A method and device for controlling lithium ion concentration in a primary circuit system of a nuclear power plant

Abstract

The present application particularly relates to a method for controlling lithium ion concentration in a primary loop system of a nuclear power plant, comprising: calculating a target lithium ion concentration in the primary loop water of the nuclear power plant; obtaining an actual lithium ion concentration in the primary loop water of the nuclear power plant; determining a relationship between the target lithium ion concentration and the actual lithium ion concentration in the primary loop water of the nuclear power plant; if the target lithium ion concentration is greater than the actual lithium ion concentration, performing a lithium addition operation on the primary loop water of the nuclear power plant; and if the target lithium ion concentration is less than the actual lithium ion concentration, performing a lithium removal operation on the primary loop water of the nuclear power plant. The present application also relates to a device for controlling lithium ion concentration in a primary loop system of a nuclear power plant, a computer device and a storage medium, which are used to implement the steps of the above method. The present application realizes online real-time monitoring and automatic adjustment of lithium ion concentration in a primary loop system of a nuclear power plant, and is more convenient and efficient to operate, while reducing the safety hazards of high-radiation detection samples to operators.

Description

Technical Field

[0001] This invention relates to the field of nuclear power plant detection equipment technology, and in particular to a method and device for controlling lithium-ion concentration in the primary loop system of a nuclear power plant. Background Technology

[0002] The primary coolant loop (PLL) system in a pressurized water reactor (PWR) nuclear power plant is used to directly cool the reactor core and transfer the heat generated by the core to the secondary coolant loop. It is characterized by high temperature, high pressure, and high radioactivity. As a critical component of the nuclear power plant, the proper operation of the primary coolant loop is a key factor in ensuring the safety and efficiency of the nuclear reaction. To maintain the pH value of the primary coolant loop at recommended levels throughout the cycle, lithium hydroxide is added to the primary coolant loop cooling medium to ensure the safety of the primary coolant loop pressure boundary materials and reduce the radiation dose levels to personnel and equipment. When the pH is maintained within a specific range, the corrosion of materials in the loop and the migration of corrosion products after core activation can be limited to optimal levels. Therefore, the detection and control of lithium ion concentration in the primary coolant loop system is extremely critical.

[0003] Currently, the control of lithium-ion concentration in primary loop systems primarily relies on daily offline manual sampling, detection, and offline chemical dosing adjustments. However, due to the presence of highly radioactive substances in the primary loop water, this method is cumbersome, inefficient in terms of detection, and poses significant safety risks. Therefore, research on online real-time monitoring and control of lithium-ion concentration in primary loop systems is of great importance. Summary of the Invention

[0004] The purpose of this invention is to solve the problems of cumbersome operation, low efficiency and high safety risks of existing lithium-ion concentration control methods in the primary loop system of nuclear power plants. It provides a method and device for controlling lithium-ion concentration in the primary loop system of nuclear power plants, realizing online real-time monitoring and automatic adjustment of lithium-ion concentration in the primary loop system of nuclear power plants, making operation more convenient and efficient, while reducing the safety hazards of highly radioactive test samples to operators.

[0005] To achieve the above objectives, the present invention provides a method for controlling lithium-ion concentration in the primary loop system of a nuclear power plant, comprising the following steps:

[0006] S1. Calculate the target lithium-ion concentration C1 in the primary loop water of a nuclear power plant;

[0007] S2. Obtain the actual lithium-ion concentration C0 in the primary loop water of the nuclear power plant;

[0008] S3. Determine the relationship between the target lithium ion concentration C1 and the actual lithium ion concentration C0 in the primary loop water of a nuclear power plant.

[0009] If the target lithium-ion concentration C1 in the primary loop water of a nuclear power plant is greater than the actual lithium-ion concentration C0, then lithium addition is performed on the primary loop water of the nuclear power plant.

[0010] If the target lithium-ion concentration C1 in the primary loop water of a nuclear power plant is less than the actual lithium-ion concentration C0, then lithium removal operations are performed on the primary loop water of the nuclear power plant.

[0011] As one feasible method, S1, calculating the target lithium-ion concentration C1 in the primary loop water of a nuclear power plant includes the following steps:

[0012] S11. Construct a boron-lithium coordination relationship diagram for borate and lithium ion concentrations in the primary loop water of a nuclear power plant.

[0013] S12. Obtain the borate ion concentration in the primary loop water of a nuclear power plant;

[0014] S13. Based on the borate ion concentration in the primary loop water of the nuclear power plant, calculate the target lithium ion concentration C1 in the primary loop water of the nuclear power plant from the boron-lithium coordination diagram of the primary loop water of the nuclear power plant.

[0015] The boron-lithium coordination diagram in the primary loop water of a nuclear power plant pre-sets the maximum expected lithium ion concentration curve, the minimum expected lithium ion concentration curve, and the expected median of lithium ion concentration corresponding to different borate ion concentrations in the primary loop water of the nuclear power plant.

[0016] The target lithium-ion concentration C1 in the primary loop water of a nuclear power plant is the expected midline value of the lithium-ion concentration corresponding to the borate ion concentration in the primary loop water of the nuclear power plant, as shown in the boron-lithium coordination diagram.

[0017] As one feasible approach, S11, constructing a boron-lithium ion coordination diagram of borate and lithium ion concentrations in the primary loop water of a nuclear power plant, including the following steps:

[0018] Under the stable pH environment required for the primary loop water of a nuclear power plant, the concentrations of borate ions and lithium ions in the primary loop water of a nuclear power plant were measured respectively.

