A method and device for comprehensive evaluation of boiler performance

Abstract

The present application discloses a method and device for comprehensive evaluation of boiler performance, the method comprising: before deep peak regulation, iterative calculation is performed by dividing the water-cooled wall tube into micro-element tube segments to obtain the water-cooled wall tube flow and water-cooled wall tube temperature, and the water dynamic cycle safety evaluation and water-cooled wall tube material safety evaluation are respectively performed according to the calculation results; the aerodynamic parameters, temperature field parameters and flue gas concentration parameters in the boiler are obtained by simulating the operation of the boiler; the dynamic field changes in the boiler are evaluated according to the simulation results; a comprehensive test is performed on the coal mill in the pulverizing system to obtain the outlet-related parameters of the coal mill under different output conditions, and the characteristics of the coal mill in the pulverizing system are evaluated based on the outlet-related parameters to obtain an overall evaluation result. The present application can solve the technical problem that the existing technology lacks reliability and comprehensiveness in boiler performance evaluation, resulting in limited practical application and poor results.

Description

Technical Field

[0001] The present application relates to the technical field of coal-fired boiler analysis, and in particular to a method and device for comprehensive evaluation of boiler performance. Background Art

[0002] In recent years, the development of renewable energy has accelerated, while the development of thermal power has slowed down. However, new energy has the characteristics of randomness, intermittency, and instability. When its proportion increases to a certain extent, it will inevitably bring greater peak-shaving pressure to the power grid. Existing coal-fired power units need to fully tap the system's peak-shaving capacity and focus on enhancing the system's flexibility and adaptability. This is an inevitable development trend of thermal power now and in the future. Among them, deep peak-shaving capacity and low-load operation adaptability are important factors that restrict the improvement of thermal power unit flexibility. Deep peak-shaving requires the unit load rate to be as low as 20% to 40%.

[0003] Since supercritical units are often designed with only a minimum of 40% to 50% rated load in mind for normal operation, various safety issues may arise at ultra-low loads that deviate from the design conditions. Existing studies have mostly focused on the performance testing or evaluation of vertical tube coil water-cooled wall boilers, and there are very few studies on ultra-low loads below 30%. In addition, current testing or evaluation technologies either lack a complete theoretical basis or do not consider the overall safety of the boiler. Therefore, the application of these theoretical methods to actual operating conditions is still limited and the results are poor. Summary of the invention

[0004] The present application provides a method and device for comprehensive evaluation of boiler performance, which is used to solve the technical problem that the existing technology lacks reliability and comprehensiveness in boiler performance evaluation, resulting in limited practical application and poor effect.

[0005] In view of this, the first aspect of the present application provides a method for comprehensive evaluation of boiler performance, comprising:

[0006] Before deep peak regulation, the water-cooled wall tube flow and water-cooled wall tube temperature are obtained by iterative calculation by dividing the water-cooled wall tube into micro-element tube segments.

[0007] According to the water-cooled wall tube flow rate, preset flow resistance and water-cooled wall tube temperature, a hydrodynamic cycle safety assessment and a water-cooled wall tube material safety assessment are performed on the boiler to obtain a first assessment result;

[0008] By simulating the operation of the boiler, the aerodynamic parameters, temperature field parameters and flue gas concentration parameters in the boiler are obtained;

[0009] Evaluate the dynamic field change in the boiler according to the aerodynamic parameters, the temperature field parameters and the flue gas concentration parameters to obtain a second evaluation result;

[0010] Conduct comprehensive tests on the coal mill in the pulverizing system to obtain the outlet-related parameters of the coal mill under different output conditions, including outlet pulverized coal parameters, output heating parameters and pulverized coal concentration in the pulverized coal tube;

[0011] A characteristic evaluation of the coal mill in the pulverizing system is performed based on the outlet-related parameters to obtain a third evaluation result.

[0012] Preferably, before the deep peak regulation, the water-cooled wall tube is divided into micro-element tube segments for iterative calculation to obtain the water-cooled wall tube flow and water-cooled wall tube temperature, including:

[0013] The parallel tube group of the platen superheater is highly discretely divided along the longitudinal extension direction to obtain a plurality of micro-element tube segments;

[0014] Based on the iterative calculation principle, the current working fluid parameter is used as the initial value of the next inlet of the micro-element pipe segment, and the next working fluid parameter of the next outlet of the micro-element pipe segment is calculated, and the current working fluid parameter is the working fluid parameter of the current outlet of the micro-element pipe segment;

[0015] According to the working fluid parameters at the inlet and outlet of each micro-element pipe segment, the wall temperature at different positions of the corresponding micro-element pipe segment is calculated to obtain the water-cooled wall pipe temperature;

[0016] The water-cooled wall tube flow rate of the corresponding water-cooled wall tube is calculated according to the working medium parameters at the outlet of each micro-element tube segment.

