Ammonia Injection Method and Apparatus Based on Denitrification System

Abstract

This disclosure provides an ammonia injection method and apparatus based on a denitrification system. The method includes: acquiring current boiler parameters of a coal-fired boiler; collecting nitrogen oxide (NOx) parameters at the denitrification inlet of the denitrification system as a first NOx parameter; collecting NOx parameters at the denitrification outlet of the denitrification system as a second NOx parameter; collecting NOx parameters at the total exhaust outlet of the denitrification system as a third NOx parameter; preprocessing the current boiler parameters, the first NOx parameter, the second NOx parameter, and the third NOx parameter respectively; determining the current required ammonia quantity for the denitrification system based on at least one of the preprocessed current boiler parameters, the first NOx parameter, the second NOx parameter, and the third NOx parameter; and injecting ammonia into the denitrification system according to the current required ammonia quantity. This method ensures that the calculated ammonia injection quantity is significantly more accurate.

Description

Technical Field

[0001] This disclosure relates to the field of industrial flue gas denitrification control, and in particular to the field of ammonia injection technology based on denitrification systems. Background Technology

[0002] Currently, environmental protection requirements are becoming increasingly stringent, with higher standards for the quality of flue gas emitted by power plants and other factories. The concentration of nitrogen oxides (NOx) in the flue gas from coal-fired boilers and other industrial equipment must meet certain conditions before emissions can proceed; otherwise, air quality will be affected, causing environmental pollution. To reduce the concentration of NOx to a certain level, ammonia injection is required through a denitrification system. Specifically, after NOx and ammonia enter the denitrification system, they are converted into nitrogen and water under the action of a catalyst, thereby reducing the concentration of NOx. However, if this ammonia injection process is performed manually, it can result in either excessive or insufficient injection. Excessive injection can cause blockage of the air preheater in power plant boilers, while insufficient injection (insufficient NOx removal) will lead to failure to meet environmental standards. Therefore, automatic control with high precision, reliability, and robustness is required. Thus, how to accurately control the amount of ammonia injected has become an urgent problem to be solved. Summary of the Invention

[0003] This disclosure provides a method, apparatus, equipment, and storage medium for ammonia injection based on a denitrification system.

[0004] According to a first aspect of this disclosure, an ammonia injection method based on a denitrification system is provided. The method includes:

[0005] Obtain the current boiler parameters of the coal-fired boiler;

[0006] The nitrogen oxide parameters at the denitrification inlet of the denitrification system are collected as the first nitrogen oxide parameter;

[0007] The nitrogen oxide parameters at the denitrification outlet of the denitrification system are collected as a second nitrogen oxide parameter;

[0008] The nitrogen oxide parameters of the total exhaust port of the denitrification system are collected as the third nitrogen oxide parameter;

[0009] The current boiler parameters, the first nitrogen oxide parameter, the second nitrogen oxide parameter, and the third nitrogen oxide parameter are preprocessed respectively.

[0010] The required ammonia amount for the denitrification system is determined based on at least one of the pre-processed current boiler parameters, the first nitrogen oxide parameter, the second nitrogen oxide parameter, and the third nitrogen oxide parameter.

[0011] Ammonia is injected into the denitrification system according to the current required ammonia amount.

[0012] In addition to the aspects and any possible implementations described above, a further implementation is provided, wherein the preprocessing of the current boiler parameters, the first nitrogen oxide parameter, the second nitrogen oxide parameter, and the third nitrogen oxide parameter includes:

[0013] Based on the current temperature and pressure at each measurement point of the current boiler parameters, the first nitrogen oxide parameter, the second nitrogen oxide parameter, and the third nitrogen oxide parameter, the concentration units of the current boiler parameters, the first nitrogen oxide parameter, the second nitrogen oxide parameter, and the third nitrogen oxide parameter are uniformly converted.

[0014] The denitrification inlet, the denitrification outlet, and the main exhaust port are purged.

[0015] Anomaly tracking is performed on the parameters of the denitrification inlet and the denitrification outlet.

[0016] In addition to the aspects and any possible implementations described above, a further implementation is provided in which the parameter anomaly tracking of the denitrification inlet and the denitrification outlet includes:

[0017] When there are multiple denitrification inlets, if all of the denitrification inlets are in normal working condition, the first nitrogen oxide parameter collected at each of the denitrification inlets is retained; otherwise, if any of the denitrification inlets is in abnormal working condition, the value of the first nitrogen oxide parameter of any of the denitrification inlets is taken from the value of the first nitrogen oxide parameter of the other denitrification inlets.

[0018] When there are multiple denitrification outlets, if all of the denitrification outlets are in normal working condition, the second nitrogen oxide parameter collected from each of the denitrification outlets is retained; otherwise, if any of the denitrification outlets is in abnormal working condition, the value of the second nitrogen oxide parameter of any denitrification outlet is taken from the value of the second nitrogen oxide parameter of the other denitrification outlets.

[0019] In addition to the aspects and any possible implementations described above, a further implementation is provided in which the parameter anomaly tracking of the denitrification inlet and the denitrification outlet includes:

[0020] When there is only one denitrification inlet, if the denitrification inlet is in normal working condition, the first nitrogen oxide parameter collected by the denitrification inlet is retained; otherwise, if the denitrification inlet is in abnormal working condition, the value of the first nitrogen oxide parameter of the denitrification inlet is taken from the historical value of the first nitrogen oxide parameter of the denitrification inlet.

[0021] When there is only one denitrification outlet, if the denitrification outlet is in normal working condition, the second nitrogen oxide parameter collected at the denitrification outlet is retained; otherwise, if the denitrification outlet is in abnormal working condition, the value of the second nitrogen oxide parameter at the denitrification outlet is taken from the historical value of the second nitrogen oxide parameter at the denitrification outlet.

[0022] In addition to the aspects and any possible implementations described above, a further implementation is provided, wherein the preprocessing of the current boiler parameters, the first nitrogen oxide parameter, the second nitrogen oxide parameter, and the third nitrogen oxide parameter includes:

[0023] The current boiler parameters, the first nitrogen oxide parameter, the second nitrogen oxide parameter, and the third nitrogen oxide parameter are filtered using a moving average filtering algorithm to obtain their respective filtered mean values.

[0024] The current boiler parameters, the first nitrogen oxide parameter, the second nitrogen oxide parameter, and the third nitrogen oxide parameter are compared with their respective corresponding filtered mean values ​​to obtain the final current boiler parameters, the final first nitrogen oxide parameter, the final second nitrogen oxide parameter, and the final third nitrogen oxide parameter.

[0025] In addition to the aspects and any possible implementations described above, a further implementation is provided, wherein determining the current required ammonia amount for the denitrification system based on at least one of the preprocessed current boiler parameters, the first nitrogen oxide parameter, the second nitrogen oxide parameter, and the third nitrogen oxide parameter includes:

[0026] Based on the current boiler parameters, determine the corresponding first target ammonia quantity;

[0027] Calculate the second target ammonia quantity based on the current boiler parameters, the first nitrogen oxide parameter, and the second nitrogen oxide parameter;

[0028] Calculate the third target ammonia quantity based on the current boiler parameters and the second nitrogen oxide parameters;

[0029] Calculate the fourth target ammonia amount based on the first nitrogen oxide parameter, the second nitrogen oxide parameter, and the third nitrogen oxide parameter;

[0030] The required ammonia amount for the denitrification system is determined based on the first target ammonia amount, the second target ammonia amount, the third target ammonia amount, and the fourth target ammonia amount.

[0031] In addition to the aspects and any possible implementations described above, a further implementation is provided, wherein determining the corresponding first target ammonia quantity based on the current boiler parameters includes:

[0032] Obtain historical boiler parameters;

[0033] Calculate the boiler parameter difference between the current boiler parameters and the historical boiler parameters;

[0034] The first target ammonia quantity is calculated based on the difference in the boiler parameters.

