Corrosion monitoring and protection method for boiler tail flue gas waste heat exchange equipment

Abstract

The application provides a corrosion monitoring and protection method of a boiler tail flue gas waste heat exchange equipment, first, collecting flue gas, condensate water and heat pump / melt salt energy storage system working condition parameters, identifying core corrosion factors, and combining with flow field simulation to predict the corrosion grade of each part of the equipment and mark the key points; then, determining multi-dimensional monitoring indicators, selecting and adapting monitoring equipment, and building a distributed corrosion monitoring system; then, combining with the working condition parameter account, initially selecting the monitoring points, verifying and adjusting the point arrangement density, fixing the monitoring equipment and completing the interface sealing protection; based on this, the application carries out multi-corrosion factor linkage monitoring by fusing the multi-dimensional working condition parameters of flue gas, condensate water and heat pump / melt salt energy storage system, has the effect of realizing accurate tracing of corrosion types and directly matching the corrosion root with the protection measures.

Description

Technical Field

[0001] This invention relates to the technical field of waste heat recovery equipment for flue gas in the tail flue of coal-fired boilers, specifically a corrosion monitoring and protection method for such equipment. Background Technology

[0002] Waste heat utilization from the tail flue gas of coal-fired boilers is a key technology for improving energy efficiency and reducing enterprise energy consumption. The core heat exchange equipment is mainly located in the flue gas duct from the air preheater outlet to the dust collector inlet, absorbing heat from the tail flue gas through condensate. Some equipment also incorporates new technologies such as heat pump systems and molten salt energy storage to achieve efficient waste heat utilization. However, such heat exchange equipment operates in a complex and harsh environment for extended periods, and the flue gas contains… , , Corrosive agents, combined with the acidic medium formed by condensate, can easily cause severe corrosion to the equipment surface. At the same time, the dust generated during equipment operation will accelerate the corrosion process, leading to a shortened service life of the equipment, a decrease in waste heat utilization efficiency, increased equipment maintenance costs, and safety hazards.

[0003] However, the existing corrosion monitoring and protection technologies for waste heat recovery equipment in the tail flue gas ducts of coal-fired boilers still have many shortcomings, as detailed below: 1. Poor monitoring specificity and weak data correlation: Existing monitoring methods mostly use single indicators and do not take into account the actual operating conditions of the equipment (such as condensate water quality, flue gas parameters, and the operating status of heat pump / molten salt energy storage systems). They cannot accurately reflect the corrosion mechanism, and the monitoring data is disconnected from the protective measures, making it difficult to guide targeted protection.

[0004] 2. Poor compatibility between protective materials and processes: The selection of existing protective materials does not take into account the type of corrosion factors and operating conditions of the equipment, and the construction process is not matched with the operating rhythm of the waste heat utilization system, resulting in the protective layer being prone to peeling off and damage, and the protective life being short. Summary of the Invention

[0005] The present invention aims to solve at least one of the technical problems existing in the prior art, and to provide a new technical solution for corrosion monitoring and protection of waste heat exchange equipment for flue gas in boiler tail flue.

[0006] According to a first aspect of the present invention, a method for corrosion monitoring and protection of waste heat exchange equipment for flue gas in the tail section of a boiler is provided, comprising the following specific steps: S1 collects operating parameters of flue gas, condensate and heat pump / molten salt energy storage system, identifies corrosion factors, combines flow field simulation to predict and output corrosion level and easily corroded points, and constructs a distributed corrosion monitoring system accordingly. S2, based on the corrosion level and easily corroded points output by S1, initially selects and optimizes the layout of monitoring points, and at the same time starts the distributed corrosion monitoring system to collect multi-dimensional data in real time. After screening, a standardized monitoring data ledger is output. S3 processes the standardized monitoring data ledger output by S2, analyzes corrosion trends and provides graded early warnings. At the same time, it selects corrosion-resistant materials based on the dominant corrosion type according to the risk level, and designs suitable construction technology and construction process. S4, based on the construction technology and process output by S3, implements on-site protection and restores monitoring during the window period, then sets verification indicators to collect data after protection, compares and verifies the protection effect, and outputs an evaluation report; S5, after the protection effect is verified in S4, regularly inspects the monitoring equipment and protective layer, reviews the full-cycle monitoring and protection data, optimizes the monitoring strategy and protection plan, and forms an iterative update mechanism.

[0007] As a preferred embodiment of the corrosion monitoring and protection method for waste heat exchange equipment of boiler tail flue gas according to the present invention, the specific steps of S1 are as follows: S11, Operating condition survey and corrosion factor analysis: Collect operating parameters of flue gas, condensate and heat pump / molten salt energy storage system, identify core corrosion factors, and combine flow field simulation to predict the corrosion level of each part of the equipment and mark key points, output corrosion level and easily corroded points. S12, Corrosion Monitoring System Design: Based on the corrosion level and easily corroded locations output by S11, determine multi-dimensional monitoring indicators, select suitable monitoring equipment, and build a distributed corrosion monitoring system.

