Double-loop hydrochemistry multi-parameter cooperative regulation and control test device for nuclear power material corrosion simulation

Abstract

The invention discloses a double-loop water chemical multi-parameter coordinated regulation and control test device for nuclear power material corrosion simulation. The double-loop water chemical multi-parameter coordinated regulation and control test device comprises a low-pressure water chemical pretreatment loop, a high-temperature and high-pressure corrosion simulation loop and a control module, the low-pressure water chemical pretreatment loop is connected with the high-temperature and high-pressure corrosion simulation loop through a pipeline and a valve, so that the test medium regulated and controlled by the low-pressure water chemical pretreatment loop is conveyed to the high-temperature and high-pressure corrosion simulation loop and flows back to the low-pressure water chemical pretreatment loop; the control module is electrically connected with the first monitoring component, the second monitoring component, the dissolved hydrogen / oxygen control unit, the dosing unit and the autoclave heating unit, receives and analyzes the hydrochemical parameter deviation of the low-pressure hydrochemical pretreatment loop and the high-temperature and high-pressure corrosion simulation loop by adopting a PID (Proportion Integration Differentiation) regulation algorithm, and dynamically regulates the working state of the execution unit; therefore, multi-parameter coordinated regulation and control are realized.

Description

A dual-loop water chemistry multi-parameter synergistic control experimental device for simulating corrosion of nuclear power materials Technical Field

[0001] This invention relates to the field of nuclear power technology, and more specifically to a dual-loop water chemistry multi-parameter synergistic control experimental device for simulating corrosion of nuclear power materials. Background Technology

[0002] Current research on the corrosion behavior of metallic materials used in nuclear power plants primarily employs operational condition simulation and water chemistry control techniques. These techniques include both closed-loop simulations and single-reactor simulations. All simulations utilize high-pressure reactors and heaters to create operating conditions exceeding 300°C and 10 MPa. For water chemistry control, water purification is achieved using ion exchange columns, and reagents are added manually or via pumps. Water chemistry parameters are primarily monitored using sensors such as pH meters, dissolved oxygen probes, and conductivity probes.

[0003] For the preparation of simulated contamination samples from the primary loop of nuclear power plants, current methods include coating, room-temperature simulated deposition, electrodeposition, and chemical precipitation with heat treatment synthesis. In addition, this patent employs a method that simulates real-world operating conditions. The closer the simulated contamination sample is to real-world conditions, the more representative it will be.

[0004] Currently, most decontamination technology development for nuclear power plant primary loop system equipment is conducted in laboratory environments, using sample testing, or on-site cold or hot testing. There is a lack of equipment capable of conducting experimental development of nuclear power plant primary loop decontamination processes.

[0005] In existing technologies, automation is mostly partial adjustment, lacking full-process intelligent integration, and relies heavily on manual switching of chemical dosing steps. Furthermore, each automation module (monitoring, dosing, heating) operates independently without a unified control platform, resulting in cumbersome operation and potential parameter lag. Some existing technologies feature multiple types of experimental sections or detachable components, but lack multi-functional integrated design. For example, sample holders are only compatible with fuel elements and cannot simultaneously test sheet and tubular samples; the lack of dedicated cleaning structures means that residual corrosion products in the pipelines after testing can easily interfere with subsequent experiments, limiting the practicality of the structure. The fragmented functions of existing technologies limit their application to research on corrosion behavior in the primary loop of nuclear power plants, making it impossible to prepare simulated contamination samples or conduct experiments for decontamination process development. Summary of the Invention

