Multidimensional coupling method for ammonia nitrogen matching in denitrification and ammonia nitrogen matching denitrification system

Abstract

This invention relates to a multi-dimensional coupled ammonia nitrogen matching method and ammonia nitrogen matching denitrification system, specifically including the following steps: setting up several ammonia injection zones at the denitrification inlet and setting up several measurement zones corresponding to the ammonia injection zones at the denitrification outlet; calculating the basic ammonia injection rate, the advance response ammonia injection rate, and the feedback ammonia injection rate based on system parameters, and summing them to obtain the total ammonia injection rate; the system parameters include flue gas volume, inlet NO... X Concentration, export NO X Preset concentration, outlet NO X Measure concentration and inlet NO within a preset time. X Concentration change value, system conversion coefficient, system response coefficient, and system feedback coefficient; zonal leveling, including calculating NO in each of the aforementioned measurement zones. X The ratio of concentrations is used to determine the total ammonia injection amount, which is then injected into the corresponding ammonia injection zone based on this ratio. This enables precise ammonia injection into the denitrification system, reducing NO levels. X It has the advantage of avoiding energy waste while emitting emissions.

Description

Technical Field

[0001] This invention relates to the technical field of environmental protection in coal-fired power plants, and in particular to a multi-dimensional coupled method for matching ammonia nitrogen in denitrification and an ammonia nitrogen matching denitrification system. Background Technology

[0002] SCR flue gas denitrification technology is used in coal-fired boilers. The mainstream technology for ultra-low emissions involves injecting ammonia into the flue gas duct to mix the ammonia with... A chemical reaction occurs, thereby reducing the output of the denitrification system. Content, in order to reduce The purpose of emissions.

[0003] In existing denitrification systems, on the one hand, factors such as instrument measurement, data transmission, and the chemical reactions within the denitrification system itself can lead to a certain lag in the control of system concentration. On the other hand, under conditions of deep peak shaving by the unit, the drastic fluctuations in load further amplify the negative impact of the non-uniformity of the flow field in the denitrification system. This can easily lead to problems such as poor uniformity of the velocity field throughout the entire process and issues with concentration field control. Furthermore, it can easily lead to a mismatch between nitrogen and ammonia in the denitrification system, making it impossible to effectively reduce the nitrogen content at the denitrification outlet. This reduces emissions and minimizes ammonia energy waste to ensure efficient and economical operation of the unit.

[0004] Therefore, a multi-dimensional coupled ammonia nitrogen matching method and ammonia nitrogen matching denitrification system are provided to achieve precise ammonia injection in the denitrification system and reduce nitrogen content. Avoiding energy waste while emitting pollutants is a problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to overcome the defects in the prior art, thereby providing a multi-dimensional coupled denitrification ammonia nitrogen matching method and ammonia nitrogen matching denitrification system.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] A multidimensional coupled method for matching ammonia nitrogen in denitrification specifically includes the following steps:

[0008] Several ammonia injection zones are set at the denitrification inlet, and several measurement zones are set at the denitrification outlet corresponding to the ammonia injection zones;

[0009] The base ammonia injection rate, the advance response ammonia injection rate, and the feedback ammonia injection rate are calculated based on system parameters and summed to obtain the total ammonia injection rate. The system parameters include flue gas volume, inlet... Concentration, outlet Preset concentration, outlet Measure concentration, inlet within preset time Concentration change, system conversion coefficient, system response coefficient, and system feedback coefficient;

[0010] Zonal leveling includes calculating the values ​​for each of the aforementioned measurement zones. The ratio of concentrations is used to determine the total amount of ammonia to be injected into the corresponding ammonia injection zone.

[0011] Preferably, the calculation of the basic ammonia injection rate, the advance response ammonia injection rate, and the feedback ammonia injection rate based on system parameters specifically includes the following steps:

[0012] The total flue gas volume is calculated using the following formula:

[0013] or ;

[0014] The basic ammonia injection rate is calculated using the following formula:

[0015] ;

[0016] The formula for calculating the ammonia injection amount for early response is as follows:

[0017] ;

[0018] The formula for calculating the feedback ammonia injection rate is as follows:

[0019] ;

[0020] Where Q is the total flue gas volume. Standard state, dry basis, 6% ; For the total online coal quantity, ; The conversion coefficient for bituminous coal; Total online air volume ; The wind-smoke conversion coefficient; Based on the basic ammonia injection rate, ; For the entrance concentration, Standard state, dry basis, 6% ; For export Preset concentration, Standard state, dry basis, 6% ; These are system conversion coefficients, with values ​​ranging from 4300 to 4700; In order to respond in advance to the amount of ammonia injected, ; Entry within the preset time Concentration change value; The system response coefficient has a value range of 0.85 to 1.15. For export Measure concentration, Standard state, dry basis, 6% ; This is the system feedback coefficient, with a value range of 0.85 to 1.15.

