阅读说明：本技术 一种石墨矿石中全矿物定量测定方法及制样方法 (Quantitative determination method for all minerals in graphite ore and sample preparation method ) 是由 李波 张莉莉 蒋英 洪秋阳 李美荣 梁冬云 于 2020-12-15 设计创作，主要内容包括：本发明属于矿物分析检测技术领域,具体公开了一种石墨矿石中全矿物的定量测定方法,同时还公开了一种石墨矿石全矿物定量测定中的制样方法。本发明针对现有石墨矿难以对其进行准确定量测定的问题,在自动工艺矿物学定量分析法基础上,使用改进的样品处理方法,特别是对石墨矿石样品进行合适的镶嵌和磨抛处理,实现了对石墨矿石全矿物的准确定量。本发明为地质、选矿、冶金、材料等研究领域提供了一种新的技术手段,并对含石墨的矿产资源的找矿、综合利用以及优化工艺流程提供了矿物学基础。(The invention belongs to the technical field of mineral analysis and detection, and particularly discloses a quantitative determination method for all minerals in graphite ore, and a sample preparation method for quantitative determination of all minerals in graphite ore. Aiming at the problem that the conventional graphite ore is difficult to accurately and quantitatively determine, the method uses an improved sample processing method on the basis of an automatic process mineralogy quantitative analysis method, and particularly carries out proper inlaying, grinding and polishing treatment on the graphite ore sample, so that the accurate quantification of the whole mineral of the graphite ore is realized. The invention provides a new technical means for the research fields of geology, mineral separation, metallurgy, materials and the like, and provides a mineralogy basis for mineral exploration, comprehensive utilization and process flow optimization of mineral resources containing graphite.)

1. The sample preparation method for quantitative determination of all minerals in graphite ore is characterized by comprising a graphite ore sample preparation step, wherein the graphite ore sample preparation step comprises inlaying treatment on a graphite ore sample, and the inlaying treatment is to treat the graphite ore sample by using palm wax and epoxy resin.

2. The sample preparation method according to claim 1, wherein the step of preparing the graphite ore sample further comprises grinding and polishing the graphite ore sample after the inlaying treatment, and the grinding and polishing treatment adopts the following procedures in sequence: coarse grinding, primary fine grinding, secondary fine grinding, coarse polishing and fine polishing;

preferably, the rough grinding is carried out in an aqueous medium by using a SiC grinding disc, and the SiC granularity is 500 #; and/or the presence of a gas in the gas,

the primary fine grinding is carried out in an aqueous medium by using a SiC grinding disc, and the SiC granularity is 1200 #; and/or the presence of a gas in the gas,

the secondary fine grinding is carried out in an aqueous medium by using a SiC grinding disc, and the granularity of SiC is 2000 #; and/or the presence of a gas in the gas,

the rough polishing is carried out in a diamond suspension medium by adopting a synthetic short-fiber grinding disc, and the specification of the diamond suspension is 3 mu m; and/or the presence of a gas in the gas,

the fine polishing is carried out in a diamond suspension medium by adopting a synthetic short-fiber grinding disc, and the specification of the diamond suspension is 1 mu m.

3. A sample preparation method as claimed in claim 1 or 2, wherein the inlaying treatment is carried out by inlaying the graphite ore sample with carnauba wax and then carrying out cold inlaying treatment with epoxy resin.

4. A sample preparation method according to any one of claims 1 to 3, wherein when the particle size of the graphite ore sample is larger than 0.02mm, the adopted mosaic treatment method comprises the following steps: putting a sample to be processed into a mold, heating the mold, pouring molten palm wax into the mold, stirring, performing vacuum exhaust, splitting the sample into two halves along the longitudinal plane by using a cutting machine after the sample is completely solidified, drying, putting the two halves of the sample into the mold with the longitudinal planes facing downwards, and injecting epoxy resin for cold inlaying to obtain a graphite ore resin polished section; and/or the presence of a gas in the gas,

when the particle size of the graphite ore sample is less than 0.02mm, the adopted inlaying treatment method comprises the following steps: putting a sample to be processed into a mould, adding absolute ethyl alcohol into the mould, dispersing by ultrasonic oscillation, pouring molten palm wax into the mould after complete dispersion and volatilization of the absolute ethyl alcohol are finished, uniformly stirring, then carrying out ultrasonic oscillation treatment, splitting the sample in half along the longitudinal plane by a cutting machine after the sample is completely solidified, drying, putting the two half samples into the mould with the longitudinal planes facing downwards, and injecting epoxy resin for cold inlaying to obtain the graphite ore resin polished section.

