Apparatus and method for ore analysis

Abstract

An apparatus for analyzing ore includes a pulsed X-ray source configured to irradiate ore material with a pulsed X-ray beam; a beam monitoring device including a scintillator that emits light when excited by the X-ray beam and a photomultiplier (PMT) that absorbs the light emitted by the scintillator and converts the absorbed light into an electrical output signal; a shutter selectively adjustable between an open configuration in which the X-ray beam impinges on the scintillator and a closed configuration in which the shutter substantially shields the X-ray beam from impinging on the scintillator; and a gain control device configured to control a gain of the PMT to a first gain when the shutter is in the open configuration and a second gain when the shutter is in the closed configuration, the second gain being higher than the first gain.

Description

Cross-references to related applications

[0001] This application claims priority to Australian Provisional Patent Application No. 2023901883, filed on 14 June 2023, the entire contents of which are incorporated herein by reference. Technical Field

[0002] This disclosure relates to material analysis using X-ray sources, and specifically, but not exclusively, to ore analysis as part of an ore sorting process. Background Technology

[0003] High-grade mineral deposits worldwide are dwindling, while the quality of new deposits is declining. This presents a challenge to the mining industry as demand for raw materials in ores increases. Selective mining and ore sorting attempt to address this problem by identifying ores with high levels of target elements through mineral analysis and separating them from waste ore in real time.

[0004] Mineral analysis typically aims to determine the concentration of a target element in an ore sample. This allows for the sorting of the ore material based on the determined concentration. However, mining equipment processes substantial quantities of material (e.g., thousands of tons per hour), therefore, effective mining equipment requires rapid analytical techniques capable of operating at high throughput rates with reliability and / or enhanced safety.

[0005] One method for analyzing elements in ores is based on activating the sample with high-energy X-rays, such as gamma activation analysis (GAA). In GAA, a high-energy X-ray source is used to irradiate and activate the ore sample, thereby inducing nuclear reactions in the target element within the sample. Subsequently, a detector measures the gamma radiation emitted by the radioactive decay of the activated sample to determine the concentration of the target element. By measuring the different energies of these emissions, different target elements can be identified.

[0006] Any discussion of documents, actions, materials, devices, articles, or the like included in this specification shall not be construed as an admission that any or all of these matters constitute part of the prior art or common knowledge in the field relating to this disclosure prior to the priority date of each appended claim. Summary of the Invention

[0007] In a first aspect, this disclosure provides an apparatus for analyzing ores, comprising:

[0008] A pulsed X-ray source configured to irradiate a mineral material with a pulsed X-ray beam; and

[0009] A beam monitoring device comprising a scintillator that emits light when excited by an X-ray beam and a photomultiplier tube (PMT) that absorbs the light emitted by the scintillator and converts the absorbed light into an electrical output signal.

[0010] The shutter is selectively adjustable between an open configuration and a closed configuration, wherein in the open position, the X-ray beam irradiates the scintillator, and in the closed configuration, the shutter essentially blocks the X-ray beam, preventing it from irradiating the scintillator;

[0011] A gain control device configured to control the gain of the PMT to a first gain when the shutter is in an open configuration and a second gain when the shutter is in a closed configuration, wherein the second gain is higher than the first gain.

[0012] The gain control device can be configured to control the gain of the PMT synchronously or cyclically with adjusting the shutter speed between the open and closed configurations.

[0013] The device may include a processor configured to monitor the stability of the pulsed X-ray beam based on a measurement of the voltage of the electrical output signal from the PMT when the shutter is in a closed configuration and the PMT gain is a second gain.

[0014] Pulsed X-ray sources may include rhodotrons. For example, the frequency of a pulsed X-ray source may be greater than 300 Hz or greater than 500 Hz.

[0015] The difference between the first gain and the second gain can be at least 1,000 times or at least 10,000 times. In some embodiments, the first gain, which is lower than the second gain, can be a non-zero gain or a zero gain.

[0016] The device may include an actuator configured to, for example, automatically and / or periodically adjust the shutter between an open configuration and a closed configuration. The actuator may include a mechanical actuator, such as a linear actuator or a rotator, which may be moved, for example, by the action of a motor. Alternatively, the shutter may be an electrically controlled electro-optical shutter.

[0017] The gain control device can control the voltage of the electrical signal supplied to the PMT and / or can control the switching of the PMT's multiplier poles to control the gain between a first gain and a second gain. The gain control device may include, for example, a switching voltage divider circuit, which can provide, for example, a switching voltage divider base for the PMT.

[0018] The device may include a controller configured to control at least one of the following: adjusting the shutter speed between an open configuration and a closed configuration; and controlling the gain of the PMT between a first gain and a second gain.

[0019] The shutter may contain bismuth. In some embodiments, the device may include a shield between the X-ray source and the scintillator, wherein the shield reduces the intensity of the pulsed X-ray beam irradiating the scintillator. The shield may contain bismuth.

[0020] The scintillator of a beam monitoring device may contain bromine.

[0021] The device may include at least one detector to monitor emitted radiation from the ore material in response to irradiation of the ore material by a pulsed X-ray beam. The detector may include, for example, a lanthanum bromide scintillator.

[0022] The processor can be configured to determine a correction factor based on a measurement of the voltage of the electrical output signal from the PMT, and to correct the signal from the detector based on that correction factor. The electrical output signal from the PMT can vary over time based on one or more parameters of the pulsed X-ray beam irradiating the scintillator of the beam monitoring device, such as energy, intensity, frequency, duty cycle, and / or angular distribution. Variations in any one or more of these parameters, and potentially others, can alter the amount of energy absorbed by the scintillator, and the determined correction factor can therefore account for variations in one or more of these parameters. Since the parameters of the pulsed X-ray beam can vary over time, and therefore may differ when the X-ray beam irradiates different blocks or sections of ore material, different correction factors can be determined and used to correct the signal from the detector corresponding to the emitted radiation from different blocks or sections of ore material.

[0023] The apparatus may include at least one conveyor belt on which a mineral material irradiated by a pulsed X-ray beam is located. The mineral material may move along the at least one conveyor belt between an irradiation area and a detection area, in which the mineral material is irradiated by the pulsed X-ray beam, and in the detection area, the emitted radiation from the mineral material in response to the irradiation is monitored.

[0024] According to a second aspect of this disclosure, a method for analyzing ore is provided, comprising:

[0025] Irradiate the mineral material with a pulsed X-ray beam from a pulsed X-ray source;

[0026] A beam monitoring device is provided, comprising a scintillator that emits light when excited by an X-ray beam and a photomultiplier tube (PMT) that absorbs the light emitted by the scintillator and converts the absorbed light into an electrical output signal.

[0027] The shutter speed is selectively adjusted between an open configuration and a closed configuration, wherein in the open position, the X-ray beam irradiates the scintillator, and in the closed configuration, the shutter essentially blocks the X-ray beam, preventing it from irradiating the scintillator; and

[0028] The gain of the PMT is controlled as a first gain when the shutter is in the open configuration and a second gain when the shutter is in the closed configuration, with the second gain being higher than the first gain.

[0029] The second aspect of the method may utilize the device according to the first aspect and / or may perform steps described with respect to one or more features of the device according to the first aspect.

[0030] According to a third aspect, this disclosure provides an apparatus for analyzing ores, comprising:

[0031] A pulsed X-ray source configured to irradiate a mineral material with a pulsed X-ray beam; and

[0032] A beam monitoring device comprising a scintillator that emits light when excited by an X-ray beam and an optoelectronic device that absorbs the light emitted by the scintillator and converts the absorbed light into an electrical output signal;

[0033] A shutter that can be selectively adjusted between an open configuration and a closed configuration, wherein in the open position, the X-ray beam irradiates the scintillator, and in the closed configuration, the shutter substantially blocks the X-ray beam, preventing it from irradiating the scintillator; and

[0034] The processor is configured to monitor the stability of the pulsed X-ray beam based on a measurement of the voltage of the electrical output signal from the photoelectric device when the shutter is in a closed configuration.

[0035] According to the fourth aspect, this disclosure provides a method for analyzing ore, comprising:

[0036] Irradiate the mineral material with a pulsed X-ray beam from a pulsed X-ray source;

[0037] A beam monitoring device is provided, comprising a scintillator that emits light when excited by an X-ray beam and a photoelectric device that absorbs the light emitted by the scintillator and converts the absorbed light into an electrical output signal;

[0038] The shutter speed is selectively adjusted between an open configuration and a closed configuration, wherein in the open position, the X-ray beam irradiates the scintillator, and in the closed configuration, the shutter essentially blocks the X-ray beam, preventing it from irradiating the scintillator; and

[0039] When the shutter is in the closed configuration, the stability of the pulsed X-ray beam is monitored based on the voltage of the electrical output signal from the photoelectric device.

[0040] Optoelectronic devices can be, for example, silicon photomultiplier tubes (SiPMs).

[0041] The apparatus and methods of the third and fourth aspects may be similar to those of the first and second aspects, and may include one or more features of the apparatus and methods of the first and second aspects, respectively, except that the PMT is replaced by an optoelectronic device such as a SiPM, and that no specific features related to the control of gain are necessarily present.

