Block metal ore grade online analysis method based on high-voltage pulse discharge breakdown spectroscopy

Abstract

The invention provides a bulk metal ore grade online analysis method based on high-voltage pulse discharge breakdown spectroscopy, which comprises the following steps: (a) placing bulk metal ore particles in a high-voltage discharge electrode system filled with a liquid insulating medium, and applying 30-250kV voltage through a high-voltage electric pulse generator to carry out pulse discharge, carrying out electric breakdown on the ore particles and generating plasmas; (b) synchronously acquiring a plasma characteristic spectrum signal and a voltage waveform signal and a current waveform signal of pulse discharge in the electric breakdown process; (c) preprocessing the characteristic spectral signal, determining element types according to the wavelength of a characteristic spectral line, and extracting the intensity of the characteristic spectral line; and (d) inputting the characteristic spectral line intensity, the pulse discharge waveform parameter, the discharge condition and the ore particle property into a pre-established quantitative analysis model, and outputting the metal element grade of the ore particles.

Description

Technical Field

[0001] The present invention belongs to the technical field of mineral processing analysis, and in particular relates to an online analysis method for the grade of bulk metal ore based on high-voltage pulse discharge breakdown spectroscopy. Background Art

[0002] In mineral processing plants that extract and enrich metal minerals from ore, the metal grade of the feed ore is a key production monitoring indicator, directly impacting the plant's final output. However, in the non-ferrous metals sector, mineral processing plants currently lack effective online analysis methods for feed ore metal grade. X-ray fluorescence spectrometry (XRF) is a common online method for measuring ore metal grade in non-ferrous metal processing plants. XRF uses primary X-rays to excite atoms in the sample, generating characteristic X-rays. The wavelength or energy characteristics of these X-rays are then used to measure the types and concentrations of various elements in the sample. Because XRF has a detection range of only 1 nanometer to 50 microns, it can only be used for online analysis of the metal grade of powdered final products or for obtaining surface metal grade data from bulk feed ore particles. It cannot directly analyze the metal grade of bulk feed ore.

[0003] High-voltage electric pulse crushing is a technology that uses a high-voltage pulsed electric field to cause electrical breakdown in materials. When ore is crushed with high-voltage electric pulses, the metal mineral grains within the ore particles induce electrical breakdown. Plasma discharge channels preferentially develop along the surfaces of the metal mineral grains, leading to electrical breakdown. Ore particles selectively break along the surfaces of the metal mineral grains under the tensile stress created by the expansion of the discharge channels. During the electrical breakdown process, the presence of the metal minerals affects the voltage and current waveforms of the pulse discharge. Furthermore, during the electrical breakdown process, the components of the metal mineral grains are converted into plasma. Subsequently, as the plasma cools, excited atoms transition to lower energy levels, resulting in intense luminescence. Summary of the Invention

[0004] To address the technical deficiencies of existing technologies, such as the difficulty of directly analyzing the grade of bulk ore online in mineral processing plants and the inability of X-ray fluorescence spectroscopy (XRF) to accurately detect light elements, this invention provides an online analysis method for the grade of bulk metal ores based on high-voltage pulsed discharge breakdown spectroscopy. This method directly breaks down bulk ore particles by applying a 30-250 kV high-voltage pulse. During this electrical breakdown process, plasma is simultaneously excited and characteristic spectral signals are collected. The voltage and current waveforms of the pulsed discharge are also captured, enabling integrated ore crushing and detection, completely eliminating the tedious crushing and grinding steps required for traditional sample preparation.

[0005] At the signal processing level, the collected spectral signals undergo mean-centering preprocessing to eliminate baseline interference. The elemental identity and intensity data are then determined based on the wavelength of the characteristic spectral lines. Key parameters such as breakdown delay and channel resistance are extracted from the discharge waveform and combined with physical properties such as ore particle size and porosity to form a quantitative analysis model constructed using a support vector machine. This model, trained on samples of similar ores of known grade, accurately outputs the metal element grade of bulk ore. Innovatively, the characteristic spectrum includes spectral lines for light elements with atomic numbers 10-20, overcoming the limitations of XRF technology in detecting light elements.