[0006] To achieve the above and other related objectives, this invention discloses a dual-loop water chemistry multi-parameter synergistic control experimental device for simulating corrosion of nuclear power materials, comprising a low-pressure water chemistry pretreatment loop, a high-temperature and high-pressure corrosion simulation loop, and a control module; the low-pressure water chemistry pretreatment loop and the high-temperature and high-pressure corrosion simulation loop are connected via pipelines and valves, so that the test medium regulated by the low-pressure water chemistry pretreatment loop is transported to the high-temperature and high-pressure corrosion simulation loop and then returned to the low-pressure water chemistry pretreatment loop; wherein, the low-pressure water chemistry pretreatment loop includes a water storage tank, a circulation pump, a first monitoring component, an ion exchange unit, and other components connected in sequence. The system includes a dissolved hydrogen / oxygen control unit, a dosing unit, and a water supply pump, and is equipped with a safety valve and a shut-off valve. The high-temperature and high-pressure corrosion simulation circuit includes a high-pressure pump, a pulsation damper, an electrical contact pressure gauge, a preheater, a heat exchanger, a high-pressure vessel, a two-stage cooling unit, and a second monitoring component connected in sequence. The control module is electrically connected to the first monitoring component, the second monitoring component, the dissolved hydrogen / oxygen control unit, the dosing unit, and the high-pressure vessel heating unit. It uses a PID control algorithm to receive and analyze the deviations in water chemical parameters between the low-pressure water chemical pretreatment circuit and the high-temperature and high-pressure corrosion simulation circuit, and dynamically adjusts the working state of the execution unit to achieve multi-parameter coordinated control.

[0007] Preferably, the first monitoring component includes a dissolved oxygen sensor, a dissolved hydrogen sensor, a pH meter, and a conductivity meter, used to collect data on the dissolved oxygen concentration, dissolved hydrogen concentration, pH value, and conductivity of the circulating water in real time.

[0008] Preferably, the first monitoring component is configured as a multi-branch parallel structure: it includes at least a first branch for measuring conductivity, a second branch for measuring pH, a third branch for measuring dissolved hydrogen, and a fourth branch for measuring dissolved oxygen. Each branch is equipped with a shut-off valve, a flow meter, and a corresponding sensor / instrument, and is electrically connected to the control module.

[0009] Preferably, the ion exchange unit includes an activated carbon column and a mixed bed ultrapure column connected in series. The activated carbon column is used to adsorb impurity particles in the water, and the mixed bed ultrapure column is used to exchange anions and cations in the water into hydrogen ions and hydroxide ions to reduce conductivity.

[0010] Preferably, the dissolved hydrogen / oxygen control unit includes parallel hydrogen and oxygen removal pathways, oxygen control pathways, and hydrogen control pathways, and the amount of injected gas is controlled by a gas mass flow controller for each pathway.

[0011] Preferably, the dosing unit includes multiple parallel dosing branches, each of which includes a dosing bottle and a peristaltic pump. The peristaltic pump is connected to a water storage tank and electrically connected to a control module to adjust the medium by adding acid, alkali and / or detergent.

[0012] Preferably, the autoclave adopts a split heating structure and the heating power can be adjusted by the control module. The autoclave lid is equipped with a sapphire window. The autoclave is equipped with a detachable sample rack. The sample rack is made of nuclear-grade stainless steel and can fix multiple nuclear power material samples at the same time. The spacing between the sample fixing positions is adjustable.

[0013] Preferably, the test apparatus further includes a flushing circuit, which includes a flushing water tank, a flushing pump, and pipeline valves. The flushing pump has an overpressure protection function and automatically stops after the output pressure exceeds the limit. The flushing circuit is connected to a low-pressure water chemical pretreatment circuit and a high-temperature and high-pressure corrosion simulation circuit, respectively, to perform cleaning before the start of the test and / or after the end of the test.

[0014] By adopting the above technical solution, the low-pressure water chemical pretreatment loop and the high-temperature and high-pressure corrosion simulation loop are linked. The control module collects, analyzes deviations, and dynamically adjusts the key water chemical parameters of the two loops in real time. This allows the test medium to be purified, dissolved hydrogen / oxygen regulated, and pre-conditioned with chemicals before entering the corrosion simulation section. This results in a more stable and repeatable construction of the water chemical environment related to nuclear power material service and supports corrosion simulation and simulated decontamination tests. At the same time, the high-temperature and high-pressure loop is equipped with pressure stabilization and safety protection, cooling and online monitoring units. Combined with an adjustable-heated autoclave, viewing window, and detachable multi-sample holder, the observability and ease of operation of the test process are improved. In addition, the flushing loop is used to clean key pipelines before and after the test, reducing residues and cross-influence. With data storage and trend curve output, the test process can be traced and recorded, reducing the uncertainty caused by traditional manual adjustment. Attached Figure Description