[0021] Preferably, the step of setting up several ammonia injection zones at the denitrification inlet and setting up several measurement zones corresponding to the ammonia injection zones at the denitrification outlet specifically includes the following steps:

[0022] The denitrification inlet is divided into several ammonia injection zones, each with a control area of ​​M1 and a cross-sectional area of ​​M2. The ratio of M2 to M1 is 3 ≤ M2 / M1 ≤ 8.

[0023] The denitrification outlet is divided into several measurement zones, each measurement zone has a control area of ​​M3, and the denitrification outlet has a cross-sectional area of ​​M4. The ratio of M4 to M3 is 3≦M3 / M4≦8.

[0024] Preferably, the partition leveling further includes the following steps:

[0025] Several sampling points are selected within each of the measurement zones;

[0026] The sampling point is determined within its corresponding measurement zone based on the numerical simulation results of the ammonia nitrogen molar ratio.

[0027] The measurement zones are obtained sequentially through the sampling points. concentration.

[0028] Preferably, determining the preset location of the sampling point within its corresponding measurement zone based on the numerical simulation results of the ammonia-nitrogen molar ratio specifically includes the following steps:

[0029] Comparison of simulations at multiple sampling points at the denitrification outlet Concentration data and actual measurements Concentration data, obtain comparison results;

[0030] Based on the comparison results, the generator unit was leveled.

[0031] Adjust the ammonia injection rate of the ammonia injection zone according to the preset gradient;

[0032] The ammonia injection rate was compared with the measured values ​​at the sampling points. If the concentration data are positively correlated, then the sampling point is located at the preset position.

[0033] Preferably, the method further includes the installation of a zone measurement device, specifically comprising the following steps:

[0034] A zone measurement device is installed on the inclined flue on side A or B of the denitrification outlet, and the zone measurement device includes a sampling tube.

[0035] The sampling tube opening is located at the preset position.

[0036] Preferably, it also includes deviation leveling, specifically comprising the following steps:

[0037] Set each of the aforementioned measurement zones The ideal value of concentration;

[0038] Set each of the aforementioned measurement zones Concentration deviation range;

[0039] Sequentially obtain the measurements of each measurement zone. Measured concentration value;

[0040] Calculate the difference between the ideal value and the measured value;

[0041] Determine each measurement zone If the concentration difference is within the deviation range, then a preset amount of ammonia is injected into the corresponding ammonia injection zone.

[0042] Preferably, it further includes cross-mixing ammonia and the flue gas to be denitrified downstream of each of the ammonia injection zones.

[0043] Preferably, it also includes mixed sampling, specifically including the following steps: after the system returns to steady state, acquiring the values ​​of each measurement zone. And mix.

[0044] An ammonia nitrogen matching denitrification system based on the above-mentioned multidimensional coupling ammonia nitrogen matching method includes,

[0045] A zoned ammonia injection device has several ammonia injection zones, which are located at the denitrification inlet;

[0046] A zoned measurement device has several measurement zones, which are located at the denitrification outlet;

[0047] The total ammonia injection calculation module is used to calculate the base ammonia injection rate, the advance response ammonia injection rate, and the feedback ammonia injection rate based on system parameters, and sum them to obtain the total ammonia injection rate; the system parameters include flue gas volume, inlet... Concentration, outlet Preset concentration, outlet Measure concentration, inlet within preset time Concentration change, system conversion coefficient, system response coefficient, and system feedback coefficient;

[0048] The zonal leveling module includes a ratio calculation unit and a control unit; the ratio calculation unit is used to calculate the ratios for each of the measurement zones. The ratio of concentrations; the control unit is used to control the zoned ammonia injection device to inject ammonia into the corresponding ammonia injection zone according to the ratio.

[0049] Preferably, the zone measurement device is installed on the inclined flue on the A / B side of the denitrification outlet;

[0050] The partition measurement device includes sampling tubes set according to the measurement partition, and each sampling tube has a plurality of sampling tube ports;

[0051] The location of the sampling port was determined based on the numerical simulation results of the ammonia-nitrogen molar ratio.