[0006] To achieve industrial application, this method uses a needle-plate electrode and a water-medium gap to coordinately control the discharge path (the electrode spacing ranges from 10 to 100 mm, with 40 mm being the preferred value in experiments). Furthermore, a multi-particle, multi-discharge mode is employed to enhance analytical efficiency. Experiments demonstrate that the model's predictions are highly consistent with standard detection methods (such as ICP-MS) (R² > 0.89), validating the reliability of the method.

[0007] Ultimately, this method can be directly integrated into the belt conveyor system of the mineral processing plant, and block ore samples can be intercepted in real time through flowing material sampling, realizing the onlineization of the entire process from sampling, analysis to result output, providing an efficient solution for ore grade monitoring.

[0008] The technical solution specifically adopted by the present invention to solve the technical problem is: A method for online analysis of bulk metal ore grade based on high-voltage pulse discharge breakdown spectroscopy comprises the following steps: (a) Lumpy metal ore particles are placed in a high-voltage discharge electrode system filled with a liquid insulating medium. A high-voltage electric pulse generator applies a voltage of 30 to 250 kV to perform pulse discharge, causing electrical breakdown of the ore particles and generating plasma. (b) synchronously collecting characteristic spectrum signals of the plasma during the electrical breakdown process and voltage waveform signals and current waveform signals of the pulse discharge; (c) preprocessing the characteristic spectral signal, determining the element type based on the characteristic spectral line wavelength, and extracting the characteristic spectral line intensity; (d) inputting the characteristic spectral line intensity, pulse discharge waveform parameters, discharge conditions and ore particle properties into a pre-established quantitative analysis model to output the metal element grade of the ore particles; The quantitative analysis model is based on samples of the same type of ore with known elemental grades, and is established by correlating characteristic spectral line intensity, pulse waveform parameters, discharge conditions, ore properties and elemental grade data; The pulse discharge waveform parameters include at least one of breakdown delay, breakdown voltage, current maximum, channel voltage maximum, inductance, total work, key stage work or breakdown channel average resistance.

[0009] Based on the above scheme, the plasma discharge channel is preferentially developed along the surface of the metal mineral grains inside the ore particles during the electrical breakdown process.

[0010] Furthermore, the liquid insulating medium is deionized water, and its conductivity is less than 60 μS / cm.

[0011] Furthermore, the high-voltage discharge electrode system adopts needle-plate electrodes with an electrode spacing of 10-100 mm; the discharge electrode is a needle electrode, the grounding electrode is a plate electrode, and the electrodes are made of a material that does not contain the metal element to be measured.

[0012] Furthermore, the discharge voltage of the pulse discharge is 90~200kV, and is determined based on a breakdown probability model, so that the probability of electrical breakdown of the ore particles is not less than 95%, wherein the breakdown probability model is established through predictive tests of the same type of ore, characterizing the relationship between the increase in breakdown probability with increasing discharge voltage.

[0013] Furthermore, the spectrum preprocessing adopts the adaptive penalty least squares baseline removal method to eliminate the interference of spectrum baseline drift; The characteristic spectrum includes characteristic spectral lines of light elements with atomic numbers of 10-20.

[0014] Furthermore, the ore particle properties include at least two of particle size, porosity and particle shape.

[0015] Furthermore, the quantitative analysis model is constructed using a support vector machine algorithm.

[0016] Furthermore, the pulse discharge waveform parameters associated with modeling include breakdown delay and average breakdown channel resistance, the values ​​of which are determined based on real-time analysis of the voltage / current waveform by the signal processor, wherein: Breakdown delay refers to the time from when the voltage rises to 10% of the peak value to when electrical breakdown occurs; The average resistance of the breakdown channel is determined by the average value of the ratio of the effective voltage to the current after the electrical breakdown occurs.

