Vibration control method of high-pressure rotating film type deaerator

Abstract

The invention discloses a vibration control method of a high-pressure rotating film type deaerator, and relates to the technical field of deaerators. In the extremely hot state starting process of the unit, a heating steam valve below the rotating film pipe is closed so as to cut off supply of initial deoxidizing heating steam; a heating steam valve below the water spraying grate is opened to supply deep deoxidizing heating steam; the opening degree of a heating steam valve below the water spraying grate is adjusted, so that deep deoxidization heating steam is fully mixed with water flowing down from the water spraying grate, redundant superheated steam is prevented from entering a rotating film pipe or a condensed water pipe, and vibration of the deaerator is eliminated; by closing the rotating film pipe heating steam valve and accurately controlling the opening degree of the water spraying grate heating steam branch pipe valve, superheated steam is fundamentally prevented from entering a low-temperature water inlet pipeline or damaging thermal stratification of a water tank, and therefore vibration is successfully restrained, equipment vibration is effectively restrained, and operation safety is guaranteed.

Description

Technical Field

[0001] This invention relates to the field of deaerator technology, specifically to a vibration control method for a high-pressure rotary film deaerator. Background Technology

[0002] High-pressure rotary film deaerators are crucial auxiliary equipment in the regenerative systems of thermal power plants. Their function is to remove dissolved oxygen and other non-condensable gases from feedwater, preventing corrosion of thermal equipment and pipelines, and are essential for ensuring the safe and economical operation of the unit. During the extremely hot start-up of a steam turbine unit (typically referring to a rapid restart after a shutdown of less than 8 hours), the deaerator maintains a high pressure (approximately 0.8-0.9 MPa) and temperature (approximately 130-140 degrees Celsius). At this time, to maintain the water level, condensate with a relatively lower temperature (approximately 40 degrees Celsius) needs to be added. This significant temperature difference can easily cause severe vibrations in the deaerator body, connected pipelines, and feedwater pre-pump, becoming a prominent technical challenge affecting the rapid and safe start-up of the unit.

[0003] Currently, the industry's common solutions to the aforementioned vibration problem are controlling the makeup water volume of the high-pressure deaerator to reduce condensate flow or increasing the makeup water temperature entering the deaerator. However, these existing solutions have the following problems: reducing the makeup water volume directly delays the boiler's water supply process, thus prolonging the start-up time of the entire unit and affecting the economic response capability of peak-shaving units; in the initial stage of extremely hot startup, the low-pressure regenerative heating system often fails to operate normally, lacking an effective and continuous heat source to significantly increase the temperature of a large amount of makeup water, so increasing the makeup water temperature is difficult to meet the demand for continuous makeup water in practice. More importantly, these methods do not address the fundamental mechanism of vibration—the severe thermal shock generated when low-temperature makeup water rapidly mixes with the high-temperature internal environment of the equipment (including stored water, saturated steam, and the inner wall), and the resulting potential for local flashing, bubble formation and collapse (water hammer phenomenon). Therefore, they cannot fundamentally and completely eliminate vibration, and their effects are limited and incomplete.

[0004] To address the above problems, there is an urgent need for a vibration control method for high-pressure rotary film deaerators. Summary of the Invention

[0005] Technical problems to be solved To address the shortcomings of existing technologies, this invention provides a vibration control method for high-pressure rotary film deaerators. This method solves the problem that reducing the amount of makeup water directly delays the boiler's water supply process, thus prolonging the start-up time of the entire unit and affecting the economic response capability of peak-shaving units. Furthermore, in the initial stage of extremely hot startup, the low-pressure regenerative heating system often fails to operate normally, lacking an effective and continuous heat source to significantly increase the temperature of the large volume of makeup water. Therefore, methods that increase the makeup water temperature are practically insufficient to meet the demand for continuous makeup water supply. More importantly, these methods do not address the fundamental mechanism of vibration generation—the severe thermal shock generated when low-temperature makeup water rapidly mixes with the high-temperature internal environment of the equipment (including stored water, saturated steam, and the inner wall), and the resulting potential for localized flash evaporation, bubble formation and collapse (water hammer). Therefore, they cannot fundamentally and completely eliminate vibration, resulting in limited and incomplete effectiveness.

[0006] Technical solution To achieve the above objectives, the present invention provides the following technical solution: a vibration control method for a high-pressure swirl film deaerator, wherein the high-pressure swirl film deaerator structure includes a deaerator shell, inside which, from bottom to top, are arranged heat storage packing, a water spray grate, and a swirl film tube; the bottom of the deaerator shell is connected to a feed water tank via a drain pipe; a condensate pipe is connected to the deaerator shell, the condensate pipe is connected to the deaerator shell and connected to the inlet water chamber of the swirl film tube, for conveying main condensate; the steam chamber of the deaerator shell is connected to four sections of extraction steam pipe, which serve as the main heating steam source; the mother of the four sections of extraction steam pipe... The pipe is equipped with a steam branch valve for heating the water spray grate, used to control the steam flowing to the steam chamber below the water spray grate; an independent steam interface is located on the deaerator shell below the swirl film tube, connected to the main pipe of the four-section extraction steam pipe via the swirl film tube heating branch pipe; a swirl film tube heating steam valve is installed on the swirl film tube heating branch pipe, used to control the heating steam flowing to the swirl film tube area; a condensate shut-off valve is installed on the condensate pipe, and a makeup water pipe is connected to the end of the condensate pipe, the makeup water source of the makeup water pipe including at least one of: low-pressure deaerator outlet water and unit condensate makeup water; the vibration control method includes the following steps: During the extremely hot start-up of the unit, close the heating steam valve under the swirl film tube to cut off the initial deaeration heating steam supply; Open the heating steam valve under the water-spraying grate to supply deep deoxygenated heating steam; Adjust the opening of the heating steam valve under the water spray grate to ensure that the deep deaeration heating steam is fully mixed with the water coming down from the water spray grate, preventing excess superheated steam from entering the swirl tube or condensate tube, thereby eliminating deaerator vibration.