[0035] In addition to the aspects and any possible implementations described above, a further implementation is provided, wherein the current boiler parameters include the current furnace air volume of the boiler; the calculation of the second target ammonia quantity based on the current boiler parameters, the first nitrogen oxide parameter, and the second nitrogen oxide parameter includes:

[0036] Obtain the nitrogen oxide setpoint at the total exhaust port and the nitrogen oxide setpoint at the denitrification outlet;

[0037] Obtain the actual ammonia injection rate of the denitrification system;

[0038] Determine the start and stop times of the coal mill;

[0039] The second target ammonia quantity is calculated based on the current furnace air volume, the first nitrogen oxide parameter, the second nitrogen oxide parameter, the nitrogen oxide setpoint of the total exhaust port, the nitrogen oxide setpoint of the denitrification outlet, the actual ammonia injection quantity, and the start-up and shutdown times.

[0040] In addition to the aspects and any possible implementations described above, a further implementation is provided, wherein calculating the second target ammonia quantity based on the current furnace air volume, the first nitrogen oxide parameter, the second nitrogen oxide parameter, the nitrogen oxide setpoint of the total exhaust port, the nitrogen oxide setpoint of the denitrification outlet, the actual ammonia injection quantity, and the start-up / shutdown time includes:

[0041] Calculate the first preset ammonia amount based on the first nitrogen oxide parameter, the nitrogen oxide set value at the denitrification outlet, and the current furnace air volume;

[0042] The second preset ammonia quantity is calculated based on the second nitrogen oxide parameter, the nitrogen oxide set value at the denitrification outlet, and the current furnace air volume;

[0043] Determine the third preset ammonia quantity corresponding to the start / stop time;

[0044] Obtain historical theoretical ammonia injection volume;

[0045] The difference between the historical theoretical ammonia injection amount and the current actual ammonia injection amount is calculated and used as the fourth preset ammonia amount;

[0046] The first preset ammonia amount, the second preset ammonia amount, the third preset ammonia amount, and the fourth preset ammonia amount are weighted and summed to obtain the second target ammonia amount.

[0047] In addition to the aspects and any possible implementations described above, a further implementation is provided, wherein calculating the second preset ammonia quantity based on the second nitrogen oxide parameter, the nitrogen oxide setpoint at the denitrification outlet, and the current furnace air volume includes:

[0048] Every preset time interval, it is determined whether the second nitrogen oxide parameter is greater than the nitrogen oxide set value at the denitrification outlet;

[0049] If the second nitrogen oxide parameter is greater than the nitrogen oxide set value at the denitrification outlet and the second nitrogen oxide parameter continues to increase within the first preset time period, then the second preset ammonia amount is calculated based on the second nitrogen oxide parameter, the nitrogen oxide set value at the denitrification outlet, and the current furnace air volume.

[0050] or

[0051] Every preset time interval, it is determined whether the second nitrogen oxide parameter is less than the nitrogen oxide set value at the denitrification outlet;

[0052] If the second nitrogen oxide parameter is less than the nitrogen oxide set value at the denitrification outlet and the second nitrogen oxide parameter continues to decrease within the second preset time period, then the second preset ammonia quantity is calculated based on the second nitrogen oxide parameter, the nitrogen oxide set value at the denitrification outlet, and the current furnace air volume.

[0053] According to a second aspect of this disclosure, an ammonia injection device based on a denitrification system is provided. This device is suitable for a denitrification system, wherein a coal-fired boiler is connected upstream of the denitrification system, the coal-fired boiler is used to burn pulverized coal to generate flue gas and to introduce the flue gas into the denitrification system, the denitrification system is used to denitrify the flue gas, and a coal mill is connected upstream of the coal-fired boiler, the coal mill is used to grind coal lumps into pulverized coal and to supply the pulverized coal to the coal-fired boiler. The device includes:

[0054] The acquisition module is used to acquire the current boiler parameters of the coal-fired boiler;

[0055] The first acquisition module is used to acquire the nitrogen oxide parameters at the denitrification inlet of the denitrification system as the first nitrogen oxide parameter;

[0056] The second acquisition module is used to acquire the nitrogen oxide parameters at the denitrification outlet of the denitrification system as the second nitrogen oxide parameters;

[0057] The third acquisition module is used to acquire the nitrogen oxide parameters of the total exhaust port of the denitrification system as the third nitrogen oxide parameter;

[0058] The preprocessing module is used to preprocess the current boiler parameters, the first nitrogen oxide parameter, the second nitrogen oxide parameter, and the third nitrogen oxide parameter respectively.

[0059] The determination module is used to determine the current ammonia amount required by the denitrification system based on at least one of the preprocessed current boiler parameters, the first nitrogen oxide parameter, the second nitrogen oxide parameter, and the third nitrogen oxide parameter;

[0060] The ammonia injection module is used to inject ammonia into the denitrification system according to the currently required ammonia amount.

[0061] According to a third aspect of this disclosure, an electronic device is provided. The electronic device includes a memory and a processor, wherein the memory stores a computer program, and the processor executes the program to implement the method described above.

[0062] According to a fourth aspect of this disclosure, a computer-readable storage medium is provided having a computer program stored thereon that, when executed by a processor, implements the method according to a first aspect of this disclosure.

[0063] In this disclosure, by acquiring the current boiler parameters of the coal-fired boiler, the first nitrogen oxide parameters, the second nitrogen oxide parameters, and the third nitrogen oxide parameters of the denitrification system, and then preprocessing the current boiler parameters, the first nitrogen oxide parameters, the second nitrogen oxide parameters, and the third nitrogen oxide parameters respectively, it can be ensured that these parameters have consistent units and that the data is valid and without anomalies. Then, by using at least one of these parameters for reasonable calculation, it can be ensured that the current ammonia amount required by the denitrification system can be accurately calculated by comprehensively considering multiple different parameters of the denitrification system and the equipment associated with the denitrification system. Then, ammonia is automatically injected into the denitrification system according to the current required ammonia amount. In this way, the need for manual calculation of the ammonia injection amount can be avoided, and the ammonia injection amount calculated by comprehensively considering different parameters is obviously more accurate, improving the ammonia injection accuracy of the denitrification system and realizing the automation, accuracy, reliability, and robustness of ammonia injection in the denitrification system.

[0064] It should be understood that the description in the Summary of the Invention is not intended to limit the key or essential features of the embodiments of this disclosure, nor is it intended to restrict the scope of this disclosure. Other features of this disclosure will become readily apparent from the following description. Attached Figure Description

[0065] The above and other features, advantages, and aspects of the embodiments of this disclosure will become more apparent from the accompanying drawings and the following detailed description. The drawings are provided for a better understanding of the invention and are not intended to limit the scope of this disclosure. In the drawings, the same or similar reference numerals denote the same or similar elements, wherein:

[0066] Figure 1 A schematic diagram illustrating the connection relationship of a denitrification system according to an embodiment of the present disclosure is shown.

[0067] Figure 2 A flowchart of an ammonia quantity control method according to an embodiment of the present disclosure is shown;

[0068] Figures 3A to 3D The curves showing the variation of a first preset ammonia amount, a second preset ammonia amount, a third preset ammonia amount, and a fourth preset ammonia amount over time according to embodiments of the present disclosure are illustrated.

[0069] Figure 4 A block diagram of an ammonia quantity control device according to an embodiment of the present disclosure is shown;

[0070] Figure 5 A block diagram of an exemplary electronic device capable of implementing embodiments of the present disclosure is shown. Detailed Implementation

[0071] To make the objectives, technical solutions, and advantages of the embodiments of this disclosure clearer, the technical solutions of the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this disclosure, and not all embodiments. Based on the embodiments of this disclosure, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this disclosure.

[0072] Furthermore, the term "and / or" in this article is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, the character " / " in this article generally indicates that the preceding and following related objects have an "or" relationship.