[0015] The above and other features, advantages, and aspects of the embodiments of this disclosure will become more apparent from the accompanying drawings and the following detailed description. The drawings are provided for a better understanding of the invention and are not intended to limit the scope of this disclosure. In the drawings, the same or similar reference numerals denote the same or similar elements, wherein: FIG1 is a schematic diagram of an embodiment of the present invention.

[0016] Reference numerals: 1. Water storage tank; 21. First circulation pump; 22. Second circulation pump; 23. Third circulation pump; 3. Conductivity meter; 4. pH meter; 5. Dissolved oxygen sensor; 6. Dissolved hydrogen sensor; 7. Activated carbon column; 8. Mixed bed ultrapure column; 91. First flow meter; 92. Second flow meter; 93. Third flow meter; 94. Fourth flow meter; 95. Fifth flow meter; 101. First gas cylinder; 102. Second gas cylinder; 103. Third gas cylinder; 111. First mass flow controller; 112. Second mass flow controller; 113. Third mass flow controller; 121. First dosing bottle; 122. Second dosing bottle; 123. Third dosing bottle; 124. Fourth dosing bottle; 131. First peristaltic pump; 132. Second peristaltic pump; 133. Third peristaltic pump; 134. Fourth peristaltic pump; 14. Peristaltic pump; 15. Autoclave; 16. Heat exchanger; 17. Electrical contact pressure gauge; 18. Pulsation damper; 191. High-pressure pump; 192. First back pressure valve; 201. Second back pressure valve; 202. First cooler; 211. Second pressure gauge; 212. Second pressure gauge; 221. First shut-off valve; 222. Second shut-off valve; 223. Third shut-off valve; 224. Fourth shut-off valve; 225. Fifth shut-off valve; 226. Sixth shut-off valve; 227. Seventh shut-off valve; 228. Eighth shut-off valve; 229. Ninth shut-off valve; 2210. Tenth shut-off valve; 231. First safety valve; 232. Second safety valve; 24. Ultraviolet sterilization module; 251. First temperature sensor; 252. Second temperature sensor; 26. Control module; 27. Rinse water tank. Detailed Implementation

[0017] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0018] Referring to Figure 1, an embodiment of the present invention provides a dual-loop water chemistry multi-parameter coordinated control experimental device for simulating corrosion of nuclear power materials, including a low-pressure water chemistry pretreatment loop, a high-temperature and high-pressure corrosion simulation loop, and a control module 26.

[0019] The low-pressure water chemical pretreatment circuit is connected to the high-temperature and high-pressure corrosion simulation circuit through pipelines and valves, so that the test medium regulated by the low-pressure water chemical pretreatment circuit is transported to the high-temperature and high-pressure corrosion simulation circuit and then returned to the low-pressure water chemical pretreatment circuit; wherein, the low-pressure water chemical pretreatment circuit includes a water storage tank 1, a circulation pump, a first monitoring component, an ion exchange unit, a dissolved hydrogen / oxygen control unit, a dosing unit and a water replenishment pump connected in sequence, and is equipped with a safety valve and a shut-off valve.

[0020] The high-temperature and high-pressure corrosion simulation circuit includes a high-pressure pump 18, a pulsation damper 17, an electrical contact pressure gauge 16, a preheater, a heat exchanger, an autoclave 14, a two-stage cooling unit, and a second monitoring component connected in sequence.

[0021] The control module 26 is electrically connected to the first monitoring component, the second monitoring component, the dissolved hydrogen / oxygen control unit, the dosing unit, and the heating unit of the autoclave 14. It uses an AI-optimized PID control algorithm to receive and analyze the deviations of water chemical parameters in the low-pressure water chemical pretreatment loop and the high-temperature and high-pressure corrosion simulation loop, and dynamically adjusts the working state of the execution unit to achieve multi-parameter coordinated control.