[0052] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0053] The above-mentioned technical solution provides a multi-dimensional coupled ammonia nitrogen matching method for denitrification, which uses flue gas volume and inlet temperature as parameters. Concentration, outlet Preset concentration, outlet Measure concentration, inlet within preset time By using system parameters such as concentration change, system conversion coefficient, system response coefficient, and system feedback coefficient, the base ammonia injection rate, the advance response ammonia injection rate, and the feedback ammonia injection rate can be calculated, thereby obtaining the accurate total ammonia injection rate. Then, the ammonia injection rate for each of the aforementioned measurement zones can be calculated. The ratio of concentrations is used to determine the total ammonia injection amount, which is then injected into the corresponding ammonia injection zone. This reduces the impact of errors caused by system lag on the total ammonia injection amount, ensuring accuracy. Furthermore, the interaction between total ammonia injection control and zone leveling control ensures accurate ammonia injection control, further reducing operating costs and guaranteeing efficient and economical unit operation while ensuring the denitrification system meets emission standards. Correspondingly, the ammonia-nitrogen matching denitrification system based on a multi-dimensional coupling method provided in the above technical solution, through the inclusion of zone ammonia injection devices, zone measurement devices, total ammonia injection calculation modules, and zone leveling modules, achieves precise control of the total ammonia injection amount, further reducing operating costs and ensuring efficient and economical unit operation while guaranteeing the denitrification system meets emission standards. Attached Figure Description

[0054] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0055] Figure 1 A schematic diagram illustrating one example of the method provided by the present invention.

[0056] Figure 2 for Figure 1 A schematic diagram of one example of step S2.

[0057] Figure 3 for Figure 1 A schematic diagram of one example of step S3.

[0058] Figure 4 for Figure 1 A schematic diagram of one example of step S5 in the diagram.

[0059] Figure 5 A schematic diagram of one example of the system provided by the present invention.

[0060] Explanation of reference numerals in the attached figures:

[0061] 1. Zoned ammonia injection device; 2. Zoned measurement device; 21. Sampling tube; 3. Layered cross mixer; 4. Baffle plate; 5. Rectifier; 6. Catalyst assembly; 101. Inlet flue; 102. Outlet flue. Detailed Implementation

[0062] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0063] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0064] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0065] See Figures 1 to 4 This invention provides a multidimensional coupled method for matching ammonia nitrogen in denitrification, specifically including the following steps:

[0066] S1: Set up several ammonia injection zones at the denitrification inlet and set up several measurement zones at the denitrification outlet corresponding to the ammonia injection zones.

[0067] S2: Calculate the base ammonia injection rate, the advance response ammonia injection rate, and the feedback ammonia injection rate based on system parameters, and sum them to obtain the total ammonia injection rate. System parameters include flue gas volume, inlet... Concentration, outlet Preset concentration, outlet Measure concentration, inlet within preset time Concentration change value, system conversion coefficient, system response coefficient, and system feedback coefficient.

[0068] S3: Zonal leveling, including calculating the leveling of each measurement zone. The ratio of concentrations is used to determine the total amount of ammonia to be injected into the corresponding ammonia injection zone.

[0069] S4: Mixed sampling. This specifically includes the following steps: After the system returns to steady state, obtain the data for each measurement zone. And mix.

[0070] S5: Deviation leveling, used according to measurement zones. Concentration deviation is dynamically adjusted to control the amount of ammonia injected into each ammonia injection zone.

[0071] Specifically, through the amount of flue gas and the inlet Concentration, outlet Preset concentration, outlet Measure concentration, inlet within preset time By using system parameters such as concentration change, system conversion coefficient, system response coefficient, and system feedback coefficient, the base ammonia injection rate, the advance response ammonia injection rate, and the feedback ammonia injection rate can be calculated, thereby obtaining the accurate total ammonia injection rate. Then, the ammonia injection rate for each of the aforementioned measurement zones can be calculated. The ratio of concentrations is used to determine the total ammonia injection amount, which is then injected into the corresponding ammonia injection zone. On the one hand, this can reduce the impact of errors caused by system lag on the total ammonia injection amount to a certain extent, ensuring the accuracy of the total ammonia injection amount. On the other hand, through the interaction between total ammonia injection amount control and zone leveling control, the accuracy of ammonia injection control is ensured. This further reduces operating costs and ensures efficient and economical operation of the unit while ensuring that the denitrification system meets emission standards.

