Boiler heating surface soot blowing control method

Abstract

The invention provides a soot blowing control method for a boiler heating surface, and belongs to the technical field of boilers. The method comprises the following steps: inputting operating parameters required by coal quality low-grade heating value and pollution rate identification of a boiler under the current working condition into a pre-constructed exhaust gas temperature prediction model to obtain boiler exhaust gas temperature of each heating surface under the current working condition; calculating required operation parameters based on the coal quality lower heating value and heating surface heat absorption of the boiler under the current working condition to obtain a heat exchange coefficient factor of each heating surface under the current working condition; the heating surfaces with the boiler smoke exhaust temperature larger than a preset temperature threshold value are determined as heating surfaces to be subjected to soot blowing, the heating surfaces to be subjected to soot blowing are sequenced on the basis of heat exchange coefficient factors of the heating surfaces to be subjected to soot blowing, and the soot blowing sequence of the heating surfaces to be subjected to soot blowing is determined; and according to the soot blowing sequence of the heating surface to be subjected to soot blowing, soot blowers corresponding to the heating surface to be subjected to soot blowing are controlled to blow soot. According to the invention, soot blowing can be carried out on the heating surface of the boiler as required, and the safety and economical efficiency of unit operation are improved.

Description

Technical Field

[0001] The invention relates to the technical field of boilers, and in particular to a soot blowing control method for a boiler heating surface. Background Art

[0002] The ash in coal will cause ash accumulation and slagging problems in coal-fired power plant boilers, which will reduce the heat exchange efficiency and cause the boiler efficiency to drop and the exhaust gas temperature to rise. Therefore, in order to ensure the normal operation of the boiler, it is necessary to regularly blow and remove the ash from the heating surface.

[0003] In order to achieve the goals of carbon peak and carbon neutrality, the installed capacity of new energy power generation needs to be increased. However, due to the unstable characteristics of wind and solar energy, coal-fired power plants need to improve their operational flexibility to maintain stable operation of the power grid.

[0004] However, when the coal-fired power plant is in flexible operation mode, the ash accumulation and slagging characteristics of the boiler are significantly different from those in base load operation, which makes the traditional timed and quantitative sootblowing strategy mismatch with the actual sootblowing needs of the heating surface, resulting in "underblowing" or "overblowing" of the heating surface locally or even globally. "Underblowing" will cause the exhaust gas temperature to rise and reduce the boiler efficiency. In severe cases, it may cause increased flue resistance and serious slagging and falling in the furnace; "overblowing" not only wastes sootblowing steam, but also causes the heating surface tube wall to become thinner due to blowing damage, increasing the risk of tube burst.

[0005] In short, in the flexible operation mode of coal-fired power plants, the traditional timed and quantitative soot blowing strategy cannot achieve soot blowing on demand, thereby reducing the safety and economy of unit operation. Summary of the invention

[0006] The purpose of the embodiment of the present invention is to provide a boiler heating surface sootblowing control method to solve the problem of reduced safety and economy of unit operation.

[0007] In order to achieve the above object, an embodiment of the present invention provides a boiler heating surface sootblowing control method, comprising: Obtain the operating parameters required for the identification of the low calorific value of coal quality and pollution rate and the calculation of the heat absorption of the heating surface under the current working conditions of the boiler; The operating parameters required for identifying the low calorific value of coal and the pollution rate are input into the pre-built exhaust gas temperature prediction model to obtain the boiler exhaust gas temperature of each heating surface under the current working conditions; Based on the low calorific value of coal and the heat absorption of the heating surface, the required operating parameters are calculated to obtain the heat transfer coefficient factors of each heating surface under the current working conditions; The heating surfaces whose boiler exhaust gas temperature is greater than a preset temperature threshold are determined as the heating surfaces to be sootblown, and the heating surfaces to be sootblown are sorted based on the heat transfer coefficient factors of the heating surfaces to be sootblown to determine the sootblowing order of the heating surfaces to be sootblown; According to the sootblowing sequence of the heating surface to be sootblown, the sootblowers corresponding to the heating surface to be sootblown are controlled to perform sootblowing.

[0008] Optionally, the calculation rule for the low calorific value of coal quality is: ;in, Indicates the low calorific value of coal; represents the coefficient related to efficiency; Indicates the total heat of the boiler; Indicates the amount of coal entering the furnace.

[0009] Optionally, the calculation rule for the total heat of the boiler is: ;in, Indicates the total heat of the boiler; Indicates the effective heat absorption of the boiler; Indicates the total heat of exhaust gas; It indicates the percentage of effective heat absorption of boiler to the total heat of boiler; Indicates exhaust heat loss.