[0008] As a preferred embodiment of the corrosion monitoring and protection method for waste heat exchange equipment of boiler tail flue gas according to the present invention, the specific steps of S11 are as follows: S111, Operating Condition Data Acquisition: Conduct a comprehensive survey of the section from the air preheater outlet to the dust collector inlet of the tail flue of the coal-fired boiler, collect flue gas parameters, condensate water quality parameters, and operating parameters of the heat pump system and molten salt energy storage system, and simultaneously record the equipment installation location, structural dimensions and operating load, and output the operating condition parameter ledger. S112, Factor Identification: Based on the operating parameter ledger output by S111, identify the concentration and distribution pattern of core corrosion factors in flue gas, analyze the corrosiveness of condensate, and output corrosion factors and dominant corrosion types. S113, Corrosion Level Prediction: Based on the corrosion factors and dominant corrosion types output by S112, combined with industry corrosion level standards, CFD fluid dynamics simulation is used to analyze the flow field fluctuations in the flue, predict the corrosion level of different parts of the equipment, mark the key corrosion-prone points, and output the corrosion level and corrosion-prone points. The specific steps of S12 are as follows: S121, Indicator Determination: Based on the corrosion level and easily corroded locations output by S113, determine the targeted monitoring indicators and output each monitoring indicator. S122, Equipment Selection: Based on the monitoring indicators output by S121 and combined with the operating parameters, select monitoring equipment suitable for the high temperature, high dust, and strong corrosion environment of the flue. S123, Architecture Setup: Connect the monitoring equipment selected in S122 with the data acquisition module, wireless transmission module, and data processing center to build a distributed corrosion monitoring system. At the same time, design an early warning module to automatically issue audible and visual warnings when the monitoring indicators reach the warning threshold.

[0009] As a preferred embodiment of the corrosion monitoring and protection method for waste heat exchange equipment of boiler tail flue gas according to the present invention, the specific steps of S2 are as follows: S21, Optimization of monitoring point layout: Based on the corrosion level and easily corroded points output by S1, combined with the working condition parameter ledger, the monitoring points are initially selected, the point layout density is verified and adjusted, the monitoring equipment is fixed and the interface sealing protection is completed. S22, Real-time Corrosion Monitoring Implementation: Start the distributed corrosion monitoring system built in S1, debug and calibrate each monitoring device, collect multi-dimensional data at the set frequency, filter valid data, and output a standardized monitoring data ledger.

[0010] As a preferred embodiment of the corrosion monitoring and protection method for waste heat exchange equipment of boiler tail flue gas according to the present invention, the specific steps of S21 are as follows: S211, Initial Selection of Monitoring Points: Based on the corrosion level and easily corroded points output by S1, and in conjunction with the operating condition parameter log, initial selection of monitoring points is made. S212, Monitoring Point Verification: Based on the monitoring points initially selected in S211, the monitoring effectiveness of each point is verified through simulation calculations, the density of the monitoring point layout is adjusted, and the final monitoring points are output. S213, Fixed Location: Based on the final monitoring location output by S212, the monitoring equipment is fixed at the corresponding location, and the equipment interface is sealed with high-temperature and corrosion-resistant sealing materials. The specific steps of S22 are as follows: S221, Equipment Commissioning: Start the distributed corrosion monitoring system built in S1 and commission each monitoring device; S222, Data Acquisition: After the equipment commissioning is completed in S221, the data of each point is collected in real time through the monitoring equipment in combination with the preset monitoring frequency, and the operating parameters of the heat pump system and molten salt energy storage system are recorded simultaneously. All data is transmitted to the data processing center in real time and a continuous monitoring dataset is output. S223, Data Filtering: Denoise the continuous monitoring dataset output by S222, label the data acquisition time and corresponding operating parameters, and output a standardized monitoring data ledger.

[0011] As a preferred embodiment of the corrosion monitoring and protection method for waste heat exchange equipment of boiler tail flue gas according to the present invention, the specific steps of S3 are as follows: S31, Corrosion Data Processing and Analysis: The standardized monitoring data ledger output by S2 is uniformly converted and processed, and the corrosion development trend is analyzed in combination with the distribution law of corrosion factors. The corrosion risk of equipment is classified and warned, and the corrosion risk warning results are output. S32, Targeted Protection Solution Development: Based on the corrosion risk warning results output by S31, determine the protection requirements for different parts, select protective materials according to the dominant corrosion type, and design suitable construction technology and construction process.