[0073] Figure 2 A flowchart of an ammonia injection method 200 based on a denitrification system according to an embodiment of the present disclosure is shown. The method 200 is applicable to a denitrification system, the function of which is to: after ammonia injection, allow nitrogen oxides to fully mix with ammonia, and then, under the action of a catalyst, generate nitrogen gas and water, with the connection relationship as follows... Figure 1As shown, a coal-fired boiler is connected upstream of the denitrification system. The coal-fired boiler is used to burn pulverized coal to generate flue gas and introduce the flue gas into the denitrification system. The denitrification system is used to denitrify the flue gas. A coal mill is connected upstream of the coal-fired boiler. The coal mill is used to grind coal lumps into pulverized coal and supply the pulverized coal to the coal-fired boiler. The method further includes:

[0074] Step 210: Obtain the current boiler parameters of the coal-fired boiler;

[0075] Step 220: Collect the nitrogen oxide parameters at the denitrification inlet of the denitrification system as the first nitrogen oxide parameter;

[0076] like Figure 1 As shown, the denitrification inlet is the inlet of the catalyst layer in the denitrification system, which is used to allow flue gas and injected ammonia to enter the catalyst layer so that nitrogen oxides and ammonia in the flue gas can react under the action of the catalyst; the denitrification outlet is the outlet of the catalyst layer in the denitrification system, which is used to discharge the gas, liquid and unreacted residual nitrogen oxides or ammonia after the reaction; the total exhaust port is equivalent to the chimney outlet of the denitrification system, which is used to discharge the gas in the denitrification system at the end.

[0077] Step 230: Collect the nitrogen oxide parameters at the denitrification outlet of the denitrification system as the second nitrogen oxide parameter;

[0078] Step 240: Collect the nitrogen oxide parameters of the total exhaust port of the denitrification system as the third nitrogen oxide parameter;

[0079] Step 250: Preprocess the current boiler parameters, the first nitrogen oxide parameter, the second nitrogen oxide parameter, and the third nitrogen oxide parameter respectively;

[0080] Step 260: Determine the current required ammonia amount (such as ammonia concentration or mass) for the denitrification system based on at least one of the pre-processed current boiler parameters, the first nitrogen oxide parameter, the second nitrogen oxide parameter, and the third nitrogen oxide parameter.

[0081] Step 270: Inject ammonia into the denitrification system according to the currently required ammonia amount.

[0082] By acquiring the current boiler parameters of the coal-fired boiler, and the first, second, and third nitrogen oxide parameters of the denitrification system, and then preprocessing these parameters individually, it can be ensured that the units of these parameters are consistent, the data is valid and without anomalies. Then, by using at least one of these parameters for reasonable calculation, it is possible to accurately calculate the current ammonia quantity required by the denitrification system based on multiple different parameters of the denitrification system and related equipment. Ammonia is then automatically injected into the denitrification system according to this current required ammonia quantity. This avoids the need for manual calculation of the ammonia injection quantity, and the ammonia injection quantity calculated by integrating different parameters is obviously more accurate, improving the ammonia injection precision of the denitrification system and achieving automation, accuracy, reliability, and robustness in ammonia injection.

[0083] In one embodiment, the preprocessing of the current boiler parameters, the first nitrogen oxide parameter, the second nitrogen oxide parameter, and the third nitrogen oxide parameter includes:

[0084] Based on the current temperature and pressure at each measurement point of the current boiler parameters, the first nitrogen oxide parameter, the second nitrogen oxide parameter, and the third nitrogen oxide parameter, the concentration units of the current boiler parameters, the first nitrogen oxide parameter, the second nitrogen oxide parameter, and the third nitrogen oxide parameter are uniformly converted.

[0085] The specific values ​​of these parameters may come from different sensors. To facilitate subsequent calculations and analysis, it is necessary to standardize the units of these parameters; for example:

[0086] The first nitrogen oxide parameter may come from different sensors, and its unit may be ppm (volume concentration) or expressed directly as mass concentration (e.g., milligrams per cubic meter). In order to unify the units and facilitate subsequent calculations and analysis, the unit conversion of the raw data is necessary.

[0087] Formula derivation

[0088] The formula for converting the NOx concentration (first nitrogen oxide parameter) at the denitrification inlet from ppm to milligrams per cubic meter is as follows:

[0089] NOx concentration (mg / m³) = NOx concentration (ppm) * molar mass * pressure / (gas constant * temperature)

[0090] in:

[0091] • NOx concentration (mg / m³): The mass concentration of NOx, expressed in milligrams per cubic meter;

[0092] • NOx concentration (ppm): The volume concentration of NOx, expressed in ppm;

[0093] • Molar mass: The molar mass of NOx (usually taken as 46 grams per mole, assuming that the main component of NOx is nitrogen dioxide);

[0094] • Pressure: Gas pressure at the denitrification inlet, measured in Pascals;

[0095] • Gas constant: approximately 8.314 joules per mole Kelvin;

[0096] • Temperature: Absolute temperature of the gas at the denitrification inlet, in Kelvin.

[0097] Implementation steps

[0098] 1. Acquire the raw data and its units transmitted from the sensor;

[0099] 2. Convert the ppm unit data to milligrams per cubic meter using the formula above;

[0100] 3. If the input data is already in milligrams per cubic meter, no conversion is needed; proceed directly to the next step.

[0101] Precautions

[0102] Environmental parameters (such as temperature and pressure) need to be acquired in real time to ensure the accuracy of unit conversion;

[0103] If the sensor only provides nitric oxide data, the NOx concentration needs to be estimated based on chemical reaction relationships.

[0104] For example, different measuring devices may use different units (such as ppm or mg / m³). 3 First, it is necessary to standardize the units of the NOx concentration at the denitrification outlet (i.e., the second nitrogen oxide parameter).

[0105]

[0106] The parameters in the formula are explained as follows:

[0107] • M: Molecular weight of NOx (usually taken as 46 g / mol);

[0108] • P: Pressure at the denitrification outlet, measured in Pascals (Pa);

[0109] •T: Temperature at the denitrification outlet, measured in degrees Celsius (°C);

[0110] • T0: Standard state temperature, fixed at 0℃;

[0111] • Objective: To standardize all measurement data to mg / m3 for easier subsequent processing.

[0112] The denitrification inlet, the denitrification outlet, and the main exhaust port are purged.

[0113] Purge is necessary to prevent excessive dust or impurities from accumulating at these inlets and outlets.

[0114] Anomaly tracking is performed on the parameters of the denitrification inlet and the denitrification outlet.

[0115] When there is leakage or blockage at the inlet and outlet, the collected parameters may be abnormal. Therefore, by tracking parameter anomalies, we can ensure that the measured values ​​of these parameters do not deviate from the true values, or even if they do deviate from the true values, they will only deviate slightly, thereby ensuring the accuracy of these parameters.

[0116] Of course, the way to determine whether these parameters are abnormal is to compare the current value of these parameters with their historical values. If the difference with their historical values ​​is small, it means that they are not abnormal and the parameters are normal; otherwise, if the difference with their historical values ​​is large, it means that they are abnormal and the parameters are not normal.

[0117] In one embodiment, the step of tracking parameter anomalies at the denitrification inlet and the denitrification outlet includes:

[0118] When there are multiple denitrification inlets, if all of the denitrification inlets are in normal working condition, the first nitrogen oxide parameter collected at each of the denitrification inlets is retained; otherwise, if any of the denitrification inlets is in abnormal working condition, the value of the first nitrogen oxide parameter of any of the denitrification inlets is taken from the value of the first nitrogen oxide parameter of the other denitrification inlets.

[0119] When there are multiple denitrification inlets, if all of the denitrification inlets are in normal working condition, it indicates that the first nitrogen oxide parameter currently collected by each denitrification inlet is relatively accurate and without abnormalities. Therefore, the values ​​of the first nitrogen oxide parameters collected by each denitrification inlet can be retained for quick use of these parameters. However, if any of the denitrification inlets is in an abnormal working condition, it indicates that the first nitrogen oxide parameter collected by that denitrification inlet is inaccurate and abnormal. This could be due to a malfunction in the sensor collecting the nitrogen oxide parameter, or abnormalities such as dust purging at the denitrification inlet or air leakage or blockage in the pipes connected to the denitrification inlet. In this case, the value of the first nitrogen oxide parameter collected by that denitrification inlet cannot be retained. Instead, the value of the first nitrogen oxide parameter of that denitrification inlet needs to be determined based on the values ​​of the first nitrogen oxide parameters of the other denitrification inlets. This ensures that even if one denitrification inlet is abnormal, the values ​​of other denitrification inlets can still be tracked, thereby ensuring the accuracy of the first nitrogen oxide parameter of that denitrification inlet.

