A selection method and device for removing nitrogen oxides from power station flue gas

Abstract

The present invention belongs to the technical field of flue gas emission, and discloses a selection method and device for removing nitrogen oxides from flue gas of a power station, the method comprising: collecting flue gas data after being treated by a selective catalytic reduction method and a selective non-catalytic reduction method to remove nitrogen oxides; respectively calculating the nitrogen oxide removal rate, energy consumption index and operation stability index of the nitrogen oxide removal rate of the selective catalytic reduction method and the selective non-catalytic reduction method; calculating the weight of each single index by a comprehensive weighting method, and calculating a comprehensive score; comparing the comprehensive scores of the selective catalytic reduction method and the selective non-catalytic reduction method, and selecting a method with a high comprehensive score and each single index being better than the other method as a method for removing nitrogen oxides from flue gas of a power station. The present invention can accurately evaluate the performance of the selective catalytic reduction method and the selective non-catalytic reduction method in removing nitrogen oxides from flue gas of a power station, and provide a scientific basis for selecting a suitable denitrification technology for a power station.

Description

Technical Field

[0001] The invention belongs to the technical field of flue gas emission, and in particular relates to a selection method and a device for removing nitrogen oxides from flue gas in a power station. Background Art

[0002] With increasingly stringent environmental protection requirements, the emission control of nitrogen oxides in the flue gas of coal-fired power plants has become an important task. At present, selective catalytic reduction (SCR) and selective non-catalytic reduction (SNCR) technologies are commonly used technologies for nitrogen oxide removal. However, for different power plant operating conditions and flue gas conditions, there are differences in the removal effects of the two technologies. Therefore, an effective evaluation method and system are needed to accurately evaluate the performance of different technologies in removing nitrogen oxides from power plant flue gas. The existing evaluation method for nitrogen oxide removal measures the nitrogen oxide concentration before and after the nitrogen oxide removal treatment and calculates the denitrification efficiency and measures the evaluation of various indicators at the outlet of the nitrogen oxide removal system independently, which cannot be comprehensively evaluated, making the evaluation results too one-sided, which is not conducive to selecting a nitrogen oxide removal scheme that maximizes economic and environmental benefits.

[0003] The Chinese patent publication number is CN118518816A, and the name is a patent application for a flue gas emission risk assessment method and early warning system based on flue gas purification working conditions. The assessment method obtains the mean value Vf(t1) of the vibration signal of the atomizer within the continuous time t1; the mean value Pd(t2) of the pressure difference of the bag filter within the continuous time t2; and the mean value Ma of the amount of activated carbon per ton of garbage within the continuous time t3, and compares them with the corresponding early warning values, respectively, to determine whether the terminal flue gas has a risk of exceeding the emission standard. If Vf(t1) or Pd(t2) exceeds the early warning value, or Ma is lower than the threshold, it is determined that the terminal flue gas emission has a risk of exceeding the pollutant standard, and corresponding adjustments are made to prevent the flue gas emission from exceeding the standard. The flue gas emission early warning system based on the flue gas purification working conditions can provide early warnings in the flue gas purification link, guide the waste incineration plant to make adjustments as soon as possible, and avoid terminal emissions exceeding the standard. However, the assessment method of the patent application cannot solve the problem of selecting nitrogen oxides for removal from power plant flue gas. Summary of the invention

[0004] In order to overcome the problems existing in the above-mentioned prior art, the purpose of the present invention is to provide a selection method and device for removing nitrogen oxides from power plant flue gas, accurately evaluate the performance of selective catalytic reduction method and selective non-catalytic reduction method in removing nitrogen oxides from power plant flue gas, and provide a scientific basis for selecting appropriate denitrification technology for power plants.

[0005] To achieve the above object, the technical solution adopted by the present invention is: In a first aspect, the present invention provides a method for removing nitrogen oxides from flue gas of a power station, comprising the following steps: Collect flue gas data after the removal of nitrogen oxides by selective catalytic reduction and selective non-catalytic reduction methods; Calculate the nitrogen oxide removal rate, energy consumption index and operation stability index of the nitrogen oxide removal rate of the selective catalytic reduction method and the selective non-catalytic reduction method respectively; The weight of each single indicator is calculated by comprehensive weighting method, and the calculation results of each single indicator are added with comprehensive weights and then accumulated to calculate the comprehensive score; The comprehensive scores of the selective catalytic reduction method and the selective non-catalytic reduction method are compared, and the method with a high comprehensive score and each single indicator is better than the other method is selected as the method for removing nitrogen oxides from power plant flue gas.