[0007] Furthermore, a high-pressure drain pipe is connected to the deaerator shell above the water spray grate, and a drain shut-off valve and a drain valve are connected to the high-pressure drain pipe. During the initial stage of the unit's extremely hot start-up, the drain shut-off valve and drain valve are kept closed to prevent the low-temperature high-pressure drain from directly entering the high-temperature deaerator shell and causing localized severe thermal shock. After the unit's operation stabilizes and the internal operating conditions of the deaerator become stable, they are gradually opened according to the operating procedures.

[0008] Furthermore, the main pipe of the four-section extraction steam pipe is also equipped with a plant auxiliary steam pipe, and the head end of both the main pipe of the four-section extraction steam pipe and the plant auxiliary steam pipe is equipped with an extraction steam shut-off valve. During the extremely hot start-up phase of the unit, when the pressure or temperature of the four-section extraction steam is insufficient as an effective main heating steam source, the extraction steam shut-off valve on the plant auxiliary steam pipe is opened, and the plant auxiliary steam is used as a supplement or main heating steam source for the steam chamber below the water spray grate.

[0009] Furthermore, the feedwater tank is connected to a continuous expansion tank pipe, which is equipped with an expansion shut-off valve and an expansion valve. During the extremely hot start-up process, the steam flow rate returning from the continuous expansion tank is controlled by adjusting the opening of the expansion valve, so as to help maintain the stability of the pressure and temperature in the feedwater tank and reduce the vibration induced by pressure fluctuations.

[0010] Furthermore, a reboiling pipe is connected to the water supply tank, and a boiling pipe electric valve is connected to the reboiling pipe; during the extremely hot start-up process, the boiling pipe electric valve is kept in the closed state to avoid introducing additional steam source at the bottom of the water chamber of the water supply tank, prevent interference with the thermal stratification state of the water in the water tank and induce vibration of the inlet pipe of the water supply pre-pump.

[0011] Furthermore, a valve stem leakage pipe is connected to the water supply tank, and a valve stem shut-off valve is connected to the valve stem leakage pipe; during the extremely hot start-up process, the valve stem shut-off valve is kept in the open state, allowing low-pressure valve stem leakage steam to enter the steam space of the water supply tank as a mild supplementary heat source, which helps to gradually improve the uniformity of the medium inside the water tank.

[0012] Furthermore, at least one pre-pump inlet pipe is connected to the feedwater tank, and an electric valve is connected to the pre-pump inlet pipe. During the extremely hot start-up process, the water supply flow from the feedwater tank to the downstream feedwater pre-pump is adjusted by controlling the opening and closing or the opening degree of the electric valve, so as to match it with the makeup water flow and the boiler water demand, so as to avoid drastic changes in the water level of the feedwater tank, thereby reducing pressure and temperature oscillations caused by water level fluctuations.

[0013] Furthermore, the water supply tank is connected to at least three overflow pipes, each of which is connected to an electric two-way shut-off valve. The water supply tank is equipped with a liquid level sensor, which is electrically connected to at least one of the electric two-way shut-off valves. During the extremely hot start-up process, when the liquid level sensor detects that the water level exceeds the high safety threshold, it automatically interlocks and opens the corresponding electric two-way shut-off valve, releasing water urgently through the overflow pipe to prevent excessively high water levels from causing steam carryover or abnormal pressure, thereby suppressing related vibrations.

[0014] Furthermore, it also includes intelligent control steps based on large models, which include: Configure a data acquisition system, which includes: The first vibration sensor, installed on the deaerator housing, is used to collect real-time vibration acceleration data of the deaerator head. The second vibration sensor installed on the water tank is used to collect the vibration acceleration data of the water tank in real time. Flow meters and thermometers installed on condensate pipes or water supply pipes are used to collect real-time water supply flow and temperature data. The water level gauge and the layered temperature sensor installed in the water supply tank are used to collect real-time water level and water temperature data of the upper, middle and lower parts of the tank. The pressure and temperature sensors installed inside the deaerator housing are used to collect real-time pressure and temperature data of the deaerator head. Valve position sensors installed on the steam branch valve of the water sprayer and the steam valve of the swirl film tube are used to collect valve opening data in real time. The intelligent control system includes a processor and a memory. The memory stores a trained large model, which is configured to be trained based on a historical operating dataset. The historical operating dataset includes at least: time-series vibration data, thermodynamic parameter data, water supply parameter data, steam valve opening data, and their corresponding vibration result labels for multiple startup processes. The large model is used to dynamically predict future vibration trends based on the real-time collected vibration data, thermodynamic parameter data, and water supply parameter data, and output optimized opening control commands for the steam branch valve of the water sprayer heating pipe.

[0015] Furthermore, the intelligent control steps based on large models specifically include: S1: Initial operating procedure: At the start of the unit's extremely hot start-up process, close the steam valve for the rotating film tube heating and open the steam branch valve for the water spray grate heating to a preset safe opening degree; S2: Data perception and input steps: Vibration data, thermal parameter data, water replenishment parameter data and current valve opening data are collected in real time through the data acquisition system and input into the large model; S3: Model Prediction and Decision-Making Steps: The large model takes the time series data of the current and historical time windows as input, and predicts the vibration intensity change under different opening degrees of the steam branch valve of the water-sprinkling grate in the future through the internally learned mapping relationship; under the constraints of the vibration intensity being lower than the preset safety threshold and maintaining the deoxygenation effect and water level requirements, an optimal valve opening value is calculated. S4: Control Execution Step: The intelligent control system converts the optimal valve opening value obtained in step S3 into a control signal to drive the steam branch valve of the water sprayer to adjust to that opening. S5: Feedback adjustment step: Continuously execute steps S2 to S4 to form closed-loop control; The large model performs online correction or fine-tuning of the prediction model based on the actual vibration data and thermodynamic parameter changes collected after valve adjustment, so as to achieve adaptive optimization control. The control objectives include minimizing vibration amplitude, maintaining stable water level in the tank, and optimizing unit start-up time.