[0120] For example, when the system is configured in dual denitrification inlet mode, if NOx data from one inlet is lost due to calibration or purging, the system will automatically switch to the NOx data from the other inlet as a replacement. The specific logic is as follows:

[0121] 1. Check if the current inlet is in calibration or purging state;

[0122] 2. If so, read NOx data from the other entry point;

[0123] 3. Ensure that the data on both sides are synchronized in time to avoid introducing additional errors.

[0124] In one embodiment, when there are multiple denitrification outlets, if all of the multiple denitrification outlets are in normal working condition, the second nitrogen oxide parameter collected at each of the denitrification outlets is retained; otherwise, if any of the multiple denitrification outlets is in abnormal working condition, the value of the second nitrogen oxide parameter of any of the denitrification outlets is taken from the value of the second nitrogen oxide parameter of the remaining denitrification outlets among the multiple denitrification outlets.

[0125] When there are multiple denitrification outlets, if all of them are in normal working condition, it indicates that the second nitrogen oxide parameter collected by each denitrification outlet is relatively accurate and without abnormalities. Therefore, the value of the second nitrogen oxide parameter collected by each denitrification outlet can be retained for quick use. However, if any of the denitrification outlets is in an abnormal working condition, it indicates that the second nitrogen oxide parameter collected by that outlet is inaccurate and abnormal. This could be due to a faulty sensor for collecting nitrogen oxide parameters, or abnormalities such as dust collection and purging at the denitrification outlet, or leaks or blockages in the pipes connected to the denitrification outlet. In this case, the value of the second nitrogen oxide parameter collected by that outlet cannot be retained. Instead, the value of the second nitrogen oxide parameter of that outlet needs to be determined based on the values ​​of the second nitrogen oxide parameters of the other denitrification outlets. This ensures that even if one denitrification outlet is abnormal, the values ​​of other denitrification outlets can still be tracked, thereby ensuring the accuracy of the second nitrogen oxide parameter of that outlet and ensuring data continuity.

[0126] For example, during NOx measurement at the denitrification outlet, abnormal situations such as calibration, purging, leakage, or blockage may occur, leading to data loss or unavailability. In such cases, it is necessary to switch to a backup data source.

[0127] • Dual denitrification outlet mode: When one denitrification outlet is being calibrated or purged, switch to the NOx data of the other denitrification outlet.

[0128] • Single denitrification outlet mode: When the single denitrification outlet is being calibrated or purged, switch to the total exhaust port NOx data.

[0129] Logical judgment:

[0130] • If the channel connected to the current denitrification outlet is in normal condition, then its own measurement value is used.

[0131] • If the channel connected to the current denitrification outlet is in an abnormal state, the NOx data of the other denitrification outlet will be used first; if there is no NOx data of the other denitrification outlet, the NOx data of the main exhaust port will be used.

[0132] Of course, a threshold alarm mechanism can be set up to deal with abnormal situations such as leakage or blockage at the denitrification inlet and outlet:

[0133] 1. Real-time monitoring of NOx concentration change rate;

[0134] 2. If the rate of change exceeds a reasonable range, an alarm will be triggered and the investigation process will be initiated;

[0135] 3. After the investigation is completed, recalibrate the sensor.

[0136] In one embodiment, the step of tracking parameter anomalies at the denitrification inlet and the denitrification outlet includes:

[0137] When there is only one denitrification inlet, if the denitrification inlet is in normal working condition, the first nitrogen oxide parameter collected by the denitrification inlet is retained; otherwise, if the denitrification inlet is in abnormal working condition, the value of the first nitrogen oxide parameter of the denitrification inlet is taken from the historical value of the first nitrogen oxide parameter of the denitrification inlet.

[0138] When there is only one denitrification outlet, if the denitrification outlet is in normal working condition, the second nitrogen oxide parameter collected at the denitrification outlet is retained; otherwise, if the denitrification outlet is in abnormal working condition, the value of the second nitrogen oxide parameter at the denitrification outlet is taken from the historical value of the second nitrogen oxide parameter at the denitrification outlet.

[0139] When there is only one denitrification inlet, if the inlet is in normal working condition, it indicates that the first nitrogen oxide parameter collected by the inlet is relatively accurate and without abnormalities. Therefore, the value of the first nitrogen oxide parameter collected by the inlet can be retained for quick use. However, if the inlet is in abnormal working condition, it indicates that the first nitrogen oxide parameter collected by the inlet is inaccurate and abnormal. This could be due to a malfunction in the sensor collecting the nitrogen oxide parameter, or abnormalities such as ash purging at the denitrification inlet or air leakage or blockage in the pipes connected to the inlet. In this case, the value of the first nitrogen oxide parameter collected by the inlet cannot be retained. However, since there are no other denitrification inlets to track, the value of the first nitrogen oxide parameter of the inlet can be determined based on its historical value. For example, the average value of the historical values ​​of the first nitrogen oxide parameter of the inlet or the most recent historical value can be used as the value of the first nitrogen oxide parameter of the inlet to ensure the accuracy of the first nitrogen oxide parameter of any denitrification inlet.

[0140] When there is only one denitrification outlet, if the outlet is operating normally, it indicates that the second nitrogen oxide parameter collected by the outlet is accurate and without abnormalities. Therefore, the value of the second nitrogen oxide parameter collected at this outlet can be retained for quick use. However, if the outlet is operating abnormally, it indicates that the second nitrogen oxide parameter collected by the outlet is inaccurate and abnormal. This could be due to a malfunction in the sensor collecting the nitrogen oxide parameter, or abnormalities such as ash purging at the outlet or leaks or blockages in the pipes connected to the outlet. In this case, the value of the second nitrogen oxide parameter collected at this outlet cannot be retained. Since there are no other denitrification outlets to track, the value of the second nitrogen oxide parameter at this outlet can be determined based on its historical value. For example, the average of the historical values ​​or the most recent historical value can be used as the value of the second nitrogen oxide parameter at this outlet to ensure the accuracy of the second nitrogen oxide parameter at any given outlet.

[0141] For example, in single denitrification inlet mode, data cannot be obtained from other flues during calibration or purging. In this case, a data retention strategy is employed.

[0142] 1. Record the last valid measurement value at the denitrification inlet;

[0143] 2. Use this value as a temporary alternative during the duration of the exception;

[0144] 3. Normal data collection will resume after the anomaly is resolved.

[0145] In one embodiment, the preprocessing of the current boiler parameters, the first nitrogen oxide parameter, the second nitrogen oxide parameter, and the third nitrogen oxide parameter includes:

[0146] The current boiler parameters, the first nitrogen oxide parameter, the second nitrogen oxide parameter, and the third nitrogen oxide parameter are filtered using a moving average filtering algorithm to obtain their respective filtered mean values.

[0147] The filtering time window of the moving average filtering algorithm can be 10 to 300 seconds, and the specific time can be adjusted according to the operating conditions. For example, a shorter window (such as 10 seconds) can be selected in a rapidly changing scenario, while a longer window (such as 300 seconds) can be selected in a stable scenario. Then, the average value of each parameter within the filtering time window is obtained, that is, the filtered average value of the current boiler parameter, the filtered average value of the first nitrogen oxide parameter, the filtered average value of the second nitrogen oxide parameter, and the filtered average value of the third nitrogen oxide parameter within the filtering time window.

[0148] The current boiler parameters, the first nitrogen oxide parameter, the second nitrogen oxide parameter, and the third nitrogen oxide parameter are compared with their respective corresponding filtered mean values ​​to obtain the final current boiler parameters, the final first nitrogen oxide parameter, the final second nitrogen oxide parameter, and the final third nitrogen oxide parameter.

[0149] After obtaining the filtered mean of each parameter, it can be compared with the current value of each parameter, and the larger value of the two can be taken as the final value. This is to suppress noise through the filtered value and avoid excessively rapid decline. If this filtering algorithm is used, the NOx data at the denitrification outlet will decrease more gradually, avoiding the reduction of ammonia injection too quickly due to short-term fluctuations, and thus avoiding frequent adjustments to the ammonia injection volume.

