Nitrous oxide emission reduction control system and method for SCR (Selective Catalytic Reduction) denitration device

Abstract

The invention relates to the technical field of environment-friendly emission of coal-fired power plants, and particularly discloses a nitrous oxide emission reduction control system and method for an SCR denitration device. The denitration inlet flue gas parameter monitoring module and the denitration outlet flue gas parameter monitoring module are arranged at an inlet and an outlet of the denitration device; the ammonia spraying flow adjusting device, the denitration ammonia nitrogen mixing device, the catalyst interlayer temperature collecting system and the denitration outlet flue gas parameter monitoring module are sequentially arranged in the denitration device according to the flue gas output direction. The control system further comprises a data analysis and decision module system. The system is used for monitoring and controlling the nitrous oxide emission concentration of a denitration device, optimal process parameters are calculated and set, a control system is input to adjust the chemical reaction component proportion and the reaction temperature, the denitration reaction is promoted to generate nitrogen, the yield of greenhouse gas nitrous oxide is reduced, and nitrous oxide emission reduction control is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of environmental protection emission of coal-fired power plants, and in particular to a nitrous oxide emission reduction control system and method for an SCR denitration device. Background Art

[0002] Nitrous oxide (N2O) is a greenhouse gas. Nitrous oxide in the atmosphere is generated from the ocean and soil by microorganisms. With the development of human activities and industry and agriculture, the concentration of N2O in the atmosphere has shown a rapid growth trend. The emission of N2O is similar to that of carbon dioxide (CO2). Both are produced with the combustion of fossil fuels. Thermal power plants are one of its main emission sources. Although the total amount of N2O is small, about 0.003ppm, its harm to the atmosphere is similar to that of chlorofluorocarbons, and it has a scavenging effect on the ozone layer. The combustion of fossil fuels and flue gas denitrification can cause different degrees of increase in nitrous oxide concentration.

[0003] Taking a 300MW unit as an example, the volume concentration of N2O emissions is about 5~20ppm depending on the operating conditions, and the mass concentration under standard conditions is 9.82~39.29mg / m3. Calculated based on the full-load operation of the unit for 8,000 hours throughout the year, the N2O emissions are about 94~377 tons, which is only 0.17% of CO2. However, considering the single-molecule warming potential GWP of nitrous oxide, the Global Warming Potential is 310 times that of CO2, and the greenhouse effect caused is 13~53% of CO2. It can be seen that the greenhouse effect caused by nitrous oxide emissions from thermal power plants cannot be underestimated. In-depth research on the generation mechanism of N2O and further development of emission reduction control technology will become a breakthrough point in controlling the global greenhouse effect. Selective catalytic reduction (SCR) is the most widely used flue gas denitrification technology in the world. The main principle of this technology is to introduce a reducing agent to catalytically reduce NOx into H2O and N2 under the action of a catalyst. At the same time, the side reactions of the SCR denitrification reaction in thermal power plants will intensify. As a greenhouse gas, real-time monitoring and emission control of N2O are urgent.

[0004] In the prior art, the nitrous oxide emission reduction control methods for SCR denitrification devices are mainly based on the improvement of chemical methods, which are all disposable consumables. For example, the activity of nitrous oxide reductase is inhibited to keep the reaction product in the nitrous oxide stage; there is a lack of multiple recycling emission reduction control methods achieved by intelligent monitoring and control; based on this, technical personnel in this field are in urgent need of a special equipment that is suitable for the comprehensive reduction of greenhouse gas emissions and can be recycled multiple times. Summary of the invention

[0005] Therefore, the technical problem to be solved by the present invention is to overcome the defects existing in the above-mentioned prior art, thereby providing a nitrous oxide emission reduction control system and method for an SCR denitration device.

