A method for determining the distribution characteristics of metal minerals in coal based on spectral induced polarization

Abstract

The present invention discloses a method for determining the distribution characteristics of metal minerals in coal based on spectrum induced polarization, comprising the following steps: S1, selecting a study area and collecting samples; S2, pre-processing the collected samples; S3, first qualitatively determining the minerals in the samples, and then quantitatively determining the minerals in the samples; S4, classifying the samples according to the metal mineral content; S5, processing the samples into a multi-electrode SIP measuring device; S6, sequentially using two adjacent electrodes in the multi-electrode SIP measuring device as power supply electrodes, and the electrode behind them as a measuring electrode, to measure corresponding data; S7, performing complex conductivity calculation on the collected SIP data; S8, inverting and analyzing the SIP data to obtain the electrical response and distribution characteristics of the metal minerals in the coal. The present invention adopts the above-mentioned method for determining the distribution characteristics of metal minerals in coal based on spectrum induced polarization, which can effectively establish the response relationship between the carrier minerals of strategic metals in coal series and geophysical parameters.

Description

Technical Field

[0001] The invention relates to the technical field of mineral exploration, and in particular to a method for determining the distribution characteristics of metal minerals in coal based on spectrum induced polarization method. Background Art

[0002] Strategic metals are the basic raw materials for the development of high-tech and emerging industries. With the depletion of traditional endogenous mineral resources and the increasing difficulty of mining, the search and development of strategic metal mineral resources in coal-based systems has become a new field and important direction for mineral resource exploration. Strategic metal minerals in coal-based systems are not only distributed in the coal seams themselves, but also in interlayers and roof and floor plates. Objectively, there are problems such as difficulty in identification and separation. Traditional metal mineral exploration technology cannot be applied to low-abundance strategic metal minerals in coal-based systems, and it is necessary to develop geophysical and geochemical exploration technology methods that integrate exploration.

[0003] At present, the joint and efficient exploration method system for geochemistry and geophysics of strategic metals in coal has not been established at home and abroad, and is still in the exploratory stage. Physical property parameters are the macroscopic reflection of mineral rocks, and are the comprehensive effects of various diagenetic elements and rock structure and structure. Based on the physical property characteristics of the main geophysical parameters in coal bodies rich in different strategic metals, such as resistivity and polarizability, the response relationship between the carrier minerals of coal-based strategic metals and geophysical parameters can provide a theoretical basis and technical support for the development and implementation of the geochemical and geophysical comprehensive exploration technology method system for coal-based strategic metal deposits. Due to the large-scale coal-based strategic metal deposits, their carrier minerals show many different characteristics in structure, chemical properties, mechanical properties and electrical properties. When the mineral particles and the electrolytes around them are subjected to electric fields of different frequencies, the cations and anions around the mineral particles will separate, thereby generating different types of polarization mechanisms. Therefore, it is not easy to distinguish and identify the distribution characteristics of metal minerals in coal with the existing technology, and it is difficult to establish the response relationship between physical property parameters and carrier minerals of strategic metals in coal. Summary of the invention

[0004] The purpose of the present invention is to provide a method for determining the distribution characteristics of metal minerals in coal based on spectral induced polarization, which can effectively establish the response relationship between the carrier minerals of strategic metals in coal and geophysical parameters.

[0005] To achieve the above object, the present invention provides a method for determining the distribution characteristics of metal minerals in coal based on spectral induced polarization method, comprising the following steps:

[0006] S1. Select the study area and collect samples;

[0007] S2, pre-processing the collected samples by sorting, crushing and grinding;

[0008] S3, using X-ray powder diffraction method to qualitatively analyze the minerals in the sample, and then using Siroquant mineral quantitative analysis system to quantitatively analyze the minerals in the sample;

[0009] S4. Classify the samples according to the metal mineral content test results of each sample;

[0010] S5, processing the sample into a multi-electrode SIP measurement device;

[0011] S6. Sequentially use two adjacent electrodes in the multi-electrode SIP measurement device as power supply electrodes, and the electrode behind them as a measurement electrode to measure the impedance amplitude Ω, the phase between the injection signal and the measurement signal and their respective errors;

[0012] S7, calculating the complex conductivity of the collected SIP data;

[0013] S8. By inversion analysis of SIP data, the electrical response and distribution characteristics of metal minerals in coal are obtained.

[0014] Preferably, in step S1, 3-5 typical coal seam profiles are selected, and when sampling, a number of block coal layers, interlayered gangue, roof and floor samples are taken in sequence from top to bottom of the coal seam profile at the same intervals.

[0015] Preferably, in step S5, the lump coal sample is processed into a cylindrical standard test sample with a radius of r and a height of h, and then an electrode sheet is attached to the test sample.