[0042] According to a fifth aspect, this disclosure provides an apparatus for analyzing ores, comprising:

[0043] A pulsed X-ray source configured to irradiate ore material with a pulsed X-ray beam;

[0044] A beam monitoring device comprising a scintillator that emits light when excited by an X-ray beam and a photomultiplier tube (PMT) that absorbs the light emitted by the scintillator and converts the absorbed light into an electrical output signal; and

[0045] A gain control device configured to control the gain of the PMT to a first gain during each pulse of the pulsed X-ray beam and a second gain between pulses of the X-ray beam, the second gain being higher than the first gain.

[0046] The gain control device can be configured to control the gain of the PMT synchronously or cyclically with the pulses of the X-ray beam.

[0047] The device may include a processor configured to monitor the stability of the pulsed X-ray beam based on measurements of the voltage of the electrical output signal from the PMT. Measurements may be performed during each pulse of the X-ray beam and between pulses.

[0048] Pulsed X-ray sources may include linear accelerators (LINACs). The frequency of a pulsed X-ray source may be approximately or less than 500 Hz or 300 Hz.

[0049] The difference between the first gain and the second gain can be at least 1,000 times or at least 10,000 times. In some embodiments, the first gain, which is lower than the second gain, can be a non-zero gain or a zero gain. The gain control device can control the voltage of the electrical signal supplied to the PMT and / or control the switching of the PMT's multiplier poles. The gain control device may include, for example, a switching voltage divider circuit, which can provide, for example, a switching voltage divider base for the PMT.

[0050] In some embodiments, the device may include a shield between the X-ray source and the scintillator, wherein the shield reduces the intensity of the pulsed X-ray beam irradiating the scintillator. The shield may contain bismuth.

[0051] The scintillator of a beam monitoring device may contain bromine.

[0052] The device may include at least one detector to monitor emitted radiation from the ore material in response to irradiation of the ore material by a pulsed X-ray beam.

[0053] The processor can be configured to determine a correction factor based on a measurement of the voltage of the electrical output signal from the PMT, and to correct the signal from the detector based on that correction factor. The detector may include, for example, a lanthanum bromide scintillator. The electrical output signal from the PMT may vary over time based on one or more parameters of the pulsed X-ray beam irradiating the scintillator of the beam monitoring device, such as energy, intensity, frequency, duty cycle, and / or angular distribution. Variations in any one or more of these parameters, and potentially others, can alter the amount of energy absorbed by the scintillator, and the determined correction factor can therefore account for variations in one or more of these parameters. Since the parameters of the pulsed X-ray beam can vary over time, and therefore may differ when the X-ray beam irradiates different blocks or sections of ore material, different correction factors can be determined and used to correct the signal from the detector corresponding to the emitted radiation from different blocks or sections of ore material.

[0054] The apparatus may include at least one conveyor belt on which a mineral material irradiated by a pulsed X-ray beam is located. The mineral material may move along the at least one conveyor belt between an irradiation area and a detection area, in which the mineral material is irradiated by the pulsed X-ray beam, and in the detection area, the emitted radiation from the mineral material in response to the irradiation is monitored.

[0055] According to a sixth aspect of this disclosure, a method for analyzing ore is provided, comprising:

[0056] Irradiate the mineral material with a pulsed X-ray beam from a pulsed X-ray source;

[0057] Provides a beam monitoring device comprising a scintillator that emits light when excited by an X-ray beam and a photomultiplier tube (PMT) that absorbs the light emitted by the scintillator and converts the absorbed light into an electrical output signal; and

[0058] The gain of the PMT is controlled to be a first gain during each pulse of the pulsed X-ray beam and a second gain between pulses of the X-ray beam, the second gain being higher than the first gain.

[0059] This method may include controlling the gain of the PMT in sync or cyclically with the pulses of the X-ray beam.

[0060] This method may include monitoring the stability of the pulsed X-ray beam based on measurements of the voltage of the electrical output signal from the PMT. Measurements may be performed during each pulse of the X-ray beam and between pulses.

[0061] The method of the sixth aspect may utilize the device according to the fifth aspect and / or may perform the steps described with respect to one or more features of the device according to the fifth aspect.

[0062] According to the seventh aspect, this disclosure provides an apparatus for analyzing ore, comprising:

[0063] A pulsed X-ray source configured to irradiate a mineral material with a pulsed X-ray beam; and

[0064] A beam monitoring device comprising a scintillator that emits light when excited by an X-ray beam and a photomultiplier tube (PMT) that absorbs the light emitted by the scintillator and converts the absorbed light into an electrical output signal.

[0065] A processor configured to monitor the stability of a pulsed X-ray beam based on a measurement of the voltage of the electrical output signal from the PMT during each pulse of the X-ray beam.

[0066] According to the eighth aspect, this disclosure provides a method for analyzing ore, comprising:

[0067] Irradiate the mineral material with a pulsed X-ray beam from a pulsed X-ray source;

[0068] Provides a beam monitoring device comprising a scintillator that emits light when excited by an X-ray beam and a photomultiplier tube (PMT) that absorbs the light emitted by the scintillator and converts the absorbed light into an electrical output signal; and

[0069] The stability of the pulsed X-ray beam is monitored by measuring the voltage of the electrical output signal from the PMT during each pulse of the X-ray beam.

[0070] The apparatus and methods of the seventh and eighth aspects may be similar to those of the fifth and sixth aspects, and may include one or more features of the apparatus and methods of the fifth and sixth aspects, respectively, except that the monitoring of stability may be based solely on measurements during each pulse of the X-ray beam, and in connection with this, the apparatus and methods may not necessarily have specific features related to the control of the gain of the PMT.

[0071] According to the ninth aspect, this disclosure provides an apparatus for analyzing ore, comprising:

[0072] An X-ray source configured to irradiate a mineral material with a pulsed X-ray beam; and

[0073] A detector configured to monitor emitted radiation from an ore material in response to irradiation by an X-ray source, wherein the detector includes a lanthanum bromide scintillator.

[0074] According to a tenth aspect, this disclosure provides an apparatus for analyzing ore, comprising:

[0075] An X-ray source configured to irradiate a mineral material with a pulsed X-ray beam; and

[0076] A detector configured to monitor emitted radiation from a mineral material in response to irradiation by an X-ray source.

[0077] The X-ray source is a cyclotron.

[0078] Throughout this specification, the word “comprise” or variations such as “comprises” or “comprising” will be understood to imply inclusion of the stated elements, integers or steps, or groups of elements, groups of integers or groups of steps, but does not exclude any other elements, integers or steps, or groups of elements, groups of integers or groups of steps. Attached Figure Description

[0079] Embodiments of this disclosure will now be described by way of example only, with reference to the accompanying drawings, in which:

[0080] Figure 1a and Figure 1b A schematic diagram of an apparatus for analyzing ore according to an embodiment of the present disclosure is shown;

[0081] Figure 2 A flowchart illustrating the steps of a method for analyzing ore according to an embodiment of the present disclosure is shown;

[0082] Figure 3 A schematic diagram of the operation of the scintillator and PMT is shown;

[0083] Figure 4 A timeline of the activities of components of the device according to an embodiment of the present disclosure is shown;

[0084] Figure 5a and Figure 5b A schematic diagram of an apparatus for analyzing ore according to an embodiment of the present disclosure is shown, the apparatus including a linearly actuated shutter;

[0085] Figure 6a and Figure 6bA schematic diagram of an apparatus for analyzing ore according to an embodiment of the present disclosure is shown, the apparatus including a rotatably actuated shutter;

[0086] Figure 7a and Figure 7b A schematic diagram of an apparatus for analyzing ore according to an embodiment of the present disclosure is shown, the apparatus including an electro-optically actuated shutter;

[0087] Figure 8 A schematic diagram of an apparatus for analyzing ore according to an embodiment of the present disclosure is shown;

[0088] Figure 9 A flowchart illustrating the steps of a method for analyzing ore according to an embodiment of the present disclosure is shown;

[0089] Figure 10 A timeline of the activities of components of the device according to an embodiment of the present disclosure is shown;

[0090] Figure 11 A schematic diagram of an apparatus for analyzing ore according to an embodiment of the present disclosure is shown;

[0091] Figure 12a and Figure 12b The PMT and associated gain control device according to embodiments of the present disclosure are shown in low gain mode and high gain mode, respectively.

[0092] Figure 13 A block diagram of an apparatus according to an embodiment of the present disclosure is shown;

[0093] Figure 14a and Figure 14b A schematic diagram of an apparatus for analyzing ore according to an embodiment of the present disclosure is shown;

[0094] Figure 15 A flowchart illustrating the steps of a method for analyzing ore according to an embodiment of the present disclosure is shown;

[0095] Figure 16 A graph is shown indicating the activity of isomers in a scintillator when exposed to a series of single X-ray pulses, where the pulse period is much shorter than the half-life of the isomers in the scintillator.

