A deaerator flushing method and apparatus

Abstract

The application belongs to the technical field of power plant thermal system, and particularly relates to a deaerator flushing method and device. The method comprises: sampling and measuring the water quality of the deaerator to obtain current water quality data; if the current water quality data is greater than preset target water quality data, determining a target liquid level height of water injection according to the current water quality data, the target water quality data and a water quantity-water quality dynamic correlation model obtained in advance; injecting water into the deaerator to the target liquid level height, draining water to a first preset liquid level, sampling and measuring the water quality of the deaerator again, updating the current water quality data; if the updated current water quality data still does not reach the standard, updating the water quantity-water quality dynamic correlation model, and repeating the flushing until the current water quality data reaches the standard. The embodiment of the application constructs a closed-loop intelligent control system based on the combination of physical mechanism and data driving, and significantly improves the control accuracy, response speed and automation level of the flushing process.

Description

Technical Field

[0001] This application belongs to the technical field of power plant thermal systems, specifically relating to a deaerator flushing method and apparatus. Background Technology

[0002] During the startup process following a nuclear power plant overhaul, flushing the feedwater system is a crucial step in ensuring that the water quality meets the chemical standards required by the World Association of Nuclear Operators (WANO). The deaerator, as a core component, directly impacts the safety and economic efficiency of subsequent thermal system operation due to its internal cleanliness. The deaerator flushing process involves the coordinated control of several key operating parameters, including the impact of liquid level changes on water flow disturbance, the effect of temperature distribution on impurity dissolution and sedimentation, and the evolution of water quality indicators as flushing water volume accumulates.

[0003] Currently, flushing operations generally adopt an experience-driven, phased flushing and drainage model, relying on chemical sampling results to determine whether to repeat flushing. This extensive management approach not only leads to redundant flushing times and high consumption of demineralized water, but also prolongs the unit start-up preparation time, thus restricting the overall operating efficiency and resource utilization level of the power plant. Summary of the Invention

[0004] The purpose of this application is to provide a deaerator flushing method and apparatus to solve the problems of redundant flushing times and large consumption of demineralized water in the prior art.

[0005] The technical solution to achieve the purpose of this application is as follows: The first aspect of this application provides a deaerator flushing method, the method comprising: Step S101: After filling the deaerator with water to the first preset liquid level, the water quality of the deaerator is sampled and measured to obtain the current water quality data; Step S102: If the current water quality data is greater than the preset target water quality data, then determine the target liquid level height for water injection based on the current water quality data, the target water quality data, and the pre-obtained water quantity-water quality dynamic correlation model; Step S103: Fill the deaerator with water to the target liquid level, then drain the water to the first preset liquid level, and take water samples from the deaerator again to measure the water quality and update the current water quality data. Step S104: If the updated current water quality data is still greater than the target water quality data, then update the water quantity-water quality dynamic correlation model based on the current water quality data before the update and the updated current water quality data, and repeat steps S102-S103 until the current water quality data is not greater than the target water quality data.

[0006] Optionally, the water quantity-water quality dynamic correlation model is specifically as follows: (1) C target =C0·e -k·Q / V (1) In the formula, C target The target water quality data is defined as C0, the current water quality data is defined as k, the coefficient is Q, the required replacement water volume is Q, and the deaerator volume is V. The target liquid level height is obtained based on Q and the deaerator cross-sectional area.

[0007] Optionally, after step S104, the method further includes: Step S105: Perform a first-loop flushing of the deaerator; Step S105 specifically includes: After the deaerator liquid level is filled to the second preset level, the auxiliary water pump is started to perform a stirring operation; After stirring for a preset time, the water quality of the deaerator is sampled and measured, and the current water quality data is updated. If the updated current water quality data is still greater than the target water quality data, then the required replacement water volume and the corresponding target filling height are calculated based on the water volume-water quality dynamic correlation model, and a dynamic flushing and drainage operation is performed from the third preset liquid level to the target filling height until the current water quality data is no greater than the target water quality data.

[0008] Optionally, after step S105, the method further includes: Step S106: Perform second-loop flushing; Step S106 specifically includes: After the liquid temperature in the deaerator reaches the preset temperature range, the flushing path is switched to the "deaerator-auxiliary feed water pump-high pressure heater bypass-low pressure heater" loop, and the water quantity-water quality dynamic correlation model is used for flushing. At the same time, the standby auxiliary feed water pump is started and runs in parallel with the first pump to continuously flush the high pressure heater bypass pipeline. During the second circuit flushing process, the water quality of the deaerator is sampled and measured at preset intervals, and the cumulative flushing water volume is counted. The water volume-water quality dynamic correlation model is then corrected online using the sampled data and the cumulative flushing water volume.

[0009] Optionally, step S106 may be followed by: Step S107: Perform third-loop flushing; Step S107 specifically includes: After the second loop flushing reaches the predetermined time or the deaerator water quality stabilizes, the path will be switched to a forward flushing loop of "deaerator-auxiliary feedwater pump-high pressure heater-condenser", and flushing will be carried out using the dynamic correlation model of water quantity and water quality. During the third circuit flushing process, the water quality of the deaerator is sampled and measured at the preset intervals, and the cumulative flushing water volume is counted. The water volume-water quality dynamic correlation model is then corrected online using the sampled data and the cumulative flushing water volume.