[0017] Preferably, the coal mill in the pulverizing system is subjected to a comprehensive test to obtain outlet-related parameters of the coal mill under different output conditions, wherein the outlet-related parameters include outlet pulverized coal parameters, output heating parameters and pulverized coal concentration in the pulverized coal tube, including:

[0018] Conduct a leveling test on the coal mill in the pulverizing system, obtain the coal powder concentration in each pulverizing tube in cold and hot states, and obtain the pulverized coal concentration in the pulverizing tube;

[0019] An output characteristic test is performed on the coal mill in the pulverizing system to obtain the outlet pulverized coal parameters and output heating parameters of the coal mill under different output conditions. The output characteristic test includes a uniform output test and a maximum output test.

[0020] Preferably, the performing characteristic evaluation on the coal mill in the pulverizing system based on the outlet-related parameters to obtain a third evaluation result includes:

[0021] Calculating a powder pipe deviation according to the powder pipe coal powder concentration; if the powder pipe deviation is less than a first powder pipe threshold, the coal mill powder pipe is in a normal state; if the powder pipe deviation exceeds a second powder pipe threshold, the coal mill powder pipe is in an abnormal state, and a leveling operation is triggered at the same time;

[0022] The output characteristics of the coal mill are evaluated and analyzed based on the outlet pulverized coal parameters and the output heating parameters to obtain an output analysis result, and the third evaluation result includes the output analysis result.

[0023] Preferably, the method further comprises: performing a characteristic evaluation on the coal mill in the pulverizing system based on the outlet-related parameters to obtain a third evaluation result, and then:

[0024] Carry out specific load efficiency test and out-of-stock performance test on boiler units respectively to obtain performance test parameters;

[0025] An overall performance evaluation of the boiler is performed according to the performance test parameters, the fourth evaluation result.

[0026] The second aspect of the present application provides a boiler performance comprehensive evaluation device, comprising:

[0027] An iterative calculation unit is used for iterative calculation before deep peak regulation by dividing the water-cooled wall tube into micro-element tube segments to obtain the water-cooled wall tube flow rate and water-cooled wall tube temperature;

[0028] A first evaluation unit is used to perform a hydrodynamic cycle safety evaluation and a water-cooled wall tube material safety evaluation on the boiler according to the water-cooled wall tube flow rate, the preset flow resistance and the water-cooled wall tube temperature, and obtain a first evaluation result;

[0029] A parameter acquisition unit, used to acquire aerodynamic parameters, temperature field parameters and flue gas concentration parameters in the boiler by simulating the operation of the boiler;

[0030] A second evaluation unit is used to evaluate the change of the power field in the boiler according to the aerodynamic parameters, the temperature field parameters and the flue gas concentration parameters to obtain a second evaluation result;

[0031] A comprehensive test unit is used to conduct a comprehensive test on the coal mill in the pulverizing system to obtain the outlet-related parameters of the coal mill under different output conditions, wherein the outlet-related parameters include outlet pulverized coal parameters, output heating parameters and pulverized coal concentration in the pulverizing tube;

[0032] The third evaluation unit is used to perform a characteristic evaluation on the coal mill in the pulverizing system based on the outlet-related parameters to obtain a third evaluation result.

[0033] Preferably, the iterative calculation unit is specifically used for:

[0034] The parallel tube group of the platen superheater is highly discretely divided along the longitudinal extension direction to obtain a plurality of micro-element tube segments;

[0035] Based on the iterative calculation principle, the current working fluid parameter is used as the initial value of the next inlet of the micro-element pipe segment, and the next working fluid parameter of the next outlet of the micro-element pipe segment is calculated, and the current working fluid parameter is the working fluid parameter of the current outlet of the micro-element pipe segment;

[0036] According to the working fluid parameters at the inlet and outlet of each micro-element pipe segment, the wall temperature at different positions of the corresponding micro-element pipe segment is calculated to obtain the water-cooled wall pipe temperature;

[0037] The water-cooled wall tube flow rate of the corresponding water-cooled wall tube is calculated according to the working medium parameters at the outlet of each micro-element tube segment.

[0038] Preferably, the comprehensive test unit is specifically used for:

[0039] Conduct a leveling test on the coal mill in the pulverizing system, obtain the coal powder concentration in each pulverizing tube in cold and hot states, and obtain the pulverized coal concentration in the pulverizing tube;

[0040] An output characteristic test is performed on the coal mill in the pulverizing system to obtain the outlet pulverized coal parameters and output heating parameters of the coal mill under different output conditions. The output characteristic test includes a uniform output test and a maximum output test.

