Air preheater air leakage monitoring method and device

Abstract

The application provides an air preheater air leakage monitoring method and device, the method comprises the following steps: when the boiler is running in a stable output condition, obtaining the boiler fan parameters, the fan current and the boiler output corresponding to the stable output condition; according to the boiler fan parameters, the fan current and the boiler output corresponding to the stable output condition, using a preset air leakage relationship fitting model to obtain the theoretical air leakage rate and the actual air leakage rate of the air preheater; comparing the actual air leakage rate with the theoretical air leakage rate of the air preheater to obtain an air leakage rate difference value, comparing the air leakage rate difference value with a preset threshold value to obtain a difference comparison result; and determining the air preheater air leakage monitoring result according to the difference comparison result. The application accurately determines the theoretical air leakage rate and the actual air leakage rate of the air preheater, thereby obtaining the air preheater air leakage rate difference value, and accurately monitors the air preheater air leakage condition through the change of the air leakage rate, so as to quantitatively analyze the evolution of the air preheater air leakage rate.

Description

Technical Field

[0001] This invention relates to the field of air preheater technology, and more particularly to a method and device for monitoring air leakage in an air preheater. Background Technology

[0002] Air leakage rate is an important performance indicator for air preheaters, reflecting their sealing performance; a lower leakage rate indicates better sealing performance. Although air leakage has little impact on the heat exchange capacity of the air preheater itself, an increased leakage rate leads to increased energy loss in the boiler fan. Therefore, accurately monitoring the air leakage rate of the air preheater is a crucial prerequisite for effective boiler energy conservation.

[0003] Existing technical solutions include those based on the principle of conservation of specific components in the inlet and outlet flue gas, namely the daily leakage rate monitoring method recommended in the air preheater performance test procedures. This method is suitable for air preheater leakage rate tests under grid-based flue gas component measurement conditions. Besides using oxygen concentration in the flue gas as a characteristic component, the concentration of other components (such as nitrogen oxides, carbon dioxide, etc.) can also be used as characteristic components to calculate the leakage rate. Problems with this solution include: the accuracy of flue gas component concentration measurement greatly affects the final result; when the measurement point deviation is too large, counterintuitive results may occur. For example, when the oxygen content at the air preheater outlet is less than the oxygen content at the inlet, the calculated leakage rate is negative; when the oxygen content at the air preheater outlet is large, the calculated leakage rate exceeds 50%. When applied to online monitoring, this solution is mainly limited by the insufficient number of flue gas component measurement points (or the measurement points themselves are inaccurate). A few counterintuitive results will severely reduce the reliability of the entire system.

[0004] Existing technical solutions also include a daily leakage rate monitoring method based on the principle of conservation of total energy of inlet and outlet fluids, which offers higher accuracy than the flue gas composition method and is suitable for monitoring air preheater leakage rates when the number of online measuring points is limited. It uses the inlet and outlet flue gas temperature and air temperature of the air preheater as the main basic data, supplemented by flue gas static pressure data. Due to the relatively high reliability of temperature and static pressure measuring points, the calculated leakage rate can well reflect the performance change trend of the air preheater. The problems with this solution include: the use of a large variety of basic data, the results being mainly affected by changes in air preheater heat dissipation, and the need for periodic calibration of the calculation results through standardized performance tests.

[0005] Existing technical solutions also include the principle of mass conservation of inlet and outlet fluids, which is another method suitable for online monitoring of air leakage rate. It uses the flue gas and air flow rates at the inlet and outlet of the air preheater as the main basic data, directly conforming to the physical definition of air leakage rate, and the calculated air leakage rate can reflect the performance change trend of the air preheater relatively well. Problems with this solution include: if the flue gas and air flow rates are directly measured using flow measurement points, the measurement error is large, and the reliability of the measurement points is also poor. If the flue gas and air flow rates are estimated using fuel composition, the real-time monitoring is difficult to guarantee when the fuel changes. Summary of the Invention

[0006] To address the problems existing in the prior art, the main objective of this invention is to provide an air preheater leakage monitoring method and device to accurately monitor the air preheater leakage.

[0007] To achieve the above objectives, embodiments of the present invention provide a method for monitoring air leakage in an air preheater, the method comprising:

[0008] When the boiler is operating under stable output conditions, obtain the boiler fan parameters, fan current and boiler output corresponding to the stable output conditions.

[0009] Based on the boiler fan parameters, fan current and boiler output corresponding to stable output conditions, the theoretical air leakage rate and actual air leakage rate of the air preheater are obtained by using a preset air leakage relationship fitting model.

[0010] The actual air leakage rate of the air preheater is compared with the theoretical air leakage rate to obtain the air leakage rate difference value, and the air leakage rate difference value is compared with the preset threshold to obtain the difference comparison result.