[0006] A nitrous oxide emission reduction control system for an SCR denitration device, comprising: A flue gas temperature regulating device is installed at the inlet of the control system; A denitration inlet flue gas parameter monitoring module provided at the inlet of the denitration device and a denitration outlet flue gas parameter monitoring module provided at the outlet of the denitration device; And the pipeline connection of the ammonia injection flow regulating device, the denitrification ammonia nitrogen mixing device, the catalyst interlayer temperature acquisition system and the denitrification outlet flue gas parameter monitoring module which are arranged in sequence according to the flue gas output direction in the denitrification device; The control system also includes: a data analysis and decision-making model system connected with the denitrification inlet flue gas parameter monitoring module, the catalyst interlayer temperature acquisition system, the denitrification outlet flue gas parameter monitoring module and the nitrous oxide analyzer by two-way signals.

[0007] Preferably, the denitrification ammonia nitrogen mixing device is arranged in the inlet flue of the denitrification device, specifically: A disc device is installed above the ammonia spray grid of the denitrification ammonia nitrogen mixing device, so that when the flue gas and ammonia flow through the denitrification ammonia nitrogen mixing device, a variety of vortex streets will be generated on the leeward side of the disc device, thereby enhancing the mixing rate of ammonia and flue gas.

[0008] A method for reducing nitrous oxide emissions from an SCR denitration device is implemented by using a nitrous oxide emission reduction control system for the SCR denitration device. The method comprises the following steps: S1. Determine the optimal process control parameters for suppressing N2O generation based on the historical inlet and outlet flue gas parameters of the denitrification device of the unit and the historical operation status of the equipment: ammonia nitrogen ratio of 0.99 and flue gas temperature of 310-360 degrees; S2. Obtaining real-time operation data of the denitrification device, and executing step S3 and step S4 synchronously or executing one of step S3 and step S4 separately based on the real-time operation data of the denitrification device; S3. Calculate the actual ammonia nitrogen ratio based on the data obtained in step S2, and determine whether it is greater than 0.99; and further control the ammonia nitrogen ratio based on the result until the ammonia nitrogen ratio = 0.99; S4. Calculate whether the flue gas temperature obtained in step S2 is within the optimal range of 310-360 degrees, and control the flue gas temperature based on the calculation result until the flue gas temperature is no longer within the range of 310-360 degrees; S5. Measure N2O at the outlet of the denitrification device; S6. Determine whether the N2O concentration meets the preset requirements: if so, the method is terminated; if not, proceed to step S2; The loop feedback dynamic adjustment steps: S3-S6 are executed based on data analysis and decision-making model system.

[0009] Preferably, step S3 calculates the actual ammonia nitrogen ratio based on the data obtained in step S2, and determines whether it is greater than 0.99; and further controls the ammonia nitrogen ratio based on the result, specifically: The actual ammonia nitrogen ratio is calculated based on the data obtained in step S2, and it is determined whether it is greater than 0.99: If yes, reduce the ammonia spraying amount of the ammonia spraying flow regulating device, adjust the blade attitude angle of the denitrification ammonia nitrogen mixing device, and execute step 5 after the ammonia nitrogen ratio reaches 0.99; If not, on the basis of monitoring that ammonia escape does not exceed the standard, increase the ammonia spray amount of the ammonia spray flow regulating device, adjust the blade attitude angle of the denitrification ammonia nitrogen mixing device, until the ammonia nitrogen ratio = 0.99, and then execute step 5.

[0010] Preferably, S4. Calculate whether the flue gas temperature obtained in step S3 is within the optimal range of 310-360 degrees, and control the flue gas temperature based on the calculation result, specifically: If the flue gas temperature is within the range of 310-360 degrees, the flue gas temperature regulating device is used to regulate the flue gas temperature of the denitrification device until the flue gas temperature is lower than 310 degrees or higher than 360 degrees, and then step 5 is performed; If the flue gas temperature is lower than 310 degrees or higher than 360 degrees, proceed directly to step 5.

[0011] Preferably, S2. obtaining denitration device data includes: The denitrification inlet flue gas parameter monitoring module is used to measure the denitrification inlet flue gas flow rate, denitrification inlet nitrogen oxide concentration and ammonia injection flow rate in real time; The flue gas parameter monitoring module at the denitrification outlet is used to measure the flue gas flow rate at the denitrification outlet and the nitrogen oxide concentration at the denitrification outlet in real time, and the ammonia nitrogen molar ratio is further calculated; The catalyst interlayer temperature acquisition system is used to measure the operating temperature of each catalyst layer in real time and record historical operating data; The nitrous oxide analyzer is used to measure the N2O concentration at the denitrification outlet in real time, and the control results of the nitrous oxide emission reduction control method of the SCR denitrification device are fed back.