[0010] Optionally, after step S107, the method further includes: Step S108: Perform the fourth circuit flush; Step S108 specifically includes: Open the inlet valve of the main feed water pump and use the pressure head of the deaerator to slowly fill the main feed water pump and its outlet pipeline to warm up the pipes and vent air, thus completing the preparation of the main feed water system pipeline filling. After the main water pump completes its trial run, the flushing path is switched to the fourth circuit, and the system is circulated through the main water pump. During or after the flushing process, drainage is performed. During the drainage process, the temperature T of the hot waste liquid pit is continuously compared. sump With safety control threshold T control ; When T sump Less than T control Keep the drain valve open and continue draining; When Tsump is greater than or equal to T control At this time, close the drain valve to stop the discharge of high-temperature water; simultaneously open the cold water supply valve to add cold water into the hot waste liquid pit for mixing and cooling until T sump Less than T control ; Obtain the latest updated current water quality data; If the current water quality data is not greater than the target water quality data, then end the drainage process.

[0011] Optionally, the step of obtaining the latest updated current water quality data further includes: If the current water quality data is greater than the target water quality data, the deaerator level will be refilled to the second preset level, and the auxiliary water pump will be started for recirculation to maintain water flow disturbance. Take another water sample from the deaerator and update the current water quality data; If the current water quality data is still greater than the target water quality data, the replacement water volume is determined according to the water quantity-water quality dynamic correlation model, and a dynamic flushing and drainage operation is performed.

[0012] Optionally, step S108 may be preceded by: Keep the deaerator liquid level within the preset liquid level range; The water temperature in the deaerator is raised to the preset temperature range by using the reboiling steam regulating valve.

[0013] A second aspect of this application provides a deaerator flushing device, the device comprising: The sampling and measurement module is used to sample and measure the water quality of the deaerator after water is injected into the deaerator to the first preset liquid level, and to obtain the current water quality data. The liquid level determination module is used to determine the target liquid level height for water injection based on the current water quality data, the target water quality data, and a pre-obtained water quantity-water quality dynamic correlation model when the current water quality data is greater than the preset target water quality data. The flushing control module is used to inject water into the deaerator to the target liquid level height, then drain the water to the first preset liquid level, and then sample and measure the water quality of the deaerator again to update the current water quality data. The model update module is used to update the water quantity-water quality dynamic correlation model based on the current water quality data before and after the update when the updated current water quality data is still greater than the target water quality data. This process repeatedly triggers the liquid level determination module and the flushing control module until the current water quality data is no greater than the target water quality data.

[0014] The third aspect of this application provides a computer-readable storage medium having computer program code stored thereon, which, when executed, implements any one of the deaerator flushing methods provided in the first aspect of this application.

[0015] A fourth aspect of this application provides a controller, including a memory and a processor, wherein the memory stores computer program code, and when the computer program code is executed by the processor, it implements any one of the deaerator flushing methods provided in the first aspect of this application.

[0016] The beneficial technical effects of this application are as follows: This application provides a deaerator flushing method and system. The method includes: Step S101: After injecting water into the deaerator to a first preset liquid level, sampling and measuring the water quality of the deaerator to obtain current water quality data; Step S102: If the current water quality data is greater than a preset target water quality data, then determining the target liquid level height for water injection based on the current water quality data, the target water quality data, and a pre-obtained water quantity-water quality dynamic correlation model; Step S103: Injecting water into the deaerator to the target liquid level height, then draining water to the first preset liquid level, sampling and measuring the water quality of the deaerator again, and updating the current water quality data; Step S104: If the updated current water quality data is still greater than the target water quality data, then updating the water quantity-water quality dynamic correlation model based on the current water quality data before and after the update, and repeating steps S102-S103 until the current water quality data is not greater than the target water quality data. The embodiments of this application can sense, intelligently analyze and dynamically control key process parameters such as temperature, liquid level and water quality in real time during the rinsing process. Compared with the traditional reliance on human experience, it constructs a closed-loop intelligent control system based on physical mechanism and data-driven approach, which significantly improves the control accuracy, response speed and automation level of the rinsing process. Attached Figure Description

[0017] Figure 1 This is a schematic flowchart of a deaerator flushing method provided in an embodiment of this application. Detailed Implementation

[0018] To enable those skilled in the art to better understand this application, the technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described below are only a part of the embodiments of this application, and not all of them. Based on the embodiments described in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0019] The inventors of this application discovered in their research that, while existing technologies have introduced a phased cyclic rinsing process during deaerator rinsing, they still fail to incorporate temperature and liquid level as active control variables into the rinsing decision-making logic, nor have they established a dynamic filling and draining strategy based on real-time water quality feedback. For example, during the auxiliary pump turbulence or reboiling heating stage, the liquid level setpoint often follows a fixed procedure and fails to adaptively adjust based on the previous rinsing effect. In multi-loop switching rinsing, the sampling interval is too long, and the water volume-water quality correlation model is lacking, further weakening the accuracy and predictability of process control. Although typical solutions in existing technologies optimize the rinsing path sequence, they are still limited to an open-loop mode of "rinsing—sampling—judgment—repetition," unable to dynamically adjust operating parameters based on thermal state and water level during the rinsing process. This leads to a large number of ineffective filling and draining operations, resulting in a waste of water resources, heat energy, and manpower, and makes it difficult to scientifically predict the rinsing endpoint. Especially during critical stages such as bypass flushing of the high-pressure heater and commissioning of the main feedwater pump, the lack of a three-dimensional coordinated control mechanism for temperature, liquid level, and water quality prevents the system from calculating the required replacement water volume based on indicators such as iron ion concentration and setting the optimal filling height. This results in low flushing efficiency and uncontrollable start-up cycles. Therefore, there is an urgent need for a deaerator flushing method and system that integrates real-time monitoring, intelligent calculation, and closed-loop control to overcome the bottlenecks of existing technologies in process refinement, resource conservation, and intelligent decision-making.