[0072] Specifically, step S2 includes:

[0073] S2.1: Calculate the total flue gas volume.

[0074] Specifically, the total flue gas volume can be accurately calculated based on the system's coal feed rate, total air volume, primary air volume, main steam volume, and system conversion coefficient. In this embodiment, either Formula 1 or Formula 2 can be used for calculation.

[0075] Formula 1: ;

[0076] Formula 2: .

[0077] Where Q is the total flue gas volume. Standard state, dry basis, 6% ; For the total online coal quantity, ; The conversion coefficient for bituminous coal; Total online air volume ; This is the wind-smoke conversion coefficient.

[0078] It is worth noting that, This is the coefficient for converting total coal volume to flue gas volume. It is dimensionless and can be calculated using (total air volume + total coal volume) × 1000 ÷ total coal volume ÷ 1.34 ÷ 2. Correspondingly, It is the coefficient for converting total air volume to flue gas volume. It is dimensionless and can be calculated as (total air volume + total coal volume) × 1000 ÷ total air volume ÷ 1.34 ÷ 2.

[0079] S2.2: Calculate the basic ammonia injection rate.

[0080] Specifically, in this embodiment, Formula 3 can be used for calculation.

[0081] Formula 3: .

[0082] in, Based on the basic ammonia injection rate, ; For the entrance concentration, Standard state, dry basis, 6% ; For export Preset concentration, Standard state, dry basis, 6% ; For system conversion coefficients, The value range is 4300 to 4700.

[0083] S2.3: Calculate the ammonia injection rate for early response. Since the denitrification inlet is measured by instruments... The concentration has a certain lag; therefore, the concentration is measured by the denitrification inlet instrument. concentration, Standard state, dry basis, 6% The calculated ammonia injection quantity has a certain lag. Therefore, calculating the ammonia injection quantity in advance can improve the accuracy of the total ammonia injection quantity calculation, thereby improving the control precision of the system and ensuring the accuracy of ammonia injection control.

[0084] Specifically, in this embodiment, Formula 4 can be used for calculation.

[0085] Formula 4: ;

[0086] in, In order to respond in advance to the amount of ammonia injected, ; Entry within the preset time Concentration change value; The system response coefficient has a value range of 0.85 to 1.15.

[0087] S2.4: Calculate the amount of ammonia injected in feedback.

[0088] Specifically, in this embodiment, calculations can be performed using Formula 5.

[0089] Formula 5: ;

[0090] in, For export Measure concentration, Standard state, dry basis, 6% ; This is the system feedback coefficient, with a value range of 0.85 to 1.15.

[0091] S2.5: Calculate the total ammonia injection amount.

[0092] Specifically, in this embodiment, calculations can be performed using Formula Six.

[0093] Formula Six: .

[0094] Where S is the total ammonia injection amount, .

[0095] It is known that since the ammonia injected by the ammonia injection unit is diluted, and the ammonia-air mixing ratio after dilution does not exceed 5%, the more measurement zones and ammonia injection zones there are, the smaller the control area for ammonia injection becomes, and the smaller the amount of ammonia injection adjustment, which can easily lead to an insignificant ammonia injection control effect. Furthermore, the control valves corresponding to the measurement zones and ammonia injection zones have a throttling effect on the dilution airflow; too many measurement zones and ammonia injection zones can lead to excessively low dilution airflow and an increased ammonia-nitrogen ratio. Moreover, an excessive number of ammonia injection zones and measurement zones increases the technical difficulty of implementation, raises the cost of unit modification, and may also cause unit side effects such as blockages. Conversely, too few measurement zones and ammonia injection zones cannot meet the goal of refined and intelligent unit control. Therefore, in this embodiment, the number of measurement zones and ammonia injection zones is set according to the unit's corresponding design parameters.

[0096] Specifically, in this embodiment, step S1 includes:

[0097] The denitrification inlet is divided into several ammonia injection zones, each with a control area of ​​M1 and a cross-sectional area of ​​M2. The ratio of M2 to M1 is 3≦M2 / M1≦8.

[0098] Several measurement zones are divided at the denitrification outlet. The control area of ​​each measurement zone is M3, and the cross-sectional area of ​​the denitrification outlet is M4. The ratio of M4 to M3 is 3≦M4 / M3≦8.

