Device and method for on-line measurement of boron concentration in boron trifluoride complex system

Abstract

The invention provides a device and a method for on-line measurement of boron concentration in a boron trifluoride complex system, and relates to the technical field of boron-10 acid production. The device comprises a neutron emission part, a fluid circulation part, a neutron detection part and a data processing part. The neutron emission part is used for emitting thermal neutron beams, the fluid circulation part is communicated with a fluid pipeline at the bottom of an exchange rectifying tower of the boron trifluoride-anisole complex production process, and the fluid circulation part is of a neutron penetrable structure; the neutron detection part is arranged on the side, away from the neutron emission part, of the fluid circulation part and used for receiving thermal neutron beams penetrating through the boron trifluoride-anisole complex and converting neutron intensity signals into electric signals, and the data processing part is electrically connected with the neutron detection part and used for receiving the electric signals and sending the electric signals to the fluid circulation part. And inverting the concentration of boron-10 in the boron trifluoride-anisole complex according to the attenuation degree of the thermal neutron beam to obtain the total concentration of boron. The device can output the total boron concentration measurement result in real time, and sampling can be carried out without interrupting the production process.

Description

Technical Field

[0001] This invention relates to the field of boron-10 acid production technology, and more particularly to an apparatus and method for online measurement of boron concentration in a boron trifluoride complex system. Background Technology

[0002] In the production process of boron-10 enriched acid for nuclear power, the BF3-anisole system is used to separate boron isotopes. Naturally abundant BF3 gas reacts with liquid anisole as a complexing agent in a complexing tower to form a BF3-anisole complex. The complex then enters the next stage of the exchange distillation tower to continue its chemical exchange reaction with BF3 gas. 10 B gradually transfers from the gas phase to the liquid phase, and finally... 10 B slowly accumulates at the bottom of the exchange distillation column, at a lower concentration. 10 B-abundance BF3 gas was taken from the top of the exchange distillation column; enrichment 10 The anisole complex of B enters the cracking tower and undergoes a decomposition reaction, with high abundance... 10 The BF3 gas product is separated, with a portion introduced to the bottom of the exchange tower for further enrichment, and the remainder collected as product. The decomposed liquid anisole product is purified and recycled. Currently, offline analysis of the boron concentration at the bottom of the exchange tower is required, as real-time monitoring of the boron concentration at the bottom of the exchange tower is not possible. An online boron meter measurement process based on the neutron absorption method can achieve real-time monitoring of the boron concentration in the system. Summary of the Invention

[0003] This invention provides an apparatus and method for online measurement of boron concentration in a boron trifluoride complex system, so as to realize online measurement of boron concentration at the bottom of the exchange tower during the production of boron-10 acid.

[0004] This invention provides an online device for measuring the boron concentration in a boron trifluoride complex system, comprising a neutron emitter, a fluid flow section, a neutron detector, and a data processing unit. The neutron emitter emits a thermal neutron beam. The fluid flow section is connected to the bottom fluid pipeline of the exchange distillation column in the boron trifluoride-anisole complex production process, and the fluid flow section has a neutron-permeable structure to allow the thermal neutron beam emitted by the neutron emitter to pass through. The neutron detector is located on the side of the fluid flow section away from the neutron emitter and is used to receive the thermal neutron beam after it has passed through the boron trifluoride-anisole complex, converting the neutron intensity signal into an electrical signal. The data processing unit is electrically connected to the neutron detector and is used to receive the electrical signal, invert the concentration of boron-10 in the boron trifluoride-anisole complex based on the attenuation degree of the thermal neutron beam, and thus obtain the total boron concentration.

[0005] In one embodiment of the present invention, the neutron emission unit is an isotope neutron source or an accelerator neutron source, and the isotope neutron source includes any one of an americium-beryllium neutron source and a polonium-beryllium neutron source.

[0006] In one embodiment of the present invention, the fluid flow section includes a flow pipe and a connecting flange, the connecting flange being used to achieve a sealed connection between the flow pipe and the fluid pipeline at the bottom of the exchange distillation column.

[0007] In one embodiment of the present invention, the inner wall of the flow tube is provided with a corrosion-resistant coating.

[0008] In one embodiment of the present invention, the neutron detection unit is a thermal neutron detector, including any one or a combination of a helium-3 proportional counter tube and a lithium glass scintillation detector.

