Method and system for predicting control of hydrogen concentration in high-level liquid waste container, controller, high-level liquid waste tank

Abstract

The application provides a kind of prediction control method and system of hydrogen concentration in high-level liquid waste container, prediction controller and high-level liquid waste tank, belongs to the field of nuclear chemical safety technology.Its prediction control method includes: obtaining the operating state parameters of high-level liquid waste container;Based on the operating state parameters and the first prediction model, calculate the concentration prediction value of hydrogen in the future prediction time domain;According to the preset alarm threshold and the concentration prediction value, generate and execute the control instruction for reducing hydrogen concentration.The prediction control method is used to solve the problem of high dependence on sensors in related technology, which leads to the lag of dilution process control.

Description

Technical Field

[0001] This invention belongs to the field of nuclear chemical safety technology, specifically relating to a method and system for predicting and controlling hydrogen concentration in a high-level radioactive waste container, a predictive controller, and a high-level radioactive waste storage tank. Background Technology

[0002] Currently, hydrogen safety control in high-level radioactive waste storage tanks primarily relies on fixed hydrogen sensors for concentration measurement, supplemented by periodic manual sampling and analysis as a means of replenishing or calibrating the fixed hydrogen sensors. However, manual sampling is inherently slow and highly dependent on sensors. If a sensor experiences accuracy drift, the malfunction cannot be detected in time, leading to delays in dilution process control and potentially causing accidents such as tank combustion or hydrogen explosion. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to address the above-mentioned deficiencies of the prior art by providing a method and system for predicting and controlling hydrogen concentration in a high-level radioactive waste liquid container, a predictive controller, and a high-level radioactive waste liquid storage tank. This method can calculate and predict hydrogen concentration in real time, provide early warnings, and automatically trigger dilution measures to prevent accidents such as combustion and ensure the safe operation of the post-treatment system.

[0004] In a first aspect, the present invention provides a predictive control method for hydrogen concentration in a high-level radioactive waste container, comprising: acquiring operating status parameters of the high-level radioactive waste container; calculating a predicted value of hydrogen concentration in the future prediction time domain based on the operating status parameters and a preset first prediction model; and generating and executing a control command for reducing hydrogen concentration according to a preset alarm threshold and the predicted concentration value.

[0005] In some embodiments, the concentration prediction value includes the spatial concentration distribution prediction value, and the operating status parameters include at least the heat release per unit time of the high-level radioactive waste liquid.

[0006] The first prediction model is used to calculate the hydrogen production rate per unit time based on the heat released per unit time of the high-level radioactive waste liquid, and to calculate the predicted value of the spatial concentration distribution of hydrogen in the future prediction time domain by combining the gas phase space volume, the amount of dilution gas injected, and the gradient coefficient.

[0007] In some embodiments, after calculating the predicted value of hydrogen concentration in the future prediction time domain, and before generating and executing a control command for reducing hydrogen concentration based on a preset alarm threshold and the predicted concentration value, the method for predicting and controlling the hydrogen concentration in a high-level radioactive waste container further includes: updating the predicted value of hydrogen concentration in the future preset time domain according to a preset second prediction model during the dilution gas injection process.

[0008] In some embodiments, the method for predicting and controlling hydrogen concentration in a high-level radioactive waste container further includes: obtaining measured values ​​of hydrogen concentration at different vertical heights within the high-level radioactive waste container; calculating the deviation between the measured concentration value and the predicted concentration value at the same vertical height at the current moment; comparing the deviation with an error threshold; and in response to a deviation exceeding the error threshold, iteratively optimizing the gradient coefficients in the first and second prediction models using a parameter estimation method.

[0009] In some embodiments, a control command for reducing hydrogen concentration is generated and executed based on a preset alarm threshold and a concentration prediction value. Specifically, this includes: comparing the current measured concentration value and the corresponding current predicted concentration value with the preset alarm threshold; and generating and executing an opening command for the inlet valve of the dilution device in response to the measured concentration value or the concentration prediction value being greater than or equal to the alarm threshold.

[0010] In some embodiments, the method for predicting and controlling the hydrogen concentration in a high-level radioactive waste container further includes: determining whether the measured concentration value exceeds the physically reasonable range; determining whether the measured concentration value remains empty for a preset time period; determining whether the change in the measured concentration value exceeds a change threshold for a preset time period; and, in response to the determination result of any of the above determinations being yes, diagnosing a sensor fault and triggering a fault safety response.

