysis points are measured, the content of the metal oxide in the non-metallic mineral is calibrated at least five times, and the average value of the content is taken to obtain the theoretical grade of the metal oxide of the non-metallic mineral;

[0018] Preferably, place the light sheet sample into an EPMA-1720 electron probe and observe it using an electron microscope to select the area to be analyzed. The sample stage is then adjusted, and target minerals such as potassium feldspar, sodium feldspar, and mica are identified using energy spectrum analysis, ensuring that the analysis point is precisely aligned with the impact point of the electron beam. The electron beam is set to an accelerating voltage of 15.0 kV, a beam current of 20.0 nA, a beam span of 5 μm, and an appropriate analysis mode. The dotted measurement is then performed and repeated six times.

[0019] Preferably, the non-metallic minerals include aluminosilicate minerals such as mica, potassium feldspar, and sodium feldspar.

[0020] Preferably, the metal oxides include: K2O, Na2O, Al2O3.

[0021] Specifically, the formula includes:

[0022]

[0023] Wherein Ai is the content of the non-metallic mineral in the product (%);

[0024] Bi—theoretical grade value of the metal oxide in the product (%);

[0025] Mi—content of the metal oxide in the product (%);

[0026] i represents the number of types of chemical elements. The specific content of each chemical element is equal to the product of the mineral content in the corresponding non-metallic mineral concentrate and the theoretical grade of the element. The corresponding non-metallic mineral content in different non-metallic mineral products is calculated based on this, and n≤3.

[0027] Specifically, the grinding includes: coarse grinding, fine grinding, fine grinding, and polishing;

[0028] Specifically, the curing step includes the following steps: curing the granite pegmatite mineral in a casting mold with epoxy resin.

[0029] Specifically, the concentrate, middlings and tailings beneficiation products obtained through the mineral beneficiation recovery test of mica, potassium feldspar, sodium feldspar and other minerals include the mica and feldspar mineral concentrate, middlings and tailings beneficiation products obtained by direct flotation or reverse flotation.

[0030] On the other hand, the present application provides the application of the above method in determining the content of granite pegmatite in ore, which is suitable for determining the content of minerals containing only three or less elements of K2O, Na2O, and Al2O3, that is, the content of these three elements in other non-metallic minerals is extremely low.

[0031] This application has the following beneficial effects:

[0032] (1) The method provided in this application for rapidly determining the content of non-metallic minerals in granite combines the theoretical grade analysis of mineral processing with the element determination of the product, and uses an electron probe to simultaneously measure different elements, which not only improves the efficiency of calibration and reduces the measurement cost, but also improves the accuracy of calibration.

[0033] (2) The method provided in this application for rapidly determining the content of non-metallic minerals in granite can efficiently determine the mineral content of non-metallic minerals such as mica, albite, and potassium feldspar in granite. Compared with traditional methods, it can quickly calibrate the mineral content of products such as mica, potassium feldspar, and albite, and determine the quality of the products, which is conducive to the formulation and adjustment of subsequent mineral processing and recovery process plans, saving time and labor costs, and achieving significant benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] To more clearly illustrate the technical solutions of the present disclosure, the following briefly introduces the drawings required for use in some embodiments of the present disclosure. Obviously, the drawings described below are only drawings of some embodiments of the present disclosure, and those skilled in the art can also derive other drawings based on these drawings. In addition, the drawings described below can be regarded as schematic diagrams and are not intended to limit the actual process of the methods involved in the embodiments of the present disclosure.