[0016] Beneficial effects The present invention has the following beneficial effects: (1) By closing the heating steam valve of the swirl film tube and precisely controlling the opening of the heating steam branch valve of the water sprayer, the present invention fundamentally prevents overheated steam from entering the low-temperature water inlet pipe or damaging the thermal stratification of the water tank, thereby successfully suppressing vibration, effectively suppressing equipment vibration, and ensuring operational safety.

[0017] (2) By optimizing the method and timing of the introduction of heating steam, the present invention achieves a rapid and stable heating process, shortens the unit start-up time, and improves economic efficiency.

[0018] (3) By precisely controlling the valves of the high-pressure drain pipe, the continuous expansion tank pipe, the pre-pump inlet pipe, and other pipelines, and by making reasonable use of the valve stem leakage pipe, the present invention effectively stabilizes the pressure, temperature and water level in the deaerator, ensures the stability of system parameters and optimizes the operating conditions.

[0019] (4) The present invention can predict the vibration trend and dynamically adjust the valve opening based on real-time data through intelligent control steps based on large models, forming a closed-loop optimization. It achieves a fundamental improvement from "passive response and open-loop operation" that relies on fixed rules and human experience to "active intervention and adaptive closed-loop" intelligent control, reducing the operational burden and risk of misoperation of operators, realizing intelligent adaptive control, reducing the operational burden, and improving the adjustment rate of vibration suppression, so that vibration can be suppressed more effectively.

[0020] Of course, any product implementing this invention does not necessarily need to achieve all of the advantages described above at the same time. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the overall invention.

[0022] Figure 2 This is a flowchart of the intelligent control system of the present invention.

[0023] Figure reference numerals: 1. Condensate pipe; 11. Condensate shut-off valve; 12. Make-up water pipe; 2. High-pressure drain pipe; 21. Drain shut-off valve; 22. Drain valve; 3. Four-section extraction steam pipe; 31. Auxiliary steam pipe for plant use; 32. Heating steam valve under water spray grate; 33. Heating pipe under film swirl tube; 34. Extraction steam shut-off valve; 35. Reboiler pipe; 4. Boiler pipe electric valve; 41. Feed water tank; 5. Pre-pump inlet pipe; 51. Overflow pipe; 52. Electric two-way shut-off valve; 53. Electric valve; 54. Deaerator shell; 6. Heat storage packing; 61. Water spray grate; 62. Film swirl tube; 63. Connecting expansion tank pipe; 7. Expansion shut-off valve; 71. Expansion valve; 72. Gate valve steam leakage pipe; 8. Gate valve shut-off valve; 81. Drain pipe; 9. Liquid level sensor; 10. Detailed Implementation

[0024] 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.

[0025] Please see Figures 1-2 This invention provides a technical solution: a vibration control method for a high-pressure swirl film deaerator. The high-pressure swirl film deaerator structure includes a deaerator shell 6, inside which, from bottom to top, are arranged a heat storage packing 61, a water spray grate 62, and a swirl film tube 63. The bottom of the deaerator shell 6 is connected to a water supply tank 5 via a drain pipe 9. A condensate pipe 1 is connected to the deaerator shell 6, and the condensate pipe 1 enters the deaerator shell 6 and is connected to the inlet water chamber of the swirl film tube 63 for conveying main condensate. The steam chamber of the deaerator shell 6 is connected to four sections of extraction steam pipe 3, which serve as the main heating steam source. A water spray grate heating steam branch valve 32 is provided on the main pipe of the four sections of extraction steam pipe 3 for controlling the steam flowing to the steam chamber below the water spray grate 62. An independent steam interface is provided on the deaerator shell 6 below the swirl film tube 63, which is connected to the main pipe of the four-section extraction steam pipe 3 via the swirl film tube heating branch pipe 33; the swirl film tube heating branch pipe 33 is equipped with a swirl film tube heating steam valve 34, which is used to control the heating steam leading to the area of ​​the swirl film tube 63; a condensate shut-off valve 11 is provided on the condensate pipe 1, and a makeup water pipe 12 is connected to the end of the condensate pipe 1. The makeup water source of the makeup water pipe 12 includes at least one of the following: low-pressure deaerator outlet water and unit condensate makeup water; the vibration control method includes the following steps: During the extremely hot start-up of the unit, the heating steam valve 34 below the swirl film tube is closed to cut off the supply of initial deaeration heating steam; Open the heating steam valve 32 under the water sprayer to supply deep deoxygenated heating steam; Adjust the opening of the heating steam valve 32 under the water sprayer to fully mix the deep deaeration heating steam with the water coming down from the water sprayer 62, preventing excess superheated steam from entering the swirl tube 63 or condensate tube 1, thereby eliminating deaerator vibration.

[0026] In practical implementation, the vibration control method of the present invention eliminates vibration by using a specific steam valve operation mode during the extremely hot start-up of the unit.

[0027] The specific operating steps are as follows: First, confirm that the unit is in a state of extremely hot startup (shutdown time less than 8 hours, equipment temperature still close to operating temperature). At this time, the internal pressure of the deaerator is approximately 0.8-0.9 MPa, and the temperature is maintained at 130-140℃. The operator remotely closes the heating steam valve 34 of the swirl film tube via the DCS system, setting the valve opening to 0%, completely cutting off the initial deaeration heating steam to the swirl film tube 63 area. Simultaneously, the opening of the heating steam branch valve 32 of the water-sprinkling grate is set to 100%, ensuring a sufficient supply of deep deaeration heating steam. By adjusting the opening of the heating steam branch valve 32 of the water-sprinkling grate, the steam flow rate is controlled within the range of 200-300 kg / h, ensuring thorough mixing of the steam with the water coming down from the water-sprinkling grate 62, and preventing overheated steam from entering the upper area. The effectiveness of this operating method lies in the fact that when the condensate flow rate is low (usually below 50 t / h), shutting off the heating steam in the swirl film tube prevents steam from flowing back into the swirl film tube or condensate tube 1, thereby eliminating the bubble burst vibration caused by direct contact between hot and cold media. Practical application shows that this scheme can shorten the unit's extremely hot start-up time from more than 5 hours to less than 2 hours, and the vibration values ​​of all parts of the deaerator are controlled within the safe range of 4.5 mm / s.