[0011] Secondly, the present invention also provides a predictive controller for hydrogen concentration in a high-level radioactive waste container, comprising: an acquisition module for acquiring operating status parameters of the high-level radioactive waste container; a prediction module connected to the acquisition module for calculating a predicted hydrogen concentration value in the future prediction time domain based on the operating status parameters and a preset first prediction model; and a generation module connected to the prediction module for generating and executing control commands to reduce the hydrogen concentration according to a preset alarm threshold and the predicted concentration value.

[0012] In some embodiments, the prediction module includes a first prediction model. The first prediction model is used to calculate the hydrogen production rate per unit time based on the heat released per unit time of the high-level radioactive waste liquid, and to calculate the predicted value of the spatial concentration distribution of hydrogen in the future prediction time domain by combining the gas phase space volume, the amount of dilution gas injected, and the gradient coefficient.

[0013] Thirdly, the present invention also provides a predictive control system for hydrogen concentration in a high-level radioactive waste liquid container, comprising: a predictive controller for hydrogen concentration in a high-level radioactive waste liquid container as described in the second aspect, and a hydrogen monitoring device, a liquid level sensor, a radiation sensor, an inlet valve of a dilution device, and an inlet flow sensor electrically connected thereto.

[0014] Fourthly, the present invention also provides a high-level radioactive waste liquid storage tank, including a tank body, and a prediction and control system for hydrogen concentration in the high-level radioactive waste liquid container as described in the third aspect. The prediction and control system is integrated on or connected to the tank body and is used to realize the prediction and safe control of hydrogen concentration in the tank body.

[0015] The present invention provides a method and system for predicting and controlling hydrogen concentration in a high-level radioactive waste container, a predictive controller, and a high-level radioactive waste storage tank. Based on the real-time operating parameters of the high-level radioactive waste container and a first predictive model, the system predicts the hydrogen concentration in the future time domain. Based on the prediction results, it generates and executes control commands to reduce the hydrogen concentration. Through a closed-loop system of real-time parameter acquisition, predictive model calculation, dynamic prediction, and intelligent control, the system achieves advance prediction and dilution control of hydrogen concentration in the high-level radioactive waste container, avoiding the lag problem in dilution control caused by relying entirely on sensor detection of hydrogen concentration, thereby ensuring the safe operation of the system.

[0016] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of the present invention, nor is it intended to limit the scope of the invention. Other features of the invention will become readily apparent from the following description. Attached Figure Description

[0017] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used together with the embodiments of the invention to explain the invention and do not constitute a limitation thereof. The above and other features and advantages will become more apparent to those skilled in the art from the detailed description of exemplary embodiments with reference to the accompanying drawings, in which: Figure 1 A flowchart illustrating a method for predicting and controlling hydrogen concentration in a high-level radioactive waste liquid container, provided in an embodiment of the present invention. Figure 2 A schematic flowchart illustrating another method for predicting and controlling hydrogen concentration in a high-level radioactive waste liquid container provided in an embodiment of the present invention. Figure 3 This is a schematic diagram of the structure of a predictive control system for hydrogen concentration in a high-level radioactive waste liquid container, provided in an embodiment of the present invention. Detailed Implementation

[0018] To enable those skilled in the art to better understand the technical solutions of the present invention, exemplary embodiments of the present invention are described below in conjunction with the accompanying drawings, including various details of the embodiments of the present invention to aid understanding. These should be considered merely exemplary. Therefore, those skilled in the art should recognize that various changes and modifications can be made to the embodiments described herein without departing from the scope and spirit of the present invention. Similarly, for clarity and brevity, descriptions of well-known functions and structures are omitted in the following description.

[0019] Where there is no conflict, the various embodiments of the present invention and the features thereof may be combined with each other.

[0020] As used herein, the term “and / or” includes any and all combinations of one or more related enumerated entries.

[0021] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the invention. As used herein, the singular forms “a” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will also be understood that when the terms “comprising” and / or “made of” are used in this specification, the presence of the stated feature, integral, step, operation, element, and / or component is specified, but the presence or addition of one or more other features, integrals, steps, operations, elements, components, and / or groups thereof is not excluded. Terms such as “connected” or “linked” are not limited to physical or mechanical connections but can include electrical connections, whether direct or indirect.