[0012] Preferably, it also includes: an adaptive iterative update method based on data analysis and decision model system implementation, specifically including: The data analysis and decision-making model system receives and stores the data transmitted by the nitrous oxide analyzer and generates a historical concentration data set; Iteratively and accurately optimize the control path of the SCR denitrification device nitrous oxide emission reduction control method based on the historical concentration data set; Based on the historical concentration data set, the preset requirements for N2O concentration at the denitrification outlet are accurately adapted to multiple levels.

[0013] The technical solution of the present invention has the following advantages: 1. The SCR denitration device nitrous oxide emission reduction control system provided by the present invention has a simple overall structure and can be used without major changes to the existing SCR denitration device structure. The present invention arranges an efficient ammonia nitrogen mixing device at the inlet of the denitration device to improve the mixing effect of nitrogen oxides and ammonia in the flue gas and increase the utilization rate of the reducing agent. At the same time, the present invention adjusts the blade posture of the ammonia nitrogen mixing device according to the load change of the unit and the measurement data of the nitrous oxide analyzer, alleviates ammonia escape caused by uneven ammonia spraying and helps control the generation of nitrous oxide.

[0014] 2. The nitrous oxide emission reduction control system of the SCR denitration device provided by the present invention realizes the display of nitrous oxide concentration and the warning of exceeding the standard through the data analysis and decision-making model system. At the same time, it can set the target value control value of the nitrous oxide concentration at the denitration outlet of several gears, and select the efficient and energy-saving path through the real-time feedback of the ammonia nitrogen molar ratio, the flue gas temperature and the nitrous oxide concentration at the denitration outlet, and comprehensively adjust the process parameters of the denitration reaction to achieve the purpose of rapid and high-quality nitrous oxide emission reduction control. In addition, based on the data analysis and decision-making model system, the user can continuously receive various process parameters of the denitration system and grasp the nitrous oxide emission concentration. By operating the system, the user can check, filter, store and export the flue gas parameters required by the user, and can calculate the maximum value, minimum value, average value, standard deviation and high-order data of the discreteness of each flue gas parameter in the entire flue section, and then form corresponding charts to realize the visualization of the measurement results for on-site analysis and equipment adjustment.

[0015] 3. The SCR denitration device nitrous oxide emission reduction control method provided by the present invention specifically provides two nitrous oxide emission reduction control methods: material balance adjustment and reaction temperature adjustment. (1) Based on the material ratio of the denitration reaction, the ammonia nitrogen molar ratio is calculated, and the ammonia nitrogen ratio is further adjusted to a slightly excess state through the ammonia injection flow adjustment device, and the nitrous oxide production is controlled by optimizing the material ratio. (2) Based on the denitration reaction temperature feedback from the catalyst interlayer temperature acquisition system, the reaction temperature is further adjusted to a reasonable range by the flue gas temperature adjustment device in a local adjustment manner, avoiding the temperature range that is conducive to the generation of nitrous oxide, and the nitrous oxide production is controlled by dynamically optimizing the denitration reaction temperature. The above two adjustment methods can be used in combination or separately, providing flexibility and convenience for system operation, and can also provide a more energy-saving solution under specific working conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0017] Figure 1 A schematic diagram of the specific position of the system of the present invention installed in a denitration device; Figure 2 It is a schematic diagram of the overall process of the method of the present invention; Figure 3 This is a schematic diagram of the system of the present invention.

[0018] Description of reference numerals: 1-Data analysis and decision-making model system; 2-Flue gas temperature control device; 3-Denitrification inlet flue gas parameter monitoring module; 4-Ammonia injection flow control device; 5-Denitrification ammonia nitrogen mixing device; 6-Catalyst interlayer temperature acquisition system; 7-Denitrification outlet flue gas parameter monitoring module; 8-Nitrous oxide analyzer. DETAILED DESCRIPTION

[0019] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. 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 are within the scope of protection of the present invention.