[0012] As a preferred embodiment of the corrosion monitoring and protection method for waste heat exchange equipment of boiler tail flue gas according to the present invention, the specific steps of S31 are as follows: S311, Data Standardization: Based on the standardized monitoring data ledger output by S2, the corrosion rate data is standardized and converted using a power function model, and the converted standardized monitoring data ledger is output. S312, Trend Analysis: Based on the standardized monitoring data ledger output by S311, combined with the distribution law of corrosion factors, the corrosion rate is analyzed to change with time, flue gas parameters, condensate water quality, and heat pump / molten salt energy storage system operating parameters, and the corrosion trend analysis results are output. S313, Risk Warning: Based on the corrosion trend analysis results output by S312, combined with the warning threshold, the corrosion risk of the equipment is classified and warned, and the risk points and possible equipment failures are marked, and the corrosion risk warning results are output. The specific steps of S32 are as follows: S321, Determining Requirements: Based on the corrosion risk warning results output by S313, and combined with the corrosion level, determine the protection requirements for points with different corrosion levels. At the same time, combined with the operation rhythm of the heat pump system and molten salt energy storage system, determine the protection construction time window and output the protection requirements. S322, Material Selection: Based on the protection requirements output by S321 and combined with the dominant corrosion type, select suitable corrosion-resistant materials; S323, Process Design: Based on the corrosion-resistant materials selected in S322 and combined with protection requirements, a targeted protection construction process is designed, along with the construction flow.

[0013] As a preferred embodiment of the corrosion monitoring and protection method for waste heat exchange equipment of boiler tail flue gas according to the present invention, the specific steps of S4 are as follows: S41, On-site implementation of the protection plan: Complete the construction preparation work according to the construction technology and process designed in S3, and carry out on-site protection construction within the construction time window, clean up the site and restore the operation of monitoring equipment; S42, Protection Effectiveness Verification: After the protection implementation is completed in S41, protection effectiveness verification indicators are set, the original monitoring system is used to collect data after protection, the effectiveness is evaluated by comparing with the verification standards, and an evaluation report is output.

[0014] As a preferred embodiment of the corrosion monitoring and protection method for waste heat exchange equipment of boiler tail flue gas according to the present invention, the specific steps of S41 are as follows: S411, Construction Preparation: Based on the construction technology and process designed in S3, clean the dust and corrosion products on the monitoring points and the surface of the surrounding equipment, grind and remove rust from the equipment surface, and prepare construction tools, protective materials and safety protection facilities, and provide professional training to the construction personnel. S412, On-site construction: After completing the construction preparation in S411, within the protection construction time window, carry out protection construction on points with different corrosion levels according to the construction process. During the construction process, monitor the construction quality in real time and correct construction deviations in a timely manner. S413, Construction Cleanup: After the construction in S412 is completed, clean up the construction waste and dust at the construction site, check the sealing of the equipment surface and interfaces, dismantle the temporary construction facilities, restore the normal operation of the monitoring equipment, and record the construction parameters, construction location and construction time at the same time to form a construction ledger. The specific steps of S42 are as follows: S421, Indicator Setting: After the protection implementation is completed in S413, based on the standardized monitoring data ledger output in S2, set the verification indicators after protection and clarify the verification standards. S422, Effectiveness Testing: Based on the verification indicators set in S421, start the monitoring equipment to monitor the protected points, collect verification indicator data, compare it with the set verification indicators, and at the same time detect the changes in condensate water quality and flue gas corrosion factor concentration to evaluate the effectiveness of the protection plan and output an evaluation report. S423, Effectiveness Evaluation: Based on the evaluation report output by S422, the protective effect is evaluated in a graded manner. If the test indicators meet the standards, the protection is deemed effective and a protective effect evaluation report is generated. If the test indicators do not meet the standards, the reasons for the failure are analyzed, and the process is returned to S3 to adjust the protective plan and re-implement the protective construction.

[0015] As a preferred embodiment of the corrosion monitoring and protection method for waste heat exchange equipment of boiler tail flue gas according to the present invention, the specific steps of S5 are as follows: S51, Regular Inspection: Conduct inspections of monitoring equipment and protective layers at a preset frequency, record the inspection results, and output the inspection log. S52, Data Review: Regularly review the standardized monitoring data logs output by S2, the evaluation reports output by S4, and the inspection logs output by S51 to analyze the corrosion development trend and the changing pattern of the protection effect. Combine the adjustment of the operating parameters of the heat pump system and the molten salt energy storage system to output the data review results. S53, Solution Optimization: Based on the data review results output by S52, optimize the layout of monitoring points, monitoring frequency and early warning threshold, adjust the selection of protective materials and construction technology, adapt to changes in working conditions and corrosion development patterns, and form an optimized corrosion monitoring and protection solution.