[0022] Unless otherwise specified, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art. It will also be understood that terms such as those defined in commonly used dictionaries should be interpreted as having the meaning consistent with their meaning in the context of the relevant art and the invention, and will not be interpreted as having an idealized or overly formal meaning unless expressly so defined herein.

[0023] Firstly, such as Figure 1 As shown, this embodiment provides a method for predicting and controlling the hydrogen concentration in a high-level radioactive waste container, including: Step 101: Obtain the operating status parameters of the high-level radioactive waste container.

[0024] Step 102: Based on the operating status parameters and the preset first prediction model, calculate the predicted value of hydrogen concentration in the future prediction time domain.

[0025] Step 103: Generate and execute control commands to reduce hydrogen concentration based on preset alarm thresholds and concentration prediction values.

[0026] The first prediction model is used to calculate the predicted hydrogen concentration in the future prediction time domain based on real-time operating status parameters. Therefore, the first prediction model can be a hybrid model of mechanism and experience, or a data-based empirical model, such as a traditional machine learning model or a neural network model. The control command for reducing the hydrogen concentration can be a dilution gas injection command, that is, controlling the valve to inject dilution gas into the gas phase space inside the high-level radioactive waste liquid container at a specific flow rate. The dilution gas includes inert gas (such as nitrogen) or clean air. It can also be an exhaust or extraction command, that is, opening the exhaust valve or starting the extraction pump to actively exhaust the gas in the high-level radioactive waste liquid container to the waste gas treatment system.

[0027] In this embodiment, based on the real-time operating status parameters of the high-level radioactive waste container and a first prediction model, the predicted hydrogen concentration in the future time domain is predicted in real time. Control commands to reduce the hydrogen concentration are generated and executed based on the prediction results. Through a closed-loop system of real-time parameter acquisition, prediction model calculation, dynamic prediction, and intelligent control, the concentration of hydrogen in the high-level radioactive waste container can be predicted in advance and diluted in advance. This avoids the lag problem in dilution control caused by relying entirely on sensors to detect hydrogen concentration, thereby ensuring the safe operation of the system.

[0028] In some embodiments, the concentration prediction value includes the spatial concentration distribution prediction value, and the operating status parameters include at least the heat release per unit time of the high-level radioactive waste liquid.

[0029] The first prediction model is used to calculate the hydrogen production rate per unit time based on the heat released per unit time of the high-level radioactive waste liquid, and to calculate the predicted value of the spatial concentration distribution of hydrogen in the future prediction time domain by combining the gas phase space volume, the amount of dilution gas injected, and the gradient coefficient.

[0030] In related technologies, fixed hydrogen sensors can only monitor the concentration at local points and cannot reflect the spatial concentration distribution of hydrogen within the high-level radioactive waste container. To make risk perception more refined and improve the global visibility of the system status within the high-level radioactive waste container, the concentration prediction value in this embodiment includes a spatial concentration distribution prediction value, and the first prediction model is specifically a hybrid model of mechanism and experience.

[0031] In some embodiments, the first prediction model is specifically: , (1) in, This represents the predicted spatial concentration distribution. Indicates the vertical height from the surface of the high-level radioactive waste liquid. This represents any point in the future prediction time domain. This indicates the hydrogen production rate per unit time (unit: m³ / s). Represents the volume of the gas phase space. Indicates the amount of dilution gas injected. Q (气) Indicates the inlet air flow rate of the dilution device (unit: Nm³). 3 / s), Indicates the intake time of the dilution device. This represents the gradient coefficient. It should be noted that the gradient coefficient characterizes the distribution of hydrogen concentration with altitude, and its initial value can be determined through prior experiments or numerical simulations. k 0.

[0032] For example, if the high-level radioactive waste container is cylindrical, then the volume of the gas phase space is... V 气 =πR²h 气 ,in, h 气 =Hh 液 R represents the radius of the high-level radioactive waste container, H represents the height of the container, and h represents the height of the container. 液 The level of the high-level waste liquid in the container is indicated by a level sensor and can be measured in real time. 气 This indicates the gas phase height. It should be noted that R and H are structural parameters of the high-level radioactive waste container, which can be preset in the controller.