[0016] Preferably, electrode sheets are pasted on the test sample at the same interval, the longitudinal interval of the electrode sheets is a, 4 electrodes are pasted on each layer, the horizontal interval between each electrode is 90°, and the electrode numbers are A1, A2, A3...An respectively.

[0017] Preferably, in step S6, when the multi-electrode SIP measurement device collects data, firstly, A1 and A2 electrodes are used as power supply electrodes to supply currents of different frequencies, and A3, A4...An are used as measurement electrodes, and the measured impedance amplitude of each measurement frequency, the phase between the injection signal and the measurement signal, and their respective errors are recorded; after the measurement, A2 and A3 are used as power supply electrodes to supply currents of different frequencies, and A4, A5...An are used as measurement electrodes, and the measured impedance amplitude of each measurement frequency, the phase between the injection signal and the measurement signal, and their respective errors are recorded;

[0018] And so on, until An-3 and An-2 are used as power supply electrodes, An-1 and An are used as measurement electrodes, and the measured impedance amplitude, the phase between the injection signal and the measurement signal, and their respective errors are recorded for each measurement frequency.

[0019] Preferably, in step S7, the complex conductivity formula is as follows:

[0020]

[0021] Where: * (f) is the complex conductivity, σ'(f) is the real part, σ”(f) is the imaginary part, (f) is the frequency, is the phase; the real part of the complex conductivity represents the conductive properties of the mineral, and the imaginary part represents the polarizability of the mineral.

[0022] Therefore, the present invention adopts the above-mentioned method for determining the distribution characteristics of metal minerals in coal based on spectral induced polarization method, which can effectively establish the response relationship between the carrier minerals of strategic metals in coal and geophysical parameters.

[0023] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a flow chart of a method for determining the distribution characteristics of metal minerals in coal based on spectrum induced polarization method of the present invention;

[0025] Figure 2 It is a schematic diagram of a multi-electrode SIP measuring device of an embodiment of a method for determining the distribution characteristics of metal minerals in coal based on spectrum induced polarization method of the present invention;

[0026] Figure 3 It is a schematic diagram of phase parameter settings of a multi-electrode SIP measurement device according to an embodiment of a method for determining distribution characteristics of metal minerals in coal based on spectrum induced polarization method of the present invention;

[0027] Figure 4 It is a schematic diagram of setting conductivity parameters of a multi-electrode SIP measuring device according to an embodiment of a method for determining distribution characteristics of metal minerals in coal based on spectrum induced polarization method of the present invention;

[0028] Figure 5 This is a diagram of the inversion results of a multi-electrode SIP measurement device in an embodiment of a method for determining the distribution characteristics of metal minerals in coal based on the spectrum induced polarization method of the present invention. DETAILED DESCRIPTION

[0029] The technical solution of the present invention is further described below through the accompanying drawings and embodiments.

[0030] Unless otherwise defined, the technical terms or scientific terms used in the present invention should be understood by people with ordinary skills in the field to which the present invention belongs. The words "first", "second" and similar words used in the present invention do not indicate any order, quantity or importance, but are only used to distinguish different components. "Include" or "comprise" and similar words mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. "Connect" or "connected" and similar words are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0031] Embodiment 1

[0032] like Figure 1 As shown, the present invention provides a method for determining the distribution characteristics of metal minerals in coal based on spectrum induced polarization method (the English abbreviation of spectrum induced polarization method is SIP), comprising the following steps:

[0033] S1. Select the study area and collect samples.

[0034] After selecting a research area, samples are collected and 3-5 typical coal seam profiles are selected. When sampling, several block coal layers, interlayers, roof and floor samples are taken in sequence from top to bottom of the coal seam profile at the same intervals.

[0035] S2. Pre-process the collected samples by sorting, crushing and grinding.

[0036] S3. X-ray powder diffraction (XRD) method is used to qualitatively characterize the minerals in the sample. On this basis, the Siroquant mineral quantitative analysis system is used to quantitatively characterize the minerals in the sample.

[0037] S4. Classify the samples according to the metal mineral content test results of each sample.

[0038] S5. Process the sample into a multi-electrode SIP measurement device.

[0039] Specifically, the lump coal sample is processed into a cylindrical standard test sample with a diameter of 5 cm and a height of 10 cm. Electrode sheets are evenly spaced on the test sample. The longitudinal interval of the electrode sheets is 2 cm. Four electrodes are pasted on each layer. The horizontal interval between each electrode is 90°. The electrode numbers are 1, 2, 3...23, 24, respectively. Figure 2 To verify the effectiveness of this method, a random distribution model of metal minerals in coal was established. The phase parameters and conductivity parameters in the model are shown in Figure 3 and Figure 4 shown.

[0040] S6. Sequentially use two adjacent electrodes in the multi-electrode SIP measurement device as power supply electrodes, and the electrode behind them as a measurement electrode to measure the impedance amplitude Ω, the phase between the injection signal and the measurement signal and their respective errors.