[0019] A boron-lithium coordination diagram was drawn, with the borate ion concentration in the primary loop water of a nuclear power plant as the x-axis and the lithium ion concentration in the primary loop water of a nuclear power plant as the y-axis.

[0020] As one possible method, S12, obtaining the borate ion concentration in the primary loop water of a nuclear power plant includes the following steps:

[0021] The concentration of borate ions in the primary loop system of a nuclear power plant can be obtained by detecting or manually inputting data through the plant's digital control system (DCS) or boron concentration meter.

[0022] As one feasible method, in S3, lithium addition is performed on the primary circuit water of the nuclear power plant, including: adding hydrated lithium hydroxide to the primary circuit water of the nuclear power plant; the formula for calculating the mass of hydrated lithium hydroxide added is:

[0023]

[0024] In the formula, M is the mass of hydrated lithium hydroxide added, in kg; V is the volume of the primary circuit water in the nuclear power plant, in m³. 3 C1 represents the target lithium-ion concentration in the primary loop water of the nuclear power plant, in mg / Kg; C0 represents the actual lithium-ion concentration in the primary loop water of the nuclear power plant, in mg / Kg.

[0025] The volume V of the primary circuit water in a nuclear power plant exists under three different operating conditions: the primary circuit power operation mode, the primary circuit hot standby operation mode, and the residual heat removal system operation mode. This volume can be obtained through the nuclear power plant's digital instrumentation and control system or manually input.

[0026] As one feasible approach, in S3, lithium removal is performed on the primary circuit water of the nuclear power plant using one of the following two methods:

[0027] Method 1: Lithium removal via water exchange in the primary loop of a nuclear power plant. The formula for calculating the water exchange volume in the primary loop of a nuclear power plant is as follows:

[0028] m = V × ln(C1 - C0)

[0029] In the formula, m represents the primary loop water exchange volume of the nuclear power plant, in cubic meters (m³). 3 V represents the volume of the primary circuit water in the nuclear power plant, in cubic meters (m³). 3 C1 represents the target lithium-ion concentration in the primary loop water of the nuclear power plant, in mg / Kg; C0 represents the actual lithium-ion concentration in the primary loop water of the nuclear power plant, in mg / Kg.

[0030] Method 2: Lithium removal via lithium removal bed in the primary loop of the nuclear power plant. The formula for calculating the operating time of the lithium removal bed in the primary loop of the nuclear power plant is as follows:

[0031]

[0032] In the formula, t is the time for the lithium bed to be de-lithiated in the primary loop of the nuclear power plant, in hours (h); V is the volume of water in the primary loop of the nuclear power plant, in cubic meters (m³). 3 v represents the primary circuit water discharge flow rate of the nuclear power plant, in m³ / s. 3 / h; C1 is the target lithium-ion concentration in the primary loop water of the nuclear power plant, in mg / Kg; C0 is the actual lithium-ion concentration in the primary loop water of the nuclear power plant, in mg / Kg;

[0033] Among them, the discharge flow rate v of the primary circuit water in a nuclear power plant exists under two different operating conditions: single-orifice plate operation mode and double-orifice plate operation mode, which can be obtained through the nuclear power plant's digital instrumentation and control system or manually input.

[0034] To achieve the above objectives, in a second aspect, the present invention also provides a lithium-ion concentration control device for a primary loop system of a nuclear power plant, comprising the steps of implementing the above-described lithium-ion concentration control method for a primary loop system of a nuclear power plant, including:

[0035] The lithium-ion acquisition module is used to acquire the actual lithium-ion concentration C0 in the primary loop water of a nuclear power plant.

[0036] The lithium-ion control module is used to calculate the target lithium-ion concentration C1 in the primary loop water of the nuclear power plant; determine the relationship between the target lithium-ion concentration C1 and the actual lithium-ion concentration C0 in the primary loop water of the nuclear power plant; if the target lithium-ion concentration C1 in the primary loop water of the nuclear power plant is greater than the actual lithium-ion concentration C0, then the lithium-adding device is controlled to perform a lithium-adding operation on the primary loop water of the nuclear power plant, increasing the lithium-ion concentration in the primary loop water of the nuclear power plant; if the target lithium-ion concentration C1 in the primary loop water of the nuclear power plant is less than the actual lithium-ion concentration C0, then the lithium removal module is controlled to perform a lithium removal operation on the primary loop water of the nuclear power plant, reducing the lithium-ion concentration in the primary loop water of the nuclear power plant.

[0037] To achieve the above objectives, in a third aspect, the present invention also provides a computer device, including a memory and a processor, wherein the memory stores computer-readable instructions, and the processor executes the computer-readable instructions to implement the steps of the above-described method for controlling lithium-ion concentration in the primary loop system of a nuclear power plant.

[0038] To achieve the above objectives, in a fourth aspect, the present invention provides a computer-readable storage medium storing computer-readable instructions, which, when executed, implement the steps of the above-described method for controlling lithium-ion concentration in the primary loop system of a nuclear power plant.