[0016] One technical advantage of this invention is that: 1. By integrating multi-dimensional operating parameters of flue gas, condensate, and heat pump / molten salt energy storage systems, multi-corrosion factor linkage monitoring can be carried out, which can achieve accurate source tracing of corrosion types and enable protective measures to directly match the root cause of corrosion. 2. By combining CFD flow field simulation with corrosion level prediction, monitoring points can be deployed in a differentiated manner, achieving full coverage of key easily corroded areas, eliminating redundant monitoring, and balancing monitoring accuracy with cost control. 3. By matching the protective material with the dominant corrosion type and combining the design and construction process with the operating window of the waste heat system, the protective layer can be highly adapted to the equipment operating conditions, thus avoiding construction interference with the normal operation of the system. Attached Figure Description

[0017] Figure 1 This is a schematic flowchart illustrating a corrosion monitoring and protection method for a waste heat exchanger for flue gas in a boiler tail flue, according to an embodiment of the present invention. Detailed Implementation

[0018] Various exemplary embodiments of the present application will now be described in detail with reference to the accompanying drawings. It should be noted that, unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of the present application.

[0019] The embodiments of this application will now be described in detail. Examples of these embodiments are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0020] See Figure 1 This invention provides a method for corrosion monitoring and protection of waste heat exchange equipment for flue gas in boiler tail flue, comprising the following specific steps: S1, Operating condition survey and corrosion factor analysis: Collect operating parameters of flue gas, condensate and heat pump / molten salt energy storage system, identify core corrosion factors, and combine flow field simulation to predict the corrosion level of each part of the equipment and mark key points, output corrosion level and easily corroded points. Operating condition data collection: A comprehensive survey was conducted on the section of the flue gas duct from the air preheater outlet to the dust collector inlet of the coal-fired boiler. Flue gas parameters such as temperature, pressure, and flow velocity were collected, along with the pH value and water composition (including Cl- content) of the condensate. - SO4 2- Water quality parameters such as heat pump inlet and outlet temperatures and molten salt circulation rate are recorded, along with the operating parameters of the heat pump system and molten salt energy storage system. The equipment installation location, structural dimensions and operating load are recorded simultaneously, and the operating condition parameter ledger is output. Factor identification: Based on the operating parameter ledger, ion chromatography, spectral analysis, and other methods are used to identify factors in flue gas. , , The concentration and distribution patterns of core corrosion factors are analyzed, the corrosiveness of condensate is determined, the correlation between corrosion factors and equipment corrosion is clarified, the dominant corrosion type (such as acid corrosion and chloride ion corrosion) is identified, and the corrosion factors and dominant corrosion types are output. Corrosion Level Prediction: Based on corrosion factors and dominant corrosion types, combined with industry corrosion level standards, CFD fluid dynamics simulation is used to analyze the flow field fluctuations in the flue, predict the corrosion level (slight, moderate, severe) of different parts of the equipment (straight pipe sections, elbows, heat exchange tubes, and interfaces), and mark the key corrosion-prone points to provide a basis for subsequent monitoring and protection, outputting the corrosion level and easily corroded points.

[0021] S2, Corrosion Monitoring System Design: Based on the corrosion level and easily corroded locations, determine multi-dimensional monitoring indicators, select suitable monitoring equipment, and build a distributed corrosion monitoring system; Indicator determination: Based on the corrosion level and easily corroded locations, targeted monitoring indicators are determined, including equipment surface corrosion rate, corrosion layer thickness, coating integrity, as well as auxiliary monitoring indicators such as the concentration of corrosion factors in flue gas, changes in condensate water quality, and acid dew point temperature, and each monitoring indicator is output. Equipment selection: Based on various monitoring indicators and combined with operating parameters, select monitoring equipment suitable for the high temperature, high dust and strong corrosion environment of the flue, including corrosion sensors (using high and low frequency AC excitation mode, which can simultaneously monitor internal corrosion and external cracks), flue gas composition analyzers, water quality testers, acid dew point meters, etc., to ensure the measurement accuracy and stability of the monitoring equipment, and match the operating parameters of large-scale flue gas waste heat utilization equipment. Architecture Setup: Connect the selected monitoring equipment with the data acquisition module, wireless transmission module, and data processing center to build a distributed corrosion monitoring system, enabling real-time acquisition, transmission, and storage of monitoring data. At the same time, design an early warning module to automatically issue audible and visual warnings when the monitoring indicators reach the warning threshold, ensuring that the monitoring data can be accessed in real time.