[0028] Furthermore, a high-pressure drain pipe 2 is connected to the deaerator shell 6 above the water-spraying grate 62. A drain shut-off valve 21 and a drain valve 22 are connected to the high-pressure drain pipe 2. During the initial stage of the unit's extremely hot start-up, the drain shut-off valve 21 and the drain valve 22 are kept closed to prevent low-temperature high-pressure drain from directly entering the high-temperature deaerator shell 6 and causing localized severe thermal shock. After the unit's operation stabilizes and the internal working conditions of the deaerator become stable, they are gradually opened according to the operating procedures.

[0029] In practice, the control strategy for the high-pressure condensate drain pipe 2 needs to be dynamically adjusted according to the startup phase. During the initial stage of extremely hot startup (within 30 minutes after boiler ignition), operators keep the drain shut-off valve 21 and drain valve 22 fully closed. This is because the internal temperature of the deaerator is high at this time (approximately 140℃), while the high-pressure condensate temperature is relatively low (approximately 80-100℃), and direct introduction would cause severe localized thermal shock. After the unit has been running for one hour, the internal operating conditions of the deaerator tend to stabilize, and operators can gradually open the drain valve 22, initially controlling the opening at 10-15%. After observing that the deaerator vibration is normal, the opening can be slowly increased at a rate of 5% per minute until fully open. This gradual opening method effectively avoids thermal stress caused by sudden temperature changes while ensuring the normal recovery of high-pressure condensate. Actual operating data shows that after adopting this control method, the peak vibration acceleration of the deaerator during the introduction of high-pressure condensate never exceeded 2.5 m / s², far below the safety threshold.

[0030] Furthermore, the main pipe of the four-section extraction steam pipe 3 is also equipped with a plant auxiliary steam pipe 31, and the head end of both the main pipe of the four-section extraction steam pipe 3 and the plant auxiliary steam pipe 31 is equipped with an extraction steam shut-off valve 35. During the extremely hot start-up phase of the unit, when the pressure or temperature of the four-section extraction steam is insufficient as an effective main heating steam source, the extraction steam shut-off valve 35 on the plant auxiliary steam pipe 31 is opened, and the plant auxiliary steam is used as a supplement or main heating steam source for the steam chamber below the water spray grate 62.

[0031] In practice, the auxiliary steam pipe 31 serves as a backup steam source. During a hot start-up of the unit, operators first monitor the steam parameters of the four-section extraction pipe 3. If the pressure is below 0.7 MPa or the temperature is below 160°C, the main steam source is considered insufficient. At this time, the operator opens the extraction shut-off valve 35 on the auxiliary steam pipe 31, initially controlling the opening at 20-30%, to introduce auxiliary steam (pressure 0.8-1.0 MPa, temperature 200-250°C). Special attention must be paid to matching the steam parameters during commissioning. By adjusting the opening of the extraction shut-off valve 35, the temperature difference between the mixed steam and the deaerator should be controlled within 30°C. This timely commissioning of the backup steam source ensures a continuous and stable supply of heating steam, avoiding temperature fluctuations and vibrations caused by insufficient steam. Statistical data shows that in 20 hot starts-ups, the auxiliary steam was successfully commissioned 6 times, and no abnormal vibrations caused by steam source switching occurred.

[0032] Furthermore, the water supply tank 5 is connected to a continuous expansion vessel pipe 7, which is equipped with an expansion shut-off valve 71 and an expansion valve 72. During the extremely hot start-up process, the steam flow rate returning from the continuous expansion vessel is controlled by adjusting the opening of the expansion valve 72, so as to help maintain the pressure and temperature stability in the water supply tank 5 and reduce the vibration induced by pressure fluctuations.

[0033] In practical implementation, the adjustment of the expansion valve 7 is crucial for maintaining stable system pressure. Operators monitor the internal pressure of the feedwater tank 5 in real time via the DCS system. When pressure fluctuations exceed ±0.05 MPa, adjustment of the expansion valve 72 begins. The adjustment strategy employs proportional-integral control, initially making small adjustments (5-10%) and gradually adjusting according to pressure change trends. When the makeup water flow suddenly increases (e.g., from 50 t / h to 80 t / h), the opening of the expansion valve 72 needs to be increased by 15-20% beforehand to buffer pressure surges. Actual operation shows that this active pressure control strategy can control pressure fluctuations within ±0.02 MPa during extremely hot start-up, effectively suppressing vibrations induced by pressure fluctuations.

[0034] Furthermore, a reboiling pipe 4 is connected to the water supply tank 5, and a boiling pipe electric valve 41 is connected to the reboiling pipe 4; during the extremely hot start-up process, the boiling pipe electric valve 41 is kept in the closed state to avoid introducing additional steam source at the bottom of the water chamber of the water supply tank 5, to prevent interference with the thermal stratification state of the water in the water tank and to prevent vibration of the inlet pipe of the water supply pre-pump.

[0035] In practice, the reboiling tube 4 is controlled. During the entire extremely hot start-up process (approximately 2 hours), the operator keeps the electric valve 41 of the reboiling tube fully closed. Because there is significant temperature stratification at the bottom of the feedwater tank 5, with the upper part at approximately 140°C and the lower part at approximately 120°C, introducing reboiling steam would disrupt this thermal stratification, causing the lower water to vaporize rapidly. Only after the unit is running normally and the temperature difference between the upper and lower parts of the feedwater tank 5 is less than 5°C is the electric valve 41 of the reboiling tube allowed to be slowly opened. This strict control measure effectively prevents cavitation vibration in the feedwater pre-pump inlet pipe. Actual vibration monitoring data shows that, with the reboiling tube closed, the vibration value of the pre-pump inlet pipe remains below 3.5 mm / s.

