Multi-dimensional coupled denitration ammonia nitrogen matching method and ammonia nitrogen matching denitration system

Abstract

The invention relates to a multi-dimensional coupled denitration ammonia nitrogen matching method and an ammonia nitrogen matching denitration system, and the method specifically comprises the following steps: arranging a plurality of ammonia spraying subareas at a denitration inlet, and arranging a plurality of measurement subareas corresponding to the ammonia spraying subareas at a denitration outlet; calculating a basic ammonia spraying amount, an advanced response ammonia spraying amount and a feedback ammonia spraying amount according to system parameters, and summing to obtain a total ammonia spraying amount; the system parameters comprise a flue gas amount, an inlet NOX concentration, an outlet NOX preset concentration, an outlet NOX measured concentration, an inlet NOX concentration change value within preset time, a system conversion coefficient, a system response coefficient and a system feedback coefficient; and zone leveling is conducted, specifically, the ratio of the NOX concentration of each measurement zone is calculated, the total ammonia spraying amount is sprayed to the corresponding ammonia spraying zone according to the ratio, and the method has the advantages that accurate ammonia spraying of the denitration system is achieved, NOX emission is reduced, and meanwhile energy waste is avoided.

Description

Technical Field

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

[0002] SCR flue gas denitrification technology is a new technology for coal-fired boiler NO X The mainstream technology of ultra-low emission is to spray ammonia into the flue to make ammonia and NO X Chemical reaction occurs, thereby reducing the NO at the denitrification outlet X content, in order to reduce NO X Purpose of emission.

[0003] In the existing denitrification system, on the one hand, due to the influence of factors such as instrument measurement, data transmission and the chemical reaction of the denitrification system itself, it is easy to cause a certain lag in the regulation of the system concentration production. On the other hand, under the situation of deep peak regulation of the unit, the drastic fluctuation of the load will further amplify the negative impact of the non-uniformity of the flow field of the denitrification system, which will easily lead to the problem of poor uniformity of the velocity field in the whole process of the denitrification system and the problem after the concentration field is regulated, which will further lead to the mismatch of nitrogen and ammonia in the denitrification system and fail to effectively reduce the NO at the denitrification outlet. X emissions, and reduce ammonia energy waste to ensure efficient and economical operation of the unit.

[0004] Therefore, a multi-dimensional coupled denitrification ammonia nitrogen matching method and an ammonia nitrogen matching denitrification system are provided to achieve precise ammonia injection in the denitrification system and reduce NO X Avoiding energy waste while discharging is an urgent problem to be solved by technical personnel in this field. 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 an ammonia nitrogen matching denitrification system.

[0006] To achieve the above object, the present invention adopts the following technical solutions:

[0007] A multi-dimensional coupled denitrification ammonia nitrogen matching method specifically comprises the following steps:

[0008] A plurality of ammonia spraying zones are arranged at the denitrification inlet, and a plurality of measurement zones are arranged at the denitrification outlet corresponding to the ammonia spraying zones;

[0009] The basic ammonia injection amount, the advance response ammonia injection amount and the feedback ammonia injection amount are calculated according to the system parameters, and the total ammonia injection amount is obtained by summing them up; the system parameters include the flue gas volume, the inlet NO X Concentration, outlet NO X Preset concentration, outlet NO XMeasure concentration and inlet NO within a preset time X Concentration change value, system conversion factor, system response factor and system feedback factor;

[0010] Zone leveling, including calculation of NO for each of the measurement zones X The total ammonia injection amount is injected into the corresponding ammonia injection partition according to the ratio.

[0011] Preferably, the calculation of the basic ammonia injection amount, the advance response ammonia injection amount and the feedback ammonia injection amount according to the system parameters specifically includes the following steps:

[0012] Calculate the total flue gas volume using the following formula:

[0013] Q=M×K m Or Q = F × K f ;

[0014] Calculate the basic ammonia injection amount using the following formula:

[0015] S 1 =(N R -N S )×Q×η 1 ×10 -6 ×17 / 46;

[0016] Calculate the amount of ammonia injection in advance response, the calculation formula is:

[0017] S 2 =ΔN×Q×η 2 ×10 -6 ×17 / 46;

[0018] Calculate the feedback ammonia injection amount, the calculation formula is:

[0019] S 3 =(N C -N S )×Q×η 3 ×10 -6 ×17 / 46;