[0011] Based on the difference comparison results, the air preheater leakage monitoring results were determined.

[0012] Optionally, in one embodiment of the present invention, the air leakage relationship fitting model is established through the following steps:

[0013] Under multiple preset boiler reference operating conditions, the average oxygen content of the inlet flue gas section and the average oxygen content of the outlet flue gas section of the air preheater are obtained.

[0014] The theoretical air leakage rate corresponding to the baseline operating conditions of each boiler is determined based on the average oxygen content of the inlet flue gas section and the average oxygen content of the outlet flue gas section.

[0015] Based on the obtained boiler gas static pressure, boiler gas temperature and fan current corresponding to each boiler's reference operating condition, determine the current characteristic parameters corresponding to each boiler's reference operating condition.

[0016] The boiler output, current characteristic parameters, and theoretical air leakage rate corresponding to the benchmark operating conditions of each boiler are fitted to obtain the air leakage relationship fitting model.

[0017] Optionally, in one embodiment of the present invention, based on the boiler fan parameters, fan current, and boiler output corresponding to stable output conditions, a preset air leakage relationship fitting model is used to obtain the theoretical and actual air leakage rates of the air preheater, including:

[0018] The boiler output corresponding to the stable output condition is input into the air leakage relationship fitting model to obtain the current characteristic parameters and theoretical air leakage rate corresponding to the stable output condition.

[0019] The actual air leakage rate of the air preheater is obtained based on the current characteristic parameters, fan current, and boiler gas static pressure, boiler gas temperature, and boiler gas flow rate in the boiler fan parameters corresponding to stable output conditions.

[0020] Optionally, in one embodiment of the present invention, determining the air preheater leakage monitoring result based on the difference comparison result includes:

[0021] If the difference comparison result is that the difference in air leakage rate is not less than the preset threshold, then the stable output condition is determined to be an abnormal condition.

[0022] Based on the preset abnormal operating condition judgment rules, the abnormal operating conditions are statistically analyzed to determine the air preheater leakage monitoring results.

[0023] This invention also provides an air preheater leakage monitoring device, the device comprising:

[0024] The data acquisition module is used to acquire the boiler fan parameters, fan current and boiler output corresponding to the stable output condition when the boiler is operating under stable output conditions.

[0025] The air leakage rate module is used to obtain the theoretical and actual air leakage rates of the air preheater by using a preset air leakage relationship fitting model based on the boiler fan parameters, fan current and boiler output under stable output conditions.

[0026] The difference comparison module is used to compare the actual air leakage rate of the air preheater with the theoretical air leakage rate to obtain the air leakage rate difference value, and compare the air leakage rate difference value with a preset threshold to obtain the difference comparison result.

[0027] The monitoring results module is used to determine the air preheater leakage monitoring results based on the difference comparison results.

[0028] Optionally, in one embodiment of the present invention, the apparatus further includes:

[0029] The oxygen content module is used to obtain the average oxygen content of the inlet flue gas section and the average oxygen content of the outlet flue gas section of the air preheater under multiple preset boiler reference operating conditions.

[0030] The theoretical value module is used to determine the theoretical air leakage rate corresponding to the benchmark operating conditions of each boiler based on the average oxygen content of the inlet flue gas section and the average oxygen content of the outlet flue gas section.

[0031] The feature parameter module is used to determine the current feature parameters corresponding to each boiler reference operating condition based on the obtained boiler gas static pressure, boiler gas temperature and fan current.

[0032] The fitting model module is used to fit the boiler output, current characteristic parameters and theoretical air leakage rate corresponding to the benchmark operating conditions of each boiler to obtain the air leakage relationship fitting model.

[0033] Optionally, in one embodiment of the present invention, the air leakage rate module includes:

[0034] The feature parameter unit is used to input the boiler output corresponding to the stable output condition into the air leakage relationship fitting model to obtain the current feature parameters and theoretical air leakage rate corresponding to the stable output condition.

[0035] The air leakage rate unit is used to obtain the actual air leakage rate of the air preheater based on the current characteristic parameters, fan current, and boiler gas static pressure, boiler gas temperature, and boiler gas flow rate in the boiler fan parameters corresponding to stable output conditions.

[0036] Optionally, in one embodiment of the present invention, the measurement result module includes:

[0037] The abnormal operating condition unit is used to determine that the stable output operating condition is an abnormal operating condition if the difference comparison result is that the difference in air leakage rate is not less than a preset threshold.

[0038] The monitoring results unit is used to perform data statistics on abnormal operating conditions according to preset abnormal operating condition judgment rules, and to determine the air preheater leakage monitoring results.

[0039] The present invention also provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the above-described method.

[0040] The present invention also provides a computer-readable storage medium storing a computer program that performs the above-described methods by a computer.

[0041] The present invention also provides a computer program product, including a computer program / instructions, which, when executed by a processor, implement the steps of the above-described method.