5. A sample preparation method as claimed in claim 2, wherein the rough grinding is carried out at a pressure of 12-18 kpa and a rotation speed of 75-100 r/min; and/or the presence of a gas in the gas,

the pressure of the primary fine grinding is 8-12 kpa, and the rotating speed is 75-100 r/min; and/or the presence of a gas in the gas,

the pressure of the secondary fine grinding is 12-18 kpa, and the rotating speed is 75-100 r/min; and/or the presence of a gas in the gas,

the pressure of the rough polishing is 15-25 kpa, and the rotating speed is 75-100 r/min; and/or the presence of a gas in the gas,

the pressure of the fine polishing is 15-25 kpa, and the rotating speed is 75-100 r/min.

6. A sample preparation method as claimed in claim 5, wherein the rough grinding is carried out at a pressure of 15kpa, a rotation speed of 90r/min and a rough grinding time of 5 min; and/or the presence of a gas in the gas,

the pressure of the primary fine grinding is 10kpa, the rotating speed is 90r/min, and the primary fine grinding time is 3 min; and/or the presence of a gas in the gas,

the pressure of the secondary fine grinding is 15kpa, the rotating speed is 90r/min, and the time of the secondary fine grinding is 3 min; and/or the presence of a gas in the gas,

the pressure of the rough polishing is 20kpa, the rotating speed is 90r/min, and the rough polishing time is 5 min; and/or the presence of a gas in the gas,

the pressure of the fine polishing is 20kpa, the rotating speed is 90r/min, and the fine polishing time is 3 min.

7. A method for quantitatively determining total minerals in graphite ore, characterized by comprising the sample preparation method steps according to any one of claims 1 to 6.

8. The quantitative determination method according to claim 7, further comprising a step of detecting the prepared sample;

the step of detecting the prepared sample is to adopt an MLA system to carry out analysis detection and data processing to obtain the quantitative composition of each mineral in the graphite ore.

9. The quantitative determination method according to claim 7 or 8, wherein the step of detecting the prepared sample comprises:

performing MLA system measurement after carbon spraying on graphite ore resin polished sections obtained by sample preparation; and the number of the first and second groups,

after MLA measurement is completed, the newly-built mineral list is sorted and named, classification batch processing is carried out, classified database images are processed, and finally an ore process mineralogy database is created to obtain content data of all minerals contained in the graphite ore.

10. The quantitative determination method according to claim 9, wherein the MLA system model is MLA 650; the SEM accelerating voltage is 20kV, and the beam spot is 7.0 nm;

in the BSE mode, respectively selecting carnauba wax and calcite as gray standard samples to adjust the contrast and brightness of the SEM, setting the gray value of the carnauba wax to be 0 and the gray value of the calcite to be 255;

selecting a resin polished section with the grain size of-0.074 mm +0.04mm and adopting a standard measurement mode; and/or, the resin polished section with the grain size of +0.074mm and-0.04 mm adopts an XBSE measurement mode.

Technical Field

The invention relates to the technical field of mineral analysis and detection, in particular to detection of graphite ore, particularly a quantitative determination method of all minerals in the graphite ore, and also relates to a sample preparation method in the quantitative determination of all minerals in the graphite ore.

Background

Graphite is a natural element mineral composed of carbon elements, and is a special non-metallic material with excellent performance. With the emergence of new high-tech materials of lithium ion batteries and graphene in recent years, graphite resources are more and more concerned by society and become strategic emerging mineral products acknowledged at home and abroad. The comprehensive utilization of graphite resources is not necessary to carry out deep research on process mineralogy and the like of the type of resources, including research on relative content, distribution relation, dissociation characteristics and occurrence state of carbon elements of valuable minerals such as graphite and the like. The quantitative analysis and determination of graphite mineral is the most central content of the research of the mineralogy of graphite technology. The existing quantitative analysis and determination methods of graphite mainly comprise a chemical analysis method, a polarizing microscope slide and slice determination method, an X-ray powder crystal diffraction quantitative analysis method, an automatic process mineralogy quantitative analysis method, a Raman spectrum analysis method and the like.