[0096] Figure 17 A graph showing the activation of Br-79m in a cerium bromide scintillator according to a first example of this disclosure is shown;

[0097] Figure 18 Another graph showing the activation of Br-79m in a cerium bromide scintillator according to a first example of this disclosure is shown;

[0098] Figure 19A graph showing the activation of Br-79m in a cerium bromide scintillator according to a second example of this disclosure is shown; and

[0099] Figure 20 Another graph showing the activation of Br-79m in a cerium bromide scintillator according to a second embodiment of the present disclosure is shown. Detailed Implementation

[0100] According to the embodiments of this disclosure, the apparatus 100 for ore analysis is in Figure 1a and Figure 1b The device 100 is shown and includes an X-ray source 110 configured to emit a pulsed X-ray beam 111 for irradiating a mineral material 120. The device 100 also includes a beam monitoring device 130 comprising a scintillator 131 and a photomultiplier tube (PMT) 132. The scintillator 131 is configured to emit light when excited by the X-ray beam 111, and the PMT 132 is configured to absorb the light emitted by the scintillator 131 and convert the absorbed light into an electrical output signal 150.

[0101] Device 100 also includes shutter 140, which can, for example Figure 1a The opening configuration shown is as follows Figure 1b The shutter 140 is selectively adjusted between the closed and open configurations. When the shutter 140 is in the open position, the X-ray beam 111 irradiates the scintillator 131, and when the shutter 140 is in the closed configuration, the shutter 140 substantially shields the X-ray beam 111, preventing it from irradiating the scintillator 131.

[0102] The device 100 also includes a gain control device 133 configured to control the gain of the PMT 132, and specifically, in this embodiment, the gain is controlled to a first gain when the shutter 140 is in an open configuration and a second gain when the shutter 140 is in a closed configuration, the second gain being higher than the first gain. For example, the second gain may be at least 10 times the first gain. 3 Or at least 10 4 The first gain can be a multiple of zero. In some implementations, the first gain can be a non-zero gain or a zero gain.

[0103] In some embodiments, the gain control device 133 may be part of the beam monitoring device 130, or in alternative embodiments, separate from the beam monitoring device 130. For example, the gain control device 133 may form part of a control system that optionally also controls the adjustment of the shutter 140 between an open and closed configuration. In some embodiments, the gain control device 133 may include a switching voltage divider. In some embodiments, the gain control device 133 may provide a switching voltage divider base for the beam monitoring device 130. Reference is made below. Figure 12a, Figure 12b and Figure 13 Further discussion is given of embodiments of the PMT and associated gain control device that can be used with this embodiment and other embodiments of the present disclosure, but other configurations of the PMT and gain control device may also be used.

[0104] In some embodiments, the device may include a processor configured to monitor (e.g., determine or measure) the stability of the pulsed X-ray beam 111 based on an electrical output signal 150 from the PMT 132 (e.g., a measured voltage of the electrical output signal 150), particularly when the shutter 140 is in a closed configuration and the gain of the PMT 132 is a second gain. For example, monitoring the stability of the pulsed X-ray beam 111 may include monitoring changes caused by variations in the energy and / or intensity of the pulsed X-ray beam 111 and / or other parameters of the pulsed X-ray beam 111, such as frequency, duty cycle, and / or angular distribution. Changes in any one or more of these parameters, and potentially other parameters, can alter the amount of energy absorbed by the scintillator 131, and thus the amplitude of the electrical output signal from the PMT 132. In some embodiments, the processor may be part of the beam monitoring device 130, or in alternative embodiments, it may be separate from the beam monitoring device 130.

[0105] pass Figure 2 The flowchart illustrates a method 200 according to one embodiment of the present disclosure, which can be used Figure 1a and Figure 1b The method is performed by device 100 or otherwise.

[0106] At position 210, the ore material was irradiated with a pulsed X-ray beam from a pulsed X-ray source.

[0107] At 220, the shutter is selectively adjusted between an open configuration and a closed configuration, wherein in the open position, the X-ray beam irradiates the scintillator, and in the closed configuration, the shutter essentially shields the X-ray beam, preventing it from irradiating the scintillator. The scintillator and photomultiplier tube (PMT) can form part of a beam monitoring device, wherein the scintillator emits light when excited by the X-ray beam, and the photomultiplier tube (PMT) absorbs the light emitted by the scintillator and converts the absorbed light into an electrical output signal.

[0108] At 230, the gain of the PMT is controlled as a first gain when the shutter is in the open configuration and a second gain when the shutter is in the closed configuration, with the second gain being higher than the first gain.

[0109] In some implementations, the method may further include monitoring the stability of the pulsed X-ray beam based on an electrical output signal from the PMT (e.g., a measured voltage of the electrical output signal) when the shutter is in a closed configuration and the PMT gain is a second gain. For example, monitoring the stability of the pulsed X-ray beam may include monitoring changes caused by variations in the energy and / or intensity of the pulsed X-ray beam and / or other parameters of the pulsed X-ray beam, such as frequency, duty cycle, and / or angular distribution. Changes in any one or more of these parameters, and potentially other parameters, can alter the amount of energy absorbed by the scintillator, and thus change the amplitude of the electrical output signal from the PMT.

[0110] This apparatus and method can be applied to ultrafast pulsed X-ray sources, such as cyclotrons, which would otherwise potentially damage components of a beam monitoring device and / or cause the beam monitoring device to be saturated with the high energy associated with such X-ray sources. For example, this apparatus and method can be applied to pulsed X-ray sources having a pulse frequency of at least 300 Hz or at least 500 Hz. For example, X-ray sources (such as cyclotrons) can have pulse frequencies exceeding 1 MHz, 10 MHz, or 100 MHz.

[0111] For general understanding, please refer to the following: Figure 3 The device 300 describes the function of the scintillator and associated PMT, but it should be understood that the features and advantages of this disclosure are not necessarily limited to the following theory, and various types of scintillators and PMTs can be used in the embodiments of this disclosure.

[0112] The scintillator 310 comprises a material that emits light 302 (typically photons in the visible spectrum) via a photoluminescence process when it interacts with radiation (such as X-ray photons 301 or gamma rays) irradiating the material. The PMT 320 includes a photocathode 321 located on the front surface of, for example, a vacuum tube 322. The photocathode 321 has a layer of photosensitive material, such as cesium or an alkali metal. When a photon 302 emitted by the scintillator 310 strikes the photocathode 321, the photocathode emits an electron 303 due to the photoelectric effect.

[0113] Electrons 303 emitted from photocathode 321 are accelerated within vacuum tube 322 by an electric field provided by high-voltage power supply 330 and directed toward a series of dynodes 323. Dynodes 323 are electrodes typically maintained by high-voltage power supply 330 at a gradually increasing potential (or, in some variations of the PMT, a gradually increasing potential). When electrons strike dynodes 323, the dynodes 323 release additional electrons through a process called secondary emission, and the cascaded electron emission effect between successive dynodes 323 results in a significant amplification of the original electrical signal.

[0114] At the opposite end of the vacuum tube 322 and the photocathode 321, the PMT 320 includes an anode 324 that generates an electrical output signal based on electrons collected at the last dynode 323 in the series of dynodes. The electrical output signal, which can be further amplified and processed by signal processing circuitry, can provide a measurable voltage signal proportional to parameters such as the intensity of radiation incident on the scintillator 310.

[0115] According to this disclosure, a scintillator and a pulse-mask (PMT) form a beam monitoring device that can be used to monitor the stability of a pulse beam from an X-ray source based on an electrical output signal from the PMT. See below for reference. Figure 11 Further described, this monitoring can be used, for example, to determine a correction factor to correct for measurements of isomer decay in the ore caused by X-ray source irradiation. These corrected measurements can be used as part of an ore analysis process, such as for ore sorting or other purposes. Isomer activity depends on factors such as the intensity and energy of the X-ray beam irradiating the ore; therefore, correction based on the electrical output signal of the beam monitoring device can provide more accurate ore analysis and more efficient ore sorting. The correction can take into account the stability of the X-ray beam over time when irradiating different ore materials (e.g., variations in energy and / or intensity, as well as variations in other parameters such as frequency, duty cycle, and / or angular distribution).

[0116] According to one or more embodiments of this disclosure, in Figure 4 The timeline in the image shows the adjustment of the shutter speed and control of the PMT gain over time, as well as timelines indicating the radiation activity of the scintillator and the pulse state of the pulsed X-ray source. The pulsed X-ray source in this example is a high-energy, ultrafast X-ray source, specifically a cyclotron, and the scintillator material in this example includes bromine. The scintillator is specifically a cerium bromide (CeBr) scintillator, but other bromine-containing or non-bromine-containing scintillators can also be used.

[0117] When exposed to a pulsed X-ray beam from an X-ray source, the scintillator emits high-intensity light that can damage the PMT and / or cause nonlinear electrical output signals from the PMT. In embodiments according to this disclosure, the shutter is adjusted between an open and closed configuration. When the shutter is open and the X-ray source irradiates the scintillator, the gain of the PMT decreases to a first (low) gain, thereby protecting the PMT from potential damage due to high-intensity light emission from the scintillator during continuous X-ray pulses. However, when the shutter is closed, the scintillator is shielded from the pulsed X-ray beam and therefore not strongly irradiated or activated. When the shutter is closed, the gain of the PMT increases to a second (high) gain, allowing for more accurate measurement of the scintillator's sustained but low-intensity activity (e.g., gamma-ray-excited isomer decay activity within the scintillator material, such as bromine decay activity) via the PMT and associated circuitry. This method can provide semi-continuous monitoring of X-ray beam / X-ray source stability.

