A method and system for flue gas pollutant abatement in a gas turbine combustor

Abstract

The application discloses a method and system for reducing flue gas pollutant emission of a gas turbine combustion chamber, and the method comprises the following steps: performing correlation analysis on flue gas pollutant emission characteristics of the gas turbine combustion chamber corresponding to different starting conditions and different load conditions, and determining a factor that most influences flue gas pollutant emission; and performing optimization on a running process of the gas turbine combustion chamber according to the factor that most influences flue gas pollutant emission, so as to reduce flue gas pollutant emission. The method gives specific technical measures and operation optimization suggestions for optimizing the combustion operation of the gas turbine, and the method can also play a good guiding role for pollutant emission reduction of the same type of unit and design of a new unit.

Description

Technical Field

[0001] This invention relates to the field of pollutant emission reduction, specifically to a method and system for reducing pollutant emissions from flue gas in a gas turbine combustion chamber. Background Technology

[0002] With increasing pressure on environmental protection, more stringent requirements have been placed on pollutant emissions from thermal power plants. Although natural gas has lower pollutant emissions from fossil fuel power generation, gas turbine power generation companies still need to actively seek further technical measures that may reduce gas turbine pollutant emissions.

[0003] To reduce emissions of pollutants from the combustion chamber of a gas turbine, the common methods to achieve this goal are: optimizing the combustion operation of the gas turbine, installing denitrification and desulfurization devices, or combining optimization of the combustion operation of the gas turbine with the installation of denitrification and desulfurization devices.

[0004] Although the above-mentioned methods of reducing combustion chamber flue gas pollutants by modifying the burner or adding denitrification and desulfurization devices can achieve the goal of reducing flue gas pollutants, with increasingly stringent environmental protection policies, if further reduction of pollutant emissions is required, it is also necessary to optimize the combustion operation of the gas turbine in combination with the operating data of the gas-steam combined cycle unit in order to achieve the goal of reducing flue gas pollutants from the gas turbine. Summary of the Invention

[0005] To address the problems existing in the prior art, this invention proposes a method and system for reducing flue gas pollutants in the combustion chamber of a gas turbine. This method mainly analyzes the changing patterns of gas turbine pollutant emissions, the influencing factors and patterns of major pollutant generation, and provides strategies for pollutant reduction and operation optimization.

[0006] This invention is achieved through the following technical solution:

[0007] A method for reducing pollutant emissions from the combustion chamber of a gas turbine includes the following steps:

[0008] Step 1: Based on the flue gas pollutant emission data of the gas turbine combustor under different start-up conditions, obtain the flue gas pollutant emission characteristics of the gas turbine combustor under different start-up conditions.

[0009] Step 2: Obtain flue gas pollutant emission data of the gas turbine combustor under different load conditions, and obtain the flue gas pollutant emission characteristics of the gas turbine combustor under different load conditions;

[0010] Step 3: Conduct a correlation analysis on the emission characteristics of flue gas pollutants from the gas turbine combustion chamber under different start-up states and different load conditions obtained in Step 1 and Step 2 to determine the factors that have the greatest impact on flue gas pollutant emissions.

[0011] Step 4: Optimize the operation of the gas turbine combustion chamber based on the factors that have the greatest impact on flue gas pollutant emissions to reduce flue gas pollutant emissions.

[0012] Preferably, the different start-up states include cold start-up, warm start-up, and hot start-up;

[0013] The temperature-state start-up includes cold-temperature start-up and hot-temperature start-up;

[0014] The hot start-up includes normal hot start-up and extremely hot start-up.

[0015] Preferably, the different load conditions mentioned in step 2 include the load changes of the gas-steam combined cycle unit from start-up to stable load and then to shutdown.

[0016] The stable load refers to the full-load operating condition of the gas-steam combined cycle unit.

[0017] Preferably, the emission characteristics of the flue gas pollutants in the combustion chamber are the patterns of change of flue gas pollutant parameters over time.