Chemical analysis methods generally employ fixed carbon or all carbon measurements. The measurement of the fixed carbon in the graphite ore is determined by adopting a loss-on-ignition method, and when a graphite sample contains mineral components which are easy to decompose, volatilize or oxidize, such as sulfide, carbonate and the like, the measurement method has larger error. The total carbon measurement method is usually a carbon-sulfur instrument method. Whether the fixed carbon measurement method or the full carbon measurement method is adopted, only the content of carbon or the content of fixed carbon in a graphite sample can be measured, but not the content of graphite, and other components in graphite resources cannot be quantitatively analyzed.

Quantitative analysis by polarization microscopy consists in grinding the ore into flakes or slices and measuring the mineral content in reflected or transmitted light. The mineral identification depends on human vision, so that the subjectivity is strong and the error is large. The OIS system (Optical Image Analysis) which has been developed rapidly in recent years can automatically measure minerals in ores according to differences of visible light reflection signals of the minerals in different wave bands. However, this method is only suitable for the analysis of graphite ore, which is only suitable for the analysis of ore samples with simple composition and large difference of reflected light properties between minerals.

The phase quantitative analysis of the X-ray powder crystal diffractometer adopts an internal standard method, an external standard method, a K value method, a Rietveld full-spectrum fitting method and the like, wherein the Rietveld full-spectrum fitting method is based on a known crystal structure model, structure parameters and a peak shape function, and a computer is adopted to adjust the parameters to enable the parameters to be approximately fitted with an experimental spectrum, so that the mineral composition and content in a sample, crystal structure data and the like can be obtained. The Rietveld full-spectrum fitting method reduces the influence of factors such as diffraction overlapping peaks, preferred crystal orientation and the like to a certain extent, but XRD cannot detect low-content minerals (the detection limit is different due to different substances and is generally about 0.1-10%). In addition, most of graphite has a flaky crystal form and flexibility, the preferred orientation of the crystal is very obvious, the sample preparation is difficult, and the powder crystallization is difficult, so that the quantitative analysis result of XRD is influenced.

An automatic process mineralogy quantitative analysis method (such as MLA, AMICS, TIMA and the like) based on a scanning electron microscope is to analyze a data image of a sample through the scanning electron microscope, distinguish different areas according to the difference of back scattering signals of mineral particles, analyze minerals according to a spectrum peak database of an energy spectrum and realize the automatic measurement of mineralogy parameters of an ore process. The method has wide measurement range and large statistical quantity, so the method has higher measurement precision and is a mineral quantitative analysis method widely applied at present. However, for the sample containing graphite, since graphite is composed of carbon atoms, the atomic number is low, the SEM back scattering signal is weak, and is equivalent to that of the commonly used epoxy resin embedding agent, the quantitative analysis of graphite cannot be realized by the conventional automatic process mineralogy quantitative analysis method.

Therefore, there is a need to provide a quantitative measurement method for graphite ore, so as to analyze the graphite ore more accurately and provide scientific technical support for the process mineralogy research of graphite.

Disclosure of Invention

The invention mainly solves the technical problem of providing a quantitative determination method for all minerals in graphite ore.

The invention solves another technical problem by providing a graphite ore sample preparation method in the quantitative determination of the whole minerals of the graphite ore.

In order to solve the technical problems, the invention adopts the following technical scheme.

In a first aspect, the invention provides a sample preparation method for quantitatively determining total minerals in graphite ores, which comprises a graphite ore sample preparation step, wherein the graphite ore sample preparation step comprises a step of carrying out inlaying treatment on a graphite ore sample, and the inlaying treatment is to treat the graphite ore sample by using palm wax and epoxy resin.