[0041] When performing data acquisition of a multi-electrode SIP measurement device, specifically, firstly, electrodes 1 and 2 are used as power supply electrodes to be supplied with currents of different frequencies, and electrodes 3, 4, 23, and 24 are used as measurement electrodes, such as Figure 2 As shown in (b), the measured impedance amplitude at each measurement frequency, the phase between the injection signal and the measurement signal, and their respective errors are recorded. After the measurement, electrodes 2 and 3 are used as power supply electrodes to be supplied with currents of different frequencies, and electrodes 4, 5...23, and 24 are used as measurement electrodes. The measured impedance amplitude at each measurement frequency, the phase between the injection signal and the measurement signal, and their respective errors are recorded.

[0042] This is repeated until electrodes 21 and 22 are used as power supply electrodes and electrodes 23 and 24 are used as measurement electrodes, and the measured impedance amplitude, the phase between the injection signal and the measurement signal, and their respective errors are recorded at each measurement frequency.

[0043] S7. Calculate the complex conductivity of the collected SIP data. The complex conductivity formula is as follows:

[0044]

[0045] Where: * (f) is the complex conductivity, σ'(f) is the real part, σ”(f) is the imaginary part, (f) is the frequency, is the phase; the real part of the complex conductivity represents the conductive properties of the mineral, and the imaginary part represents the polarizability of the mineral.

[0046] S8. By inversion analysis of SIP data, the electrical response and distribution characteristics of metal minerals in coal are obtained, such as Figure 5 As shown, (a) is the amplitude inversion result of the transmission impedance, (b) is the real part inversion result of the complex conductivity, and (c) is the inversion result of the multi-electrode SIP measurement device.

[0047] Therefore, the present invention adopts the above-mentioned method for determining the distribution characteristics of metal minerals in coal based on spectral induced polarization method, which can effectively establish the response relationship between the carrier minerals of strategic metals in coal and geophysical parameters.

[0048] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that they can still modify or replace the technical solution of the present invention with equivalents, and these modifications or equivalent replacements cannot cause the modified technical solution to deviate from the spirit and scope of the technical solution of the present invention.

Claims

1. A method for determining the distribution characteristics of metal minerals in coal based on spectrum induced polarization method, characterized in that: The following steps are involved: S1. Select the study area and collect samples; S2, pre-processing the collected samples by sorting, crushing and grinding; S3, using X-ray powder diffraction method to qualitatively analyze the minerals in the sample, and then using Siroquant mineral quantitative analysis system to quantitatively analyze the minerals in the sample; S4. Classify the samples according to the metal mineral content test results of each sample; S5, processing the sample into a multi-electrode SIP measurement device; In step S5, the lump coal sample is processed into a cylindrical standard test sample with a radius of r and a height of h, and then an electrode sheet is attached to the test sample; Electrode sheets are pasted on the test sample at the same interval. The longitudinal interval of the electrode sheets is a. Four electrodes are pasted on each layer. The horizontal interval between each electrode is 90°. The electrode numbers are A1, A2, A3...An respectively. S6. Sequentially use two adjacent electrodes in the multi-electrode SIP measurement device as power supply electrodes, and the electrode behind them as a measurement electrode to measure the impedance amplitude Ω, the phase between the injection signal and the measurement signal and their respective errors; When collecting data for the multi-electrode SIP measurement device, firstly, the A1 and A2 electrodes are used as power supply electrodes and supplied with currents of different frequencies, and A3, A4...An are used as measurement electrodes, and the measured impedance amplitude, the phase between the injection signal and the measurement signal, and their respective errors are recorded for each measurement frequency. After the measurement, A2 and A3 are used as power supply electrodes and supplied with currents of different frequencies, and A4, A5...An are used as measurement electrodes, and the measured impedance amplitude, the phase between the injection signal and the measurement signal, and their respective errors are recorded for each measurement frequency. And so on, until An-3 and An-2 are used as power supply electrodes, An-1 and An are used as measurement electrodes, and the measured impedance amplitude, the phase between the injection signal and the measurement signal, and their respective errors are recorded for each measurement frequency; S7, calculating the complex conductivity of the collected SIP data; In step S7, the complex conductivity formula is as follows: ； Where: is the complex conductivity, is the real part, is the imaginary part, is the frequency, is the phase; the real part of the complex conductivity represents the conductivity of the mineral, and the imaginary part represents the polarizability of the mineral; S8. By inversion analysis of SIP data, the electrical response and distribution characteristics of metal minerals in coal are obtained.

2. The method for determining the distribution characteristics of metal minerals in coal based on spectrum induced polarization method according to claim 1, characterized in that: In step S1, 3-5 typical coal seam profiles are selected, and when sampling, a number of blocky coal layers, interlayered gangue, roof and floor samples are taken in sequence from top to bottom of the coal seam profile at the same intervals.

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