[0018] Preferably, in step 3, a significance test method is used to analyze the correlation of the emission characteristics of flue gas pollutants from the gas turbine combustion chamber.

[0019] Preferably, the significance test method is as follows:

[0020] The correlation coefficient between two flue gas pollutant emission characteristics is determined using the Pearson product-moment correlation coefficient method. A statistic t is constructed based on the correlation coefficient, and the significance probability p is calculated using the TDIST function. The correlation between the two flue gas pollutant emission characteristics is analyzed based on the significance probability p, and the factor with the greatest influence on flue gas pollutant emissions is determined.

[0021] Preferably, the correlation coefficient is calculated using the following method:

[0022]

[0023] In the formula, x i y i The sampled data are for the parameter variables under study. This represents the average value of the corresponding sampled data.

[0024] Preferably, the expression for the statistic t is as follows:

[0025]

[0026] In the formula, n is the number of samples and r is the correlation coefficient.

[0027] Preferably, the expression for the significance probability p is as follows:

[0028] p = TDIST(t, n-2, 2)

[0029] A system for a method of reducing flue gas pollutant emissions from a gas turbine combustion chamber includes,

[0030] The start-up state emission characteristics module is used to obtain the emission characteristics of gas turbine combustor flue gas pollutants under different start-up states based on the flue gas pollutant emission data of the gas turbine combustor under different start-up states.

[0031] The load-state emission characteristics module is used to acquire flue gas pollutant emission data of the gas turbine combustor under different load conditions, and obtain the flue gas pollutant emission characteristics of the gas turbine combustor under different load conditions;

[0032] The correlation analysis module is used to perform correlation analysis on the emission characteristics of flue gas pollutants from the gas turbine combustor under different start-up states and different load conditions, and to determine the factors that have the greatest impact on flue gas pollutant emissions.

[0033] The optimization module is used to optimize the operation of the gas turbine combustion chamber based on the factors that have the greatest impact on flue gas pollutant emissions, thereby reducing flue gas pollutant emissions.

[0034] Compared with the prior art, the present invention has the following beneficial technical effects:

[0035] This invention provides a method for reducing flue gas pollutant emissions from a gas turbine combustor. Targeting flue gas pollutants from a gas turbine combustor, the method performs correlation analysis on the emission characteristics of flue gas pollutants under different start-up states and load conditions to identify the factors that have the greatest impact on flue gas pollutant emissions. Based on these factors, the operation of the gas turbine combustor is optimized to reduce emissions. Gas turbine power plant operators can clearly understand the rationale behind the operational optimization recommendations using this method. Furthermore, this method can provide valuable guidance for pollutant reduction in similar units and for the design of new units. Attached Figure Description

[0036] Figure 1 This is a schematic diagram of the method for reducing pollutant emissions from the combustion chamber of a gas turbine according to the present invention. Detailed Implementation

[0037] The present invention will now be described in further detail with reference to the accompanying drawings. These descriptions are intended to explain the invention and not to limit it.

[0038] See Figure 1 A method for reducing pollutant emissions from the combustion chamber of a gas turbine includes the following steps:

[0039] Step 1: Determine the emission data of flue gas pollutants from the gas turbine combustion chamber, and the layout of sampling points for flue gas pollutant measurement equipment.

[0040] Specifically, the main pollutant components in the gas turbine exhaust that need to be monitored and analyzed should be identified; the measuring equipment for measuring specific pollutant components and the operating conditions under which gas turbine combustion chamber flue gas pollutant emissions need to be measured should be specified.

[0041] The flue gas pollutant sampling points of the flue gas pollutant measuring equipment are reasonably arranged, the measuring equipment must be correctly installed, and within the validity period of the inspection certificate, the flue gas pollutant measuring equipment is used to measure and collect flue gas pollutant emissions from the combustion chamber under the set gas turbine operating conditions.