[0020] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0021] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0022] In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0023] Embodiment 1: like Figure 1 and 3 , a nitrous oxide emission reduction control system for an SCR denitration device, comprising: A flue gas temperature regulating device 2 is provided at the inlet of the control system; A denitration inlet flue gas parameter monitoring module 3 provided at the inlet of the denitration device and a denitration outlet flue gas parameter monitoring module 7 provided at the outlet of the denitration device; And the ammonia injection flow regulating device 4, the denitration ammonia nitrogen mixing device 5, the catalyst interlayer temperature acquisition system 6 and the denitration outlet flue gas parameter monitoring module 7 are arranged in sequence according to the flue gas output direction in the denitration device, and are connected by pipelines; The control system also includes: a data analysis and decision module system 1 which is bidirectionally connected to the denitration inlet flue gas parameter monitoring module 3, the catalyst interlayer temperature acquisition system 6, the denitration outlet flue gas parameter monitoring module 7 and the nitrous oxide analyzer 8, and continuously transmits the acquired data to the portable computer. The user can check, filter, store and export the flue gas parameters required by the user by operating the data analysis and decision module system 1, and can calculate the maximum value, minimum value, average value, standard deviation and high-order data of the discreteness of each flue gas parameter in the entire flue section, and then form corresponding charts to realize the visualization of the measurement results for on-site analysis and equipment adjustment.

[0024] Specifically: In this embodiment, the denitrification ammonia nitrogen mixing device 5 is arranged in the inlet flue of the denitrification device, specifically: A disc device is installed above the ammonia spray grid of the denitrification ammonia nitrogen mixing device 5, so that when the flue gas and ammonia flow through the denitrification ammonia nitrogen mixing device 5, a variety of vortex streets will be generated on the leeward side of the disc device to enhance the mixing rate of ammonia and flue gas.

[0025] It should be noted that in this embodiment, a denitrification ammonia nitrogen mixing device 5 is arranged at the denitrification inlet to accelerate the mixing of nitrogen oxides and ammonia in the flue gas, alleviate problems such as ammonia escape caused by uneven ammonia injection, improve the utilization rate of the reducing agent, and improve the denitrification effect; specifically, according to the load changes of the unit and the measurement data of the nitrous oxide analyzer 8, the blade posture of the ammonia nitrogen mixing device 5 is adjusted to alleviate ammonia escape caused by uneven ammonia injection and assist in controlling the generation of nitrous oxide.

[0026] In this embodiment, the ratio of nitrogen oxides to ammonia is analyzed in real time by the denitrification inlet flue gas parameter monitoring module 3 and the denitrification outlet flue gas parameter monitoring module 7, and the ammonia injection flow rate is accurately adjusted to further reduce the selectivity of nitrous oxide in the side reaction of the denitrification system, improve the selectivity of nitrogen, and promote the synthesis of nitrogen from the remaining amino groups, imine radicals, nitrogen radicals and nitrogen oxides, that is, to promote the denitrification reaction to proceed in the forward direction.

[0027] This embodiment uses the catalyst interlayer temperature acquisition system 6 to accurately control the denitration reaction temperature, timely avoid the temperature range that is conducive to the generation of nitrous oxide, further reduce the production of greenhouse gas nitrous oxide, and reduce environmental pollution and damage to the atmosphere.