[0009] In one embodiment of the present invention, the data processing unit includes a signal amplification unit, an analog-to-digital conversion unit, and a calculation unit; the signal amplification unit is used to amplify the electrical signal output by the neutron detection unit; the analog-to-digital conversion unit is used to convert the amplified analog electrical signal into a digital signal; the calculation unit pre-stores a correspondence model between the neutron attenuation coefficient and the boron-10 concentration, calculates the attenuation degree of the thermal neutron beam based on the digital signal, and substitutes it into the correspondence model to invert the boron-10 concentration.

[0010] In one embodiment of the present invention, the device further includes a shielding and protection section, which is wrapped around the outside of the neutron emitting section, the fluid flow section and the neutron detection section.

[0011] The present invention also provides a method for online measurement of boron concentration in a boron trifluoride complex system, using the above-described apparatus.

[0012] In one embodiment of the present invention, the method includes the following steps: The fluid flow section is sealed and connected to the fluid pipeline at the bottom of the exchange distillation column through a connecting flange, so that the boron trifluoride-anisole complex can flow continuously through the flow pipe. Start the neutron emission unit and adjust the neutron source intensity so that the emitted thermal neutron beam penetrates vertically through the boron trifluoride-anisole complex in the flow tube; The neutron detection unit receives the thermal neutron beam after it passes through the complex, converts the neutron intensity signal into an electrical signal, and transmits it to the data processing unit. The data processing unit amplifies and performs analog-to-digital conversion on the electrical signal to obtain the attenuation of the thermal neutron beam ΔI=I0-I1, where I0 is the initial neutron intensity emitted by the neutron emission unit and I1 is the transmitted neutron intensity received by the neutron detection unit. According to the Lambert-Beer law, combined with the pre-stored correspondence model between the neutron decay coefficient and the boron-10 concentration, the boron-10 concentration C is calculated using the formula C=k×ln(I0 / I1), where k is a correction coefficient related to neutron energy and flow tube size. The total boron concentration in the boron trifluoride-anisole complex was calculated based on the abundance ratio of boron-10 in the total boron, and the measurement results were output in real time.

[0013] In one embodiment of the present invention, the correction coefficient k is calibrated in the following manner: A series of boron trifluoride-anisole standard complexes with known boron-10 concentrations were prepared. The neutron attenuation corresponding to each standard complex was measured using the aforementioned apparatus. A linear fitting model between the neutron attenuation and the boron-10 concentration was established, and the correction coefficient k was determined.

[0014] The beneficial effects of this invention are as follows: The device for online measurement of boron concentration in a boron trifluoride complex system uses a fluid flow section that is directly and sealed to the fluid pipeline at the bottom of the exchange distillation column in the boron trifluoride-anisole complex production process via a connecting flange. This allows the complex to flow continuously and stably through the detection area. Combined with continuous neutron emission from the neutron emission section, real-time signal acquisition from the neutron detection section, and synchronous calculation by the data processing section, the total boron concentration measurement result can be output instantly without interrupting the production process for sampling. Compared to traditional offline detection methods, which have long detection cycles and cannot reflect dynamic changes in concentration, this invention can capture the boron concentration fluctuations of the product at the bottom of the distillation column in real time, providing accurate and timely data support for the dynamic adjustment of production process parameters. This helps improve product quality stability and reduce the defect rate. Attached Figure Description

[0015] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application. It is obvious that the drawings described below are merely some embodiments of this application, and those skilled in the art can obtain other drawings based on these drawings without any inventive effort.

[0016] In the attached diagram: Figure 1 A schematic diagram of an apparatus for online measurement of boron concentration in a boron trifluoride complex system according to an embodiment of the present invention; Figure 2 This is a flowchart illustrating the online measurement of boron concentration in a boron trifluoride complex system provided in one embodiment of the present invention.

[0017] The attached figures are labeled as follows: 100. Neutron emission section; 200. Fluid flow section; 300. Neutron detection section. Detailed Implementation

[0018] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments. Various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. In the absence of conflict, the following embodiments and features in the embodiments can be combined with each other.

[0019] It should be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of the present invention. The drawings only show the components related to the present invention and are not drawn according to the actual number, shape and size of the components in the actual implementation. In the actual implementation, the form, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.

[0020] In the following description, numerous details are explored to provide a more thorough explanation of embodiments of the invention. However, it will be apparent to those skilled in the art that embodiments of the invention may be practiced without these specific details. In other embodiments, well-known structures and devices are shown in block diagram form rather than in detail to avoid obscuring embodiments of the invention.

