Anti-explosion control method, device and equipment for heating surface of boiler in thermal power plant and storage medium

Abstract

This invention belongs to the field of safety monitoring technology for thermal power plants, and discloses a method, device, equipment, and storage medium for explosion-proof control of boiler heating surfaces in thermal power plants. The method includes: determining the basic wall temperature distribution based on the flue gas side heat absorption deviation, steam side flow deviation, and thermal deviation coefficient calculated from the structural parameters and operating conditions of the boiler's high-temperature heating surface using a preset metal wall temperature calculation model; iteratively calculating the oxide film thickness distribution using an oxide film growth prediction model based on the basic wall temperature distribution; correcting the basic wall temperature distribution using the oxide film thickness distribution; assessing the remaining lifespan of the boiler heating surface based on the corrected metal wall temperature distribution combined with a high-temperature creep fracture life model; and performing explosion-proof control of the boiler heating surface based on its remaining lifespan. This method considers the dynamic influence of actual operating factors such as oxide film thermal resistance and thermal deviation on the wall temperature, improving the accuracy of remaining lifespan assessment and effectively controlling the explosion-proof performance of the heating surface.

Description

Technical Field

[0001] This invention relates to the field of safety monitoring technology for thermal power plants, and in particular to a method, device, equipment, and storage medium for explosion-proof control of the heating surface of a thermal power plant boiler. Background Technology

[0002] As the core power equipment of thermal power plants, boilers operate under high temperature, high pressure, and complex flue gas environments for extended periods, facing multiple failure risks such as oxide film growth, creep damage, and thermal deviation. Among these, high-temperature creep fracture is one of the main causes of tube rupture in heating surfaces: as operating time increases, the metal material gradually undergoes plastic deformation accumulation under continuous stress and high temperature, eventually leading to tube wall thinning, crack propagation, and even tube rupture, seriously threatening boiler safety and unit economy.

[0003] Current technologies for assessing the remaining life of heated surfaces primarily rely on the traditional Larson-Miller parameter (LMP) model, which calculates the creep rupture life of materials using metal wall temperature and stress. This model is based on idealized assumptions, treating the wall temperature as uniformly distributed and neglecting the time-varying effects of oxide film growth on heat transfer characteristics. This leads to discrepancies between the estimated remaining life under complex operating conditions and the actual situation. Furthermore, existing technologies typically employ simplified assumptions about heat load uniformity, failing to establish a coupled calculation model between flue gas-side heat absorption deviation, steam-side flow deviation, and wall temperature distribution. This makes it difficult to accurately reflect the actual temperature state of each tube panel and each tube within the same panel, thus hindering precise and effective control of the heated surfaces.

[0004] The above content is only used to help understand the technical solution of the present invention and does not represent an admission that the above content is prior art. Summary of the Invention

[0005] The main objective of this invention is to provide a method, device, equipment, and storage medium for explosion-proof control of the heating surface of a thermal power plant boiler, aiming to solve the technical problem that leads to a large deviation between the remaining life assessment and the actual operating conditions, reducing the accuracy of the remaining life assessment and thus making it impossible to accurately and effectively control the heating surface.

[0006] To achieve the above objectives, the present invention provides a method for explosion-proof control of the heating surface of a thermal power plant boiler, comprising the following steps: Calculate the flue gas side heat absorption deviation, steam side flow deviation, and thermal deviation coefficient based on the boiler high-temperature heating surface structural parameters and operating conditions. The basic wall temperature distribution is determined using a preset metal wall temperature calculation model based on the heat absorption deviation on the flue gas side, the flow deviation on the steam side, and the thermal deviation coefficient. Based on the aforementioned basic wall temperature distribution, the oxide film thickness distribution is iteratively calculated using an oxide film growth prediction model. The basic wall temperature distribution is corrected using the oxide film thickness distribution to obtain the corrected metal wall temperature distribution; Based on the modified metal wall temperature distribution combined with the high-temperature creep fracture life model, the remaining life of the boiler heating surface is evaluated. Explosion-proof control of the boiler heating surface is implemented based on the remaining lifespan of the boiler heating surface.

[0007] In some embodiments, the calculation of flue gas side heat absorption deviation, steam side flow deviation, and heat deviation coefficient based on boiler high-temperature heating surface structural parameters and operating conditions includes: A thermal deviation calculation model is constructed based on the structural parameters of the boiler's high-temperature heating surface and operating conditions. The thermal deviation calculation model includes a flue gas side heat absorption deviation calculation model, a steam side flow rate deviation calculation model, and a thermal deviation coefficient calculation model. The flue gas side heat absorption deviation calculation model is used to calculate the heat load distribution along the width and height of the flue using a heat load unevenness coefficient model. The steam side flow rate deviation calculation model is used to calculate the flow rate distribution between panels and among the pipes in the same panel based on the header connection form, pipe group resistance coefficient, and header static pressure distribution model. The thermal deviation coefficient calculation model is used to combine the heat load unevenness coefficient and the flow rate unevenness coefficient to obtain the thermal deviation coefficient of each pipe panel and among the pipes in the same panel. The heat absorption deviation on the flue gas side, the flow rate deviation on the steam side, and the heat deviation coefficient are calculated using the aforementioned thermal deviation calculation model.