[0028] Example 2 like Figure 2 A method for reducing nitrous oxide emissions from an SCR denitration device is implemented by applying the nitrous oxide emission reduction control system of the SCR denitration device of Example 1, and the method comprises the following steps: S1. Based on the one-machine-one-policy approach, the optimal process control parameters for suppressing N2O generation are determined based on the historical inlet and outlet flue gas parameters of the denitrification device of the unit and the historical operation status of the equipment: ammonia nitrogen ratio of 0.99 and flue gas temperature of 310-360 degrees; S2. Obtaining real-time operation data of the denitrification device, and synchronously executing steps S3 and S4 based on the real-time operation data of the denitrification device; S3. Calculate the actual ammonia nitrogen ratio based on the data obtained in step S2, and determine whether it is greater than 0.99; and further control the ammonia nitrogen ratio based on the result until the ammonia nitrogen ratio = 0.99; S4. Calculate whether the denitration reaction temperature obtained in step S2 is within the optimal range of 310-360 degrees, and control the flue gas temperature based on the calculation result until the denitration reaction temperature is not within 310-360 degrees; S5. Measure N2O at the outlet of the denitrification device; S6. Determine whether the N2O concentration meets the preset requirements: if so, the method is terminated; if not, proceed to step S2; Among them, the loop feedback dynamic adjustment steps: S3-S6 are executed based on the data analysis and decision model system 1. The data analysis and decision model system 1 calculates the material ratio of the denitrification reaction based on the denitrification inlet flue gas parameter monitoring module 3 and the denitrification outlet flue gas parameter monitoring module 7, calculates the ammonia nitrogen molar ratio, and further adjusts the ammonia nitrogen ratio to the target state through the ammonia injection flow adjustment device 4, and controls the nitrous oxide production by optimizing the material ratio. Among them, the target state is a slightly excessive state in actual application. The data analysis and decision model system 1 accurately monitors the denitrification reaction temperature of each layer in the SCR denitrification device based on the catalyst interlayer temperature acquisition system 6, and further adjusts the reaction temperature to below 310 or above 360 ​​in a nearby adjustment manner through the flue gas temperature adjustment device 2, avoiding the temperature range that is conducive to the generation of nitrous oxide, and controlling the nitrous oxide production by dynamically optimizing the denitrification reaction temperature. The data analysis and decision model system 1 realizes the display of nitrous oxide concentration and excessive warning through real-time data communication with the nitrous oxide analyzer 8 installed at the denitrification outlet.

[0029] Specifically: S2. Obtain denitrification device data, including: The denitrification inlet flue gas parameter monitoring module 3 is used to measure the denitrification inlet flue gas flow rate, the denitrification inlet nitrogen oxide concentration and the ammonia injection flow rate in real time; The denitrification outlet flue gas parameter monitoring module 7 is used to measure the denitrification outlet flue gas flow rate and the denitrification outlet nitrogen oxide concentration in real time, and further calculate the ammonia nitrogen molar ratio; The catalyst interlayer temperature acquisition system 6 is used to measure the operating temperature of each catalyst layer in real time, and record historical operating data to accurately control the denitration reaction temperature; The nitrous oxide analyzer 8 is used to measure the N2O concentration at the denitrification outlet in real time, and the control result of the nitrous oxide emission reduction control method of the SCR denitrification device is fed back to improve the adjustment accuracy.

[0030] It also includes: an adaptive iterative update method based on data analysis and decision model system 1, specifically including: The data analysis and decision-making model system 1 receives and stores the data transmitted by the nitrous oxide analyzer 8 to generate a historical concentration data set; Iteratively and accurately optimize the control path of the SCR denitrification device nitrous oxide emission reduction control method based on the historical concentration data set; Based on the historical concentration data set, the preset requirements for N2O concentration at the denitrification outlet are accurately adapted to multiple levels.

[0031] Example 3 Based on Example 2, this example discloses a method for controlling nitrous oxide emission reduction of an SCR denitration device based on material balance adjustment, the method comprising the following steps: S1. Determine the optimal process control parameters for suppressing N2O generation based on the historical inlet and outlet flue gas parameters of the denitrification device of the unit and the historical operation status of the equipment: ammonia nitrogen ratio of 0.99 and flue gas temperature of 310-360 degrees; S2. Obtaining real-time operation data of the denitrification device; S3. Calculate the actual ammonia nitrogen ratio based on the data obtained in step S2, and determine whether it is greater than 0.99; and further control the ammonia nitrogen ratio based on the result until the ammonia nitrogen ratio = 0.99: S5. Measure N2O at the outlet of the denitrification device; S6. Determine whether the N2O concentration meets the preset requirements: if so, the method is terminated; if not, proceed to step S2; The loop feedback dynamic adjustment steps: S3-S6 are executed based on data analysis and decision-making model system.