[0020] Where Q is the total flue gas volume (m 3 / h, standard state, dry basis, 6% O 2 ); M is the total amount of online coal (t / h); K m is the bituminous coal conversion coefficient; F is the total online air volume (t / h); K f S is the wind and smoke conversion coefficient; 1 The basic ammonia injection amount (kg / h); N R For entrance NO X Concentration (mg / m 3 , standard state, dry basis, 6%O 2 );NS For export NO X Preset concentration (mg / m 3 , standard state, dry basis, 6%O 2 );η 1 is the system conversion coefficient, ranging from 4300 to 4700; S 2 is the amount of ammonia sprayed in advance (kg / h); ΔN is the inlet NO in the preset time. X Concentration change value; η 2 is the system response coefficient, ranging from 0.85 to 1.15; S 3 is the feedback ammonia injection amount (kg / h); N C For export NO X Measured concentration (mg / m 3 , standard state, dry basis, 6%O 2 );η 3 is the system feedback coefficient, and its value range is 0.85~1.15.

[0021] Preferably, a plurality of ammonia spraying partitions are provided at the denitration inlet, and a plurality of measurement partitions are provided at the denitration outlet corresponding to the ammonia spraying partitions; specifically, the following steps are included:

[0022] A plurality of ammonia injection zones are divided at the denitration inlet, the control area of ​​each ammonia injection zone is M1, the cross-sectional area of ​​the denitration inlet is M2, and the ratio of M2 to M1 satisfies the range of 3≦M2 / M1≦8;

[0023] A plurality of measurement zones are divided at the denitration outlet, the control area of ​​each measurement zone is M3, the cross-sectional area of ​​the denitration outlet is M4, and the ratio of M4 to M3 satisfies the range of 3≦M3 / M4≦8.

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

[0025] Selecting a number of sampling points in each of the measurement partitions;

[0026] Determine the preset position of the sampling point in the corresponding measurement partition according to the numerical simulation result of the ammonia nitrogen molar ratio;

[0027] The NO of each measurement partition is obtained in turn through the sampling points. X concentration.

[0028] Preferably, determining the preset position of the sampling point in the corresponding measurement partition according to the numerical simulation result of the ammonia nitrogen molar ratio specifically includes the following steps:

[0029] Compare the simulated NO at multiple sampling points of the denitrification outlet X Concentration data and measured NOX Concentration data, obtain comparison results;

[0030] leveling the unit according to the comparison result;

[0031] Adjust the ammonia spraying amount of the ammonia spraying zone according to the preset gradient;

[0032] Determine the amount of ammonia sprayed and the measured NO at the sampling point X Whether the concentration data is positively correlated, if so, the sampling point is located at the preset position.

[0033] Preferably, the installation of a partition measurement device is also included, which specifically includes the following steps:

[0034] A partition measuring device is installed on the inclined flue on the A or B side of the denitrification outlet, and the partition measuring device includes a sampling tube;

[0035] The pipe mouth of the sampling tube is arranged at the preset position.

[0036] Preferably, deviation leveling is also included, which specifically includes the following steps:

[0037] Set the NO of each measurement partition X The ideal value of concentration;

[0038] Set the NO of each measurement partition X Deviation range of concentration;

[0039] Get the NO of each measurement partition in turn X The measured value of concentration;

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

[0041] Determine the NO of each measurement partition X Whether the concentration difference is within the deviation range, if so, a preset amount of ammonia is injected into the corresponding ammonia injection partition.

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

[0043] Preferably, mixed sampling is also included, which specifically includes the following steps: after the system returns to a steady state, obtaining the NO X and mix.

[0044] An ammonia nitrogen matching denitrification system based on the above-mentioned multi-dimensional coupled denitrification ammonia nitrogen matching method comprises:

[0045] A zoned ammonia spraying device has a plurality of ammonia spraying zones, wherein the ammonia spraying zones are arranged at the denitrification inlet;

[0046] A partition measurement device having a plurality of measurement partitions, wherein the measurement partitions are arranged at the denitration outlet;

[0047] The total ammonia injection calculation module is used to calculate the basic ammonia injection amount, the advance response ammonia injection amount and the feedback ammonia injection amount according to the system parameters, and sum them up to obtain the total ammonia injection amount; the system parameters include the flue gas volume, the inlet NO X Concentration, outlet NO X Preset concentration, outlet NO X Measure concentration and inlet NO within a preset time X Concentration change value, system conversion factor, system response factor and system feedback factor;

[0048] The partition leveling module includes a ratio calculation unit and a control unit; the ratio calculation unit is used to calculate the NO of each measurement partition. X The control unit is used to control the partition ammonia injection device to inject ammonia into the corresponding ammonia injection partition according to the ratio.