[0033] In some embodiments, the heat released per unit time by the high-level radioactive waste liquid is collected in real time by a radiation sensor. Wt (Unit: J / s) This operating status parameter reflects the radiant energy absorbed by the waste liquid, based on the heat released per unit time of the collected high-level radioactive waste liquid. Wt The hydrogen production rate per unit time is calculated according to equation (2). (Unit: m³ / s): (2) Among them, 6.242×10 18 Here is the conversion factor between J and eV (1J = 6.242 × 10¹). 8 eV), 6.022×10²³ is Avogadro's constant (number of molecules / mol), and 0.0224 is the volume of 1 mol of gas under standard conditions (unit: m³ / mol). The radiolysis hydrogen production rate of the high-level radioactive waste liquid (unit: number of molecules / 100eV, determined by the high-level radioactive waste liquid source term).

[0034] like Figure 2As shown, in some embodiments, the operating status parameters also include the liquid level height of the high-level radioactive waste liquid, which can be measured in real time by a liquid level sensor. The concentration prediction value also includes the average concentration prediction value. The first prediction model is also used to calculate the hydrogen production rate per unit time based on the heat released per unit time of the high-level radioactive waste liquid, and to calculate the average concentration prediction value of hydrogen in the future prediction time domain by combining the gas phase space volume and the dilution gas injection amount. The average concentration prediction value is shown in equation (3): , (3) It should be noted that, considering the concentration gradient caused by the lower density of hydrogen compared to air, the hydrogen concentration in the gas phase of the high-level radioactive waste container exhibits a gradient. Therefore, the hydrogen concentration at different vertical heights can be calculated according to equation (3) to obtain the predicted spatial concentration distribution. That is, the first prediction model can be derived from equation (3). .

[0035] In this embodiment, the concentration prediction values ​​include average concentration prediction values ​​and spatial concentration distribution prediction values. Compared with traditional single-point sensor detection technology, the overall average value is used to grasp the macro-risk level of the system, and the spatial distribution is used to locate the micro-risk sources, thus constructing a complete risk perception map. Furthermore, by using the two prediction values ​​for cross-validation, it can keenly identify early risk patterns of "overall stability and local mutations", which greatly improves the reliability of early warning.

[0036] In some embodiments, after calculating the predicted value of hydrogen concentration in the future prediction time domain, and before generating and executing a control command for reducing hydrogen concentration based on a preset alarm threshold and the predicted concentration value, the method for predicting and controlling the hydrogen concentration in a high-level radioactive waste container further includes: updating the predicted value of hydrogen concentration in the future preset time domain according to a preset second prediction model during the dilution gas injection process.

[0037] In related technologies, it is difficult to track concentration changes in real time during the dilution gas injection process, and the safety and reliability need to be improved to achieve comprehensive early warning. Therefore, the second prediction model in this embodiment is used to update the predicted value of hydrogen concentration in a future preset time domain based on the real-time volume change of the injected dilution gas.

[0038] In some embodiments, the concentration prediction value is dynamically updated using equation (4), i.e., the second prediction model is specifically as follows: , (4) In some embodiments, after updating the predicted hydrogen concentration within a preset future time domain, the method for predicting and controlling the hydrogen concentration in the high-level radioactive waste container further includes: dynamically adjusting the inlet flow rate of the dilution device based on the deviation between the updated predicted concentration value and a preset alarm threshold. By dynamically adjusting the inlet flow rate of the dilution device, the greater the deviation, the stronger the adjustment action (such as the inlet flow rate), achieving a precise match between the control response and the severity of the risk. Based on this nonlinear control, the duration of the risk can be greatly reduced, significantly improving the dynamic response speed and efficiency of the control.

[0039] Specifically, according to With alarm threshold C 0 deviation dynamic adjustment (Increase flow rate if deviation > 1%, decrease flow rate if deviation < 0.5%), until... Close the air inlet valve of the dilution device at the appropriate time.

[0040] In some embodiments, the method for predicting and controlling the hydrogen concentration inside a high-level radioactive waste container further includes: Step 201: Obtain the measured concentration of hydrogen at different vertical heights inside the high-level radioactive waste container.

[0041] Step 202: Calculate the deviation between the measured concentration value and the predicted concentration value at the current time and the same vertical height.

[0042] Step 203: Compare the deviation with the error threshold.

[0043] Step 204: In response to the deviation being greater than the error threshold, the gradient coefficients in the first and second prediction models are iteratively optimized using the parameter estimation method.

[0044] In related technologies, calibrating fixed hydrogen sensors based on manual sampling and analysis suffers from latency. This embodiment calibrates the first and second prediction models in real-time and dynamically based on the measured concentration values ​​of the hydrogen sensor, improving the accuracy of the prediction results. The parameter estimation methods include least squares, gradient descent, and maximum likelihood estimation.