[0035] Figure 1 This is the light sheet prepared in the embodiment of this application (the left and right figures are both light sheets prepared in this application);

[0036] Figure 2 The scanning electron microscope and energy spectrum analysis of albite in the examples of this application (Figure A is a scanning electron microscope image of albite, with a magnification of 150 times, and Figure B is an energy spectrum analysis of albite);

[0037] Figure 3 The scanning electron microscope and energy spectrum analysis of potassium feldspar in the examples of this application (Figure A is a scanning electron microscope image of potassium feldspar, with a magnification of 150 times, and Figure B is an energy spectrum analysis of potassium feldspar);

[0038] Figure 4 The scanning electron microscope and energy spectrum analysis of mica in the examples of this application (Figure A is a scanning electron microscope image of mica, with a magnification of 150 times, and Figure B is an energy spectrum analysis of mica). DETAILED DESCRIPTION

[0039] The following is a clear and complete description of the technical solutions in some embodiments of the present disclosure. Obviously, the embodiments described are only some of the embodiments of the present disclosure, not all of them. Based on the embodiments provided by the present disclosure, all other embodiments obtained by ordinary technicians in this field are within the scope of protection of the present disclosure.

[0040] Example

[0041] The raw ore was mixed and fractionated to produce optical slices. The KO, NaO, and AlO contents of each of the mica, potassium feldspar, and albite in the raw ore were determined by electron microprobe dotting. Subsequently, the KO, NaO, and AlO contents of the remaining samples (such as the mica concentrate and feldspar concentrate) were determined by chemical analysis. The KO, NaO, and AlO contents of each of the mica, potassium feldspar, and albite determined by electron microprobe determination of the raw ore were combined with the KO, NaO, and AlO contents of the samples to be measured to calculate the mica, potassium feldspar, and albite contents. For example, if the KO, NaO, and AlO contents of each of the mica, potassium feldspar, and albite in the raw ore were determined by electron microprobe determination, and the KO, NaO, and AlO contents of samples 1 and 2 to be measured were subsequently determined by chemical analysis, the mica, potassium feldspar, and albite contents of samples 1 and 2 to be measured could be calculated. The calculated results are shown in Table 1. The specific measurement steps are as follows:

[0042] S1. Preparation of optical slices: Take 50g of raw ore sample (grinding fineness is 0.2mm or less), mix and disperse the sample, take 5g of the sample and solidify the sample with epoxy resin in a casting mold with a diameter of 30mm, and then perform coarse grinding, fine grinding, fine grinding and polishing in sequence to make optical slices.

[0043] S2. Sputtering the optical sheet: The optical sheet prepared in step 1 is subjected to carbon conductive film coating using a Cressington 108 carbon / A high-performance ion sputtering apparatus to obtain an optical sheet to be tested.

[0044] S3. Place the sample prepared in step 2 into the EPMA-1720 electron probe. Observe the sample using the electron microscope and select the area to be analyzed. Adjust the sample stage and use energy spectrum analysis to identify target minerals such as potassium feldspar, sodium feldspar, and mica, ensuring that the analysis point is precisely aligned with the electron beam's impact point. Set the electron beam acceleration voltage to 15.0 kV, the beam current to 20.0 nA, the measurement beam span to 5 μm, and select the appropriate analysis mode. Perform a dotted measurement and repeat six times.

[0045] S4. Analysis of the theoretical grade of mineral elements: After measuring the three major points in step 1, calibrate the K2O, Na2O, and Al2O3 contents in minerals such as mica, potassium feldspar, and albite multiple times, and take the average value, which is the theoretical grade of K2O, Na2O, and Al2O3 in minerals such as mica, potassium feldspar, and albite.

[0046] S5. Data analysis: Determination of mineral content of mica and feldspar products: After completing the element determination in step 4, the concentrate, middlings, tailings and other products produced during the mineral processing recovery test can be subjected to chemical analysis and determination of the K2O, Na2O, and Al2O3 element content. After obtaining the accurate element chemical content, the content of mica, albite, and potassium feldspar minerals in the product can be quickly calculated according to the following formula:

[0047]

[0048] Among them A i —Mineral content of specific minerals in the product (%);

[0049] B i —Theoretical grade of specific elements of specific minerals in the product (%);

[0050] Mi—measured grade of specific elements in the product (%);

[0051] i represents the three metal oxides K2O, Na2O, and Al2O3. The specific content of each element (obtained from laboratory tests) is equal to the product of the corresponding mineral content in the mica concentrate, albite concentrate, and potash feldspar concentrate and the element. The corresponding mica mineral, potash feldspar mineral, and albite mineral content in the three mica concentrate, albite concentrate, and potash feldspar concentrate products are calculated based on this.