[0042] Step 2: Obtain flue gas pollutant emission data of the gas turbine combustor under different start-up conditions, and obtain the flue gas pollutant emission characteristics of the gas turbine combustor under different start-up conditions;

[0043] Specifically, the different start-up processes can be divided into cold start-up, warm start-up, and hot start-up based on the length of the shutdown time, the temperature of the metal at the inlet of the high-pressure cylinder, or the temperature of the inner wall of the upper cylinder of the intermediate and high-pressure cylinders.

[0044] The term "warm start" can be further divided into "cold warm start" and "hot warm start" in a certain type of gas turbine; the term "hot start" can also be divided into "hot start" and "extremely hot start" in a certain type of gas turbine, depending on the length of the shutdown time.

[0045] Based on the flue gas pollutant emission data collected during different start-up processes of the gas turbine, the emission characteristics of flue gas pollutants in the gas turbine combustion chamber under different start-up conditions were determined; the emission characteristics of flue gas pollutants are the laws governing the changes of flue gas pollutants in the gas turbine combustion chamber and parameters closely related to flue gas pollutants over time.

[0046] Step 3: Obtain flue gas pollutant emission data of the gas turbine combustor under different load conditions, and obtain the flue gas pollutant emission characteristics of the gas turbine combustor under different load conditions.

[0047] Specifically, the different loads refer to the load changes of the gas-steam combined cycle unit from start-up to stable load and then to shutdown; the stable load refers to the operating condition of the gas-steam combined cycle unit reaching full load.

[0048] Based on the flue gas pollutant emission data collected under different load conditions of the gas turbine, the emission characteristics of flue gas pollutants in the combustion chamber are analyzed. The emission characteristics of flue gas pollutants in the combustion chamber refer to the changes in flue gas pollutants and closely related parameters over time.

[0049] Step 4: Use statistical methods to conduct correlation analysis on the emission characteristics of flue gas pollutants from the gas turbine combustion chamber under different start-up states and different load conditions obtained in Step 1 and Step 2, and determine the factors that have the greatest impact on flue gas pollutant emissions.

[0050] Specifically, the significance test method is used to analyze the correlation between the change pattern and the influencing factors. First, the correlation coefficient between the emission characteristics of two flue gas pollutants is determined according to the Pearson product-moment correlation coefficient method. The statistic t is constructed based on the correlation coefficient, and the significance probability p is calculated in combination with the TDIST function. The correlation between the emission characteristics of the two flue gas pollutants is analyzed based on the significance probability p, and the factor with the greatest influence on the emission of flue gas pollutants is determined.

[0051] The statistical method used was the Pearson product-moment correlation coefficient method, which was used to calculate the Pearson correlation coefficient between the two variables. The formula is as follows:

[0052]

[0053] In the formula, r is the Pearson correlation coefficient between the two variables, and x i y i The sampled data are for the parameter variables under study. This represents the average value of the corresponding sampled data.

[0054] Pearson correlation coefficient and significance test are usually used together to evaluate whether two variables are significantly correlated. The significance test is represented by the t-test, which yields the significance probability p-value. When calculating the significance probability p-value, a t-statistic needs to be constructed using the Pearson correlation coefficient. The formula for calculating the t-statistic is:

[0055]

[0056] In the formula, n is the sample size. The statistic t has been shown to conform to a t-distribution with n-2 degrees of freedom.

[0057] Based on the t-values ​​mentioned above, the TDIST function in Excel is used to calculate the p-value, which represents the significance of the t-test. The specific format is as follows:

[0058] p = TDIST(t, n-2, 2) (3)

[0059] In the formula, t is the statistical value calculated by formula (2), n is the sample size, n-2 is the degree of freedom, and 2 indicates that the distribution is two-sided.

[0060] Step 5: Optimize the operation of the gas turbine combustion chamber based on the factors that have the greatest impact on flue gas pollutant emissions, thereby reducing flue gas pollutant emissions.