[0099] Preferably, the number of ammonia injection zones at the denitrification inlet can be kept consistent with the number of measurement zones at the denitrification outlet.

[0100] Furthermore, in this embodiment, step S3 (regional leveling) specifically includes the following steps:

[0101] S3.1: Select several sampling points within each measurement zone;

[0102] S3.2: Determine the preset location of the sampling point within its corresponding measurement zone based on the numerical simulation results of the ammonia nitrogen molar ratio;

[0103] S3.3: Obtain the data for each measurement zone sequentially through sampling points. concentration.

[0104] S3.4: The heated boiler-side cooling primary air is delivered to the sampling tube of the zone measurement device.

[0105] Furthermore, in this embodiment, S3.2 specifically includes the following steps:

[0106] S3.2.1: Simulation comparing multiple sampling points at the denitrification outlet Concentration data and actual measurements Concentration data, obtain comparison results;

[0107] S3.2.2: Based on the comparison results, adjust the unit; it is worth noting that the unit adjustment here refers to adjusting the ammonia injection rate to ensure the denitrification outlet... The concentration meets the standard.

[0108] S3.2.3: Adjust the ammonia injection rate of the ammonia injection zone according to the preset gradient.

[0109] S3.2.4: Determine the difference between the ammonia injection rate and the measured values ​​at the sampling points. If the concentration data are positively correlated, the sampling point is located at the preset position.

[0110] In detail, in this embodiment, the ammonia injection amount in each area can be increased by 25%, 50%, 75%, and 100% in sequence to verify the change in concentration value at the corresponding sampling point of the denitrification outlet section. When the ammonia injection amount in each area increases, the corresponding measurement point value also shows a significant positive correlation, indicating that each ammonia injection zone corresponds to the outlet measurement point, and this position can be considered as the preset position.

[0111] Furthermore, this method also includes the installation of a zone measurement device, specifically including the following steps: installing a zone measurement device on the inclined flue on the A or B side of the denitrification outlet, the zone measurement device including a sampling tube; the inlet of the sampling tube is set at a preset position.

[0112] See Figure 1 and Figure 4 In this embodiment, step S5 specifically includes the following steps:

[0113] S5.1: Configure each measurement zone The ideal value of concentration;

[0114] S5.2: Set the measurement zones Concentration deviation range;

[0115] S5.3: Use a zone measurement device to sequentially obtain the values ​​of each measurement zone. Measured concentration value;

[0116] S5.4: Calculate the difference between the ideal value and the measured value;

[0117] S5.5: Determine the measurement zones If the concentration difference is within the deviation range, then inject the preset amount of ammonia into the corresponding ammonia injection zone.

[0118] To improve mixing efficiency and address the issue of poor uniformity of the velocity field throughout the denitrification system, this embodiment further includes cross-mixing of ammonia and the flue gas to be denitrified downstream of each ammonia injection zone. (Not shown in the figure.)

[0119] Specifically, a layered cross-mixer can be installed in the flue within a range of 0.5 to 5 m downstream of the ammonia injection device. The flue has a rectangular cross-section. Under the action of the layered cross-mixer, the flue gas is layered and cross-mixed in the same direction as the short side of the rectangular cross-section. When the rectangular cross-section is divided into N ammonia injection zones and measurement zones along the long side, it is divided into at least 2N cross-units along the long side of the rectangular cross-section.

[0120] See Figure 5 This embodiment also provides a denitrification ammonia nitrogen matching system based on the above-mentioned multidimensional coupling denitrification ammonia nitrogen matching method, including a zoned ammonia injection device 1, a zoned measurement device 2, a total ammonia injection quantity calculation module, and a zoned leveling module. The zoned ammonia injection device 1 has several ammonia injection zones, which are located at the denitrification inlet. The zoned measurement device 2 has several measurement zones, which are located at the denitrification outlet. The total ammonia injection quantity calculation module is used to calculate the basic ammonia injection quantity, the advance response ammonia injection quantity, and the feedback ammonia injection quantity according to system parameters, and sum them to obtain the total ammonia injection quantity; wherein, the system parameters include flue gas volume, inlet... Concentration, outlet Preset concentration, outlet Measure concentration, inlet within preset time Concentration change value, system conversion coefficient, system response coefficient, and system feedback coefficient.

[0121] Specifically, the zoned ammonia injection device 1 is installed at the inlet flue 101 (i.e., the denitrification inlet). The zoned ammonia injection device 1 includes an ammonia injection grid 11, which forms several ammonia injection zones.