[0039] Beneficial technical effects of the present invention:

[0040] The present invention relates to a method, apparatus, computer equipment, and storage medium for controlling lithium-ion concentration in the primary loop system of a nuclear power plant. By constructing a boron-lithium coordination diagram between borate ion concentration and lithium-ion concentration, it automatically calculates the target lithium-ion concentration based on real-time measured borate ion concentration. Combined with online detection of the actual lithium-ion concentration, it automatically determines and executes lithium addition or removal operations, achieving online real-time monitoring and automatic adjustment of lithium-ion concentration. Compared to existing offline manual methods for controlling lithium-ion concentration, the present invention is more convenient and efficient, while reducing the safety hazards to operators posed by highly radioactive test samples. Attached Figure Description

[0041] Figure 1This is a schematic flowchart of an embodiment of the lithium-ion concentration control method for the primary loop system of a nuclear power plant according to the present invention.

[0042] Figure 2 A schematic diagram of one embodiment of the boron-lithium coordination diagram in the primary loop water of a nuclear power plant;

[0043] Figure 3 This is a schematic diagram of one embodiment of a cation chromatography system.

[0044] In the diagram, 1: Sample module; 11: Sample tubing; 12: Filter; 13: Degassing device; 2: Lithium ion detection module; 21: Multi-port valve; 22: Eluent generator; 23: Cation chromatography column; 24: Suppressor; 25: Conductivity detector; 26: Infusion pump; 3: Lithium ion control module; 31: Raw material tank; 32: First metering pump; 33: Delivery tubing; 34: Protection device; 35: First selector valve; 36: Second selector valve; 37: Waste liquid tubing; 4: Pure water tank; 5: Online calibration sample preparation module; 51: Standard mother liquor bottle; 52: Third selector valve; 53: Second metering pump; 54: Dilution container; 6: Sample selection module. Detailed Implementation

[0045] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs; the terminology used herein in the specification of the application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.

[0046] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0047] In the description of this invention, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms according to the specific circumstances.

[0048] The terms “left,” “right,” “front,” “back,” “top,” “bottom,” etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship in which the product of the invention is usually placed during use. They are used only for the convenience of description and simplification, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the present invention.

[0049] The technical solution of the present invention will be clearly and completely described below with reference to the accompanying drawings and specific embodiments.

[0050] like Figures 1 to 3 As shown, this invention provides an embodiment of a method for controlling lithium-ion concentration in the primary loop system of a nuclear power plant. The method for controlling lithium-ion concentration in the primary loop system of a nuclear power plant according to this embodiment includes the following steps:

[0051] S1. Calculate the target lithium-ion concentration C1 in the primary loop water of a nuclear power plant;

[0052] S2. Obtain the actual lithium-ion concentration C0 in the primary loop water of the nuclear power plant;

[0053] S3. Determine the relationship between the target lithium ion concentration C1 and the actual lithium ion concentration C0 in the primary loop water of a nuclear power plant.

[0054] If the target lithium-ion concentration C1 in the primary loop water of a nuclear power plant is greater than the actual lithium-ion concentration C0, then lithium addition is performed on the primary loop water of the nuclear power plant.

[0055] If the target lithium-ion concentration C1 in the primary circuit water of a nuclear power plant is less than the actual lithium-ion concentration C0, then lithium removal operations are performed on the primary circuit water of the nuclear power plant.

[0056] In this embodiment, as one possible method, S1, calculating the target lithium ion concentration C1 in the primary loop water of the nuclear power plant includes the following steps:

[0057] S11. Construct a boron-lithium coordination relationship diagram for borate and lithium ion concentrations in the primary loop water of a nuclear power plant.

[0058] S12. Obtain the borate ion concentration in the primary loop water of the nuclear power plant by detecting it through the digital instrumentation and control system of the nuclear power plant or by boron concentration meter or by manual input.

[0059] S13. Based on the borate ion concentration in the primary loop water of the nuclear power plant, calculate the target lithium ion concentration C1 in the primary loop water of the nuclear power plant using the boron-lithium coordination diagram.

[0060] This embodiment constructs a boron-lithium ion coordination diagram for borate and lithium ion concentrations in the primary loop water of a nuclear power plant. Based on real-time measurements of the borate concentration, the target lithium ion concentration in the primary loop water can be obtained. After detecting the actual lithium ion concentration in the primary loop water, the relationship between the two concentrations is determined, and it is decided whether lithium addition or removal is necessary. Compared to current methods for controlling lithium ion concentration in the primary loop water of nuclear power plants, which involve daily offline manual sampling, testing, and offline chemical dosing adjustments, this embodiment enables online real-time monitoring and automatic adjustment of lithium ion concentration in the primary loop water. This is more convenient and efficient, while also reducing the safety hazards to operators posed by highly radioactive test samples.

[0061] In this embodiment, as one possible approach, S11, constructing a boron-lithium ion coordination diagram of borate and lithium ion concentrations in the primary loop water of a nuclear power plant includes the following steps:

[0062] Under the stable pH environment required for the primary circuit water of a nuclear power plant, the concentrations of borate ions and lithium ions in the primary circuit water of a nuclear power plant were measured respectively.

[0063] Using the borate ion concentration in the primary loop water of a nuclear power plant as the abscissa and the lithium ion concentration in the primary loop water of a nuclear power plant as the ordinate, a boron-lithium coordination diagram of borate ion concentration and lithium ion concentration in the primary loop water of a nuclear power plant is plotted. The boron-lithium coordination diagram of the primary loop water of a nuclear power plant has a pre-set maximum expected lithium ion concentration curve, minimum expected lithium ion concentration curve and expected median line corresponding to different borate ion concentrations in the primary loop water of a nuclear power plant.