[0061] This invention proposes a method for reducing flue gas pollutant emissions from gas turbine combustors. The method analyzes the combustion characteristics of flue gas pollutants under different start-up processes and load conditions, and studies the correlation between flue gas pollutants and influencing factors. Finally, it proposes recommendations for flue gas pollutant emission reduction. The method provided by this invention offers specific technical measures and operational optimization suggestions for gas turbine combustion operation. Gas turbine power generation company operators can clearly understand the rationale behind the operational optimization suggestions through this method. Furthermore, this method can also provide good guidance for pollutant emission reduction in similar units and the design of new units.

[0062] Example 1

[0063] The following description uses the emission reduction of flue gas pollutants in the combustion chamber of a gas turbine in a gas-steam combined cycle unit as an example, and the specific embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0064] The emission reduction process of flue gas pollutants in the gas turbine combustion chamber of this embodiment is as follows:

[0065] Step 1: Determine that the main pollutant component in the gas turbine exhaust is NO. X SO2 and particulate matter. It is necessary to measure, collect, and analyze the emissions of gas turbine combustor pollutants under different start-up processes and load conditions, and ultimately propose operation optimization methods and countermeasures.

[0066] Based on the above, it was determined that the CEMS system of the gas turbine power generation plant would be used to measure NO in the flue gas. X Emissions of SO2 and particulate matter. Gas turbine emissions are measured during different start-up phases (cold, cold-temperature, hot-temperature, hot) as well as during the stable operation and shutdown phases. Gas turbine emissions are also measured under different load conditions throughout the entire process from start-up to stable operation and shutdown.

[0067] Measuring and collecting flue gas pollutant emission data during different start-up processes requires a significant amount of time to wait for the gas turbine to reach the desired start-up state for flue gas pollutant emissions. To reduce waiting time, historical operating data from this start-up state can be analyzed.

[0068] Before measuring and collecting flue gas pollutant components, confirm that the flue gas pollutant emission measurement points of the CEMS system are located at the dedicated sampling points set up on the chimney outlet platform, and that the layout is reasonable; that the CEMS system measurement equipment is installed correctly and within the validity period of its inspection certificate.

[0069] Data on flue gas pollutants were measured and collected under the established operating conditions of the gas turbine. Each measurement included data on O2, NOx, SO2, and particulate matter during unit startup, shutdown, and stable operation.

[0070] Step 2: Analyze the flue gas pollutant emissions and historical operating data of the unit during the cold, cold-temperature, hot-temperature, and hot start-up processes. It can be seen that the corresponding flue gas pollutants (NOx, SO2, and particulate matter) change over time in the same start-up process are basically the same. Therefore, the emission and operating data of the cold, cold-temperature, hot-temperature, and hot start-up processes are selected respectively to compare and analyze the changes of flue gas pollutants and closely related parameters of flue gas pollutants over time in different start-up processes.

[0071] Analysis of the time-varying patterns of flue gas pollutants (NOx, SO2, and particulate matter) reveals that during different start-up processes, NOx emission concentrations initially increase gradually, reach a peak, and then gradually decrease. Once the load stabilizes, NOx emission concentrations show minimal change, remaining essentially at the same level. SO2 emission concentrations consistently increase first and then decrease; when the gas turbine load reaches approximately 100MW, the SO2 emission concentration is almost 0 mg / Nm³. 3 The emission concentrations of particulate matter initially increase and then decrease. During cold start-up, the highest concentrations of NOx, SO2, and particulate matter last the longest. During hot start-up, the highest concentrations of NOx, SO2, and particulate matter last the shortest.