[0010] Optionally, the calculation rule for the total heat of the boiler is: ;in, Indicates the total heat of the boiler; Indicates the effective heat absorption of the boiler; Indicates the total heat of exhaust gas; Indicates heat loss due to incomplete combustion of combustible gas; Indicates heat loss due to incomplete combustion of solids; Indicates heat dissipation loss; Represents the physical heat loss of ash.

[0011] Optionally, the calculation rule of the effective heat absorption of the boiler is: ;in, Indicates the effective heat absorption of the boiler; Indicates the main steam flow rate; represents the main steam enthalpy; Indicates water supply flow rate; represents the feed water enthalpy; Indicates the cooling water flow rate; represents the reheat steam enthalpy; represents the desuperheating water enthalpy; Indicates the reheat steam flow rate; It represents the exhaust enthalpy of high pressure cylinder;

[0012] The calculation rule for the total heat of exhaust gas is: ;in, Indicates the total heat of exhaust gas; Indicates exhaust gas temperature; Indicates the reference temperature; Indicates the total air volume.

[0013] Optionally, the calculation rule for the heat loss of incomplete combustion of solids is: ;in, Indicates heat loss due to incomplete combustion of solids; Indicates the received ash content of the fuel; It indicates the mass percentage of slag in the total ash of coal; Indicates the mass percentage of carbon in the slag; It indicates the percentage of fly ash content in the total ash content of coal; Indicates the mass percentage of carbon in fly ash; It expresses the boiler heat input per kg of fuel;

[0014] The calculation rule for heat dissipation loss is: ;in, Indicates heat dissipation loss; Indicates the design value of heat dissipation loss under 100% load; Indicates the amount of boiler fuel;

[0015] The calculation rule of ash physical heat loss is: ;in, Indicates the physical heat loss of ash; Indicates ash content; Indicates the calorific value of the fuel; Indicates the slag content; Indicates the slag temperature; Indicates the supply air temperature; It indicates the specific heat capacity of slag; Indicates the carbon content of slag; Indicates fly ash content; Indicates exhaust gas temperature; represents the specific heat capacity of fly ash; Indicates fly ash content; Indicates the content of settled ash; Indicates the temperature of settled ash; It represents the specific heat capacity of the settled ash; Indicates the carbon content of settled ash.

[0016] Optionally, the operating parameters required for pollution rate identification include: boiler status, sootblowing operation parameters and particulate matter emission monitoring data; The operating parameters required for the calculation of heat absorption of the heating surface include: flue gas volume, flue gas enthalpy difference between the inlet and outlet of each heating surface, and the ideal heat transfer capacity of the heating surface.

[0017] Optionally, the pre-built exhaust temperature prediction model is trained by: Obtain the low calorific value of coal quality under different working conditions, the operating parameters required for pollution rate identification, and the actual boiler exhaust temperature of each heating surface of the boiler; Taking the operating parameters required for identifying the low calorific value and pollution rate of coal under different operating conditions as input, the pre-constructed deep learning algorithm model outputs the predicted boiler exhaust temperature of each heating surface of the boiler under different operating conditions, and adjusts the model parameters of the deep learning algorithm model according to the difference between the predicted boiler exhaust temperature of each heating surface of the boiler under different operating conditions and the actual boiler exhaust temperature of each heating surface of the boiler, until the difference between the predicted boiler exhaust temperature of each heating surface of the boiler under different operating conditions output by the deep learning algorithm model and the actual boiler exhaust temperature of each heating surface of the boiler is lower than the preset threshold, so as to obtain the exhaust temperature prediction model.

[0018] Optionally, the calculation rule of the heat transfer coefficient factor of each heating surface is: ;in, Indicates the heat transfer coefficient factor of each heating surface; Indicates the amount of smoke; Indicates the flue gas enthalpy value at the inlet of each heating surface; Indicates the flue gas enthalpy value at the outlet of each heating surface; Represents the ideal heat transfer capacity of each heating surface.

[0019] Optionally, the calculation rule of the flue gas volume is: ;in, Indicates the amount of smoke; Indicates the low calorific value of coal; Indicates the CO2 content of flue gas; The calculation rules are: ; Indicates the amount of dry air required for coal combustion; The calculation rules are: ;

[0020] The calculation rule for the flue gas enthalpy at the inlet of each heating surface is: ; represents the flue gas enthalpy at the inlet of each heating surface; where, , , , , , Indicates the dry air coefficient at the inlet and outlet of the heating surface; represents the flue gas temperature at the inlet of the i-th heating surface; , , , , Indicates the water vapor coefficient at the inlet and outlet of the heating surface; , , , , Indicates the carbon dioxide coefficient at the inlet and outlet of the heating surface;

[0021] The calculation rule for the flue gas enthalpy at the outlet of each heating surface is: ;in, Indicates the flue gas enthalpy value at the outlet of each heating surface; The flue gas temperature at the outlet of the i+1th heating surface.