[0150] Compare the filtered parameter value (e.g., the filtered value of the first nitrogen oxide parameter) with the current parameter value (e.g., the current value of the first nitrogen oxide parameter), and take the larger value as the current hysteresis decrease value, i.e., take the larger value as the output value:

[0151] Output value = MAX(current parameter value, filtered parameter value)

[0152] When using a filtering algorithm on the second nitrogen oxide parameter, if a rapid decrease in both the inlet NOx concentration and air volume is detected, the hysteresis function is canceled and the current parameter value is directly output.

[0153] Triggering conditions:

[0154] • The rate of decrease in inlet NOx concentration exceeds a set threshold (e.g., a decrease of more than 10% per minute).

[0155] • The rate of decrease in inlet air volume exceeds the set threshold (e.g., a decrease of more than 10% per minute).

[0156] ·Logical adjustment:

[0157] When the above conditions are met, the filter value and the current parameter value will no longer be increased; the current parameter value will be output directly.

[0158] • Objective: To avoid the slow decline of NOx data at the denitrification outlet due to the delayed reduction function, which would affect the timeliness of ammonia injection control, and to avoid long-term low NOx data at the denitrification outlet due to the slow reduction of ammonia injection.

[0159] Of course, to further improve the responsiveness of preprocessed data, a differential enhancement function can be introduced. By calculating the first derivative of the hysteresis descent value, the trend of data change can be captured and superimposed on the final output.

[0160] Formula definition

[0161] Let the hysteresis descent value be HysteresisValue, and its first derivative be:

[0162] The differential value of the parameter = (current hysteresis decrease value - previous hysteresis decrease value) ÷ time interval

[0163] The final output value is:

[0164] The final value of the parameter = the current hysteresis decrease value + the differential gain coefficient * the differential value of the parameter, where the parameter is the current boiler parameter, the first nitrogen oxide parameter, the second nitrogen oxide parameter and the third nitrogen oxide parameter.

[0165] Implementation steps

[0166] 1. Perform a difference operation on the hysteresis descent value to obtain the first-order differential value;

[0167] 2. Multiply the differential term by the gain coefficient and then add it to the hysteresis descent value. The differential gain coefficient is a preset value.

[0168] 3. Output the final preprocessing results.

[0169] Effect description:

[0170] During the parameter rise phase: the differential term enhances the response speed, making the parameter more sensitive; during the parameter fall phase: the hysteresis effect dominates, ensuring a smooth fall process.

[0171] In one embodiment, determining the current required ammonia amount for the denitrification system based on at least one of the preprocessed current boiler parameters, the first nitrogen oxide parameter, the second nitrogen oxide parameter, and the third nitrogen oxide parameter includes:

[0172] Based on the current boiler parameters, determine the corresponding first target ammonia quantity;

[0173] Calculate the second target ammonia quantity based on the current boiler parameters, the first nitrogen oxide parameter, and the second nitrogen oxide parameter;

[0174] Calculate the third target ammonia quantity based on the current boiler parameters and the second nitrogen oxide parameters;

[0175] Calculate the fourth target ammonia amount based on the first nitrogen oxide parameter, the second nitrogen oxide parameter, and the third nitrogen oxide parameter;

[0176] The required ammonia amount for the denitrification system is determined based on the first target ammonia amount, the second target ammonia amount, the third target ammonia amount, and the fourth target ammonia amount.

[0177] After calculating the first, second, third, and fourth target ammonia amounts, the system automatically performs a weighted sum of these amounts to obtain the total ammonia amount. This sum is then compared to a preset minimum ammonia amount. If the sum is greater than or equal to the preset minimum ammonia amount, it indicates that the sum is appropriate, and the sum is determined as the current ammonia amount required by the denitrification system. If the sum is less than the preset minimum ammonia amount, it indicates that using the sum as the current required ammonia amount is inappropriate, potentially leading to insufficient ammonia injection in the denitrification system and failure to meet environmental standards. Therefore, the preset minimum ammonia amount can be automatically determined as the current ammonia amount required by the denitrification system, ensuring that the ammonia injection amount is both sufficient and appropriate.

[0178] In one embodiment, determining the corresponding first target ammonia quantity based on the current boiler parameters includes:

[0179] Obtain historical boiler parameters;

[0180] Calculate the boiler parameter difference between the current boiler parameters and the historical boiler parameters;

[0181] The first target ammonia quantity is calculated based on the difference in the boiler parameters.

[0182] By calculating the difference between the current boiler parameters and the historical boiler parameters, the first target ammonia quantity can be automatically calculated based on this difference, thereby accurately calculating the first target ammonia quantity through the change in boiler parameters.

[0183] For example: if the coal feed rate of the coal boiler decreases by more than 9 kg compared to the previous 20 seconds, then the ammonia feed rate will increase by 20 kg within 10 seconds, and then decrease by 0.1 kg per second until it reaches 0.

[0184] formula:

[0185] If the coal feed rate decreases and is more than 9% lower than the data from 20 seconds ago...

[0186] The ammonia amount is increased by 20 kg over a 10-second delay, and then decreased by 0.1 kg per second until it reaches 0.

[0187] In one embodiment, the current boiler parameters include the current furnace air volume of the boiler; calculating the second target ammonia quantity based on the current boiler parameters, the first nitrogen oxide parameter, and the second nitrogen oxide parameter includes:

[0188] Obtain the nitrogen oxide setpoint at the total exhaust port and the nitrogen oxide setpoint at the denitrification outlet;

[0189] Obtain the actual ammonia injection rate of the denitrification system;

[0190] Determine the start and stop times of the coal mill;

[0191] The second target ammonia quantity is calculated based on the current furnace air volume, the first nitrogen oxide parameter, the second nitrogen oxide parameter, the nitrogen oxide setpoint of the total exhaust port, the nitrogen oxide setpoint of the denitrification outlet, the actual ammonia injection quantity, and the start-up and shutdown times.

[0192] By acquiring the nitrogen oxide setpoint at the total exhaust port, the nitrogen oxide setpoint at the denitrification outlet, the actual ammonia injection rate of the denitrification system, and the start-up and shutdown times of the coal mill, the second target ammonia quantity can be accurately calculated by combining these data with the current furnace air volume, the first nitrogen oxide parameter, and the second nitrogen oxide parameter, thereby improving the accuracy of the second target ammonia quantity.

[0193] In one embodiment, calculating the second target ammonia quantity based on the current furnace air volume, the first nitrogen oxide parameter, the second nitrogen oxide parameter, the nitrogen oxide setpoint of the total exhaust port, the nitrogen oxide setpoint of the denitrification outlet, the actual ammonia injection quantity, and the start-up / shutdown time includes:

[0194] Based on the first nitrogen oxide parameter, the nitrogen oxide setpoint at the denitrification outlet, and the current furnace air volume, a first preset ammonia quantity is calculated, and the curve of the first preset ammonia quantity changing over time is shown below. Figure 3A As shown;

[0195] For example: First preset ammonia quantity (mass of ammonia) = (inlet NOx concentration - outlet NOx concentration set value) * total furnace air volume * conversion factor. This conversion factor is the conversion factor between the concentration of nitrogen oxides (NOx) and the mass of ammonia, used to characterize the relationship between the concentration of nitrogen oxides and the mass of ammonia. The conversion factor = (17 / 46) / 0.283 / 1000 / 1.293.

[0196] The calculation of the first preset ammonia quantity fully considers the dynamic changes in inlet NOx concentration and air volume, and is applicable to normal operating conditions.

[0197] Based on the second nitrogen oxide parameter, the nitrogen oxide setpoint at the denitrification outlet, and the current furnace air volume, the second preset ammonia quantity is calculated, and the curve of the second preset ammonia quantity changing over time is shown below. Figure 3B As shown;

[0198] Second preset ammonia quantity = ∑(outlet NOx concentration - outlet NOx concentration setpoint) × total furnace air volume × (17 ÷ 46) ÷ 0.283 ÷ 1000 ÷ 1.293

[0199] The second preset ammonia amount is accumulated once every preset time period, that is, the second preset ammonia amount is added to the first preset ammonia amount every preset time period to fine-tune the first preset ammonia amount. This outlet is the denitrification outlet.

[0200] The second preset ammonia level is used for integration, specifically for dynamically adjusting the ammonia level, i.e., adjusting the first preset ammonia level. The implementation method is as follows:

[0201] • Dynamic adjustment is achieved through accumulators, initializers, and accumulator signals.