[0118] The duration for which the shutter remains in each open and closed state can be significantly longer than the duration of each X-ray pulse from the X-ray source. The shutter can be maintained for, for example, 1 to 30 seconds, 5 to 25 seconds, or 10 to 20 seconds in each open and closed state, corresponding to a shutter adjustment frequency of approximately 0.03 to 1 Hz, while the X-ray source can have a frequency of approximately 500 Hz to 200 MHz. Therefore, the shutter adjustment frequency can be significantly lower than the frequency of the X-ray source (e.g., at most 1 / 10 of the latter). 3 or 1 / 10 4 or 1 / 10 5 or 1 / 10 6 or 1 / 10 7 ).

[0119] The duration for which the shutter is held in each open state can be the same as the duration for which it is held in each closed state. Alternatively, the shutter can be held in each open state for a longer time than in each closed state, or vice versa. These durations can be selected or controlled based on the desired level of X-ray beam exposure of the scintillator and the desired duration for monitoring or measuring the decay activity of the corresponding isomer.

[0120] Although Figure 4 In the implementation scheme, the change in PMT gain is synchronized with the opening and closing of the shutter. However, it should be recognized that in alternative implementation schemes, these changes may cycle with the opening and closing of the shutter, but not necessarily be synchronized with it. For example, the gain may be adjusted at the same frequency or period as the opening and closing of the shutter, but different events may or may not occur exactly simultaneously.

[0121] When the X-ray beam strikes the scintillator immediately after the shutter is set to open, the light emission from the scintillator may still be relatively low and may not have increased to a level that could damage the PMT. Therefore, the PMT gain may be maintained at a high or higher level during the initial portion of the shutter-open period, and then adjusted to a low or lower level during the remaining later portion of the shutter-open period. The initial portion of the shutter-open period may be the first 33% or less, 25% or less, 20% or less, 15% or less, or 10% or less, or may fall within these ranges.

[0122] Additionally or alternatively, when the X-ray beam is immediately shielded from irradiating the scintillator after the shutter is adjusted to the closed configuration, the light emission from the scintillator may still be relatively high and may not have decreased to a level suitable for accurate measurement of activity by the PMT. Therefore, the gain of the PMT may be maintained at a low or lower state during the initial portion of the shutter-closed period and then adjusted to a high or higher state during the later portion of the shutter-open period. The initial portion of the shutter-closed period may be the first 33% or less, 25% or less, 20% or less, 15% or less, or 10% or less of that period.

[0123] In embodiments of this disclosure, the shutter speed can be adjusted between an open configuration and a closed configuration by moving the shutter. For example, as Figure 5a and Figure 5b As shown, shutter 141 can be connected to an actuator such as linear actuator 142, which moves the shutter between a closed position and an open position. Figure 5a In the closed position shown, shutter 141 can be directly positioned between X-ray source 110 and scintillator 132, thereby shielding the scintillator from direct irradiation by X-ray source 110. Figure 5b In the open position shown, the shutter is no longer directly positioned between the X-ray source 110 and the scintillator 132, thus allowing the X-ray source 110 to directly irradiate the scintillator.

[0124] Alternatively, as Figure 5a and Figure 5b As shown, the device 100 may include a shield 143 between the X-ray source 110 and the scintillator 132. The shield 143 can be considered as a primary shield in conjunction with the secondary shield provided by the shutter 141. Even when the shutter 141 is in an open configuration, the shield 143 can reduce the intensity of the pulsed X-ray beam irradiating the scintillator.

[0125] For example, such as Figure 6a and Figure 6bAs shown, shutter 144 can be connected to an actuator such as a rotator device 145, which moves shutter 144 between an open configuration and a closed configuration, and more specifically, rotates shutter 144. Shutter 144 may include, for example, a planar element, which can be positioned as... Figure 6a The shutdown configuration shown is similar to... Figure 6b The diagram shows a rotation between open and closed configurations. In the closed configuration, the plane is substantially perpendicular to the X-ray beam and shields the X-ray beam. In the open configuration, the plane is substantially parallel to the X-ray beam and does not shield the X-ray beam.

[0126] For example, such as Figure 7a and Figure 7b As shown, the shutter can be an electro-optic shutter 146, which may remain stationary when adjusted between an open and closed configuration. The electro-optic shutter 146 can be connected to an actuator such as an electro-optic controller 147, which sends one or more electrical signals to change the polarization characteristics of the electro-optic shutter material (e.g., a liquid crystal material). Figure 7a In the closed configuration shown, the polarization characteristics of the electro-optic shutter material can be controlled, thus shielding the transmission of radiation from the X-ray source, and as... Figure 7b In the open configuration shown, the polarization characteristics of the electro-optic shutter material can be controlled, so that the transmission of radiation from the X-ray source is no longer shielded.

[0127] Although not shown, but Figure 6a and Figure 6b as well as Figure 7a and Figure 7b The equipment can also adopt the same as the one mentioned above. Figure 5a and Figure 5b The main shielding components discussed are similar to or the same as the main shielding components 143.

[0128] In some implementations, including when the shutter is as described above... Figures 5a to 6b In the case of the mechanical shutter of the type discussed, the shutter may contain bismuth. Additionally or alternatively, the main shield may contain bismuth (e.g., a combination of bismuth and lead).

[0129] While various shielding materials, including lead or layered steel, can be used in the shutter and primary shielding, bismuth has reduced activation properties compared to lead. This reduces the likelihood that the shutter might contribute to scintillating the scintillator, potentially leading to a lower signal-to-noise ratio in the electrical output of the beam monitoring device. Specifically, bismuth has only one naturally occurring isotope and may not have the associated primary activation reaction within the energy range of an X-ray source (e.g., 8–9 MeV) used to irradiate ore materials to identify the concentration of a target element (e.g., gold concentration), for example, via gamma-ray spectroscopy.

[0130] In the implementation discussed above, the PMT gain is adjusted from a first (relatively low) gain when the shutter is open (to protect the PMT) to a second (relatively high) gain when the shutter is closed, to allow for easier measurement of sustained isomer activity at the scintillator during this period. However, in alternative implementations, different optoelectronic devices (such as silicon photomultiplier tubes (SiPMs)) can be used instead of the PMT, which may not suffer the same risk of damage when exposed to high-intensity scintillation light when the shutter is open. In these alternative implementations, gain control may not be provided, or at least the gain of the optoelectronic device may not be adjusted.

[0131] Therefore, in this disclosure as Figure 14a and Figure 14b In the illustrated embodiment, the apparatus 900 for ore analysis includes an X-ray source 910 configured to emit a pulsed X-ray beam 911 for irradiating ore material 920. The apparatus 900 also includes a beam monitoring device 930 comprising a scintillator 931 and a SiPM 932. The scintillator 931 is configured to emit light when excited by the X-ray beam 911, and the SiPM 932 is configured to absorb the light emitted by the scintillator 931 and convert the absorbed light into an electrical output signal 950.

[0132] Device 900 also includes shutter 940, which can, for example Figure 14a The opening configuration shown is as follows Figure 14b The shutter 940 is selectively adjusted between the closed and open configurations. When the shutter 940 is in the open position, the X-ray beam 911 irradiates the scintillator 931, and when the shutter 940 is in the closed configuration, the shutter 940 substantially shields the X-ray beam 911, preventing it from irradiating the scintillator 931.

[0133] In some embodiments, the device may include a processor configured to monitor (e.g., determine or measure) the stability of the pulsed X-ray beam 911 based on an electrical output signal 950 from the SiPM932 (e.g., a measured voltage of the electrical output signal 950), particularly when the shutter 940 is in a closed configuration. For example, monitoring the stability of the pulsed X-ray beam 911 may include monitoring changes caused by variations in the energy and / or intensity of the pulsed X-ray beam 911 and / or other parameters of the pulsed X-ray beam 911, such as frequency, duty cycle, and / or angular distribution. Changes in any one or more of these parameters, and potentially other parameters, can alter the amount of energy absorbed by the scintillator 931, and thus change the amplitude of the electrical output signal 950 from the SiPM932. In some embodiments, the processor may be part of the beam monitoring device 930, or in alternative embodiments, it may be separate from the beam monitoring device 930.

[0134] Device 900 may have any of the same features and functions as the device discussed above with respect to the foregoing embodiments, but may not necessarily have gain control features or functions. SiPM 932 may be replaced by alternative types of optoelectronic devices, which may also have a reduced risk of damage compared to PMT due to exposure to high-intensity flicker light.

[0135] pass Figure 15 The flowchart illustrates a method 1000 according to one embodiment of the present disclosure, which can be used Figure 14a and Figure 14b The method is performed by device 900 or otherwise.

[0136] At position 1010, the ore material is irradiated with a pulsed X-ray beam from a pulsed X-ray source.

[0137] At 1020, the shutter is selectively adjusted between an open configuration and a closed configuration, wherein in the open position, the X-ray beam irradiates the scintillator, and in the closed configuration, the shutter substantially shields the X-ray beam, preventing it from irradiating the scintillator. The scintillator and the SiPM can form part of a beam monitoring device, wherein the scintillator emits light when excited by the X-ray beam, and the SiPM absorbs the light emitted by the scintillator and converts the absorbed light into an electrical output signal.