[0022] Preferably, the first monitoring component includes a dissolved oxygen sensor 5, a dissolved hydrogen sensor 6, a pH meter 4, and a conductivity meter, used to collect data on dissolved oxygen concentration, dissolved hydrogen concentration, pH value, and conductivity of circulating water in real time.

[0023] Preferably, the first monitoring component is configured as a multi-branch parallel structure: it includes at least a first branch for measuring conductivity, a second branch for measuring pH, a third branch for measuring dissolved hydrogen, and a fourth branch for measuring dissolved oxygen. Each branch is equipped with a shut-off valve, a flow meter, and a corresponding sensor / instrument, and is electrically connected to the control module 26.

[0024] Preferably, the ion exchange unit includes an activated carbon column 7 and a mixed bed ultrapure column 8 connected in series. The activated carbon column 7 is used to adsorb impurity particles in the water, and the mixed bed ultrapure column 8 is used to exchange anions and cations in the water into hydrogen ions and hydroxide ions to reduce conductivity.

[0025] Preferably, the dissolved hydrogen / oxygen control unit includes parallel hydrogen and oxygen removal pathways, oxygen control pathways, and hydrogen control pathways, and the amount of injected gas is controlled by a gas mass flow controller for each pathway.

[0026] Preferably, the dosing unit includes multiple parallel dosing branches, each of which includes a dosing bottle and a peristaltic pump. The peristaltic pump is connected to the water storage tank 1 and electrically connected to the control module 26 to adjust the medium by adding acid, alkali and / or detergent.

[0027] Preferably, the autoclave 14 adopts a split heating structure and the heating power can be adjusted by the control module 26. The autoclave lid is provided with a sapphire window. The autoclave 14 is provided with a detachable sample rack. The sample rack is made of nuclear-grade stainless steel and can fix multiple nuclear power material samples at the same time. The spacing between the sample fixing positions is adjustable.

[0028] Preferably, the test apparatus further includes a flushing circuit, which includes a flushing water tank 27, a flushing pump, and pipeline valves. The flushing pump has an overpressure protection function and automatically stops after the output pressure exceeds the limit. The flushing circuit is connected to a low-pressure water chemical pretreatment circuit and a high-temperature and high-pressure corrosion simulation circuit, respectively, to perform cleaning before the start of the test and / or after the end of the test.

[0029] In a preferred embodiment of the present invention, the low-pressure water chemical pretreatment loop includes a water storage tank 1, a first circulation pump 21, a first monitoring module, an activated carbon column 7, a mixed-bed ultrapure column 8, a dissolved hydrogen / oxygen control unit, a dosing unit, an ultraviolet sterilization module 24, and a second circulation pump 22. The ion exchange unit and the dissolved hydrogen / oxygen control unit are directly connected to the water storage tank 1, and the medium in the water storage tank 1 is regulated by the control module 26.

[0030] Specifically, the water storage tank 1 is connected to the first circulation pump 21 via a pipeline, and a first shut-off valve 221 is installed on the pipeline. The first circulation pump 21 is connected to the activated carbon column 7 and the mixed-bed ultrapure column 8 via pipelines, and a sixth shut-off valve 226 is installed on the pipelines. The mixed-bed ultrapure column 8 is connected back to the water storage tank 1 via a pipeline. A second circulation pump 22 is connected to the bottom of the water storage tank 1 via a pipeline, and a tenth shut-off valve 2210 is installed thereon. A second back pressure valve 192, a second pressure gauge 212, and the first shut-off valve 221 are installed at the top of the water storage tank 1. The second pressure gauge 212 is electrically connected to the control module 26. The ultraviolet sterilization module 24 is placed inside the water storage tank 1 and is electrically connected to the control module 26.