[0022] The present invention has the following beneficial effects: (1) Compared with traditional mechanism modeling, the intelligent sootblowing system based on data analysis and modeling has strong applicability and high accuracy. It can be extended to different systems of different types of coal-fired power plants, and can effectively guide the operation of operators or directly control them, so that the unit monitoring personnel can clearly understand the sootblowing goals, which is of great significance to the energy saving and consumption reduction of the unit and the improvement of economic benefits. (2) Compared with the optimization and transformation of boiler equipment, the boiler heating surface sootblowing control method provided by the present invention is low-cost, safe and reliable, and can be integrated into the intelligent power generation operation control system to improve the unit operation efficiency under various working conditions.

[0023] Other features and advantages of the embodiments of the present invention will be described in detail in the subsequent detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The accompanying drawings are used to provide a further understanding of the embodiments of the present invention and constitute a part of the specification. Together with the following specific implementations, they are used to explain the embodiments of the present invention, but do not constitute a limitation on the embodiments of the present invention. In the accompanying drawings: Figure 1 It is a schematic flow chart of a boiler heating surface sootblowing control method provided by an embodiment of the present invention; Figure 2 is a schematic diagram of the composition of the heating surface provided by an embodiment of the present invention; Figure 3 is a schematic diagram of an application interface of an intelligent sootblowing system provided by an embodiment of the present invention; Figure 4 is a schematic diagram of a sootblowing statistics interface of an intelligent sootblowing system provided by an embodiment of the present invention; Figure 5 It is a structural schematic diagram of a boiler heating surface sootblowing control system provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0025] The specific implementation of the embodiment of the present invention is described in detail below in conjunction with the accompanying drawings. It should be understood that the specific implementation described here is only used to illustrate and explain the embodiment of the present invention, and is not used to limit the embodiment of the present invention.

[0026] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by technicians in the technical field to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit this application.

[0027] In the description of the embodiments of the present application, the technical terms "first", "second", etc. are only used to distinguish different objects, and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features. In the description of the embodiments of the present application, the meaning of "multiple" is more than two, unless otherwise clearly and specifically defined.

[0028] Embodiment 1 Please refer to Figure 1 , Figure 1 : is a flow chart of a boiler heating surface sootblowing control method provided by an embodiment of the present invention, the method comprising: S100, obtaining the low calorific value of coal quality and the operating parameters required for pollution rate identification and the operating parameters required for heat absorption calculation of the heating surface of the boiler under the current operating conditions; It should be noted that, due to the complexity and variability of coal quality and types, with the changes in the coal blending mode and operation combination mode of the unit, the coal quality entering the boiler often fluctuates. In order to effectively overcome the impact of coal quality fluctuations on the operation and control of the boiler, the classic BUT correction method is often used to correct the fuel. However, since the traditional BTU correction adopts a slow integral correction model, the coal quality correction is not timely and the control quality of the unit deteriorates. Therefore, the present invention proposes a coal quality online identification method based on real-time soft measurement of low calorific value of coal quality, which is mainly based on the energy balance relationship of the boiler steam-water system, constructs a soft measurement model of low calorific value of coal quality, and realizes real-time calculation and monitoring of the coal quality entering the furnace.

[0029] The main principle is as follows: On the basis of the known values ​​of the steam-water process such as the coal feed rate, steam pressure, and temperature, the effective heat absorbed by the working fluid in the boiler can be expressed as the sum of the heat absorbed by the main steam and the reheated steam, minus the heat consumed by heating the feed water and the heat consumed by the superheater and reheater cooling water. The enthalpy of the working fluid involved can be calculated using the temperature and pressure values ​​of the working fluid at that moment, and combined with the total heat consumed by the exhaust gas, the total heat released inside the boiler can be obtained. The heat released by the unit amount of fuel during this period of time can be expressed as the low calorific value of the coal.

[0030] Specifically, the calculation rules for the low calorific value of coal quality are: ;in, Indicates the low calorific value of coal, MJ / kg; Represents the efficiency-related coefficient, in this case k=1; Indicates the total heat of the boiler, MW; Indicates the amount of coal fed into the furnace, kg / s.

[0031] Among them, the calculation rules of the total heat of the boiler have the following two implementation methods: (1) ;in, Indicates the total heat of the boiler, MW; Indicates the effective heat absorption of the boiler, MW; Indicates the total heat of exhaust gas, MW; It indicates the percentage of effective heat absorption of boiler to the total heat of boiler, %; Represents exhaust heat loss, %.