[0064] The target lithium-ion concentration C1 in the primary loop water of a nuclear power plant is the expected midline value of the lithium-ion concentration corresponding to the borate ion concentration in the primary loop water of the nuclear power plant, as shown in the boron-lithium coordination diagram.

[0065] This embodiment measures the concentrations of borate and lithium ions in the primary loop water of a nuclear power plant to meet environmental requirements, and plots a boron-lithium coordination diagram showing their relationship. This provides rapid and accurate data support for subsequent adjustments to the lithium ion concentration. Figure 2 As shown in the boron-lithium coordination diagram, the optimal correspondence curve is the middle curve. The curves above and below this optimal curve are within the allowable error range, while the two outermost curves represent unacceptable boron-lithium curves. Therefore, when determining the boron-lithium corresponding concentration, the judgment should be made within the allowable error range to determine whether the lithium-ion concentration needs adjustment at the current measurement state.

[0066] In this embodiment, as a preferred method, the borate ion concentration is automatically obtained from the digital instrumentation and control system of the nuclear power plant, and the borate ion concentration is cached and updated for 1 hour. The average value of the borate ion concentration over 1 hour is calculated as the final borate ion concentration.

[0067] In this embodiment, as one possible method, in step S3, lithium addition is performed on the primary circuit water of the nuclear power plant, including: adding hydrated lithium hydroxide (LiOH·H2O) to the primary circuit water of the nuclear power plant; the formula for calculating the mass of hydrated lithium hydroxide (LiOH·H2O) added is as follows:

[0068]

[0069] In the formula, M is the mass of hydrated lithium hydroxide (LiOH·H2O) added, in kg; V is the volume of the primary circuit water in the nuclear power plant, in m³. 3 C1 represents the target lithium-ion concentration in the primary loop water of the nuclear power plant, in mg / Kg; C0 represents the actual lithium-ion concentration in the primary loop water of the nuclear power plant, in mg / Kg.

[0070] Among them, the volume V of the primary circuit water in the nuclear power plant exists under three different operating conditions: the primary circuit power operation mode, the primary circuit hot standby operation mode, and the residual heat removal system commissioning mode, which can be obtained through the nuclear power plant's digital instrumentation and control system or manually input.

[0071] In the primary loop power operation mode of a nuclear power plant, the volume V of the primary loop water is 200 m³. 3 In the primary loop hot standby operation mode of a nuclear power plant, the volume V of the primary loop water is 210 m³. 3 The waste heat removal system is in operation mode, with a primary circuit water volume V of 300 m³. 3 .

[0072] In this embodiment, as one possible approach, in step S3, one of the following two methods is used to perform lithium removal on the primary circuit water of the nuclear power plant:

[0073] Method 1: Lithium removal via water exchange in the primary loop of a nuclear power plant. The formula for calculating the water exchange volume in the primary loop of a nuclear power plant is as follows:

[0074] m = V × ln(C1 - C0)

[0075] In the formula, m represents the primary loop water exchange volume of the nuclear power plant, in cubic meters (m³). 3 V represents the volume of the primary circuit water in the nuclear power plant, in cubic meters (m³). 3 C1 represents the target lithium-ion concentration in the primary loop water of the nuclear power plant, in mg / Kg; C0 represents the actual lithium-ion concentration in the primary loop water of the nuclear power plant, in mg / Kg.

[0076] Method 2: Lithium removal via lithium removal bed in the primary loop of the nuclear power plant. The formula for calculating the operating time of the lithium removal bed in the primary loop of the nuclear power plant is as follows:

[0077]

[0078] In the formula, t is the time for the lithium bed to be de-lithiated in the primary loop of the nuclear power plant, in hours (h); V is the volume of water in the primary loop of the nuclear power plant, in cubic meters (m³). 3 v represents the primary circuit water discharge flow rate of the nuclear power plant, in m³ / s. 3 / h; C1 is the target lithium-ion concentration in the primary loop water of the nuclear power plant, in mg / Kg; C0 is the actual lithium-ion concentration in the primary loop water of the nuclear power plant, in mg / Kg;

[0079] Among them, the primary circuit water discharge flow rate v of the nuclear power plant has two different operating conditions: single orifice plate operation mode and double orifice plate operation mode, which can be obtained through the nuclear power plant's digital instrumentation and control system or manually input.

[0080] In single-orifice plate operation mode, the primary circuit water discharge flow rate v of the nuclear power plant is 13.6 m³ / s. 3 / h;

[0081] In dual-orifice plate operation mode, the primary circuit water discharge flow rate v of the nuclear power plant is 27.2 m³ / s. 3 / h.

[0082] As an implementation of the above-mentioned method for controlling lithium-ion concentration in the primary loop system of a nuclear power plant, the present invention provides an embodiment of a lithium-ion concentration control device for the primary loop system of a nuclear power plant. This device embodiment corresponds to the embodiment of the above-mentioned method for controlling lithium-ion concentration in the primary loop system of a nuclear power plant, and the device can be specifically applied to various electronic devices.

[0083] The lithium-ion concentration control device for the primary loop system of a nuclear power plant described in this embodiment includes:

[0084] The lithium-ion acquisition module is used to acquire the actual lithium-ion concentration C0 in the primary loop water of a nuclear power plant.