[0020] To address this, this application provides a deaerator flushing method, which involves multi-stage flushing, gradually switching flushing paths, and dynamically adjusting the deaerator liquid level and temperature to ultimately achieve water quality compliance. The core of this method is establishing a dynamic correlation model between water volume and water quality, predicting the flushing endpoint based on real-time water quality monitoring data, and optimizing the flushing water volume. A temperature-compensated liquid level safety margin strategy is introduced to improve the safety and efficiency of the flushing process and reduce over-flushing.

[0021] Based on the above, in order to clearly and in detail illustrate the advantages of this application, the specific embodiments of this application will be described below in conjunction with the accompanying drawings.

[0022] See Figure 1 The figure is a schematic flowchart of a deaerator flushing method provided in an embodiment of this application.

[0023] This application provides a deaerator flushing method, including: Step S101: After filling the deaerator with water to the first preset liquid level, the water quality of the deaerator is sampled and measured to obtain the current water quality data; Step S102: If the current water quality data is greater than the preset target water quality data, then determine the target liquid level height for water injection based on the current water quality data, the target water quality data, and the pre-obtained water quantity-water quality dynamic correlation model; Step S103: Fill the deaerator with water to the target liquid level, then drain the water to the first preset liquid level, and take water samples from the deaerator again to measure the water quality and update the current water quality data. Step S104: If the updated current water quality data is still greater than the target water quality data, then update the water quantity-water quality dynamic correlation model based on the current water quality data before the update and the updated current water quality data, and repeat steps S102-S103 until the current water quality data is not greater than the target water quality data.

[0024] As an example, the initial preset liquid level can be 1.5 meters. In practice, water can be first added to the deaerator until the liquid level reaches 0.5 meters, then completely drained; subsequently, water can be added again to the 1.5-meter level, and the deaerator water quality can be sampled and measured. If the deaerator water quality does not meet the power plant safety regulations, a flushing and draining control scheme can be used to calculate the required water volume and liquid level for flushing the deaerator, and this scheme can be executed multiple times until the deaerator water quality meets the requirements.

[0025] This application's embodiments predict the rinsing endpoint based on real-time water quality monitoring data and optimize the rinsing water volume. It can perform real-time sensing, intelligent analysis, and dynamic control of key process parameters such as temperature, liquid level, and water quality during the rinsing process. Compared to traditional methods relying on human experience, this application's embodiments construct a closed-loop intelligent control system based on a combination of physical mechanisms and data-driven approaches, significantly improving the control accuracy, response speed, and automation level of the rinsing process.

[0026] In one example, the dynamic correlation model between water quantity and water quality can be specifically represented by the following formula (1): C target =C0·e -k·Q / V (1) In the formula, C target The target water quality data is defined as C0, the current water quality data is defined as k, the coefficient is Q, the required replacement water volume is Q, and the deaerator volume is V. The target liquid level height is obtained based on Q and the deaerator cross-sectional area.

[0027] For example, C0 = 500 μg / L, C target =200μg / L, deaerator volume V=200m³ 3 Based on the current water temperature, we initially set k=0.8, and substituting this into the model, we get 200=500·e. -0.8·Q / 200 The required replacement water volume Q≈114m³ is obtained by inverse solving. 3 .

[0028] Assume the deaerator cross-sectional area A = 100m² 2 Therefore, the corresponding liquid level change height is 114 / 100 = 1.14 meters. Considering the current liquid level is 1.5 meters, the target filling height H is calculated. target=1.5 + 1.14 = 2.64 meters. Adding a 5% margin, the actual controlled height H... actual =2.64×1.05≈2.77 meters.

[0029] Subsequently, the deaerator is flushed to a depth of 2.77 meters, and then the drain valve is used to drain water to a depth of 1.5 meters, completing one dynamic flushing and draining operation. After completion, another sample is taken. If the water quality is still unqualified, the model is updated with a new C0 value, and a new round of operating parameters is calculated. This cycle is repeated until the water quality meets the standards.

[0030] In practice, k can be an empirical coefficient, and its value is not constant. Instead, it is affected by the current water temperature T and the intensity of water flow disturbance (such as the operating status of the auxiliary water supply pump). The initial value can be derived from historical operating data and dynamically corrected based on real-time data during the flushing process.

[0031] In some possible implementations of the embodiments of this application, step S104 may be followed by: Step S105: Perform a first-loop flushing of the deaerator; Step S105 specifically includes: After the deaerator liquid level is filled to the second preset level, the auxiliary water pump is started to perform a stirring operation; After stirring for a preset time, the water quality of the deaerator is sampled and measured, and the current water quality data is updated. If the updated current water quality data is still greater than the target water quality data, then the required replacement water volume and the corresponding target filling height are calculated based on the water volume-water quality dynamic correlation model, and a dynamic flushing and drainage operation is performed from the third preset liquid level to the target filling height until the current water quality data is no greater than the target water quality data.