[0032] (2) ;in, Indicates the total heat of the boiler, MW; Indicates the effective heat absorption of the boiler, MW; Indicates the total heat of exhaust gas, MW; Indicates the heat loss of incomplete combustion of combustible gas, %; Indicates heat loss due to incomplete combustion of solids, %; Represents heat dissipation loss, %; Represents the physical heat loss of ash, %.

[0033] Among them, the calculation rule of the effective heat absorption of the boiler is: ;in, Indicates the effective heat absorption of the boiler, MW; Indicates the main steam flow rate, kg / s; represents the main steam enthalpy, MJ / kg; Indicates water flow rate, kg / s; represents the feed water enthalpy, MJ / kg; Indicates the cooling water flow rate, kg / s; represents the reheat steam enthalpy, MJ / kg; represents the desuperheating water enthalpy, MJ / kg; Indicates the reheat steam flow rate, kg / s; It represents the exhaust enthalpy of high pressure cylinder, MJ / kg;

[0034] The calculation rule for the total heat of exhaust gas is: ;in, Indicates the total heat of exhaust gas, MW; Indicates exhaust gas temperature, °C; Indicates the reference temperature, °C; Indicates total air volume, kg / s.

[0035] Among them, the calculation rule for heat loss of incomplete combustion of solids is: ;in, Indicates heat loss due to incomplete combustion of solids, %; Indicates the received ash content of the fuel, %; It indicates the mass percentage of slag in the total ash of coal, %; Indicates the mass percentage of carbon in the slag, %; It indicates the mass percentage of fly ash to the total ash of coal combustion, %; Indicates the mass percentage of carbon in fly ash, %; It indicates the boiler heat input per kilogram of fuel, MJ / kg;

[0036] The calculation rule for heat dissipation loss is: ;in, Represents heat dissipation loss, %; Indicates the design value of heat dissipation loss under 100% load, %; Indicates the amount of boiler fuel, kg;

[0037] The calculation rule of ash physical heat loss is: ;in, Represents the physical heat loss of ash, %; Indicates ash content, kg; Indicates the calorific value of the fuel, MJ / kg; Indicates the slag content, kg; Indicates slag temperature, °C; Indicates the supply air temperature, °C; It represents the specific heat capacity of slag, J / (kg·℃); Indicates the carbon content of slag, kg; Indicates fly ash content, kg; Indicates exhaust gas temperature, °C; represents the specific heat capacity of fly ash, J / (kg·℃); Indicates fly ash content, kg; Indicates the content of settled ash, kg; Indicates the temperature of the settled ash, °C; It represents the specific heat capacity of the settled ash, J / (kg·℃); Indicates the carbon content of settled ash, kg.

[0038] The operating parameters required for pollution rate identification include, but are not limited to: boiler status, sootblowing operating parameters and particulate matter emission monitoring data.

[0039] The operating parameters required for the heating surface to absorb heat include but are not limited to: flue gas volume, flue gas enthalpy difference between the inlet and outlet of each heating surface, and ideal heat exchange of the heating surface.

[0040] Since the operating parameters of coal-fired units are different under different operating conditions, and of course the operating parameters of the boiler heating surface are different under different operating conditions, it is necessary to divide the operating parameters required for identifying the low calorific value of coal quality and the pollution rate and the operating parameters required for calculating the heat absorption of the heating surface into the operating parameters required for identifying the low calorific value of coal quality and the pollution rate under different operating conditions and the operating parameters required for calculating the heat absorption of the heating surface. Only then can sootblowing guidance be carried out for the heating surface under different operating conditions.

[0041] In one embodiment, before dividing the operating parameters required for identifying the low calorific value of coal quality and the pollution rate and the operating parameters required for heat absorption by the heating surface, the data needs to be preprocessed: (1) Data quality analysis: refers to the detection of missing values ​​and outliers, and the relevant processing. Its purpose is to improve the quality of the data on the one hand, and to make the data better adaptable to specific mining techniques or tools on the other hand. Algorithms related to missing value processing: automatic deletion of related records, mean / median / mode interpolation, fixed value interpolation, nearest neighbor interpolation, regression method interpolation, interpolation method interpolation (Lagrange, Newton method, hermite interpolation, segmented interpolation, spline interpolation), no processing, etc. Algorithms related to outlier processing: outlier deletion, treating as missing values, mean value correction, no processing. Algorithms related to data noise processing: parameter smoothing related algorithms; (2) Data resampling: Data is resampled and the new sampling period is an integer multiple of the previous one. The purpose is to remove some noise, adapt to the requirements of the modeling algorithm, and reduce the amount of data to increase the speed of subsequent modeling.