[0041] Preferably, the third evaluation unit is specifically used for:

[0042] Calculating a powder pipe deviation according to the powder pipe coal powder concentration; if the powder pipe deviation is less than a first powder pipe threshold, the coal mill powder pipe is in a normal state; if the powder pipe deviation exceeds a second powder pipe threshold, the coal mill powder pipe is in an abnormal state, and a leveling operation is triggered at the same time;

[0043] The output characteristics of the coal mill are evaluated and analyzed based on the outlet pulverized coal parameters and the output heating parameters to obtain an output analysis result, and the third evaluation result includes the output analysis result.

[0044] Preferably, it also includes:

[0045] The efficiency test unit is used to perform specific load efficiency test and out-of-stock performance test on the boiler unit to obtain performance test parameters;

[0046] The fourth evaluation unit is used to perform an overall performance evaluation on the boiler according to the performance test parameters, and the fourth evaluation result.

[0047] It can be seen from the above technical solutions that the embodiments of the present application have the following advantages:

[0048] In the present application, a method for comprehensive evaluation of boiler performance is provided, including: before deep peak regulation, iteratively calculating by dividing the water-cooled wall tubes into micro-element tube segments to obtain the water-cooled wall tube flow and water-cooled wall tube temperature; performing a hydrodynamic cycle safety evaluation and a water-cooled wall tube material safety evaluation on the boiler according to the water-cooled wall tube flow, preset flow resistance and water-cooled wall tube temperature to obtain a first evaluation result; obtaining aerodynamic parameters, temperature field parameters and flue gas concentration parameters in the boiler by simulating boiler operation; evaluating the dynamic field changes in the boiler based on the aerodynamic parameters, temperature field parameters and flue gas concentration parameters to obtain a second evaluation result; conducting a comprehensive test on the coal mill in the pulverizing system to obtain the outlet-related parameters of the coal mill under different output conditions, the outlet-related parameters including outlet pulverized coal parameters, output heating parameters and pulverized coal concentration in the pulverizing tube; and performing a characteristic evaluation on the coal mill in the pulverizing system based on the outlet-related parameters to obtain a third evaluation result.

[0049] The application provides a comprehensive evaluation method for boiler performance, which not only performs parameter calculation and evaluation on the wall temperature and hydrodynamic conditions of the water-cooled wall tubes, but also analyzes the comprehensive operation of the coal mill in the pulverizing system through experiments; it realizes an overall evaluation of boiler performance based on different operations, taking into account most of the safety issues existing in the actual boiler operation process, and the data calculation and experimental methods can ensure the reliability of the evaluation and provide a reference basis for practical application. Therefore, the application can solve the technical problem that the existing technology lacks reliability and comprehensiveness in boiler performance evaluation, resulting in limited practical application and poor effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] Figure 1 A schematic diagram of a flow chart of a method for comprehensive evaluation of boiler performance provided in an embodiment of the present application;

[0051] Figure 2 A schematic diagram of the structure of a boiler performance comprehensive evaluation device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0052] In order to enable those skilled in the art to better understand the solution of the present application, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0053] For easier understanding, see Figure 1 , an embodiment of a boiler performance comprehensive evaluation method provided by the present application includes:

[0054] Step 101, before deep peak regulation, iterative calculation is performed by dividing the water-cooled wall tube into micro-element tube segments to obtain the water-cooled wall tube flow rate and water-cooled wall tube temperature.

[0055] Furthermore, step 101 includes:

[0056] The parallel tube group of the platen superheater is highly discretely divided along the longitudinal extension direction to obtain a plurality of micro-element tube segments;

[0057] Based on the iterative calculation principle, the current working fluid parameter is used as the initial value of the next micro-element pipe segment inlet, and the next working fluid parameter of the next micro-element pipe segment outlet is calculated. The current working fluid parameter is the working fluid parameter of the current micro-element pipe segment outlet.

[0058] According to the working fluid parameters at the inlet and outlet of each micro-element pipe section, the wall temperature at different positions of the corresponding micro-element pipe section is calculated to obtain the water-cooled wall pipe temperature;

[0059] The water-cooled wall tube flow rate of the corresponding water-cooled wall tube is calculated according to the working fluid parameters at the outlet of each micro-element tube section.

[0060] Step 102: perform a hydrodynamic cycle safety assessment and a water-cooled wall tube material safety assessment on the boiler according to the water-cooled wall tube flow rate, preset flow resistance and water-cooled wall tube temperature to obtain a first assessment result.

[0061] It should be noted that the micro-element pipe segment division method of this embodiment is a discrete division in the height direction, and multiple grids can be obtained. The connection points between grids are nodes, and each grid is a calculation unit, that is, a micro-element pipe segment. Each micro-element pipe segment includes not only the length of the pipe segment, but also its height. When studying and analyzing subsequent working fluid parameters, it may be necessary to analyze the uneven coefficient of each grid at its corresponding height. It can be understood that the length of each micro-element pipe segment can be set according to actual conditions and is not limited here. In addition, in this embodiment, only the uneven coefficient of the micro-element pipe segment at different heights is considered, so only the height is discretized, and the uneven coefficient in the width direction is not considered, that is, no additional grid division is performed in the horizontal width direction. If necessary, the grid division in the width can also be increased. The details are not repeated here.