[0032] In practice, the deaerator level can be filled to 2.4 meters, and the auxiliary water pump can be started to stir the water. After stirring for 30 minutes, the water quality is sampled again. If the water quality is not up to standard, the required replacement water volume and the corresponding target filling height are calculated based on the collaborative control decision module, and a dynamic flushing and drainage operation is performed from 650mm to the target filling height. If the water quality is up to standard, when the deaerator level reaches 1500mm, the reboiling device is started to heat the deaerator and raise the temperature to 70℃-80℃.

[0033] In some possible implementations of the embodiments of this application, step S105 may be followed by: Step S106: Perform second-loop flushing; Step S106 specifically includes: After the liquid temperature in the deaerator reaches the preset temperature range, the flushing path is switched to the "deaerator-auxiliary feed water pump-high pressure heater bypass-low pressure heater" loop, and the water quantity-water quality dynamic correlation model is used for flushing. At the same time, the standby auxiliary feed water pump is started and runs in parallel with the first pump to continuously flush the high pressure heater bypass pipeline. During the second circuit flushing process, the water quality of the deaerator is sampled and measured at preset intervals, and the cumulative flushing water volume is counted. The water volume-water quality dynamic correlation model is then corrected online using the sampled data and the cumulative flushing water volume.

[0034] Understandably, once the flushing water quality of the first loop is qualified and the temperature meets the requirements, a series of valves are operated in a preset logical sequence: the deaerator body drain valve is closed, the valve leading to the high-pressure heater bypass is opened, the low-pressure heater flushing discharge valve is opened, etc., switching the flushing path to the loop of "deaerator → auxiliary feed water pump → high-pressure heater bypass → low-pressure heater".

[0035] Simultaneously, the backup auxiliary water pump is activated and operates in parallel with the first pump to provide a larger flushing flow rate for continuous flushing of the high-pressure heater bypass pipeline. During this stage, the chemical sampling interval can be set to 30 minutes. During each sampling, the data acquisition and monitoring module not only reports water quality data... It also reports the cumulative flushing water volume since the start of the phase using a flow meter. It can perform online correction of the key parameter k in the dynamic correlation model of water quantity and water quality.

[0036] In practice, estimation algorithms such as recursive least squares can be used to continuously update the estimated value of k using new data points, making it closer to the actual attenuation characteristics under the current temperature and flow rate. This process greatly accelerates the model's learning speed and improves the model's accuracy in depicting the current flushing process, thereby enabling a more accurate prediction of the remaining flushing water volume required to achieve qualified water quality.

[0037] In some possible implementations of the embodiments of this application, step S106 may be followed by: Step S107: Perform third-loop flushing; Step S107 specifically includes: After the second loop flushing reaches the predetermined time or the deaerator water quality stabilizes, the path will be switched to a forward flushing loop of "deaerator-auxiliary feedwater pump-high pressure heater-condenser", and flushing will be carried out using the dynamic correlation model of water quantity and water quality. During the third circuit flushing process, the water quality of the deaerator is sampled and measured at the preset intervals, and the cumulative flushing water volume is counted. The water volume-water quality dynamic correlation model is then corrected online using the sampled data and the cumulative flushing water volume.

[0038] Understandably, after the second loop flushing reaches the predetermined time or the water quality stabilizes, the system switches to the third loop. Specifically, this involves closing the high-pressure heater bypass valve, slowly opening the high-pressure heater inlet valve, and switching the path to a forward flushing loop of "deaerator → auxiliary feedwater pump → high-pressure heater → condenser".

[0039] This stage involves flushing critical sections of the main feedwater pipeline, which have high flow rates and long lengths. Flushing is continuous, with chemical sampling intervals maintained at 30-minute intervals. Data from the third loop is used to further enrich and refine the dynamic correlation model between water flow and water quality. Simultaneously, the water quality and temperature of the condenser hot water well are monitored to ensure that the received flushing water does not affect the condenser itself. The goal of this stage is to steadily reduce and stabilize the iron ion concentration within the main feedwater pipeline.

[0040] In some possible implementations of the embodiments of this application, step S107 may be followed by: Step S108: Perform the fourth circuit flush; Step S108 specifically includes: Open the inlet valve of the main feed water pump and use the pressure head of the deaerator to slowly fill the main feed water pump and its outlet pipeline to warm up the pipes and vent air, thus completing the preparation of the main feed water system pipeline filling. After the main water pump completes its trial run, the flushing path is switched to the fourth circuit, and the system is circulated through the main water pump. During or after the flushing process, drainage is performed. During the drainage process, the temperature T of the hot waste liquid pit is continuously compared. sump With safety control threshold T control ; When T sump Less than T control Keep the drain valve open and continue draining; When Tsump is greater than or equal to T control At this time, close the drain valve to stop the discharge of high-temperature water; simultaneously open the cold water supply valve to add cold water into the hot waste liquid pit for mixing and cooling until T sump Less than T control ; Obtain the latest updated current water quality data; If the current water quality data is not greater than the target water quality data, then end the drainage process.

[0041] It is understood that the embodiments of this application adjust the start-up liquid level threshold for deaerator reboiling heating; at the same time, combined with the drainage strategy of the deaerator to regulate the temperature of the hot waste liquid pit, the flushing operation is avoided due to excessive temperature. The above measures work together to reduce the heating time of equipment such as deaerators, significantly reduce ineffective flushing and drainage operations and demineralized water consumption, thereby improving resource utilization efficiency and reducing unit maintenance time.