[0021] Please see Figure 1 This invention provides an online device for measuring boron concentration in a boron trifluoride complex system, comprising a neutron emitter 100, a fluid flow section 200, a neutron detector 300, and a data processing unit (not shown in the figure). The device of this application enables real-time and continuous boron detection. The fluid flow section 200 is directly connected to the fluid pipeline at the bottom of the exchange distillation column, allowing the complex to continuously flow through the detection area. The neutron emitter 100 and the detector collect transmitted neutron signals in real time, and the data processing unit synchronously inverts the boron concentration. This eliminates the need for interrupting the production process sampling and provides immediate feedback on changes in boron content in the distillation column bottom product, offering real-time data support for dynamic control of the production process. Simultaneously, the fluid flow section 200 employs a neutron-permeable structure, allowing the thermal neutron beam to penetrate the fluid for detection without direct contact with the complex. This avoids interference with the chemical properties of the complex and the fluid state of the production pipeline, preventing measurement errors caused by sample contamination and component volatilization during offline sampling. In addition, based on the strong trapping properties of boron-10 for thermal neutrons, the concentration of boron-10 can be inverted by the attenuation of the thermal neutron beam, and the total boron concentration can be calculated by combining the natural abundance of boron-10. The detection principle directly targets boron and is not affected by other components such as anisole in the complex, which effectively improves the specificity and accuracy of boron concentration measurement in complex systems.

[0022] Please see Figure 1In one embodiment, the neutron emitter 100 is used to emit a thermal neutron beam. The fluid flow section 200 is connected to the bottom fluid pipeline of the exchange distillation column in the boron trifluoride-anisole complex production process, so as to allow the boron trifluoride-anisole complex to flow continuously. The fluid flow section 200 is a neutron-permeable structure, allowing the thermal neutron beam emitted by the neutron emitter 100 to pass through. The neutron detector 300 is disposed on the side of the fluid flow section 200 away from the neutron emitter 100, so as to receive the thermal neutron beam after passing through the boron trifluoride-anisole complex and convert the neutron intensity signal into an electrical signal. The data processing unit is electrically connected to the neutron detector 300, so as to receive the electrical signal and inversely determine the concentration of boron-10 in the boron trifluoride-anisole complex based on the attenuation degree of the thermal neutron beam, thereby obtaining the total boron concentration.

[0023] Please see Figure 1 In one embodiment, the neutron emission unit 100 is an isotopic neutron source or an accelerator neutron source. The isotopic neutron source includes any one of an americium-beryllium neutron source or a polonium-beryllium neutron source. Isotopic neutron sources (americium-beryllium, polonium-beryllium) have the characteristic of stable output neutron intensity, requiring no complex external excitation equipment, and can operate continuously for a long time in industrial production environments, reducing the maintenance cost and operational difficulty of the device, and adapting to the continuous operation requirements of chemical production. Accelerator neutron sources can flexibly adjust neutron energy and intensity, and can dynamically adjust emission parameters according to the flow rate and concentration range of the boron trifluoride-anisole complex, ensuring that the attenuation of the thermal neutron beam is within the optimal detection range under different production conditions, improving the adaptability and accuracy of online measurements.

[0024] Please see Figure 1 In one embodiment, the fluid flow section 200 includes a flow pipe and a connecting flange, which is used to achieve a sealed connection between the flow pipe and the fluid pipeline at the bottom of the distillation column. The structure of the flow pipe and the connecting flange enables a quick and sealed connection with the fluid pipeline at the bottom of the distillation column, which avoids safety hazards and measurement errors caused by complex leakage, and facilitates the installation, disassembly and maintenance of the device, adapting to the rapid deployment needs of industrial sites.

[0025] Please see Figure 1 In one embodiment, the inner wall of the flow tube is provided with a corrosion-resistant coating. Boron trifluoride-anisole complex is highly corrosive; the corrosion-resistant coating effectively isolates the complex from direct contact with the inner wall of the flow tube, preventing changes in tube wall thickness and structural damage caused by corrosion. It also avoids changes in neutron penetration efficiency due to tube wall corrosion, ensuring the consistency and stability of detection conditions during long-term continuous online measurement, and reducing the frequency of device replacement and maintenance costs.

[0026] Please see Figure 1In one embodiment, the neutron detection unit 300 is a thermal neutron detector, including any one or a combination of a helium-3 proportional counter tube and a lithium-ion glass scintillation detector. Both the helium-3 proportional counter tube and the lithium-ion glass scintillation detector are high-sensitivity thermal neutron detectors, capable of accurately capturing the weak neutron signal after penetrating the complex. Even under conditions of low boron concentration and small neutron attenuation, they can output a clear and distinguishable electrical signal, improving the lower limit accuracy of online measurements.