[0008] In some embodiments, the step of iteratively calculating the oxide film thickness distribution using an oxide film growth prediction model based on the baseline wall temperature distribution includes: The oxidation rate coefficient is determined based on the aforementioned basic wall temperature distribution; The oxide film thickness increment is determined based on the oxidation rate coefficient. The oxide film thickness distribution is obtained based on the initial oxide film thickness and the oxide film thickness increment.

[0009] In some embodiments, the correction of the basic wall temperature distribution using the oxide film thickness distribution includes: Obtain the working fluid temperature, the ratio of the inner and outer diameters of the heated surface, and the heat load limit; The correction temperature is determined by combining the working fluid temperature, the ratio of the inner and outer diameters of the heated surface, the heat load limit, the oxide film thickness distribution, and a preset coefficient, wherein the preset coefficient includes the working fluid heat transfer coefficient and the metal thermal conductivity. The outer wall temperature is determined based on the corrected temperature and the working fluid temperature, and the basic wall temperature distribution is corrected based on the outer wall temperature.

[0010] In some embodiments, assessing the remaining life of the boiler heating surface based on the modified metal wall temperature distribution combined with a high-temperature creep fracture life model includes: The outer wall temperature is determined based on the corrected metal wall temperature distribution; Determine the thermal stress on the heated surface; The fracture time is determined based on the thermal stress and the outer wall temperature. The remaining life of the boiler's heating surfaces is assessed based on the boiler's operating time and the fracture time.

[0011] In some embodiments, the explosion-proof control of the boiler heating surface based on its remaining lifespan includes: The risk level is determined based on the remaining lifespan of the boiler's heating surfaces; Based on the risk level, a corresponding explosion-proof control strategy is implemented. The explosion-proof control strategy includes at least one of the following: reducing the burner swing angle, adjusting the secondary air distribution, adjusting the throttling ring, reducing the superheater outlet temperature, and increasing the steam flow rate of the tube panel. Based on the risk level, a corresponding early warning is triggered, which is used to remind the user to reduce the heat load or perform emergency maintenance.

[0012] Furthermore, to achieve the above objectives, the present invention also proposes an explosion-proof control device for the heating surface of a thermal power plant boiler, the explosion-proof control device for the heating surface of a thermal power plant boiler comprising: The processing module is used to calculate the flue gas side heat absorption deviation, steam side flow deviation, and thermal deviation coefficient based on the structural parameters of the boiler's high-temperature heating surface and operating conditions. The processing module is used to determine the basic wall temperature distribution based on the flue gas side heat absorption deviation, the steam side flow deviation, and the heat deviation coefficient using a preset metal wall temperature calculation model. The processing module is used to iteratively calculate the oxide film thickness distribution based on the basic wall temperature distribution using an oxide film growth prediction model. The processing module is used to correct the basic wall temperature distribution using the oxide film thickness distribution to obtain a corrected metal wall temperature distribution. The processing module is used to evaluate the remaining life of the boiler heating surface based on the corrected metal wall temperature distribution combined with the high-temperature creep fracture life model. The control module is used to perform explosion-proof control on the boiler heating surface based on the remaining lifespan of the boiler heating surface.

[0013] Furthermore, to achieve the above objectives, the present invention also proposes an explosion-proof control device for the heating surface of a thermal power plant boiler. The explosion-proof control device for the heating surface of a thermal power plant boiler includes: a memory, a processor, and an explosion-proof control program for the heating surface of a thermal power plant boiler stored in the memory and executable on the processor. The explosion-proof control program for the heating surface of a thermal power plant boiler is configured to implement the steps of the explosion-proof control method for the heating surface of a thermal power plant boiler as described above.

[0014] Furthermore, to achieve the above objectives, the present invention also proposes a storage medium storing an explosion-proof control program for the heating surface of a thermal power plant boiler. When the explosion-proof control program for the heating surface of a thermal power plant boiler is executed by a processor, it implements the steps of the explosion-proof control method for the heating surface of a thermal power plant boiler as described above.

[0015] This invention determines the basic wall temperature distribution by utilizing a pre-set metal wall temperature calculation model based on the flue gas side heat absorption deviation, steam side flow deviation, and thermal deviation coefficient calculated from the structural parameters and operating conditions of the boiler's high-temperature heating surface. Based on the basic wall temperature distribution, an oxide film growth prediction model iteratively calculates the oxide film thickness distribution. The basic wall temperature distribution is then corrected using the oxide film thickness distribution. Based on the corrected metal wall temperature distribution and a high-temperature creep fracture life model, the remaining lifespan of the boiler's heating surface is assessed. Finally, explosion-proof control of the boiler's heating surface is implemented based on its remaining lifespan. This method considers the dynamic influence of actual operating factors such as oxide film thermal resistance and thermal deviation on the wall temperature, improving the accuracy of remaining lifespan assessment and effectively controlling the explosion-proof performance of the heating surface. Attached Figure Description

[0016] Figure 1 This is a flowchart illustrating the first embodiment of the explosion-proof control method for the heating surface of a thermal power plant boiler according to the present invention. Figure 2 This is a structural block diagram of the first embodiment of the explosion-proof control device for the heating surface of a thermal power plant boiler according to the present invention.