[0138] In this disclosure, terms such as “shielded” or “blocked” and “closed” are generally used to describe the function of the shutter in preventing X-ray beams from directly irradiating the scintillator. However, it should be understood that these terms do not necessarily mean that no radiation from the X-ray source is incident on the scintillator when the beam is “shielded” or the shutter is “closed.” For example, some indirect X-ray radiation may still reach the scintillator, and / or a reduced portion of the X-ray beam may still directly irradiate the scintillator. However, it should be understood that when the shutter is in a closed configuration and the X-ray beam is substantially shielded, the intensity of the X-ray radiation incident on the scintillator is significantly reduced compared to when the shutter is in an open configuration and the X-ray beam is unshielded. For example, in the closed / shielded state, the intensity may be reduced by at least 50%, at least 75%, at least 80%, at least 90%, or at least 95% compared to the open / unshielded state.

[0139] According to another embodiment of this disclosure, an apparatus 400 for analyzing ore 420 is provided. Figure 8The device 400 is shown and includes an X-ray source 410 configured to emit a pulsed X-ray beam 411 for irradiating a mineral material 420. The device 400 also includes a beam monitoring device 430 comprising a scintillator 431 and a photomultiplier tube (PMT) 432. The scintillator 431 is configured to emit light when excited by the X-ray beam 411, and the PMT 432 is configured to absorb the light emitted by the scintillator 431 and convert the absorbed light into an electrical output signal 450.

[0140] The device 400 also includes a gain control device 433 configured to control the gain of the PMT 432 to a first gain during each pulse of the pulsed X-ray beam 411 and a second gain between pulses of the X-ray beam (e.g., between each pulse), the second gain being higher than the first gain. In some embodiments, the gain control device 433 may include a switched voltage divider. The gain control device 433 may provide a switched voltage divider base for the beam monitoring device 430. Reference is made below. Figure 12a , Figure 12b and Figure 13 Further discussion is given of embodiments of the PMT and associated gain control device that can be used with this embodiment and other embodiments of the present disclosure, but other configurations of the PMT and gain control device may also be used.

[0141] The device 400 may also include a processor configured to monitor the stability of the pulsed X-ray beam 411 based on an electrical output signal 450 from the PMT 432 (e.g., a measured voltage of the electrical output signal 450). For example, monitoring the stability of the pulsed X-ray beam 411 may include monitoring changes caused by variations in the energy and / or intensity of the pulsed X-ray beam 411 and / or other parameters of the pulsed X-ray beam 411, such as frequency, duty cycle, and / or angular distribution. Changes in any one or more of these parameters, and potentially other parameters, can alter the amount of energy absorbed by the scintillator 431, and thus change the amplitude of the electrical output signal 450 from the PMT 432.

[0142] In some embodiments, the gain control device 433 may be part of the beam monitoring device 430, or in alternative embodiments it may be separate from the beam monitoring device 430. Similarly, in some embodiments, the processor may be part of the beam monitoring device 430, or in alternative embodiments it may be separate from the beam monitoring device 430.

[0143] pass Figure 9 The flowchart illustrates a method 500 according to one embodiment of the present disclosure, which can be used... Figure 8 The method is performed by device 400 or otherwise.

[0144] At position 510, the ore material was irradiated with a pulsed X-ray beam from a pulsed X-ray source.

[0145] At 520, the gain of the PMT is controlled to be a first gain during each pulse of the pulsed X-ray beam and a second gain between pulses of the X-ray beam (e.g., between each pulse), the second gain being higher than the first gain. A photomultiplier tube (PMT) and a scintillator can form part of a beam monitoring device, wherein the scintillator emits light when excited by the X-ray beam, and the photomultiplier tube (PMT) absorbs the light emitted by the scintillator and converts the absorbed light into an electrical output signal.

[0146] This method may include monitoring the stability of the pulsed X-ray beam based on an electrical output signal from the PMT (e.g., a measured voltage of the electrical output signal). For example, monitoring the stability of the pulsed X-ray beam may include monitoring changes caused by variations in the energy and / or intensity of the pulsed X-ray beam and / or other parameters of the pulsed X-ray beam, such as frequency, duty cycle, and / or angular distribution. Changes in any one or more of these parameters, and potentially other parameters, can alter the amount of energy absorbed by the scintillator, and thus change the amplitude of the electrical output signal from the PMT.

[0147] refer to Figure 8 and Figure 9 The described equipment and methods can be applied to devices that are compatible with those referenced above, for example... Figure 1a and Figure 1b The described apparatus is used with a slower pulsed X-ray source. For example, the apparatus and method can be adapted to pulsed X-ray sources with pulse frequencies of about or less than 500 Hz or 300 Hz. For example, the X-ray source can be a linear particle accelerator (LINAC) instead of a cyclotron accelerator.

[0148] The radiation energy of X-ray sources such as LINACs can also cause damage to components of beam monitoring devices such as PMTs and / or result in nonlinear electrical signal outputs from the beam monitoring device. However, LINACs typically have much lower pulse rates than cyclotrons. Based on this, this disclosure has determined that gain control synchronized or cyclically with the periodic “on” and “off” states of the pulsed X-ray beam from a LINAC or other lower-energy X-ray source can be sufficient to avoid PMT damage and / or nonlinear or saturation effects. Switching the PMT gain sufficiently fast in synchronization with the “on” and “off” states of the pulsed X-ray beam may be feasible for lower-frequency sources such as LINACs, but may not be feasible for higher-frequency sources such as cyclotrons.

[0149] Similarly, beam monitoring according to the apparatus and method of this embodiment can be used, for example, to determine correction factors for correcting measurements of isomer decay in ore caused by X-ray source irradiation. These corrected measurements can be used as part of an ore analysis process, such as for ore sorting or other purposes. As mentioned above, isomer activity depends on parameters such as the energy and / or intensity of the X-ray beam irradiating the ore; therefore, correction based on the electrical output signal from the PMT of the beam monitoring device can provide more accurate ore analysis and more efficient ore sorting. The correction can take into account the stability of the X-ray beam over time when irradiating different ore materials (e.g., changes in energy and / or intensity, or changes in other parameters such as frequency, duty cycle, and / or angular distribution). Since the parameters of the pulsed X-ray beam can vary over time, and therefore may differ when the X-ray beam irradiates different blocks or sections of ore material, different correction factors can be determined and used to correct the signal from the detector corresponding to the emitted radiation from different blocks or sections of ore material.

[0150] According to one or more embodiments of this disclosure, in Figure 10 The timeline shown illustrates the control of the PMT gain over time, as well as timelines indicating the radioactivity of the scintillator and associated fluorescence output, and the pulse state of the pulsed X-ray source. The pulsed X-ray source in this example is a LINAC, and the scintillator material in this example includes bromine. Specifically, the scintillator is a cerium bromide (CeBr) scintillator, but other bromine-containing or non-bromine-containing scintillators may also be used.

[0151] Although the control of PMT gain is usually related to Figure 10 The on and off states of the pulsed X-ray beam are synchronized; however, it should be recognized that these changes can cycle with both the on and off states of the pulsed X-ray beam, but are not necessarily synchronized with both. For example, as... Figure 10 As shown, the gain can be maintained at a low gain for a longer period of time than the on state of each X-ray beam pulse, and more closely corresponds to the longer period of high fluorescence activity from the scintillator after the emission of each X-ray pulse.

[0152] When exposed to a pulsed X-ray beam from an X-ray source, the scintillator is excited by the X-ray source and provides a large fluorescence output that can damage the PMT and / or cause a nonlinear electrical output signal from the PMT. PMTs, which operate with scintillators to measure the energy deposited within their volume, are typically designed and optimized to convert and amplify the light generated by the scintillator due to the deposition of a single X-ray (or gamma-ray) of approximately 50 keV to 2 MeV. While multiple photons may interact with the scintillator for a short period, there is usually sufficient time to process each individual event before the next event occurs. However, under LINAC irradiation, the scintillator can exhibit 10... 9 - 10 15 Each X-ray photon deposits energy within its volume (depending on shielding, location, scintillator size, etc.), resulting in energies up to 9 MeV in pulses several microseconds long. The resulting fluorescence signal has no time to dissipate between each interaction, thus producing an intensity of 10... 6 - 10 10 A powerful composite fluorescent pulse, when amplified by a PMT, can cause serious damage to the PMT and other processing electronics.

[0153] However, as from Figure 10 As is evident in the timeline, in embodiments according to this disclosure, the gain of the PMT is controlled to a lower gain during each pulse of the pulsed X-ray beam (“on” state), thereby protecting the PMT during each fluorescence output peak and generally converting the output from the scintillator into a more measurable range. Furthermore, the gain of the PMT is controlled to a higher gain between each pulse of the X-ray beam (“off” state) and therefore between each fluorescence output peak, thereby providing a higher electrical output signal from the PMT and thus enabling more accurate monitoring of beam stability based on the sustained isomer activity (bromine activity in this example) between each pulse. This method allows beam monitoring devices to continuously or substantially continuously monitor the stability of an X-ray beam from an X-ray source. Monitoring based on the fluorescence activity when the X-ray beam pulse irradiates the scintillator and the isomer activity within the scintillator material between the X-ray pulses irradiating the scintillator can identify a more specific energy distribution of the X-ray beam. For example, combined monitoring of these different activities can determine more accurate or detailed information about X-ray beam stability compared to monitoring one of these activities individually.