[0042] In practice, after the main feedwater pump completes its trial run, the system enters the final high-flow-rate circulating flushing stage.

[0043] First, the reboiling heating power is reduced, and the deaerator water temperature is lowered to below 100°C by increasing the influent flow rate, to meet the temperature limitations of subsequent drainage to the hot wastewater pit. Then, the flushing loop switching module switches the path to the fourth loop (e.g., system-wide circulation via the main feedwater pump). Drainage is required during or after flushing. This stage of drainage control incorporates a safety coordination strategy based on the hot wastewater pit temperature.

[0044] Real-time monitoring of the temperature T in the hot waste liquid pit sump The collaborative control decision-making module sets two thresholds: the safety control threshold T. control =70℃ and upper temperature limit T max =80℃.

[0045] During the drainage process, T is continuously compared. sump With T control When T sump When the temperature is below 70℃, the actuator keeps the drain valve open for continuous drainage. When T sump When the temperature reaches ≥70℃, the module immediately issues an emergency command to close the drain valve and stop the discharge of high-temperature water. Simultaneously, the command opens the cold water (e.g., demineralized water) supply valve to add cold water to the hot waste liquid pit for mixing and cooling. The data acquisition and monitoring module continuously feeds back T... sump Until it drops below 70°C.

[0046] At this point, drainage is not immediately resumed; instead, the most recent water quality data is checked. If the water quality is acceptable, drainage can be stopped directly. If the water quality still needs improvement, a decision is made to resume drainage based on the current liquid level and temperature in the pit.

[0047] In one example, the step of obtaining the latest updated current water quality data may further include: If the current water quality data is greater than the target water quality data, the deaerator level will be refilled to the second preset level, and the auxiliary water pump will be started for recirculation to maintain water flow disturbance. Take another water sample from the deaerator and update the current water quality data; If the current water quality data is still greater than the target water quality data, the replacement water volume is determined according to the water quantity-water quality dynamic correlation model, and a dynamic flushing and drainage operation is performed.

[0048] It should be noted that during the later stages of the third circuit flushing, based on the predicted trend of the water quantity-water quality dynamic correlation model, it was determined that the pipeline water quality was close to the qualified standard. At this point, preparations were made for the subsequent flushing of the main feedwater pump.

[0049] First, the deaerator liquid level is precisely controlled between 850mm and 1200mm. This lower liquid level range is to reduce the pump's starting load and the required priming water when the main feedwater pump is started. The water temperature inside the deaerator is further increased from approximately 80℃ to 150℃-160℃ via the reboiling steam regulating valve. At this high temperature, the actuator slowly opens the main feedwater pump inlet valve, using the deaerator's pressure head to slowly fill the main feedwater pump and its outlet pipeline with high-temperature demineralized water, performing warm-up and venting, completing the pipeline filling preparation for the main feedwater system and creating the necessary thermal conditions for pump startup.

[0050] In some possible implementations of the embodiments of this application, step S108 may be preceded by: Keep the deaerator liquid level within the preset liquid level range; The water temperature in the deaerator is raised to the preset temperature range by using the reboiling steam regulating valve.

[0051] Understandably, if after step S108 drainage, the final sampling shows that the water quality still does not fully meet the extremely stringent standards (e.g., a requirement of less than 20 μg / L), then a final fine-tuning is performed.

[0052] The deaerator level is refilled to 2.4 meters, and the auxiliary feedwater pump is started for recirculation, maintaining water flow disturbance. Water quality is sampled again. If the water quality is unsatisfactory, the water volume-water quality dynamic correlation model is invoked one last time to calculate an accurate replacement water volume, and a small-scale dynamic flushing and drainage operation is performed. Since the system is now very clean, the required replacement water volume is usually small, and the operation is quick. Once the water quality is satisfactory, the deaerator and its associated systems are considered flushed successfully. All control modules are reset, valves are placed in normal standby mode, and the deaerator enters normal operating water level and temperature control mode, preparing for subsequent power plant startup.

[0053] In practical implementation, a data acquisition and monitoring unit can be used as the information acquisition unit, equipped with a high-precision liquid level measurement device with an output signal of 4–20 mA and a sampling frequency of not less than 1 Hz. Simultaneously, multiple resistance temperature sensors are arranged at the bottom, middle, and steam space of the deaerator to reduce measurement deviations caused by local temperature gradients. An online water quality analyzer is installed at the outlet of the main drain pipe and key flushing circuits. This analyzer can achieve near real-time detection of iron ion concentration based on spectroscopic or electrochemical methods, with a fastest detection cycle of 5 minutes, and uploads data to the main control system screen via Modbus TCP and other communication methods.

[0054] A collaborative control decision unit can be used as the core control unit to receive real-time operational data and generate control strategies. Internally, it constructs two interrelated computational models. The first is a dynamic correlation model of water quantity and quality, based on the principle of mass conservation, depicting the gradual decrease in water concentration as the replacement water volume increases during flushing. The second is a temperature-level coupled optimization control algorithm, based on extensive historical operating data, summarizing the collaborative constraint relationship between deaerator level and temperature at different flushing stages to determine a reasonable control range. For example, during the auxiliary feedwater pump's "turbidity" operation, heating is performed when the deaerator level is maintained at approximately 1950 mm, effectively preventing pump cavitation risks. In actual control, the level change range can be calculated based on the required replacement water volume for flushing, and judged in conjunction with water quality test results: when the water quality meets the requirements, the deaerator temperature is controlled to rise to 70℃~80℃; when the water quality does not meet the standards, the corresponding flushing operation continues.