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

[0050] The partition measurement device comprises sampling tubes arranged corresponding to the measurement partitions, and each of the sampling tubes has a plurality of sampling tube ports;

[0051] The position of the sampling tube opening is determined according to the numerical simulation result of the ammonia nitrogen molar ratio.

[0052] Compared with the prior art, the present invention has the following beneficial effects:

[0053] The above technical solution provides a multi-dimensional coupling denitrification ammonia nitrogen matching method, which is based on the flue gas volume, inlet NO X Concentration, outlet NO X Preset concentration, outlet NO X Measure concentration and inlet NO within a preset time X The concentration change value, system conversion coefficient, system response coefficient, system feedback coefficient and other system parameters are used to calculate the basic ammonia injection amount, the advance response ammonia injection amount and the feedback ammonia injection amount, so as to obtain the accurate total ammonia injection amount, and then calculate the NO XThe ratio of the concentration of the total ammonia spray amount and the total ammonia spray amount is sprayed to the corresponding ammonia spray partition according to the ratio. On the one hand, it can reduce the influence of the error caused by the system lag on the total ammonia spray amount to a certain extent, and ensure the accuracy of the total ammonia spray amount supplied; on the other hand, the total ammonia spray amount control and the partition leveling control interact with each other to ensure the accuracy of the ammonia spray control, and then ensure the denitrification system meets the emission standards, further reduce the operating cost, and ensure the efficient and economical operation of the unit. Correspondingly, the ammonia nitrogen matching denitrification system based on the multi-dimensional coupling denitrification ammonia nitrogen matching method provided in the above technical solution can realize the precise control of the total ammonia spray amount through the settings of the partition ammonia spray device, the partition measurement device, the total ammonia spray amount calculation module and the partition leveling module, and ensure the denitrification system meets the emission standards, further reduce the operating cost, and ensure the efficient and economical operation of the unit. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] 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.

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

[0056] Figure 2 for Figure 1 Schematic diagram of one example of step S2 in .

[0057] Figure 3 for Figure 1 Schematic diagram of one example of the S3 step.

[0058] Figure 4 for Figure 1 Schematic diagram of one example of step S5.

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

[0060] Description of reference numerals:

[0061] 1. Zoned ammonia injection device; 2. Zoned measuring device; 21. Sampling tube; 3. Stratified cross mixer; 4. Guide plate; 5. Rectifier; 6. Catalyst assembly; 101. Inlet flue; 102. Outlet flue. DETAILED DESCRIPTION

[0062] 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.

[0063] 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.

[0064] 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.

[0065] See also Figures 1 to 4 The embodiment of the present invention provides a multi-dimensional coupled denitrification ammonia nitrogen matching method, which specifically includes the following steps:

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

[0067] S2: Calculate the basic ammonia injection amount, the advance response ammonia injection amount and the feedback ammonia injection amount according to the system parameters, and sum them up to obtain the total ammonia injection amount. Among them, the system parameters include flue gas volume, inlet NO X Concentration, outlet 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.

[0068] S3: Partition leveling, including calculation of NO for each measurement partition X The total ammonia spray amount is injected into the corresponding ammonia spray zone according to the ratio.

[0069] S4: Mixed sampling. Specifically includes the following steps: After the system returns to a steady state, obtain the NO of each measurement partition. X and mix.

[0070] S5: Deviation leveling, used for NO according to measurement partition X Concentration deviation, dynamically adjust the amount of ammonia sprayed into each ammonia spray zone.

[0071] Specifically, the flue gas volume, inlet NO X Concentration, outlet NO X Preset concentration, outlet NO X Measure concentration and inlet NO within a preset time X The concentration change value, system conversion coefficient, system response coefficient, system feedback coefficient and other system parameters are used to calculate the basic ammonia injection amount, the advance response ammonia injection amount and the feedback ammonia injection amount, so as to obtain the accurate total ammonia injection amount, and then calculate the NO X The total ammonia injection amount is controlled by the control of the total ammonia injection amount and the zone leveling control, and the total ammonia injection amount is injected to the corresponding ammonia injection zone according to the ratio. On the one hand, it can reduce the influence of errors caused by system lag on the total ammonia injection amount to a certain extent, and ensure the accuracy of the total ammonia injection amount supplied; on the other hand, the accuracy of ammonia injection control is ensured through the interaction between the total ammonia injection amount control and the zone leveling control, thereby further reducing the operating cost and ensuring the efficient and economical operation of the unit under the condition of ensuring that the denitrification system meets the emission standards.