[0154] More specifically, measuring the activity of isomers (e.g., bromine) between pulses of an X-ray beam from an X-ray source such as LINAC can have some limitations. For example, LINAC operating at 500 Hz has pulses arriving at the scintillator every 2 milliseconds. For instance, since the half-life of bromine-79m is 4.85 seconds, only a small fraction of the activated nuclei decay and disappear within each 2-millisecond cycle, and the activity of the isomer accumulates gradually over multiple pulses. This eventually leads to reaching the maximum bromine activity range (saturation), because the number of activated nuclei decaying with each pulse equals the amount added. The saturation point depends on the activation rate (the product of the dose rate and the reaction cross-section) and the half-life (which is constant). Within the 2-millisecond window between pulses where the decay of activated nuclei can be measured, only about 0.03% of these isomers decay and produce measurable results. Figure 16 The graph provides an example of this active buildup across individual X-ray pulses (the axes are arbitrary for illustration). Even fast scintillators can only handle a limited number of radiation events within such a short window. Considering that bromine is just one of many potential isomers activated in the process, the device may have limited ability to detect and process enough events to accurately determine the activity of the bromine isomer produced by a single X-ray beam pulse. This is still permissible, but limits the technique's ability to monitor beam stability across the entire energy spectrum of an X-ray source, at least over a small number of X-ray beam pulses.

[0155] Conversely, monitoring the fluorescence response of a scintillator when an X-ray beam pulse irradiates it can provide useful information about the general performance of the X-ray source, but it can provide more limited spectral information.

[0156] However, by combining the monitoring of isomer activity with the monitoring of fluorescence activity when the pulse is irradiated onto the scintillator, higher precision or information about the stability of the X-ray beam can be obtained, for example, to determine an appropriate correction factor based on the above discussion.

[0157] In alternative implementations, despite the aforementioned potential limitations, monitoring of X-ray beam stability can be based solely on the electrical output signal from the PMT measured during each X-ray beam pulse (i.e., based on the fluorescence activity when each X-ray beam pulse irradiates the scintillator) or solely on the electrical output signal from the PMT between each X-ray beam pulse (i.e., based on isomer decay activity). Monitoring X-ray beam stability in this manner can still provide sufficiently useful information for determining the correction factor.

[0158] Specifically, when X-ray beam stability is monitored solely based on the electrical output signal from the PMT measured during each X-ray beam pulse, the PMT gain can be maintained at a (relatively low) gain value throughout the process. This gain is chosen to prevent damage to the PMT when the X-ray beam pulse irradiates the scintillator. Since there is no monitoring based on the isomer activity within the scintillator material between X-ray beam pulses, it may not be necessary to increase the PMT gain between X-ray beam pulses.

[0159] Although different implementations have been described above, some of which employ both shutter and gain control, while others employ only gain control or none at all, the device according to the embodiments of this disclosure can be adapted to enable the use of different methods. For example, the device may be provided with a shutter and an associated shutter controller and gain controller. However, the shutter controller can be selectively placed in any of the following modes: (i) an open mode, wherein the shutter adjusts between an open configuration and a closed configuration to perform, for example... Figure 2 or Figure 15 The method, and (ii) the closed mode, wherein the shutter remains open or at least does not adjust between the open and closed configurations to perform, for example Figure 9 The method. Furthermore, the gain controller can be selectively placed in any of the following modes: (i) a first mode, wherein the gain is controlled according to the shutter adjustment to perform, for example... Figure 2 The method, and (ii) the second mode, wherein gain is controlled independently of any shutter adjustment to perform, for example Figure 9 The method, or (iii) the third mode, in which gain control is not performed at all. This allows the device to be adapted for use with different types of X-ray sources, such as cyclotrons or LINACs, and to employ different methods depending on the implementation described herein.

[0160] This disclosure recognizes that using a cyclotron as a pulsed X-ray source can have one or more advantages compared to using a LINAC. For example: (i) the cyclotron can be better shielded, thereby reducing the degree to which the detector and / or the outside world may require further shielding; (ii) the cyclotron can have higher power efficiency and / or greater stability; (iii) the cyclotron can have a higher pulse rate close to continuous irradiation, thereby potentially increasing the uniformity of ore irradiation, which can increase the accuracy of ore analysis; and / or (iv) the cyclotron can be more compact and modular.

[0161] According to the embodiments of this disclosure, the apparatus 600 for analyzing ore is in Figure 11As shown in the diagram. The device may include any one of devices 100, 400, and 900 and / or any one of methods 200, 500, and 1000 as discussed above or otherwise. Device 600 may be an ore sorting device, such as a real-time bulk ore sorting device, and may be configured to, for example, use gamma activation analysis / gamma-ray spectroscopy to detect valuable elements of interest in ore materials (such as gold). In some embodiments, the ore material may be secondary crushed ore.

[0162] The device 600 includes: an X-ray source 610 configured to emit a pulsed X-ray beam 611 for irradiating ore material 620 at an irradiation area 631; a transport system including one or more conveyor belts 630 for transporting the ore material 620 along an ore transport path from the irradiation area 631 to a detection area 632; and one or more detectors 640 for detecting radiation emitted from the ore material 620 at the detection area 632. Adjacent to the X-ray source 610 are a beam monitoring device 660 and an associated shielding element 670. The beam monitoring device 660 may include, for example, regarding... Figure 1a and Figure 1b Equipment 100, or Figure 8 Equipment 400, or Figure 14a and Figure 14b The device 900 may include one or more of the aforementioned beam monitoring features, including scintillators 131, 431, 931, PMTs 132, 432 and / or SiPM 932, shutters 140, 141, 144, 146 and / or gain control devices 133, 433. The shield 670 may be referenced above. Figure 5a and Figure 5b The shielding component 143 discussed is similar to or the same as that discussed.

[0163] The ore transport path may include a bend 633 located between the irradiation area 631 and the detection area 632. The bend 633 ensures that there is no line-of-sight path between the irradiation area 631 and the detection area 632. In this regard, the device 600 may employ one or more of the bends and / or other shielding features described in the applicant's U.S. Patent Publication No. US2021 / 0208087, the entire contents of which are incorporated herein by reference.

[0164] like Figure 11 As shown, one or more radiation shields 650 are also provided, which can surround the conveying system including one or more conveyor belts 630. The radiation shields 650 can be provided to suppress radiation leakage from the equipment 600 as the ore travels along the conveying system.

[0165] One or more detectors 640 may each include a scintillator, and optionally also include a PMT or a SiPM, and in the case of a PMT, as referenced above. Figure 3 The discussion proceeds to the operation. In one embodiment, one or more of the detectors 630 include lanthanum bromide (LaBr) scintillators. The LaBr scintillators can be installed relatively close to the activated ore and can continuously detect the radiation activity of the ore as it passes through the detection area.

[0166] Choosing a LaBr scintillator may be advantageous for one or more of the following reasons: (i) LaBr scintillators can have relatively low activation and afterglow compared to other scintillators; (ii) LaBr scintillators can be manufactured to have a relatively large volume compared to other scintillators, allowing the scintillator to detect radiation along a larger detection area / path of the conveying system; (iii) LaBr scintillators can have higher resolution than other scintillators (such as sodium iodide (NaI) scintillators), which are considered industry-standard conventional large-area scintillators and can have the minimum resolution required for detecting gold in ores; (iv) LaBr scintillators can have a faster decay time compared to NaI scintillators, allowing for increased throughput and reduced detection efficiency loss at higher count rates due to dead time; and (v) LaBr scintillators can have relatively high radiation hardness (resistance to radiation-induced damage), which allows them to be located closer to the activation point.

[0167] The device 600 can be adapted to irradiate ore 620 for gamma activation analysis. Therefore, one or more detectors 640 can be configured to detect gamma rays (gamma radiation) irradiated from the ore material 620.

[0168] In any of the embodiments disclosed herein, device 600 may be configured to batch sort ore material based on analysis of the element of interest (target element) of the ore material. In some embodiments, device 600 may include a diversion station (not shown) configured to divert the ore material after it has passed through a detection zone, the diversion being based on a measurement of radiation output detected by one or more detectors 640.

[0169] The device 600 may include a processor 680 configured to monitor output signals from one or more detectors that can indicate photon decay signals from irradiated ore 620. The processor 680 may also be configured to monitor output signals from a beam monitoring device 660. Based on electrical output signals from the beam monitoring device 660 (e.g., a measured voltage of the electrical output signal), the processor 680 may determine a correction factor to correct the output signals from one or more detectors 640. The processor 680 may be configured to determine target elements in the ore based on the corrected output signals, and optionally to control the diversion and sorting of the ore based on the corrected output signals.

[0170] The correction process described above with respect to device 600 or otherwise can rely on a known ratio of the two reaction cross sections, and particularly on the activity of isomers (e.g., bromine) in the scintillator of the beam monitoring device and the activity of a target element (e.g., gold) in the ore material detected at one or more detectors. The activity of the target element detected by one or more detectors is expected to vary due to differences in the concentration and parameters of the target element (such as the intensity and / or energy of the pulsed X-ray beam irradiating the ore material (including the target element)) (i.e., the stability or performance of the pulsed X-ray beam). On the other hand, since the number of isomers in the scintillator of the beam monitoring device is constant, any variation in the activity of isomers in the scintillator of the beam monitoring device can be attributed to variations in the stability or performance of the pulsed X-ray beam, and therefore to variations in the energy deposited by the pulsed X-ray beam in the scintillator. Therefore, ultimately, when seeking to determine the concentration of the target element, appropriate corrections can be made to eliminate variations due to X-ray beam stability. In this respect, the method can employ various principles of gamma-ray spectroscopy. The apparatus and / or methods described in this disclosure may optionally employ gamma-ray analysis techniques and principles described, for example, in PCT Publication Nos. WO2015 / 089580A1 and WO2022 / 047537A1, the entire contents of which are incorporated herein by reference.