[0085] The lithium-ion control module 3 is used to calculate the target lithium-ion concentration C1 in the primary loop water of the nuclear power plant; determine the relationship between the target lithium-ion concentration C1 and the actual lithium-ion concentration C0 in the primary loop water of the nuclear power plant; if the target lithium-ion concentration C1 in the primary loop water of the nuclear power plant is greater than the actual lithium-ion concentration C0, then the lithium addition module is controlled to perform a lithium addition operation on the primary loop water of the nuclear power plant to increase the lithium-ion concentration in the primary loop water of the nuclear power plant; if the target lithium-ion concentration C1 in the primary loop water of the nuclear power plant is less than the actual lithium-ion concentration C0, then the lithium removal module is controlled to perform a lithium removal operation on the primary loop water of the nuclear power plant to reduce the lithium-ion concentration in the primary loop water of the nuclear power plant.

[0086] In this embodiment, as one possible approach, the actual lithium ion concentration C0 in the primary loop water of the nuclear power plant is obtained by detection using a cation chromatography system; the lithium ion acquisition module obtains the actual lithium ion concentration C0 in the primary loop water of the nuclear power plant from the cation chromatography system.

[0087] The cation chromatography system includes: a sample module 1, which includes a sample line 11 for transporting the sample to be tested; and a lithium ion detection module 2, whose first end is connected to the end of the sample line 11, for cation chromatography detection of lithium ion concentration in the primary loop water of a nuclear power plant.

[0088] The lithium addition device is used to add lithium to the sample line 11 to increase the lithium ion concentration in the primary loop water of the nuclear power plant; the lithium removal device is used to remove lithium from the sample line 11 to reduce the lithium ion concentration in the primary loop water of the nuclear power plant.

[0089] The lithium-ion detection module 2 in this embodiment employs a cation chromatography detection system, which effectively solves the problem of borate ion interference in the detection results of existing flame atomic absorption spectrometry and inductively coupled plasma atomic emission spectrometry methods, resulting in accurate detection results. Simultaneously, it can automatically add or remove lithium from the primary loop water of nuclear power plants, adjusting the lithium-ion concentration to ensure the required environmental conditions in the primary loop and improve the operational stability of the primary loop system. Compared to the current method of daily offline manual sampling, detection, and offline chemical dosing for lithium-ion concentration control, this invention enables online real-time monitoring and automatic adjustment of lithium-ion concentration in the primary loop water of nuclear power plants, making operation more convenient and efficient, while reducing the safety hazards to operators posed by highly radioactive samples.

[0090] In this embodiment, as one possible implementation method, the lithium-ion detection module 2 includes a multi-way valve 21, an eluent generator 22, a cation chromatography column 23, an inhibitor 24, a conductivity detector 25, and an infusion pump 26. The first end of the multi-way valve 21 is connected to the sample module 1 to be tested and the eluent generator 22, and the second end is connected to the cation chromatography column 23. The inhibitor 24 and the conductivity detector 25 are sequentially arranged at the end of the cation chromatography column 23. The eluent generator 22 is connected to the infusion pump 26 through a pipeline, and the inlet of the infusion pump 26 is connected to the pure water tank 4 to realize the online preparation and supply of eluent.

[0091] In this embodiment, the sample solution to be tested from the primary loop of the nuclear power plant enters the lithium ion detection module 2 through the sample pipeline 11. The eluent is automatically prepared online by the eluent generator 22, providing a continuous supply to the detection system. The sample and eluent enter the subsequent cation chromatography column 23 and suppressor 24 through different channels of the multi-port valve, and finally enter the conductivity detector 25 for detection. The chromatography column is a key component in ion chromatography analysis. According to the analytical requirements of this invention, a cation chromatography column is selected to achieve effective separation of the components in the mixture based on the different physicochemical properties of the substances to be separated. The suppressor 24 is used to remove the background conductivity of strong electrolytes in the eluent and improve the detection sensitivity. The conductivity detector 25 is used to measure the conductivity change of the eluent to obtain ion concentration information. Finally, the data processing system receives the electrical signal output by the conductivity detector 25, forms a calibration curve or chromatogram, and performs peak identification and quantitative calculation.

[0092] It should be noted that the lithium ion detection module 2 in this embodiment uses an ion chromatograph, and existing ion chromatograph equipment can be used to complete the quantitative detection of the corresponding ion concentration; the cation chromatography column 23, the suppressor 24 and the conductivity detector 25 can be obtained from the prior art, as long as ion chromatography detection is achieved.

[0093] In this embodiment, as one possible implementation method, the lithium addition device includes a raw material tank 31 and a first metering pump 32. The raw material tank 31 is filled with lithium hydroxide solution. One end of the first metering pump 32 is connected to the raw material tank 31, and the other end is connected to the sample pipeline 11.

[0094] This embodiment, by providing a lithium-adding device, can realize the automatic lithium-adding operation in the sample pipeline 11. By comparing the actual lithium-ion concentration after the sample to be tested with the target lithium-ion concentration, if the actual lithium-ion concentration is less than the target lithium-ion concentration, lithium-adding is performed; that is, the lithium hydroxide solution in the raw material tank 31 is delivered into the sample pipeline 11 through the first metering pump 32 to adjust the lithium-ion concentration.