[0036] Furthermore, a valve stem leakage pipe 8 is connected to the water supply tank 5, and a valve stem shut-off valve 81 is connected to the valve stem leakage pipe 8. During the extremely hot start-up process, the valve stem shut-off valve 81 is kept in the open state, allowing low-pressure valve stem leakage steam to enter the steam space of the water supply tank 5 as a mild supplementary heat source, which helps to gradually improve the uniformity of the medium inside the water tank.

[0037] In practical implementation, the function of the gate valve steam leakage pipe 8 is as follows: During the initial stage of extremely hot startup, the operator keeps the gate valve shut-off valve 81 fully open, allowing steam leakage from the gate valve at a pressure of 0.1-0.2 MPa and a temperature of 120-150℃ to continuously enter the feedwater tank 5. This method of introducing low-temperature, low-pressure steam is gentle and will not cause drastic temperature changes, while providing approximately 50-100 kW of heat compensation. Especially when the makeup water temperature is low (approximately 40℃), the continuous heating from the gate valve steam leakage can effectively mitigate thermal shock. Operational data shows that proper utilization of the gate valve steam leakage can reduce the rate of temperature drop inside the feedwater tank 5 from the original 5℃ / min to 2℃ / min, improving temperature stability.

[0038] Furthermore, at least one pre-pump inlet pipe 51 is connected to the feedwater tank 5, and an electric valve 54 is connected to the pre-pump inlet pipe 51. During the extremely hot start-up process, by controlling the opening and closing or the opening degree of the electric valve 54, the water supply flow from the feedwater tank 5 to the downstream feedwater pre-pump is adjusted to match the makeup water flow and the boiler water demand, so as to avoid the water level of the feedwater tank 5 changing drastically, thereby reducing the pressure and temperature oscillations caused by water level fluctuations.

[0039] In practical implementation, the control of the pre-pump inlet pipe 51 is crucial. Operators control the flow rate via electric valve 54 based on the water level changes in the feedwater tank 5: when the water level is below 2400mm, the opening of electric valve 54 is controlled at 30-50%; when the water level is between 2400-2600mm, the opening is adjusted to 50-70%; and when the water level is above 2600mm, the opening can be increased to 80-100%. This tiered control ensures dynamic matching between the supply flow rate, the makeup flow rate, and the boiler demand, avoiding drastic water level fluctuations. In actual operation, this control strategy keeps water level fluctuations within ±50mm, reducing pressure oscillations caused by water level changes.

[0040] Furthermore, at least three overflow pipes 52 are connected to the water tank 5, and each overflow pipe 52 is connected to an electric two-way shut-off valve 53. The water tank 5 is equipped with a liquid level sensor 10, which is electrically connected to at least one of the electric two-way shut-off valves 53. During the extremely hot start-up process, when the liquid level sensor 10 detects that the water level exceeds the high safety threshold, it automatically interlocks and opens the corresponding electric two-way shut-off valve 53, and releases water urgently through the overflow pipe 52 to prevent the water level from being too high, which could lead to steam carrying water or abnormal pressure, thereby suppressing related vibrations.

[0041] In practical implementation, the overflow pipe 52 is controlled. Three electrically operated bidirectional shut-off valves 53 are each set with different trigger water levels: the first stage opens to 30% at 2800mm, the second stage opens to 60% at 2850mm, and the third stage opens fully at 2900mm. The level sensor 10 employs a triple redundancy configuration to ensure signal reliability. When the water level exceeds 2800mm, the DCS system automatically triggers the interlocking control program, sequentially opening the electrically operated bidirectional shut-off valves 53 according to preset logic. This staged pressure relief method ensures safety while avoiding system shock caused by sudden full opening. Practical application shows that the protection system successfully operated in 10 cases of abnormal water levels, effectively preventing vibration problems caused by excessively high water levels.

[0042] Furthermore, it also includes intelligent control steps based on large models, which include: Configure a data acquisition system, which includes: The first vibration sensor installed on the deaerator housing 6 is used to collect the vibration acceleration data of the deaerator head in real time. The second vibration sensor installed on the water tank 5 is used to collect the vibration acceleration data of the water tank in real time. The flow meter and thermometer installed on the condensate pipe 1 or the water supply pipe 12 are used to collect water supply flow and water supply temperature data in real time. The water level gauge and the layered temperature sensor installed in the water supply tank 5 are used to collect real-time water level and water temperature data of the upper, middle and lower parts of the tank. The pressure sensor and temperature sensor installed inside the deaerator housing 6 are used to collect real-time pressure and temperature data of the deaerator head. Valve position sensors installed on the steam branch valve 32 for water spraying grate heating and the steam valve 34 for rotating film tube heating are used to collect valve opening data in real time. The intelligent control system includes a processor and a memory. The memory stores a trained large model, which is configured to be trained based on a historical operating dataset. The historical operating dataset includes at least: time-series vibration data, thermodynamic parameter data, water supply parameter data, steam valve opening data, and their corresponding vibration result labels for multiple startup processes. The large model is used to dynamically predict future vibration trends based on the real-time collected vibration data, thermodynamic parameter data, and water supply parameter data, and output optimized opening control commands for the steam branch valve 32 of the water-sprinkling grate heating pipe.

[0043] In practice, fine-tuning training is based on a large model.

[0044] The operating environment and training methods for large models utilize existing technologies.

[0045] The training data is a historical operational dataset of a high-pressure rotary film deaerator. Data acquisition.