[0006] Optionally, after collecting the flue gas data, outliers are removed from the data, and the data are smoothed and normalized.

[0007] Optionally, the nitrogen oxide removal rate by the selective catalytic reduction method is the percentage of the difference between the nitrogen oxide concentration at the inlet and the nitrogen oxide concentration at the outlet of the selective catalytic reduction method nitrogen oxide removal device to the nitrogen oxide concentration at the inlet of the selective catalytic reduction method nitrogen oxide removal device; the nitrogen oxide removal rate by the selective non-catalytic reduction method is the percentage of the difference between the nitrogen oxide concentration at the inlet and the nitrogen oxide concentration at the outlet of the selective non-catalytic reduction method nitrogen oxide removal device to the nitrogen oxide concentration at the inlet of the selective non-catalytic reduction method nitrogen oxide removal device.

[0008] Optionally, the energy consumption index of the selective catalytic reduction method includes catalyst energy consumption, calculation heating system energy consumption and fan energy consumption; the energy consumption index of the selective non-catalytic reduction method includes reducing agent energy consumption and injection system energy consumption.

[0009] Optionally, the operational stability assessment considers factors including equipment failure rate, maintenance frequency and catalyst activity change rate.

[0010] Optionally, the comprehensive weighting method adopts a combination of triangular fuzzy hierarchical analysis method and entropy weight method to determine the comprehensive weight of each indicator, determines the subjective weight by hierarchical analysis method, determines the objective weight by entropy weight method, obtains the comprehensive weight by comprehensive weighting, and calculates the comprehensive score according to the calculation results of each indicator and the comprehensive weight.

[0011] In a second aspect, the present invention provides a selective system for removing nitrogen oxides from flue gas of a power station, comprising: A data acquisition module, used to collect flue gas data after the treatment of removing nitrogen oxides by the selective catalytic reduction method and the selective non-catalytic reduction method; A single index analysis module, used to calculate the nitrogen oxide removal rate, energy consumption index and operation stability index of the nitrogen oxide removal rate of the selective catalytic reduction method and the selective non-catalytic reduction method respectively; The multi-index comprehensive analysis module is used to calculate the weight of each single index through the comprehensive weighting method, add the comprehensive weight to the calculation results of each single index, and then add them up to calculate the comprehensive score; The comparison and selection module is used to compare the comprehensive scores of the selective catalytic reduction method and the selective non-catalytic reduction method, and select the evaluation method with a high comprehensive score and each single indicator is better than the other method as the selection method for removing nitrogen oxides from power plant flue gas.

[0012] In a third aspect, the present invention provides an electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements a method for selecting nitrogen oxides removed from flue gas of the power station when executing the computer program.

[0013] In a fourth aspect, the present invention provides a computer-readable storage medium storing a computer program, which, when executed by a processor, implements a method for selecting the removal of nitrogen oxides from flue gas of the power station.

[0014] In a fifth aspect, the present invention provides a computer program product comprising a computer-readable medium, on which a computer-readable program code is contained, and the program code executes the method for selecting the removal of nitrogen oxides from the flue gas of the power station.

[0015] Compared with the prior art, the present invention has the following beneficial effects: The present invention can accurately evaluate the performance of selective catalytic reduction method and selective non-catalytic reduction method in removing nitrogen oxides in power plant flue gas, and provide a scientific basis for selecting appropriate denitrification technology for power plants; comprehensively evaluate the indicators of nitrogen oxide removal rate, energy consumption, and operational stability to maximize economic and environmental benefits.

[0016] The evaluation method and system provided by the present invention can accurately evaluate the performance of the selective catalytic reduction method and the selective non-catalytic reduction method in removing nitrogen oxides from power plant flue gas, and provide a scientific basis for selecting appropriate denitrification technology for power plants.