[0171] When electrical output signals are monitored from a beam monitoring device or one or more detectors, the voltage (or more specifically, charge) of these signals is proportional to the energy deposited in the scintillator. By measuring the time integral (area under the signal curve) and / or amplitude of these voltage signals, charge estimation can be performed, thus allowing the study of the energy spectrum of the radiation impacting the scintillator.

[0172] Figure 12a and Figure 12b The document illustrates an implementation of a PMT and associated gain control architecture that can be used in the embodiments described above, including switching between higher and lower PMT gain modes.

[0173] Specifically, a PMT 700 is provided, in which the PMT includes a photocathode 701, a focusing dynode 702, a plurality of additional dynodes 703-707, an anode 708, readout electronics 709, a high-voltage source 710, and a resistor chain 711. The PMT 700 is configured to absorb scintillation light, convert the light into an electrical signal via the photoelectric effect, and is generally in accordance with the above reference. Figure 3 The principle explained is to amplify the electrical signal. The amplification in the PMT's "high gain" mode is based on the gradually corrected potential between multipliers 703-707, which are generated by their connection to the high-voltage power supply 710 and the associated resistor chain 711.

[0174] refer to Figure 12b In order to put the PMT into “low gain” mode, the first multiplier 703 is disconnected from the high voltage power supply and resistor chain 711 and connected to a separate power supply 712, thereby providing a small positive potential at the first multiplier 703, and switching the voltages of the third multiplier 705 and the fourth multiplier 706 to reduce the positive potential on the multiplier sequence again, and thus reduce the overall gain.

[0175] Although Figure 12a and Figure 12b The diagram shows an 8-dynamometer PMT (with an additional focused dynamometer), but various different PMT arrangements can be used depending on the desired gain, including with more dynamometers, such as 12 or 16 dynamometers. Furthermore, Figure 12a and Figure 12b The arrangement shown is a grounded cathode (positive high voltage) design, which can be replaced by a grounded anode (negative high voltage) design with minor modifications to the relevant electronics. However, the core dynode operation and switching method can remain essentially the same. For example, the voltage connection of one or more dynodes to an independent power supply and / or switching two or more dynodes can be used again.

[0176] Figure 13 A block diagram of an apparatus 800 according to an embodiment of the present disclosure is shown. This apparatus can be used to monitor the stability of an X-ray beam from an X-ray source and can be generally referenced as described above. Figure 12a and Figure 12bGain switching is performed as described. Device 800 includes a PMT 801 and an associated resistor chain 802 and a switching dynode architecture 803, wherein some dynodes are switched or others are not switched when changing between high and low gain. Resistor chain 802 and switching dynode architecture 803 may be connected to (or actually form part of) the voltage divider base 804 of PMT 801. High-voltage power supply 805 is connected to voltage divider base 804, and the switching between high and low gain is triggered based on a gate signal generated by pulse generator 807 according to logic signals from X-ray source 808 (e.g., LINAC or cyclotron). The electrical output signal from PMT 801 is fed via voltage divider base 804 through preamplifier 809, then undergoes analog-to-digital conversion at digitizer 810, and the resulting digital signal is then processed by processor / software 811, for example, to determine correction factors as part of ore analysis, as discussed further above. Although Figure 13 Not shown, but according to one or more of the above embodiments, the device may also include a shutter and an associated shutter controller.

[0177] The apparatus and methods according to this disclosure may employ a memory storing executable code and a processor configured to access the memory to execute the executable code, wherein when the executable code is executed, the processor may be caused to perform any one or more of the processing / method steps described herein. Additionally or alternatively, a computer-readable storage medium may provide stored instructions that, when executed by a processor, cause the processor to perform any one of the processing / method steps described herein. Example 1

[0178] Activation of Br-79m in a cerium bromide (CeBr) scintillator was tested using a 100 kW 7 MV cyclotron emitting pulsed X-ray beams and a pulsed X-ray meter (PMT). Instead of using an adjustable shutter between the cyclotron and the scintillator (moving the shutter between open and closed positions), shutter operation was simulated by turning off the cyclotron during a short period of 10–30 seconds while it was on and pulsed X-rays from the cyclotron irradiated the scintillator. The PMT gain switched between low gain during the period when the cyclotron was on and high gain after the cyclotron was off. Data acquisition / Br-79m activation monitoring from the PMT was performed when the cyclotron was off and the PMT gain was high. Figure 17 A graph of Br-79m activation is provided, and the Br-79m peak representing the full-energy deposition of the isomer at 207 keV is shown.

[0179] Activation of Br-79m was measured at three different time points (5 seconds, 10 seconds, and 30 seconds) during pulsed X-ray irradiation, yielding three distinct Br-79m peaks, such as... Figure 18 As shown. For clarity, the data is smoothed by convolution with a Gaussian function. Deviations in beam energy and intensity will produce similar (though smaller) changes at the activity level, so this method can be used to monitor beam stability (which can be more or less stable depending on the degree of fluctuation in X-ray beam parameters such as energy, intensity, etc.) and generate one or more correction factors to correct for activity measurements in ores, such as gold activation, due to the instability of the X-ray beam over time. Example 2

[0180] Activation of Br-79m in a cerium bromide (CeBr) scintillator was tested using a 10 MV linear accelerator (LINAC) emitting pulsed X-ray beams at 12.5 Hz and a pulsed magnetic resonance imaging (PMT). The PMT gain was switched between low gain during each pulse and high gain between each pulse. Data acquisition / Br-79m activation monitoring from the PMT was performed over thousands of X-ray pulses. Figure 19 A graph of Br-79m activation is provided, and the Br-79m peak representing the full-energy deposition of the isomer at 207 keV is shown.

[0181] During a 10-minute pulsed X-ray irradiation period, the activation of Br-79m was measured at three different time points (0-120 seconds, 240-360 seconds, and 480-600 seconds), yielding three distinct Br-79m peak distributions, such as... Figure 20 As shown. Deviations in beam energy and intensity will produce similar (albeit smaller) changes at the activity level, so this method can be used to monitor beam stability (which can be more or less stable depending on the degree of fluctuation in X-ray beam parameters such as energy, intensity, etc.) and generate one or more correction factors to correct for activity measurements in ores, such as gold activation, due to the instability of X-ray beam stability over time.

[0182] Those skilled in the art will understand that many variations and / or modifications can be made to the above embodiments without departing from the broad overall scope of this disclosure. For example, while embodiments of this disclosure have been described as particularly suitable for fields requiring the analysis of elements in mineral (ore) samples, these embodiments can also be applied to radiography, cargo screening, fissile material detection, and / or sterilization operations, where articles other than ore materials are irradiated by an X-ray beam, and it may be necessary to monitor the stability of the X-ray beam, providing shielding and / or detection characteristics according to the above embodiments. Therefore, these embodiments should be considered illustrative rather than limiting in all respects.

Claims

1. An apparatus for analyzing ore, comprising: A pulsed X-ray source, the pulsed X-ray source being configured to irradiate a mineral material with a pulsed X-ray beam; A beam monitoring device, comprising a scintillator that emits light when excited by the X-ray beam and a photomultiplier tube (PMT) that absorbs the light emitted by the scintillator and converts the absorbed light into an electrical output signal. A shutter that can be selectively adjusted between an open configuration and a closed configuration, wherein in the open position, the X-ray beam irradiates the scintillator, and in the closed configuration, the shutter substantially shields the X-ray beam, preventing it from irradiating the scintillator; and A gain control device configured to control the gain of the PMT to a first gain when the shutter is in the open configuration and a second gain when the shutter is in the closed configuration, wherein the second gain is higher than the first gain.

2. The device of claim 1, wherein the gain control device is configured to synchronously or cyclically control the gain of the PMT between the open configuration and the closed configuration, adjusting the shutter.

3. The device of claim 1 or 2, further comprising a processor configured to monitor the stability of the pulsed X-ray beam based on a measurement of the voltage of the electrical output signal from the PMT when the shutter is in the closed configuration and the gain of the PMT is the second gain.

4. The apparatus according to claim 1, 2 or 3, wherein the pulsed X-ray source comprises a cyclotron.

5. The device according to any one of the preceding claims, wherein the frequency of the pulsed X-ray source is greater than 300 Hz or greater than 500 Hz.

6. The device according to any one of the preceding claims, wherein the difference between the first gain and the second gain is at least 1,000 times or at least 10,000 times.

7. The device according to any one of claims 1 to 5, wherein the first gain is zero gain.

8. The device according to any one of the preceding claims, comprising an actuator configured to adjust the shutter between the open configuration and the closed configuration.

9. The device of claim 8, wherein the actuator periodically and automatically adjusts the shutter between the open configuration and the closed configuration.

10. The device according to claim 8 or 9, wherein the actuator comprises a linear actuator.

11. The device according to any one of the preceding claims, wherein the gain control device controls the voltage of the electrical signal supplied to the PMT and / or controls the switching of the multiplier pole of the PMT.