[0017] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0018] It should be understood that the specific embodiments described herein are for illustrative purposes only and are not intended to limit the scope of the invention.

[0019] This invention provides a method for explosion-proof control of the heating surface of a thermal power plant boiler, referring to... Figure 1 , Figure 1 This is a flowchart illustrating the first embodiment of the explosion-proof control method for the heating surface of a thermal power plant boiler according to the present invention.

[0020] In this embodiment, the explosion-proof control method for the heating surface of a thermal power plant boiler includes the following steps: Step S10: Calculate the flue gas side heat absorption deviation, steam side flow deviation, and thermal deviation coefficient based on the boiler high-temperature heating surface structural parameters and operating conditions.

[0021] Step S20: Determine the basic wall temperature distribution based on the flue gas side heat absorption deviation, the steam side flow deviation, and the thermal deviation coefficient using a preset metal wall temperature calculation model.

[0022] In this embodiment, the executing entity is an explosion-proof control device for the heating surface of a thermal power plant boiler. This explosion-proof control device has functions such as data processing, data communication, and program execution. The explosion-proof control device for the heating surface of a thermal power plant boiler can be a computer terminal device or other network device, or other devices with similar functions. This embodiment does not limit the scope of the invention.

[0023] It should be noted that boilers, as the core power equipment in thermal power plants, operate their heating surfaces under high temperature, high pressure, and complex flue gas environments for extended periods, facing multiple failure risks such as oxide film growth, creep damage, and thermal deviation. High-temperature creep fracture is one of the main causes of heating surface tube rupture: as operating time increases, the metal material gradually undergoes cumulative plastic deformation under continuous stress and high temperature, eventually leading to tube wall thinning, crack propagation, and even tube rupture, seriously threatening boiler safety and unit economy. Current technologies for assessing the remaining life of heating surfaces mainly rely on the traditional Larson-Miller parameter (LMP) model, calculating the creep fracture life of the material through metal wall temperature and stress. This method does not fully consider the dynamic impact of actual operating factors such as oxide film thermal resistance and thermal deviation on wall temperature, resulting in a large deviation between the remaining life assessment and actual operating conditions, reducing the accuracy of the remaining life assessment and thus hindering precise and effective control of the heating surfaces.

[0024] To address the aforementioned technical issues, this embodiment utilizes a pre-defined metal wall temperature calculation model to determine the basic wall temperature distribution based on the flue gas side heat absorption deviation, steam side flow deviation, and thermal deviation coefficient calculated from the boiler's high-temperature heating surface structural parameters and operating conditions. Based on the basic wall temperature distribution, an oxide film growth prediction model iteratively calculates the oxide film thickness distribution. The basic wall temperature distribution is then corrected using the oxide film thickness distribution. Based on the corrected metal wall temperature distribution and a high-temperature creep fracture life model, the remaining lifespan of the boiler heating surface is assessed. Finally, explosion-proof control of the boiler heating surface is implemented based on its remaining lifespan. This approach considers the dynamic influence of actual operating factors such as oxide film thermal resistance and thermal deviation on the wall temperature, improving the accuracy of remaining lifespan assessment and effectively controlling the explosion-proof performance of the heating surface. Specifically, it can be implemented as follows.

[0025] In this specific implementation, it is necessary to first calculate the flue gas side heat absorption deviation, steam side flow deviation, and thermal deviation coefficient based on the boiler high-temperature heating surface structural parameters and operating conditions. The boiler high-temperature heating surface structural parameters include, for example, the number of tube panels, the number of tubes in the same panel, the tube diameter, and the wall thickness. Operating conditions include, for example, steam flow rate, inlet and outlet temperatures, pressure, and flue gas temperature.

[0026] Specifically, the process of calculating the flue gas side heat absorption deviation, steam side flow deviation, and thermal deviation coefficient based on the boiler high-temperature heating surface structural parameters and operating conditions involves constructing a thermal deviation calculation model based on the boiler high-temperature heating surface structural parameters and operating conditions; and using the thermal deviation calculation model to calculate the flue gas side heat absorption deviation, steam side flow deviation, and thermal deviation coefficient.

[0027] It should be noted that the thermal deviation calculation model includes a flue gas-side heat absorption deviation calculation model, a steam-side flow rate deviation calculation model, and a thermal deviation coefficient calculation model. The flue gas-side heat absorption deviation calculation model is used to calculate the heat load distribution along the width and height of the flue using a heat load unevenness coefficient model. The steam-side flow rate deviation calculation model is used to calculate the flow rate distribution between panels and within each panel based on the header connection type, pipe group resistance coefficient, and header static pressure distribution model. The thermal deviation coefficient calculation model combines the heat load unevenness coefficient and the flow rate unevenness coefficient to obtain the thermal deviation coefficient for each panel and each pipe within the same panel. The heat load unevenness coefficient model can be, for example, a unimodal or saddle-shaped distribution function. The header connection type can be, for example, U-shaped or Z-shaped. The thermal deviation coefficient is calculated as follows: thermal deviation coefficient for each panel and each pipe within the same panel φ = η_q × η_g, where η_q is the heat load unevenness coefficient and η_g is the flow rate unevenness coefficient. Basic wall temperature calculation: Based on heat load, flow distribution and working fluid / flue gas parameters, a metal wall temperature calculation model is adopted. It should be noted that the oxide film is not considered when calculating the inner wall temperature and outer wall temperature along the pipe length.