[0042] This invention solves the problem of monitoring the air leakage performance of air preheaters using online measuring points. Under complex equipment and system operating conditions, it uses highly reliable online measuring points to obtain relevant boiler data, accurately determine the theoretical and actual air leakage rates of the air preheater, and thus obtain the difference value of the air preheater's air leakage rate. By observing the changes in the air leakage rate, it is possible to accurately monitor the air leakage of the air preheater, so as to quantitatively analyze the evolution of the air preheater's air leakage rate. Attached Figure Description

[0043] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0044] Figure 1 This is a flowchart of an air preheater leakage monitoring method according to an embodiment of the present invention;

[0045] Figure 2 This is a flowchart illustrating the process of establishing a leakage relationship fitting model in an embodiment of the present invention;

[0046] Figure 3 This is a flowchart for determining the air leakage rate in an embodiment of the present invention;

[0047] Figure 4 This is a flowchart illustrating the process of determining the air preheater leakage monitoring results in an embodiment of the present invention;

[0048] Figure 5 This is a flowchart of air preheater leakage monitoring in a specific embodiment of the present invention;

[0049] Figure 6 This is a schematic diagram showing the output of air preheater leakage results in an embodiment of the present invention;

[0050] Figure 7 This is a schematic diagram of the structure of an air preheater leakage monitoring device according to an embodiment of the present invention;

[0051] Figure 8 This is a schematic diagram of the air preheater leakage monitoring device in another embodiment of the present invention;

[0052] Figure 9 This is a schematic diagram of the air leakage rate module in an embodiment of the present invention;

[0053] Figure 10 This is a schematic diagram of the monitoring result module in an embodiment of the present invention;

[0054] Figure 11This is a schematic diagram of the structure of an electronic device provided in an embodiment of the present invention. Detailed Implementation

[0055] This invention provides a method and apparatus for monitoring air leakage in an air preheater.

[0056] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0057] like Figure 1 The diagram shows a flowchart of an air preheater leakage monitoring method according to an embodiment of the present invention. The execution subject of the air preheater leakage monitoring method provided in this embodiment includes, but is not limited to, a computer. This invention solves the problem of monitoring air preheater leakage performance using online measuring points. Under complex equipment and system operating conditions, it utilizes highly reliable online measuring points to obtain relevant boiler data, accurately determining the theoretical and actual leakage rates of the air preheater. This yields the difference in the air preheater leakage rate, and the changes in the leakage rate enable accurate monitoring of the air preheater's leakage status, facilitating quantitative analysis of the evolution of the air preheater leakage rate. The method shown in the diagram includes:

[0058] Step S1: When the boiler is operating under stable output conditions, obtain the boiler fan parameters, fan current and boiler output corresponding to the stable output conditions.

[0059] Step S2: Based on the boiler fan parameters, fan current and boiler output corresponding to the stable output condition, the theoretical air leakage rate and actual air leakage rate of the air preheater are obtained by using the preset air leakage relationship fitting model.

[0060] Step S3: Compare the actual air leakage rate of the air preheater with the theoretical air leakage rate to obtain the air leakage rate difference value, and compare the air leakage rate difference value with a preset threshold to obtain the difference comparison result.

[0061] Step S4: Determine the air preheater leakage monitoring results based on the difference comparison results.

[0062] An air preheater is a heat exchanger that uses the waste heat from the flue gas discharged from the boiler to heat the air entering the boiler. Because the static pressure of the flue gas is less than atmospheric pressure and the static pressure of the air is greater than atmospheric pressure, the static pressure difference drives air to mix into the flue gas through its gaps (or leaks), a phenomenon known as air preheater leakage.

[0063] In addition, the air leakage rate refers to the mass ratio of the amount of air leaking into the flue gas to the amount of flue gas at the inlet of the air preheater, usually expressed as a percentage, in units of %.

[0064] Among them, the boiler operating under stable output conditions is the boiler's benchmark operating condition. Taking a boiler with a stable operating output range of 30%-100% of its rated output as an example, five benchmark operating conditions can be selected: 30%, 40%, 55%, 75%, and 100%.

[0065] Specifically, when the boiler is operating under stable output conditions, the boiler fan parameters, fan current, and boiler output corresponding to these conditions are acquired. This is achieved by setting up monitoring points on the boiler to collect data, which will not be elaborated further here.

[0066] Specifically, the fan current includes the current of the boiler primary air fan, forced draft fan, and induced draft fan.

[0067] Furthermore, the preset air leakage relationship fitting model shows the fitting relationship between the air leakage rate and the boiler output. Therefore, by substituting the boiler fan parameters, fan current and boiler output corresponding to the stable output condition into the air leakage relationship fitting model, the theoretical air leakage rate and the actual air leakage rate of the air preheater can be obtained.