[0045] Specifically, for the same moment t same vertical height z Calculate the measured concentration value Deviation from concentration prediction Start dynamic calibration logic: when (Error threshold), the model parameters of the first and second prediction models remain unchanged, when The gradient coefficients are iteratively optimized using the least squares method. ,make Fitting The updated Used for prediction at the next time point. Alternatively, based on parameters from each concentration exceedance and control process, the gradient coefficient can be optimized using machine learning algorithms. The alarm threshold C0 can improve prediction accuracy and control efficiency.

[0046] For example, at different heights in the gas phase space of a high-level radioactive waste container. z Install a hydrogen sensor and equip the inlet pipeline of the dilution device with a pneumatic valve. When the hydrogen sensor collects the concentration... When the alarm threshold is reached, the valve is opened, and the flow rate of dilution gas entering the container is measured by the intake flow sensor. Q 气 When the hydrogen concentration falls below the alarm threshold, the valve is closed to stop the gas intake. It also includes a first prediction model, which is used to predict the gaseous hydrogen concentration inside the container. The system plots hydrogen concentration curves over time, including the overall concentration curve (i.e., the average concentration prediction curve) and gradient concentration curves at different altitudes (i.e., the spatial concentration distribution prediction curve). It dynamically predicts the concentration trend in the future prediction time domain and uses measured concentration values ​​through dynamic calibration logic. For prediction models The gradient coefficients are iteratively optimized in real time. This constructs a closed-loop system of "real-time parameter acquisition - prediction model calculation - sensor data calibration - dynamic prediction - intelligent control," integrating the predicted values ​​of the first prediction model with the measured values ​​of real-time sensors. Dynamic model calibration is achieved through data comparison and analysis. Simultaneously, a real-time prediction function for the dilution process (i.e., the second prediction model function) is designed to address the high sensor dependence and lag in dilution control in traditional methods, significantly improving the hydrogen explosion risk prevention capability of high-level radioactive waste storage tanks.

[0047] In some embodiments, control commands for reducing hydrogen concentration are generated and executed based on preset alarm thresholds and concentration prediction values, specifically including: The measured concentration value at the current moment and the corresponding predicted concentration value at the current moment are compared with the preset alarm thresholds respectively; In response to a measured or predicted concentration value being greater than or equal to an alarm threshold, a command to open the inlet valve of the dilution device is generated and executed.

[0048] In this embodiment, due to the extremely high safety requirements of the post-processing system, redundant control based on concentration measurement and prediction is adopted. For example... Figure 2 As shown, if the concentration prediction value includes both the average concentration prediction value and the spatial concentration distribution prediction value, then if the corresponding average concentration prediction value, spatial concentration distribution prediction value, or measured concentration value at the current moment exceeds the alarm threshold, an opening command will be generated and executed to open the intake valve of the dilution device. If the concentration prediction value only includes the spatial concentration distribution prediction value, then the real-time measured concentration value will be used. and concentration prediction values The concentration curve is compared with the alarm threshold C0. If the concentration curve touches or exceeds C0 at any time, an alarm signal is triggered. When the alarm signal is triggered, the control system automatically opens the air inlet valve at the top of the high-level radioactive waste container to introduce inert gas (such as nitrogen) or clean air to reduce the hydrogen concentration in the gas phase space and the air inlet flow rate. Q (气) The system dynamically adjusts based on the degree of concentration exceeding the limit. When the hydrogen concentration in the gas phase space is lower than the alarm threshold (e.g., 2%), the intake valve is closed to complete a closed-loop control for preventing hydrogen explosion.

[0049] In some embodiments, a control command for reducing hydrogen concentration is generated and executed based on a preset alarm threshold and a concentration prediction value. Specifically, this includes: comparing the current measured concentration value and the corresponding predicted concentration value for the next moment with the preset alarm threshold; and generating and executing a command to open the inlet valve of the dilution device in response to the measured or predicted concentration value being greater than or equal to the alarm threshold. That is, using the current measured concentration value and the predicted concentration value for the next moment for judgment can also solve the problems in related technologies and achieve the prediction effect.

[0050] In some embodiments, the method for predicting and controlling the hydrogen concentration in a high-level radioactive waste container further includes: determining whether the measured concentration value exceeds the physically reasonable range; determining whether the measured concentration value remains empty for a preset time period; determining whether the change in the measured concentration value exceeds a change threshold for a preset time period; and, in response to the determination result of any of the above determinations being yes, diagnosing a sensor fault and triggering a fault safety response.