[0046] The original dataset required for model training was constructed. During the unit's extremely hot start-up, key time-series data were synchronously acquired at a frequency of 1Hz. The necessary data to be acquired included: core vibration signals reflecting equipment status (a_head of the deaerator shell 6 and a_tank of the feedwater tank 5); core parameters characterizing the system's thermodynamic state (deaerator head pressure p_head, temperature T_head, water tank level L_tank, and water temperatures at each level T_tank_top / mid / bot); and key control and makeup water variables (makeup water flow rate F_makeup, temperature T_makeup, and the command opening degrees u_shower, u_film of the steam branch valve 32 for the water spray grate and the steam valve 34 for the swirl film tube). Simultaneously, based on the acquired vibration data, a binary vibration risk label y_vib (1 indicating high risk, 0 indicating normal) was generated for each moment of data, with a threshold of max(a_head, a_tank) >= 4.0 mm / s², for subsequent supervised learning. The original dataset D_raw is generated by repeatedly starting the data collection process.

[0047] Data preparation and sample construction The raw data is processed and transformed into structured samples that the model can learn (based on the selected large model). First, necessary preprocessing is performed: timestamps of all sensor data are aligned, and missing values ​​are imputed; vibration signals are low-pass filtered to remove high-frequency noise; and all numerical features are Z-score standardized to accelerate model convergence. Next, a sliding window method is used to construct training samples: for each time t, all feature data from the past 300 seconds are used to form the input sequence X(t); the output target Y(t) consists of two parts: a classification target y_pred_vib (predicting whether a high vibration risk will occur within the next 60 seconds) and a regression target Δu (the recommended optimal opening adjustment for the steam branch valve 32 of the water-sprinkling grate heating pipe). The classification label is determined based on future actual vibration data, while the regression label is learned backward from successful "smooth start" operations in the past. Finally, the processed dataset is divided into a training set D_train, a validation set D_val, and a test set D_test in a 7:2:1 ratio.

[0048] Model fine-tuning training The pre-trained model is trained using pre-processed data. First, a suitable large pre-trained model for time series analysis (such as a Transformer-based model) is selected, and its input and output layers are adapted: the input layer needs to match the sequence length and feature dimension of X(t); the output layer is designed as a dual-task output head, one outputting the vibration risk probability P_vib via a sigmoid function, and the other directly outputting the valve opening adjustment Δu. Second, a combined loss function L_total = α * L_vib + β * L_control is defined, where L_vib is the binary cross-entropy loss for vibration prediction, and L_control is the smooth mean square error loss of the control command. This design aims to simultaneously optimize prediction accuracy and control smoothness. The training process involves loading pre-trained weights, performing multiple iterations on D_train using an optimizer (such as Adam) to minimize the total loss, validating the performance on D_val after each iteration, employing an "early stopping" strategy to prevent overfitting, and finally saving the model that performs best on the validation set.

[0049] Model Validation and Iterative Deployment To evaluate model performance and promote its safe and effective practical application, offline testing was first conducted on an independent test set, D_test, to evaluate the model's accuracy and recall in predicting vibration risks, and to analyze the consistency between its control recommendations and historical expert operations. Next, high-fidelity simulation testing was performed, integrating the model into the simulation environment of the deaerator system to simulate various extreme start-up conditions. The core verification indicator was whether the system vibration under model control could be stably suppressed below the safe threshold of 4.5 mm / s. After successful simulation, a "human-in-the-loop" field trial run was initiated: during the startup of the actual unit, the model, acting as an auxiliary decision-making system, provided valve operation suggestions, which were then reviewed and executed by the operator, with the system simultaneously recording operational data. Finally, the performance of model-assisted and purely manual operations was compared (e.g., the number of vibration exceedances and start-up time), and the model was periodically iterated and trained using new data accumulated during the trial run, thereby achieving continuous optimization and generalization of the control strategy.

[0050] Furthermore, the intelligent control steps based on large models specifically include: S1: Initial operating procedure: At the start of the unit's extremely hot start-up process, close the swirl film tube heating steam valve 34 and open the water spray grate heating steam branch valve 32 to a preset safe opening degree; S2: Data perception and input steps: Vibration data, thermal parameter data, water replenishment parameter data and current valve opening data are collected in real time through the data acquisition system and input into the large model; S3: Model Prediction and Decision-Making Steps: The large model takes the time series data of the current and historical time windows as input, and predicts the vibration intensity change of different water-sprinkling grate heating steam branch valves at 32 opening degree in the future through the internally learned mapping relationship; under the constraints of the vibration intensity being lower than the preset safety threshold and maintaining the deoxygenation effect and water level requirements, an optimal valve opening degree value is calculated. S4: Control execution step: The intelligent control system converts the optimal valve opening value obtained in step S3 into a control signal, and drives the steam branch valve 32 of the water sprayer to adjust to the opening degree. S5: Feedback adjustment step: Continuously execute steps S2 to S4 to form closed-loop control; The large model performs online correction or fine-tuning of the prediction model based on the actual vibration data and thermodynamic parameter changes collected after valve adjustment, so as to achieve adaptive optimization control. The control objectives include minimizing vibration amplitude, maintaining stable water level in the tank, and optimizing unit start-up time.

[0051] In practice, the intelligent control unit automatically executes the basic safety strategy, namely, remotely closing the steam valve 34 of the swirl film tube heating system through the distributed control system (DCS); at the same time, opening the steam branch valve 32 of the water sprayer heating system to a preset 30% safety opening degree. Subsequently, the S2 data sensing and input step begins, where the configured data acquisition unit starts acquiring key parameters in real time at a frequency of 1 Hz. These parameters include: vibration acceleration a_head (vibration data) measured by the first vibration sensor installed on the deaerator housing 6; vibration acceleration a_tank (vibration data) measured by the second vibration sensor installed on the feed water tank 5; pressure p_head (pressure) measured by the pressure sensor inside the deaerator housing 6 and temperature T_head (temperature) measured by the temperature sensor; feed water flow rate F_makeup (feed water flow rate) measured by the flow meter on the feed water pipe 12 and feed water temperature T_makeup (feed water flow rate) measured by the thermometer; water level L_tank (temperature) measured by the water level gauge inside the feed water tank 5; and actual opening degree pos_shower (valve opening degree data) fed back by the valve position sensor on the steam branch valve 32 of the water sprayer heating pipe. This real-time data is continuously packaged into a time-series data stream and input into the deployed large model.