[0022] S3, Optimization of monitoring point layout: Based on corrosion level and easily corroded points, combined with the working condition parameter ledger, the monitoring points are initially selected, the point layout density is verified and adjusted, the monitoring equipment is fixed and the interface sealing protection is completed. Preliminary selection of monitoring points: Based on the corrosion level and easily corroded points, and in conjunction with the operating condition parameter log, the monitoring points are initially selected, and priority is given to placing them in easily corroded parts such as flue bends, the bottom of heat exchange tubes, and condensate interfaces. At the same time, a small number of control points are placed in the straight pipe sections to ensure that the monitoring points cover all corrosion risk areas of the equipment. Location verification: Based on the initially selected monitoring locations, the monitoring effectiveness of each location is verified through simulation calculation (combined with the flue gas flow field fluctuation law), monitoring blind spots and data redundancy are eliminated, the density of location layout is adjusted to ensure that no key corrosion areas are missed, non-critical areas are simplified in layout, monitoring costs are reduced, and the final monitoring locations are output. Location Fixing: Based on the final monitoring locations, the monitoring equipment is fixed at the corresponding locations, and the equipment interfaces are sealed with high-temperature and corrosion-resistant sealing materials to ensure dust and vibration protection, prevent interference from flue gas dust and vibration, and ensure stable operation of the monitoring equipment.

[0023] S4, Real-time Corrosion Monitoring Implementation: Start the completed distributed corrosion monitoring system, debug and calibrate each monitoring device, collect multi-dimensional data at the set frequency, filter valid data, and output a standardized monitoring data ledger; Equipment commissioning: Start the completed distributed corrosion monitoring system, commission each monitoring device, calibrate the measurement accuracy of corrosion sensors, water quality analyzers and other equipment, test the stability of data transmission, and ensure that the monitoring indicators are collected accurately, transmitted smoothly and that the early warning module responds normally. Data Acquisition: After the equipment commissioning is completed, the corrosion rate, corrosion factor concentration, condensate water quality, acid dew point temperature and other data at each point are collected in real time by the monitoring equipment in combination with the preset monitoring frequency. The operating parameters of the heat pump system and molten salt energy storage system are recorded at the same time. All data are transmitted to the data processing center in real time and a continuous monitoring dataset is output. Data filtering: The continuous monitoring dataset is denoised to remove abnormal data caused by equipment failure or sudden changes in operating conditions, retain valid data, and label the data collection time and corresponding operating parameters to output a standardized monitoring data ledger.

[0024] S5, Corrosion Data Processing and Analysis: Standardized monitoring data ledgers are uniformly converted and processed, and corrosion development trends are analyzed in combination with the distribution patterns of corrosion factors. Equipment corrosion risks are classified and warned, and corrosion risk warning results are output. Data standardization: Based on standardized monitoring data ledgers, the corrosion rate data is standardized and converted using a power function model, unifying data units and calculation standards, eliminating data differences between different monitoring equipment and different locations, facilitating comparative analysis, and outputting standardized monitoring data ledgers after conversion; Trend Analysis: Based on the standardized monitoring data ledger after conversion, and combined with the distribution pattern of corrosion factors, the trend of corrosion rate with time, flue gas parameters, condensate water quality, and operating parameters of heat pump / molten salt energy storage system is analyzed to clarify the corrosion development law, predict the corrosion development direction, and output the corrosion trend analysis results. Risk Warning: Based on corrosion trend analysis results and warning thresholds, the corrosion risk of equipment is classified and warned in stages. A warning is issued for mild corrosion, a key warning is issued for moderate corrosion, and an emergency warning is issued for severe corrosion. At the same time, the risk points and possible equipment failures are marked, providing an accurate basis for the formulation of protection plans and outputting corrosion risk warning results.

[0025] S6, Targeted protection solution development: Based on corrosion risk warning results, determine the protection requirements of different parts, select protective materials according to the dominant corrosion type, and design suitable construction technology and construction process; Demand Determination: Based on the corrosion risk warning results and the corrosion level, determine the protection requirements for different corrosion level locations. For mild corrosion, focus on the maintenance of the protective layer; for moderate corrosion, focus on the coating upgrade; and for severe corrosion, focus on material replacement or structural optimization. At the same time, combine the operation rhythm of the heat pump system and the molten salt energy storage system to determine the protection construction time window and output the protection requirements. Material selection: Based on protection requirements and the dominant corrosion type, select appropriate corrosion-resistant materials. For mild corrosion, use glass flake coating; for moderate corrosion, use polytetrafluoroethylene coating; and for severe corrosion, use 316L stainless steel or titanium alloy composite plate. Ensure that the materials are resistant to flue gas corrosion and condensate erosion, and are compatible with the equipment operating conditions and waste heat recovery system. Process Design: Based on the selected corrosion-resistant materials and combined with protection requirements, a targeted protection construction process was designed. The coating was applied using a high-pressure spraying process, and the material replacement was carried out using a cutting and welding process. At the same time, the construction process was designed to avoid the peak operating times of the heat pump system and the molten salt energy storage system, ensuring that the construction does not affect the normal operation of the waste heat utilization system and that the construction quality meets the standards.