[0051] In related technologies, relying on a single fixed hydrogen sensor carries the risk of monitoring interruption in the event of sensor failure. For example... Figure 2 As shown, this embodiment integrates a fault redundancy mechanism that combines a predictive model with a hydrogen sensor. Specifically, it compares both the measured and predicted concentration values ​​with alarm thresholds simultaneously to generate and execute an opening command for the inlet valve of the dilution device. The controller also includes sensor fault diagnosis functionality. A hydrogen sensor fault is determined when the hydrogen sensor data meets any of the following conditions: (1) The data exceeds the physical reasonable range (e.g.) <0 or >100%); (2) No data output for 5 consecutive seconds or fluctuation range > 5% / s.

[0052] When a sensor malfunction is detected, the controller automatically switches to "prediction-driven mode" and continues calculations based on the model parameters from the most recently calibrated model. This ensures that concentration predictions are not interrupted.

[0053] The method for predicting and controlling hydrogen concentration in a high-level radioactive waste container in this embodiment collects the operating status parameters of the high-level radioactive waste container in real time. Based on the hydrogen release rate formula (2) and the hydrogen concentration calculation formula (3) in the container, it dynamically calculates the predicted value formula (1) of the hydrogen spatial concentration distribution in the container. When the concentration reaches the preset alarm threshold, it automatically triggers the dilution device to introduce gas, thereby achieving precise control of hydrogen concentration and effectively preventing the risk of hydrogen explosion. It has the following effects: (1) By collecting operating status parameters in real time and calculating hydrogen concentration, combined with gradient distribution model, the spatial distribution and dynamic changes of hydrogen in the container can be accurately reflected, solving the problems of lag and locality of traditional monitoring, and greatly improving the real-time performance and accuracy of hydrogen concentration measurement.

[0054] (2) Achieve proactive early warning and automatic control, identify risks in advance based on dynamic prediction, and automatically trigger dilution measures through a closed-loop control system without human intervention, thereby greatly improving the speed of emergency response and reducing the risk of human operation.

[0055] (3) The reliability of hydrogen explosion prevention control is enhanced. When the sensor fails, it automatically switches to the prediction-driven mode to avoid missed detection of risks caused by monitoring interruption, thus improving system availability.

[0056] (4) It has high adaptability and high safety. Through preset parameters and feedback optimization mechanism, it can be adapted to containers of different specifications and waste liquid characteristics. By strictly controlling the hydrogen concentration below the lower explosive limit, the risk of hydrogen explosion is eliminated from the source, ensuring the safety of nuclear facilities and personnel.

[0057] Example: The following is an example of a method for predicting and controlling hydrogen concentration in high-level radioactive waste containers. Specifically, it uses a high-level radioactive waste storage tank from a certain project as an example to describe the implementation process in detail: For a certain project, the storage tank has a radius R = 2m, a tank height H = 5m, and a gas phase height h. 气 =3m (gas phase volume) V 气 =37.7m³). Hydrogen production rate from radioactive waste liquid =0.424 molecules / 100 eV, heat released per unit time Wt =367000J / s (real-time data acquisition); Alarm threshold C0=2%, initial value of gradient coefficient k 0 = 0.1m - ¹(determined through prior computational fluid dynamics (CFD) simulations), the hydrogen sensors are respectively arranged at... z =1m, 2m.

[0058] The hydrogen release rate was calculated based on the above parameters:

[0059] Based on the spatial concentration distribution predictions calculated by the first prediction model, a curve showing the change of hydrogen concentration over time is plotted to dynamically predict the concentration change trend in the future prediction time domain.

[0060] When t=3000s , Measured concentration value from the sensor ,optimization k =0.105m - ¹, After the update The concentration is consistent with the measured value.

[0061] like z If a sensor malfunctions at a distance of 2m (e.g., data jumps to 5%), after determining that a sensor malfunction has occurred, switch to prediction-driven mode. k =0.105m - ¹Continuing the calculation, when t=3500s, The system is triggered to automatically open the intake valve of the dilution device, allowing nitrogen or compressed air to be introduced at a flow rate of 0.5 m³ / s.

[0062] Introduce dilution gas t 气 =100s later, calculate using equation (4) ,reduce Q 气 up to 0.2m 3 / s; when t 气 =150s At this point, the concentration is below 0.8%. Close the air inlet valve of the dilution device to complete one control cycle.