[0072] Specifically, the S2 step 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 supply, total air volume, primary air volume, primary air volume, main steam volume, and system conversion coefficient, etc. In this embodiment, the calculation can be performed using Formula 1 or Formula 2.

[0075] Formula 1: Q = M × K m ;

[0076] Formula 2: Q = F × K f .

[0077] Where Q is the total flue gas volume (m 3 / h, standard state, dry basis, 6% O 2 ); M is the total amount of online coal (t / h); K m is the bituminous coal conversion coefficient; F is the total online air volume (t / h); K f is the wind and smoke conversion coefficient.

[0078] It is worth noting that K mIt is the coefficient of converting the total coal volume to the flue gas volume. It is dimensionless and can be calculated by (total air volume + total coal volume) × 1000 ÷ total coal volume ÷ 1.34 ÷ 2. Correspondingly, K f It is the coefficient for converting total air volume to flue gas volume. It is dimensionless and can be calculated by (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: S 1 =(N R -N S )×Q×η 1 ×10 -6 ×17 / 46.

[0082] Among them, S 1 The basic ammonia injection amount (kg / h); N R For entrance NO X Concentration (mg / m 3 , standard state, dry basis, 6%O 2 );N S For export NO X Preset concentration (mg / m 3 , standard state, dry basis, 6%O 2 );η 1 is the system conversion coefficient, η 1 The value range is 4300~4700.

[0083] S2.3: Calculate the amount of ammonia sprayed in advance. X The concentration of NO has a certain hysteresis, therefore, the inlet NO is measured by the denitrification inlet instrument. X Concentration (mg / m 3 , standard state, dry basis, 6%O 2 ) The ammonia injection amount calculated by the system has a certain hysteresis. Therefore, calculating the advance response ammonia injection amount can improve the accuracy of the total ammonia injection amount calculation, thereby improving the control accuracy 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: S 2 =ΔN×Q×η 2 ×10 -6 ×17 / 46;

[0086] Among them, S 2is the amount of ammonia sprayed in advance (kg / h); ΔN is the inlet NO in the preset time. X Concentration change value; η 2 is the system response coefficient, and its value range is 0.85~1.15.

[0087] S2.4: Calculate the feedback ammonia injection amount.

[0088] Specifically, in this embodiment, Formula 5 can be used for calculation.

[0089] Formula 5: S 3 =(N C -N S )×Q×η 3 ×10 -6 ×17 / 46;

[0090] Among them, S 3 is the feedback ammonia injection amount (kg / h); N C For export NO X Measured concentration (mg / m 3 , standard state, dry basis, 6%O 2 );η 3 is the system feedback coefficient, and its value range is 0.85~1.15.

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

[0092] Specifically, in this embodiment, Formula 6 can be used for calculation.

[0093] Formula 6: S = S 1 +S 2 +S 3 .

[0094] Wherein, S is the total ammonia injection amount (kg / h).

[0095] It can be known that since the ammonia sprayed by the ammonia spraying device is diluted, the ammonia-air mixing ratio after dilution does not exceed 5%. When the number of measuring partitions and ammonia spraying partitions is more, the control area of ​​ammonia spraying is smaller, and the amount of ammonia spraying adjustment is correspondingly smaller, which easily leads to unclear ammonia spraying control effect. Furthermore, the control valves corresponding to the measuring partitions and ammonia spraying partitions have a throttling effect on the dilution air flow rate. Too many measuring partitions and ammonia spraying partitions will cause the dilution air to be too low and the ammonia nitrogen ratio to increase. Furthermore, when the number of ammonia spraying partitions and measuring partitions is too large, the difficulty of technical implementation increases, the cost of unit transformation is too high, and side effects of the unit such as blockage may also occur. When the number of measuring partitions and ammonia spraying partitions is too small, the purpose of refined intelligent control of the unit cannot be met. Therefore, in this embodiment, the number of measuring partitions and ammonia spraying partitions is set according to the design parameters corresponding to the unit.