[0028] Through the above steps, the metal wall temperature (T_w,i) of each micro-element segment is calculated segment by segment, and finally the basic wall temperature distribution curve along the tube length is obtained (e.g., inlet segment T_w=540℃, middle segment T_w=580℃, outlet segment T_w=620℃). This distribution reflects the non-uniformity of the wall temperature on the heated surface due to thermal deviation when the correction factors such as oxide film and ash accumulation are not considered.

[0029] Step S30: Based on the basic wall temperature distribution, the oxide film thickness distribution is iteratively calculated using the oxide film growth prediction model.

[0030] In a specific implementation, the oxidation rate coefficient of the current iteration step can be determined based on the basic wall temperature distribution; The oxide film thickness increment for the current iteration step is determined based on the oxidation rate coefficient. The oxide film thickness of the current iteration step is obtained based on the oxide film thickness of the previous iteration step and the oxide film thickness increment of the current iteration step. Determine whether the difference between the oxide film thickness of the current iteration step and the oxide film thickness of the previous iteration step is less than a preset convergence threshold; If so, stop the iteration and use the oxide film thickness of the current iteration step as the oxide film thickness distribution; If not, update the base wall temperature distribution based on the oxide film thickness of the current iteration step, and return to the step of determining the oxidation rate coefficient based on the updated base wall temperature distribution.

[0031] For example: "Based on the basic wall temperature distribution, determine the oxidation rate coefficient k_p,i for the current iteration step; determine the oxide film thickness increment Δδ_x,i(n) = (2k_p,i·Δt)^0.5 for the current iteration step according to the oxidation rate coefficient; obtain the oxide film thickness δ_x,i(n) = δ_x,i(n-1) + Δδ_x,i(n) for the current iteration step according to the oxide film thickness δ_x,i(n-1) of the previous iteration step and the oxide film thickness increment of the current iteration step; determine whether |δ_x,i(n) - δ_x,i(n-1)| < ε (preset convergence threshold, such as 0.1μm) is true; if yes, stop the iteration; if no, update the basic wall temperature distribution based on the current oxide film thickness (considering the increase in wall temperature caused by the thermal resistance of the oxide film), and return to recalculate."

[0032] Step S40: Correct the basic wall temperature distribution using the oxide film thickness distribution to obtain the corrected metal wall temperature distribution.

[0033] In a specific implementation, after obtaining the above oxide film thickness distribution, the basic wall temperature distribution can be corrected based on the oxide film thickness distribution in this embodiment. The specific correction process is as follows: obtain the working fluid temperature, the inner-outer diameter ratio of the heated surface, and the heat load limit; determine the correction temperature by combining the working fluid temperature, the inner-outer diameter ratio of the heated surface, the heat load limit, the oxide film thickness distribution, and a preset coefficient; determine the outer wall temperature according to the correction temperature and the working fluid temperature, and correct the basic wall temperature distribution based on the outer wall temperature.

[0034] It should be noted that the corrected formula for calculating the outer wall temperature of the metal is t_wb = t_g + (q_max / α2)·[1 +(δ_m / λ_m + δ_ox / λ_ox)·β² / (β²-1)], where t_wb is the outer wall temperature (°C), t_g is the working fluid temperature (°C), q_max is the heat load limit (kW / m²), α2 is the working fluid side heat transfer coefficient (kW / (m²·°C)), δ_m is the pipe wall metal thickness (mm), λ_m is the metal thermal conductivity (W / (m·°C)), δ_ox is the oxide film thickness (mm), λ_ox is the oxide film thermal conductivity (W / (m·°C)), and β is the ratio of the inner to outer diameter of the heated surface. The preset coefficients include both the working fluid side heat transfer coefficient and the metal thermal conductivity.

[0035] Step S50: Based on the modified metal wall temperature distribution combined with the high-temperature creep fracture life model, evaluate the remaining life of the boiler heating surface.

[0036] It should be noted that the high-temperature creep fracture life model adopts the creep fracture life formula for T91 alloy proposed by ECCC: log(t ) = 15.2 - 13320 / (T+273) - 1.2·log(σ) The applicable conditions for this formula are: the material is T91 / P91 martensitic heat-resistant steel, the outer wall temperature T ranges from 550℃ to 650℃, the thermal stress σ ranges from 30MPa to 180MPa, and the fracture time t... The prediction range is 10³h~10 5 h.

[0037] Among them, t Where σ is the fracture time (h), T is the outer wall temperature (°C), and σ is the thermal stress of the heated surface (MPa). For heated surfaces made of other materials (such as 12Cr1MoV, TP347H, etc.), the ECCC creep rupture life formula for the corresponding material or the Larson-Miller parametric equation in the ASME standard are used for replacement calculation.