[0063] Secondly, this embodiment provides a predictive controller for hydrogen concentration inside a high-level radioactive waste container, comprising: The acquisition module is used to acquire the operating status parameters of the high-level radioactive waste container.

[0064] The prediction module, connected to the acquisition module, is used to calculate the predicted concentration of hydrogen in the future prediction time domain based on the operating status parameters and the preset first prediction model.

[0065] The generation module, connected to the prediction module, is used to generate and execute control commands to reduce the hydrogen concentration based on preset alarm thresholds and concentration prediction values.

[0066] In some embodiments, the prediction module includes a first prediction model.

[0067] The first prediction model is used to calculate the hydrogen production rate per unit time based on the heat released per unit time of the high-level radioactive waste liquid, and to calculate the predicted value of the spatial concentration distribution of hydrogen in the future prediction time domain by combining the gas phase space volume, the amount of dilution gas injected, and the gradient coefficient.

[0068] In some embodiments, the prediction module further includes a second prediction model.

[0069] The prediction module is also used to update the predicted concentration of hydrogen in a future preset time domain according to a preset second prediction model during the dilution gas injection process.

[0070] In some embodiments, the prediction module is further configured to obtain the measured concentration values ​​of hydrogen at different vertical heights inside the high-level radioactive waste container, calculate the deviation between the measured concentration value and the predicted concentration value at the same vertical height at the current moment, compare the deviation with an error threshold, and in response to the deviation being greater than the error threshold, iteratively optimize the gradient coefficients in the first prediction model and the second prediction model using a parameter estimation method.

[0071] In some embodiments, the generation module (corresponding to) Figure 3 The interlocking control module is used to compare the current measured concentration value and the corresponding current predicted concentration value with the preset alarm threshold. In response to the measured concentration value or the predicted concentration value being greater than or equal to the alarm threshold, it generates and executes an opening command for the intake valve of the dilution device.

[0072] In some embodiments, the predictive controller further includes a fault diagnosis module, which is used to determine whether the measured concentration value exceeds the physically reasonable range, whether the measured concentration value remains empty for a preset time period, whether the change range of the measured concentration value exceeds the change threshold, and, in response to the determination result of any of the above determinations being yes, to diagnose a sensor fault and trigger a fault safety response.

[0073] It should be noted that the functions of each module in the hydrogen concentration prediction controller in the high-level radioactive waste container of this embodiment correspond to the contents of the first aspect, and will not be described in detail here.

[0074] like Figure 3 As shown, in a third aspect, this embodiment provides a predictive control system for hydrogen concentration in a high-level radioactive waste liquid container, including: a predictive controller as described in the second aspect, and a hydrogen monitoring device, a liquid level sensor, a radiation sensor, an inlet valve of a dilution device, and an inlet flow sensor electrically connected thereto.

[0075] Fourthly, this embodiment provides a high-level radioactive waste liquid storage tank, including a tank body and a predictive control system as described in the third aspect. The predictive control system is integrated on or connected to the tank body to achieve prediction and safe control of hydrogen concentration in the tank body.

[0076] The controllers, control systems, and high-level radioactive waste storage tanks provided in the second to fourth aspects all combine real-time calculation, dynamic prediction, and automatic control. By integrating the prediction model with real-time sensor data, dynamic calibration and fault redundancy are achieved, while the real-time prediction of the dilution process is optimized, significantly improving the robustness and control accuracy of the system.

[0077] Those skilled in the art will understand that all or some of the steps, systems, and apparatuses disclosed above, and their functional modules / units, can be implemented as software, firmware, hardware, or suitable combinations thereof. In hardware implementations, the division between functional modules / units mentioned above does not necessarily correspond to the division of physical components; for example, a physical component may have multiple functions, or a function or step may be performed collaboratively by several physical components. Some or all physical components can be implemented as software executed by a processor, such as a central processing unit, digital signal processor, or microprocessor, or as hardware, or as integrated circuits, such as application-specific integrated circuits (ASICs).

[0078] Example embodiments have been disclosed herein, and while specific terminology has been used, it is for illustrative purposes only and should be construed as such, and is not intended to be limiting. In some instances, it will be apparent to those skilled in the art that features, characteristics, and / or elements described in conjunction with particular embodiments may be used alone, or in combination with features, characteristics, and / or elements described in conjunction with other embodiments, unless otherwise expressly indicated. Therefore, those skilled in the art will understand that various changes in form and detail may be made without departing from the scope of the invention as set forth in the appended claims.