[0017] The present invention comprehensively evaluates the indicators of nitrogen oxide removal rate, energy consumption and operation stability, compares the evaluation results of the two technologies, and provides a reliable basis for maximizing economic and environmental benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The drawings described herein are for illustration purposes only and are not intended to limit the scope of the present disclosure in any way.

[0019] In the attached picture: Figure 1 The present invention is a flow chart of the steps of the method for removing nitrogen oxides from power plant flue gas. DETAILED DESCRIPTION

[0020] In order to enable those skilled in the art to better understand the technical solutions in the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0021] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which the present invention belongs. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0022] It should be noted that in the claims, any reference signs placed between brackets shall not be construed as limiting the claims. The word "comprising" does not exclude the presence of components or steps not listed in the claims. The word "a" or "an" preceding a component does not exclude the presence of a plurality of such components. The present application may be implemented by means of hardware comprising several different components and by means of a suitably programmed computer. In a unit claim enumerating several means, several of these means may be embodied by the same item of hardware. The use of the words first, second, and third etc. does not indicate any order. These words may be interpreted as names. In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined. The present invention is described in detail below with reference to the accompanying drawings.

[0023] A selective method for removing nitrogen oxides from power plant flue gas of the present invention comprises the following steps: Collect flue gas data after the removal of nitrogen oxides by selective catalytic reduction and selective non-catalytic reduction methods; Calculate the nitrogen oxide removal rate, energy consumption index and operation stability index of the nitrogen oxide removal rate of the selective catalytic reduction method and the selective non-catalytic reduction method respectively; The weight of each single indicator is calculated by comprehensive weighting method, and the calculation results of each single indicator are added with comprehensive weights and then accumulated to calculate the comprehensive score; The comprehensive scores of the selective catalytic reduction method and the selective non-catalytic reduction method are compared, and the method with a high comprehensive score and each single indicator is better than the other method is selected as the method for removing nitrogen oxides from power plant flue gas.

[0024] The present invention can accurately evaluate the performance of selective catalytic reduction method and selective non-catalytic reduction method in removing nitrogen oxides in power plant flue gas, and provide a scientific basis for selecting appropriate denitrification technology for power plants; comprehensively evaluate the indicators of nitrogen oxide removal rate, energy consumption, and operational stability to maximize economic and environmental benefits.

[0025] Example 1 Combine the following Figure 1 The specific implementation modes of the present invention are further described.

[0026] A selection system for removing nitrogen oxides from power station flue gas comprises: a flue gas sampling device, a nitrogen oxide removal device, a data acquisition and preprocessing module, a single index analysis module, a multi-index comprehensive analysis module, a comparison selection module and a display module.

[0027] Selective catalytic reduction and selective non-catalytic reduction are used to remove nitrogen oxides from flue gas: In the selective catalytic reduction method, ammonia is sprayed into the high-temperature flue gas as a reducing agent, and reacts with NOx under the action of a catalyst. The catalyst can accelerate the reaction rate, so that NOx and ammonia can undergo an effective reduction reaction at a lower temperature, and the nitrogen and water vapor generated by the reaction are subsequently discharged into the atmosphere; this reaction usually takes place in the temperature range of 200℃~450℃ and has a high denitrification efficiency.

[0028] The selective non-catalytic reduction method does not require a catalyst. Ammonia water or urea solution is sprayed into the high-temperature flue gas to undergo a non-selective reduction reaction with NOx to generate nitrogen and water vapor, which are then discharged into the atmosphere. Since there is no accelerating effect of a catalyst, the reaction temperature of the selective non-catalytic reduction method is usually high, and the denitrification efficiency and ammonia escape rate are relatively low.

[0029] Data acquisition module: used to collect flue gas parameters after the selective catalytic reduction method and the selective non-catalytic reduction method to remove nitrogen oxides, and to perform pretreatment. The flue gas sampling device collects representative flue gas samples from the flue of the coal-fired power plant. The flue gas sampling device uses an automatic sampling system to automatically sample according to the preset time interval and flue gas parameter changes; the sampling position should reflect the overall condition of the flue gas in the flue; the sampling process should avoid significant impact on the flue gas flow and composition.