[0032] Specifically: Step S3 calculates the actual ammonia nitrogen ratio based on the data obtained in step S2, and determines whether it is greater than 0.99; and further controls the ammonia nitrogen ratio based on the result, specifically: The actual ammonia nitrogen ratio is calculated based on the data obtained in step S2, and it is determined whether it is greater than 0.99: If yes, reduce the ammonia spraying amount of the ammonia spraying flow regulating device 4, adjust the blade attitude angle of the denitrification ammonia nitrogen mixing device 5, and execute step 5 after the ammonia nitrogen ratio reaches 0.99; If not, on the basis of monitoring that ammonia escape does not exceed the standard, increase the ammonia spray amount of the ammonia spray flow regulating device 4, adjust the blade attitude angle of the denitrification ammonia nitrogen mixing device 5, until the ammonia nitrogen ratio = 0.99, and then execute step 5.

[0033] Example 4 This embodiment discloses a method for reducing nitrous oxide emissions from an SCR denitration device based on reaction temperature regulation on the basis of embodiment 2. The method comprises the following steps: S1. Determine the optimal process control parameters for suppressing N2O generation based on the historical inlet and outlet flue gas parameters of the denitrification device of the unit and the historical operation status of the equipment: ammonia nitrogen ratio of 0.99 and flue gas temperature of 310-360 degrees; S2. Obtaining real-time operation data of the denitrification device; S4. Calculate whether the denitration reaction temperature obtained in step S2 is within the optimal range of 310-360 degrees, and control the flue gas temperature based on the calculation result until the denitration reaction temperature is not within 310-360 degrees; S5. Measure N2O at the outlet of the denitrification device; S6. Determine whether the N2O concentration meets the preset requirements: if so, the method is terminated; if not, proceed to step S2; The loop feedback dynamic adjustment steps: S3-S6 are executed based on data analysis and decision-making model system.

[0034] Specifically: S4. Calculate whether the denitration reaction temperature obtained in step S3 is within the optimal range of 310-360 degrees, and control the flue gas temperature based on the calculation result, specifically: If the flue gas temperature is within the range of 310-360 degrees, the flue gas temperature regulating device 2 is used to regulate the flue gas temperature of the denitration device until the denitration reaction temperature is lower than 310 degrees or higher than 360 degrees, and then step 5 is performed; If the denitration reaction temperature is lower than 310 degrees or higher than 360 degrees, proceed to step 5.

[0035] Obviously, the above embodiments are merely examples for the purpose of clear explanation, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection of the invention.

Claims

1. A nitrous oxide emission reduction control system for an SCR denitration device, characterized in that: include: A flue gas temperature regulating device (2) provided at the inlet of the control system; A denitration inlet flue gas parameter monitoring module (3) arranged at the inlet of the denitration device and a denitration outlet flue gas parameter monitoring module (7) arranged at the outlet of the denitration device; and a pipe connection of an ammonia injection flow regulating device (4), a denitrification ammonia nitrogen mixing device (5), a catalyst interlayer temperature acquisition system (6) and a denitrification outlet flue gas parameter monitoring module (7) which are sequentially arranged in the denitrification device according to the flue gas output direction; The control system also includes: a data analysis and decision-making model system (1) connected to the denitration inlet flue gas parameter monitoring module (3), the catalyst interlayer temperature acquisition system (6), the denitration outlet flue gas parameter monitoring module (7) and the nitrous oxide analyzer (8) by two-way signals.

2. The SCR denitration device nitrous oxide emission reduction control system according to claim 1, characterized in that: The denitrification ammonia nitrogen mixing device (5) is arranged in the inlet flue of the denitrification device, specifically: A disc device is installed above the ammonia spray grid of the denitrification ammonia nitrogen mixing device (5), so that when the flue gas and ammonia flow through the denitrification ammonia nitrogen mixing device (5), a variety of vortex streets are generated on the leeward side of the disc device, thereby enhancing the mixing rate of ammonia and flue gas.