[0042] S200, inputting the operating parameters required for identifying the low calorific value of coal quality and the pollution rate into a pre-built flue gas temperature prediction model to obtain the boiler flue gas temperature of each heating surface under the current working condition; Among them, the pre-built exhaust temperature prediction model is trained by the following method: S210, obtaining the low calorific value of coal quality under different working conditions, the operating parameters required for the pollution rate identification, and the actual boiler exhaust gas temperature of each heating surface of the boiler; S220, taking the operating parameters required for identifying the low calorific value and pollution rate of coal under different operating conditions as input, the pre-constructed deep learning algorithm model outputs the predicted boiler exhaust temperature of each heating surface of the boiler under different operating conditions, and adjusts the model parameters of the deep learning algorithm model according to the difference between the predicted boiler exhaust temperature of each heating surface of the boiler under different operating conditions and the actual boiler exhaust temperature of each heating surface of the boiler, until the difference between the predicted boiler exhaust temperature of each heating surface of the boiler under different operating conditions output by the deep learning algorithm model and the actual boiler exhaust temperature of each heating surface of the boiler is lower than the preset threshold, thereby obtaining the exhaust temperature prediction model.

[0043] It should be noted that the purpose of identifying the pollution rate of the heating surface is to find out the areas of each heating surface that are prone to dust accumulation or slagging and their corresponding sootblowers. If the dust accumulation and slagging in the corresponding area of ​​a sootblower are serious, the pollution factor will change greatly. If the slagging in a sootblower area is serious before sootblowing, since the heat transfer resistance of this area is large, the working fluid in the tube absorbs less heat, the temperature is low, and the corresponding boiler tube panel wall temperature is also low. Therefore, the present invention uses the prediction of the boiler exhaust temperature as the basis for judging the pollution rate of the boiler heating surface.

[0044] It can be seen that the input of the model training in this step is the boiler status, soot blowing operation parameters, particulate emission monitoring data, etc., and the output result is the boiler exhaust temperature.

[0045] Deep learning algorithm models include but are not limited to: mechanism models, linear regression models, and nonlinear model structures.

[0046] The mechanism model has a clear physical meaning and can reflect the main dynamic characteristics of the process. The model can be expressed in partial differential form, differential form or algebraic form according to its complexity. Generally speaking, the model with high accuracy will also have high complexity.

[0047] Linear regression models mainly include CARMA, CARIMA and other model structures. The parameter estimation algorithm usually uses the least squares method, has clear requirements for input signal excitation, has a well-developed theory, and is suitable for application scenarios with high linearity.

[0048] Nonlinear model structures, such as machine learning and neural network models, can describe and predict system behavior in general. Their internal parameters have no physical meaning. Their advantage is high nonlinear fitting accuracy, but their disadvantage is that the model has many weight parameters and the calculation takes a long time.

[0049] S300, based on the low calorific value of coal quality and the heat absorption of the heating surface, the required operating parameters are calculated to obtain the heat transfer coefficient factor of each heating surface under the current working condition; It should be noted that the conventional calculation method for heat absorption of the heating surface in the furnace usually only selects several dangerous sections of a single tube in the same screen for calculation. During the calculation process, a series of empirical coefficients such as the heating unevenness coefficient, structural inequality coefficient, hydraulic deviation coefficient, etc. at the section are selected according to experience to obtain the heat load at the section and the working fluid flow in the tube, so as to calculate the steam temperature, wall temperature and heat absorption changes at the section, but such calculation method has poor accuracy. Therefore, the present invention adopts the coal quality online identification model analysis data to calculate the heat release on the flue gas side.

[0050] It is understandable that due to the different series of coefficients of different heating surfaces, the flue gas specific enthalpy difference of each heating surface is obtained by subtracting the flue gas specific enthalpy at the inlet and outlet of each heating surface. After calculating the flue gas specific enthalpy of each heating surface, multiply it by the flue gas volume to obtain the heat absorption of the heating surface.

[0051] In one embodiment, referring to Figure 2 Along the flow direction of the flue gas, the heating surface may include the furnace heating surface, the platen superheater heating surface, the high-temperature superheater heating surface and the high-temperature reheater heating surface.

[0052] The specific calculation method is as follows: The calculation rule of the heat transfer coefficient factor of each heating surface is: ;in, Indicates the heat transfer coefficient factor of each heating surface; Indicates the amount of smoke; Indicates the flue gas enthalpy value at the inlet of each heating surface; Indicates the flue gas enthalpy value at the outlet of each heating surface; Represents the ideal heat transfer capacity of each heating surface.