[0202] • The cumulative amount is calculated based on the deviation between the outlet NOx concentration and the set value of the outlet NOx concentration, as well as the air volume, and upper and lower limits are set.

[0203] Triggering conditions:

[0204] • When the NOx concentration at the outlet continues to rise and exceeds the set value, an accumulation signal is output.

[0205] • When the NOx concentration at the outlet continues to decrease and falls below the set value, an accumulation signal is output.

[0206] Features:

[0207] • By incorporating integral action into the first preset ammonia level, control accuracy is significantly improved.

[0208] In traditional PID integral algorithms, the ammonia dosage is increased if the NOx concentration deviates positively from the set value, and decreased if the deviation is negative. However, this method calculates the second preset ammonia dosage only at intervals, adjusting the ammonia dosage and fine-tuning the first preset ammonia dosage. The ammonia dosage is increased only when it is higher than the set value and continuously increases, and decreased only when it is lower than the set value and continuously decreases. Therefore, compared to traditional PID integral algorithms, the second preset ammonia dosage calculation method of this application can clearly distinguish the curve direction, improve the accuracy of ammonia dosage calculation, avoid large fluctuations in ammonia dosage, and enhance the adaptability of the algorithm.

[0209] The third preset ammonia quantity corresponding to the start and stop times is determined, and the curve of the change of the third preset ammonia quantity over time is shown in the figure. Figure 3C As shown;

[0210] When the coal mill starts, coal is added to the coal boiler, which increases the concentration of nitrogen oxides. Therefore, after the coal mill starts, the third preset ammonia amount needs to be added to the denitrification system after a 2-minute delay. When the coal mill stops, there is no coal in the coal mill and very little coal in the coal boiler, but the air volume in the coal boiler is temporarily high, causing the mixing of coal and air to become uneven. As a result, the concentration of nitrogen oxides also increases. Therefore, after the coal mill stops, the third preset ammonia amount needs to be added to the denitrification system after a 2-minute delay. In this way, the ammonia amount can be dynamically adjusted according to the start and stop time of the coal mill, avoiding control deviations caused by sudden changes in operating conditions and improving the robustness of the algorithm under special operating conditions.

[0211] Obtain historical theoretical ammonia injection volume;

[0212] The difference between the historical theoretical ammonia injection amount and the current actual ammonia injection amount is calculated and used as the fourth preset ammonia amount. In this way, a smooth transition between the theoretical ammonia amount and the actual ammonia amount can be achieved, avoiding oscillations during the switching process and improving the stability and reliability of the system.

[0213] The historical theoretical ammonia injection volume can be the theoretical ammonia injection volume during the process of manually estimating the ammonia injection volume (i.e., non-automatic calculation of the ammonia injection volume).

[0214] Using the difference between the historical theoretical ammonia injection rate and the current actual ammonia injection rate as the fourth preset ammonia rate ensures that the theoretical ammonia injection rate tracks the actual ammonia injection rate, and that the calculated theoretical ammonia injection rate can track the actual required ammonia rate in real time. In other words, it ensures that the theoretical ammonia injection rate can meet the actual ammonia requirement. The curve of this fourth preset ammonia rate changing over time is shown below. Figure 3D As shown.

[0215] The first preset ammonia amount, the second preset ammonia amount, the third preset ammonia amount, and the fourth preset ammonia amount are weighted and summed to obtain the second target ammonia amount.

[0216] By combining different parameters to calculate the first, second, third, and fourth preset ammonia amounts, the four ammonia amounts can be automatically weighted and summed to obtain the accurate second target ammonia amount.

[0217] In one embodiment, calculating the second preset ammonia quantity based on the second nitrogen oxide parameter, the nitrogen oxide setpoint at the denitrification outlet, and the current furnace air volume includes:

[0218] Every preset time interval, it is determined whether the second nitrogen oxide parameter is greater than the nitrogen oxide set value at the denitrification outlet;

[0219] If the second nitrogen oxide parameter is greater than the nitrogen oxide set value at the denitrification outlet and the second nitrogen oxide parameter continues to increase within the first preset time period, then the second preset ammonia amount is calculated based on the second nitrogen oxide parameter, the nitrogen oxide set value at the denitrification outlet, and the current furnace air volume.

[0220] If the second nitrogen oxide parameter is greater than the nitrogen oxide setting value at the denitrification outlet and continues to increase at preset time intervals, it indicates that the nitrogen oxide parameter at the denitrification outlet is too high and has not yet met the environmental protection standards, and the amount of ammonia injected is too small. Therefore, the second preset ammonia amount can be accurately calculated by combining the nitrogen oxide setting value at the denitrification outlet and the current furnace air volume, so that the nitrogen oxide parameter requirements at the denitrification outlet are fully considered when injecting ammonia.

[0221] or

[0222] In one embodiment, calculating the second preset ammonia quantity based on the second nitrogen oxide parameter, the nitrogen oxide setpoint at the denitrification outlet, and the current furnace air volume includes:

[0223] Every preset time interval, it is determined whether the second nitrogen oxide parameter is less than the nitrogen oxide set value at the denitrification outlet;

[0224] If the second nitrogen oxide parameter is less than the nitrogen oxide set value at the denitrification outlet and the second nitrogen oxide parameter continues to decrease within the second preset time period, then the second preset ammonia quantity is calculated based on the second nitrogen oxide parameter, the nitrogen oxide set value at the denitrification outlet, and the current furnace air volume.

[0225] If the second nitrogen oxide parameter is less than the nitrogen oxide setting value at the denitrification outlet and continues to decrease at preset time intervals, it indicates that the nitrogen oxide parameter at the denitrification outlet is too low and too much ammonia is being injected. Too much ammonia injection may cause blockage of the boiler air preheater. Therefore, the second preset ammonia amount can be accurately calculated by combining the second nitrogen oxide parameter, the nitrogen oxide setting value at the denitrification outlet, and the current furnace air volume, so that the nitrogen oxide parameter requirements at the denitrification outlet are fully considered when injecting ammonia.

[0226] It should be noted that, for the sake of simplicity, the foregoing method embodiments are all described as a series of actions. However, those skilled in the art should understand that this disclosure is not limited to the described order of actions, because according to this disclosure, some steps can be performed in other orders or simultaneously. Furthermore, those skilled in the art should also understand that the embodiments described in the specification are all optional embodiments, and the actions and modules involved are not necessarily essential to this disclosure.

[0227] The above is an introduction to the method embodiments. The following describes the solution described in this disclosure further through device embodiments.

[0228] Figure 4 A block diagram of an ammonia quantity control device 400 according to an embodiment of the present disclosure is shown. Figure 4 As shown, the device 400 is suitable for a denitrification system. An upstream coal-fired boiler is connected to the denitrification system. The coal-fired boiler burns pulverized coal to generate flue gas, which is then introduced into the denitrification system. The denitrification system is used to denitrify the flue gas. An upstream coal mill is connected to the coal-fired boiler. The coal mill grinds coal lumps into pulverized coal and supplies the pulverized coal to the coal-fired boiler. The device includes:

[0229] The acquisition module 410 is used to acquire the current boiler parameters of the coal-fired boiler;

[0230] The first acquisition module 420 is used to acquire the nitrogen oxide parameters at the denitrification inlet of the denitrification system as the first nitrogen oxide parameter;

[0231] The second acquisition module 430 is used to acquire the nitrogen oxide parameters at the denitrification outlet of the denitrification system as the second nitrogen oxide parameters;

[0232] The third acquisition module 440 is used to acquire the nitrogen oxide parameters of the total exhaust port of the denitrification system as the third nitrogen oxide parameter;

[0233] Preprocessing module 450 is used to preprocess the current boiler parameters, the first nitrogen oxide parameter, the second nitrogen oxide parameter and the third nitrogen oxide parameter respectively;

[0234] The determining module 460 is used to determine the current required ammonia amount of the denitrification system based on at least one of the preprocessed current boiler parameters, the first nitrogen oxide parameter, the second nitrogen oxide parameter, and the third nitrogen oxide parameter;

[0235] The ammonia injection module 470 is used to inject ammonia into the denitrification system according to the currently required ammonia amount.