[0017] Furthermore, the detection of incoming ore applied to the belt conveyor of the mineral processing plant includes: Use the flowing material sampling method to intercept the block ore samples; Perform steps (a)-(d) directly on the sample and output the grade results to the concentrator control system in real time.

[0018] Compared with the prior art, the present invention and its preferred embodiments have at least the following beneficial effects: 1. Breakthrough in the direct detection bottleneck of lump ore: Through high-voltage pulse discharge, integrated crushing and detection are achieved, eliminating the traditional crushing and sample preparation process, overcoming the industry's difficulty that technologies such as XRF cannot directly analyze bulk ores, and significantly improving online detection efficiency.

[0019] 2. Expand the detection range of elements: The plasma spectrum excited by discharge is used to cover the characteristic spectral lines of light elements with atomic numbers 10-20, making up for the detection defects of light elements in existing technologies and achieving more comprehensive elemental composition analysis.

[0020] 3. Improve detection accuracy and reliability: The spectral signal is synchronously integrated with electrical parameters (breakdown delay, channel resistance, etc.), and a multivariate model is constructed in combination with the physical properties of the ore to accurately reflect the mineral occurrence status inside the ore and effectively reduce analytical errors.

[0021] 4. Strengthen industrial adaptability: The coordinated design of the gap between the needle-plate electrode and the aqueous medium optimizes the discharge path, supports flexible adjustment of the electrode spacing from 10 to 100 mm, and ensures stable breakdown of ores of different particle sizes; the optimized adaptive penalty least squares baseline removal method effectively suppresses spectral baseline drift interference and ensures signal quality under complex working conditions.

[0022] 5. Realize the whole process online: It supports direct sampling and real-time analysis on the belt conveyor of the mineral processing plant, forming a closed loop of "sampling-crushing-detection-output", providing instant data support for production control, and completely solving the lag problem of traditional offline detection. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The present invention is further described in detail below with reference to the accompanying drawings and specific embodiments: Figure 1 This is a schematic structural diagram of a device for performing high-voltage electric pulse crushing on a mineral sample to be tested according to an embodiment of the present invention; Figure 2 This is a comparison chart of the lead (Pb) element grade of the feed ore of the lead ore concentrator according to an embodiment of the present invention; Figure 3 This is a diagram showing the core steps of the method according to an embodiment of the present invention; Figure 4 It is a roadmap for implementing the complete solution of the embodiment of the present invention. DETAILED DESCRIPTION

[0024] In order to make the features and advantages of the present invention more clearly understood, the following embodiments are given for detailed description: It should be noted that the following detailed descriptions are exemplary and are intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used in this specification have the same meanings as those commonly understood by those skilled in the art to which this application belongs.

[0025] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, they indicate the presence of features, steps, operations, devices, components and / or combinations thereof.

[0026] The present invention considers spectral analysis of the luminescence phenomenon caused by the fragmentation of high-voltage electric pulses and discovers that the characteristics of metal minerals can be manifested in the form of characteristic spectral lines in the spectrum. Since each element's atoms produce a characteristic spectrum upon excitation, and the wavelengths of the characteristic spectral lines vary for different elements, the presence of a particular element can be determined based on the wavelength of the characteristic spectral lines, enabling qualitative analysis of the elemental composition of the metal mineral. Furthermore, within a certain range, the intensity of the spectral lines emitted by a particular element is correlated with factors such as the voltage and current waveforms of the pulse discharge, the discharge conditions, and the properties of the ore particles themselves. Leveraging this correlation, a predictive model for the type and content of metal elements in bulk ore particles can be established. The advantage of this technology is that it fully utilizes the inductive effect of metal minerals on electrical breakdown channels. Because plasma discharge channels preferentially develop along the surfaces of metal mineral grains within ore particles, the characteristic spectra of the plasma discharge channels and the pulse discharge voltage and current waveforms can reflect information about the occurrence state of the metal minerals within the ore particles, making this technology naturally suitable for elemental analysis of bulk ore particles. Compared with XRF technology, the metal ore grade analysis method based on high-voltage pulse discharge breakdown spectroscopy does not require the bulk ore particles to be prepared into powder. Instead, the bulk ore can be directly crushed by high-voltage electric pulses. By collecting and processing the light and electrical signals during the electric breakdown process, the metal element analysis results inside the bulk ore particles can be quickly obtained. This method is suitable for application scenarios such as online analysis of metal elements in feed ore of mineral processing plants.