[0053] The calculation rule of flue gas volume is: ;in, Indicates the amount of smoke; Indicates the low calorific value of coal; Indicates the CO2 content of flue gas; The calculation rules are: ; Indicates the amount of dry air required for coal combustion; The calculation rules are: ;

[0054] The calculation rule for the flue gas enthalpy at the inlet of each heating surface is: ;in, Indicates the flue gas enthalpy value at the inlet of each heating surface; , , , , , Indicates the dry air coefficient at the inlet and outlet of the heating surface; represents the flue gas temperature at the inlet of the i-th heating surface; , , , , Indicates the water vapor coefficient at the inlet and outlet of the heating surface; , , , , Indicates the carbon dioxide coefficient at the inlet and outlet of the heating surface;

[0055] The calculation rule for the flue gas enthalpy at the outlet of each heating surface is: ;in, Indicates the flue gas enthalpy value at the outlet of each heating surface; The flue gas temperature at the outlet of the i+1th heating surface.

[0056] S400, determining a heating surface whose boiler exhaust temperature is greater than a preset temperature threshold as a heating surface to be sootblown, and sorting the heating surfaces to be sootblown based on the heat transfer coefficient factors of the heating surfaces to be sootblown, and determining a sootblowing order for the heating surfaces to be sootblown; Specifically, when the value of the boiler exhaust gas temperature of the heating surface is low, it means that the heating surface is not polluted and soot blowing is not required. When the value of the heat transfer coefficient factor of each heating surface is larger, it means that the heating surface is seriously polluted and soot blowing is required first.

[0057] S500, controlling the sootblowers corresponding to the heating surfaces to be sootblown to perform sootblowing according to the sootblowing sequence of the heating surfaces to be sootblown.

[0058] In one embodiment, an intelligent soot blowing system can be used to display the status of each heating surface and indicate the soot blowing status, such as Figure 3 As shown, the green circle in the upper left corner of each heated surface in the screen indicates learning mode, which means that historical data is being accumulated; the purple circle indicates use mode, which means that enough data has been learned and it can be put into use; the gray circle in the upper right corner of each heated surface in the screen indicates that it is normal and does not need soot blowing; when the red and gray circles flash alternately, it means that the heated surface needs to be soot blown immediately, while other heated surfaces that need soot blowing will display red.

[0059] In addition, if Figure 4 As shown, in order to better understand the soot blowing conditions of each heating surface, the above-mentioned intelligent soot blowing system also designs a soot blowing frequency statistics page, so that users can better understand the soot blowing conditions of each heating surface, thereby formulating different supervision strategies for different heating surfaces.

[0060] In an embodiment of the present invention, by obtaining the operating parameters required for identifying the low calorific value of coal quality and the pollution rate and the operating parameters required for calculating the heat absorption of the heating surface under the current working condition of the boiler; inputting the operating parameters required for identifying the low calorific value of coal quality and the pollution rate into the pre-constructed exhaust temperature prediction model, the boiler exhaust temperature of each heating surface under the current working condition is obtained; based on the operating parameters required for calculating the low calorific value of coal quality and the heat absorption of the heating surface, the heat transfer coefficient factor of each heating surface under the current working condition is obtained; the heating surface whose boiler exhaust temperature is greater than the preset temperature threshold is determined as the heating surface to be sootblown, and based on the heat transfer coefficient factor of the heating surface to be sootblown, the heating surface to be sootblown is sorted to determine the sootblowing order of the heating surface to be sootblown; according to the sootblowing order of the heating surface to be sootblown, the sootblower corresponding to the heating surface to be sootblown is controlled to perform sootblowing. The present invention can perform sootblowing on the heating surface of the boiler on demand, thereby improving the safety and economy of the unit operation.

[0061] Embodiment 2 Please refer to Figure 5 , Figure 5 2 is a schematic diagram of the structure of a boiler heating surface sootblowing control device provided in an embodiment of the present invention. The boiler heating surface sootblowing control system 200 includes: The data acquisition module 210 is used to obtain the low calorific value of coal quality and the operating parameters required for pollution rate identification and the operating parameters required for heat absorption calculation of the heating surface of the boiler under the current working conditions; The pollution rate identification module 220 is used to input the operating parameters required for coal quality low calorific value and pollution rate identification into a pre-built exhaust gas temperature prediction model to obtain the boiler exhaust gas temperature of each heating surface under the current working condition; The heating surface heat exchange calculation module 230 is used to calculate the required operating parameters based on the low calorific value of the coal quality and the heat absorption of the heating surface, and obtain the heat exchange coefficient factor of each heating surface under the current working condition; A sootblowing determination module 240 is used to determine the heating surface whose boiler exhaust temperature is greater than a preset temperature threshold as the heating surface to be sootblown, and to sort the heating surfaces to be sootblown based on the heat transfer coefficient factors of the heating surfaces to be sootblown, and determine the sootblowing order of the heating surfaces to be sootblown; The sootblowing execution module 250 is used to control the sootblowers corresponding to the heating surfaces to be sootblown to perform sootblowing according to the sootblowing sequence of the heating surfaces to be sootblown.