[0027] Please see Figure 1 In one embodiment, the data processing unit includes a signal amplification unit, an analog-to-digital conversion unit, and a calculation unit. The signal amplification unit amplifies the electrical signal output by the neutron detector 300. The analog-to-digital conversion unit converts the amplified analog electrical signal into a digital signal. The calculation unit pre-stores a model relating the neutron attenuation coefficient to the boron-10 concentration, calculates the attenuation level of the thermal neutron beam based on the digital signal, and then substitutes the model to retrieve the boron-10 concentration. The signal amplification unit and the analog-to-digital conversion unit can convert the weak analog electrical signal output by the detector into a high-precision digital signal, effectively reducing the impact of electromagnetic interference in the industrial environment on the measurement data and improving the signal-to-noise ratio.

[0028] Please see Figure 1 In one embodiment, the device further includes a shielding protection section that surrounds the neutron emitting section 100, the fluid flow section 200, and the neutron detection section 300. The shielding protection section is made of boron-containing polyethylene or lead alloy. By surrounding the neutron emitting section 100, the fluid flow section 200, and the detection section, the shielding protection section isolates stray neutrons and electromagnetic interference from the external environment, preventing external interference signals from mixing into the detection data. This ensures that the signal received by the neutron detection section 300 comes only from the thermal neutron beam that penetrates the complex, thereby improving the authenticity and reliability of the online measurement data.

[0029] Please see Figure 2 This invention also provides a method for online measurement of boron concentration in a boron trifluoride complex system. Using the aforementioned apparatus, online monitoring of boron concentration can be achieved without altering the existing production process of the boron trifluoride-anisole complex, providing data support for production process optimization. In one embodiment, the method for online measurement of boron concentration in a boron trifluoride complex system includes the following steps: S1. The fluid flow section 200 is sealed and connected to the fluid pipeline at the bottom of the exchange distillation column through a connecting flange, so that the boron trifluoride-anisole complex flows continuously through the flow pipe. S2. Start the neutron emission unit 100 and adjust the neutron source intensity so that the emitted thermal neutron beam penetrates the boron trifluoride-anisole complex in the flow tube perpendicularly. S3, Neutron Detection Unit 300 receives the thermal neutron beam after passing through the complex, converts the neutron intensity signal into an electrical signal and transmits it to the data processing unit; S4. The data processing unit amplifies and performs analog-to-digital conversion on the electrical signal to obtain the attenuation amount ΔI=I0-I1 of the thermal neutron beam, where I0 is the initial neutron intensity emitted by the neutron emission unit 100 and I1 is the transmitted neutron intensity received by the neutron detection unit 300. S5. Based on the Lambert-Beer law and combined with the pre-stored model of the correspondence between the neutron decay coefficient and the boron-10 concentration, the boron-10 concentration C is calculated using the formula C=k×ln(I0 / I1), where k is a correction coefficient related to the neutron energy and the size of the flow tube. S6. Based on the abundance ratio of boron-10 in total boron, calculate the total boron concentration in the boron trifluoride-anisole complex and output the measurement results in real time.

[0030] In one embodiment, the correction coefficient k is determined by: preparing a series of boron trifluoride-anisole standard complexes with known boron-10 concentrations, measuring the neutron attenuation corresponding to each standard complex using an apparatus, establishing a linear fitting model between the neutron attenuation and the boron-10 concentration, and determining the correction coefficient k.

[0031] In this invention, a neutron beam emitted from a neutron source based on the principle of neutron absorption passes through the BF3-anisole complex system, and boron-10 ( 10 B) This method has an extremely high capture cross section for thermal neutrons. When a neutron beam passes through a fluid containing boron-10, its intensity decreases due to absorption by the boron-10. By measuring the degree of neutron beam attenuation, the concentration of boron-10 in the fluid can be deduced, thus obtaining the boron concentration. This measurement method is related to neutron absorption capacity, which better meets the requirements for measuring boron concentration at the bottom of the column. Furthermore, it is not affected by other ions in the system (such as fluorine and chlorine), exhibiting strong anti-interference capabilities.