[0027] To this end, the present invention proposes a method for elemental composition analysis of bulk metal ores based on high-voltage pulse discharge breakdown spectroscopy, such as Figure 3 As shown: When using the invention to analyze the grade of ore, it is necessary to first establish a mathematical model for the specific ore type for correction. First, the selected metal ore particles are crushed by high-voltage electric pulses, and the voltage and current waveforms of each pulse discharge and the characteristic spectrum of the plasma discharge channel are collected. The collected characteristic spectrum data needs to be preprocessed before use. According to the different wavelengths of the characteristic spectrum curves of different elements, the elements contained in the ore to be tested are matched one by one with their characteristic wavelengths. Then, conventional ore element analysis methods are used to determine the elemental composition of the high-voltage electric pulse crushing product, and then statistical regression analysis or machine learning are used to establish a mathematical model of the "metal element content of ore particles" and its corresponding "characteristic peak intensity of the spectrum curve". The modeling process needs to take into account the influence of the voltage and current waveform of the pulse discharge, as well as the discharge conditions and the properties of the ore particles themselves.

[0028] After modeling is complete, this method can be used to perform elemental analysis on metal ore particles of unknown grade. After the ore particles are subjected to high-voltage electric pulses, the mineral's characteristic spectrum curve is collected using a spectrometer. The metal element type is first qualitatively analyzed based on the wavelength of the characteristic spectrum line. Then, data such as the characteristic spectrum line intensity, pulse discharge waveform, discharge conditions, and the properties of the ore particles are input into the model to calculate the metal element composition of the ore particles.

[0029] The specific technical solutions provided by the embodiments of the present invention are as follows: As a preferred solution of this embodiment, high voltage pulse discharge on ore can be performed using, but not limited to: rod-plate electrodes, parallel plate electrodes, concentric ring electrodes, same-side rod electrodes, different-rod needle electrodes, etc. A more optimal option is a needle-plate electrode system, where the discharge electrode is a needle electrode and the ground electrode is a plate electrode. The electrodes are made of a material that does not contain the metal element to be measured in the ore. Depending on the type of valuable metal elements in the ore, the electrodes can be made of tungsten (alloy), molybdenum (alloy), copper (alloy), or stainless steel.

[0030] As a preferred embodiment of this embodiment, the pulse waveform parameters of the particle electric pulse fragmentation process refer to a series of key parameters calculated based on the voltage and current waveforms, including but not limited to: breakdown delay, breakdown voltage, current maximum value, channel voltage maximum value, inductance, total work, work done in key stages, and average resistance of the breakdown channel; As a preferred solution of this embodiment, the discharge conditions referred to are: discharge voltage, voltage rise rate, energy storage capacitance, electrode spacing, water gap between electrode and ore, circuit inductance, circuit resistance, etc.; As a preferred embodiment of this embodiment, the properties of the ore particles include but are not limited to: particle size, particle shape, particle density, particle porosity, particle surface roughness, preliminary mineral composition obtained based on particle surface information, etc.; As a preferred solution of this embodiment, the spectrum preprocessing methods referred to include but are not limited to: mean centering, normalization, smoothing and denoising, baseline correction, derivative enhancement, scatter correction, feature dimensionality reduction, peak position correction, standardization, Savitzky–Golay filtering, wavelet transform, adaptive penalized least squares baseline removal, derivative transform, principal component analysis, etc.; As a preferred solution of this embodiment, the spectral quantitative analysis modeling method referred to includes but is not limited to: multiple linear regression, partial least squares regression, principal component regression, support vector machine, free calibration method, random forest regression, gradient boosting regression tree, artificial neural network, convolutional neural network, deep neural network, etc.