[0062] It should be understood that the device corresponds to the above-mentioned boiler heating surface sootblowing control method embodiment, and can execute the various steps involved in the above-mentioned method embodiment. The specific functions of the device can be found in the above description. To avoid repetition, the detailed description is appropriately omitted here. The device includes at least one software function module that can be stored in a memory in the form of software or firmware or fixed in the operating system (OS) of the device.

[0063] Embodiment 3 Based on the same inventive concept, an embodiment of the present invention further provides an electronic device, including: a processor and a memory, the memory storing machine-readable instructions executable by the processor, and the machine-readable instructions executing the above-mentioned boiler heating surface sootblowing control method when executed by the processor.

[0064] The memory may include non-permanent memory in a computer-readable medium, random access memory (RAM) and / or non-volatile memory in the form of read-only memory (ROM) or flash RAM. The memory is an example of a computer-readable medium.

[0065] Computer readable media include permanent and non-permanent, removable and non-removable media that can be implemented by any method or technology to store information. Information can be computer readable instructions, data structures, program modules or other data. Examples of computer storage media include, but are not limited to, phase change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technology, compact disk read-only memory (CD-ROM), digital versatile disk (DVD) or other optical storage, magnetic cassettes, magnetic tape magnetic disk storage or other magnetic storage devices or any other non-transmission media that can be used to store information that can be accessed by a computing device. As defined herein, computer readable media does not include temporary computer readable media (transitory media), such as modulated data signals and carrier waves.

[0066] Embodiment 4 Based on the same inventive concept, an embodiment of the present invention further provides a computer-readable storage medium storing computer instructions. When the computer instructions are executed on a computer, the computer executes the above-mentioned boiler heating surface sootblowing control method.

[0067] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application may adopt the form of a computer program product implemented in one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that include computer-usable program code.

[0068] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0069] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0070] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0071] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. To avoid unnecessary repetition, the embodiments of the present invention will not further describe various possible combinations.

[0072] In addition, the functional modules in each embodiment of the present application can be integrated together to form an independent part, or each module can exist separately, or two or more modules can be integrated to form an independent part.

[0073] It should also be noted that the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, commodity or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, commodity or device. In the absence of more restrictions, the elements defined by the sentence "comprises a ..." do not exclude the existence of other identical elements in the process, method, commodity or device including the elements.

[0074] The above are only embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various changes and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included within the scope of the claims of the present application.

Claims

1. A boiler heating surface sootblowing control method, characterized in that: include: Obtain the operating parameters required for the identification of the low calorific value of coal quality and pollution rate and the calculation of the heat absorption of the heating surface under the current working conditions of the boiler; Input the operating parameters required for identifying the low calorific value of coal and the pollution rate into the pre-built exhaust temperature prediction model to obtain the boiler exhaust temperature of each heating surface under the current working conditions; Based on the low calorific value of coal and the heat absorption of the heating surface, the required operating parameters are calculated to obtain the heat transfer coefficient factors of each heating surface under the current working conditions; The heating surfaces whose boiler exhaust gas temperature is greater than a preset temperature threshold are determined as the heating surfaces to be sootblown, and the heating surfaces to be sootblown are sorted based on the heat transfer coefficient factors of the heating surfaces to be sootblown to determine the sootblowing order of the heating surfaces to be sootblown; According to the sootblowing sequence of the heating surface to be sootblown, the sootblowers corresponding to the heating surface to be sootblown are controlled to perform sootblowing.

2. The boiler heating surface sootblowing control method according to claim 1, characterized in that: The calculation rules for low calorific value of coal quality are as follows: ;in, Indicates the low calorific value of coal; represents the coefficient related to efficiency; Indicates the total heat of the boiler; Indicates the amount of coal entering the furnace.

3. The boiler heating surface sootblowing control method according to claim 2, characterized in that: The calculation rule of the total heat of the boiler is: ;in, Indicates the total heat of the boiler; Indicates the effective heat absorption of the boiler; Indicates the total heat of exhaust gas; It indicates the percentage of effective heat absorption of boiler to the total heat of boiler; Indicates exhaust heat loss.

4. The boiler heating surface sootblowing control method according to claim 2, characterized in that: The calculation rule of the total heat of the boiler is: ;in, Indicates the total heat of the boiler; Indicates the effective heat absorption of the boiler; Indicates the total heat of exhaust gas; Indicates heat loss due to incomplete combustion of combustible gas; Indicates heat loss due to incomplete combustion of solids; Indicates heat dissipation loss; Represents the physical heat loss of ash.