[0031] The first circulation pump 21 is used to provide power for the medium in the low-pressure water chemical pretreatment circuit, the second circulation pump 22 is used to inject the medium into the circuit, the tenth shut-off valve 2210 is used to discharge the medium in the circuit, and the first shut-off valve 221 is used to regulate the pressure in the water storage tank 1 and to release pressure when there is overpressure.

[0032] The first monitoring module is located on both sides of the sixth shut-off valve 226 and includes four parallel branches. The first branch is sequentially equipped with a second shut-off valve 222, a first flow meter 91, and a conductivity meter 3 to measure the conductivity of the liquid in the circuit. The conductivity meter 3 is electrically connected to the control module 26 and transmits the measurement results. The second branch is sequentially equipped with a third shut-off valve 223, a second flow meter 92, and a pH meter 4 to measure the pH value of the liquid in the circuit. The pH meter 4 is electrically connected to the control module 26 and transmits the measurement results. The third branch is sequentially equipped with a fourth shut-off valve 224, a third flow meter 93, and a dissolved hydrogen sensor 6 to measure the dissolved hydrogen content in the circuit. The dissolved hydrogen sensor 6 is electrically connected to the control module 26 and transmits the measurement results. The fourth branch is sequentially equipped with a fifth shut-off valve 225, a fourth flow meter 94, and a dissolved oxygen sensor 5 to measure the dissolved oxygen content in the circuit. The dissolved oxygen sensor 5 is electrically connected to the control module 26 and transmits the measurement results.

[0033] The dissolved hydrogen / oxygen control unit comprises three parallel branches, each directly connected to the bottom of the water storage tank 1 via pipelines, injecting gas directly into the medium to regulate the content of dissolved hydrogen and dissolved oxygen. A first gas cylinder 101 containing hydrogen is connected to a first mass flow controller 111 via a pipeline to increase the dissolved hydrogen content; a second gas cylinder 102 containing oxygen is connected to a second mass flow controller 112 via a pipeline to increase the dissolved oxygen content; and a third gas cylinder 103 containing argon is connected to a third mass flow controller 113 via a pipeline for removing hydrogen and oxygen from the medium. Each mass flow controller is electrically connected to the control module 26, transmitting data and controlling the mass flow rate of each gas.

[0034] The dosing unit includes four parallel branches, including a first dosing bottle 121, a second dosing bottle 122, a third dosing bottle 123, a fourth dosing bottle 124, a first peristaltic pump 131, a second peristaltic pump 132, a third peristaltic pump 133, and a fourth peristaltic pump 134. Each branch is equipped with one dosing bottle and one peristaltic pump, which are connected by a pipeline. Each peristaltic pump is directly connected to the top of the water storage tank 1 through a pipeline and is electrically connected to the control module 26. The medium in the circuit is adjusted by adding different acids, alkalis, detergents, etc.

[0035] The high-temperature and high-pressure corrosion simulation circuit includes a high-pressure vessel 14, a heat exchanger 15, an electrical contact pressure gauge 16, a pulsation damper 17, a high-pressure pump 18, a first back pressure valve 191, a first cooler 201, a second cooler 202, a first pressure gauge 211, and a temperature sensor.

[0036] Specifically, the pressure vessel 14 is connected to the electric contact pressure gauge 16 via a pipeline. The second shut-off valve 222 is located between the pressure vessel 14 and the electric contact pressure gauge 16. The heat exchanger 15 is located on the outside of the pipeline between the pressure vessel 14 and the second shut-off valve 222. The first temperature sensor 251 is located inside the pressure vessel 14. The electric contact pressure gauge 16 and the second safety valve 232 are connected at the same location on the pipeline. The pulsation damper 17 is connected to the high-pressure pump 18 via a pipeline. The high-pressure pump 18 is connected to the water storage tank 1 via a pipeline. A seventh shut-off valve 227 is installed on the pipeline. The first back pressure valve 191 is connected to the water storage tank 1 via a pipeline. The first back pressure valve 191 is connected to the pressure vessel 14 via a pipeline. The first cooler 201 and the second cooler 202 are located on the outside of the pipeline between the pressure vessel 14 and the first back pressure valve 191. A fifth flow meter 95, a second temperature sensor 252, and a first pressure gauge 211 are installed on the pipeline in sequence.