[0068] Specifically, by using a leakage relationship fitting model to calculate data such as fan current, the current characteristic parameters and the theoretical leakage rate of the air preheater can be obtained. Then, based on the current characteristic parameters, the actual leakage rate of the air preheater can be calculated.

[0069] Furthermore, by comparing the actual air leakage rate of the air preheater with the theoretical air leakage rate, the difference comparison result can be obtained. Specifically, the difference between the actual air leakage rate and the theoretical air leakage rate is first calculated, and then the ratio of the difference to the theoretical air leakage rate is calculated. The resulting difference value is the difference comparison result.

[0070] Furthermore, the difference comparison results are compared with a preset threshold. If the difference in air leakage rate is not less than the preset threshold, the stable output condition is determined to be an abnormal condition. At this time, relevant data under the abnormal condition are collected or calculated, including the number of abnormal conditions, the boiler output range covered by the abnormal conditions, the time interval of the abnormal conditions, the dispersion of the difference comparison results, etc. After statistical analysis of these relevant data, the air preheater leakage monitoring results can be determined.

[0071] Specifically, the air preheater leakage monitoring results can show the changes in the leakage rate. Therefore, the air preheater leakage monitoring results are sent to the terminal in the form of statistical charts for display, so that the staff can handle the relevant abnormal conditions and improve the efficiency of abnormal condition handling.

[0072] As one embodiment of the present invention, such as Figure 2 As shown, the air leakage relationship fitting model is established through the following steps:

[0073] Step S5: Under multiple preset boiler reference operating conditions, obtain the average oxygen content of the inlet flue gas section and the average oxygen content of the outlet flue gas section of the air preheater.

[0074] Step S6: Determine the theoretical air leakage rate corresponding to the baseline operating conditions of each boiler based on the average oxygen content of the inlet flue gas section and the average oxygen content of the outlet flue gas section.

[0075] Step S7: Based on the obtained boiler gas static pressure, boiler gas temperature and fan current corresponding to each boiler reference operating condition, determine the current characteristic parameters corresponding to each boiler reference operating condition.

[0076] Step S8: Fit the boiler output, current characteristic parameters and theoretical air leakage rate corresponding to the reference operating conditions of each boiler to obtain the air leakage relationship fitting model.

[0077] For example, taking a boiler that can still operate stably under multiple preset boiler reference conditions with an output range of 30%-100% of its rated output as an example, five reference conditions can be selected: 30%, 40%, 55%, 75%, and 100%. The average oxygen content of the flue gas cross-sections at the inlet and outlet of the air preheater was tested using the grid method, which will not be elaborated here.

[0078] Furthermore, by utilizing the average oxygen content of the inlet flue gas cross section and the average oxygen content of the outlet flue gas cross section, the theoretical air leakage rate corresponding to the baseline operating conditions of each boiler can be calculated.

[0079] Furthermore, conventional methods were used to collect boiler gas static pressure, boiler gas temperature, and fan current corresponding to the baseline operating conditions of each boiler. The boiler output, current characteristic parameters, and theoretical air leakage rate corresponding to the baseline operating conditions of each boiler were then fitted to obtain a fitting model for the air leakage relationship.

[0080] It should be noted that historical data can be used in the process of fitting the air leakage relationship model, which is different from the real-time data used to determine the air preheater leakage monitoring results in steps S1-S4.

[0081] As one embodiment of the present invention, such as Figure 3 As shown, based on the boiler fan parameters, fan current, and boiler output under stable output conditions, and using a pre-set leakage relationship fitting model, the theoretical and actual leakage rates of the air preheater are obtained, including:

[0082] Step S21: Input the boiler output corresponding to the stable output condition into the air leakage relationship fitting model to obtain the current characteristic parameters and theoretical air leakage rate corresponding to the stable output condition.

[0083] Step S22: Based on the current characteristic parameters, fan current, and boiler gas static pressure, boiler gas temperature, and boiler gas flow rate in the boiler fan parameters corresponding to the stable output condition, the actual air leakage rate of the air preheater is obtained.

[0084] The preset air leakage relationship fitting model shows the fitting relationship between the air leakage rate and the boiler output. Therefore, by substituting the boiler fan parameters, fan current and boiler output corresponding to the stable output condition into the air leakage relationship fitting model, the theoretical air leakage rate and the actual air leakage rate of the air preheater can be obtained.

[0085] Furthermore, by using a leakage relationship fitting model to calculate data such as fan current, the current characteristic parameters and the theoretical leakage rate of the air preheater can be obtained. Then, based on the current characteristic parameters, the actual leakage rate of the air preheater can be calculated.

[0086] As one embodiment of the present invention, such as Figure 4 As shown, based on the difference comparison results, the air preheater leakage monitoring results include:

[0087] Step S41: If the difference comparison result is that the difference in air leakage rate is not less than the preset threshold, then the stable output condition is determined to be an abnormal condition.