[0062] It can be understood that iterative calculation refers to the iteration between one micro-element pipe segment and another micro-element pipe segment, that is, the working fluid parameters calculated by the previous micro-element pipe segment will affect the working fluid parameter calculation of the outlet of the next micro-element pipe segment, and the iteration is completed until all micro-element pipe segments are calculated and analyzed. Based on the calculated working fluid parameters, the water-cooled wall tube temperature and water-cooled wall tube flow can be calculated respectively; the working fluid parameters mainly include parameters such as working fluid flow, working fluid temperature and enthalpy value; so based on the working fluid flow and the calculated water-cooled wall tube flow, the wall temperature can be calculated based on the working fluid temperature to obtain the water-cooled wall tube temperature.

[0063] The water-cooled wall tube temperature and water-cooled wall tube flow in this embodiment are both calculated before the deep peak regulation of the power plant coal-fired boiler, which is essentially a boiler hydrodynamic calculation process and a boiler wall temperature calculation process. The boiler hydrodynamic calculation process can be used to analyze the boiler hydrodynamic characteristics and flow resistance characteristics. The flow resistance characteristics are analyzed by the preset flow resistance obtained by calculation to evaluate the characteristics of the boiler water circulation. The normal hydrodynamic characteristics should ensure the flow stability of the medium flowing in the heated tube, and can cool the furnace tube well to ensure the safety of the heated surface tube wall.

[0064] Before carrying out deep peak regulation of coal-fired boilers in power plants, boiler wall temperature calculation and analysis should be carried out. The safety of the pipes can be judged by calculating the wall temperature of the boiler superheater and reheater furnace. The operating conditions on the flue gas side and the steam side of the pipe have changed, which will affect the wall temperature, so the wall temperature needs to be re-evaluated to ensure that the pipe is within the allowable strength range. If the allowable strength is exceeded, the pipe should be upgraded or modified in other aspects. The boiler wall temperature calculation process can also be divided into thermal calculation, flow deviation calculation, heat absorption deviation calculation, thermal deviation calculation, and wall temperature calculation; based on these calculation results, the pipe safety assessment can also be completed. The specific calculation can be based on existing technology, which will not be repeated here.

[0065] Step 103: Acquire the aerodynamic parameters, temperature field parameters and flue gas concentration parameters in the boiler by simulating the operation of the boiler.

[0066] Step 104: Evaluate the change of the dynamic field in the boiler according to the aerodynamic parameters, the temperature field parameters and the flue gas concentration parameters to obtain a second evaluation result.

[0067] Before deep peak regulation of coal-fired boilers in power plants, relevant data of the boilers can be obtained through simulation, such as the values ​​of the aerodynamic field, temperature field, and flue gas pollutant concentration field in the boilers under deep peak regulation. The parameters obtained by simulation may include but are not limited to the above parameters. The parameters obtained by simulation can be used to analyze and evaluate the flow law, combustion law, and pollutant generation law in the boiler furnace, and then judge whether the power plant in the boiler furnace is reasonable under low load, that is, whether there is a situation where the flame scours the water-cooled wall. If not, it is normal; it can also analyze how the boiler cuts the circle, whether there are problems such as flame deflection, and if not, the boiler is normal.

[0068] Step 105, conduct a comprehensive test on the coal mill in the pulverizing system to obtain outlet-related parameters of the coal mill under different output conditions, wherein the outlet-related parameters include outlet pulverized coal parameters, output heating parameters and pulverized coal concentration in the pulverized coal tube.

[0069] Further, step 105 includes:

[0070] Conduct a leveling test on the coal mill in the pulverizing system, obtain the coal powder concentration in each pulverizing tube in cold and hot states, and obtain the pulverized coal concentration in the pulverizing tube;

[0071] The output characteristic test is carried out on the coal mill in the pulverizing system to obtain the outlet coal powder parameters and output heating parameters of the coal mill under different output conditions. The output characteristic test includes a uniform output test and a maximum output test.

[0072] It should be noted that the comprehensive test of the coal mill mainly includes a leveling test and an output characteristic test, and the leveling test includes a cold leveling test and a hot leveling test. When the boiler is deeply peaked, a leveling test should be carried out to obtain the coal powder concentration in each powder tube in the cold and hot states, and obtain the powder tube coal powder concentration.