[0055] Therefore, the algorithm optimizes the allowable starting liquid level threshold for reboiling heating to 1500 mm. This optimization directly breaks the sequential waiting relationship in the traditional process, allowing the heating operation to run in parallel with the liquid level raising process, which is calculated to save approximately 3 hours of critical path time. Based on the flushing stage instructions, the algorithm dynamically outputs the optimal liquid level and temperature setpoints for the current stage.

[0056] The actuator control unit can be used as the execution layer, responsible for translating the abstract instructions output by the collaborative control decision module into action commands for specific actuators. The output is connected to various key actuators in the deaerator system via hardwiring or fieldbus, including the inlet pneumatic regulating valve, outlet pneumatic regulating valve, reboiling steam regulating valve, and the frequency converter or contactor control loop of the auxiliary feedwater pump. The module internally encapsulates dedicated control logic for different devices. For the inlet and outlet valves, the control logic is mainly proportional-integral-derivative control based on the liquid level setpoint, with the output being the valve opening command. The control accuracy requirement is that the steady-state error of the liquid level does not exceed ±10mm. The control of the reboiling steam regulating valve is more complex, requiring decoupling and coordination between temperature and liquid level. When the deaerator liquid level meets L≥1500mm and the current temperature T is lower than the stage target temperature, the module activates the temperature control loop. This loop adopts a cascade control strategy: the outer loop is the temperature loop, calculating the required steam heat based on the temperature deviation; the inner loop is the steam flow loop, controlling the steam flow by adjusting the valve opening. Specifically, the control algorithm incorporates feedforward compensation for liquid level changes. This involves dynamically fine-tuning the opening of the steam valve based on the rate of liquid level rise, ensuring that the increase in heating power matches the increase in water tank volume. This prevents thermal stress caused by excessively rapid heating in localized areas or delays due to excessively slow heating. For the auxiliary feedwater pump, the module outputs simple start / stop commands or speed setpoints.

[0057] A flushing loop switching unit can also be used to manage the path switching of the flushing process. Deaerator flushing involves multiple loops, including flushing only the deaerator body, flushing to the low-pressure heater via a high-pressure heater bypass, and flushing to the condenser via a high-pressure heater in the forward direction. This unit receives "stage switching instructions" from the collaborative control decision module, and then sends an "open" or "close" command sequence to a series of electrically or pneumatically operated isolation valves distributed in the complex piping system according to a preset logic program. This module has strict interlocking protection logic to ensure that no media cross-contamination or pipeline pressure surges occur during the switching process. For example, before opening a new loop, it must be confirmed that the upstream water supply has been established and the downstream discharge path is unobstructed, and the on / off status feedback signals of the relevant valves must be consistent with the instructions; otherwise, the module will interrupt the switching and report a fault.

[0058] The above four units constitute a complete multi-level closed-loop control system. The data flow is from bottom to top, from the data acquisition and monitoring unit to the collaborative control decision-making unit; the control command flow is from top to bottom, from the collaborative control decision-making unit through the actuator control unit and the flushing circuit switching unit, and finally acts on the physical equipment terminal; the changes in the operating status of the equipment are fed back to the system through the data acquisition and monitoring unit to the human-machine interface, forming a closed loop.

[0059] The embodiments of this application can sense, intelligently analyze and dynamically control key process parameters such as temperature, liquid level and water quality in real time during the rinsing process. Compared with the traditional reliance on human experience, it constructs a closed-loop intelligent control system based on physical mechanism and data-driven approach, which significantly improves the control accuracy, response speed and automation level of the rinsing process.

[0060] Based on the deaerator flushing method provided in the above embodiments, this application also provides a deaerator flushing device.

[0061] This application provides a deaerator flushing device, comprising: The sampling and measurement module is used to sample and measure the water quality of the deaerator after water is injected into the deaerator to the first preset liquid level, and to obtain the current water quality data. The liquid level determination module is used to determine the target liquid level height for water injection based on the current water quality data, the target water quality data, and a pre-obtained water quantity-water quality dynamic correlation model when the current water quality data is greater than the preset target water quality data. The flushing control module is used to inject water into the deaerator to the target liquid level height, then drain the water to the first preset liquid level, and then sample and measure the water quality of the deaerator again to update the current water quality data. The model update module is used to update the water quantity-water quality dynamic correlation model based on the current water quality data before and after the update when the updated current water quality data is still greater than the target water quality data. This process repeatedly triggers the liquid level determination module and the flushing control module until the current water quality data is no greater than the target water quality data.

[0062] In one example, the dynamic correlation model between water quantity and water quality can be specifically represented by the following formula (1): C target =C0·e -k·Q / V (1) In the formula, C target The target water quality data is defined as C0, the current water quality data is defined as k, the coefficient is Q, the required replacement water volume is Q, and the deaerator volume is V. The target liquid level height is obtained based on Q and the deaerator cross-sectional area.

[0063] In some possible implementations of the embodiments of this application, the apparatus may further include: The first circuit flushing module is used to perform first circuit flushing on the deaerator; The first circuit flushing module is specifically used for: After the deaerator liquid level is filled to the second preset level, the auxiliary water pump is started to perform a stirring operation; After stirring for a preset time, the water quality of the deaerator is sampled and measured, and the current water quality data is updated. If the updated current water quality data is still greater than the target water quality data, then the required replacement water volume and the corresponding target filling height are calculated based on the water volume-water quality dynamic correlation model, and a dynamic flushing and drainage operation is performed from the third preset liquid level to the target filling height until the current water quality data is no greater than the target water quality data.