[0072] Analyzing the time-varying curves of parameters such as gas turbine load, fuel quantity, IGV valve position, and combustion chamber bypass valve opening reveals that the main fuel quantity and gas turbine load exhibit essentially the same time-varying patterns. During the initial startup phase, from ignition and acceleration to before grid connection, the standby fuel quantity is the highest, while the main fuel quantity is relatively low. The combustion chamber bypass valve is fully open to ensure a high air-fuel ratio and stable combustion within the combustion chamber. The IGV valve position is approximately 40%, at which point the combustion chamber outlet temperature rises rapidly.

[0073] Based on the NOx emission data during different start-up processes and the time-varying patterns of key parameters, it can be seen that the highest NOx concentrations consistently occur before the start of warm-up load after grid connection. Between warm-up load and 200MW, the NOx emission concentration shows a generally consistent downward trend with respect to the shift fuel quantity and combustion chamber bypass valve opening. Between 200MW and full load, the NOx emission pattern is consistent with the time-varying patterns of shift fuel quantity, main fuel quantity, and IGV valve position, maintaining a low NOx concentration. When the combustion chamber outlet temperature is too high, the air-fuel ratio can be adjusted by increasing the IGV valve position or closing the combustion chamber bypass valve opening.

[0074] Step 3: Analyze the variation patterns of flue gas pollutants (NOx, SO2, particulate matter) over time under different loads. It can be seen that during startup, after grid connection, as the unit load increases, NOx... X The concentration initially rises, then gradually decreases, with a slow decreasing trend; after the unit load exceeds the warm-up load, NO... X The concentration initially decreased sharply, and then stabilized after the unit load stabilized. After the gas turbine was connected to the grid but before reaching the warm-up load of 120MW, the SO2 concentration gradually decreased with increasing load, eventually dropping to 0 mg / Nm³. 3 Nearby, the smoke and dust levels remain largely unchanged regardless of the load.

[0075] During the shutdown process, before the gas turbine load drops to 100MW, the NO in the flue gas X The concentration remained basically unchanged; after the gas turbine load dropped to 100MW, NO concentration... X The concentration gradually increased as the gas turbine load decreased, reaching a peak at 20MW; when the gas turbine load decreased to 100MW, the SO2 concentration was almost 0mg / Nm³. 3 As the gas turbine load continues to decrease, the SO2 concentration gradually increases; the amount of particulate matter emissions remains basically unchanged with the load.

[0076] Analyzing the variation curves of parameters such as unit load, gas turbine load, fuel quantity, IGV valve position, combustion chamber bypass valve opening, combustion chamber outlet temperature, and combustion chamber pressure under different load conditions, it was found that during the process of gradually increasing the gas turbine load from 20MW but not reaching the warm-up load of 120MW, the proportion of fuel in the combustion chamber gradually decreased, indicating that the main fuel quantity was gradually increasing. This further suggests that some of the fuel entering the combustion chamber had been premixed with air through the fuel nozzles for premixed combustion. After the unit load exceeded the warm-up load of 120MW, the proportion of fuel in the combustion chamber continued to decrease, the opening of the combustion chamber bypass valve gradually decreased, the amount of air participating in combustion increased, and the combustion chamber fuel-air ratio continued to decrease. During the process of increasing gas turbine load, the compressor outlet temperature, fuel heater outlet temperature, and combustion chamber pressure all fluctuated, leading to fluctuations in the uniformity of air-fuel mixing in the combustion chamber. During the shutdown process, as the load decreased, the opening of the combustion chamber bypass valve gradually increased, the proportion of fuel in the combustion chamber gradually increased, and the combustion mode changed from premixed combustion to diffusion combustion.