As a preferred embodiment of the present invention, the step of preparing the graphite ore sample further includes performing grinding and polishing treatment on the graphite ore sample after the inlaying treatment, and the grinding and polishing treatment sequentially adopts the following procedures: coarse grinding, primary fine grinding, secondary fine grinding, coarse polishing and fine polishing;

preferably, the rough grinding is carried out in an aqueous medium by using a SiC grinding disc, and the SiC granularity is 500 #; and/or the presence of a gas in the gas,

the primary fine grinding is carried out in an aqueous medium by using a SiC grinding disc, and the SiC granularity is 1200 #; and/or the presence of a gas in the gas,

the secondary fine grinding is carried out in an aqueous medium by using a SiC grinding disc, and the granularity of SiC is 2000 #; and/or the presence of a gas in the gas,

the rough polishing is carried out in a diamond suspension medium by adopting a synthetic short-fiber grinding disc, and the specification of the diamond suspension is 3 mu m; and/or the presence of a gas in the gas,

the fine polishing is carried out in a diamond suspension medium by adopting a synthetic short-fiber grinding disc, and the specification of the diamond suspension is 1 mu m.

In a preferred embodiment of the present invention, the inlaying treatment is performed by inlaying the graphite ore sample with palm wax and then performing a cold inlaying treatment with epoxy resin.

As a preferred embodiment of the present invention, the graphite ore sample is a graphite-containing ore, including raw graphite ore, graphite concentrate or other graphite-containing product, and the graphite ore is subjected to a crushing treatment before the inlaying treatment.

In a preferred embodiment of the present invention, when the particle size of the graphite ore sample is larger than 0.02mm, the method for performing the inlaying treatment comprises: putting a sample to be processed into a mould, heating the mould, pouring molten palm wax into the mould, stirring, performing vacuum exhaust, splitting the sample into two halves along the longitudinal plane by using a cutting machine after the sample is completely solidified, drying, putting the two halves of the sample into the mould with the longitudinal planes facing downwards, and injecting epoxy resin for cold inlaying to obtain the graphite ore resin polished section.

In a preferred embodiment of the present invention, when the particle size of the graphite ore sample is less than 0.02mm, the method for performing the inlaying treatment comprises: putting a sample to be processed into a mould, adding absolute ethyl alcohol into the mould, dispersing by ultrasonic oscillation, pouring molten palm wax into the mould after complete dispersion and volatilization of the absolute ethyl alcohol are finished, uniformly stirring, then carrying out ultrasonic oscillation treatment, splitting the sample in half along the longitudinal plane by a cutting machine after the sample is completely solidified, drying, putting the two half samples into the mould with the longitudinal planes facing downwards, and injecting epoxy resin for cold inlaying to obtain the graphite ore resin polished section.

In a preferred embodiment of the invention, the pressure used for the rough grinding is 12-18 kpa, and the rotating speed is 75-100 r/min.

The pressure of the primary fine grinding is 8-12 kpa, and the rotating speed is 75-100 r/min.

The pressure of the secondary fine grinding is 12-18 kpa, and the rotating speed is 75-100 r/min.

The pressure of the rough polishing is 15-25 kpa, and the rotating speed is 75-100 r/min.

The pressure of the fine polishing is 15-25 kpa, and the rotating speed is 75-100 r/min.

As a more preferable embodiment of the present invention, the rough grinding is performed under a pressure of 15kpa, at a rotation speed of 90r/min, and for a rough grinding time of 5 min.

The pressure of the primary fine grinding is 10kpa, the rotating speed is 90r/min, and the primary fine grinding time is 3 min.

The pressure of the secondary fine grinding is 15kpa, the rotating speed is 90r/min, and the time of the secondary fine grinding is 3 min.

The pressure of the rough polishing is 20kpa, the rotating speed is 90r/min, and the rough polishing time is 5 min.

The pressure of the fine polishing is 20kpa, the rotating speed is 90r/min, and the fine polishing time is 3 min.

In a second aspect, the invention provides a method for quantitatively determining total minerals in graphite ores, which comprises a sample preparation step, wherein the sample preparation step adopts the sample preparation method steps.

As a preferred embodiment of the present invention, the quantitative determination method further comprises the step of detecting the prepared sample;

the step of detecting the prepared sample is to adopt an MLA system to carry out analysis detection and data processing to obtain the quantitative composition of each mineral in the graphite ore.