[0073] The pulverizing system test is carried out under the unit's 30% load condition, and each test condition lasts about 3 hours. During the test, in accordance with the relevant requirements of GB10184 performance test, the boiler does not blow soot or discharge sewage, and maintains stable working conditions; during the test, AGC and primary frequency regulation are exited.

[0074] By conducting a uniform output test on the coal mill of the pulverizing system, the powder pipe at the outlet of the coal mill can be sampled and weighed under different output conditions to obtain the corresponding coal powder concentration in the powder pipe. While constantly changing the output of the coal mill, the outlet coal powder parameters can be measured, including: outlet coal powder fineness and coal powder uniformity index; the power consumption of the coal mill, the ventilation resistance of the coal mill, and the inlet and outlet temperatures can also be measured.

[0075] Conduct a maximum output test on the coal mill of the pulverizing system. First, increase the amount of coal and ventilation volume for the coal mill. Then, when it is close to the maximum output of the coal mill, increase the output of the coal mill by about 2t / h each time. Stabilize for 15 minutes. After confirming that the coal mill is working normally, continue to increase the output until the output of the coal mill is increased to the maximum output. After running stably for 1-2 hours, start measuring and recording relevant data. The relevant data include but are not limited to output heating parameters, such as the calorific value of stone coal; it can also be raw coal and coal powder sample data, coal mill output, coal mill power, coal mill dial data, etc. The specific data are not limited here.

[0076] Step 106: Evaluate the characteristics of the coal mill in the pulverizing system based on the outlet-related parameters to obtain a third evaluation result.

[0077] Further, step 106 includes:

[0078] The powder pipe deviation is calculated according to the powder pipe coal powder concentration. If the powder pipe deviation is less than the first powder pipe threshold, the coal mill powder pipe is in a normal state. If the powder pipe deviation exceeds the second powder pipe threshold, the coal mill powder pipe is in an abnormal state and the leveling operation is triggered at the same time.

[0079] The output characteristics of the coal mill are evaluated and analyzed based on the outlet coal powder parameters and the output heating parameters to obtain the output analysis results. The third evaluation results include the output analysis results.

[0080] It should be noted that the first powder hose threshold and the second powder hose threshold can be set according to actual conditions, and are not limited here. In this embodiment, after the powder hose deviation is calculated according to the powder hose coal powder concentration, during the cold state leveling test, if the powder hose deviation is less than 5%, it is a normal situation. If the powder hose deviation is greater than 5%, cold leveling is required; during the hot state leveling test, if the powder hose deviation is less than 10%, it is a normal situation. If the powder hose deviation is greater than 10%, hot leveling is required. It can be seen that different first powder hose thresholds and second powder hose thresholds can be set in both cold and hot leveling conditions.

[0081] The relevant parameters obtained from the uniform output test can reflect the output characteristics of the pulverizer under different outputs, so threshold analysis can be performed based on these obtained export coal powder parameters, such as the analysis of coal powder fineness and coal powder uniformity index. Under normal circumstances, when the export coal powder fineness is less than 20% and the coal powder uniformity index is greater than 1.1, the pulverizer output is judged to be normal; other parameters can also be judged and analyzed in this way, and the details will not be repeated here.

[0082] In the process of testing the maximum output of the coal mill in this embodiment, the calorific value of the pebble coal, which is the output heating parameter, will be measured. If the parameter exceeds 6.27MJ / KG, the coal mill is judged to be in an abnormal operating state. In addition, a similar judgment can be made by obtaining the pebble coal emission, that is, if the pebble coal emission is greater than 0.05% of the rated output of the coal mill, the coal mill is judged to be in an abnormal operating state. The above are indicators that can directly judge the abnormality of the coal mill. In actual situations, if a maximum output test is carried out, the coal powder fineness and vibration of the coal mill need to be within the normal range. Otherwise, the coal mill can also be judged to be in an abnormal operating state. The details will not be repeated here. Whether it is the evaluation result obtained from the uniform output test or the evaluation result obtained from the maximum output test, they are both the output characteristic analysis results of the coal mill, that is, the output analysis results.

[0083] Furthermore, step 106 further includes:

[0084] Carry out specific load efficiency test and out-of-stock performance test on boiler units respectively to obtain performance test parameters;

[0085] Conduct an overall performance evaluation of the boiler based on the performance test parameters, and obtain the evaluation results.

[0086] The specific load efficiency test in this embodiment refers to the efficiency test of the boiler under the condition of 30% load, the measurement time is 3 hours, the standard requirements are given, that is, the boiler does not blow soot, does not discharge sewage, maintains stable working conditions, and launches AGC and one-time leveling during the test. The efficiency test parameters of the boiler are measured, and the operating state of the boiler is evaluated as a whole based on the measured efficiency test parameters to obtain the boiler operating state evaluation result.