[0236] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working process of the described module can be referred to the corresponding process in the foregoing method embodiments, and will not be repeated here.

[0237] According to embodiments of the present disclosure, the present disclosure also provides an electronic device and a non-transitory computer-readable storage medium storing computer instructions.

[0238] Figure 5 A schematic block diagram of an electronic device 800 that can be used to implement embodiments of the present disclosure is shown. The electronic device is intended to represent various forms of digital computers, such as laptop computers, desktop computers, workstations, personal digital assistants, servers, blade servers, mainframe computers, and other suitable computers. The electronic device may also represent various forms of mobile devices, such as personal digital processors, cellular phones, smartphones, wearable devices, and other similar computing devices. The components shown herein, their connections and relationships, and their functions are merely illustrative and are not intended to limit the implementation of the present disclosure described and / or claimed herein.

[0239] Device 800 includes a computing unit 801, which can perform various appropriate actions and processes based on a computer program stored in read-only memory (ROM) 802 or a computer program loaded from storage unit 808 into random access memory (RAM) 803. RAM 803 may also store various programs and data required for the operation of device 800. The computing unit 801, ROM 802, and RAM 803 are interconnected via bus 804. Input / output (I / O) interface 805 is also connected to bus 804.

[0240] Multiple components in device 800 are connected to I / O interface 805, including: input unit 806, such as keyboard, mouse, etc.; output unit 807, such as various types of monitors, speakers, etc.; storage unit 808, such as disk, optical disk, etc.; and communication unit 809, such as network card, modem, wireless transceiver, etc. Communication unit 809 allows device 800 to exchange information / data with other devices through computer networks such as the Internet and / or various telecommunications networks.

[0241] The computing unit 801 can be a variety of general-purpose and / or special-purpose processing components with processing and computing capabilities. Some examples of the computing unit 801 include, but are not limited to, a central processing unit (CPU), a graphics processing unit (GPU), various special-purpose artificial intelligence (AI) computing chips, various computing units running machine learning model algorithms, a digital signal processor (DSP), and any suitable processor, controller, microcontroller, etc. The computing unit 801 performs the various methods and processes described above, such as method 200. For example, in some embodiments, method 200 may be implemented as a computer software program tangibly contained in a machine-readable medium, such as storage unit 808. In some embodiments, part or all of the computer program may be loaded and / or installed on device 800 via ROM 802 and / or communication unit 809. When the computer program is loaded into RAM 803 and executed by the computing unit 801, one or more steps of method 200 described above may be performed. Alternatively, in other embodiments, the computing unit 801 may be configured to perform method 200 by any other suitable means (e.g., by means of firmware).

[0242] Various embodiments of the systems and techniques described above herein can be implemented in digital electronic circuit systems, integrated circuit systems, field-programmable gate arrays (FPGAs), application-specific integrated circuits (ASICs), application-specific standard products (ASSPs), systems-on-a-chip (SoCs), payload-programmable logic devices (CPLDs), computer hardware, firmware, software, and / or combinations thereof. These various embodiments may include implementations in one or more computer programs that can be executed and / or interpreted on a programmable system including at least one programmable processor, which may be a dedicated or general-purpose programmable processor, capable of receiving data and instructions from a storage system, at least one input device, and at least one output device, and transmitting data and instructions to the storage system, the at least one input device, and the at least one output device.

[0243] The program code used to implement the methods of this disclosure may be written in any combination of one or more programming languages. This program code may be provided to a processor or controller of a general-purpose computer, special-purpose computer, or other programmable data processing apparatus, such that when executed by the processor or controller, the program code causes the functions / operations specified in the flowcharts and / or block diagrams to be implemented. The program code may be executed entirely on a machine, partially on a machine, as a standalone software package partially on a machine and partially on a remote machine, or entirely on a remote machine or server.

[0244] In the context of this disclosure, a machine-readable medium can be a tangible medium that may contain or store a program for use by or in conjunction with an instruction execution system, apparatus, or device. A machine-readable medium can be a machine-readable signal medium or a machine-readable storage medium. A machine-readable medium can be, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, apparatus, or devices, or any suitable combination of the foregoing. More specific examples of machine-readable storage media include electrical connections based on one or more wires, portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, portable compact disk read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination of the foregoing.

[0245] To provide interaction with a user, the systems and techniques described herein can be implemented on a computer having: a display device for displaying information to the user (e.g., a CRT (cathode ray tube) or LCD (liquid crystal display) monitor); and a keyboard and pointing device (e.g., a mouse or trackball) through which the user provides input to the computer. Other types of devices can also be used to provide interaction with the user; for example, feedback provided to the user can be any form of sensory feedback (e.g., visual feedback, auditory feedback, or tactile feedback); and input from the user can be received in any form (including sound input, voice input, or tactile input).

[0246] The systems and technologies described herein can be implemented in computing systems that include backend components (e.g., as a data server), or computing systems that include middleware components (e.g., an application server), or computing systems that include frontend components (e.g., a user computer with a graphical user interface or web browser through which a user can interact with embodiments of the systems and technologies described herein), or any combination of such backend, middleware, or frontend components. The components of the system can be interconnected via digital data communication of any form or medium (e.g., a communication network). Examples of communication networks include local area networks (LANs), wide area networks (WANs), and the Internet.

[0247] Computing systems can include clients and servers. Clients and servers are generally located far apart and typically interact via communication networks. Client-server relationships are created by computer programs running on the respective computers and having a client-server relationship with each other. Servers can be cloud servers, servers in distributed systems, or servers incorporating blockchain technology.

[0248] It should be understood that the various forms of processes shown above can be used to reorder, add, or delete steps. For example, the steps described in this disclosure can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution disclosed in this disclosure can be achieved, and this is not limited herein.

[0249] The specific embodiments described above do not constitute a limitation on the scope of protection of this disclosure. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this disclosure should be included within the scope of protection of this disclosure.

Claims

1. A method for injecting ammonia based on a denitrification system, characterized in that, The method is applicable to a denitrification system, wherein a coal-fired boiler is connected upstream of the denitrification system. The coal-fired boiler is used to burn pulverized coal to generate flue gas and introduce the flue gas into the denitrification system. The denitrification system is used to denitrify the flue gas. A coal mill is connected upstream of the coal-fired boiler. The coal mill is used to grind coal lumps into pulverized coal and supply the pulverized coal to the coal-fired boiler. The method further includes: Obtain the current boiler parameters of the coal-fired boiler; The nitrogen oxide parameters at the denitrification inlet of the denitrification system are collected as the first nitrogen oxide parameter; The nitrogen oxide parameters at the denitrification outlet of the denitrification system are collected as a second nitrogen oxide parameter; The nitrogen oxide parameters of the total exhaust port of the denitrification system are collected as the third nitrogen oxide parameter; The current boiler parameters, the first nitrogen oxide parameter, the second nitrogen oxide parameter, and the third nitrogen oxide parameter are preprocessed respectively. The required ammonia amount for the denitrification system is determined based on at least one of the pre-processed current boiler parameters, the first nitrogen oxide parameter, the second nitrogen oxide parameter, and the third nitrogen oxide parameter. Ammonia is injected into the denitrification system according to the currently required ammonia amount; Determining the current required ammonia amount for the denitrification system based on at least one of the pre-processed current boiler parameters, the first nitrogen oxide parameter, the second nitrogen oxide parameter, and the third nitrogen oxide parameter includes: Based on the current boiler parameters, determine the corresponding first target ammonia quantity; Calculate the second target ammonia quantity based on the current boiler parameters, the first nitrogen oxide parameter, and the second nitrogen oxide parameter; Calculate the third target ammonia quantity based on the current boiler parameters and the second nitrogen oxide parameters; Calculate the fourth target ammonia amount based on the first nitrogen oxide parameter, the second nitrogen oxide parameter, and the third nitrogen oxide parameter; The required ammonia amount for the denitrification system is determined based on the first target ammonia amount, the second target ammonia amount, the third target ammonia amount, and the fourth target ammonia amount.