[0026] S7, On-site implementation of protection plan: Complete the construction preparation work according to the designed construction technology and process, carry out on-site protection construction within the construction time window, clean up the site and restore the operation of monitoring equipment; Construction preparation: Based on the designed construction technology and process, clean the dust and corrosion products on the monitoring points and surrounding equipment surfaces, grind and remove rust from the equipment surfaces to ensure that the surfaces are flat and free of oil stains, and prepare construction tools, protective materials and safety protection facilities, and provide professional training to construction personnel. On-site construction: After completing the construction preparation, within the protection construction time window, carry out protection construction on points with different corrosion levels according to the construction process. Ensure uniform coating thickness during coating construction, ensure interface sealing and firm connection during material replacement, monitor construction quality in real time during construction, and correct construction deviations in a timely manner. Construction cleanup: After construction is completed, clean up construction waste and dust at the construction site, check the sealing of equipment surfaces and interfaces, dismantle temporary construction facilities, restore the normal operation of monitoring equipment, and record construction parameters, construction locations and construction time simultaneously to form a construction ledger.

[0027] S8, Protection Effect Verification: After the protection implementation is completed, protection effect verification indicators are set, the original monitoring system is used to collect data after protection, the effect is evaluated by comparing with the verification standard, and an evaluation report is output. Indicator setting: After the protection is implemented, based on the standardized monitoring data ledger, set verification indicators such as corrosion rate, coating integrity, and corrosion factor isolation effect after protection, and clarify the verification standards (such as corrosion rate reduction of more than 80% after protection and no damage to the coating) to ensure that the verification indicators are scientific and quantifiable. Effectiveness testing: Based on the set verification indicators, the monitoring equipment is activated to monitor the protected points, collect verification indicator data such as corrosion rate and coating integrity, and compare them with the set verification indicators. At the same time, the changes in condensate water quality and flue gas corrosion factor concentration are detected to evaluate the effectiveness of the protection plan and output an evaluation report. Effectiveness evaluation: Based on the output evaluation report, the protective effect is graded and evaluated. If the test indicators meet the standards, the protection is deemed effective and a protective effect evaluation report is generated. If the test indicators do not meet the standards, the reasons for the failure to meet the standards are analyzed (such as improper material selection or defects in construction process), and the protection plan is adjusted and the protection construction is re-implemented until the standards are met.

[0028] S9, Post-maintenance and optimization: After the protection effect is verified, regularly inspect the monitoring equipment and protection layer, review the full cycle monitoring and protection data, optimize the monitoring strategy and protection plan, and form an iterative update mechanism; Regular inspections: Conduct inspections of the monitoring equipment and protective layer at a preset frequency (once a week), check the operating status of the monitoring equipment and the integrity of the protective layer, clean dust from the surface of the equipment, promptly address minor damage or loosening, record the inspection results, and output an inspection log. Data review: Regularly (monthly) review the standardized monitoring data ledger, assessment report and inspection ledger, analyze the corrosion development trend and the change law of protection effect, and combine the adjustment of the operating parameters of the heat pump system and molten salt energy storage system to identify the shortcomings of the protection plan and output the data review results. Solution optimization: Based on the data review results, the layout of monitoring points, monitoring frequency and early warning thresholds are optimized, the selection of protective materials and construction technology are adjusted, and the changes in working conditions and corrosion development patterns are adapted to form an optimized corrosion monitoring and protection solution, so as to achieve corrosion control throughout the entire life cycle of the equipment and ensure the long-term stable operation of the waste heat utilization equipment.

[0029] It is understood that the above embodiments are merely exemplary implementations used to illustrate the principles of the present invention, and the present invention is not limited thereto. For those skilled in the art, various modifications and improvements can be made without departing from the spirit and essence of the present invention, and these modifications and improvements are also considered to be within the scope of protection of the present invention.

Claims

1. A method for corrosion monitoring and protection of waste heat exchange equipment for flue gas in boiler tail flue, characterized in that, The specific steps are as follows: S1 collects operating parameters of flue gas, condensate and heat pump / molten salt energy storage system, identifies corrosion factors, combines flow field simulation to predict and output corrosion level and easily corroded points, and constructs a distributed corrosion monitoring system accordingly. S2, based on the corrosion level and easily corroded points output by S1, initially selects and optimizes the layout of monitoring points, and at the same time starts the distributed corrosion monitoring system to collect multi-dimensional data in real time. After screening, a standardized monitoring data ledger is output. S3 processes the standardized monitoring data ledger output by S2, analyzes corrosion trends and provides graded early warnings. At the same time, it selects corrosion-resistant materials based on the dominant corrosion type according to the risk level, and designs suitable construction technology and construction process. S4, based on the construction technology and process output by S3, implements on-site protection and restores monitoring during the window period, then sets verification indicators to collect data after protection, compares and verifies the protection effect, and outputs an evaluation report; S5, after the protection effect is verified in S4, regularly inspects the monitoring equipment and protective layer, reviews the full-cycle monitoring and protection data, optimizes the monitoring strategy and protection plan, and forms an iterative update mechanism.