[0038] After completing the above calculations, calculate the ratio of the running time (t_used) to the fracture time (t_r): Di = t_used / t_r. If Di = 1, it is determined that the heated surface has reached the fracture life and needs to be replaced. If Di < 1, the remaining life is t_r - t_used.

[0039] Step S60: Perform explosion-proof control on the boiler heating surface based on the remaining lifespan of the boiler heating surface.

[0040] In this implementation, after obtaining the remaining lifespan of the boiler's heating surfaces, the risk level can be determined based on this remaining lifespan, thereby executing the corresponding explosion-proof control strategy. A high-risk level, for example, Di ≥ 0.8, meaning a remaining lifespan of less than or equal to 10,000 hours, indicates that the damage to the heating surfaces is approaching a critical value, and tube rupture may occur at any time due to overheating or stress concentration. A medium-risk level, for example, 0.5 ≤ Di < 0.8, meaning a remaining lifespan of less than or equal to 30,000 hours, indicates significant damage accumulation, requiring enhanced monitoring and gradual operational adjustments. A low-risk level, for example, Di < 0.5, meaning a remaining lifespan greater than 30,000 hours. Explosion-proof control strategies include at least one of the following: reducing burner sway angle, adjusting secondary air distribution, adjusting throttling coils, reducing superheater outlet temperature, and increasing steam flow to the tube panels. Furthermore, early warning prompts can include yellow and red warnings, where a yellow warning includes, for example, reducing the heat load, and a red warning includes, for example, shutting down the boiler for inspection.

[0041] This embodiment determines the basic wall temperature distribution by utilizing a preset metal wall temperature calculation model based on the flue gas side heat absorption deviation, steam side flow deviation, and thermal deviation coefficient calculated from the boiler's high-temperature heating surface structural parameters and operating conditions. Based on the basic wall temperature distribution, an oxide film growth prediction model iteratively calculates the oxide film thickness distribution. The basic wall temperature distribution is then corrected using the oxide film thickness distribution. Based on the corrected metal wall temperature distribution and a high-temperature creep fracture life model, the remaining lifespan of the boiler heating surface is assessed. Finally, explosion-proof control of the boiler heating surface is implemented based on its remaining lifespan. This method considers the dynamic influence of actual operating factors such as oxide film thermal resistance and thermal deviation on the wall temperature, improving the accuracy of remaining lifespan assessment and effectively enabling explosion-proof control of the heating surface.

[0042] Furthermore, this embodiment of the invention also proposes a storage medium storing an explosion-proof control program for the heating surface of a thermal power plant boiler. When the explosion-proof control program for the heating surface of a thermal power plant boiler is executed by a processor, it implements the steps of the explosion-proof control method for the heating surface of a thermal power plant boiler as described above.

[0043] Reference Figure 2 , Figure 2 This is a structural block diagram of the first embodiment of the explosion-proof control device for the heating surface of a thermal power plant boiler according to the present invention.

[0044] like Figure 2 As shown in the figure, the explosion-proof control device for the heating surface of a thermal power plant boiler proposed in this embodiment of the invention includes: Processing module 10 is used to calculate the flue gas side heat absorption deviation, steam side flow deviation, and thermal deviation coefficient based on the structural parameters of the boiler's high-temperature heating surface and operating conditions. The processing module 10 is used to determine the basic wall temperature distribution based on the flue gas side heat absorption deviation, the steam side flow deviation and the heat deviation coefficient using a preset metal wall temperature calculation model. The processing module 10 is used to iteratively calculate the oxide film thickness distribution based on the basic wall temperature distribution using an oxide film growth prediction model. The processing module 10 is used to correct the basic wall temperature distribution using the oxide film thickness distribution to obtain the corrected metal wall temperature distribution. The processing module 10 is used to evaluate the remaining life of the boiler heating surface based on the corrected metal wall temperature distribution combined with the high-temperature creep fracture life model. The control module 20 is used to perform explosion-proof control on the boiler heating surface based on the remaining lifespan of the boiler heating surface.

[0045] This embodiment determines the basic wall temperature distribution by utilizing a preset metal wall temperature calculation model based on the flue gas side heat absorption deviation, steam side flow deviation, and thermal deviation coefficient calculated from the boiler's high-temperature heating surface structural parameters and operating conditions. Based on the basic wall temperature distribution, an oxide film growth prediction model iteratively calculates the oxide film thickness distribution. The basic wall temperature distribution is then corrected using the oxide film thickness distribution. Based on the corrected metal wall temperature distribution and a high-temperature creep fracture life model, the remaining lifespan of the boiler heating surface is assessed. Finally, explosion-proof control of the boiler heating surface is implemented based on its remaining lifespan. This method considers the dynamic influence of actual operating factors such as oxide film thermal resistance and thermal deviation on the wall temperature, improving the accuracy of remaining lifespan assessment and effectively enabling explosion-proof control of the heating surface.