[0030] The sensors of the data acquisition module include nitrogen oxide sensors, flow meters, thermal resistance sensors and pressure sensors, which measure nitrogen oxide concentration, flue gas flow, temperature and pressure; The data preprocessing includes removing outliers, data smoothing and normalization processing; Remove outliers: Use the 3σ criterion statistical method to identify and remove data points that are significantly out of the normal range; calculate their mean and standard deviation. , mean , where n is the number of data points, and the standard deviation , where ∑ represents the sum, for each data point Xᵢ, if , then the data point is considered to be an outlier.

[0031] Data smoothing: Use the moving average method to smooth the data by calculating the average value of the data points within a certain window size; Calculation process: Select the window size as m, then for the data sequence , the smoothed data series is ,in .

[0032] Normalization: Map data of different dimensions to a specified interval so that data of different dimensions have the same scale; for parameter sets , the data sequence after linear normalization is ,in , Xmin is the minimum value in the data set, and Xmax is the maximum value in the data set.

[0033] Single index analysis module: used to analyze and evaluate various indicators of the selective catalytic reduction method and the selective non-catalytic reduction method, including: nitrogen oxide removal rate, energy consumption, equipment investment cost, and operation stability.

[0034] When calculating the final weights of each indicator, the energy consumption indicator and cost capital are divided by the preset maximum value and then multiplied by the percentage, with the unified unit being percentage.

[0035] The calculation of nitrogen oxide removal rate includes the calculation of nitrogen oxide removal rate by selective catalytic reduction method and the calculation of nitrogen oxide removal rate by selective non-catalytic reduction method; Calculation of nitrogen oxide removal rate by selective catalytic reduction method: The nitrogen oxide concentration at the inlet of the selective catalytic reduction method to remove nitrogen oxides is Cscr,in, and the nitrogen oxide concentration at the outlet is Cscr,out. The nitrogen oxide removal rate of the selective catalytic reduction method is .

[0036] Calculation of nitrogen oxide removal rate by selective non-catalytic reduction method: Assuming that the concentration of nitrogen oxides at the inlet of the selective non-catalytic reduction method for removing nitrogen oxides is Csncr,in, and the concentration of nitrogen oxides at the outlet is Csncr,out, the nitrogen oxide removal rate of the selective non-catalytic reduction method is .

[0037] Energy consumption calculation of selective catalytic reduction method: Catalyst energy consumption is calculated based on the amount of catalyst used and energy consumption. Assuming the amount of catalyst used is Mscr,catalyst and the energy consumption per unit mass of catalyst is Escr,catalyst, then the catalyst energy consumption is .

[0038] Calculate the energy consumption of the heating system. Assume that the power of the heating system is Pscr,heating and the operating time is tscr,heating. Then the energy consumption of the heating system is .

[0039] The fan energy consumption can be calculated based on the fan power and running time; assuming the fan power is Pscr,fan and the running time is tscr,fan, the fan energy consumption is .

[0040] Combining the above energy consumption, the total energy consumption of the selective catalytic reduction method is .

[0041] Energy consumption calculation of selective non-catalytic reduction method: The energy consumption of reducing agent is calculated based on the amount of reducing agent used and the energy consumption. Assuming the amount of reducing agent used is Msncr,reductant and the energy consumption per unit mass of reducing agent is Esncr,reductant, the energy consumption of reducing agent is: .

[0042] Energy consumption of injection system. Assuming the power of injection system is Psncr,injection and the operation time is tsncr,injection, the energy consumption of injection system is .

[0043] Combining the above energy consumption, the total energy consumption of the selective non-catalytic reduction method is .

[0044] The equipment investment cost assessment includes the construction cost of the nitrogen oxide removal device and the purchase cost of the catalyst and the reducing agent.

[0045] Equipment investment cost of selective catalytic reduction method: Calculate the equipment investment cost. Assume the construction cost of the nitrogen oxide removal device Cscr,construction, the purchase cost of the catalyst Cscr,catalyst,purchase, and the cost of other related equipment Cscr,other; then the equipment investment cost is .