[0088] Step S42: Perform data statistics on abnormal operating conditions according to the preset abnormal operating condition judgment rules, and determine the air preheater leakage monitoring results.

[0089] The difference comparison result is compared with the preset threshold. If the difference in leakage rate is not less than the preset threshold, the stable output condition is determined to be an abnormal condition.

[0090] At this point, relevant data under the abnormal operating condition are collected or calculated, including the number of abnormal operating conditions, the boiler output range covered by the abnormal operating conditions, the time interval of the abnormal operating conditions, the dispersion of the difference comparison results, etc. After statistical analysis of these relevant data, the air preheater leakage monitoring results can be determined.

[0091] In a specific embodiment of the present invention, such as Figure 5 As shown, the air preheater leakage monitoring process mainly includes: 1) determining the baseline operating conditions; 2) testing and calibrating the leakage rate; 3) establishing a baseline database; 4) recording abnormal operating conditions; and 5) judging and outputting the evolution results.

[0092] 1) Determine the baseline operating condition

[0093] The typical stable operating output of the boiler should be used as the benchmark operating condition. The benchmark operating condition should cover the common operating output range of the boiler. There should be no fewer than three benchmark operating conditions.

[0094] 2) Test and calibrate the air leakage rate

[0095] When the boiler is running stably at the reference operating point, a leakage rate test is carried out in accordance with standard procedures to obtain the reference value of the leakage rate and other characteristic parameter values ​​corresponding to this operating condition.

[0096] 3) Establish a benchmark database

[0097] The leakage rate and characteristic parameters of the benchmark operating points are integrated into a benchmark database for daily calculations. That is, a leakage relationship fitting model is pre-established to facilitate use in practical applications.

[0098] 4) Record abnormal operating conditions

[0099] A leakage relationship fitting model was used to identify and process real-time operating data from the boiler and air preheater. The processed results were compared with baseline data to obtain their quantitative differences. Data with differences exceeding the allowable error range were recorded as abnormal operating conditions.

[0100] 5) Determine and output the evolution results.

[0101] The system records abnormal operating conditions according to the set rules and outputs the results in a user-friendly manner.

[0102] In this embodiment, the air preheater leakage monitoring process is described in detail below.

[0103] (1) Taking a boiler with a stable operating output range of 30%-100% of the rated output as an example, five benchmark operating conditions can be selected: 30%, 40%, 55%, 75%, and 100%.

[0104] (2) The test method for the air preheater leakage rate under the reference operating conditions is as follows:

[0105] The average oxygen content (O2) at the inlet and outlet flue gas cross sections of the air preheater was measured using the grid method. en O lv The air preheater leakage rate, i.e., the theoretical leakage rate, is calculated according to the following formula:

[0106]

[0107] (3) The selection of feature parameters can include, but is not limited to, the following methods:

[0108] Based on the current E of the primary air fan, forced draft fan, and induced draft fan pa E sa and E id That is, the fan current, to calculate the characteristic parameters corresponding to the baseline operating condition. and That is, the current characteristic parameters.

[0109]

[0110] Where n is the power exponent, and 1 <n≤3;t pa t sa and t id These are the primary air, supply air, and flue gas temperatures under baseline operating conditions, obtained through online flue gas and air temperature measurement points; t pa t sa and t id These represent the primary air, supply air, and flue gas static pressure under baseline operating conditions, obtained through online flue gas pressure measurement points. 100 is expressed as a percentage, and is related to the efficiency η1. * Units are consistent; 273 represents a temperature of 273 K; 101325 represents an atmospheric pressure of 101325 Pa.

[0111] Furthermore, The relationship between (denoted as y) and boiler output (denoted as x) is fitted to polynomial functions, i.e., the air leakage relationship fitting model:

[0112]

[0113] Where n is the order of the polynomial function, n≥2. i These are the polynomial coefficients. When the boiler is operating under any steady-state condition, the boiler output x can be calculated from this fitting function.

[0114] (4) When the boiler is in a stable output condition, first calculate the boiler output x corresponding to that condition. (Theoretical air leakage rate) Further calculation of the actual air leakage rate η of the air preheater. l .

[0115]

[0116]

[0117]

[0118]

[0119]

[0120] Where, η id γ1 represents the flue gas leakage rate; γ2 and γ1 represent the primary air and supply air flow rates, respectively; E pa E sa and E id These represent the currents of the primary air fan, forced draft fan, and induced draft fan under this operating condition; η a The leakage rate of primary air and supply air; t pa tsa and t id These are the primary air, supply air, and flue gas temperatures under this operating condition, i.e., the boiler gas temperature, obtained through online flue gas temperature measurement points; t pa t sa and t id These represent the static pressure of the primary air, supply air, and flue gas under this operating condition, i.e., the boiler gas static pressure, obtained through online air and flue gas pressure measuring points. m1 and m2 represent the primary air and supply air flow rates, i.e., the boiler gas flow rates, obtained through online air volume measuring points.