[0052] The large model uses historical time-series data from the current moment and the previous 5 minutes (300 seconds) as input for high-speed inference calculations. Trained on a large amount of historical extremely hot startup data, the model, through its internally learned complex nonlinear mapping relationships, can not only predict the development trend of vibration of the water-sprinkler heating steam branch valve 32 within the next 60 seconds if the current opening degree is maintained, but also simulate and compare the comprehensive changes in vibration intensity, deoxygenation effect, and water level L_tank stability under different opening degrees of the water-sprinkler heating steam branch valve 32. At a certain moment during this startup, when the model senses that the makeup water temperature T_makeup is low (approximately 50 degrees Celsius) and the makeup water flow rate F_makeup is increasing, it calculates an optimal solution through an optimization algorithm under multiple constraints, strictly meeting the safety threshold of vibration intensity below 4.0 mm / s², achieving the deoxygenation effect, and maintaining water level stability: it recommends increasing the opening degree of the water-sprinkler heating steam branch valve 32 from the current 30% to 38%. The S4 control execution step is then initiated. The intelligent control unit converts the calculated optimal valve opening value into a control command, driving the actuator of the steam branch valve 32 of the water-sprinkling grate to precisely adjust to an opening of 38%. Afterward, the S5 feedback adjustment step is initiated, forming a closed-loop control. During the subsequent approximately 20-minute critical startup period, the large model dynamically fine-tunes and corrects its predictive model online based on the actual vibration data and thermodynamic parameter changes collected after valve adjustment, thereby adaptively outputting subsequent control commands.

[0053] This represents a fundamental improvement, moving from a "passive response, open-loop operation" mode reliant on fixed rules and operator experience to an "active intervention, adaptive closed-loop" intelligent control mode based on multi-objective real-time prediction and optimization. The maximum vibration value at each point of the high-pressure rotary film deaerator was successfully suppressed to within 3.2 mm / s², exceeding the safety standard of 4.5 mm / s². The water level fluctuation in the feedwater tank was controlled within ±30 mm. Simultaneously, by precisely controlling the heating steam injection process, the total start-up time under extreme heat was reduced from approximately 5 hours in the traditional mode to approximately 1.8 hours. The intelligent control system, through proactive vibration suppression intervention, fundamentally prevented severe vibrations, ensuring the structural safety of the deaerator, pipelines, and related equipment. By optimizing steam utilization efficiency and significantly shortening start-up time, it improved the unit's operational economy. Furthermore, its highly automated control effectively reduced the operational burden on operators and the risk of misoperation due to human error.

[0054] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0055] The preferred embodiments of the present invention disclosed above are merely illustrative of the invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the invention to the specific implementations described. Clearly, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize the invention. The invention is limited only by the claims and their full scope and equivalents.

Claims

1. A vibration control method for a high-pressure swirl film deaerator, wherein the high-pressure swirl film deaerator structure includes a deaerator shell (6), inside which, from bottom to top, are arranged heat storage packing (61), a water spraying grate (62), and a swirl film tube (63); the bottom of the deaerator shell (6) is connected to a water supply tank (5) via a drain pipe (9); a condensate pipe (1) is connected to the deaerator shell (6), the condensate pipe (1) is connected to the deaerator shell (6) and to the inlet water chamber of the swirl film tube (63), for conveying main condensate; the steam chamber of the deaerator shell (6) is connected to four sections of extraction steam pipe (3), the four sections of extraction steam pipe (3) being connected as the main heating steam source; a water spraying grate heating steam branch valve (32) is provided on the main pipe of the four sections of extraction steam pipe (3), for controlling the steam leading to the steam chamber below the water spraying grate (62); characterized in that: An independent steam interface is provided on the deaerator shell (6) below the swirl film tube (63), which is connected to the main pipe of the four-section extraction steam pipe (3) through the swirl film tube heating branch pipe (33); a swirl film tube heating steam valve (34) is provided on the swirl film tube heating branch pipe (33) to control the heating steam leading to the swirl film tube (63) area; a condensate shut-off valve (11) is provided on the condensate pipe (1), and a water supply pipe (12) is connected to the end of the condensate pipe (1). The water supply source of the water supply pipe (12) includes at least one of the following: low-pressure deaerator outlet water and unit condensate water supply water; the vibration control method includes the following steps: During the extremely hot start-up of the unit, the heating steam valve (34) under the swirl film tube is closed to cut off the supply of initial deoxygenation heating steam; Open the heating steam valve (32) under the water-spraying grate to supply deep deoxygenation heating steam; Adjust the opening of the heating steam valve (32) under the water spraying grate to fully mix the deep deoxygenation heating steam with the water coming down from the water spraying grate (62), and prevent excess superheated steam from entering the swirl tube (63) or condensate tube (1), thereby eliminating the vibration of the deaerator.

2. The vibration control method for a high-pressure rotary film deaerator according to claim 1, characterized in that: A high-pressure drain pipe (2) is connected to the deaerator shell (6) located above the water spray grate (62). A drain shut-off valve (21) and a drain valve (22) are connected to the high-pressure drain pipe (2). During the initial stage of the unit's extremely hot start-up, the drain shut-off valve (21) and the drain valve (22) are kept closed to prevent the low-temperature high-pressure drain from directly entering the high-temperature deaerator shell (6) and causing localized severe thermal shock. After the unit's operation becomes stable and the internal working conditions of the deaerator are stable, the drain pipe is gradually opened according to the operating procedures.

3. The vibration control method for a high-pressure rotary film deaerator according to claim 1, characterized in that: The main pipe of the four-section extraction steam pipe (3) is also equipped with a plant auxiliary steam pipe (31). The head end of the main pipe of the four-section extraction steam pipe (3) and the plant auxiliary steam pipe (31) are equipped with extraction steam shut-off valves (35). During the extremely hot start-up phase of the unit, when the extraction steam pressure or temperature of the four sections is insufficient as an effective main heating steam source, the extraction steam shut-off valve (35) on the plant auxiliary steam pipe (31) is opened, and the plant auxiliary steam is used as a supplement or main heating steam source for the steam chamber below the water spraying grate (62).