As a preferred embodiment of the present invention, the step of detecting the prepared sample comprises:

performing MLA system measurement after carbon spraying on graphite ore resin polished sections obtained by sample preparation; and an analysis step after completion of the MLA measurement.

The data analysis method adopted in the analysis step is an analysis method commonly used in an MLA system (mineral parameter automatic quantitative analysis system), and comprises the following steps: and (3) arranging and naming the newly-built mineral list, carrying out classification batch processing, processing the classified database images, and finally creating an ore process mineralogy database to obtain the content data of each mineral contained in the graphite ore.

Preferably, the MLA system model is MLA 650; the SEM accelerating voltage is 20kV, and the beam spot is 7.0 nm;

in the BSE mode, respectively selecting carnauba wax and calcite as gray standard samples to adjust the contrast and brightness of the SEM, setting the gray value of the carnauba wax to be 0 and the gray value of the calcite to be 255;

selecting resin polished sections with the grain size of-0.074 mm +0.04mm and adopting a standard measurement mode, and selecting resin polished sections with other grain sizes and adopting an XBSE measurement mode;

the measurement area is a representative area.

Sample preparation is a key step in the quantitative measurement of all minerals in graphite ore. The current conventional automated process mineralogy quantitative analysis method (such as MLA) adopts epoxy resin as embedding agent to inlay and prepare samples. However, for the graphite-containing sample, since graphite is composed of carbon atoms, the atomic number is low, and the SEM back scattering signal is very weak, which is equivalent to that of the epoxy resin embedding agent. Therefore, when the graphite ore is detected, the target mineral is usually subtracted as a background because the back scattering signal of the target mineral is close to that of the scanning electron microscope of the conventional epoxy resin embedding agent, and the detection of the graphite is not facilitated. Therefore, the conventional automatic process mineralogy quantitative analysis method cannot realize the quantitative analysis of the graphite at all. According to the invention, the palm wax is firstly used for inlaying, and then the epoxy resin is used for cold inlaying treatment, so that the prepared test sample can effectively separate the graphite from the embedding agent background. During detection, in the BSE mode, the carnauba wax and the calcite are respectively selected as gray standard samples to adjust the contrast and the brightness of the SEM, the carnauba wax gray value is set to be 0, the calcite gray value is set to be 255, and accurate detection can be achieved.

The polish-grind process step after the damascene process is also critical. Since graphite ore is different from coal mine samples, the graphite samples have more mineral species and great difference in hardness and brittleness among minerals, the conventional grinding and polishing method can cause the high-hardness and brittle minerals to fall off from a polished sheet, and therefore the detection result is inaccurate. By adopting the grinding and polishing scheme of the graphite sample polished section, provided by the invention, coarse grinding, primary fine grinding, secondary fine grinding, coarse polishing and fine polishing are sequentially carried out, and the grinding and polishing scheme is carried out through the sequence of a plurality of procedures, so that high-hardness and brittle minerals can be ensured not to fall off from the polished section, the minerals can be completely reserved, and the guarantee is provided for the accurate determination of the next step.

Aiming at the problem that the existing graphite ore is difficult to accurately and quantitatively determine, the invention uses an improved sample processing method on the basis of an automatic process mineralogy quantitative analysis method, particularly carries out proper inlaying and grinding and polishing treatment on the graphite ore sample, and realizes accurate quantification of the whole mineral of the graphite ore through proper detection conditions, particularly the setting of measurement parameters. The invention provides a new technical means for the research fields of geology, mineral separation, metallurgy, materials and the like, and provides a mineralogy basis for mineral exploration, comprehensive utilization and process flow optimization of mineral resources containing graphite.

Drawings

FIG. 1 is a graph of the post-polishing scattering of a graphite ore sample according to example 1 of the present invention;

fig. 2 is a graph of the scattering after polishing of a graphite concentrate sample according to example 2 of the present invention.

Detailed Description

The technical solution of the present invention will be described in detail by the following specific examples.