12. The device according to any one of the preceding claims, wherein the gain control device comprises a switching voltage divider circuit.

13. The device according to any one of the preceding claims, comprising a controller, wherein the controller is configured to control at least one of the following: Adjusting the shutter speed between the open configuration and the closed configuration; and The gain of the PMT is controlled between the first gain and the second gain.

14. The device according to any one of the preceding claims, wherein the shutter comprises bismuth.

15. The device according to any one of the preceding claims, comprising a shield between the X-ray source and the scintillator, wherein the shield reduces the intensity of the pulsed X-ray beam irradiating the scintillator.

16. The device of claim 15, wherein the shielding comprises bismuth.

17. The device according to any one of the preceding claims, wherein the scintillator of the beam monitoring device comprises bromine.

18. The device according to any one of the preceding claims, comprising a detector that monitors emitted radiation from the ore material in response to irradiation of the ore material by the pulsed X-ray beam.

19. The device of claim 18, when dependent on claim 3, wherein the processor is configured to determine a correction factor based on the measurement of the voltage of the electrical output signal from the PMT, and to correct the signal from the detector based on the correction factor.

20. The device of claim 19, wherein the detector comprises a lanthanum bromide scintillator.

21. The apparatus according to any one of the preceding claims, comprising at least one conveyor belt, wherein the ore material irradiated by the pulsed X-ray beam is located on the at least one conveyor belt.

22. An apparatus for analyzing ore, comprising: A pulsed X-ray source, the pulsed X-ray source being configured to irradiate a mineral material with a pulsed X-ray beam; A beam monitoring device, comprising a scintillator that emits light when excited by the X-ray beam and an optoelectronic device that absorbs the light emitted by the scintillator and converts the absorbed light into an electrical output signal; A shutter that can be selectively adjusted between an open configuration and a closed configuration, wherein in the open position, the X-ray beam irradiates the scintillator, and in the closed configuration, the shutter substantially shields the X-ray beam, preventing it from irradiating the scintillator; and A processor configured to monitor the stability of the pulsed X-ray beam based on a measurement of the voltage of the electrical output signal from the optoelectronic device when the shutter is in the closed configuration.

23. The device according to claim 22, wherein the photoelectric device is a silicon photomultiplier tube (SiPM).

24. An apparatus for analyzing ore, comprising: A pulsed X-ray source, the pulsed X-ray source being configured to irradiate a mineral material with a pulsed X-ray beam; A beam monitoring device, comprising a scintillator that emits light when excited by the X-ray beam and a photomultiplier tube (PMT) that absorbs the light emitted by the scintillator and converts the absorbed light into an electrical output signal. and A gain control device configured to control the gain of the PMT to a first gain during each pulse of the pulsed X-ray beam and a second gain between pulses of the X-ray beam, the second gain being higher than the first gain.

25. The apparatus of claim 24, wherein the gain control device is configured to control the gain of the PMT synchronously or cyclically with the pulses of the X-ray beam.

26. The device of claim 24 or 25, further comprising a processor configured to monitor the stability of the pulsed X-ray beam based on a measurement of the voltage of the electrical output signal from the PMT.

27. The apparatus according to any one of claims 24 to 26, wherein the pulsed X-ray source comprises a linear accelerator (LINAC).

28. The apparatus according to any one of claims 24 to 27, wherein the frequency of the pulsed X-ray source is about or less than 500 Hz or 300 Hz.

29. The device according to any one of claims 24 to 28, wherein the difference between the first gain and the second gain is at least 1,000 times or at least 10,000 times.

30. The device according to any one of claims 24 to 29, wherein the gain control device controls the voltage of the electrical signal supplied to the PMT and / or controls the switching of the multiplier pole of the PMT.

31. The device according to any one of claims 24 to 30, wherein the gain control device comprises a switching voltage divider circuit.

32. The apparatus according to any one of claims 24 to 31, comprising a shield between the X-ray source and the scintillator, wherein the shield reduces the intensity of the pulsed X-ray beam irradiating the scintillator.

33. The device of claim 32, wherein the shielding comprises bismuth.

34. The device according to any one of claims 24 to 33, wherein the scintillator of the beam monitoring device comprises bromine.

35. The device according to any one of claims 24 to 34, comprising a detector that monitors emitted radiation from the ore material in response to irradiation of the ore material by the pulsed X-ray beam.

36. The apparatus of claim 35, when dependent on claim 26, wherein the processor is configured to determine a correction factor based on the measurement of the voltage of the electrical output signal from the PMT, and to correct the signal from the detector based on the correction factor.

37. The device of claim 36, wherein the detector comprises a lanthanum bromide scintillator.

38. The apparatus according to any one of claims 24 to 37, comprising at least one conveyor belt, wherein the ore material irradiated by the pulsed X-ray beam is located on the at least one conveyor belt.

39. An apparatus for analyzing ore, comprising: A pulsed X-ray source, the pulsed X-ray source being configured to irradiate a mineral material with a pulsed X-ray beam; A beam monitoring device configured to monitor the stability of the pulsed X-ray beam, the beam monitoring device comprising a scintillator that emits light when excited by the X-ray beam and a photomultiplier tube (PMT) that absorbs the light emitted by the scintillator and converts the absorbed light into an electrical output signal. and A processor configured to monitor the stability of the pulsed X-ray beam based on a measurement of the voltage of the electrical output signal from the PMT during each pulse of the X-ray beam.

40. An apparatus for analyzing ore, comprising: An X-ray source configured to irradiate a mineral material with a pulsed X-ray beam; and A detector configured to monitor emitted radiation from the ore material in response to irradiation of the ore material by the X-ray source, wherein the detector comprises a lanthanum bromide scintillator.

41. An apparatus for analyzing ore, comprising: An X-ray source configured to irradiate a mineral material with a pulsed X-ray beam; and A detector configured to monitor emitted radiation from the ore material in response to irradiation of the ore material by the X-ray source. The X-ray source mentioned above is a cyclotron.

42. A method for analyzing ore, comprising: Irradiate the mineral material with a pulsed X-ray beam from a pulsed X-ray source; A beam monitoring device is provided, the beam monitoring device comprising a scintillator that emits light when excited by the X-ray beam and a photomultiplier tube (PMT) that absorbs the light emitted by the scintillator and converts the absorbed light into an electrical output signal. The shutter speed is selectively adjusted between an open configuration and a closed configuration, wherein in the open position, the X-ray beam irradiates the scintillator, and in the closed configuration, the shutter substantially shields the X-ray beam, preventing it from irradiating the scintillator; as well as The gain of the PMT is controlled to a first gain when the shutter is in the open configuration and a second gain when the shutter is in the closed configuration, wherein the second gain is higher than the first gain.

43. The method of claim 42, further comprising controlling the gain of the PMT synchronously or cyclically between the open configuration and the closed configuration by adjusting the shutter speed.

44. The method of claim 42 or 43, further comprising monitoring the stability of the pulsed X-ray beam based on a measurement of the voltage of the electrical output signal from the PMT when the shutter is in the closed configuration and the gain of the PMT is the second gain.

45. A method for analyzing ore, comprising: Irradiate the mineral material with a pulsed X-ray beam from a pulsed X-ray source; A beam monitoring device is provided, the beam monitoring device comprising a scintillator that emits light when excited by the X-ray beam and a photomultiplier tube (PMT) that absorbs the light emitted by the scintillator and converts the absorbed light into an electrical output signal. The gain of the PMT is controlled to be a first gain during each pulse of the pulsed X-ray beam and a second gain between pulses of the X-ray beam, the second gain being higher than the first gain.

46. ​​The method of claim 45, further comprising controlling the gain of the PMT in sync with or cyclically in relation to the pulses of the X-ray beam.

47. The method of claim 45 or 46, further comprising monitoring the stability of the pulsed X-ray beam based on a measurement of the voltage of the electrical output signal from the PMT.

48. A method for analyzing ore, comprising: Irradiate the mineral material with a pulsed X-ray beam from a pulsed X-ray source; A beam monitoring device is provided, the beam monitoring device comprising a scintillator that emits light when excited by the X-ray beam and an optoelectronic device that absorbs the light emitted by the scintillator and converts the absorbed light into an electrical output signal; The shutter speed is selectively adjusted between an open configuration and a closed configuration, wherein in the open position, the X-ray beam irradiates the scintillator, and in the closed configuration, the shutter substantially shields the X-ray beam, preventing it from irradiating the scintillator; as well as When the shutter is in the closed configuration, the stability of the pulsed X-ray beam is monitored based on the measurement of the voltage of the electrical output signal from the optoelectronic device.

49. The method of claim 48, wherein the photoelectric device is a silicon photomultiplier tube (SiPM).

50. A method for analyzing ore, comprising: Irradiate the mineral material with a pulsed X-ray beam from a pulsed X-ray source; A beam monitoring device is provided, the beam monitoring device comprising a scintillator that emits light when excited by the X-ray beam and a photomultiplier tube (PMT) that absorbs the light emitted by the scintillator and converts the absorbed light into an electrical output signal. The stability of the pulsed X-ray beam is monitored based on the measurement of the voltage of the electrical output signal from the PMT during each pulse of the X-ray beam.

Images