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

[0097] A number of ammonia injection zones are divided at the denitration inlet, the control area of ​​each ammonia injection zone is M1, the cross-sectional area of ​​the denitration inlet is M2, and the ratio of M2 to M1 satisfies the range of 3≦M2 / M1≦8;

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

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

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

[0101] S3.1: Select a number of sampling points in each measurement area;

[0102] S3.2: Determine the preset position of the sampling point in its corresponding measurement partition according to the numerical simulation result of the ammonia nitrogen molar ratio;

[0103] S3.3: Obtain the NO of each measurement partition in turn through the sampling points X concentration.

[0104] S3.4: The heated boiler side cold primary air is transported to the sampling tube of the partition measuring device.

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

[0106] S3.2.1: Compare the simulated NO at multiple sampling points at the denitrification outlet X Concentration data and measured NO X Concentration data, obtain comparison results;

[0107] S3.2.2: Level the unit according to the comparison results. It is worth noting that the leveling unit here refers to adjusting the amount of ammonia injection to make the NO X The concentration meets the standard.

[0108] S3.2.3: Adjust the ammonia spraying amount in the ammonia spraying zone according to the preset gradient.

[0109] S3.2.4: Determine the sprayed ammonia amount and the measured NO at the sampling point X Whether the concentration data is positively correlated, if so, the sampling point is located at the preset position.

[0110] In detail, in this embodiment, the ammonia spraying amount in each area can be increased by 25%, 50%, 75%, and 100% in turn to verify the change in concentration value at the corresponding sampling point position of the denitrification outlet section. When the ammonia spraying amount in each area increases, the corresponding measuring point value also has an obvious positive correlation, which means that each ammonia spraying partition corresponds to the outlet measuring point, and the position can be considered as the preset position.

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

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

[0113] S5.1: Set the NO of each measurement zone X The ideal value of concentration;

[0114] S5.2: Set the NO of each measurement zone X Deviation range of concentration;

[0115] S5.3: Use the partition measurement device to obtain the NO of each measurement partition in turn X The measured value of concentration;

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

[0117] S5.5: Determine the NO of each measurement partition X Whether the concentration difference is within the deviation range, if so, a preset amount of ammonia is injected into the corresponding ammonia injection zone.

[0118] In order to improve the mixing effect and solve the problem of poor uniformity of the velocity field in the whole process of the denitrification system, in this embodiment, ammonia and the flue gas to be denitrified are cross-mixed downstream of each ammonia injection zone, which is not shown in the figure.

[0119] Specifically, a stratified cross mixer can be arranged in the flue within the range of 0.5 to 5 m downstream of the ammonia injection device. The cross section of the flue is a rectangular cross section. Under the action of the stratified cross mixer, the cross direction of the flue gas stratification is consistent with the short side direction of the rectangular cross section. When the long side direction of the rectangular cross section is equally divided into N ammonia injection partitions and measurement partitions, the long side direction of the rectangular cross section is divided into at least 2N groups of cross units.

[0120] See also Figure 5This embodiment also provides a denitrification ammonia nitrogen matching system based on the above-mentioned multi-dimensional coupled denitrification ammonia nitrogen matching method, including a partitioned ammonia spraying device 1, a partitioned measuring device 2, a total ammonia spraying amount calculation module, and a partitioned leveling module. Among them, the partitioned ammonia spraying device 1 has a plurality of ammonia spraying partitions, and the ammonia spraying partitions are arranged at the denitrification inlet. The partitioned measuring device 2 has a plurality of measuring partitions, and the measuring partitions are arranged at the denitrification outlet. The total ammonia spraying amount calculation module is used to calculate the basic ammonia spraying amount, the advance response ammonia spraying amount and the feedback ammonia spraying amount according to the system parameters, and sum them up to obtain the total ammonia spraying amount; wherein, the system parameters include the flue gas volume, the inlet NO X Concentration, outlet 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.

[0121] Specifically, the zoned ammonia injection device 1 is arranged at the inlet flue 101 (ie, the desulfurization inlet). The zoned ammonia injection device 1 comprises an ammonia injection grid 11, and the ammonia injection grid 11 forms a plurality of ammonia injection zones.

[0122] The partition leveling module includes a ratio calculation unit 41 and a control unit 42; the ratio calculation unit 41 is used to calculate the NO of each measurement partition. X The control unit 42 is used to control the partition ammonia spraying device to spray ammonia to the corresponding ammonia spraying partition according to the ratio.