[0031] In this embodiment, for a specific ore type, the main mineral types and element types contained in the ore particles are known in advance; Prepare discharge electrodes and a high-voltage electric pulse generator according to the selected electrode type and electrode spacing (generally between 10 mm and 100 mm); The ore is crushed to a particle size suitable for being processed by the prepared discharge electrodes, and the particle size distribution and shape characteristics of the ore particles are determined by mechanical screening or image recognition.

[0032] As a preferred embodiment, the ore sample can be washed and sieved to remove fine particles before testing to further improve the detection effect, and the sieve aperture is selected within the range of 10 to 15 mm.

[0033] High-voltage electric pulse crushing treatment is performed on the ore sample to be tested. When the object of each discharge treatment is a single ore particle, the single-particle single-pulse discharge treatment mode is preferably adopted, but the single-particle multiple-pulse discharge treatment mode can also be adopted; when the object of each discharge treatment is a particle group composed of multiple ore particles, the multiple-particle multiple-pulse discharge treatment mode is preferably adopted, but the multiple-particle single-pulse discharge treatment mode can also be adopted.

[0034] like Figure 1 As shown, the ore particle sample 1 to be tested is placed between the discharge electrode 2 and the ground electrode 3. An appropriate amount of water is placed between the discharge electrode and the ground electrode, acting as an insulating medium. When using the single-particle pulse crushing mode, only one ore particle is placed between the discharge electrode and the ground electrode, ensuring that the particle is positioned as close to the center of the discharge electrode as possible. When using the multi-particle pulse crushing mode, a certain number of ore particles are placed between the discharge electrodes, ensuring that the surface of the highest particle layer of the particle group is relatively flat.

[0035] As a better option, deionized water can also be used as the insulating medium. The conductivity of deionized water should be kept below 60μS / cm. This option can significantly improve the discharge stability.

[0036] A high-voltage pulse generator 4 connects the discharge electrode 2 to the ore particle sample 1 to be tested, generating a pulse discharge. The ground electrode 3, located at the bottom of the ore particle sample, acts as a counter electrode during the pulse discharge process. The distance between the discharge electrode and the ground electrode is the electrode spacing. The number of discharges is adjusted using the high-voltage pulse generator 4. The voltage range is 30–250 kV, and the single pulse energy range is 50–2000 J.

[0037] The more preferred discharge voltage is 90-200 kV, and the specific value principle is that it should be no less than the breakdown voltage of 95% of the ore particles at a specific electrode spacing. The discharge voltage and the probability of electrical breakdown of the ore particles can be expressed by the following formula: Where F is the probability of electrical breakdown of an ore particle, U is the discharge voltage, U0 is the minimum breakdown voltage for that type of ore particle, and a is a constant. For a specific type of ore, the value of constant a is determined through testing. This formula is then used to determine the discharge voltage, which must be no less than the voltage that causes electrical breakdown in 95% of the ore particles.

[0038] The current waveform of each pulse discharge is detected by the pulse current detector 5, the voltage waveform of each pulse discharge is detected by the voltage divider 6 and the high-frequency high-voltage probe 7, and the collected pulse waveform is recorded and processed by the signal processor 9.

[0039] The optical signal released by the plasma during the electrical breakdown of the ore particle sample 1 to be tested is collected by the spectrometer 8, and the optical signal is finally transmitted to the signal processor 9 through the interface for analysis.

[0040] Because the initial spectral data obtained has high dimensionality and a large number of spectral lines, and there is a considerable degree of spectral overlap and interference, it will increase the analysis time and increase the intensity of the analysis lines, thereby affecting the analysis efficiency and the accuracy of the results. Therefore, it is necessary to use spectral preprocessing methods to preprocess the obtained spectral data.