[0122] The zone leveling module includes a ratio calculation unit and a control unit; the ratio calculation unit is used to calculate the ratio of each measurement zone. The concentration ratio; the control unit is used to control the ammonia injection device to inject ammonia into the corresponding ammonia injection zone according to the ratio. (Not shown in the diagram.)

[0123] It is worth noting that, in this embodiment, in order to facilitate operation by the operator, the total ammonia injection calculation module and the zonal leveling module are both integrated into the computer, and data interaction and command signal transmission are realized through the computer with the zonal ammonia injection device 1 and the zonal measuring device 2.

[0124] See Figure 5The zone measurement device 2 is installed at the outlet flue 102 (i.e., the denitrification outlet). Specifically, the zone measurement device 2 is installed on the inclined flue on the A or B side of the denitrification outlet. The zone measurement device 2 includes sampling tubes 21 set for the corresponding measurement zone. Each sampling tube 21 has several sampling ports. The position of the sampling ports in the measurement zone is determined according to the numerical simulation results of the ammonia-nitrogen molar ratio.

[0125] See Figure 5 The system also includes a stratified cross mixer 3, a guide plate 4, a rectifier 5, and a catalyst assembly 6. The stratified cross mixer 3 is used to equalize the flue gas velocity field. The guide plate 4 is set in an arc shape, which can be set according to the required flow direction of the flue gas, thereby guiding the flue gas to the catalyst assembly 6. The catalyst assembly 6 is used to react with the flue gas to undergo a denitrification reaction.

[0126] It can be seen that, along the upward flow of flue gas, the ammonia injection grid 11, the stratified cross-mixer 3, the guide plate 4, the rectifier 5, the catalyst assembly 6, and the zone measurement device 2 are arranged in sequence. That is, the flue gas enters from the inlet flue 101, flows through the ammonia injection grid 11, the stratified cross-mixer 3, the guide plate 4, the rectifier 5, the catalyst assembly 6, and the zone measurement device 2 in sequence, and is discharged from the outlet flue 102.

[0127] The above embodiments are merely preferred embodiments of the present invention and should not be construed as limiting the scope of protection of the present invention. Any non-substantial changes and substitutions made by those skilled in the art based on the present invention shall fall within the scope of protection claimed by the present invention.

Claims

1. A multidimensional coupled method for matching ammonia nitrogen in denitrification, characterized in that, Specifically, the following steps are included: Several ammonia injection zones are set at the denitrification inlet, and several measurement zones are set at the denitrification outlet corresponding to the ammonia injection zones; The basic ammonia injection rate, the advance response ammonia injection rate, and the feedback ammonia injection rate are calculated based on the system parameters, and then summed to obtain the total ammonia injection rate. The system parameters include flue gas volume and inlet gas volume. Concentration, outlet Preset concentration, outlet Measure concentration, inlet within preset time Concentration change, system conversion coefficient, system response coefficient, and system feedback coefficient; Zonal leveling includes calculating the values ​​for each of the aforementioned measurement zones. The ratio of concentrations, and the total amount of ammonia injected is injected into the corresponding ammonia injection zone according to the ratio; The calculation of the basic ammonia injection rate, the advance response ammonia injection rate, and the feedback ammonia injection rate based on system parameters specifically includes the following steps: The total flue gas volume is calculated using the following formula: or ; The basic ammonia injection rate is calculated using the following formula: ； The formula for calculating the ammonia injection amount for early response is as follows: ； The formula for calculating the feedback ammonia injection rate is as follows: ； Where Q is the total flue gas volume. Standard state, dry basis, 6% ; For the total online coal quantity, ; The conversion coefficient for bituminous coal; Total online air volume ; The wind-smoke conversion coefficient; Based on the basic ammonia injection rate, ; For the entrance concentration, Standard state, dry basis, 6% ; For export Preset concentration Standard state, dry basis, 6% ; These are system conversion coefficients, with values ​​ranging from 4300 to 4700; In order to respond in advance to the amount of ammonia injected, ; Entry within the preset time Concentration change value; The system response coefficient has a value range of 0.85 to 1.

15. For export Measure concentration, Standard state, dry basis, 6% ; This is the system feedback coefficient, with a value range of 0.85 to 1.

15.