[0046] In some embodiments, the processing module 10 is used to construct a thermal deviation calculation model based on the structural parameters of the boiler's high-temperature heating surface and operating conditions. The thermal deviation calculation model includes a flue gas side heat absorption deviation calculation model, a steam side flow rate deviation calculation model, and a thermal deviation coefficient calculation model. The flue gas side heat absorption deviation calculation model is used to calculate the heat load distribution along the width and height of the flue through a heat load unevenness coefficient model. The steam side flow rate deviation calculation model is used to calculate the flow rate distribution between panels and among the pipes in the same panel based on the header connection form, pipe group resistance coefficient, and header static pressure distribution model. The thermal deviation coefficient calculation model is used to combine the heat load unevenness coefficient and the flow rate unevenness coefficient to obtain the thermal deviation coefficient of each pipe panel and each pipe in the same panel. The heat absorption deviation on the flue gas side, the flow rate deviation on the steam side, and the heat deviation coefficient are calculated using the aforementioned thermal deviation calculation model.

[0047] In some embodiments, the processing module 10 is configured to determine the oxidation rate coefficient based on the basic wall temperature distribution; The oxide film thickness increment is determined based on the oxidation rate coefficient. The oxide film thickness distribution is obtained based on the initial oxide film thickness and the oxide film thickness increment.

[0048] In some embodiments, the processing module 10 is used to obtain the working fluid temperature, the ratio of the inner and outer diameters of the heated surface, and the heat load limit. The correction temperature is determined by combining the working fluid temperature, the ratio of the inner and outer diameters of the heated surface, the heat load limit, the oxide film thickness distribution, and a preset coefficient, wherein the preset coefficient includes the working fluid heat transfer coefficient and the metal thermal conductivity. The outer wall temperature is determined based on the corrected temperature and the working fluid temperature, and the basic wall temperature distribution is corrected based on the outer wall temperature.

[0049] In some embodiments, the processing module 10 is used to determine the outer wall temperature based on the corrected metal wall temperature distribution; Determine the thermal stress on the heated surface; The fracture time is determined based on the thermal stress and the outer wall temperature. The remaining life of the boiler's heating surfaces is assessed based on the boiler's operating time and the fracture time.

[0050] In some embodiments, the control module 20 is configured to determine a risk level based on the remaining lifespan of the boiler heating surface; Based on the risk level, a corresponding explosion-proof control strategy is implemented. The explosion-proof control strategy includes at least one of the following: reducing the burner swing angle, adjusting the secondary air distribution, adjusting the throttling ring, reducing the superheater outlet temperature, and increasing the steam flow rate of the tube panel. Based on the risk level, a corresponding early warning is triggered, which is used to remind the user to reduce the heat load or perform emergency maintenance.

[0051] This application embodiment also provides an explosion-proof control device for the heating surface of a thermal power plant boiler, including a processor, a communication interface, a memory, and a communication bus. The processor, communication interface, and memory communicate with each other through the communication bus. The memory is used to store the explosion-proof control program for the heating surface of the thermal power plant boiler. When the processor executes the program stored in the memory, it implements the above-mentioned explosion-proof control method for the heating surface of the thermal power plant boiler.

[0052] The communication bus mentioned in the explosion-proof control equipment for the heating surface of the boiler in the aforementioned thermal power plant can be a Peripheral Component Interconnect (PCI) bus or an Extended Industry Standard Architecture (EISA) bus, etc. This communication bus can be divided into address bus, data bus, control bus, etc.

[0053] The communication interface is used for communication between the aforementioned explosion-proof control equipment for the heating surface of the boiler in the thermal power plant and other equipment.

[0054] The memory may include random access memory (RAM) or non-volatile memory (NVM), such as at least one disk storage device. Optionally, the memory may also be at least one storage device located remotely from the aforementioned processor.

[0055] The processors mentioned above can be general-purpose processors, including central processing units (CPUs), network processors (NPs), etc.; they can also be digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components.

[0056] In the above embodiments, implementation can be achieved entirely or partially through software, hardware, firmware, or any combination thereof. When implemented using software, it can be implemented entirely or partially as a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, all or part of the processes or functions described in the embodiments of this application are generated. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions can be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another. For example, the computer instructions can be transmitted from one website, computer, server, or data center to another website, computer, server, or data center via wired (e.g., coaxial cable, fiber optic, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) means. The computer-readable storage medium can be any available medium that a computer can access or a data storage device such as a server or data center that integrates one or more available media. The available medium can be a magnetic medium (e.g., floppy disk, hard disk, magnetic tape), an optical medium (e.g., DVD), or a semiconductor medium (e.g., solid state disk (SSD)).

[0057] 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 a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0058] The various embodiments in this specification are described in a related manner. Similar or identical parts between embodiments can be referred to mutually. Each embodiment focuses on describing the differences from other embodiments. In particular, the system embodiments are basically similar to the method embodiments, so the description is relatively simple; relevant parts can be referred to the descriptions of the method embodiments.

[0059] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

[0060] It should be understood that the above are merely illustrative examples and do not constitute any limitation on the technical solution of the present invention. In specific applications, those skilled in the art can make settings as needed, and the present invention does not impose any restrictions on this.

[0061] It should be noted that the workflow described above is merely illustrative and does not limit the scope of protection of this invention. In practical applications, those skilled in the art can select some or all of the workflow to achieve the purpose of this embodiment according to actual needs, and no restrictions are imposed here.