2. The method as described in claim 1, characterized in that, The preprocessing of the current boiler parameters, the first nitrogen oxide parameter, the second nitrogen oxide parameter, and the third nitrogen oxide parameter includes: Based on the current temperature and pressure at each measurement point of the current boiler parameters, the first nitrogen oxide parameter, the second nitrogen oxide parameter, and the third nitrogen oxide parameter, the concentration units of the current boiler parameters, the first nitrogen oxide parameter, the second nitrogen oxide parameter, and the third nitrogen oxide parameter are uniformly converted. The denitrification inlet, the denitrification outlet, and the main exhaust port are purged. Anomaly tracking is performed on the parameters of the denitrification inlet and the denitrification outlet.

3. The method as described in claim 2, characterized in that, The parameter anomaly tracking for the denitrification inlet and the denitrification outlet includes: When there are multiple denitrification inlets, if all of the denitrification inlets are in normal working condition, the first nitrogen oxide parameter collected at each of the denitrification inlets is retained; otherwise, if any of the denitrification inlets is in abnormal working condition, the value of the first nitrogen oxide parameter of any of the denitrification inlets is taken from the value of the first nitrogen oxide parameter of the other denitrification inlets. When there are multiple denitrification outlets, if all of the denitrification outlets are in normal working condition, the second nitrogen oxide parameter collected from each of the denitrification outlets is retained; otherwise, if any of the denitrification outlets is in abnormal working condition, the value of the second nitrogen oxide parameter of any denitrification outlet is taken from the value of the second nitrogen oxide parameter of the other denitrification outlets.

4. The method as described in claim 2, characterized in that, The parameter anomaly tracking for the denitrification inlet and the denitrification outlet includes: When there is only one denitrification inlet, if the denitrification inlet is in normal working condition, the first nitrogen oxide parameter collected by the denitrification inlet is retained; otherwise, if the denitrification inlet is in abnormal working condition, the value of the first nitrogen oxide parameter of the denitrification inlet is taken from the historical value of the first nitrogen oxide parameter of the denitrification inlet. When there is only one denitrification outlet, if the denitrification outlet is in normal working condition, the second nitrogen oxide parameter collected at the denitrification outlet is retained; otherwise, if the denitrification outlet is in abnormal working condition, the value of the second nitrogen oxide parameter at the denitrification outlet is taken from the historical value of the second nitrogen oxide parameter at the denitrification outlet.

5. The method as described in claim 1, characterized in that, The preprocessing of the current boiler parameters, the first nitrogen oxide parameter, the second nitrogen oxide parameter, and the third nitrogen oxide parameter includes: The current boiler parameters, the first nitrogen oxide parameter, the second nitrogen oxide parameter, and the third nitrogen oxide parameter are filtered using a moving average filtering algorithm to obtain their respective filtered mean values. The current boiler parameters, the first nitrogen oxide parameter, the second nitrogen oxide parameter, and the third nitrogen oxide parameter are compared with their respective corresponding filtered mean values ​​to obtain the final current boiler parameters, the final first nitrogen oxide parameter, the final second nitrogen oxide parameter, and the final third nitrogen oxide parameter.

6. The method as described in claim 1, characterized in that, The step of determining the corresponding first target ammonia quantity based on the current boiler parameters includes: Obtain historical boiler parameters; Calculate the boiler parameter difference between the current boiler parameters and the historical boiler parameters; Calculate the first target ammonia quantity based on the boiler parameter differences; The current boiler parameters include the current furnace air volume of the boiler; the calculation of the second target ammonia quantity based on the current boiler parameters, the first nitrogen oxide parameter, and the second nitrogen oxide parameter includes: Obtain the nitrogen oxide setpoint at the total exhaust port and the nitrogen oxide setpoint at the denitrification outlet; Obtain the actual ammonia injection rate of the denitrification system; Determine the start and stop times of the coal mill; The second target ammonia quantity is calculated based on the current furnace air volume, the first nitrogen oxide parameter, the second nitrogen oxide parameter, the nitrogen oxide setpoint of the total exhaust port, the nitrogen oxide setpoint of the denitrification outlet, the actual ammonia injection quantity, and the start-up and shutdown times.

7. The method as described in claim 6, characterized in that, The calculation of the second target ammonia quantity based on the current furnace air volume, the first nitrogen oxide parameter, the second nitrogen oxide parameter, the nitrogen oxide setpoint of the total exhaust port, the nitrogen oxide setpoint of the denitrification outlet, the actual ammonia injection quantity, and the start-up and shutdown times includes: Calculate the first preset ammonia amount based on the first nitrogen oxide parameter, the nitrogen oxide set value at the denitrification outlet, and the current furnace air volume; The second preset ammonia quantity is calculated based on the second nitrogen oxide parameter, the nitrogen oxide set value at the denitrification outlet, and the current furnace air volume; Determine the third preset ammonia quantity corresponding to the start / stop time; Obtain historical theoretical ammonia injection volume; The difference between the historical theoretical ammonia injection amount and the current actual ammonia injection amount is calculated and used as the fourth preset ammonia amount; The first preset ammonia amount, the second preset ammonia amount, the third preset ammonia amount, and the fourth preset ammonia amount are weighted and summed to obtain the second target ammonia amount.

8. The method as described in claim 7, characterized in that, The step of calculating the second preset ammonia quantity based on the second nitrogen oxide parameter, the nitrogen oxide setpoint at the denitrification outlet, and the current furnace air volume includes: Every preset time interval, it is determined whether the second nitrogen oxide parameter is greater than the nitrogen oxide set value at the denitrification outlet; If the second nitrogen oxide parameter is greater than the nitrogen oxide set value at the denitrification outlet and the second nitrogen oxide parameter continues to increase within the first preset time period, then the second preset ammonia amount is calculated based on the second nitrogen oxide parameter, the nitrogen oxide set value at the denitrification outlet, and the current furnace air volume. or Every preset time interval, it is determined whether the second nitrogen oxide parameter is less than the nitrogen oxide set value at the denitrification outlet; If the second nitrogen oxide parameter is less than the nitrogen oxide set value at the denitrification outlet and the second nitrogen oxide parameter continues to decrease within the second preset time period, then the second preset ammonia quantity is calculated based on the second nitrogen oxide parameter, the nitrogen oxide set value at the denitrification outlet, and the current furnace air volume.

9. An ammonia injection device based on a denitrification system, characterized in that, The device is suitable for a denitrification system, wherein a coal-fired boiler is connected upstream of the denitrification system. The coal-fired boiler is used to burn pulverized coal to generate flue gas and introduce the flue gas into the denitrification system. The denitrification system is used to denitrify the flue gas. A coal mill is connected upstream of the coal-fired boiler. The coal mill is used to grind coal lumps into pulverized coal and supply the pulverized coal to the coal-fired boiler. The device includes: The acquisition module is used to acquire the current boiler parameters of the coal-fired boiler; The first acquisition module is used to acquire the nitrogen oxide parameters at the denitrification inlet of the denitrification system as the first nitrogen oxide parameter; The second acquisition module is used to acquire the nitrogen oxide parameters at the denitrification outlet of the denitrification system as the second nitrogen oxide parameters; The third acquisition module is used to acquire the nitrogen oxide parameters of the total exhaust port of the denitrification system as the third nitrogen oxide parameter; The preprocessing module is used to preprocess the current boiler parameters, the first nitrogen oxide parameter, the second nitrogen oxide parameter, and the third nitrogen oxide parameter respectively. The determination module is used to determine the current ammonia amount required by the denitrification system based on at least one of the preprocessed current boiler parameters, the first nitrogen oxide parameter, the second nitrogen oxide parameter, and the third nitrogen oxide parameter; The ammonia injection module is used to inject ammonia into the denitrification system according to the currently required ammonia amount; The determining module is specifically used for: Based on the current boiler parameters, determine the corresponding first target ammonia quantity; Calculate the second target ammonia quantity based on the current boiler parameters, the first nitrogen oxide parameter, and the second nitrogen oxide parameter; Calculate the third target ammonia quantity based on the current boiler parameters and the second nitrogen oxide parameters; Calculate the fourth target ammonia amount based on the first nitrogen oxide parameter, the second nitrogen oxide parameter, and the third nitrogen oxide parameter; determine the current ammonia amount required by the denitrification system based on the first target ammonia amount, the second target ammonia amount, the third target ammonia amount, and the fourth target ammonia amount.

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