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

[0124] See also Figure 5 , the partition measuring device 2 is arranged at the outlet flue 102 (i.e., the denitration outlet). Specifically, the partition measuring device 2 is installed on the inclined flue on the A or B side of the denitration outlet, and the partition measuring device 2 includes a sampling tube 21 arranged corresponding to the measurement partition, and each sampling tube 21 has a plurality of sampling tube openings; the position of the sampling tube opening in the measurement partition is determined according to the numerical simulation result of the ammonia nitrogen molar ratio.

[0125] See also Figure 5 The system also includes a stratified cross mixer 3, a guide plate 4, a rectifier 5, and a catalyst assembly 6, wherein the stratified cross mixer 3 is used to balance the flue gas velocity field, and the guide plate 4 is arranged in an arc-shaped structure, which can be specifically arranged according to the required flow direction of the flue gas, and then the flue gas is guided to the catalyst assembly 6; the catalyst assembly 6 is used to react with the flue gas to denitrate.

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

[0127] The above-mentioned embodiments are only preferred embodiments of the present invention and cannot be used to limit the scope of protection of the present invention. Any non-substantial changes and substitutions made by technicians in this field on the basis of the present invention shall fall within the scope of protection required by the present invention.

Claims

1. A multi-dimensional coupled denitrification ammonia nitrogen matching method, characterized in that: The specific steps include: A plurality of ammonia spraying zones are arranged at the denitrification inlet, and a plurality of measurement zones are arranged at the denitrification outlet corresponding to the ammonia spraying zones; The basic ammonia injection amount, the advance response ammonia injection amount and the feedback ammonia injection amount are calculated according to the system parameters, and the total ammonia injection amount is obtained by summing them up; the system parameters include the flue gas volume, the inlet NO X Concentration, outlet NO X Preset concentration, outlet NO X Measure concentration and inlet NO within a preset time X Concentration change value, system conversion factor, system response factor and system feedback factor; Zone leveling, including calculation of NO for each of the measurement zones X The total ammonia injection amount is injected into the corresponding ammonia injection partition according to the ratio.

2. The multi-dimensional coupled denitrification ammonia nitrogen matching method according to claim 1, characterized in that: The method of calculating the basic ammonia injection amount, the advance response ammonia injection amount and the feedback ammonia injection amount according to the system parameters specifically includes the following steps: Calculate the total flue gas volume using the following formula: Q=M×K m Or Q = F × K f ; Calculate the basic ammonia injection amount using the following formula: S1=(N R -N S )×Q×η1×10 -6 ×17 / 46; Calculate the amount of ammonia injection in advance response, the calculation formula is: <h2 style=";text-align:left;direction:ltr">S2 = ΔN×Q×η2×10<h2 style=";text-align:left;direction:ltr"> -6 <h2 style=";text-align:left;direction:ltr"> ×17 / 46; Calculate the feedback ammonia injection amount, the calculation formula is: S3=(N C -N S )×Q×η3×10 -6 ×17 / 46; Where Q is the total flue gas volume (m 3 / h, standard state, dry basis, 6% O2); M is the total amount of coal online (t / h); K m is the bituminous coal conversion coefficient; F is the total online air volume (t / h); K f is the wind and smoke conversion coefficient; S1 is the basic ammonia injection amount (kg / h); N R For entrance NO X Concentration (mg / m 3 , standard state, dry basis, 6% O2); N S For export NO X Preset concentration (mg / m 3 , standard state, dry basis, 6% O2); η1 is the system conversion coefficient, ranging from 4300 to 4700; S2 is the advance response ammonia injection amount (kg / h); ΔN is the inlet NO in the preset time X concentration change value; η2 is the system response coefficient, ranging from 0.85 to 1.15; S3 is the feedback ammonia injection amount (kg / h); N C For export NO X Measured concentration (mg / m 3 , standard state, dry basis, 6% O2); η3 is the system feedback coefficient, and its value range is 0.85~1.

15.