[0064] In some possible implementations of the embodiments of this application, the apparatus may further include: The second-loop flushing module is used to perform second-loop flushing. The second circuit flushing module is specifically used for: After the liquid temperature in the deaerator reaches the preset temperature range, the flushing path is switched to the "deaerator-auxiliary feed water pump-high pressure heater bypass-low pressure heater" loop, and the water quantity-water quality dynamic correlation model is used for flushing. At the same time, the standby auxiliary feed water pump is started and runs in parallel with the first pump to continuously flush the high pressure heater bypass pipeline. During the second circuit flushing process, the water quality of the deaerator is sampled and measured at preset intervals, and the cumulative flushing water volume is counted. The water volume-water quality dynamic correlation model is then corrected online using the sampled data and the cumulative flushing water volume.

[0065] In some possible implementations of the embodiments of this application, the apparatus may further include: The third-loop flushing module is used to perform third-loop flushing. The third-circuit flushing module is specifically used for: After the second loop flushing reaches the predetermined time or the deaerator water quality stabilizes, the path will be switched to a forward flushing loop of "deaerator-auxiliary feedwater pump-high pressure heater-condenser", and flushing will be carried out using the dynamic correlation model of water quantity and water quality. During the third circuit flushing process, the water quality of the deaerator is sampled and measured at the preset intervals, and the cumulative flushing water volume is counted. The water volume-water quality dynamic correlation model is then corrected online using the sampled data and the cumulative flushing water volume.

[0066] In some possible implementations of the embodiments of this application, the apparatus may further include: The fourth-loop flushing module is used to perform fourth-loop flushing. The fourth circuit flushing module is specifically used for: Open the inlet valve of the main feed water pump and use the pressure head of the deaerator to slowly fill the main feed water pump and its outlet pipeline to warm up the pipes and vent air, thus completing the preparation of the main feed water system pipeline filling. After the main water pump completes its trial run, the flushing path is switched to the fourth circuit, and the system is circulated through the main water pump. During or after the flushing process, drainage is performed. During the drainage process, the temperature T of the hot waste liquid pit is continuously compared. sump With safety control threshold T control ; When T sump Less than T control Keep the drain valve open and continue draining; When Tsump is greater than or equal to T control At this time, close the drain valve to stop the discharge of high-temperature water; simultaneously open the cold water supply valve to add cold water into the hot waste liquid pit for mixing and cooling until T sump Less than T control ; Obtain the latest updated current water quality data; If the current water quality data is not greater than the target water quality data, then end the drainage process.

[0067] In one example, the fourth-loop flushing module can also be used for: If the current water quality data is greater than the target water quality data, the deaerator level will be refilled to the second preset level, and the auxiliary water pump will be started for recirculation to maintain water flow disturbance. Take another water sample from the deaerator and update the current water quality data; If the current water quality data is still greater than the target water quality data, the replacement water volume is determined according to the water quantity-water quality dynamic correlation model, and a dynamic flushing and drainage operation is performed.

[0068] In some possible implementations of the embodiments of this application, the apparatus may further include: The liquid level control module is used to control the liquid level of the deaerator within a preset liquid level range; The temperature control module is used to raise the water temperature in the deaerator to a preset temperature range via the reboiling steam regulating valve.

[0069] The embodiments of this application can sense, intelligently analyze and dynamically control key process parameters such as temperature, liquid level and water quality in real time during the rinsing process. Compared with the traditional reliance on human experience, it constructs a closed-loop intelligent control system based on physical mechanism and data-driven approach, which significantly improves the control accuracy, response speed and automation level of the rinsing process.

[0070] Based on the deaerator flushing method and apparatus provided in the above embodiments, this application also provides a computer-readable storage medium storing computer program code thereon. When the computer program code is executed, it implements any one of the deaerator flushing methods provided in the above embodiments.

[0071] Based on the deaerator flushing method and apparatus provided in the above embodiments, this application also provides a controller, including a memory and a processor. The memory stores computer program code, and when the computer program code is executed by the processor, any one of the deaerator flushing methods provided in the above embodiments is implemented.

[0072] The present application has been described in detail above with reference to the accompanying drawings and embodiments. However, the present application is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present application. All content not described in detail in this application can be derived from existing technology.

Claims

1. A deaerator flushing method, characterized in that, The method includes: Step S101: After filling the deaerator with water to the first preset liquid level, the water quality of the deaerator is sampled and measured to obtain the current water quality data; Step S102: If the current water quality data is greater than the preset target water quality data, then determine the target liquid level height for water injection based on the current water quality data, the target water quality data, and the pre-obtained water quantity-water quality dynamic correlation model; Step S103: Fill the deaerator with water to the target liquid level, then drain the water to the first preset liquid level, and take water samples from the deaerator again to measure the water quality and update the current water quality data. Step S104: If the updated current water quality data is still greater than the target water quality data, then update the water quantity-water quality dynamic correlation model based on the current water quality data before the update and the updated current water quality data, and repeat steps S102-S103 until the current water quality data is not greater than the target water quality data.