[0095] In this embodiment, as one possible approach, a liquid level sensor is installed in the feed tank 31. By installing the liquid level sensor, the solution in the feed tank 31 can be replenished in a timely manner, ensuring the timely replenishment of lithium ions and thus ensuring timely boron-lithium coordination in the primary loop of the nuclear power plant.

[0096] In this embodiment, as one possible approach, a magnetic stirring device is provided on the raw material tank 31.

[0097] This embodiment incorporates a magnetic stirring device to stir the lithium hydroxide solution in the raw material tank 31, preventing crystallization at high concentrations from affecting lithium ion replenishment.

[0098] In this embodiment, as one possible approach, the first metering pump 32 is connected to the sample pipeline 11 via a delivery pipeline 33, and a protection device 34 is provided on the delivery pipeline 33; the protection device 34 is preferably an electromagnetic shut-off valve.

[0099] This embodiment effectively prevents samples from the primary loop of the nuclear power plant from flowing back into the automatic lithium-adding device through the delivery pipeline 33 by installing an electromagnetic shut-off valve on the delivery pipeline 33, thereby reducing the safety hazards of high-irradiation samples to operators.

[0100] In this embodiment, as one possible implementation method, the lithium adding device further includes a first selection valve 35 and a second selection valve 36. The first end of the first selection valve 35 is connected to the raw material tank 31 and the pure water tank 4 respectively, and the end is connected to the second selection valve 36 through the first metering pump 32. The end of the second selection valve 36 is connected to the conveying pipeline 33 and the waste liquid pipeline 37 respectively.

[0101] In this embodiment, by setting a first selection valve 35 and connecting it to a pure water tank 4, the first metering pump 32 and the delivery pipeline 33 can be cleaned. That is, the ultrapure water in the pure water tank 4 passes through the first selection valve 35 and the first metering pump 32 in sequence, and then flows out through the waste liquid pipeline 37 connected to the second selection valve 36, thus completing the cleaning work of this part of the pipeline and some components.

[0102] In this embodiment, the lithium addition device communicates with the host computer via PLC to obtain the dosage and control the first selection valve 35 and the first metering pump 32 to achieve automatic lithium addition. The first metering pump 32 is a rotary plunger pump with a flow rate of up to 100 mL / min, a minimum dosage of 200 μL, and a full-scale dosage deviation of <0.5%. The first selection valve 35 is a two-position three-way valve, which can automatically switch between lithium hydroxide mother liquor and pure water, and can automatically complete the dosing and cleaning work. The raw material tank 31 is a PP material storage tank, which can withstand acid and alkali corrosion and prevent impurities from precipitating.

[0103] In this embodiment, as one possible implementation method, the lithium removal device includes a pure water pipeline and a lithium removal bed; the pure water pipeline and the lithium removal bed are respectively connected to the sample pipeline 11; the lithium removal bed is preferably an ion exchange bed or an adsorption bed, which adsorbs lithium ions in the primary loop water of the nuclear power plant and reduces the lithium ion concentration in the primary loop water of the nuclear power plant to the target lithium ion concentration.

[0104] In this embodiment, as one possible approach, the lithium-adding device and the lithium-removing device are configured as movable modules.

[0105] This embodiment incorporates movable modules for both the lithium-adding and lithium-removing devices, allowing for adjustments based on the actual lithium-adding location. This adapts to the lithium-adding requirements of different pipe sections, effectively reducing the distance to the lithium-adding pipe section, minimizing the impact of dead volume, ensuring the amount of lithium ions replenished, and improving adjustment accuracy.

[0106] In this embodiment, as one possible implementation method, the cation chromatography system further includes an online calibration sample preparation module 5; the online calibration sample preparation module 5 includes a standard sample mother liquor bottle 51, a third selection valve 52, a second metering pump 53, and a dilution container 54; the first end of the third selection valve 52 is connected to the standard sample mother liquor bottle 51 and the pure water tank 4 respectively, and the last end is connected to the first end of the second metering pump 53; the last end of the second metering pump 53 is connected to the dilution container 54; the last end of the dilution container 54 and the last end of the sample pipeline 11 are both connected to the lithium ion detection module 2 through the sample selection module 6.

[0107] In this embodiment, as one possible approach, the sample selection module 6 is configured as a multi-position selection valve, which can select to enter the standard sample solution for calibration curve determination or to enter the sample solution to be tested for quantitative detection of the actual sample, thereby achieving automatic sample selection and making operation more convenient.

[0108] In this embodiment, the online calibration sample preparation module 5 is used for the continuous online preparation of standard sample solutions of different concentrations, and works with the lithium ion detection module 2 to complete the plotting of calibration curves. The sample selection module 6 is connected at one end to the online calibration sample preparation module 5 and the sample to be tested module 1, and at the other end to the lithium ion detection module 2, and is used to select calibration samples or samples to be tested. The online calibration sample preparation module 5 can also prepare the quality control samples required in the ion chromatography detection process, and work with the subsequent lithium ion detection module 2 to complete the detection work, ensuring the normal operation of the system and the accuracy of the detection results.