[0062] In addition, for technical details not described in detail in this embodiment, please refer to the explosion-proof control method for the heating surface of a thermal power plant boiler provided in any embodiment of the present invention, which will not be repeated here.

[0063] Furthermore, it should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or system that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or system. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or system that includes that element.

[0064] The sequence numbers of the above embodiments of the present invention are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments.

[0065] Through the above description of the embodiments, those skilled in the art can clearly understand that the methods of the above embodiments can be implemented by means of software plus necessary general-purpose hardware platforms. Of course, they can also be implemented by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product is stored in a storage medium (such as read-only memory (ROM) / RAM, magnetic disk, optical disk) and includes several instructions to cause a terminal device (which may be a mobile phone, computer, server, or network device, etc.) to execute the methods described in the various embodiments of the present invention.

[0066] The above are merely preferred embodiments of the present invention and do not limit the scope of the patent. Any equivalent structural or procedural transformations made based on the description and drawings of the present invention, or direct or indirect applications in other related technical fields, are similarly included within the scope of patent protection of the present invention.

[0067] It is understood that the system provided in the embodiments of the present invention corresponds to the method provided in the embodiments of the present invention, and the explanation, examples and beneficial effects of the relevant content can be referred to the corresponding parts of the above methods.

Claims

1. A method for explosion-proof control of the heating surface of a thermal power plant boiler, characterized in that, The explosion-proof control method for the heating surface of a thermal power plant boiler includes: Calculate the flue gas side heat absorption deviation, steam side flow deviation, and thermal deviation coefficient based on the boiler high-temperature heating surface structural parameters and operating conditions. The basic wall temperature distribution is determined using a preset metal wall temperature calculation model based on the heat absorption deviation on the flue gas side, the flow deviation on the steam side, and the thermal deviation coefficient. Based on the aforementioned basic wall temperature distribution, the oxide film thickness distribution is iteratively calculated using an oxide film growth prediction model. The basic wall temperature distribution is corrected using the oxide film thickness distribution to obtain the corrected metal wall temperature distribution; Based on the modified metal wall temperature distribution combined with the high-temperature creep fracture life model, the remaining life of the boiler heating surface is evaluated. Explosion-proof control of the boiler heating surface is implemented based on the remaining lifespan of the boiler heating surface.

2. The explosion-proof control method for the heating surface of a thermal power plant boiler as described in claim 1, characterized in that, The calculation of flue gas side heat absorption deviation, steam side flow deviation, and heat deviation coefficient based on boiler high-temperature heating surface structural parameters and operating conditions includes: A thermal deviation calculation model is constructed based on the structural parameters of the boiler's high-temperature heating surface and operating conditions. The thermal deviation calculation model includes a flue gas side heat absorption deviation calculation model, a steam side flow rate deviation calculation model, and a thermal deviation coefficient calculation model. The flue gas side heat absorption deviation calculation model is used to calculate the heat load distribution along the width and height of the flue using a heat load unevenness coefficient model. The steam side flow rate deviation calculation model is used to calculate the flow rate distribution between panels and among the pipes in the same panel based on the header connection form, pipe group resistance coefficient, and header static pressure distribution model. The thermal deviation coefficient calculation model is used to combine the heat load unevenness coefficient and the flow rate unevenness coefficient to obtain the thermal deviation coefficient of each pipe panel and among the pipes in the same panel. The heat absorption deviation on the flue gas side, the flow rate deviation on the steam side, and the heat deviation coefficient are calculated using the aforementioned thermal deviation calculation model.

3. The explosion-proof control method for the heating surface of a thermal power plant boiler as described in claim 1, characterized in that, The step of iteratively calculating the oxide film thickness distribution using an oxide film growth prediction model based on the basic wall temperature distribution includes: The oxidation rate coefficient for the current iteration step is determined based on the aforementioned basic wall temperature distribution; The oxide film thickness increment for the current iteration step is determined based on the oxidation rate coefficient. The oxide film thickness of the current iteration step is obtained based on the oxide film thickness of the previous iteration step and the oxide film thickness increment of the current iteration step. Determine whether the difference between the oxide film thickness of the current iteration step and the oxide film thickness of the previous iteration step is less than a preset convergence threshold; If so, stop the iteration and use the oxide film thickness of the current iteration step as the oxide film thickness distribution; If not, update the base wall temperature distribution based on the oxide film thickness of the current iteration step, and return to the step of determining the oxidation rate coefficient based on the updated base wall temperature distribution.

4. The explosion-proof control method for the heating surface of a thermal power plant boiler as described in claim 1, characterized in that, The method of correcting the basic wall temperature distribution using the oxide film thickness distribution includes: Obtain the working fluid temperature t_g, the ratio of the inner and outer diameters of the heated surface β, and the heat load limit q_max; The correction temperature Δt_corr is determined by combining the working fluid temperature t_g, the inner-outer diameter ratio β of the heated surface, the heat load limit q_max, the oxide film thickness distribution δ_ox, and a preset coefficient. The correction temperature Δt_corr = q_max·δ_ox / λ_ox, where λ_ox is the thermal conductivity of the oxide film. The outer wall temperature t_wb is determined based on the corrected temperature Δt_corr and the working fluid temperature t_g: t_wb = t_g + (q_max / α2)·(1 + (δ_m / λ_m)·β² / (β²-1)) + Δt_corr, where δ_m is the thickness of the pipe wall metal, λ_m is the thermal conductivity of the metal, and α2 is the heat transfer coefficient on the working fluid side. The basic wall temperature distribution is corrected based on the outer wall temperature t_wb.