[0087] The out-of-stock performance test is also carried out under 30% load conditions of the unit, and the time is also 3 hours. The benchmark conditions are similar to the specific load efficiency test. Based on the test, the out-of-stock performance parameters can be measured, and the out-of-stock performance can be analyzed based on the out-of-stock performance parameters to obtain the out-of-stock performance evaluation results.

[0088] It should be noted that for the overall measurement and evaluation of boiler system performance, the furnace outlet flame temperature can also be measured by an infrared temperature measuring instrument to evaluate the change pattern of the furnace outlet flame temperature at 30% load of the unit.

[0089] In addition, it should be emphasized that since this embodiment is for the evaluation of boiler performance under deep peak load regulation, it is necessary to ensure that the boiler is under test or certain operating conditions before conducting the evaluation of this embodiment, such as all electrical, thermal interlocks and protections are normally put into operation; ensure that the test coal is sufficient, the pulverizing system is blended according to the peak load regulation plan, the coal quality can remain stable during the test, and the test load has been applied; after each change in the working condition, the working condition needs to be stabilized for at least 15-20 minutes, and the oxygen content, temperature, pressure, flow, differential pressure, smoke pressure and other meters on the wind and smoke system should all display accurately. In addition, before the test, it is necessary to confirm that the coal entering the furnace is close to the commonly used domestic bituminous coal and high-volatile Indonesian coal, and the fineness of the coal powder is within the design range; confirm that the furnace pressure fluctuation is within the normal range, the combustion is normal, and the fire detection signal is normal; confirm that the fuel system is normal, there is circulation to the front of the furnace, and the manual door of the oil gun is open, so that it can be put into use at any time when the combustion is unstable. In addition, it is also necessary to confirm that the boiler air volume is not less than 25%-30%, the boiler main fuel tripping action, and exit through the 3-out-2 logic protection; ensure that the micro-oil gun and the corresponding ignition gun of the running coal mill are reliable and standby, and test the micro-oil gun before deep peak regulation every day and the corresponding ignition gun of the running coal mill during planned peak regulation; ensure that the wind pressure, wind speed, and temperature measurement points of the pulverizing system are reliable to ensure the safe standby and stable adjustment of the pulverizing system; test the electric water supply pump before peak regulation operation to put it in a reliable standby state.

[0090] The embodiment of the present application provides a method for comprehensive evaluation of boiler performance, which not only performs parameter calculation and evaluation on the wall temperature and hydrodynamic conditions of the water-cooled wall tubes, but also analyzes the comprehensive operation of the coal mill in the pulverizing system by means of experiments; it realizes an overall evaluation of boiler performance based on different operations, taking into account most of the safety issues existing in the actual boiler operation process, and the data calculation and experimental methods can ensure the reliability of the evaluation, and can provide a reference basis for practical application. Therefore, the embodiment of the present application can solve the technical problem that the existing technology lacks reliability and comprehensiveness in boiler performance evaluation, resulting in limited practical application and poor effect.

[0091] For easier understanding, see Figure 2 The present application provides an embodiment of a boiler performance comprehensive evaluation device, comprising:

[0092] An iterative calculation unit 201 is used for performing iterative calculation before deep peak regulation by dividing the water-cooled wall tube into micro-element tube segments to obtain the water-cooled wall tube flow rate and water-cooled wall tube temperature;

[0093] The first evaluation unit 202 is used to perform a hydrodynamic cycle safety evaluation and a water wall tube material safety evaluation on the boiler according to the water wall tube flow rate, the preset flow resistance and the water wall tube temperature, and obtain a first evaluation result;

[0094] The parameter acquisition unit 203 is used to acquire the aerodynamic parameters, temperature field parameters and flue gas concentration parameters in the boiler by simulating the operation of the boiler;

[0095] The second evaluation unit 204 is used to evaluate the dynamic field change in the boiler according to the aerodynamic parameters, the temperature field parameters and the flue gas concentration parameters to obtain a second evaluation result;

[0096] The comprehensive test unit 205 is used to conduct a comprehensive test on the coal mill in the pulverizing system to obtain the outlet-related parameters of the coal mill under different output conditions, wherein the outlet-related parameters include the outlet pulverized coal parameters, the output heating parameters and the pulverized coal concentration in the pulverized coal tube;

[0097] The third evaluation unit 206 is used to evaluate the characteristics of the coal mill in the pulverizing system based on the outlet related parameters to obtain a third evaluation result.

[0098] Further, the iterative calculation unit 201 is specifically used for:

[0099] The parallel tube group of the platen superheater is highly discretely divided along the longitudinal extension direction to obtain a plurality of micro-element tube segments;

[0100] Based on the iterative calculation principle, the current working fluid parameter is used as the initial value of the next micro-element pipe segment inlet, and the next working fluid parameter of the next micro-element pipe segment outlet is calculated. The current working fluid parameter is the working fluid parameter of the current micro-element pipe segment outlet.