[0041] After the spectral data preprocessing is completed, the elements contained in the ore particle sample to be tested are matched one by one to their characteristic wavelengths according to the different wavelengths of the characteristic spectral curves of different elements, thereby completing the qualitative analysis.

[0042] In this embodiment, conventional laboratory methods are used to obtain the content of the elements to be measured in the above-mentioned ore particles, which serves as a calibration benchmark for subsequent modeling.

[0043] Through statistical regression analysis or machine learning combined with spectral quantitative analysis modeling, a mathematical model is established to link the elemental grade of the ore particle sample to its corresponding peak-to-peak intensity of the spectral curve. This modeling process takes into account the influence of the pulse discharge voltage and current waveform, discharge conditions, and the properties of the ore particles themselves. Calibration is then performed for the specific type of ore particle sample.

[0044] After modeling is complete, the method provided in this example can be used to perform elemental analysis on metal ore particles of unknown grade. After the unknown grade metal ore particles are subjected to high-voltage electric pulses, the characteristic spectral curve of the mineral is collected using a spectrometer. The type of metal element is first qualitatively analyzed based on the wavelength of the characteristic spectral line. Then, data such as the intensity of the characteristic spectral line, the pulse discharge waveform, discharge conditions, and the properties of the ore particles are input into the model to calculate the metal element composition of the ore particles.

[0045] Compared with the prior art, the specific advantages of the solution provided by the embodiments of the present invention are as follows: (1) The present invention has the advantage of integrated crushing and detection. Compared with conventional laboratory detection methods, the present invention can eliminate the tedious sample preparation work such as crushing, grinding, and reduction for elemental analysis of bulk ore, thereby achieving the purpose of online detection of the elemental composition of bulk metal ore. (2) Because the plasma emission spectrum excited by high-voltage pulse discharge contains the characteristic spectral lines of most elements (including light elements with atomic numbers between 10 and 20), the present invention makes up for the defect that XRF technology is difficult to accurately determine light elements, and realizes the simultaneous determination of more elements.

[0046] like Figure 4 As shown, the present invention can directly and quickly detect the internal element content of bulk metal ore, and is suitable for online detection of the grade of feed ore in a mineral processing plant, as well as for scenarios requiring large-scale rapid detection, such as geological and metallurgical research.

[0047] To further demonstrate and introduce the solution provided by the embodiment of the present invention, the feed ore of a lead ore dressing plant is used as an experimental sample, and the elemental composition of the metal ore is detected using the solution provided in the embodiment above.

[0048] 1) Sampling: First, using the flowing material sampling method, samples were collected from the belt conveyor that transports the incoming ore at the lead ore processing plant. Next, using the transverse interception method, small amounts of material were sampled perpendicular to the flow of the material on the belt conveyor every five minutes. These individual samples were then accumulated to form the total sample.

[0049] 2) All ore samples obtained from the lead ore concentrator were crushed to a particle size of less than 40 mm. The particle size distribution of all crushed samples was determined by mechanical screening. A rotary divider was used to randomly divide the crushed samples into several portions, each weighing 700 g. A total of 105 experimental subsamples were obtained, 45 of which were used as experimental sample 1 for the initial modeling of the present invention, and the remaining 60 were used as experimental sample 2 for subsequent testing of the actual effectiveness of the present invention.

[0050] 3) Select a needle-plate electrode as the discharge electrode for the experiment, control the electrode spacing to 40 mm, and prepare experimental equipment such as a high-voltage electric pulse generator.

[0051] 4) Place each experimental sample sequentially into a conical electrode barrel, ensuring that the particle layer surface of each sample is relatively flat. Fill the barrel with an appropriate amount of water, which acts as an insulating medium. The experiment utilizes a multi-particle, multi-pulse discharge process, setting the charge voltage to 150 kV and discharging each sample 10 times.