[0121] Furthermore, calculate the air leakage rate η. l and Differences:

[0122]

[0123] If |Δη|≥10% (10% is a set value, i.e., a preset threshold, or other constants or functions ≥5%), then the working condition is determined to be an abnormal working condition, and the difference between the boiler output x and the air leakage rate Δη under the abnormal working condition is recorded.

[0124] (5) When the abnormal operating condition record meets one or more of the following conditions, the relevant data under the abnormal operating condition shall be collected to determine the change in the air preheater leakage rate, i.e., the air preheater leakage monitoring result:

[0125] ① The number of abnormal operating conditions is ≥ k (k≥3)

[0126] ② The boiler output range covered by abnormal operating conditions is ≥ω (ω≥30% of rated load).

[0127] ③ The time interval of abnormal operating conditions is ≤ T (T≤ 168 hours)

[0128] ④ The dispersion of the air leakage rate difference Δη under abnormal operating conditions is ≤Ф (Ф≤20%).

[0129] (6) Output the air preheater leakage monitoring results in a user-friendly manner, including but not limited to the following methods:

[0130] Adopting such Figure 6 The image shows a visual representation of the air preheater. White arrows indicate flue gas flow direction, and arrow width indicates flue gas volume; black arrows indicate air flow direction, and arrow width indicates air volume; white arrows with dotted lines indicate air leakage direction, arrow width indicates air leakage rate, and the edge of the dotted line indicates the design upper limit of air leakage rate.

[0131] This invention solves the problems of monitoring air leakage performance of air preheaters using online measuring points, including the low reliability of flue gas composition measuring points; large deviation in calculating the air leakage rate based on the oxygen content in the flue gas; and the long time consumption of analyzing the elemental composition of the fuel entering the furnace.

[0132] This invention utilizes highly reliable online measuring points to obtain boiler-related data under complex equipment and system operating conditions, accurately determining the theoretical and actual air leakage rates of the air preheater. This yields the difference in the air preheater's air leakage rate, enabling accurate monitoring of the air preheater's leakage status through changes in the leakage rate, thus facilitating quantitative analysis of the evolution of the air preheater's air leakage rate.

[0133] like Figure 7 The figure shows a schematic diagram of an air preheater leakage monitoring device according to an embodiment of the present invention. The device shown in the figure includes:

[0134] The data acquisition module 10 is used to acquire the boiler fan parameters, fan current and boiler output corresponding to the stable output condition when the boiler is operating under stable output conditions.

[0135] The air leakage rate module 20 is used to obtain the theoretical air leakage rate and the actual air leakage rate of the air preheater by using a preset air leakage relationship fitting model based on the boiler fan parameters, fan current and boiler output corresponding to the stable output conditions.

[0136] The difference comparison module 30 is used to compare the actual air leakage rate of the air preheater with the theoretical air leakage rate to obtain the air leakage rate difference value, and compare the air leakage rate difference value with a preset threshold to obtain the difference comparison result.

[0137] The monitoring results module 40 is used to determine the air preheater leakage monitoring results based on the difference comparison results.

[0138] As one embodiment of the present invention, such as Figure 8 As shown, the device also includes:

[0139] The oxygen content module 50 is used to obtain the average oxygen content of the inlet flue gas section and the average oxygen content of the outlet flue gas section of the air preheater under multiple preset boiler reference operating conditions.

[0140] The theoretical value module 60 is used to determine the theoretical air leakage rate corresponding to the benchmark operating conditions of each boiler based on the average oxygen content of the inlet flue gas section and the average oxygen content of the outlet flue gas section.

[0141] The feature parameter module 70 is used to determine the current feature parameters corresponding to each boiler reference operating condition based on the obtained boiler gas static pressure, boiler gas temperature and fan current.

[0142] The fitting model module 80 is used to fit the boiler output, current characteristic parameters and theoretical air leakage rate corresponding to the benchmark operating conditions of each boiler to obtain the air leakage relationship fitting model.

[0143] As one embodiment of the present invention, such as Figure 9As shown, the air leakage rate module 20 includes:

[0144] The feature parameter unit 21 is used to input the boiler output corresponding to the stable output condition into the air leakage relationship fitting model to obtain the current feature parameters and theoretical air leakage rate corresponding to the stable output condition.

[0145] The air leakage rate unit 22 is used to obtain the actual air leakage rate of the air preheater based on the current characteristic parameters, fan current, and boiler gas static pressure, boiler gas temperature, and boiler gas flow rate in the boiler fan parameters corresponding to the stable output operating conditions.