[0101] According to the working fluid parameters at the inlet and outlet of each micro-element pipe section, the wall temperature at different positions of the corresponding micro-element pipe section is calculated to obtain the water-cooled wall pipe temperature;

[0102] The water-cooled wall tube flow rate of the corresponding water-cooled wall tube is calculated according to the working fluid parameters at the outlet of each micro-element tube section.

[0103] Furthermore, the comprehensive test unit 205 is specifically used for:

[0104] Conduct a leveling test on the coal mill in the pulverizing system, obtain the coal powder concentration in each pulverizing tube in cold and hot states, and obtain the pulverized coal concentration in the pulverizing tube;

[0105] The output characteristic test is carried out on the coal mill in the pulverizing system to obtain the outlet coal powder parameters and output heating parameters of the coal mill under different output conditions. The output characteristic test includes a uniform output test and a maximum output test.

[0106] Further, the third evaluation unit 206 is specifically configured to:

[0107] The powder pipe deviation is calculated according to the powder pipe coal powder concentration. If the powder pipe deviation is less than the first powder pipe threshold, the coal mill powder pipe is in a normal state. If the powder pipe deviation exceeds the second powder pipe threshold, the coal mill powder pipe is in an abnormal state and the leveling operation is triggered at the same time.

[0108] The output characteristics of the coal mill are evaluated and analyzed based on the outlet coal powder parameters and the output heating parameters to obtain the output analysis results. The third evaluation results include the output analysis results.

[0109] Furthermore, it also includes:

[0110] The efficiency test unit 207 is used to perform a specific load efficiency test and an out-of-stock performance test on the boiler unit to obtain performance test parameters;

[0111] The fourth evaluation unit 208 is used to perform an overall performance evaluation on the boiler according to the performance test parameters, and obtain a fourth evaluation result.

[0112] In the several embodiments provided in the present application, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0113] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0114] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0115] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application is essentially or the part that contributes to the prior art or all or part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a number of instructions for executing all or part of the steps of the method described in each embodiment of the present application through a computer device (which can be a personal computer, a server, or a network device, etc.). The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (full name in English: Read-Only Memory, English abbreviation: ROM), random access memory (full name in English: Random Access Memory, English abbreviation: RAM), disk or optical disk and other media that can store program codes.

[0116] As described above, the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A method for comprehensive evaluation of boiler performance, characterized in that: include: Before deep peak regulation, the water-cooled wall tubes are divided into micro-element tube segments for iterative calculation to obtain the water-cooled wall tube flow and water-cooled wall tube temperature. The iterative calculation process is: The parallel tube group of the platen superheater is highly discretely divided along the longitudinal extension direction to obtain a plurality of micro-element tube segments; Based on the iterative calculation principle, the current working fluid parameter is used as the initial value of the next inlet of the micro-element pipe segment, and the next working fluid parameter of the next outlet of the micro-element pipe segment is calculated, and the current working fluid parameter is the working fluid parameter of the current outlet of the micro-element pipe segment; According to the working fluid parameters at the inlet and outlet of each micro-element pipe segment, the wall temperature at different positions of the corresponding micro-element pipe segment is calculated to obtain the water-cooled wall pipe temperature; Calculate the water-cooled wall tube flow rate of the corresponding water-cooled wall tube according to the working fluid parameters at the outlet of each micro-element tube segment; According to the water-cooled wall tube flow rate, the preset flow resistance and the water-cooled wall tube temperature, a hydrodynamic cycle safety assessment and a water-cooled wall tube material safety assessment are performed on the boiler to obtain a first assessment result; By simulating the operation of the boiler, the aerodynamic parameters, temperature field parameters and flue gas concentration parameters in the boiler are obtained; Evaluate the dynamic field change in the boiler according to the aerodynamic parameters, the temperature field parameters and the flue gas concentration parameters to obtain a second evaluation result; Conduct comprehensive tests on the coal mill in the pulverizing system to obtain the outlet-related parameters of the coal mill under different output conditions, including outlet pulverized coal parameters, output heating parameters and pulverized coal concentration in the pulverized coal tube; The coal mill in the pulverizing system is characterized by evaluating the characteristics based on the outlet-related parameters to obtain a third evaluation result. The evaluation process is as follows: Calculating a powder pipe deviation according to the powder pipe coal powder concentration; if the powder pipe deviation is less than a first powder pipe threshold, the coal mill powder pipe is in a normal state; if the powder pipe deviation exceeds a second powder pipe threshold, the coal mill powder pipe is in an abnormal state, and a leveling operation is triggered at the same time; The output characteristics of the coal mill are evaluated and analyzed based on the outlet pulverized coal parameters and the output heating parameters to obtain an output analysis result, and the third evaluation result includes the output analysis result.