[0046] Equipment investment cost of selective non-catalytic reduction method: Calculate the equipment investment cost. Assume that the construction cost of the nitrogen oxide removal device is Csncr,construction, the purchase cost of the reductant is Csncr,reductant,purchase, and the cost of other related equipment is Csncr,other. Then the equipment investment cost is .

[0047] The operational stability assessment considers factors including equipment failure rate, maintenance frequency and catalyst activity change rate.

[0048] Calculate the equipment failure rate: Assume that the number of failures of the selective catalytic reduction method for removing nitrogen oxides is Nscr,failure, and the operating time is Tscr,total, then the failure rate of the selective catalytic reduction method is Similarly, suppose the number of failures of the selective non-catalytic reduction technology nitrogen oxide removal device is N sncr,failure , the running time is T sncr,total , then the failure rate of the selective non-catalytic reduction method is .

[0049] Calculate the maintenance frequency: Assume that the maintenance times of the selective catalytic reduction nitrogen oxide removal device are Nscr,maintenance, and the total maintenance time is Tscr,maintenance. Then the maintenance frequency of the selective catalytic reduction nitrogen oxide removal device is Similarly, the maintenance frequency of the selective non-catalytic reduction method for removing nitrogen oxides is calculated ; Calculate the catalyst activity change rate: Activity change rate ; Selective non-catalytic reduction method, without catalyst.

[0050] The initial activity of the catalyst is Ascr,initia, dimensionless; The activity after a period of operation is Ascr,current, expressed in percentage.

[0051] Multi-index comprehensive analysis module: used to calculate the weight of each single indicator using the comprehensive weighting method, and calculate the comprehensive score based on the calculation results and weights of each indicator. The evaluation results are transmitted to the display module and displayed to the user in an intuitive way. The comprehensive weighting method uses a combination of triangular fuzzy hierarchical analysis method and entropy weight method to determine the comprehensive weight of each indicator. The subjective weight is determined by the hierarchical analysis method, the objective weight is determined by the entropy weight method, and the comprehensive weight is obtained by comprehensive weighting. The comprehensive score is calculated based on the calculation results and comprehensive weights of each indicator.

[0052] Triangular fuzzy analytic hierarchy process to determine subjective weights: Construct a triangular fuzzy judgment matrix and invite experts to compare the indicators in pairs. The indicators can be represented by triangular fuzzy numbers (l, m, u), where l represents the minimum possible value, m represents the most likely value, and u represents the maximum possible value. According to the importance, a 4*4 triangular fuzzy judgment matrix A={aij} is constructed, where aij represents the importance of the i-th factor relative to the j-th factor. ; Calculate the fuzzy weight vector, and for each row element in the fuzzy judgment matrix A, calculate its geometric mean , where n=4 is the number of indicators, the geometric mean vector Perform normalization to obtain the fuzzy weight vector of the indicator ,in .

[0053] Defuzzification, calculate the optimistic weight, pessimistic weight and most likely weight, and for each triangular fuzzy number (l, m, u) in the fuzzy weight vector w, calculate its optimistic weight wi, optimistic = u, pessimistic weight wi, pessimistic = l and most likely weight wi most likely = m respectively. Use different methods to determine the comprehensive weight and take the average of the optimistic weight, pessimistic weight and most likely weight, that is, , and obtain the subjective weight vector . Perform consistency check to determine whether the matrix has satisfactory consistency; first calculate the fuzzy consistency matrix of the triangular fuzzy judgment matrix A ,in , calculate the fuzzy consistency index ,in ; Calculate the fuzzy random consistency index RI. For a 4-order matrix, RI has a specific value that can be found; Calculate the consistency ratio ,If CR<0.1, the judgment matrix is ​​considered to have satisfactory consistency, otherwise the ,judgment matrix needs to be adjusted.

[0054] The entropy weight method determines the objective weight: For benefit indicators, Standardization is performed, where xab represents the bth indicator value of the ath evaluation object, maxbxab represents the maximum value of the bth indicator among all evaluation objects, and minbxab represents the minimum value of the bth indicator among all evaluation objects; for cost-type indicators, the formula is used Standardize; calculate the entropy value of the indicator. For the bth indicator, calculate its entropy value eb. First calculate the probability distribution of indicator b , where c is the number of nitrogen oxide removal schemes, c=2, and then calculate the information entropy of index b ,in ; Determine the weight and calculate the weight of the bth indicator based on the entropy value , and obtain the objective weight vector ; Benefit-based indicators refer to indicators where the larger the value, the better, including nitrogen oxide removal rate; Cost-based indicators are those where the smaller the value, the better, including energy consumption, equipment investment cost and operational stability.