[0077] Step 4: Correlation analysis was performed on the gas turbine load, the opening degree of the standby fuel flow control valve, the opening degree of the combustion chamber bypass valve, and the combustion chamber outlet temperature during the start-up process, and the gas turbine NOx emission concentration. The results showed that the correlation coefficients between the gas turbine NOx emission concentration and the opening degree of the standby fuel flow control valve and the opening degree of the combustion chamber bypass valve were 0.706 and 0.404, respectively. The significance probability of the t-test was 0.000 < 0.01 for both, rejecting the null hypothesis. This indicates that the gas turbine NOx emission concentration is significantly correlated with both variables, while the correlation coefficients between the gas turbine NOx emission concentration and the gas turbine load and combustion chamber outlet temperature are relatively small. During the unit start-up process, the most important factor affecting the gas turbine NOx emission concentration is the opening degree of the standby fuel flow control valve (standby fuel flow), followed by the opening degree of the combustion chamber bypass valve (amount of air entering the combustion chamber), while the influence of the gas turbine load and the combustion chamber outlet temperature is relatively weak.

[0078] Correlation analysis was conducted on the gas turbine load, the opening degree of the standby fuel flow control valve, the opening degree of the combustion chamber bypass valve, the combustion chamber outlet temperature, and the SO2 emission concentration during the start-up process. The results showed that the correlation coefficients between the gas turbine SO2 emission concentration and the gas turbine load and combustion chamber outlet temperature were -0.645 and -0.687, respectively, with a t-test significance probability of 0.000 < 0.01 for both, rejecting the null hypothesis. This indicates a strong negative correlation between SO2 emission concentration and gas turbine load and combustion chamber outlet temperature. The correlation coefficient between the standby fuel flow control valve opening and SO2 emission concentration was 0.179, with a t-test significance probability of 0.000 < 0.01, rejecting the null hypothesis. This indicates that the standby fuel flow control valve opening has a relatively small impact on SO2 emission concentration. The correlation coefficient between the combustion chamber bypass valve opening and SO2 emission concentration was 0.052, with a t-test significance probability of 0.318 > 0.01, indicating no correlation between the combustion chamber bypass valve opening and SO2 emission concentration.

[0079] The correlation between gas turbine load, the opening degree of the standby fuel flow control valve, the opening degree of the combustion chamber bypass valve, and the combustion chamber outlet temperature during shutdown and the NOx emission concentration of the gas turbine was analyzed. The results showed that the opening degree of the standby fuel flow control valve and the opening degree of the combustion chamber bypass valve were significantly positively correlated with the NOx emission concentration, with correlation coefficients of 0.468 and 0.332, respectively. The significance probability of the t-test for both was 0.000 < 0.01, rejecting the null hypothesis, indicating that the NOx emission concentration has a strong correlation with the opening degree of the standby fuel flow control valve and the opening degree of the combustion chamber bypass valve. The correlation coefficient between the NOx emission concentration and the gas turbine load was -0.377, and the significance probability of the t-test was 0.000 < 0.01, rejecting the null hypothesis, indicating that the NOx emission concentration and the gas turbine load have a negative correlation during shutdown. Based on the above analysis, the most significant factor affecting NOx emission concentration during unit shutdown is the opening degree of the standby fuel flow control valve (standby fuel flow), followed by the gas turbine load and the opening degree of the combustion chamber bypass valve (amount of air entering the combustion chamber), while the combustion chamber outlet temperature has the weakest impact.

[0080] The correlation between gas turbine load, the opening degree of the standby fuel flow control valve, the opening degree of the combustion chamber bypass valve, the combustion chamber outlet temperature, and SO2 emission concentration during the shutdown process was analyzed. The results showed that the correlation coefficients between the gas turbine SO2 emission concentration and the gas turbine load and the combustion chamber bypass valve opening degree were -0.402 and 0.443, respectively, with a significance probability of 0.000 < 0.01 for both, rejecting the null hypothesis. This indicates that SO2 emission concentration exhibits a negative correlation with the gas turbine load, but a positive correlation with the combustion chamber bypass valve opening degree. The correlation coefficient between the standby fuel flow control valve opening degree and SO2 emission concentration was 0.157, with a significance probability of 0.000 < 0.01, rejecting the null hypothesis. This indicates that the standby fuel flow control valve opening degree is related to SO2 emission concentration, but the effect is small. The correlation coefficient between the combustion chamber outlet temperature and the gas turbine SO2 emission concentration was -0.093, with a significance probability of 0.191 > 0.01, indicating that the combustion chamber outlet temperature and SO2 emission concentration are not correlated.