[0037] Among them, the high-pressure pump 18 is used to provide pressure in the high-pressure vessel 14, the electric contact pressure gauge 16 and the second safety valve 232 are used to monitor the pipeline pressure and release pressure to ensure safety when overpressure occurs, the pulsation damper 17 is used to stabilize the pressure, and the first back pressure valve 191 is used to control and regulate the pressure inside the vessel.

[0038] The autoclave 14 adopts a split heating structure, and the heating power can be adjusted by the control module 26. The autoclave lid is equipped with a sapphire window for observing the corrosion state of the sample inside the autoclave. The autoclave 14 is equipped with a detachable sample rack. The sample rack is made of nuclear-grade stainless steel and can fix multiple nuclear power material samples at the same time. The spacing between the sample fixing positions of the sample rack can be adjusted according to the sample size.

[0039] The flushing circuit includes a flushing water tank 27, a third circulation pump 23, and a ninth shut-off valve 229. The flushing water tank 27 and the third circulation pump 23 are connected by a pipeline. The ninth shut-off valve 229 is installed on the pipeline. The third circulation pump 23 is connected to the pipeline between the high-pressure pump 18 and the electric contact pressure gauge 16 through a pipeline, which is used to pump the cleaning fluid in the flushing water tank 27 into the circuit to achieve the cleaning of the circuit.

[0040] The control module 26 adopts an AI-optimized PID control algorithm to receive the data collected by the first and second monitoring components, analyze the deviation of water chemical parameters in the two loops in real time, and dynamically adjust the working state to achieve multi-parameter coordinated control. The control module 26 includes a data storage unit and a curve plotting unit. The data storage unit is used to record the water chemical parameters, temperature, and pressure data of the two loops during the experiment. The curve plotting unit is used to generate trend curves of dissolved oxygen concentration, pH value, temperature, and pressure changing over time in real time.

[0041] The dual-loop water chemistry multi-parameter synergistic control experimental device for simulating corrosion of nuclear power materials according to the above embodiments of the present invention includes a low-pressure water chemistry pretreatment loop, a high-temperature and high-pressure corrosion simulation loop, a control module 26, and a flushing loop. The device as a whole adopts an integrated load-bearing base plate and an aluminum profile frame to build a box-type structure. The box contains a water storage tank 1, an activated carbon column 7, a mixed bed ultrapure column 8, and various pumps. The outside of the box is equipped with circulation pipelines, operating elements, and instruments. The low-pressure water chemistry pretreatment loop and the high-temperature and high-pressure corrosion simulation loop are connected by pipelines and valves. The low-pressure loop delivers the required coolant or detergent to the high-temperature and high-pressure loop through pipelines and adjusts it in real time. The return water from the high-temperature and high-pressure loop flows back to the low-pressure loop through pipelines. Corrosion products are deposited or removed in the high-temperature and high-pressure loop during the loop circulation process. The flushing loop is connected to the key nodes of other loops through branch pipelines to complete the cleaning.

[0042] It will be understood by those skilled in the art that, unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. It should also be understood that terms such as those defined in general dictionaries should be understood to have the meaning consistent with their meaning in the context of the prior art, and should not be interpreted in an idealized or overly formal sense unless specifically defined.

[0043] For the sake of simplicity, the method embodiments are described as a series of actions. However, those skilled in the art should understand that the embodiments of the present invention are not limited to the described order of actions, because according to the embodiments of the present invention, some steps can be performed in other orders or simultaneously. Furthermore, those skilled in the art should also understand that the embodiments described in the specification are preferred embodiments, and the actions involved are not necessarily essential to the embodiments of the present invention.

[0044] As can be seen from the above description of the embodiments, those skilled in the art can clearly understand that this application can be implemented by means of software plus necessary general-purpose hardware platforms. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods described in various embodiments or some parts of the embodiments of this application.