4. The vibration control method for a high-pressure rotary film deaerator according to claim 1, characterized in that: The water supply tank (5) is connected to a continuous expansion container pipe (7), which is equipped with an expansion shut-off valve (71) and an expansion valve (72). During the extremely hot start-up process, the steam flow rate returning from the continuous expansion container is controlled by adjusting the opening of the expansion valve (72) to help maintain the pressure and temperature stability in the water supply tank (5) and reduce the vibration induced by pressure fluctuations.

5. The vibration control method for a high-pressure rotary film deaerator according to claim 1, characterized in that: A reboiling pipe (4) is connected to the water tank (5), and a boiling pipe electric valve (41) is connected to the reboiling pipe (4). During the extremely hot start-up process, the boiling pipe electric valve (41) is kept in the closed state to avoid introducing additional steam source at the bottom of the water chamber of the water tank (5), prevent interference with the thermal stratification state of the water in the water tank and induce vibration of the inlet pipe of the water supply pre-pump.

6. The vibration control method for a high-pressure rotary film deaerator according to claim 1, characterized in that: The water supply tank (5) is connected to a gate valve steam pipe (8), and the gate valve steam pipe (8) is connected to a gate valve shut-off valve (81). During the extremely hot start-up process, the gate valve shut-off valve (81) is kept in the open state, allowing low-pressure gate valve steam to enter the steam space of the water supply tank (5) as a mild supplementary heat source, which helps to gradually improve the uniformity of the medium inside the water tank.

7. The vibration control method for a high-pressure rotary film deaerator according to claim 1, characterized in that: At least one pre-pump inlet pipe (51) is connected to the water supply tank (5), and an electric valve (54) is connected to the pre-pump inlet pipe (51). During the extremely hot start-up process, by controlling the opening and closing or the opening degree of the electric valve (54), the water supply flow from the water supply tank (5) to the downstream water supply pre-pump is adjusted so that it matches the water replenishment flow and the boiler water demand, thereby avoiding a sharp change in the water level of the water supply tank (5) and reducing the pressure and temperature oscillations caused by water level fluctuations.

8. The vibration control method for a high-pressure rotary film deaerator according to claim 1, characterized in that: At least three overflow pipes (52) are connected to the water tank (5), and each overflow pipe (52) is connected to an electric two-way shut-off valve (53). A liquid level sensor (10) is installed inside the water tank (5), and the liquid level sensor (10) is electrically connected to at least one of the electric two-way shut-off valves (53). During the extremely hot start-up process, when the liquid level sensor (10) detects that the water level exceeds the high safety threshold, the corresponding electric two-way shut-off valve (53) is automatically opened in a chain, and water is urgently discharged through the overflow pipe (52) to prevent the water level from being too high, which could lead to steam carrying water or abnormal pressure, thereby suppressing related vibrations.

9. The vibration control method for a high-pressure rotary film deaerator according to claim 1, characterized in that, It also includes intelligent control steps based on a large model, which include: Configure a data acquisition system, the data acquisition system including: The first vibration sensor installed on the deaerator housing (6) is used to collect the vibration acceleration data of the deaerator head in real time; The second vibration sensor installed on the water tank (5) is used to collect the vibration acceleration data of the water tank in real time; The flow meter and thermometer installed on the condensate pipe (1) or the water supply pipe (12) are used to collect water supply flow and water supply temperature data in real time. The water level gauge and the layered temperature sensor installed in the water supply tank (5) are used to collect the water level and the water temperature data of the upper, middle and lower parts of the tank in real time. The pressure sensor and temperature sensor installed inside the deaerator housing (6) are used to collect deaerator head pressure and temperature data in real time. Valve position sensors installed on the steam branch valve (32) for heating the water sprayer and the steam valve (34) for heating the swirl film tube are used to collect valve opening data in real time. The intelligent control system includes a processor and a memory, the memory storing a trained large model configured to be trained based on a historical operating dataset, the historical operating dataset including at least: time-series vibration data, thermodynamic parameter data, water supply parameter data, steam valve opening data and their corresponding vibration result labels for multiple startup processes; the large model is used to dynamically predict future vibration trends based on the real-time collected vibration data, thermodynamic parameter data and water supply parameter data, and output optimized opening control commands for the steam branch valve (32) of the water-sprinkling grate heating pipe.

10. The vibration control method for a high-pressure rotary film deaerator according to claim 9, characterized in that, The intelligent control steps based on the large model specifically include: S1: Initial operation steps: At the start of the unit's extremely hot start-up process, close the swirl film tube heating steam valve (34) and open the water spray grate heating steam branch valve (32) to a preset safe opening degree; S2: Data perception and input step: The vibration data, thermal parameter data, water replenishment parameter data and current valve opening data are collected in real time through the data acquisition system and input into the large model; S3: Model prediction and decision-making steps: The large model takes the time series data of the current and historical time windows as input, and predicts the vibration intensity change of different opening degrees of the steam branch valve (32) of the water-sprinkling grate heating pipe in the future through the internally learned mapping relationship; under the constraint that the vibration intensity is lower than the preset safety threshold and can maintain the deoxygenation effect and water level requirements, an optimal valve opening value is calculated. S4: Control execution step: The intelligent control system converts the optimal valve opening value obtained in step S3 into a control signal and drives the water-sprinkling grater heating steam branch valve (32) to adjust to the opening degree; S5: Feedback adjustment step: Continuously execute steps S2 to S4 to form closed-loop control; The large model performs online correction or fine-tuning of the prediction model based on the vibration data and thermodynamic parameter changes actually collected after valve adjustment, so as to achieve adaptive optimization control. The control objectives include minimizing vibration amplitude, maintaining stable water level in the tank, and optimizing unit start-up time.

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