[0081] When the unit is running stably, the concentrations of SO2 and particulate matter are at very low levels. Therefore, the focus of the analysis during stable operation is on the relationship between the NOx emission concentration of the gas turbine and various parameters. The correlation between gas turbine load, the opening degree of the standby fuel flow control valve, the opening degree of the combustion chamber bypass valve, and the combustion chamber outlet temperature and the gas turbine NOx emission concentration during stable operation of the unit was analyzed. The results showed that the correlation coefficients between the gas turbine NOx emission concentration and the gas turbine load, the opening degree of the standby fuel flow control valve, the opening degree of the combustion chamber bypass valve, and the combustion chamber outlet temperature were 0.598, 0.649, -0.496, and 0.674, respectively. The significance probability of the t-test was 0.000 < 0.01 for all of them, rejecting the null hypothesis. This indicates that the gas turbine NOx emission concentration is positively correlated with the gas turbine load, the opening degree of the standby fuel flow control valve, and the combustion chamber outlet temperature, but negatively correlated with the opening degree of the combustion chamber bypass valve. During stable operation of the unit, the combustion chamber outlet temperature and the opening degree of the standby fuel flow control valve are two important factors affecting the gas turbine NOx emission concentration. At the same time, the gas turbine load and the opening degree of the combustion chamber bypass valve also affect the gas turbine NOx emission concentration to a certain extent.

[0082] Step 5: Based on the analysis results of Steps 2, 3, and 4, the following suggestions are made for flue gas pollutant emission reduction and operation optimization:

[0083] When starting the unit, under the premise of ensuring stable combustion, the operating fuel flow and the opening of the combustion chamber bypass valve should be reduced as much as possible to reduce NOx emissions during the unit's speed-up process; to reduce SO2 emissions during the start-up process, the temperature inside the gas turbine combustion chamber should be increased as much as possible, which can be achieved by increasing the natural gas preheating temperature.

[0084] When the unit is shut down, the operating fuel flow and the opening of the combustion chamber bypass valve should be reduced as much as possible while ensuring stable combustion to reduce NOx emissions during the unit load reduction process; to reduce SO2 emissions during the shutdown process, the opening of the combustion chamber bypass valve should be reduced as much as possible while ensuring stable combustion.

[0085] The most important factor affecting NOx emissions from gas turbines during stable operation is the shift fuel flow rate. When NOx emissions from gas turbines exceed the standard, the shift fuel flow rate can be appropriately reduced.

[0086] During cold start-up, while ensuring the safety and stability of the unit, reducing the amount of fuel on duty lowers the combustion chamber temperature to control the emission concentration of flue gas pollutants; optimizing the start-up time of cold start-up and shortening the duration of diffusion combustion under low load can reduce emissions.

[0087] The present invention also provides a system for a method of reducing pollutant emissions from a gas turbine combustion chamber, comprising,

[0088] The start-up state emission characteristics module is used to obtain the emission characteristics of gas turbine combustor flue gas pollutants under different start-up states based on the flue gas pollutant emission data of the gas turbine combustor under different start-up states.

[0089] The load-state emission characteristics module is used to acquire flue gas pollutant emission data of the gas turbine combustor under different load conditions, and obtain the flue gas pollutant emission characteristics of the gas turbine combustor under different load conditions;

[0090] The correlation analysis module is used to perform correlation analysis on the emission characteristics of flue gas pollutants from the gas turbine combustor under different start-up states and different load conditions, and to determine the factors that have the greatest impact on flue gas pollutant emissions.