[0052] Table 1 Test mineral content

[0053]

[0054] Comparative Example

[0055] An experiment was added to determine the content of non-metallic minerals in granite pegmatite using traditional methods. After the beneficiation intermediate products were mixed and divided, 50g of the sample was taken out and ground finely, and then a semi-quantitative XRD diffraction analysis was performed. The test results are shown in Table 2.

[0056] The same beneficiation intermediate product was mixed and dispersed, then cured with epoxy resin in a 30 mm diameter mold. The sample was then subjected to coarse grinding, fine grinding, fine grinding, polishing, and coating to produce a film for testing. The sample was then placed in an EPMA-1720 electron probe to identify the target area and mineral. The appropriate analysis mode was selected, and spot measurements were performed six times to determine the theoretical elemental grade of each target mineral. Combined with the results of elemental chemical analysis, the content of quartz, potassium feldspar, and sodium feldspar was accurately quantified. The test results of this method are shown in Table 2.

[0057] Experimental Example Comparison of the Effects of This Application and Traditional Methods

[0058] The methods of the embodiment and the comparative example were used to measure minerals with known compositions, and the accuracy, measurement time and other data were compared. The comparison results are shown in Table 2.

[0059] The XRD diffraction analysis test results in Table 2 have large deviations, and the measurement time is 12 hours. The mineral content test results by scanning electron microscopy are close to those of this test method, but the measurement time is 72 hours, which is time-consuming. This determination method has high accuracy and is less time-consuming.

[0060] Table 2 Grade differences of the same mineral by different determination methods

[0061]

Claims

1. A method for rapidly determining the content of non-metallic minerals in granite pegmatite, characterized in that: The steps include: After solidifying the granite pegmatite mineral, it is polished to obtain a light sheet; The optical sheet is subjected to spraying and pasting with conductive adhesive to obtain an optical sheet to be tested; Performing point measurement on the optical sheet to be measured to calibrate the content of the metal oxide in the non-metallic mineral, and taking an average value of the content to obtain the theoretical grade of the metal oxide in the non-metallic mineral; Conducting a comprehensive recovery test on the non-metallic minerals to obtain mineral processing products; Determining the content of the metal oxide in the mineral processing product to obtain the corresponding element content; Substitute the element content into the formula for mica and feldspar products to calculate the content of the non-metallic mineral.

2. The method according to claim 1, wherein: The non-metallic minerals include aluminosilicate minerals such as mica, potassium feldspar, sodium feldspar, etc. The metal oxides include K2O, Na2O, and Al2O3; The mineral processing products include concentrate, middlings and tailings.

3. The method according to claim 1, wherein: The number of times of calibrating the non-metallic minerals is at least five.

4. The method according to claim 1, wherein The formula of mica and feldspar products is: Wherein Ai is the content of the non-metallic mineral in the product (%); Bi—theoretical grade value of the metal oxide in the product (%); Mi—content of the metal oxide in the product (%); i represents the number of types of chemical elements. The specific content of each chemical element is equal to the product of the mineral content in the corresponding non-metallic mineral concentrate and the theoretical grade of the element. The corresponding non-metallic mineral content in different non-metallic mineral products is calculated based on this, and n≤3.

5. The method according to claim 1, wherein: The grinding includes coarse grinding, fine grinding, fine grinding and polishing.

6. The method according to claim 1, wherein: The curing comprises the following steps: curing the granite pegmatite mineral in a casting mold with epoxy resin.

7. The method according to claim 1, wherein: The dot measurement comprises the following steps: placing the optical sheet into an original ore electronic probe and performing dot measurement.

8. The method according to claim 1, wherein: The comprehensive recovery experiment method includes one of forward flotation and reverse flotation.

9. Use of the method according to any one of claims 1 to 7 in determining the contents of mica, potassium feldspar and sodium feldspar in granite pegmatite.

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