2. The boiler performance comprehensive evaluation method according to claim 1, characterized in that: The comprehensive test is conducted on the coal mill in the pulverizing system to obtain the outlet-related parameters of the coal mill under different output conditions, wherein the outlet-related parameters include the outlet pulverized coal parameters, the output heating parameters and the pulverized coal concentration in the pulverized coal tube, including: Conduct a leveling test on the coal mill in the pulverizing system, obtain the coal powder concentration in each pulverizing tube in cold and hot states, and obtain the pulverized coal concentration in the pulverizing tube; An output characteristic test is performed on the coal mill in the pulverizing system to obtain the outlet pulverized coal parameters and output heating parameters of the coal mill under different output conditions. The output characteristic test includes a uniform output test and a maximum output test.

3. The boiler performance comprehensive evaluation method according to claim 1, characterized in that: The method further comprises: performing a characteristic evaluation on the coal mill in the pulverizing system based on the outlet-related parameters to obtain a third evaluation result; and then: Carry out specific load efficiency test and out-of-stock performance test on boiler units respectively to obtain performance test parameters; An overall performance evaluation of the boiler is performed according to the performance test parameters, the fourth evaluation result.

4. A boiler performance comprehensive evaluation device, characterized in that: include: The iterative calculation unit is used to perform iterative calculations before deep peak regulation by dividing the water-cooled wall tubes into micro-element tube segments to obtain the water-cooled wall tube flow and water-cooled wall tube temperature. The iterative calculation unit is specifically used to: The parallel tube group of the platen superheater is highly discretely divided along the longitudinal extension direction to obtain a plurality of micro-element tube segments; Based on the iterative calculation principle, the current working fluid parameter is used as the initial value of the next inlet of the micro-element pipe segment, and the next working fluid parameter of the next outlet of the micro-element pipe segment is calculated, and the current working fluid parameter is the working fluid parameter of the current outlet of the micro-element pipe segment; According to the working fluid parameters at the inlet and outlet of each micro-element pipe segment, the wall temperature at different positions of the corresponding micro-element pipe segment is calculated to obtain the water-cooled wall pipe temperature; Calculate the water-cooled wall tube flow rate of the corresponding water-cooled wall tube according to the working fluid parameters at the outlet of each micro-element tube segment; A first evaluation unit is used to perform a hydrodynamic cycle safety evaluation and a water-cooled wall tube material safety evaluation on the boiler according to the water-cooled wall tube flow rate, the preset flow resistance and the water-cooled wall tube temperature, and obtain a first evaluation result; A parameter acquisition unit, used to acquire aerodynamic parameters, temperature field parameters and flue gas concentration parameters in the boiler by simulating the operation of the boiler; A second evaluation unit is used to evaluate the change of the power field in the boiler according to the aerodynamic parameters, the temperature field parameters and the flue gas concentration parameters to obtain a second evaluation result; A comprehensive test unit is used to conduct a comprehensive test on the coal mill in the pulverizing system to obtain the outlet-related parameters of the coal mill under different output conditions, wherein the outlet-related parameters include the outlet pulverized coal parameters, output heating parameters and pulverized coal concentration in the pulverized coal tube; The third evaluation unit is used to evaluate the characteristics of the coal mill in the pulverizing system based on the outlet-related parameters to obtain a third evaluation result. The third evaluation unit is specifically used to: Calculating a powder pipe deviation according to the powder pipe coal powder concentration; if the powder pipe deviation is less than a first powder pipe threshold, the coal mill powder pipe is in a normal state; if the powder pipe deviation exceeds a second powder pipe threshold, the coal mill powder pipe is in an abnormal state, and a leveling operation is triggered at the same time; The output characteristics of the coal mill are evaluated and analyzed based on the outlet pulverized coal parameters and the output heating parameters to obtain an output analysis result, and the third evaluation result includes the output analysis result.

5. The boiler performance comprehensive evaluation device according to claim 4, characterized in that: The comprehensive test unit is specifically used for: Conduct a leveling test on the coal mill in the pulverizing system, obtain the coal powder concentration in each pulverizing tube in cold and hot states, and obtain the pulverized coal concentration in the pulverizing tube; An output characteristic test is performed on the coal mill in the pulverizing system to obtain the outlet pulverized coal parameters and output heating parameters of the coal mill under different output conditions. The output characteristic test includes a uniform output test and a maximum output test.

6. The boiler performance comprehensive evaluation device according to claim 4, characterized in that: Also includes: The efficiency test unit is used to perform specific load efficiency test and out-of-stock performance test on the boiler unit to obtain performance test parameters; The fourth evaluation unit is used to perform an overall performance evaluation on the boiler according to the performance test parameters, and the fourth evaluation result.

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