3. A method for reducing nitrous oxide emissions from an SCR denitration device, characterized in that: The SCR denitration device nitrous oxide emission reduction control system according to claim 2 is used to implement the method, which comprises the following steps: S1. Determine the optimal process control parameters for suppressing N2O generation based on the historical inlet and outlet flue gas parameters of the denitrification device of the unit and the historical operation status of the equipment: ammonia nitrogen ratio of 0.99 and flue gas temperature of 310-360 degrees; S2. Obtaining real-time operation data of the denitrification device, and synchronously executing steps S3 and S4 based on the real-time operation data of the denitrification device; S3. Calculate the actual ammonia nitrogen ratio based on the data obtained in step S2, and determine whether it is greater than 0.99; and further control the ammonia nitrogen ratio based on the result until the ammonia nitrogen ratio = 0.99; S4. Calculate whether the denitration reaction temperature obtained in step S2 is within the optimal range of 310-360 degrees, and control the flue gas temperature based on the calculation result until the denitration reaction temperature is not within 310-360 degrees; S5. Measure N2O at the outlet of the denitrification device; S6. Determine whether the N2O concentration meets the preset requirements: if so, the method is terminated; if not, proceed to step S2; The loop feedback dynamic adjustment steps S3-S6 are executed based on the data analysis and decision model system (1).

4. The SCR denitration device nitrous oxide emission reduction control system according to claim 3, characterized in that: Step S3 calculates the actual ammonia nitrogen ratio based on the data obtained in step S2, and determines whether it is greater than 0.99; and further controls the ammonia nitrogen ratio based on the result, specifically: The actual ammonia nitrogen ratio is calculated based on the data obtained in step S2, and it is determined whether it is greater than 0.99: If yes, then reduce the amount of ammonia sprayed by the ammonia spray flow rate regulating device (4), adjust the blade attitude angle of the denitrification ammonia nitrogen mixing device (5), and then execute step 5 until the ammonia nitrogen ratio is 0.99; If not, on the basis of monitoring that ammonia escape does not exceed the standard, increase the ammonia spraying amount of the ammonia spraying flow regulating device (4), and adjust the blade attitude angle of the denitrification ammonia nitrogen mixing device (5) until the ammonia nitrogen ratio is 0.99, and then execute step 5.

5. The nitrous oxide emission reduction control system of the SCR denitration device according to claim 3, characterized in that: S4. Calculate whether the denitration reaction temperature obtained in step S3 is within the optimal range of 310-360 degrees, and control the flue gas temperature based on the calculation result, specifically: If the flue gas temperature is within the range of 310-360 degrees, the flue gas temperature regulating device (2) is used to regulate the flue gas temperature of the denitration device until the denitration reaction temperature is lower than 310 degrees or higher than 360 degrees, and then step 5 is performed; If the denitration reaction temperature is lower than 310 degrees or higher than 360 degrees, proceed to step 5.

6. The method for reducing nitrous oxide emissions from an SCR denitration device according to claim 3, characterized in that: S2. Obtain denitrification device data, including: The denitrification inlet flue gas parameter monitoring module (3) is used to measure the denitrification inlet flue gas flow rate, the denitrification inlet nitrogen oxide concentration and the ammonia injection flow rate in real time; The denitrification outlet flue gas parameter monitoring module (7) is used to measure the denitrification outlet flue gas flow rate and the denitrification outlet nitrogen oxide concentration in real time, and further calculate the ammonia nitrogen molar ratio; Using the catalyst interlayer temperature acquisition system (6) to measure the operating temperature of each catalyst layer in real time and record historical operating data; The nitrous oxide analyzer (8) is used to measure the N2O concentration at the denitrification outlet in real time, and the control result of the nitrous oxide emission reduction control method of the SCR denitrification device is fed back.

7. The method for reducing nitrous oxide emissions from an SCR denitration device according to claim 3, characterized in that: Also includes: The adaptive iterative updating method based on the data analysis and decision model system (1) specifically includes: The data analysis and decision-making model system (1) receives and stores the data transmitted by the nitrous oxide analyzer (8) to generate a historical concentration data set; Iteratively and accurately optimize the control path of the SCR denitrification device nitrous oxide emission reduction control method based on the historical concentration data set; Based on the historical concentration data set, the preset requirements for N2O concentration at the denitrification outlet are accurately adapted to multiple levels.

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