5. The method of claim 4, wherein the method comprises: The assessment of the remaining life of the boiler heating surface based on the modified metal wall temperature distribution combined with the high-temperature creep fracture life model includes: The outer wall temperature is determined based on the corrected metal wall temperature distribution. Determine the thermal stress on the heated surface; The fracture time is determined based on the thermal stress and the outer wall temperature. The remaining life of the boiler's heating surfaces is assessed based on the boiler's operating time and the fracture time.

6. The method of claim 1, wherein the method is a method of explosion prevention control of a boiler heating surface of a thermal power plant. The method of controlling the explosion-proof performance of the boiler heating surface based on its remaining lifespan includes: The risk level is determined based on the ratio D_i of the remaining lifespan of the boiler's heating surface to the operating time. If D_i ≥ 0.8, it is determined to be a high-risk level; if 0.5 ≤ D_i < 0.8, it is determined to be a medium-risk level; and if D_i < 0.5, it is determined to be a low-risk level. Based on the risk level, a corresponding explosion-proof control strategy is implemented. The explosion-proof control strategy includes at least one of the following: reducing the burner swing angle, adjusting the secondary air distribution, adjusting the throttling ring, reducing the superheater outlet temperature, and increasing the steam flow rate of the tube panel. Based on the risk level, a corresponding early warning is triggered. The high-risk level corresponds to a red warning, and the medium-risk level corresponds to a yellow warning. The early warning is used to remind the user to reduce the heat load or perform emergency maintenance.

7. An explosion-proof control device for the heating surface of a thermal power plant boiler, characterized in that, The explosion-proof control device for the heating surface of the thermal power plant boiler includes: The thermal deviation calculation module is used to calculate the heat absorption deviation on the flue gas side, the flow deviation on the steam side, and the thermal deviation coefficient based on the structural parameters of the boiler's high-temperature heating surface and operating conditions, and outputs the thermal deviation coefficient to the wall temperature calculation module. The wall temperature calculation module is used to receive the thermal deviation coefficient, determine the basic wall temperature distribution using a preset metal wall temperature calculation model, and output the basic wall temperature distribution to the oxide film calculation module. The oxide film calculation module is used to receive the basic wall temperature distribution, iteratively calculate the oxide film thickness distribution using the oxide film growth prediction model, correct the basic wall temperature distribution using the oxide film thickness distribution to obtain the corrected metal wall temperature distribution, and output the corrected metal wall temperature distribution to the lifetime assessment module. The life assessment module is used to receive the corrected metal wall temperature distribution, assess the remaining life of the boiler heating surface in combination with the high temperature creep fracture life model, and output the remaining life to the control module. The control module is used to receive the remaining lifespan and perform explosion-proof control on the boiler heating surface based on the remaining lifespan of the boiler heating surface.

8. The explosion-proof control device for the heating surface of a thermal power plant boiler as described in claim 7. Its characteristic is that, The thermal deviation calculation module is used to construct a thermal deviation calculation model based on the structural parameters of the boiler's high-temperature heating surface and operating conditions. The thermal deviation calculation model includes a flue gas side heat absorption deviation calculation model, a steam side flow rate deviation calculation model, and a thermal deviation coefficient calculation model. in, The flue gas side heat absorption deviation calculation model is used to calculate the heat load distribution along the width and height of the flue through the heat load unevenness coefficient model. The steam side flow deviation calculation model is used to calculate the flow distribution between screens and among the pipes in the same screen based on the header connection form, pipe group resistance coefficient and header static pressure distribution model. The heat deviation coefficient calculation model is used to combine the heat load unevenness coefficient and the flow unevenness coefficient to obtain the heat deviation coefficient of each pipe screen and each pipe in the same screen. The heat absorption deviation on the flue gas side, the flow rate deviation on the steam side, and the heat deviation coefficient are calculated using the aforementioned thermal deviation calculation model.

9. An explosion-proof control device for the heating surface of a thermal power plant boiler, characterized in that, The explosion-proof control device for the heating surface of a thermal power plant boiler includes: a memory, a processor, and an explosion-proof control program for the heating surface of a thermal power plant boiler stored in the memory and executable on the processor. The explosion-proof control program for the heating surface of a thermal power plant boiler is configured to implement the steps of the explosion-proof control method for the heating surface of a thermal power plant boiler as described in any one of claims 1 to 6.

10. A storage medium, characterized in that, The storage medium stores an explosion-proof control program for the heating surface of a thermal power plant boiler. When the processor executes the explosion-proof control program for the heating surface of a thermal power plant boiler, it implements the steps of the explosion-proof control method for the heating surface of a thermal power plant boiler as described in any one of claims 1 to 6.

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