[0109] In this embodiment, by setting up an online calibration sample preparation module 5, the online automatic preparation of standard sample solutions used in the calibration curve can be realized. This eliminates the need for manual operation or manual assistance with preparation instruments in existing technologies for the preparation and storage of standard samples before use. This method is highly efficient, reduces storage steps, and ensures high concentration accuracy and consistency of the standard sample solutions. It avoids the adverse effects of dead volume in preparation instruments on solution concentration accuracy, ensuring high detection accuracy in subsequent tests. Specifically, pure water and mother liquor from the standard sample mother liquor bottle 51 flow through the third selection valve 52 and the second metering pump 53 respectively before entering the dilution container 54. The second metering pump 53 accurately measures and delivers a preset amount of ultrapure water and mother liquor. That is, by adding a preset volume of ultrapure water and mother liquor and mixing them evenly in the dilution container, a standard sample solution of the corresponding concentration is obtained. Multiple standard sample solutions of different concentrations can be prepared by obtaining the required volumes of ultrapure water and mother liquor according to the preset concentrations and delivering them to the dilution container for preparation. The calibration curve can be determined by preparing standard sample solutions of different concentrations online and then injecting them for testing. The operation is simple, convenient, and highly accurate.

[0110] In this embodiment, as one possible implementation, the sample module 1 to be tested further includes a filter 12 and a degassing device 13; the first end of the filter 12 is connected to the sample pipeline 11, and the last end is connected to the first end of the degassing device 13; the last end of the degassing device 13 is connected to the sample selection module 6.

[0111] This embodiment includes a filter 12 and a degassing device 13 before sample injection and detection to pre-treat the sample, removing particulate impurities and air bubbles. This effectively prevents contamination, reduces the impact of potential impurities on the detection results, and protects the subsequent lithium-ion detection module 2, enabling online sample analysis and accurate detection. Specifically, the sample enters the filter 12 through the sample pipeline 11, removing particulate matter, suspended solids, and other impurities that may interfere with the analysis results or damage the chromatographic system, ensuring sample purity and improving the accuracy and sensitivity of the analysis. The sample solution flowing out of the filter 12 enters the degassing device 13 to remove dissolved gases and eliminate air bubble interference, maintaining a stable flow rate and pressure during transport to ensure the accuracy of ion chromatography analysis and the normal operation of the instrument.

[0112] It should be noted that the filter 12 and degassing device 13 in this embodiment can be obtained from the prior art; wherein the filter 12 is a commonly used needle sample filter, microporous filter membrane or pretreatment column and other filtration device, and the degassing device 13 is a commonly used vacuum degassing, membrane degassing or heating degassing and other online degassing device.

[0113] As an implementation of the above-mentioned method for controlling lithium-ion concentration in the primary loop system of a nuclear power plant, the present invention provides an embodiment of a computer device, which corresponds to the embodiment of the above-mentioned method for controlling lithium-ion concentration in the primary loop system of a nuclear power plant.

[0114] The computer device described in this embodiment includes a memory and a processor. The memory stores computer-readable instructions, and when the processor executes the computer-readable instructions, it implements the steps of the lithium-ion concentration control method for the primary loop system of a nuclear power plant described above.

[0115] As an implementation of the above-mentioned method for controlling lithium-ion concentration in the primary loop system of a nuclear power plant, the present invention provides an embodiment of a computer-readable storage medium, which corresponds to the embodiment of the above-mentioned method for controlling lithium-ion concentration in the primary loop system of a nuclear power plant.

[0116] The computer-readable storage medium described in this embodiment stores computer-readable instructions that can be executed by at least one processor to cause the at least one processor to perform the steps of the lithium-ion concentration control method for the primary loop system of a nuclear power plant as described above.

[0117] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention. Therefore, the scope of protection of this patent should be determined by the appended claims.

Claims

1. A method for controlling lithium-ion concentration in the primary loop system of a nuclear power plant, characterized in that, Includes the following steps: S1. Calculate the target lithium-ion concentration C1 in the primary loop water of a nuclear power plant; S2. Obtain the actual lithium-ion concentration C0 in the primary loop water of the nuclear power plant; S3. Determine the relationship between the target lithium ion concentration C1 and the actual lithium ion concentration C0 in the primary loop water of a nuclear power plant. If the target lithium-ion concentration C1 in the primary loop water of a nuclear power plant is greater than the actual lithium-ion concentration C0, then lithium addition is performed on the primary loop water of the nuclear power plant. If the target lithium-ion concentration C1 in the primary circuit water of a nuclear power plant is less than the actual lithium-ion concentration C0, then lithium removal operations are performed on the primary circuit water of the nuclear power plant.

2. The lithium-ion concentration control method for the primary loop system of a nuclear power plant according to claim 1, characterized in that, S1, Calculate the target lithium-ion concentration C1 in the primary loop water of the nuclear power plant, including the following steps: S11. Construct a boron-lithium coordination relationship diagram for borate and lithium ion concentrations in the primary loop water of a nuclear power plant. S12. Obtain the borate ion concentration in the primary loop water of a nuclear power plant; S13. Based on the borate ion concentration in the primary loop water of the nuclear power plant, calculate the target lithium ion concentration C1 in the primary loop water of the nuclear power plant using the boron-lithium coordination diagram.

3. The lithium-ion concentration control method for the primary loop system of a nuclear power plant according to claim 2, characterized in that, The boron-lithium coordination diagram in the primary loop water of a nuclear power plant pre-sets the maximum expected lithium ion concentration curve, the minimum expected lithium ion concentration curve, and the expected median of lithium ion concentration corresponding to different borate ion concentrations in the primary loop water of the nuclear power plant. The target lithium-ion concentration C1 in the primary loop water of a nuclear power plant is the expected midline value of the lithium-ion concentration corresponding to the borate ion concentration in the primary loop water of the nuclear power plant, as shown in the boron-lithium coordination diagram.