Example 1

The embodiment is a method for quantitatively determining all minerals in certain graphite ore, and the specific process is as follows:

the method comprises the following steps: a representative graphite ore is crushed to-0.2 mm and 100g of the sample is then reduced to obtain 4 fractions of +0.074mm, +0.04mm, +0.02mm and-0.02 mm by sieving and elutriation.

Step two: for 3 size fraction products larger than 0.02mm, 2-4 g of samples are respectively put into 3 molds with the diameter of 25mm, and the molds are put on a stone plate and then put into an oven with the temperature of 130 ℃ for standby. About 10g of palm wax was weighed into a 50mL beaker and heated in an electric furnace to completely melt the wax. Taking the stone plate and the mold out of the oven, pouring molten carnauba wax into the mold, quickly stirring, placing into a vacuum drying box, exhausting for 5 minutes, taking out, cutting the sample into halves along the longitudinal side by a cutting machine after the sample is completely solidified, drying, placing the two halves of the sample into the mold with the longitudinal sides facing downwards, and injecting prepared epoxy resin for cold embedding.

Step three: aiming at the problem that a mud sample with the granularity of less than 0.02mm is difficult to disperse due to agglomeration and reunion, the ultrasonic wave is adopted for preparing the sample. Grinding the dried mud sample, putting 0.3-0.5 g of sample into a mold, adding 3-5 mL of absolute ethyl alcohol by using a dropper, putting into an ultrasonic cleaning instrument, oscillating for pre-dispersion, pouring molten palm wax into the mold and uniformly stirring after the agglomerated particles are completely dispersed and the absolute ethyl alcohol is completely volatilized, putting into an ultrasonic cleaning instrument with a 100 ℃ water bath, oscillating for 5 minutes, taking out, splitting the sample into halves along the longitudinal plane by using a cutting machine after the sample is completely solidified, putting the two halves of the sample into the mold with the longitudinal plane facing downwards after drying, and injecting prepared epoxy resin for cold embedding.

Step four: and cutting off surface resin on the testing surface of the polished section sample cured in the second step and the third step to expose ore particles, and then grinding and polishing. The grinding and polishing adopts Seter equipment, consumables such as grinding disc abrasive materials are purchased from Seter company, and the grinding and polishing steps are sequentially as follows: rough grinding, primary fine grinding, secondary fine grinding, rough polishing and fine polishing, wherein the specific operations are shown in Table 1. Wherein DP is the diamond suspension medium, and 3 μm and 1 μm are the specifications of the diamond suspension. The MD-Nap is a synthetic short fiber grinding disc.

TABLE 1 operating conditions of the sample polishing step

Step five: the polished resin sheets were subjected to MLA system (model: MLA650) measurement after carbon spraying.

The SEM accelerating voltage is 20kV, the beam spot is 7.0nm, the contrast and the brightness of the SEM are adjusted by respectively selecting carnauba wax and calcite as gray scale samples in a BSE mode, the gray value of the carnauba wax is set to be 0, the gray value of the calcite is set to be 255, and a scattering diagram of a polished graphite ore sample is shown in figure 1.

Selecting the 0.074mm +0.04mm size fraction of the polished section, adopting a standard measurement mode, adopting an XBSE measurement mode for the resin polished sections of other size fractions, and selecting a representative rectangular area as a measurement area.

Step six: after MLA measurement is completed, the newly-built mineral list is sorted and named, classification batch processing is carried out, classified database images are processed, distinction between epoxy resin and graphite is noticed, and finally an ore process mineralogy database is created to obtain a data table of accurate content of all minerals containing graphite, which is specifically shown in table 2.

TABLE 2 composition and content of each mineral in graphite ore

Mineral substance	Relative content (wt%)	Mineral substance	Relative content (wt%)
				Graphite (II)	26.70	Limonite	0.15
Vanadium mica	21.45	Rutile type	0.21
				Quartz	50.52	Zircon stone	0.02
Feldspar	0.09	Monazite	0.03
				Tourmaline	0.04	Molybdenite	0.02
Clay mineral	0.20	Others	0.61

Example 2

The embodiment is a quantitative determination method for all minerals in graphite concentrate, and the specific process is as follows:

the method comprises the following steps: and (3) taking 1-2 g of a representative sample of the graphite concentrate sample, ultrasonically cleaning the sample for 5 minutes by using absolute ethyl alcohol, and drying the sample for later use.