Claims

1. A method for predicting and controlling hydrogen concentration in a high-level radioactive waste container, characterized in that, include: Obtain the operating status parameters of the high-level radioactive waste container; Based on the operating status parameters and the preset first prediction model, the predicted value of hydrogen concentration in the future prediction time domain is calculated. Based on the preset alarm threshold and the concentration prediction value, control commands for reducing hydrogen concentration are generated and executed.

2. The method for predicting and controlling hydrogen concentration in a high-level radioactive waste container according to claim 1, characterized in that, The concentration prediction values ​​include spatial concentration distribution prediction values, and the operating status parameters include at least the heat release per unit time of the high-level radioactive waste liquid. The first prediction model is used to calculate the hydrogen production rate per unit time based on the heat released per unit time of the high-level radioactive waste liquid, and to calculate the predicted value of the spatial concentration distribution of hydrogen in the future prediction time domain by combining the gas phase space volume, the amount of dilution gas injected, and the gradient coefficient.

3. The method for predicting and controlling hydrogen concentration in a high-level radioactive waste container according to claim 2, characterized in that, After calculating the predicted hydrogen concentration in the future prediction time domain, and before generating and executing a control command to reduce the hydrogen concentration based on a preset alarm threshold and the predicted concentration, the method further includes: During the dilution gas injection process, the predicted concentration of hydrogen in the future preset time domain is updated according to the preset second prediction model.

4. The method for predicting and controlling hydrogen concentration in a high-level radioactive waste container according to any one of claims 2 or 3, characterized in that, Also includes: Obtain the measured concentration of hydrogen at different vertical heights inside the high-level radioactive waste container; Calculate the deviation between the measured concentration value and the predicted concentration value at the same vertical height at the current moment; The deviation is compared with an error threshold. In response to the deviation being greater than the error threshold, the gradient coefficients in the first prediction model and the second prediction model are iteratively optimized using a parameter estimation method.

5. The method for predicting and controlling hydrogen concentration in a high-level radioactive waste container according to claim 4, characterized in that, The step of generating and executing control commands to reduce the hydrogen concentration based on a preset alarm threshold and the predicted concentration value specifically includes: The measured concentration value at the current moment and the corresponding predicted concentration value at the current moment are compared with the preset alarm thresholds respectively; In response to the measured concentration value or the predicted concentration value being greater than or equal to the alarm threshold, an opening command for the air inlet valve of the dilution device is generated and executed.

6. The method for predicting and controlling hydrogen concentration in a high-level radioactive waste container according to claim 4, characterized in that, Also includes: Determine whether the measured concentration value exceeds the physically reasonable range; Determine whether the measured concentration value remains empty for a preset time period; Determine whether the change in the measured concentration value within a preset time period exceeds a change threshold; If any of the above judgments is true, a sensor fault is diagnosed and a fail-safe response is triggered.

7. A predictive controller for hydrogen concentration inside a high-level radioactive waste container, characterized in that, include: The acquisition module is used to acquire the operating status parameters of the high-level radioactive waste container; The prediction module, connected to the acquisition module, is used to calculate the predicted value of hydrogen concentration in the future prediction time domain based on the operating status parameters and the preset first prediction model. The generation module, connected to the prediction module, is used to generate and execute control commands to reduce the hydrogen concentration based on a preset alarm threshold and the predicted concentration value.

8. The predictive controller according to claim 7, characterized in that, The prediction module includes a first prediction model. The first prediction model is used to calculate the hydrogen production rate per unit time based on the heat released per unit time of the high-level radioactive waste liquid, and to calculate the predicted value of the spatial concentration distribution of hydrogen in the future prediction time domain by combining the gas phase space volume, the amount of dilution gas injected, and the gradient coefficient.

9. A predictive control system for hydrogen concentration inside a high-level radioactive waste container, characterized in that, include: The predictive controller of claim 7, and the hydrogen monitoring device, liquid level sensor, radiation sensor, inlet valve of dilution device, and inlet flow sensor electrically connected thereto.

10. A high-level radioactive waste liquid storage tank, characterized in that, The system includes a tank and, as described in claim 9, a predictive control system integrated on or connected to the tank for predicting and safely controlling the hydrogen concentration within the tank.

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