2. The corrosion monitoring and protection method for waste heat exchange equipment in boiler tail flue gas according to claim 1, characterized in that, The specific steps of S1 are as follows: S11, Operating condition survey and corrosion factor analysis: Collect operating parameters of flue gas, condensate and heat pump / molten salt energy storage system, identify core corrosion factors, and combine flow field simulation to predict the corrosion level of each part of the equipment and mark key points, output corrosion level and easily corroded points. S12, Corrosion Monitoring System Design: Based on the corrosion level and easily corroded locations output by S11, determine multi-dimensional monitoring indicators, select suitable monitoring equipment, and build a distributed corrosion monitoring system.

3. The corrosion monitoring and protection method for waste heat exchange equipment in boiler tail flue gas according to claim 2, characterized in that, The specific steps of S11 are as follows: S111, Operating Condition Data Acquisition: Conduct a comprehensive survey of the section from the air preheater outlet to the dust collector inlet of the tail flue of the coal-fired boiler, collect flue gas parameters, condensate water quality parameters, and operating parameters of the heat pump system and molten salt energy storage system, and simultaneously record the equipment installation location, structural dimensions and operating load, and output the operating condition parameter ledger. S112, Factor Identification: Based on the operating parameter ledger output by S111, identify the concentration and distribution pattern of core corrosion factors in flue gas, analyze the corrosiveness of condensate, and output corrosion factors and dominant corrosion types. S113, Corrosion Level Prediction: Based on the corrosion factors and dominant corrosion types output by S112, combined with industry corrosion level standards, CFD fluid dynamics simulation is used to analyze the flow field fluctuations in the flue, predict the corrosion level of different parts of the equipment, mark the key points that are prone to corrosion, and output the corrosion level and the points that are prone to corrosion. The specific steps of S12 are as follows: S121, Indicator Determination: Based on the corrosion level and easily corroded locations output by S113, determine the targeted monitoring indicators and output each monitoring indicator. S122, Equipment Selection: Based on the monitoring indicators output by S121 and combined with the operating parameters, select monitoring equipment suitable for the high temperature, high dust, and strong corrosion environment of the flue. S123, Architecture Setup: Connect the monitoring equipment selected in S122 with the data acquisition module, wireless transmission module, and data processing center to build a distributed corrosion monitoring system. At the same time, design an early warning module to automatically issue audible and visual warnings when the monitoring indicators reach the warning threshold.

4. The corrosion monitoring and protection method for waste heat exchange equipment in boiler tail flue gas according to claim 1, characterized in that, The specific steps of S2 are as follows: S21, Optimization of monitoring point layout: Based on the corrosion level and easily corroded points output by S1, combined with the working condition parameter ledger, the monitoring points are initially selected, the point layout density is verified and adjusted, the monitoring equipment is fixed and the interface sealing protection is completed. S22, Real-time Corrosion Monitoring Implementation: Start the distributed corrosion monitoring system built in S1, debug and calibrate each monitoring device, collect multi-dimensional data at the set frequency, filter valid data, and output a standardized monitoring data ledger.

5. The corrosion monitoring and protection method for waste heat exchange equipment in boiler tail flue gas according to claim 4, characterized in that, The specific steps of S21 are as follows: S211, Initial Selection of Monitoring Points: Based on the corrosion level and easily corroded points output by S1, and in conjunction with the operating condition parameter log, initial selection of monitoring points is made. S212, Monitoring Point Verification: Based on the monitoring points initially selected in S211, the monitoring effectiveness of each point is verified through simulation calculations, the density of the monitoring point layout is adjusted, and the final monitoring points are output. S213, Fixed Location: Based on the final monitoring location output by S212, the monitoring equipment is fixed at the corresponding location, and the equipment interface is sealed with high-temperature and corrosion-resistant sealing materials. The specific steps of S22 are as follows: S221, Equipment Commissioning: Start the distributed corrosion monitoring system built in S1 and commission each monitoring device; S222, Data Acquisition: After the equipment commissioning is completed in S221, the data of each point is collected in real time through the monitoring equipment in combination with the preset monitoring frequency, and the operating parameters of the heat pump system and molten salt energy storage system are recorded simultaneously. All data is transmitted to the data processing center in real time and a continuous monitoring dataset is output. S223, Data Filtering: Denoise the continuous monitoring dataset output by S222, label the data acquisition time and corresponding operating parameters, and output a standardized monitoring data ledger.

6. The corrosion monitoring and protection method for waste heat exchange equipment in boiler tail flue gas according to claim 1, characterized in that, The specific steps of S3 are as follows: S31, Corrosion Data Processing and Analysis: The standardized monitoring data ledger output by S2 is uniformly converted and processed, and the corrosion development trend is analyzed in combination with the distribution law of corrosion factors. The corrosion risk of equipment is graded and early warning is given, and the corrosion risk early warning results are output. S32, Targeted Protection Solution Development: Based on the corrosion risk warning results output by S31, determine the protection requirements of different parts, select protective materials according to the dominant corrosion type, and design suitable construction technology and construction process.