Step two: and putting the dried sample into a mold with the diameter of 25mm, putting the mold on a stone plate, and putting the stone plate into an oven with the temperature of 130 ℃ for later use. About 3g of palm wax was weighed and placed in a beaker with a capacity of 50mL, and the beaker was heated in an electric furnace to be completely melted. Taking the stone plate and the mold out of the oven, pouring molten carnauba wax into the mold, quickly stirring, placing into a vacuum drying box, exhausting for 5 minutes, taking out, cutting the sample into halves along the longitudinal side by a cutting machine after the sample is completely solidified, drying, placing the two halves of the sample into the mold with the longitudinal sides facing downwards, and injecting prepared epoxy resin for cold embedding.

Step three: and cutting off surface resin on the test surface of the cured polished section sample to expose ore particles, and then grinding and polishing. The grinding and polishing steps were the same as the fourth step in example 1, and the grinding and polishing were carried out using the same equipment and consumables as those used in Setel, the details of which are shown in Table 1.

Step four: the prepared resin sheets were subjected to MLA system (model: MLA650) measurement after carbon spraying.

The SEM acceleration voltage is 20kV, the beam spot is 7.0nm, the contrast and the brightness of the SEM are adjusted by respectively selecting carnauba wax and calcite as gray scale samples in a BSE mode, the gray value of the carnauba wax is set to be 0, the gray value of the calcite is set to be 255, and a standard measurement mode is adopted. The scattering diagram of the polished graphite concentrate sample is shown in fig. 2.

Step five: after MLA measurement is completed, the newly-built mineral list is sorted and named, classification batch processing is carried out, classified database images are processed, distinction between epoxy resin and graphite is noticed, and finally an ore process mineralogy database is created to obtain a data table containing accurate content of all minerals of graphite concentrate, and the data table is specifically shown in table 3.

TABLE 3 certain graphite concentrate mineral composition and content

Mineral substance	Relative content (wt%)	Mineral composition	Relative content (wt%)
				Graphite (II)	97.49	Limonite	0.19
Vanadium mica	1.05	Clay mineral	0.12
				Quartz	1.04	Others	0.11

The graphite concentrate sample was subjected to quantitative analysis by X-ray diffraction Rietveld full-spectrum fitting, and the results are shown in table 4.

TABLE 4 quantitative analysis result of graphite concentrate XRD Rietveld full spectrum fitting

Mineral substance	Relative content (wt%)
		Graphite (II)	86.6
Mica	0.1
		Quartz	13.3

The graphite concentrate sample was also subjected to fixed carbon chemical analysis and found to be 96.45%. It can be seen that the results of the full-mineral determination of the graphite-containing ores by the method are superior to that of the XRD Rietveld full-spectrum fitting quantitative analysis method and are closer to the results of chemical analysis.

It can be seen from the above examples 1 and 2 that the sample preparation steps are improved, the palm wax is firstly used for inlaying, and then the epoxy resin is used for cold inlaying treatment, so that the graphite and the embedding agent background can be effectively separated from each other by the prepared test sample. And then, a grinding and polishing scheme of coarse grinding, primary fine grinding, secondary fine grinding, coarse polishing and fine polishing is adopted, parameters and reagents in the grinding and polishing scheme are reasonably set, and the grinding and polishing scheme is performed through the sequence of a plurality of procedures, so that high-hardness and brittle minerals are prevented from falling off from polished slices, the minerals are completely reserved, and accurate determination is guaranteed. During detection, in the BSE mode, the carnauba wax and the calcite are respectively selected as gray standard samples to adjust the contrast and the brightness of the SEM, the carnauba wax gray value is set to be 0, the calcite gray value is set to be 255, and accurate detection can be achieved. Finally, accurate quantitative detection of the graphite ore total minerals is realized.

Although the invention has been described in detail hereinabove by way of general description, specific embodiments and experiments, it will be apparent to those skilled in the art that many modifications and improvements can be made thereto based on the invention. Accordingly, such modifications and improvements are intended to be within the scope of the invention as claimed.