[0055] Comprehensive empowerment determines the comprehensive weight: Determine the combination coefficient. According to the actual situation and expert experience, determine the combination coefficients α and β of the subjective weight obtained by the hierarchical analysis method and the objective weight obtained by the entropy weight method, and satisfy α+β=1; calculate the comprehensive weight, the comprehensive weight of nitrogen oxide removal efficiency , the comprehensive weight of energy consumption , the comprehensive weight of equipment investment cost , comprehensive evaluation of operational stability .

[0056] Calculate the overall assessment score: For the selective catalytic reduction method, the comprehensive evaluation score is:

[0057] For the selective non-catalytic reduction method, the comprehensive evaluation score is:

[0058] Among them, Etotal,max is the preset maximum energy consumption value, and Ctotal,max is the preset maximum equipment investment cost value.

[0059] Display module: used to output the evaluation results to the display module and present them to the user in an intuitive manner, including: transmitting the nitrogen oxide removal rate, energy consumption, equipment investment cost, operation stability and comprehensive evaluation score information of the evaluation results to the display module, organizing the transmitted data information into a clear data table or chart form, and presenting it to the user. The user compares the performance differences between the selective catalytic reduction method and the selective non-catalytic reduction method according to the evaluation results and makes a reasonable choice.

[0060] Comparison selection module: used to collect the comprehensive score of the multi-index comprehensive analysis module or the comprehensive score displayed by the display module, and compare the comprehensive scores: directly compare the comprehensive scores of the SCR method and the SNCR method. If the comprehensive score of one method is significantly higher than that of another method, and each single indicator (nitrogen oxide removal rate, energy consumption, equipment investment cost, and operating stability) is better than the single indicator of another method, then this method is preferred. When the SCR method has a high comprehensive score and performs better than the SNCR method in terms of removal rate, energy consumption, and operating stability, then the SCR method is selected.

[0061] While the two methods each have their own outstanding advantages, they need to be weighed based on the specific needs and actual conditions of the power plant.

[0062] Choose one of the methods that has advantages in certain aspects to suit the specific situation.

[0063] If the power station is located in an area with strict environmental protection requirements, a method with a higher nitrogen oxide removal rate should be selected.

[0064] If the power station is under great pressure from operating costs, choose a method with lower energy consumption.

[0065] If the power plant lacks initial investment costs, then choose a method with lower equipment investment costs.

[0066] If the power station is not easy to maintain, choose a method with high operational stability.

[0067] Example 2 The purpose of this embodiment is to provide an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements a method for selecting nitrogen oxides removed from flue gas of the power station when executing the computer program.

[0068] Example 3 The purpose of this embodiment is to provide a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the selection method for removing nitrogen oxides from the flue gas of the power station is implemented.

[0069] Example 4 The purpose of this embodiment is to provide a computer program product including a computer-readable medium, on which a computer-readable program code is contained, and the program code executes the selection method for removing nitrogen oxides from the flue gas of the power station.

[0070] The steps and methods involved in the devices of the above embodiments 2, 3 and 4 correspond to those of embodiment 1. For the specific implementation methods, please refer to the relevant description part of embodiment 1.

[0071] It should be understood by those skilled in the art that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present application may adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program codes. The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks. These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes. These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process in the computer or other programmable device. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0072] Unless otherwise specified, the working modes or control modes involved in the above embodiments are all conventional working modes or control modes in the art.

[0073] Although the preferred embodiments of the present application have been described, those skilled in the art may make other changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications falling within the scope of the present application. Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Other modifications or equivalent substitutions made to the technical solution of the present invention by ordinary technicians in the field should be included in the scope of the claims of the present invention as long as they do not depart from the spirit and scope of the technical solution of the present invention.