3. The multi-dimensional coupled denitrification ammonia nitrogen matching method according to claim 1, characterized in that: The method comprises the following steps: setting a plurality of ammonia spraying zones at the denitration inlet and setting a plurality of measurement zones at the denitration outlet corresponding to the ammonia spraying zones. A plurality of ammonia injection zones are divided at the denitration inlet, the control area of ​​each ammonia injection zone is M1, the cross-sectional area of ​​the denitration inlet is controlled as M2, and the value range of the ratio of M2 to M1 satisfies: 3≤M2 / M1≤8; A plurality of measurement zones are divided at the denitration outlet, the control area of ​​each measurement zone is M3, the cross-sectional area of ​​the denitration outlet is M4, and the ratio of M4 to M3 satisfies the range of 3≤M4 / M3≤8.

4. The multi-dimensional coupled denitrification ammonia nitrogen matching method according to claim 3, characterized in that: The partition leveling further includes the following steps: Selecting a number of sampling points in each of the measurement partitions; Determine the preset position of the sampling point in the corresponding measurement partition according to the numerical simulation result of the ammonia nitrogen molar ratio; The NO of each measurement partition is obtained in turn through the sampling points. X concentration.

5. The multi-dimensional coupled denitrification ammonia nitrogen matching method according to claim 4, characterized in that: Determining the preset position of the sampling point in the corresponding measurement partition according to the numerical simulation result of the ammonia nitrogen molar ratio specifically includes the following steps: Compare the simulated NO at multiple sampling points of the denitrification outlet X Concentration data and measured NO X Concentration data, obtain comparison results; leveling the unit according to the comparison result; Adjust the ammonia spraying amount of the ammonia spraying zone according to the preset gradient; Determine the amount of ammonia sprayed and the measured NO at the sampling point X Whether the concentration data is positively correlated, if so, the sampling point is located at the preset position.

6. The multi-dimensional coupled denitrification ammonia nitrogen matching method according to claim 4 or 5, further comprising the installation of a partition measurement device, specifically comprising the following steps: A partition measuring device is installed on the inclined flue on the A or B side of the denitrification outlet, and the partition measuring device includes a sampling tube; The pipe mouth of the sampling tube is arranged at the preset position.

7. The multi-dimensional coupled denitrification ammonia nitrogen matching method according to claim 1, characterized in that: It also includes deviation leveling, which includes the following steps: Set the NO of each measurement partition X The ideal value of concentration; Set the NO of each measurement partition X Deviation range of concentration; Get the NO of each measurement partition in turn X The measured value of concentration; Calculating the difference between the ideal value and the measured value; Determine the NO of each measurement partition X Whether the concentration difference is within the deviation range, if so, a preset amount of ammonia is injected into the corresponding ammonia injection partition.

8. The multi-dimensional coupled denitrification ammonia nitrogen matching method according to claim 1, characterized in that: It also includes cross-mixing of ammonia and flue gas to be denitrified downstream of each of the ammonia injection zones.

9. The multi-dimensional coupled denitrification ammonia nitrogen matching method according to claim 1, characterized in that: It also includes mixed sampling, which specifically includes the following steps: after the system returns to a steady state, obtain the NO in each measurement partition. X and mix.

10. An ammonia nitrogen matching denitrification system based on the multi-dimensional coupled denitrification ammonia nitrogen matching method according to any one of claims 1 to 9, characterized in that: include, A zoned ammonia spraying device has a plurality of ammonia spraying zones, wherein the ammonia spraying zones are arranged at the denitrification inlet; A partition measurement device having a plurality of measurement partitions, wherein the measurement partitions are arranged at the denitration outlet; The total ammonia injection calculation module is used to calculate the basic ammonia injection amount, the advance response ammonia injection amount and the feedback ammonia injection amount according to the system parameters, and sum them up to obtain the total ammonia injection amount; the system parameters include the flue gas volume, the inlet NO X Concentration, outlet NO X Preset concentration, outlet NO X Measure concentration and inlet NO within a preset time X Concentration change value, system conversion factor, system response factor and system feedback factor; The partition leveling module includes a ratio calculation unit and a control unit; the ratio calculation unit is used to calculate the NO of each measurement partition. X The control unit is used to control the partition ammonia injection device to inject ammonia into the corresponding ammonia injection partition according to the ratio.

11. The ammonia nitrogen matching denitrification system according to claim 10, characterized in that: The partition measurement device is installed on the A / B side inclined flue of the denitrification outlet; The partition measurement device comprises sampling tubes arranged corresponding to the measurement partitions, and each of the sampling tubes has a plurality of sampling tube ports; The position of the sampling tube opening is determined according to the numerical simulation result of the ammonia nitrogen molar ratio.

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