7. The corrosion monitoring and protection method for waste heat exchange equipment in boiler tail flue gas according to claim 6, characterized in that, The specific steps of S31 are as follows: S311, Data Standardization: Based on the standardized monitoring data ledger output by S2, the corrosion rate data is standardized and converted using a power function model, and the converted standardized monitoring data ledger is output. S312, Trend Analysis: Based on the standardized monitoring data ledger output by S311, combined with the distribution law of corrosion factors, the corrosion rate is analyzed to change with time, flue gas parameters, condensate water quality, and operating parameters of heat pump / molten salt energy storage system, and the corrosion trend analysis results are output. S313, Risk Warning: Based on the corrosion trend analysis results output by S312, combined with the warning threshold, the corrosion risk of the equipment is classified and warned, and the risk points and possible equipment failures are marked, and the corrosion risk warning results are output. The specific steps of S32 are as follows: S321, Determining Requirements: Based on the corrosion risk warning results output by S313, and combined with the corrosion level, determine the protection requirements for points with different corrosion levels. At the same time, combined with the operation rhythm of the heat pump system and molten salt energy storage system, determine the protection construction time window and output the protection requirements. S322, Material Selection: Based on the protection requirements output by S321 and combined with the dominant corrosion type, select suitable corrosion-resistant materials; S323, Process Design: Based on the corrosion-resistant materials selected in S322 and combined with protection requirements, a targeted protection construction process is designed, along with the construction flow.

8. The corrosion monitoring and protection method for waste heat exchange equipment in boiler tail flue gas according to claim 1, characterized in that, The specific steps of S4 are as follows: S41, On-site implementation of the protection plan: Complete the construction preparation work according to the construction technology and process designed in S3, and carry out on-site protection construction within the construction time window, clean up the site and restore the operation of monitoring equipment; S42, Protection Effectiveness Verification: After the protection implementation is completed in S41, protection effectiveness verification indicators are set, the original monitoring system is used to collect data after protection, the effectiveness is evaluated by comparing with the verification standards, and an evaluation report is output.

9. A method for corrosion monitoring and protection of waste heat exchange equipment for boiler tail flue gas according to claim 8, characterized in that, The specific steps of S41 are as follows: S411, Construction Preparation: Based on the construction technology and process designed in S3, clean the dust and corrosion products on the monitoring points and the surface of the surrounding equipment, grind and remove rust from the equipment surface, and prepare construction tools, protective materials and safety protection facilities, and provide professional training to the construction personnel. S412, On-site construction: After completing the construction preparation in S411, within the protection construction time window, carry out protection construction on points with different corrosion levels according to the construction process. During the construction process, monitor the construction quality in real time and correct construction deviations in a timely manner. S413, Construction Cleanup: After the construction in S412 is completed, clean up the construction waste and dust at the construction site, check the sealing of the equipment surface and interfaces, dismantle the temporary construction facilities, restore the normal operation of the monitoring equipment, and record the construction parameters, construction location and construction time at the same time to form a construction ledger. The specific steps of S42 are as follows: S421, Indicator Setting: After the protection implementation is completed in S413, based on the standardized monitoring data ledger output in S2, set the verification indicators after protection and clarify the verification standards. S422, Effectiveness Testing: Based on the verification indicators set in S421, start the monitoring equipment to monitor the protected points, collect verification indicator data, compare it with the set verification indicators, and at the same time detect the changes in condensate water quality and flue gas corrosion factor concentration to evaluate the effectiveness of the protection plan and output an evaluation report. S423, Effectiveness Evaluation: Based on the evaluation report output by S422, the protective effect is evaluated in a graded manner. If the test indicators meet the standards, the protection is deemed effective and a protective effect evaluation report is generated. If the test indicators do not meet the standards, the reasons for the failure are analyzed, and the process is returned to S3 to adjust the protective plan and re-implement the protective construction.

10. The corrosion monitoring and protection method for waste heat exchange equipment in boiler tail flue gas according to claim 1, characterized in that, The specific steps of S5 are as follows: S51, Regular Inspection: Conduct inspections of monitoring equipment and protective layers at a preset frequency, record the inspection results, and output the inspection log. S52, Data Review: Regularly review the standardized monitoring data logs output by S2, the evaluation reports output by S4, and the inspection logs output by S51 to analyze the corrosion development trend and the changing pattern of the protection effect. Combine the adjustment of the operating parameters of the heat pump system and the molten salt energy storage system to output the data review results. S53, Solution Optimization: Based on the data review results output by S52, optimize the layout of monitoring points, monitoring frequency and early warning threshold, adjust the selection of protective materials and construction technology, adapt to changes in working conditions and corrosion development patterns, and form an optimized corrosion monitoring and protection solution.

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