Claims

1. A method for removing nitrogen oxides from power plant flue gas, characterized in that: The following steps are involved: Collect flue gas data after the removal of nitrogen oxides by selective catalytic reduction and selective non-catalytic reduction methods; Calculate the nitrogen oxide removal rate, energy consumption index and operation stability index of the nitrogen oxide removal rate of the selective catalytic reduction method and the selective non-catalytic reduction method respectively; The weight of each single indicator is calculated by comprehensive weighting method, and the calculation results of each single indicator are added with comprehensive weights and then accumulated to calculate the comprehensive score; The comprehensive scores of the selective catalytic reduction method and the selective non-catalytic reduction method are compared, and the method with a high comprehensive score and each single indicator is better than the other method is selected as the method for removing nitrogen oxides from power plant flue gas.

2. The method for removing nitrogen oxides from power plant flue gas according to claim 1, characterized in that: After collecting the flue gas data, outliers are removed, and the data are smoothed and normalized.

3. The method for removing nitrogen oxides from power plant flue gas according to claim 1, characterized in that: The nitrogen oxide removal rate by the selective catalytic reduction method is the percentage of the difference between the nitrogen oxide concentration at the inlet and the nitrogen oxide concentration at the outlet of the selective catalytic reduction method nitrogen oxide removal device to the nitrogen oxide concentration at the inlet of the selective catalytic reduction method nitrogen oxide removal device; the nitrogen oxide removal rate by the selective non-catalytic reduction method is the percentage of the difference between the nitrogen oxide concentration at the inlet and the nitrogen oxide concentration at the outlet of the selective non-catalytic reduction method nitrogen oxide removal device to the nitrogen oxide concentration at the inlet of the selective non-catalytic reduction method nitrogen oxide removal device.

4. The method for removing nitrogen oxides from power plant flue gas according to claim 1, characterized in that: The energy consumption indicators of the selective catalytic reduction method include catalyst energy consumption, calculation heating system energy consumption and fan energy consumption; the energy consumption indicators of the selective non-catalytic reduction method include reducing agent energy consumption and injection system energy consumption.

5. The method for removing nitrogen oxides from power plant flue gas according to claim 1, characterized in that: The operational stability assessment considers factors including equipment failure rate, maintenance frequency and catalyst activity change rate.

6. The method for removing nitrogen oxides from flue gas of a power station according to claim 1, characterized in that: The comprehensive weighting method combines the triangular fuzzy analytic hierarchy process with the entropy weight method to determine the comprehensive weight of each indicator. The subjective weight is determined by the analytic hierarchy process, and the objective weight is determined by the entropy weight method. The comprehensive weight is obtained by comprehensive weighting, and the comprehensive score is calculated based on the calculation results of each indicator and the comprehensive weight.

7. A selective system for removing nitrogen oxides from power plant flue gas, characterized in that: include: A data acquisition module, used to collect flue gas data after the treatment of removing nitrogen oxides by the selective catalytic reduction method and the selective non-catalytic reduction method; A single index analysis module, used to calculate the nitrogen oxide removal rate, energy consumption index and operation stability index of the nitrogen oxide removal rate of the selective catalytic reduction method and the selective non-catalytic reduction method respectively; The multi-index comprehensive analysis module is used to calculate the weight of each single index through the comprehensive weighting method, add the comprehensive weight to the calculation results of each single index, and then add them up to calculate the comprehensive score; The comparison and selection module is used to compare the comprehensive scores of the selective catalytic reduction method and the selective non-catalytic reduction method, and select the evaluation method with a high comprehensive score and each single indicator is better than the other method as the selection method for removing nitrogen oxides from power plant flue gas.

8. An electronic device, characterized in that: The invention comprises a memory, a processor and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, the method for selecting nitrogen oxides for removing from flue gas of a power station as claimed in any one of claims 1 to 6 is implemented.

9. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the method for selecting nitrogen oxides for removing from power plant flue gas according to any one of claims 1 to 6 is implemented.

10. A computer program product comprising a computer readable medium, characterized in that The computer-readable medium contains computer-readable program code, and the program code executes the selection method for removing nitrogen oxides from power plant flue gas as described in any one of claims 1-6.

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