[0091] The optimization module is used to optimize the operation of the gas turbine combustion chamber based on the factors that have the greatest impact on flue gas pollutant emissions, thereby reducing flue gas pollutant emissions.

[0092] The above content is only for illustrating the technical concept of the present invention and should not be construed as limiting the scope of protection of the present invention. Any modifications made to the technical solution based on the technical concept proposed in this invention shall fall within the scope of protection of the claims of this invention.

Claims

1. A method of flue gas pollutant abatement for a gas turbine combustor, characterized by, The method comprises the following steps: Step 1: Obtain the flue gas pollutant emission characteristics of the gas turbine combustor under different starting conditions according to the flue gas pollutant emission data of the gas turbine combustor under different starting conditions; Step 2: Obtain the flue gas pollutant emission characteristics of the gas turbine combustor under different load conditions according to the flue gas pollutant emission data of the gas turbine combustor under different load conditions; Step 3: Perform correlation analysis on the flue gas pollutant emission characteristics of the gas turbine combustor corresponding to different starting conditions and different load conditions and operating parameters by using a significance test method, and determine the factor that most affects the flue gas pollutant emission; The operating parameters include: gas turbine load, on-duty fuel flow control valve opening degree, combustor bypass valve opening degree and combustor outlet temperature; The flue gas pollutant emission characteristics of the combustor are the variation rules of the flue gas pollutant parameters with time; The significance test method is as follows: Determine the correlation coefficient between two flue gas pollutant emission characteristics and operating parameters according to the pearson sum-difference correlation coefficient method, construct a statistic t according to the correlation coefficient, calculate the significance probability p by combining the TDIST function, analyze the correlation of the two flue gas pollutant emission characteristics according to the significance probability p, and determine the factor that most affects the flue gas pollutant emission; The calculation method of the correlation coefficient is as follows: wherein , is the sample data of the parameter variable under investigation, , is the average value of the respective sample data; Step 4: Optimize the operation process of the gas turbine combustor according to the factor that most affects the flue gas pollutant emission, and reduce the emission of the flue gas pollutant.

2. A method of reducing flue gas pollutant emissions from a gas turbine combustor according to claim 1, wherein, The different starting conditions include cold starting, warm starting and hot starting; The warm starting includes cold-warm starting and hot-warm starting; The hot starting includes normal hot starting and extremely hot starting.

3. A method of reducing flue gas pollutant emissions from a gas turbine combustor according to claim 1, wherein, The different load conditions in step 2 include the load variation during the whole process from starting to stable load to shutdown of the gas-steam combined cycle unit; The stable load is the full load condition of the gas-steam combined cycle unit.

4. A method of reducing flue gas pollutant emissions from a gas turbine combustor according to claim 1, wherein, The expression of the statistic t is as follows: In the formula, n is the sample number, and r is the correlation coefficient.

5. A method of reducing flue gas pollutant emissions from a gas turbine combustor according to claim 4, wherein, The expression of the significance probability p is as follows: p=TDIST(t,n-2,2).

6. A system for performing the method of abatement of flue gas pollutants from a combustion chamber of a gas turbine according to any one of claims 1-5, characterized in that, The method comprises the following steps: The starting state emission characteristic module is configured to obtain the flue gas pollutant emission characteristics of the gas turbine combustor under different starting conditions according to the flue gas pollutant emission data of the gas turbine combustor under different starting conditions; The load state emission characteristic module is configured to obtain the flue gas pollutant emission characteristics of the gas turbine combustor under different load conditions according to the flue gas pollutant emission data of the gas turbine combustor under different load conditions; The correlation analysis module is configured to perform correlation analysis on the flue gas pollutant emission characteristics of the gas turbine combustor corresponding to different starting conditions and different load conditions and operating parameters, and determine the factor that most affects the flue gas pollutant emission; The optimization module is configured to optimize the operation process of the gas turbine combustor according to the factor that most affects the flue gas pollutant emission, and reduce the emission of the flue gas pollutant.

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