2. The deaerator flushing method according to claim 1, characterized in that, The dynamic correlation model between water quantity and water quality is specifically as follows (1): C target =C0·e -k·Q / V (1) In the formula, C target The target water quality data is defined as C0, the current water quality data is defined as k, the coefficient is Q, the required replacement water volume is Q, and the deaerator volume is V. The target liquid level height is obtained based on Q and the deaerator cross-sectional area.

3. The deaerator flushing method according to claim 1 or 2, characterized in that, Following step S104, the following is also included: Step S105: Perform a first-loop flushing of the deaerator; Step S105 specifically includes: After the deaerator liquid level is filled to the second preset level, the auxiliary water pump is started to perform a stirring operation; After stirring for a preset time, the water quality of the deaerator is sampled and measured, and the current water quality data is updated. If the updated current water quality data is still greater than the target water quality data, then the required replacement water volume and the corresponding target filling height are calculated based on the water volume-water quality dynamic correlation model, and a dynamic flushing and drainage operation is performed from the third preset liquid level to the target filling height until the current water quality data is no greater than the target water quality data.

4. The deaerator flushing method according to claim 3, characterized in that, Following step S105, the following is also included: Step S106: Perform second-loop flushing; Step S106 specifically includes: After the liquid temperature in the deaerator reaches the preset temperature range, the flushing path is switched to the "deaerator-auxiliary feed water pump-high pressure heater bypass-low pressure heater" loop, and the water quantity-water quality dynamic correlation model is used for flushing. At the same time, the standby auxiliary feed water pump is started and runs in parallel with the first pump to continuously flush the high pressure heater bypass pipeline. During the second circuit flushing process, the water quality of the deaerator is sampled and measured at preset intervals, and the cumulative flushing water volume is counted. The water volume-water quality dynamic correlation model is then corrected online using the sampled data and the cumulative flushing water volume.

5. The deaerator flushing method according to claim 4, characterized in that, Following step S106, the following is also included: Step S107: Perform third-loop flushing; Step S107 specifically includes: After the second loop flushing reaches the predetermined time or the deaerator water quality stabilizes, the path will be switched to a forward flushing loop of "deaerator-auxiliary feedwater pump-high pressure heater-condenser", and flushing will be carried out using the dynamic correlation model of water quantity and water quality. During the third circuit flushing process, the water quality of the deaerator is sampled and measured at the preset intervals, and the cumulative flushing water volume is counted. The water volume-water quality dynamic correlation model is then corrected online using the sampled data and the cumulative flushing water volume.

6. The deaerator flushing method according to claim 5, characterized in that, Following step S107, the following is also included: Step S108: Perform the fourth circuit flush; Step S108 specifically includes: Open the inlet valve of the main feed water pump and use the pressure head of the deaerator to slowly fill the main feed water pump and its outlet pipeline to warm up the pipes and vent air, thus completing the preparation of the main feed water system pipeline filling. After the main water pump completes its trial run, the flushing path is switched to the fourth circuit, and the system is circulated through the main water pump. During or after the flushing process, drainage is performed. During the drainage process, the temperature T of the hot waste liquid pit is continuously compared. sump With safety control threshold T control ; When T sump Less than T control Keep the drain valve open and continue draining; When Tsump is greater than or equal to T control At this time, close the drain valve to stop the discharge of high-temperature water; simultaneously open the cold water supply valve to add cold water into the hot waste liquid pit for mixing and cooling until T sump Less than T control ; Obtain the latest updated current water quality data; If the current water quality data is not greater than the target water quality data, then end the drainage process.

7. The deaerator flushing method according to claim 6, characterized in that, The process of obtaining the latest updated current water quality data further includes: If the current water quality data is greater than the target water quality data, the deaerator level will be refilled to the second preset level, and the auxiliary water pump will be started for recirculation to maintain water flow disturbance. Take another water sample from the deaerator and update the current water quality data; If the current water quality data is still greater than the target water quality data, the replacement water volume is determined according to the water quantity-water quality dynamic correlation model, and a dynamic flushing and drainage operation is performed.

8. The deaerator flushing method according to claim 6, characterized in that, The preceding steps in step S108 include: Keep the deaerator liquid level within the preset liquid level range; The water temperature in the deaerator is raised to the preset temperature range by using the reboiling steam regulating valve.

9. A deaerator flushing device, characterized in that, The device includes: The sampling and measurement module is used to sample and measure the water quality of the deaerator after water is injected into the deaerator to the first preset liquid level, and to obtain the current water quality data. The liquid level determination module is used to determine the target liquid level height for water injection based on the current water quality data, the target water quality data, and a pre-obtained water quantity-water quality dynamic correlation model when the current water quality data is greater than the preset target water quality data. The flushing control module is used to inject water into the deaerator to the target liquid level height, then drain the water to the first preset liquid level, and then sample and measure the water quality of the deaerator again to update the current water quality data. The model update module is used to update the water quantity-water quality dynamic correlation model based on the current water quality data before and after the update when the updated current water quality data is still greater than the target water quality data. This process repeatedly triggers the liquid level determination module and the flushing control module until the current water quality data is no greater than the target water quality data.

10. A computer-readable storage medium, characterized in that, It stores computer program code, which, when executed, implements a deaerator flushing method as described in any one of claims 1-8.

11. A controller, characterized in that, It includes a memory and a processor, wherein the memory stores computer program code, and when the computer program code is executed by the processor, it implements a deaerator flushing method as described in any one of claims 1-8.

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