[0146] As one embodiment of the present invention, such as Figure 10 As shown, the monitoring results module 40 includes:

[0147] Abnormal operating condition unit 41 is used to determine that the stable output operating condition is an abnormal operating condition if the difference comparison result is that the difference value of the air leakage rate is not less than a preset threshold.

[0148] The monitoring result unit 42 is used to perform data statistics on abnormal operating conditions according to the preset abnormal operating condition judgment rules, and to determine the air preheater leakage monitoring results.

[0149] Based on the same concept as the aforementioned air preheater leakage monitoring method, this invention also provides an air preheater leakage monitoring device. Since the principle by which this air preheater leakage monitoring device solves the problem is similar to that of the air preheater leakage monitoring method, the implementation of this air preheater leakage monitoring device can refer to the implementation of the air preheater leakage monitoring method; repeated details will not be elaborated further.

[0150] This invention solves the problem of monitoring the air leakage performance of air preheaters using online measuring points. Under complex equipment and system operating conditions, it uses highly reliable online measuring points to obtain relevant boiler data, accurately determine the theoretical and actual air leakage rates of the air preheater, and thus obtain the difference value of the air preheater's air leakage rate. By observing the changes in the air leakage rate, it is possible to accurately monitor the air leakage of the air preheater, so as to quantitatively analyze the evolution of the air preheater's air leakage rate.

[0151] The present invention also provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the above-described method.

[0152] The present invention also provides a computer program product, including a computer program / instructions, which, when executed by a processor, implement the steps of the above-described method.

[0153] The present invention also provides a computer-readable storage medium storing a computer program that performs the above-described methods by a computer.

[0154] like Figure 11 As shown, the electronic device 600 may also include: a communication module 110, an input unit 120, an audio processor 130, a display 160, and a power supply 170. It is worth noting that the electronic device 600 does not necessarily need to include these components. Figure 11 All components shown; in addition, the electronic device 600 may also include Figure 11 For components not shown, please refer to existing technology.

[0155] like Figure 11 As shown, the central processing unit 100, sometimes also referred to as a controller or operating control, may include a microprocessor or other processor device and / or logic device. The central processing unit 100 receives inputs and controls the operation of various components of the electronic device 600.

[0156] The memory 140 may be, for example, one or more of a cache, flash memory, hard drive, removable media, volatile memory, non-volatile memory, or other suitable devices. It may store the aforementioned failure-related information, and also store a program for executing that information. The central processing unit 100 may execute the program stored in the memory 140 to perform information storage or processing, etc.

[0157] Input unit 120 provides input to central processing unit 100. Input unit 120 may be, for example, a keypad or touch input device. Power supply 170 provides power to electronic device 600. Display 160 displays images and text. Display may be, for example, an LCD display, but is not limited thereto.

[0158] The memory 140 can be a solid-state memory, such as a read-only memory (ROM), random access memory (RAM), a SIM card, etc. It can also be a memory that retains information even when power is off, can be selectively erased, and contains more data; examples of this type of memory are sometimes referred to as EPROMs. The memory 140 can also be some other type of device. The memory 140 includes a buffer memory 141 (sometimes referred to as a buffer). The memory 140 may include an application / function storage unit 142 for storing application programs and function programs or processes for executing the operation of the electronic device 600 via the central processing unit 100.

[0159] The memory 140 may also include a data storage unit 143 for storing data, such as contacts, digital data, pictures, sounds, and / or any other data used by the electronic device. The driver storage unit 144 of the memory 140 may include various drivers for the electronic device's communication functions and / or for performing other functions of the electronic device (such as messaging applications, address book applications, etc.).

[0160] The communication module 110 is a transmitter / receiver 110 that transmits and receives signals via antenna 111. The communication module (transmitter / receiver) 110 is coupled to the central processing unit 100 to provide input signals and receive output signals, which can be the same as in a conventional mobile communication terminal.

[0161] Based on different communication technologies, multiple communication modules 110 can be configured in the same electronic device, such as cellular network modules, Bluetooth modules, and / or wireless LAN modules. The communication module (transmitter / receiver) 110 is also coupled to a speaker 131 and a microphone 132 via an audio processor 130 to provide audio output via the speaker 131 and receive audio input from the microphone 132, thereby enabling typical telecommunications functions. The audio processor 130 may include any suitable buffer, decoder, amplifier, etc. Additionally, the audio processor 130 is coupled to a central processing unit 100, enabling on-device recording via the microphone 132 and on-device playback of stored audio via the speaker 131.

[0162] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0163] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1A device that provides the functions specified in one or more boxes.

[0164] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0165] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0166] Specific embodiments have been used to illustrate the principles and implementation methods of this invention. The descriptions of the embodiments above are only for the purpose of helping to understand the method and core ideas of this invention. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of this invention. Therefore, the content of this specification should not be construed as a limitation of this invention.