[0045] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A dual-loop water chemistry multi-parameter synergistic control experimental device for simulating corrosion of nuclear power materials, characterized in that, The system includes a low-pressure water chemical pretreatment loop, a high-temperature and high-pressure corrosion simulation loop, and a control module. The low-pressure water chemical pretreatment loop and the high-temperature and high-pressure corrosion simulation loop are connected by pipelines and valves, so that the test medium regulated by the low-pressure water chemical pretreatment loop is transported to the high-temperature and high-pressure corrosion simulation loop and then returned to the low-pressure water chemical pretreatment loop. The low-pressure water chemical pretreatment loop includes a water storage tank, a circulating pump, a first monitoring component, an ion exchange unit, a dissolved hydrogen / oxygen control unit, a dosing unit, and a makeup water pump connected in sequence, and is equipped with a safety valve and a shut-off valve. The high-temperature and high-pressure corrosion simulation loop includes a high-pressure pump, a pulsation damper, an electrical contact pressure gauge, a preheater, a heat exchanger, an autoclave, a two-stage cooling unit, and a second monitoring component connected in sequence. The control module is electrically connected to the first monitoring component, the second monitoring component, the dissolved hydrogen / oxygen control unit, the dosing unit, and the autoclave heating unit. It uses a PID control algorithm to receive and analyze the deviation of water chemical parameters between the low-pressure water chemical pretreatment loop and the high-temperature and high-pressure corrosion simulation loop and dynamically adjusts the working state of the execution unit to achieve multi-parameter coordinated control.

2. The experimental apparatus according to claim 1, characterized in that, The first monitoring component includes a dissolved oxygen sensor, a dissolved hydrogen sensor, a pH meter, and a conductivity meter, used to collect data on dissolved oxygen concentration, dissolved hydrogen concentration, pH value, and conductivity of circulating water in real time.

3. The experimental apparatus according to claim 1, characterized in that, The first monitoring component is configured as a multi-branch parallel structure: it includes at least a first branch for measuring conductivity, a second branch for measuring pH, a third branch for measuring dissolved hydrogen, and a fourth branch for measuring dissolved oxygen. Each branch is equipped with a shut-off valve, a flow meter, and a corresponding sensor / instrument, and is electrically connected to the control module.

4. The experimental apparatus according to claim 1, characterized in that, The ion exchange unit includes an activated carbon column and a mixed bed ultrapure column connected in series. The activated carbon column is used to adsorb impurity particles in the water, and the mixed bed ultrapure column is used to exchange anions and cations in the water into hydrogen ions and hydroxide ions to reduce conductivity.

5. The experimental apparatus according to claim 1, characterized in that, The dissolved hydrogen / oxygen control unit includes parallel hydrogen and oxygen removal pathways, oxygen control pathways, and hydrogen control pathways, and the amount of injected gas is controlled by a gas mass flow controller for each pathway.

6. The experimental apparatus according to claim 1, characterized in that, The dosing unit includes multiple parallel dosing branches, each of which includes a dosing bottle and a peristaltic pump. The peristaltic pump is connected to a water storage tank and electrically connected to a control module to adjust the medium by adding acid, alkali and / or detergent.

7. The experimental apparatus according to claim 1, characterized in that, The autoclave adopts a split heating structure and the heating power can be adjusted by the control module. The autoclave lid is equipped with a sapphire window. The autoclave is equipped with a detachable sample rack. The sample rack is made of nuclear-grade stainless steel and can fix multiple nuclear power material samples at the same time. The spacing between the sample fixing positions is adjustable.

8. The test apparatus according to claim 1, characterized in that, The test apparatus also includes a flushing circuit, which includes a flushing water tank, a flushing pump, and pipeline valves. The flushing pump has an overpressure protection function and automatically stops after the output pressure exceeds the limit. The flushing circuit is connected to a low-pressure water chemical pretreatment circuit and a high-temperature and high-pressure corrosion simulation circuit, respectively, to perform cleaning before the start of the test and / or after the end of the test.

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