4. The lithium-ion concentration control method for the primary loop system of a nuclear power plant according to claim 2, characterized in that, S11, Construct a boron-lithium ion coordination diagram for borate and lithium ion concentrations in the primary loop water of a nuclear power plant, including the following steps: Under the stable pH environment required for the primary circuit water of a nuclear power plant, the concentrations of borate ions and lithium ions in the primary circuit water of a nuclear power plant were measured respectively. A boron-lithium coordination diagram was drawn, with the borate ion concentration in the primary loop water of a nuclear power plant as the x-axis and the lithium ion concentration in the primary loop water of a nuclear power plant as the y-axis.

5. The method for controlling lithium-ion concentration in the primary loop system of a nuclear power plant according to claim 2, characterized in that, S12, Obtaining the borate ion concentration in the primary loop water of a nuclear power plant, includes the following steps: The concentration of borate ions in the primary loop system of a nuclear power plant can be obtained through digital instrumentation and control systems, boron concentration meters, or manual input.

6. The method for controlling lithium-ion concentration in the primary loop system of a nuclear power plant according to claim 1, characterized in that, In S3, the lithium addition operation for the primary circuit water of the nuclear power plant includes: adding hydrated lithium hydroxide to the primary circuit water; the formula for calculating the mass of hydrated lithium hydroxide added is: In the formula, M is the mass of hydrated lithium hydroxide added, in kg; V is the volume of the primary circuit water in the nuclear power plant, in m³. 3 C1 represents the target lithium-ion concentration in the primary loop water of the nuclear power plant, in mg / Kg; C0 represents the actual lithium-ion concentration in the primary loop water of the nuclear power plant, in mg / Kg. The volume V of the primary circuit water in a nuclear power plant exists under three different operating conditions: the primary circuit power operation mode, the primary circuit hot standby operation mode, and the residual heat removal system commissioning mode. This volume can be obtained through the nuclear power plant's digital instrumentation and control system or manually input.

7. The method for controlling lithium-ion concentration in the primary loop system of a nuclear power plant according to claim 1, characterized in that, In S3, lithium removal is performed on the primary circuit water of the nuclear power plant using one of the following two methods: Method 1: Lithium removal via water exchange in the primary loop of a nuclear power plant. The formula for calculating the water exchange volume in the primary loop of a nuclear power plant is as follows: m = V × ln(C1 - C0) In the formula, m represents the primary loop water exchange volume of the nuclear power plant, in cubic meters (m³). 3 V represents the volume of the primary circuit water in the nuclear power plant, in cubic meters (m³). 3 C1 represents the target lithium-ion concentration in the primary loop water of the nuclear power plant, in mg / Kg; C0 represents the actual lithium-ion concentration in the primary loop water of the nuclear power plant, in mg / Kg. Method 2: Lithium removal via lithium removal bed in the primary loop of the nuclear power plant. The formula for calculating the operating time of the lithium removal bed in the primary loop of the nuclear power plant is as follows: In the formula, t is the time for the lithium bed to be de-lithiated in the primary loop of the nuclear power plant, in hours (h); V is the volume of water in the primary loop of the nuclear power plant, in cubic meters (m³). 3 v represents the primary circuit water discharge flow rate of the nuclear power plant, in m³ / s. 3 / h; C1 is the target lithium-ion concentration in the primary loop water of the nuclear power plant, in mg / Kg; C0 is the actual lithium-ion concentration in the primary loop water of the nuclear power plant, in mg / Kg; Among them, the discharge flow rate v of the primary circuit water in a nuclear power plant exists under two different operating conditions: single-orifice plate operation mode and double-orifice plate operation mode, which can be obtained through the nuclear power plant's digital instrumentation and control system or manually input.

8. A lithium-ion concentration control device for the primary loop system of a nuclear power plant, characterized in that, include: The lithium-ion acquisition module is used to acquire the actual lithium-ion concentration C0 in the primary loop water of a nuclear power plant. The lithium-ion control module is used to calculate the target lithium-ion concentration C1 in the primary loop water of the nuclear power plant; determine the relationship between the target lithium-ion concentration C1 and the actual lithium-ion concentration C0 in the primary loop water of the nuclear power plant; if the target lithium-ion concentration C1 in the primary loop water of the nuclear power plant is greater than the actual lithium-ion concentration C0, then the lithium-adding device is controlled to perform a lithium-adding operation on the primary loop water of the nuclear power plant, increasing the lithium-ion concentration in the primary loop water of the nuclear power plant; if the target lithium-ion concentration C1 in the primary loop water of the nuclear power plant is less than the actual lithium-ion concentration C0, then the lithium removal module is controlled to perform a lithium removal operation on the primary loop water of the nuclear power plant, reducing the lithium-ion concentration in the primary loop water of the nuclear power plant.

9. A computer device comprising a memory and a processor, wherein the memory stores computer-readable instructions, characterized in that, When the processor executes the computer-readable instructions, it implements the steps of the lithium-ion concentration control method for the primary loop system of a nuclear power plant as described in any one of claims 1-7.

10. A computer-readable storage medium storing computer-readable instructions thereon, characterized in that, When the computer-readable instructions are executed, they implement the steps of the lithium-ion concentration control method for the primary loop system of a nuclear power plant as described in any one of claims 1-7.

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