Claims

1. A method for monitoring air leakage in an air preheater, characterized in that, The method includes: Under multiple preset boiler reference operating conditions, the average oxygen content of the inlet flue gas section and the average oxygen content of the outlet flue gas section of the air preheater are obtained. Based on the average oxygen content of the inlet flue gas cross section and the average oxygen content of the outlet flue gas cross section, determine the theoretical air leakage rate corresponding to the baseline operating conditions of each boiler. Based on the obtained boiler gas static pressure, boiler gas temperature and fan current corresponding to each boiler's baseline operating condition, determine the current characteristic parameters corresponding to each boiler's baseline operating condition; the fan current includes: primary air fan current, forced draft fan current and induced draft fan current. The boiler output, current characteristic parameters and theoretical air leakage rate corresponding to the benchmark operating conditions of each boiler are fitted to obtain the air leakage relationship fitting model. When the boiler is operating under stable output conditions, obtain the boiler fan parameters, fan current and boiler output corresponding to the stable output conditions. The boiler output corresponding to the stable output condition is input into the air leakage relationship fitting model to obtain the current characteristic parameters and theoretical air leakage rate corresponding to the stable output condition. Based on the current characteristic parameters, fan current, and boiler gas static pressure, boiler gas temperature, and boiler gas flow rate in the boiler fan parameters corresponding to stable output conditions, the actual air leakage rate of the air preheater is obtained. The actual air leakage rate of the air preheater is compared with the theoretical air leakage rate to obtain the air leakage rate difference value, and the air leakage rate difference value is compared with a preset threshold to obtain the difference comparison result. Based on the comparison results, the air preheater leakage monitoring results are determined.

2. The method according to claim 1, characterized in that, Based on the comparison results, the air preheater leakage monitoring results are determined to include: If the difference comparison result is that the air leakage rate difference value is not less than a preset threshold, then the stable output condition is determined to be an abnormal condition. Based on the preset abnormal operating condition judgment rules, the abnormal operating conditions are statistically analyzed to determine the air preheater leakage monitoring results.

3. An air preheater leakage monitoring device, characterized in that, The device includes: The oxygen content module is used to obtain the average oxygen content of the inlet flue gas section and the average oxygen content of the outlet flue gas section of the air preheater under multiple preset boiler reference operating conditions. The theoretical value module is used to determine the theoretical air leakage rate corresponding to the benchmark operating conditions of each boiler based on the average oxygen content of the inlet flue gas section and the average oxygen content of the outlet flue gas section. The feature parameter module is used to determine the current feature parameters corresponding to each boiler reference operating condition based on the obtained boiler gas static pressure, boiler gas temperature and fan current; the fan current includes: primary air fan current, forced draft fan current and induced draft fan current. The fitting model module is used to fit the boiler output, current characteristic parameters and theoretical air leakage rate corresponding to the benchmark operating conditions of each boiler to obtain the air leakage relationship fitting model. The data acquisition module is used to acquire the boiler fan parameters, fan current and boiler output corresponding to the stable output condition when the boiler is operating under stable output conditions. The air leakage rate module is used to obtain the theoretical and actual air leakage rates of the air preheater based on the boiler fan parameters, fan current, and boiler output corresponding to the stable output condition, using a preset air leakage relationship fitting model. The air leakage rate module includes: a feature parameter unit, used to input the boiler output corresponding to the stable output condition into the air leakage relationship fitting model to obtain the current feature parameters and theoretical air leakage rate corresponding to the stable output condition; and an air leakage rate unit, used to obtain the actual air leakage rate of the air preheater based on the current feature parameters, fan current, and boiler gas static pressure, boiler gas temperature, and boiler gas flow rate from the boiler fan parameters corresponding to the stable output condition. The difference comparison module is used to compare the actual air leakage rate of the air preheater with the theoretical air leakage rate to obtain the air leakage rate difference value, and compare the air leakage rate difference value with a preset threshold to obtain the difference comparison result. The monitoring results module is used to determine the air preheater leakage monitoring results based on the difference comparison results.

4. The apparatus according to claim 3, characterized in that, The monitoring result module includes: An abnormal operating condition unit is used to determine that a stable output operating condition is an abnormal operating condition if the difference comparison result is that the difference in air leakage rate is not less than a preset threshold. The monitoring results unit is used to perform data statistics on abnormal operating conditions according to preset abnormal operating condition judgment rules, and to determine the air preheater leakage monitoring results.

5. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements the method of claim 1 or 2.

6. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program that enables a computer to perform the method of claim 1 or 2.

7. A computer program product comprising a computer program / instructions, characterized in that, When the computer program / instructions are executed by the processor, they implement the steps of the method of claim 1 or 2.

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