[0032] This invention relates to an online device for measuring boron concentration in a boron trifluoride complex system. The fluid flow section is directly and sealed to the bottom fluid pipeline of the exchange distillation column in the boron trifluoride-anisole complex production process via a connecting flange, allowing the complex to flow continuously and stably through the detection area. Combined with continuous neutron emission from the neutron emission section, real-time signal acquisition from the neutron detection section, and synchronous calculation by the data processing section, the device can instantly output the total boron concentration measurement result without interrupting the production process for sampling. Compared to traditional offline detection methods, which suffer from long detection cycles and inability to reflect dynamic concentration changes, this invention can capture real-time fluctuations in boron concentration in the bottom product of the distillation column, providing accurate and timely data support for the dynamic adjustment of production process parameters. This helps improve product quality stability and reduce the defect rate.

[0033] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

Claims

1. An apparatus for measuring the concentration of boron in a boron trifluoride complex system on-line, characterized by, include: The neutron emitter is used to emit thermal neutron beams; The fluid flow section is connected to the bottom fluid pipeline of the exchange distillation column in the boron trifluoride-anisole complex production process, and the fluid flow section has a neutron-permeable structure to allow the thermal neutron beam emitted by the neutron emission section to pass through. A neutron detector is located on the side of the fluid flow section away from the neutron emitter, and is used to receive the thermal neutron beam after passing through the boron trifluoride-anisole complex, and to convert the neutron intensity signal into an electrical signal. The data processing unit, electrically connected to the neutron detection unit, is used to receive the electrical signal, invert the concentration of boron-10 in the boron trifluoride-anisole complex based on the attenuation degree of the thermal neutron beam, and then obtain the total boron concentration.

2. The apparatus of claim 1, wherein, The neutron emission unit is an isotopic neutron source or an accelerator neutron source, and the isotopic neutron source includes any one of an americium-beryllium neutron source and a polonium-beryllium neutron source.

3. The apparatus of claim 1, wherein, The fluid flow section includes a flow pipe and a connecting flange, the connecting flange being used to achieve a sealed connection between the flow pipe and the fluid pipeline at the bottom of the exchange distillation column.

4. The apparatus of claim 3, wherein, The inner wall of the flow tube is provided with a corrosion-resistant coating.

5. The apparatus of claim 1, wherein, The neutron detection unit is a thermal neutron detector, including any one or a combination of a helium-3 proportional counter tube and a lithium glass scintillation detector.

6. The apparatus of claim 1, wherein, The data processing unit includes a signal amplification unit, an analog-to-digital conversion unit, and a computing unit. The signal amplification unit is used to amplify the electrical signal output by the neutron detector; The analog-to-digital conversion unit is used to convert the amplified analog electrical signal into a digital signal; The computing unit pre-stores a model of the correspondence between the neutron attenuation coefficient and the boron-10 concentration. It calculates the attenuation degree of the thermal neutron beam based on the digital signal and substitutes it into the model to invert the boron-10 concentration.

7. The apparatus of claim 1, wherein, The device also includes a shielding and protection section, which is wrapped around the outside of the neutron emitting section, the fluid flow section and the neutron detection section.

8. A method for measuring the boron concentration in a boron trifluoride complex system on-line, characterized by, The measurement is performed using the apparatus described in any one of claims 1-7.

9. The method of claim 8, wherein, The method includes the following steps: The fluid flow section is sealed and connected to the fluid pipeline at the bottom of the exchange distillation column via a connecting flange; Start the neutron emission unit and adjust the neutron source intensity so that the emitted thermal neutron beam penetrates vertically through the boron trifluoride-anisole complex in the flow tube; The neutron detection unit receives the thermal neutron beam after it passes through the complex, converts the neutron intensity signal into an electrical signal, and transmits it to the data processing unit. The data processing unit amplifies and performs analog-to-digital conversion on the electrical signal to obtain the attenuation of the thermal neutron beam ΔI=I0-I1, where I0 is the initial neutron intensity emitted by the neutron emission unit and I1 is the transmitted neutron intensity received by the neutron detection unit. According to the Lambert-Beer law, combined with the pre-stored correspondence model between the neutron decay coefficient and the boron-10 concentration, the boron-10 concentration C is calculated using the formula C=k×ln(I0 / I1), where k is a correction coefficient related to neutron energy and flow tube size. The total boron concentration in the boron trifluoride-anisole complex was calculated based on the abundance ratio of boron-10 in the total boron, and the measurement results were output in real time.

10. The method of claim 9, wherein, The correction coefficient k is calibrated in the following manner: A series of boron trifluoride-anisole standard complexes with known boron-10 concentrations were prepared. The neutron attenuation corresponding to each standard complex was measured using the device described above. A linear fitting model between the neutron attenuation and the boron-10 concentration was established, and the correction coefficient k was determined.

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