2. The multidimensional coupling method for matching ammonia nitrogen in denitrification according to claim 1, characterized in that, The method of setting up several ammonia injection zones at the denitrification inlet and setting up several measurement zones corresponding to the ammonia injection zones at the denitrification outlet specifically includes the following steps: The denitrification inlet is divided into several ammonia injection zones, each with a control area of ​​M1 and a cross-sectional area of ​​M2. The ratio of M2 to M1 is 3 ≤ M2 / M1 ≤ 8. The denitrification outlet is divided into several measurement zones, each measurement zone has a control area of ​​M3, and the denitrification outlet has a cross-sectional area of ​​M4. The ratio of M4 to M3 is 3≦M4 / M3≦8.

3. The multidimensional coupling method for matching ammonia nitrogen in denitrification according to claim 2, characterized in that, The partition leveling also includes the following steps: Several sampling points are selected within each of the measurement zones; The sampling point is determined within its corresponding measurement zone based on the numerical simulation results of the ammonia nitrogen molar ratio. The measurement zones are obtained sequentially through the sampling points. concentration.

4. The multidimensional coupling method for matching ammonia nitrogen in denitrification according to claim 3, characterized in that, Determining the preset location of the sampling point within its corresponding measurement zone based on the numerical simulation results of the ammonia-nitrogen molar ratio specifically includes the following steps: Comparison of simulations at multiple sampling points at the denitrification outlet Concentration data and actual measurements Concentration data, obtain comparison results; Based on the comparison results, the generator unit was leveled. Adjust the ammonia injection rate of the ammonia injection zone according to the preset gradient; The ammonia injection rate was compared with the measured values ​​at the sampling points. If the concentration data are positively correlated, then the sampling point is located at the preset position.

5. The multidimensional coupled ammonia nitrogen matching method for denitrification according to claim 3 or 4 further includes the installation of a zone measurement device, specifically comprising the following steps: A zone measurement device is installed on the inclined flue on side A or B of the denitrification outlet, and the zone measurement device includes a sampling tube. The sampling tube opening is located at the preset position.

6. The multidimensional coupling method for matching ammonia nitrogen in denitrification according to claim 1, characterized in that, It also includes deviation balancing, which specifically includes the following steps: Set each of the aforementioned measurement zones The ideal value of concentration; Set each of the aforementioned measurement zones Concentration deviation range; Sequentially obtain the measurements of each measurement zone. Measured concentration value; Calculate the difference between the ideal value and the measured value; Determine each measurement zone If the concentration difference is within the deviation range, then a preset amount of ammonia is injected into the corresponding ammonia injection zone.

7. The multidimensional coupling method for matching ammonia nitrogen in denitrification according to claim 1, characterized in that, It also includes the cross-mixing of ammonia and flue gas to be denitrified downstream of each of the ammonia injection zones.

8. The multidimensional coupling method for matching ammonia nitrogen in denitrification according to claim 1, characterized in that, It also includes mixed sampling, specifically comprising the following steps: after the system returns to steady state, acquiring the data from each measurement partition. And mix.

9. An ammonia nitrogen matching denitrification system based on the multidimensional coupling ammonia nitrogen matching method for denitrification according to any one of claims 1 to 8, characterized in that, include, A zoned ammonia injection device has several ammonia injection zones, which are located at the denitrification inlet; A zoned measurement device has several measurement zones, which are located at the denitrification outlet; The total ammonia injection calculation module is used to calculate the basic ammonia injection quantity, the advance response ammonia injection quantity, and the feedback ammonia injection quantity based on system parameters, and sum them up to obtain the total ammonia injection quantity. The system parameters include flue gas volume and inlet gas volume. Concentration, outlet Preset concentration, outlet Measure concentration, inlet within preset time Concentration change, system conversion coefficient, system response coefficient, and system feedback coefficient; The zonal leveling module includes a ratio calculation unit and a control unit; the ratio calculation unit is used to calculate the ratios for each of the measurement zones. The ratio of concentrations; the control unit is used to control the zoned ammonia injection device to inject ammonia into the corresponding ammonia injection zone according to the ratio.

10. The ammonia nitrogen matching denitrification system according to claim 9, characterized in that, The zoning measurement device is installed on the inclined flue on the A / B side of the denitrification outlet; The partition measurement device includes sampling tubes set according to the measurement partition, and each sampling tube has a plurality of sampling tube ports; The location of the sampling port was determined based on the numerical simulation results of the ammonia-nitrogen molar ratio.

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