[0052] 5) The voltage and current waveforms of each pulse discharge are detected by a waveform detection device, and the optical signals released by the plasma during the electrical breakdown of the ore particle sample are collected by a spectrometer. Finally, the collected data are transmitted to the computer through an interface for analysis.

[0053] 6) The obtained spectral data are preprocessed using the spectral preprocessing method of adaptive penalized least squares baseline removal.

[0054] 7) The spectral peak intensity of the characteristic wavelength of 405.780 nm, the main element Pb in the experimental sample, is determined through the preprocessed spectral data.

[0055] 8) Inductively coupled plasma mass spectrometry (ICP-MS) was used to obtain the lead (Pb) element grade of the above experimental samples as a reference for subsequent modeling.

[0056] 9) Use the spectral data of samples with known lead (Pb) grade, as well as the voltage and current waveforms of each pulse discharge, discharge conditions, and the properties of the ore particles themselves as the training set to train the support vector machine (SVM) model.

[0057] 10) Repeat the above steps for 60 samples of experimental sample 2, and bring the relevant data indicators into the trained support vector machine (SVM) model to obtain the detection results of the high-voltage pulse discharge breakdown spectrum.

[0058] 11) The lead (Pb) element grade of the feed ore of the lead ore processing plant was compared by high voltage pulse discharge breakdown spectroscopy and inductively coupled plasma mass spectrometry (ICP-MS). Figure 2 shown.

[0059] 12) The values ​​of lead (Pb) element grade of the feed ore of the lead ore dressing plant detected by the two methods are statistically consistent, and their trend lines coincide with Y=X, R 2 The value is 0.8937, and the model fit is good.

[0060] Based on the same inventive concept, the present invention also provides a computer device, which includes: one or more processors and a memory for storing one or more computer programs; the program includes program instructions, and the processor is used to execute the program instructions stored in the memory. The processor may be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. It is the computing core and control core of the terminal, which is used to implement one or more instructions, specifically for loading and executing one or more instructions in a computer storage medium to implement the above method.

[0061] It should be further explained that, based on the same inventive concept, the present invention also provides a computer storage medium having a computer program stored thereon, which, when executed by a processor, performs the above-described method. The storage medium may be any combination of one or more computer-readable media. The computer-readable medium may be a computer-readable signal medium or a computer-readable storage medium. The computer-readable storage medium may be, for example, but not limited to, an electrical, magnetic, optical, infrared, or semiconductor system, apparatus, or device, or any combination thereof. More specific examples (a non-exhaustive list) of computer-readable storage media include: an electrical connection having one or more conductors, a portable computer disk, a hard disk, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination thereof. In the present invention, a computer-readable storage medium may be any tangible medium containing or storing a program that can be used by or in conjunction with an instruction execution system, apparatus, or device.

[0062] It should be noted that, unless otherwise defined, the technical or scientific terms used in the present invention should have the usual meanings understood by people with ordinary skills in the field to which the present invention belongs. The "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 object being described changes, the relative positional relationship may also change accordingly.

[0063] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any other manner. Any person skilled in the art may utilize the above-disclosed technical content to modify or modify the present invention into equivalent embodiments. However, any simple modifications, equivalent variations, and modifications to the above embodiments that do not depart from the technical content of the present invention and are based on the technical essence of the present invention remain within the scope of protection of the present invention.

[0064] The present invention is not limited to the above-mentioned optimal embodiment. Anyone can derive various other forms of an online analysis method for the grade of bulk metal ore based on high-voltage pulse discharge breakdown spectroscopy under the inspiration of the present invention. All equal changes and modifications made within the scope of the patent application of the present invention should fall within the scope of the present invention.