5. The boiler heating surface sootblowing control method according to any one of claims 3 or 4, characterized in that: The calculation rule for the effective heat absorption of the boiler is: ;in, Indicates the effective heat absorption of the boiler; Indicates the main steam flow rate; represents the main steam enthalpy; Indicates water supply flow rate; represents the feed water enthalpy; Indicates the cooling water flow rate; represents the reheat steam enthalpy; represents the desuperheating water enthalpy; Indicates the reheat steam flow rate; It represents the exhaust enthalpy of high pressure cylinder; The calculation rule for the total heat of exhaust gas is: ;in, Indicates the total heat of exhaust gas; Indicates exhaust gas temperature; Indicates the reference temperature; Indicates the total air volume.

6. The boiler heating surface sootblowing control method according to claim 4, characterized in that: The calculation rule for heat loss of incomplete combustion of solids is: ;in, Indicates heat loss due to incomplete combustion of solids; Indicates the received ash content of the fuel; It indicates the mass percentage of slag in the total ash of coal; Indicates the mass percentage of carbon in the slag; It indicates the percentage of fly ash content in the total ash content of coal; Indicates the mass percentage of carbon in fly ash; It expresses the boiler heat input per kg of fuel; The calculation rule for heat dissipation loss is: ;in, Indicates heat dissipation loss; Indicates the design value of heat dissipation loss under 100% load; Indicates the amount of boiler fuel; The calculation rule of ash physical heat loss is: ;in, Indicates the physical heat loss of ash; Indicates ash content; Indicates the calorific value of the fuel; Indicates the slag content; Indicates the slag temperature; Indicates the supply air temperature; It indicates the specific heat capacity of slag; Indicates the carbon content of slag; Indicates fly ash content; Indicates exhaust gas temperature; represents the specific heat capacity of fly ash; Indicates fly ash content; Indicates the content of settled ash; Indicates the temperature of settled ash; It represents the specific heat capacity of the settled ash; Indicates the carbon content of settled ash.

7. The boiler heating surface sootblowing control method according to claim 1, characterized in that: The operating parameters required for pollution rate identification include: boiler status, sootblowing operation parameters and particulate emission monitoring data; The operating parameters required for the calculation of heat absorption of the heating surface include: flue gas volume, flue gas enthalpy difference between the inlet and outlet of each heating surface, and the ideal heat transfer capacity of the heating surface.

8. The boiler heating surface sootblowing control method according to claim 7, characterized in that: The pre-built exhaust temperature prediction model is trained in the following way: Obtain the low calorific value of coal quality under different working conditions, the operating parameters required for pollution rate identification, and the actual boiler exhaust temperature of each heating surface of the boiler; Taking the operating parameters required for identifying the low calorific value and pollution rate of coal under different operating conditions as input, the pre-constructed deep learning algorithm model outputs the predicted boiler exhaust temperature of each heating surface of the boiler under different operating conditions, and adjusts the model parameters of the deep learning algorithm model according to the difference between the predicted boiler exhaust temperature of each heating surface of the boiler under different operating conditions and the actual boiler exhaust temperature of each heating surface of the boiler, until the difference between the predicted boiler exhaust temperature of each heating surface of the boiler under different operating conditions output by the deep learning algorithm model and the actual boiler exhaust temperature of each heating surface of the boiler is lower than the preset threshold, so as to obtain the exhaust temperature prediction model.

9. The boiler heating surface sootblowing control method according to claim 7, characterized in that: The calculation rule of the heat transfer coefficient factor of each heating surface is: ;in, Indicates the heat transfer coefficient factor of each heating surface; Indicates the amount of smoke; Indicates the flue gas enthalpy value at the inlet of each heating surface; Indicates the flue gas enthalpy value at the outlet of each heating surface; Represents the ideal heat transfer capacity of each heating surface.

10. The boiler heating surface sootblowing control method according to claim 9, characterized in that: The calculation rule of flue gas volume is: ;in, Indicates the amount of smoke; Indicates the low calorific value of coal; Indicates the CO2 content of flue gas; The calculation rules are: ; Indicates the amount of dry air required for coal combustion; The calculation rules are: ; The calculation rule for the flue gas enthalpy at the inlet of each heating surface is: ;in, Indicates the flue gas enthalpy value at the inlet of each heating surface; , , , , , Indicates the dry air coefficient at the inlet and outlet of the heating surface; represents the flue gas temperature at the inlet of the i-th heating surface; , , , , Indicates the water vapor coefficient at the inlet and outlet of the heating surface; , , , , Indicates the carbon dioxide coefficient at the inlet and outlet of the heating surface; The calculation rule for the flue gas enthalpy at the outlet of each heating surface is: ;in, Indicates the flue gas enthalpy value at the outlet of each heating surface; The flue gas temperature at the outlet of the i+1th heating surface.

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