Claims

1. A bulk metal ore grade online analysis method based on high voltage pulse discharge breakdown spectroscopy, characterized in that: The following steps are involved: (a) Lumpy metal ore particles are placed in a high-voltage discharge electrode system filled with a liquid insulating medium. A high-voltage electric pulse generator applies a voltage of 30 to 250 kV to perform pulse discharge, causing electrical breakdown of the ore particles and generating plasma. (b) synchronously collecting characteristic spectrum signals of the plasma during the electrical breakdown process and voltage waveform signals and current waveform signals of the pulse discharge; (c) preprocessing the characteristic spectral signal, determining the element type based on the characteristic spectral line wavelength, and extracting the characteristic spectral line intensity; (d) inputting the characteristic spectral line intensity, pulse discharge waveform parameters, discharge conditions and ore particle properties into a pre-established quantitative analysis model to output the metal element grade of the ore particles; The quantitative analysis model is based on samples of the same type of ore with known elemental grades, and is established by correlating characteristic spectral line intensity, pulse waveform parameters, discharge conditions, ore properties and elemental grade data; The pulse discharge waveform parameters include at least one of breakdown delay, breakdown voltage, current maximum, channel voltage maximum, inductance, total work, key stage work or breakdown channel average resistance.

2. The method for online analysis of bulk metal ore grade based on high-voltage pulse discharge breakdown spectroscopy according to claim 1, characterized in that: The liquid insulating medium is water, and a water gap is formed between the electrode and the ore to control the discharge path.

3. The method for online analysis of bulk metal ore grade based on high-voltage pulse discharge breakdown spectroscopy according to claim 2, characterized in that: The liquid insulating medium is deionized water, and its conductivity is less than 60 μS / cm.

4. The method for online analysis of bulk metal ore grade based on high-voltage pulse discharge breakdown spectroscopy according to claim 1, characterized in that: The high-voltage discharge electrode system adopts needle-plate electrodes with an electrode spacing of 10-100 mm; the discharge electrode is a needle electrode, the grounding electrode is a plate electrode, and the electrodes are made of materials that do not contain the metal element to be measured.

5. The method for online analysis of bulk metal ore grade based on high-voltage pulse discharge breakdown spectroscopy according to claim 1, characterized in that: The discharge voltage of the pulse discharge is 90-200 kV, and is determined based on a breakdown probability model to ensure that the probability of electrical breakdown of the ore particles is not less than 95%. The breakdown probability model is established through predictive tests on the same type of ore, and characterizes the relationship in which the breakdown probability increases with increasing discharge voltage.

6. The method for online analysis of bulk metal ore grade based on high-voltage pulse discharge breakdown spectroscopy according to claim 1, characterized in that: The spectrum preprocessing adopts the adaptive penalty least squares baseline removal method to eliminate the interference of spectrum baseline drift; The characteristic spectrum includes characteristic spectral lines of light elements with atomic numbers of 10-20.

7. The method for online analysis of bulk metal ore grade based on high-voltage pulse discharge breakdown spectroscopy according to claim 1, characterized in that: The ore particle properties include at least two of particle size, porosity and particle shape.

8. The method for online analysis of bulk metal ore grade based on high-voltage pulse discharge breakdown spectroscopy according to claim 1, characterized in that: The quantitative analysis model is constructed using a support vector machine algorithm.

9. The method for online analysis of bulk metal ore grade based on high-voltage pulse discharge breakdown spectroscopy according to claim 1, characterized in that: The pulse discharge waveform parameters associated with modeling include breakdown delay and average breakdown channel resistance. The values ​​of the breakdown delay and average breakdown channel resistance are determined based on real-time analysis of the voltage / current waveform by the signal processor, where: Breakdown delay refers to the time from when the voltage rises to 10% of the peak value to when electrical breakdown occurs; The average resistance of the breakdown channel is determined by the average value of the ratio of the effective voltage to the current after the electrical breakdown occurs.

10. The method for online analysis of bulk metal ore grade based on high voltage pulse discharge breakdown spectroscopy according to claim 1, characterized in that: Applied to the incoming ore detection on the belt conveyor of the mineral processing plant, including: Use the flowing material sampling method to intercept the block ore samples; Perform steps (a)-(d) directly on the sample and output the grade results to the concentrator control system in real time.

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